// SPDX-License-Identifier: GPL-2.0-or-later
/******************************************************************************
**  Device driver for the PCI-SCSI NCR538XX controller family.
**
**  Copyright (C) 1994  Wolfgang Stanglmeier
**
**
**-----------------------------------------------------------------------------
**
**  This driver has been ported to Linux from the FreeBSD NCR53C8XX driver
**  and is currently maintained by
**
**          Gerard Roudier              <groudier@free.fr>
**
**  Being given that this driver originates from the FreeBSD version, and
**  in order to keep synergy on both, any suggested enhancements and corrections
**  received on Linux are automatically a potential candidate for the FreeBSD 
**  version.
**
**  The original driver has been written for 386bsd and FreeBSD by
**          Wolfgang Stanglmeier        <wolf@cologne.de>
**          Stefan Esser                <se@mi.Uni-Koeln.de>
**
**  And has been ported to NetBSD by
**          Charles M. Hannum           <mycroft@gnu.ai.mit.edu>
**
**-----------------------------------------------------------------------------
**
**                     Brief history
**
**  December 10 1995 by Gerard Roudier:
**     Initial port to Linux.
**
**  June 23 1996 by Gerard Roudier:
**     Support for 64 bits architectures (Alpha).
**
**  November 30 1996 by Gerard Roudier:
**     Support for Fast-20 scsi.
**     Support for large DMA fifo and 128 dwords bursting.
**
**  February 27 1997 by Gerard Roudier:
**     Support for Fast-40 scsi.
**     Support for on-Board RAM.
**
**  May 3 1997 by Gerard Roudier:
**     Full support for scsi scripts instructions pre-fetching.
**
**  May 19 1997 by Richard Waltham <dormouse@farsrobt.demon.co.uk>:
**     Support for NvRAM detection and reading.
**
**  August 18 1997 by Cort <cort@cs.nmt.edu>:
**     Support for Power/PC (Big Endian).
**
**  June 20 1998 by Gerard Roudier
**     Support for up to 64 tags per lun.
**     O(1) everywhere (C and SCRIPTS) for normal cases.
**     Low PCI traffic for command handling when on-chip RAM is present.
**     Aggressive SCSI SCRIPTS optimizations.
**
**  2005 by Matthew Wilcox and James Bottomley
**     PCI-ectomy.  This driver now supports only the 720 chip (see the
**     NCR_Q720 and zalon drivers for the bus probe logic).
**
*******************************************************************************
*/

/*
**      Supported SCSI-II features:
**          Synchronous negotiation
**          Wide negotiation        (depends on the NCR Chip)
**          Enable disconnection
**          Tagged command queuing
**          Parity checking
**          Etc...
**
**      Supported NCR/SYMBIOS chips:
**              53C720          (Wide,   Fast SCSI-2, intfly problems)
*/

/* Name and version of the driver */
#define SCSI_NCR_DRIVER_NAME    "ncr53c8xx-3.4.3g"

#define SCSI_NCR_DEBUG_FLAGS    (0)

#include <linux/blkdev.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/errno.h>
#include <linux/gfp.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/signal.h>
#include <linux/spinlock.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/time.h>
#include <linux/timer.h>
#include <linux/types.h>

#include <asm/dma.h>
#include <asm/io.h>

#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_tcq.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_spi.h>

#include "ncr53c8xx.h"

#define NAME53C8XX              "ncr53c8xx"

/*==========================================================
**
**      Debugging tags
**
**==========================================================
*/

#define DEBUG_ALLOC    (0x0001)
#define DEBUG_PHASE    (0x0002)
#define DEBUG_QUEUE    (0x0008)
#define DEBUG_RESULT   (0x0010)
#define DEBUG_POINTER  (0x0020)
#define DEBUG_SCRIPT   (0x0040)
#define DEBUG_TINY     (0x0080)
#define DEBUG_TIMING   (0x0100)
#define DEBUG_NEGO     (0x0200)
#define DEBUG_TAGS     (0x0400)
#define DEBUG_SCATTER  (0x0800)
#define DEBUG_IC        (0x1000)

/*
**    Enable/Disable debug messages.
**    Can be changed at runtime too.
*/

#ifdef SCSI_NCR_DEBUG_INFO_SUPPORT
static int ncr_debug = SCSI_NCR_DEBUG_FLAGS;
        #define DEBUG_FLAGS ncr_debug
#else
        #define DEBUG_FLAGS     SCSI_NCR_DEBUG_FLAGS
#endif

/*
 * Locally used status flag
 */
#define SAM_STAT_ILLEGAL        0xff

static inline struct list_head *ncr_list_pop(struct list_head *head)
{
        if (!list_empty(head)) {
                struct list_head *elem = head->next;

                list_del(elem);
                return elem;
        }

        return NULL;
}

/*==========================================================
**
**      Simple power of two buddy-like allocator.
**
**      This simple code is not intended to be fast, but to 
**      provide power of 2 aligned memory allocations.
**      Since the SCRIPTS processor only supplies 8 bit 
**      arithmetic, this allocator allows simple and fast 
**      address calculations  from the SCRIPTS code.
**      In addition, cache line alignment is guaranteed for 
**      power of 2 cache line size.
**      Enhanced in linux-2.3.44 to provide a memory pool 
**      per pcidev to support dynamic dma mapping. (I would 
**      have preferred a real bus abstraction, btw).
**
**==========================================================
*/

#define MEMO_SHIFT      4       /* 16 bytes minimum memory chunk */
#if PAGE_SIZE >= 8192
#define MEMO_PAGE_ORDER 0       /* 1 PAGE  maximum */
#else
#define MEMO_PAGE_ORDER 1       /* 2 PAGES maximum */
#endif
#define MEMO_FREE_UNUSED        /* Free unused pages immediately */
#define MEMO_WARN       1
#define MEMO_GFP_FLAGS  GFP_ATOMIC
#define MEMO_CLUSTER_SHIFT      (PAGE_SHIFT+MEMO_PAGE_ORDER)
#define MEMO_CLUSTER_SIZE       (1UL << MEMO_CLUSTER_SHIFT)
#define MEMO_CLUSTER_MASK       (MEMO_CLUSTER_SIZE-1)

typedef u_long m_addr_t;        /* Enough bits to bit-hack addresses */
typedef struct device *m_bush_t;        /* Something that addresses DMAable */

typedef struct m_link {         /* Link between free memory chunks */
        struct m_link *next;
} m_link_s;

typedef struct m_vtob {         /* Virtual to Bus address translation */
        struct m_vtob *next;
        m_addr_t vaddr;
        m_addr_t baddr;
} m_vtob_s;
#define VTOB_HASH_SHIFT         5
#define VTOB_HASH_SIZE          (1UL << VTOB_HASH_SHIFT)
#define VTOB_HASH_MASK          (VTOB_HASH_SIZE-1)
#define VTOB_HASH_CODE(m)       \
        ((((m_addr_t) (m)) >> MEMO_CLUSTER_SHIFT) & VTOB_HASH_MASK)

typedef struct m_pool {         /* Memory pool of a given kind */
        m_bush_t bush;
        m_addr_t (*getp)(struct m_pool *);
        void (*freep)(struct m_pool *, m_addr_t);
        int nump;
        m_vtob_s *(vtob[VTOB_HASH_SIZE]);
        struct m_pool *next;
        struct m_link h[PAGE_SHIFT-MEMO_SHIFT+MEMO_PAGE_ORDER+1];
} m_pool_s;

static void *___m_alloc(m_pool_s *mp, int size)
{
        int i = 0;
        int s = (1 << MEMO_SHIFT);
        int j;
        m_addr_t a;
        m_link_s *h = mp->h;

        if (size > (PAGE_SIZE << MEMO_PAGE_ORDER))
                return NULL;

        while (size > s) {
                s <<= 1;
                ++i;
        }

        j = i;
        while (!h[j].next) {
                if (s == (PAGE_SIZE << MEMO_PAGE_ORDER)) {
                        h[j].next = (m_link_s *)mp->getp(mp);
                        if (h[j].next)
                                h[j].next->next = NULL;
                        break;
                }
                ++j;
                s <<= 1;
        }
        a = (m_addr_t) h[j].next;
        if (a) {
                h[j].next = h[j].next->next;
                while (j > i) {
                        j -= 1;
                        s >>= 1;
                        h[j].next = (m_link_s *) (a+s);
                        h[j].next->next = NULL;
                }
        }
#ifdef DEBUG
        printk("___m_alloc(%d) = %p\n", size, (void *) a);
#endif
        return (void *) a;
}

static void ___m_free(m_pool_s *mp, void *ptr, int size)
{
        int i = 0;
        int s = (1 << MEMO_SHIFT);
        m_link_s *q;
        m_addr_t a, b;
        m_link_s *h = mp->h;

#ifdef DEBUG
        printk("___m_free(%p, %d)\n", ptr, size);
#endif

        if (size > (PAGE_SIZE << MEMO_PAGE_ORDER))
                return;

        while (size > s) {
                s <<= 1;
                ++i;
        }

        a = (m_addr_t) ptr;

        while (1) {
#ifdef MEMO_FREE_UNUSED
                if (s == (PAGE_SIZE << MEMO_PAGE_ORDER)) {
                        mp->freep(mp, a);
                        break;
                }
#endif
                b = a ^ s;
                q = &h[i];
                while (q->next && q->next != (m_link_s *) b) {
                        q = q->next;
                }
                if (!q->next) {
                        ((m_link_s *) a)->next = h[i].next;
                        h[i].next = (m_link_s *) a;
                        break;
                }
                q->next = q->next->next;
                a = a & b;
                s <<= 1;
                ++i;
        }
}

static DEFINE_SPINLOCK(ncr53c8xx_lock);

static void *__m_calloc2(m_pool_s *mp, int size, char *name, int uflags)
{
        void *p;

        p = ___m_alloc(mp, size);

        if (DEBUG_FLAGS & DEBUG_ALLOC)
                printk ("new %-10s[%4d] @%p.\n", name, size, p);

        if (p)
                memset(p, 0, size);
        else if (uflags & MEMO_WARN)
                printk (NAME53C8XX ": failed to allocate %s[%d]\n", name, size);

        return p;
}

#define __m_calloc(mp, s, n)    __m_calloc2(mp, s, n, MEMO_WARN)

static void __m_free(m_pool_s *mp, void *ptr, int size, char *name)
{
        if (DEBUG_FLAGS & DEBUG_ALLOC)
                printk ("freeing %-10s[%4d] @%p.\n", name, size, ptr);

        ___m_free(mp, ptr, size);

}

/*
 * With pci bus iommu support, we use a default pool of unmapped memory 
 * for memory we donnot need to DMA from/to and one pool per pcidev for 
 * memory accessed by the PCI chip. `mp0' is the default not DMAable pool.
 */

static m_addr_t ___mp0_getp(m_pool_s *mp)
{
        m_addr_t m = __get_free_pages(MEMO_GFP_FLAGS, MEMO_PAGE_ORDER);
        if (m)
                ++mp->nump;
        return m;
}

static void ___mp0_freep(m_pool_s *mp, m_addr_t m)
{
        free_pages(m, MEMO_PAGE_ORDER);
        --mp->nump;
}

static m_pool_s mp0 = {NULL, ___mp0_getp, ___mp0_freep};

/*
 * DMAable pools.
 */

/*
 * With pci bus iommu support, we maintain one pool per pcidev and a 
 * hashed reverse table for virtual to bus physical address translations.
 */
static m_addr_t ___dma_getp(m_pool_s *mp)
{
        m_addr_t vp;
        m_vtob_s *vbp;

        vbp = __m_calloc(&mp0, sizeof(*vbp), "VTOB");
        if (vbp) {
                dma_addr_t daddr;
                vp = (m_addr_t) dma_alloc_coherent(mp->bush,
                                                PAGE_SIZE<<MEMO_PAGE_ORDER,
                                                &daddr, GFP_ATOMIC);
                if (vp) {
                        int hc = VTOB_HASH_CODE(vp);
                        vbp->vaddr = vp;
                        vbp->baddr = daddr;
                        vbp->next = mp->vtob[hc];
                        mp->vtob[hc] = vbp;
                        ++mp->nump;
                        return vp;
                }
        }
        if (vbp)
                __m_free(&mp0, vbp, sizeof(*vbp), "VTOB");
        return 0;
}

static void ___dma_freep(m_pool_s *mp, m_addr_t m)
{
        m_vtob_s **vbpp, *vbp;
        int hc = VTOB_HASH_CODE(m);

        vbpp = &mp->vtob[hc];
        while (*vbpp && (*vbpp)->vaddr != m)
                vbpp = &(*vbpp)->next;
        if (*vbpp) {
                vbp = *vbpp;
                *vbpp = (*vbpp)->next;
                dma_free_coherent(mp->bush, PAGE_SIZE<<MEMO_PAGE_ORDER,
                                  (void *)vbp->vaddr, (dma_addr_t)vbp->baddr);
                __m_free(&mp0, vbp, sizeof(*vbp), "VTOB");
                --mp->nump;
        }
}

static inline m_pool_s *___get_dma_pool(m_bush_t bush)
{
        m_pool_s *mp;
        for (mp = mp0.next; mp && mp->bush != bush; mp = mp->next);
        return mp;
}

static m_pool_s *___cre_dma_pool(m_bush_t bush)
{
        m_pool_s *mp;
        mp = __m_calloc(&mp0, sizeof(*mp), "MPOOL");
        if (mp) {
                memset(mp, 0, sizeof(*mp));
                mp->bush = bush;
                mp->getp = ___dma_getp;
                mp->freep = ___dma_freep;
                mp->next = mp0.next;
                mp0.next = mp;
        }
        return mp;
}

static void ___del_dma_pool(m_pool_s *p)
{
        struct m_pool **pp = &mp0.next;

        while (*pp && *pp != p)
                pp = &(*pp)->next;
        if (*pp) {
                *pp = (*pp)->next;
                __m_free(&mp0, p, sizeof(*p), "MPOOL");
        }
}

static void *__m_calloc_dma(m_bush_t bush, int size, char *name)
{
        u_long flags;
        struct m_pool *mp;
        void *m = NULL;

        spin_lock_irqsave(&ncr53c8xx_lock, flags);
        mp = ___get_dma_pool(bush);
        if (!mp)
                mp = ___cre_dma_pool(bush);
        if (mp)
                m = __m_calloc(mp, size, name);
        if (mp && !mp->nump)
                ___del_dma_pool(mp);
        spin_unlock_irqrestore(&ncr53c8xx_lock, flags);

        return m;
}

static void __m_free_dma(m_bush_t bush, void *m, int size, char *name)
{
        u_long flags;
        struct m_pool *mp;

        spin_lock_irqsave(&ncr53c8xx_lock, flags);
        mp = ___get_dma_pool(bush);
        if (mp)
                __m_free(mp, m, size, name);
        if (mp && !mp->nump)
                ___del_dma_pool(mp);
        spin_unlock_irqrestore(&ncr53c8xx_lock, flags);
}

static m_addr_t __vtobus(m_bush_t bush, void *m)
{
        u_long flags;
        m_pool_s *mp;
        int hc = VTOB_HASH_CODE(m);
        m_vtob_s *vp = NULL;
        m_addr_t a = ((m_addr_t) m) & ~MEMO_CLUSTER_MASK;

        spin_lock_irqsave(&ncr53c8xx_lock, flags);
        mp = ___get_dma_pool(bush);
        if (mp) {
                vp = mp->vtob[hc];
                while (vp && (m_addr_t) vp->vaddr != a)
                        vp = vp->next;
        }
        spin_unlock_irqrestore(&ncr53c8xx_lock, flags);
        return vp ? vp->baddr + (((m_addr_t) m) - a) : 0;
}

#define _m_calloc_dma(np, s, n)         __m_calloc_dma(np->dev, s, n)
#define _m_free_dma(np, p, s, n)        __m_free_dma(np->dev, p, s, n)
#define m_calloc_dma(s, n)              _m_calloc_dma(np, s, n)
#define m_free_dma(p, s, n)             _m_free_dma(np, p, s, n)
#define _vtobus(np, p)                  __vtobus(np->dev, p)
#define vtobus(p)                       _vtobus(np, p)

/*
 *  Deal with DMA mapping/unmapping.
 */

static void __unmap_scsi_data(struct device *dev, struct scsi_cmnd *cmd)
{
        struct ncr_cmd_priv *cmd_priv = scsi_cmd_priv(cmd);

        switch(cmd_priv->data_mapped) {
        case 2:
                scsi_dma_unmap(cmd);
                break;
        }
        cmd_priv->data_mapped = 0;
}

static int __map_scsi_sg_data(struct device *dev, struct scsi_cmnd *cmd)
{
        struct ncr_cmd_priv *cmd_priv = scsi_cmd_priv(cmd);
        int use_sg;

        use_sg = scsi_dma_map(cmd);
        if (!use_sg)
                return 0;

        cmd_priv->data_mapped = 2;
        cmd_priv->data_mapping = use_sg;

        return use_sg;
}

#define unmap_scsi_data(np, cmd)        __unmap_scsi_data(np->dev, cmd)
#define map_scsi_sg_data(np, cmd)       __map_scsi_sg_data(np->dev, cmd)

/*==========================================================
**
**      Driver setup.
**
**      This structure is initialized from linux config 
**      options. It can be overridden at boot-up by the boot 
**      command line.
**
**==========================================================
*/
static struct ncr_driver_setup
        driver_setup                    = SCSI_NCR_DRIVER_SETUP;

#ifndef MODULE
#ifdef  SCSI_NCR_BOOT_COMMAND_LINE_SUPPORT
static struct ncr_driver_setup
        driver_safe_setup __initdata    = SCSI_NCR_DRIVER_SAFE_SETUP;
#endif
#endif /* !MODULE */

#define initverbose (driver_setup.verbose)
#define bootverbose (np->verbose)


/*===================================================================
**
**      Driver setup from the boot command line
**
**===================================================================
*/

#ifdef MODULE
#define ARG_SEP ' '
#else
#define ARG_SEP ','
#endif

#define OPT_TAGS                1
#define OPT_MASTER_PARITY       2
#define OPT_SCSI_PARITY         3
#define OPT_DISCONNECTION       4
#define OPT_SPECIAL_FEATURES    5
#define OPT_UNUSED_1            6
#define OPT_FORCE_SYNC_NEGO     7
#define OPT_REVERSE_PROBE       8
#define OPT_DEFAULT_SYNC        9
#define OPT_VERBOSE             10
#define OPT_DEBUG               11
#define OPT_BURST_MAX           12
#define OPT_LED_PIN             13
#define OPT_MAX_WIDE            14
#define OPT_SETTLE_DELAY        15
#define OPT_DIFF_SUPPORT        16
#define OPT_IRQM                17
#define OPT_PCI_FIX_UP          18
#define OPT_BUS_CHECK           19
#define OPT_OPTIMIZE            20
#define OPT_RECOVERY            21
#define OPT_SAFE_SETUP          22
#define OPT_USE_NVRAM           23
#define OPT_EXCLUDE             24
#define OPT_HOST_ID             25

#ifdef SCSI_NCR_IARB_SUPPORT
#define OPT_IARB                26
#endif

#ifdef MODULE
#define ARG_SEP ' '
#else
#define ARG_SEP ','
#endif

#ifndef MODULE
static char setup_token[] __initdata = 
        "tags:"   "mpar:"
        "spar:"   "disc:"
        "specf:"  "ultra:"
        "fsn:"    "revprob:"
        "sync:"   "verb:"
        "debug:"  "burst:"
        "led:"    "wide:"
        "settle:" "diff:"
        "irqm:"   "pcifix:"
        "buschk:" "optim:"
        "recovery:"
        "safe:"   "nvram:"
        "excl:"   "hostid:"
#ifdef SCSI_NCR_IARB_SUPPORT
        "iarb:"
#endif
        ;       /* DONNOT REMOVE THIS ';' */

static int __init get_setup_token(char *p)
{
        char *cur = setup_token;
        char *pc;
        int i = 0;

        while (cur != NULL && (pc = strchr(cur, ':')) != NULL) {
                ++pc;
                ++i;
                if (!strncmp(p, cur, pc - cur))
                        return i;
                cur = pc;
        }
        return 0;
}

static int __init sym53c8xx__setup(char *str)
{
#ifdef SCSI_NCR_BOOT_COMMAND_LINE_SUPPORT
        char *cur = str;
        char *pc, *pv;
        int i, val, c;
        int xi = 0;

        while (cur != NULL && (pc = strchr(cur, ':')) != NULL) {
                char *pe;

                val = 0;
                pv = pc;
                c = *++pv;

                if      (c == 'n')
                        val = 0;
                else if (c == 'y')
                        val = 1;
                else
                        val = (int) simple_strtoul(pv, &pe, 0);

                switch (get_setup_token(cur)) {
                case OPT_TAGS:
                        driver_setup.default_tags = val;
                        if (pe && *pe == '/') {
                                i = 0;
                                while (*pe && *pe != ARG_SEP && 
                                        i < sizeof(driver_setup.tag_ctrl)-1) {
                                        driver_setup.tag_ctrl[i++] = *pe++;
                                }
                                driver_setup.tag_ctrl[i] = '\0';
                        }
                        break;
                case OPT_MASTER_PARITY:
                        driver_setup.master_parity = val;
                        break;
                case OPT_SCSI_PARITY:
                        driver_setup.scsi_parity = val;
                        break;
                case OPT_DISCONNECTION:
                        driver_setup.disconnection = val;
                        break;
                case OPT_SPECIAL_FEATURES:
                        driver_setup.special_features = val;
                        break;
                case OPT_FORCE_SYNC_NEGO:
                        driver_setup.force_sync_nego = val;
                        break;
                case OPT_REVERSE_PROBE:
                        driver_setup.reverse_probe = val;
                        break;
                case OPT_DEFAULT_SYNC:
                        driver_setup.default_sync = val;
                        break;
                case OPT_VERBOSE:
                        driver_setup.verbose = val;
                        break;
                case OPT_DEBUG:
                        driver_setup.debug = val;
                        break;
                case OPT_BURST_MAX:
                        driver_setup.burst_max = val;
                        break;
                case OPT_LED_PIN:
                        driver_setup.led_pin = val;
                        break;
                case OPT_MAX_WIDE:
                        driver_setup.max_wide = val? 1:0;
                        break;
                case OPT_SETTLE_DELAY:
                        driver_setup.settle_delay = val;
                        break;
                case OPT_DIFF_SUPPORT:
                        driver_setup.diff_support = val;
                        break;
                case OPT_IRQM:
                        driver_setup.irqm = val;
                        break;
                case OPT_PCI_FIX_UP:
                        driver_setup.pci_fix_up = val;
                        break;
                case OPT_BUS_CHECK:
                        driver_setup.bus_check = val;
                        break;
                case OPT_OPTIMIZE:
                        driver_setup.optimize = val;
                        break;
                case OPT_RECOVERY:
                        driver_setup.recovery = val;
                        break;
                case OPT_USE_NVRAM:
                        driver_setup.use_nvram = val;
                        break;
                case OPT_SAFE_SETUP:
                        memcpy(&driver_setup, &driver_safe_setup,
                                sizeof(driver_setup));
                        break;
                case OPT_EXCLUDE:
                        if (xi < SCSI_NCR_MAX_EXCLUDES)
                                driver_setup.excludes[xi++] = val;
                        break;
                case OPT_HOST_ID:
                        driver_setup.host_id = val;
                        break;
#ifdef SCSI_NCR_IARB_SUPPORT
                case OPT_IARB:
                        driver_setup.iarb = val;
                        break;
#endif
                default:
                        printk("sym53c8xx_setup: unexpected boot option '%.*s' ignored\n", (int)(pc-cur+1), cur);
                        break;
                }

                if ((cur = strchr(cur, ARG_SEP)) != NULL)
                        ++cur;
        }
#endif /* SCSI_NCR_BOOT_COMMAND_LINE_SUPPORT */
        return 1;
}
#endif /* !MODULE */

/*===================================================================
**
**      Get device queue depth from boot command line.
**
**===================================================================
*/
#define DEF_DEPTH       (driver_setup.default_tags)
#define ALL_TARGETS     -2
#define NO_TARGET       -1
#define ALL_LUNS        -2
#define NO_LUN          -1

static int device_queue_depth(int unit, int target, int lun)
{
        int c, h, t, u, v;
        char *p = driver_setup.tag_ctrl;
        char *ep;

        h = -1;
        t = NO_TARGET;
        u = NO_LUN;
        while ((c = *p++) != 0) {
                v = simple_strtoul(p, &ep, 0);
                switch(c) {
                case '/':
                        ++h;
                        t = ALL_TARGETS;
                        u = ALL_LUNS;
                        break;
                case 't':
                        if (t != target)
                                t = (target == v) ? v : NO_TARGET;
                        u = ALL_LUNS;
                        break;
                case 'u':
                        if (u != lun)
                                u = (lun == v) ? v : NO_LUN;
                        break;
                case 'q':
                        if (h == unit &&
                                (t == ALL_TARGETS || t == target) &&
                                (u == ALL_LUNS    || u == lun))
                                return v;
                        break;
                case '-':
                        t = ALL_TARGETS;
                        u = ALL_LUNS;
                        break;
                default:
                        break;
                }
                p = ep;
        }
        return DEF_DEPTH;
}


/*==========================================================
**
**      The CCB done queue uses an array of CCB virtual 
**      addresses. Empty entries are flagged using the bogus 
**      virtual address 0xffffffff.
**
**      Since PCI ensures that only aligned DWORDs are accessed 
**      atomically, 64 bit little-endian architecture requires 
**      to test the high order DWORD of the entry to determine 
**      if it is empty or valid.
**
**      BTW, I will make things differently as soon as I will 
**      have a better idea, but this is simple and should work.
**
**==========================================================
*/
 
#define SCSI_NCR_CCB_DONE_SUPPORT
#ifdef  SCSI_NCR_CCB_DONE_SUPPORT

#define MAX_DONE 24
#define CCB_DONE_EMPTY 0xffffffffUL

/* All 32 bit architectures */
#if BITS_PER_LONG == 32
#define CCB_DONE_VALID(cp)  (((u_long) cp) != CCB_DONE_EMPTY)

/* All > 32 bit (64 bit) architectures regardless endian-ness */
#else
#define CCB_DONE_VALID(cp)  \
        ((((u_long) cp) & 0xffffffff00000000ul) &&      \
         (((u_long) cp) & 0xfffffffful) != CCB_DONE_EMPTY)
#endif

#endif /* SCSI_NCR_CCB_DONE_SUPPORT */

/*==========================================================
**
**      Configuration and Debugging
**
**==========================================================
*/

/*
**    SCSI address of this device.
**    The boot routines should have set it.
**    If not, use this.
*/

#ifndef SCSI_NCR_MYADDR
#define SCSI_NCR_MYADDR      (7)
#endif

/*
**    The maximum number of tags per logic unit.
**    Used only for disk devices that support tags.
*/

#ifndef SCSI_NCR_MAX_TAGS
#define SCSI_NCR_MAX_TAGS    (8)
#endif

/*
**    TAGS are actually limited to 64 tags/lun.
**    We need to deal with power of 2, for alignment constraints.
*/
#if     SCSI_NCR_MAX_TAGS > 64
#define MAX_TAGS (64)
#else
#define MAX_TAGS SCSI_NCR_MAX_TAGS
#endif

#define NO_TAG  (255)

/*
**      Choose appropriate type for tag bitmap.
*/
#if     MAX_TAGS > 32
typedef u64 tagmap_t;
#else
typedef u32 tagmap_t;
#endif

/*
**    Number of targets supported by the driver.
**    n permits target numbers 0..n-1.
**    Default is 16, meaning targets #0..#15.
**    #7 .. is myself.
*/

#ifdef SCSI_NCR_MAX_TARGET
#define MAX_TARGET  (SCSI_NCR_MAX_TARGET)
#else
#define MAX_TARGET  (16)
#endif

/*
**    Number of logic units supported by the driver.
**    n enables logic unit numbers 0..n-1.
**    The common SCSI devices require only
**    one lun, so take 1 as the default.
*/

#ifdef SCSI_NCR_MAX_LUN
#define MAX_LUN    SCSI_NCR_MAX_LUN
#else
#define MAX_LUN    (1)
#endif

/*
**    Asynchronous pre-scaler (ns). Shall be 40
*/
 
#ifndef SCSI_NCR_MIN_ASYNC
#define SCSI_NCR_MIN_ASYNC (40)
#endif

/*
**    The maximum number of jobs scheduled for starting.
**    There should be one slot per target, and one slot
**    for each tag of each target in use.
**    The calculation below is actually quite silly ...
*/

#ifdef SCSI_NCR_CAN_QUEUE
#define MAX_START   (SCSI_NCR_CAN_QUEUE + 4)
#else
#define MAX_START   (MAX_TARGET + 7 * MAX_TAGS)
#endif

/*
**   We limit the max number of pending IO to 250.
**   since we donnot want to allocate more than 1 
**   PAGE for 'scripth'.
*/
#if     MAX_START > 250
#undef  MAX_START
#define MAX_START 250
#endif

/*
**    The maximum number of segments a transfer is split into.
**    We support up to 127 segments for both read and write.
**    The data scripts are broken into 2 sub-scripts.
**    80 (MAX_SCATTERL) segments are moved from a sub-script
**    in on-chip RAM. This makes data transfers shorter than 
**    80k (assuming 1k fs) as fast as possible.
*/

#define MAX_SCATTER (SCSI_NCR_MAX_SCATTER)

#if (MAX_SCATTER > 80)
#define MAX_SCATTERL    80
#define MAX_SCATTERH    (MAX_SCATTER - MAX_SCATTERL)
#else
#define MAX_SCATTERL    (MAX_SCATTER-1)
#define MAX_SCATTERH    1
#endif

/*
**      other
*/

#define NCR_SNOOP_TIMEOUT (1000000)

/*
**      Other definitions
*/

#define initverbose (driver_setup.verbose)
#define bootverbose (np->verbose)

/*==========================================================
**
**      Command control block states.
**
**==========================================================
*/

#define HS_IDLE         (0)
#define HS_BUSY         (1)
#define HS_NEGOTIATE    (2)     /* sync/wide data transfer*/
#define HS_DISCONNECT   (3)     /* Disconnected by target */

#define HS_DONEMASK     (0x80)
#define HS_COMPLETE     (4|HS_DONEMASK)
#define HS_SEL_TIMEOUT  (5|HS_DONEMASK) /* Selection timeout      */
#define HS_RESET        (6|HS_DONEMASK) /* SCSI reset             */
#define HS_ABORTED      (7|HS_DONEMASK) /* Transfer aborted       */
#define HS_TIMEOUT      (8|HS_DONEMASK) /* Software timeout       */
#define HS_FAIL         (9|HS_DONEMASK) /* SCSI or PCI bus errors */
#define HS_UNEXPECTED   (10|HS_DONEMASK)/* Unexpected disconnect  */

/*
**      Invalid host status values used by the SCRIPTS processor 
**      when the nexus is not fully identified.
**      Shall never appear in a CCB.
*/

#define HS_INVALMASK    (0x40)
#define HS_SELECTING    (0|HS_INVALMASK)
#define HS_IN_RESELECT  (1|HS_INVALMASK)
#define HS_STARTING     (2|HS_INVALMASK)

/*
**      Flags set by the SCRIPT processor for commands 
**      that have been skipped.
*/
#define HS_SKIPMASK     (0x20)

/*==========================================================
**
**      Software Interrupt Codes
**
**==========================================================
*/

#define SIR_BAD_STATUS          (1)
#define SIR_XXXXXXXXXX          (2)
#define SIR_NEGO_SYNC           (3)
#define SIR_NEGO_WIDE           (4)
#define SIR_NEGO_FAILED         (5)
#define SIR_NEGO_PROTO          (6)
#define SIR_REJECT_RECEIVED     (7)
#define SIR_REJECT_SENT         (8)
#define SIR_IGN_RESIDUE         (9)
#define SIR_MISSING_SAVE        (10)
#define SIR_RESEL_NO_MSG_IN     (11)
#define SIR_RESEL_NO_IDENTIFY   (12)
#define SIR_RESEL_BAD_LUN       (13)
#define SIR_RESEL_BAD_TARGET    (14)
#define SIR_RESEL_BAD_I_T_L     (15)
#define SIR_RESEL_BAD_I_T_L_Q   (16)
#define SIR_DONE_OVERFLOW       (17)
#define SIR_INTFLY              (18)
#define SIR_MAX                 (18)

/*==========================================================
**
**      Extended error codes.
**      xerr_status field of struct ccb.
**
**==========================================================
*/

#define XE_OK           (0)
#define XE_EXTRA_DATA   (1)     /* unexpected data phase */
#define XE_BAD_PHASE    (2)     /* illegal phase (4/5)   */

/*==========================================================
**
**      Negotiation status.
**      nego_status field       of struct ccb.
**
**==========================================================
*/

#define NS_NOCHANGE     (0)
#define NS_SYNC         (1)
#define NS_WIDE         (2)
#define NS_PPR          (4)

/*==========================================================
**
**      Misc.
**
**==========================================================
*/

#define CCB_MAGIC       (0xf2691ad2)

/*==========================================================
**
**      Declaration of structs.
**
**==========================================================
*/

static struct scsi_transport_template *ncr53c8xx_transport_template = NULL;

struct tcb;
struct lcb;
struct ccb;
struct ncb;
struct script;

struct link {
        ncrcmd  l_cmd;
        ncrcmd  l_paddr;
};

struct  usrcmd {
        u_long  target;
        u_long  lun;
        u_long  data;
        u_long  cmd;
};

#define UC_SETSYNC      10
#define UC_SETTAGS      11
#define UC_SETDEBUG     12
#define UC_SETORDER     13
#define UC_SETWIDE      14
#define UC_SETFLAG      15
#define UC_SETVERBOSE   17

#define UF_TRACE        (0x01)
#define UF_NODISC       (0x02)
#define UF_NOSCAN       (0x04)

/*========================================================================
**
**      Declaration of structs:         target control block
**
**========================================================================
*/
struct tcb {
        /*----------------------------------------------------------------
        **      During reselection the ncr jumps to this point with SFBR 
        **      set to the encoded target number with bit 7 set.
        **      if it's not this target, jump to the next.
        **
        **      JUMP  IF (SFBR != #target#), @(next tcb)
        **----------------------------------------------------------------
        */
        struct link   jump_tcb;

        /*----------------------------------------------------------------
        **      Load the actual values for the sxfer and the scntl3
        **      register (sync/wide mode).
        **
        **      SCR_COPY (1), @(sval field of this tcb), @(sxfer  register)
        **      SCR_COPY (1), @(wval field of this tcb), @(scntl3 register)
        **----------------------------------------------------------------
        */
        ncrcmd  getscr[6];

        /*----------------------------------------------------------------
        **      Get the IDENTIFY message and load the LUN to SFBR.
        **
        **      CALL, <RESEL_LUN>
        **----------------------------------------------------------------
        */
        struct link   call_lun;

        /*----------------------------------------------------------------
        **      Now look for the right lun.
        **
        **      For i = 0 to 3
        **              SCR_JUMP ^ IFTRUE(MASK(i, 3)), @(first lcb mod. i)
        **
        **      Recent chips will prefetch the 4 JUMPS using only 1 burst.
        **      It is kind of hashcoding.
        **----------------------------------------------------------------
        */
        struct link     jump_lcb[4];    /* JUMPs for reselection        */
        struct lcb *    lp[MAX_LUN];    /* The lcb's of this tcb        */

        /*----------------------------------------------------------------
        **      Pointer to the ccb used for negotiation.
        **      Prevent from starting a negotiation for all queued commands 
        **      when tagged command queuing is enabled.
        **----------------------------------------------------------------
        */
        struct ccb *   nego_cp;

        /*----------------------------------------------------------------
        **      statistical data
        **----------------------------------------------------------------
        */
        u_long  transfers;
        u_long  bytes;

        /*----------------------------------------------------------------
        **      negotiation of wide and synch transfer and device quirks.
        **----------------------------------------------------------------
        */
#ifdef SCSI_NCR_BIG_ENDIAN
/*0*/   u16     period;
/*2*/   u_char  sval;
/*3*/   u_char  minsync;
/*0*/   u_char  wval;
/*1*/   u_char  widedone;
/*2*/   u_char  quirks;
/*3*/   u_char  maxoffs;
#else
/*0*/   u_char  minsync;
/*1*/   u_char  sval;
/*2*/   u16     period;
/*0*/   u_char  maxoffs;
/*1*/   u_char  quirks;
/*2*/   u_char  widedone;
/*3*/   u_char  wval;
#endif

        /* User settable limits and options.  */
        u_char  usrsync;
        u_char  usrwide;
        u_char  usrtags;
        u_char  usrflag;
        struct scsi_target *starget;
};

/*========================================================================
**
**      Declaration of structs:         lun control block
**
**========================================================================
*/
struct lcb {
        /*----------------------------------------------------------------
        **      During reselection the ncr jumps to this point
        **      with SFBR set to the "Identify" message.
        **      if it's not this lun, jump to the next.
        **
        **      JUMP  IF (SFBR != #lun#), @(next lcb of this target)
        **
        **      It is this lun. Load TEMP with the nexus jumps table 
        **      address and jump to RESEL_TAG (or RESEL_NOTAG).
        **
        **              SCR_COPY (4), p_jump_ccb, TEMP,
        **              SCR_JUMP, <RESEL_TAG>
        **----------------------------------------------------------------
        */
        struct link     jump_lcb;
        ncrcmd          load_jump_ccb[3];
        struct link     jump_tag;
        ncrcmd          p_jump_ccb;     /* Jump table bus address       */

        /*----------------------------------------------------------------
        **      Jump table used by the script processor to directly jump 
        **      to the CCB corresponding to the reselected nexus.
        **      Address is allocated on 256 bytes boundary in order to 
        **      allow 8 bit calculation of the tag jump entry for up to 
        **      64 possible tags.
        **----------------------------------------------------------------
        */
        u32             jump_ccb_0;     /* Default table if no tags     */
        u32             *jump_ccb;      /* Virtual address              */

        /*----------------------------------------------------------------
        **      CCB queue management.
        **----------------------------------------------------------------
        */
        struct list_head free_ccbq;     /* Queue of available CCBs      */
        struct list_head busy_ccbq;     /* Queue of busy CCBs           */
        struct list_head wait_ccbq;     /* Queue of waiting for IO CCBs */
        struct list_head skip_ccbq;     /* Queue of skipped CCBs        */
        u_char          actccbs;        /* Number of allocated CCBs     */
        u_char          busyccbs;       /* CCBs busy for this lun       */
        u_char          queuedccbs;     /* CCBs queued to the controller*/
        u_char          queuedepth;     /* Queue depth for this lun     */
        u_char          scdev_depth;    /* SCSI device queue depth      */
        u_char          maxnxs;         /* Max possible nexuses         */

        /*----------------------------------------------------------------
        **      Control of tagged command queuing.
        **      Tags allocation is performed using a circular buffer.
        **      This avoids using a loop for tag allocation.
        **----------------------------------------------------------------
        */
        u_char          ia_tag;         /* Allocation index             */
        u_char          if_tag;         /* Freeing index                */
        u_char cb_tags[MAX_TAGS];       /* Circular tags buffer */
        u_char          usetags;        /* Command queuing is active    */
        u_char          maxtags;        /* Max nr of tags asked by user */
        u_char          numtags;        /* Current number of tags       */

        /*----------------------------------------------------------------
        **      QUEUE FULL control and ORDERED tag control.
        **----------------------------------------------------------------
        */
        /*----------------------------------------------------------------
        **      QUEUE FULL and ORDERED tag control.
        **----------------------------------------------------------------
        */
        u16             num_good;       /* Nr of GOOD since QUEUE FULL  */
        tagmap_t        tags_umap;      /* Used tags bitmap             */
        tagmap_t        tags_smap;      /* Tags in use at 'tag_stime'   */
        u_long          tags_stime;     /* Last time we set smap=umap   */
        struct ccb *    held_ccb;       /* CCB held for QUEUE FULL      */
};

/*========================================================================
**
**      Declaration of structs:     the launch script.
**
**========================================================================
**
**      It is part of the CCB and is called by the scripts processor to 
**      start or restart the data structure (nexus).
**      This 6 DWORDs mini script makes use of prefetching.
**
**------------------------------------------------------------------------
*/
struct launch {
        /*----------------------------------------------------------------
        **      SCR_COPY(4),    @(p_phys), @(dsa register)
        **      SCR_JUMP,       @(scheduler_point)
        **----------------------------------------------------------------
        */
        ncrcmd          setup_dsa[3];   /* Copy 'phys' address to dsa   */
        struct link     schedule;       /* Jump to scheduler point      */
        ncrcmd          p_phys;         /* 'phys' header bus address    */
};

/*========================================================================
**
**      Declaration of structs:     global HEADER.
**
**========================================================================
**
**      This substructure is copied from the ccb to a global address after 
**      selection (or reselection) and copied back before disconnect.
**
**      These fields are accessible to the script processor.
**
**------------------------------------------------------------------------
*/

struct head {
        /*----------------------------------------------------------------
        **      Saved data pointer.
        **      Points to the position in the script responsible for the
        **      actual transfer transfer of data.
        **      It's written after reception of a SAVE_DATA_POINTER message.
        **      The goalpointer points after the last transfer command.
        **----------------------------------------------------------------
        */
        u32             savep;
        u32             lastp;
        u32             goalp;

        /*----------------------------------------------------------------
        **      Alternate data pointer.
        **      They are copied back to savep/lastp/goalp by the SCRIPTS 
        **      when the direction is unknown and the device claims data out.
        **----------------------------------------------------------------
        */
        u32             wlastp;
        u32             wgoalp;

        /*----------------------------------------------------------------
        **      The virtual address of the ccb containing this header.
        **----------------------------------------------------------------
        */
        struct ccb *    cp;

        /*----------------------------------------------------------------
        **      Status fields.
        **----------------------------------------------------------------
        */
        u_char          scr_st[4];      /* script status                */
        u_char          status[4];      /* host status. must be the     */
                                        /*  last DWORD of the header.   */
};

/*
**      The status bytes are used by the host and the script processor.
**
**      The byte corresponding to the host_status must be stored in the 
**      last DWORD of the CCB header since it is used for command 
**      completion (ncr_wakeup()). Doing so, we are sure that the header 
**      has been entirely copied back to the CCB when the host_status is 
**      seen complete by the CPU.
**
**      The last four bytes (status[4]) are copied to the scratchb register
**      (declared as scr0..scr3 in ncr_reg.h) just after the select/reselect,
**      and copied back just after disconnecting.
**      Inside the script the XX_REG are used.
**
**      The first four bytes (scr_st[4]) are used inside the script by 
**      "COPY" commands.
**      Because source and destination must have the same alignment
**      in a DWORD, the fields HAVE to be at the chosen offsets.
**              xerr_st         0       (0x34)  scratcha
**              sync_st         1       (0x05)  sxfer
**              wide_st         3       (0x03)  scntl3
*/

/*
**      Last four bytes (script)
*/
#define  QU_REG scr0
#define  HS_REG scr1
#define  HS_PRT nc_scr1
#define  SS_REG scr2
#define  SS_PRT nc_scr2
#define  PS_REG scr3

/*
**      Last four bytes (host)
*/
#ifdef SCSI_NCR_BIG_ENDIAN
#define  actualquirks  phys.header.status[3]
#define  host_status   phys.header.status[2]
#define  scsi_status   phys.header.status[1]
#define  parity_status phys.header.status[0]
#else
#define  actualquirks  phys.header.status[0]
#define  host_status   phys.header.status[1]
#define  scsi_status   phys.header.status[2]
#define  parity_status phys.header.status[3]
#endif

/*
**      First four bytes (script)
*/
#define  xerr_st       header.scr_st[0]
#define  sync_st       header.scr_st[1]
#define  nego_st       header.scr_st[2]
#define  wide_st       header.scr_st[3]

/*
**      First four bytes (host)
*/
#define  xerr_status   phys.xerr_st
#define  nego_status   phys.nego_st

/*==========================================================
**
**      Declaration of structs:     Data structure block
**
**==========================================================
**
**      During execution of a ccb by the script processor,
**      the DSA (data structure address) register points
**      to this substructure of the ccb.
**      This substructure contains the header with
**      the script-processor-changeable data and
**      data blocks for the indirect move commands.
**
**----------------------------------------------------------
*/

struct dsb {

        /*
        **      Header.
        */

        struct head     header;

        /*
        **      Table data for Script
        */

        struct scr_tblsel  select;
        struct scr_tblmove smsg  ;
        struct scr_tblmove cmd   ;
        struct scr_tblmove sense ;
        struct scr_tblmove data[MAX_SCATTER];
};


/*========================================================================
**
**      Declaration of structs:     Command control block.
**
**========================================================================
*/
struct ccb {
        /*----------------------------------------------------------------
        **      This is the data structure which is pointed by the DSA 
        **      register when it is executed by the script processor.
        **      It must be the first entry because it contains the header 
        **      as first entry that must be cache line aligned.
        **----------------------------------------------------------------
        */
        struct dsb      phys;

        /*----------------------------------------------------------------
        **      Mini-script used at CCB execution start-up.
        **      Load the DSA with the data structure address (phys) and 
        **      jump to SELECT. Jump to CANCEL if CCB is to be canceled.
        **----------------------------------------------------------------
        */
        struct launch   start;

        /*----------------------------------------------------------------
        **      Mini-script used at CCB relection to restart the nexus.
        **      Load the DSA with the data structure address (phys) and 
        **      jump to RESEL_DSA. Jump to ABORT if CCB is to be aborted.
        **----------------------------------------------------------------
        */
        struct launch   restart;

        /*----------------------------------------------------------------
        **      If a data transfer phase is terminated too early
        **      (after reception of a message (i.e. DISCONNECT)),
        **      we have to prepare a mini script to transfer
        **      the rest of the data.
        **----------------------------------------------------------------
        */
        ncrcmd          patch[8];

        /*----------------------------------------------------------------
        **      The general SCSI driver provides a
        **      pointer to a control block.
        **----------------------------------------------------------------
        */
        struct scsi_cmnd        *cmd;           /* SCSI command                 */
        u_char          cdb_buf[16];    /* Copy of CDB                  */
        u_char          sense_buf[64];
        int             data_len;       /* Total data length            */

        /*----------------------------------------------------------------
        **      Message areas.
        **      We prepare a message to be sent after selection.
        **      We may use a second one if the command is rescheduled 
        **      due to GETCC or QFULL.
        **      Contents are IDENTIFY and SIMPLE_TAG.
        **      While negotiating sync or wide transfer,
        **      a SDTR or WDTR message is appended.
        **----------------------------------------------------------------
        */
        u_char          scsi_smsg [8];
        u_char          scsi_smsg2[8];

        /*----------------------------------------------------------------
        **      Other fields.
        **----------------------------------------------------------------
        */
        u_long          p_ccb;          /* BUS address of this CCB      */
        u_char          sensecmd[6];    /* Sense command                */
        u_char          tag;            /* Tag for this transfer        */
                                        /*  255 means no tag            */
        u_char          target;
        u_char          lun;
        u_char          queued;
        u_char          auto_sense;
        struct ccb *    link_ccb;       /* Host adapter CCB chain       */
        struct list_head link_ccbq;     /* Link to unit CCB queue       */
        u32             startp;         /* Initial data pointer         */
        u_long          magic;          /* Free / busy  CCB flag        */
};

#define CCB_PHYS(cp,lbl)        (cp->p_ccb + offsetof(struct ccb, lbl))


/*========================================================================
**
**      Declaration of structs:     NCR device descriptor
**
**========================================================================
*/
struct ncb {
        /*----------------------------------------------------------------
        **      The global header.
        **      It is accessible to both the host and the script processor.
        **      Must be cache line size aligned (32 for x86) in order to 
        **      allow cache line bursting when it is copied to/from CCB.
        **----------------------------------------------------------------
        */
        struct head     header;

        /*----------------------------------------------------------------
        **      CCBs management queues.
        **----------------------------------------------------------------
        */
        struct scsi_cmnd        *waiting_list;  /* Commands waiting for a CCB   */
                                        /*  when lcb is not allocated.  */
        struct scsi_cmnd        *done_list;     /* Commands waiting for done()  */
                                        /* callback to be invoked.      */ 
        spinlock_t      smp_lock;       /* Lock for SMP threading       */

        /*----------------------------------------------------------------
        **      Chip and controller identification.
        **----------------------------------------------------------------
        */
        int             unit;           /* Unit number                  */
        char            inst_name[16];  /* ncb instance name            */

        /*----------------------------------------------------------------
        **      Initial value of some IO register bits.
        **      These values are assumed to have been set by BIOS, and may 
        **      be used for probing adapter implementation differences.
        **----------------------------------------------------------------
        */
        u_char  sv_scntl0, sv_scntl3, sv_dmode, sv_dcntl, sv_ctest0, sv_ctest3,
                sv_ctest4, sv_ctest5, sv_gpcntl, sv_stest2, sv_stest4;

        /*----------------------------------------------------------------
        **      Actual initial value of IO register bits used by the 
        **      driver. They are loaded at initialisation according to  
        **      features that are to be enabled.
        **----------------------------------------------------------------
        */
        u_char  rv_scntl0, rv_scntl3, rv_dmode, rv_dcntl, rv_ctest0, rv_ctest3,
                rv_ctest4, rv_ctest5, rv_stest2;

        /*----------------------------------------------------------------
        **      Targets management.
        **      During reselection the ncr jumps to jump_tcb.
        **      The SFBR register is loaded with the encoded target id.
        **      For i = 0 to 3
        **              SCR_JUMP ^ IFTRUE(MASK(i, 3)), @(next tcb mod. i)
        **
        **      Recent chips will prefetch the 4 JUMPS using only 1 burst.
        **      It is kind of hashcoding.
        **----------------------------------------------------------------
        */
        struct link     jump_tcb[4];    /* JUMPs for reselection        */
        struct tcb  target[MAX_TARGET]; /* Target data                  */

        /*----------------------------------------------------------------
        **      Virtual and physical bus addresses of the chip.
        **----------------------------------------------------------------
        */
        void __iomem *vaddr;            /* Virtual and bus address of   */
        unsigned long   paddr;          /*  chip's IO registers.        */
        unsigned long   paddr2;         /* On-chip RAM bus address.     */
        volatile                        /* Pointer to volatile for      */
        struct ncr_reg  __iomem *reg;   /*  memory mapped IO.           */

        /*----------------------------------------------------------------
        **      SCRIPTS virtual and physical bus addresses.
        **      'script'  is loaded in the on-chip RAM if present.
        **      'scripth' stays in main memory.
        **----------------------------------------------------------------
        */
        struct script   *script0;       /* Copies of script and scripth */
        struct scripth  *scripth0;      /*  relocated for this ncb.     */
        struct scripth  *scripth;       /* Actual scripth virt. address */
        u_long          p_script;       /* Actual script and scripth    */
        u_long          p_scripth;      /*  bus addresses.              */

        /*----------------------------------------------------------------
        **      General controller parameters and configuration.
        **----------------------------------------------------------------
        */
        struct device   *dev;
        u_char          revision_id;    /* PCI device revision id       */
        u32             irq;            /* IRQ level                    */
        u32             features;       /* Chip features map            */
        u_char          myaddr;         /* SCSI id of the adapter       */
        u_char          maxburst;       /* log base 2 of dwords burst   */
        u_char          maxwide;        /* Maximum transfer width       */
        u_char          minsync;        /* Minimum sync period factor   */
        u_char          maxsync;        /* Maximum sync period factor   */
        u_char          maxoffs;        /* Max scsi offset              */
        u_char          multiplier;     /* Clock multiplier (1,2,4)     */
        u_char          clock_divn;     /* Number of clock divisors     */
        u_long          clock_khz;      /* SCSI clock frequency in KHz  */

        /*----------------------------------------------------------------
        **      Start queue management.
        **      It is filled up by the host processor and accessed by the 
        **      SCRIPTS processor in order to start SCSI commands.
        **----------------------------------------------------------------
        */
        u16             squeueput;      /* Next free slot of the queue  */
        u16             actccbs;        /* Number of allocated CCBs     */
        u16             queuedccbs;     /* Number of CCBs in start queue*/
        u16             queuedepth;     /* Start queue depth            */

        /*----------------------------------------------------------------
        **      Timeout handler.
        **----------------------------------------------------------------
        */
        struct timer_list timer;        /* Timer handler link header    */
        u_long          lasttime;
        u_long          settle_time;    /* Resetting the SCSI BUS       */

        /*----------------------------------------------------------------
        **      Debugging and profiling.
        **----------------------------------------------------------------
        */
        struct ncr_reg  regdump;        /* Register dump                */
        u_long          regtime;        /* Time it has been done        */

        /*----------------------------------------------------------------
        **      Miscellaneous buffers accessed by the scripts-processor.
        **      They shall be DWORD aligned, because they may be read or 
        **      written with a SCR_COPY script command.
        **----------------------------------------------------------------
        */
        u_char          msgout[8];      /* Buffer for MESSAGE OUT       */
        u_char          msgin [8];      /* Buffer for MESSAGE IN        */
        u32             lastmsg;        /* Last SCSI message sent       */
        u_char          scratch;        /* Scratch for SCSI receive     */

        /*----------------------------------------------------------------
        **      Miscellaneous configuration and status parameters.
        **----------------------------------------------------------------
        */
        u_char          disc;           /* Disconnection allowed        */
        u_char          scsi_mode;      /* Current SCSI BUS mode        */
        u_char          order;          /* Tag order to use             */
        u_char          verbose;        /* Verbosity for this controller*/
        int             ncr_cache;      /* Used for cache test at init. */
        u_long          p_ncb;          /* BUS address of this NCB      */

        /*----------------------------------------------------------------
        **      Command completion handling.
        **----------------------------------------------------------------
        */
#ifdef SCSI_NCR_CCB_DONE_SUPPORT
        struct ccb      *(ccb_done[MAX_DONE]);
        int             ccb_done_ic;
#endif
        /*----------------------------------------------------------------
        **      Fields that should be removed or changed.
        **----------------------------------------------------------------
        */
        struct ccb      *ccb;           /* Global CCB                   */
        struct usrcmd   user;           /* Command from user            */
        volatile u_char release_stage;  /* Synchronisation stage on release  */
};

#define NCB_SCRIPT_PHYS(np,lbl)  (np->p_script  + offsetof (struct script, lbl))
#define NCB_SCRIPTH_PHYS(np,lbl) (np->p_scripth + offsetof (struct scripth,lbl))

/*==========================================================
**
**
**      Script for NCR-Processor.
**
**      Use ncr_script_fill() to create the variable parts.
**      Use ncr_script_copy_and_bind() to make a copy and
**      bind to physical addresses.
**
**
**==========================================================
**
**      We have to know the offsets of all labels before
**      we reach them (for forward jumps).
**      Therefore we declare a struct here.
**      If you make changes inside the script,
**      DONT FORGET TO CHANGE THE LENGTHS HERE!
**
**----------------------------------------------------------
*/

/*
**      For HP Zalon/53c720 systems, the Zalon interface
**      between CPU and 53c720 does prefetches, which causes
**      problems with self modifying scripts.  The problem
**      is overcome by calling a dummy subroutine after each
**      modification, to force a refetch of the script on
**      return from the subroutine.
*/

#ifdef CONFIG_NCR53C8XX_PREFETCH
#define PREFETCH_FLUSH_CNT      2
#define PREFETCH_FLUSH          SCR_CALL, PADDRH (wait_dma),
#else
#define PREFETCH_FLUSH_CNT      0
#define PREFETCH_FLUSH
#endif

/*
**      Script fragments which are loaded into the on-chip RAM 
**      of 825A, 875 and 895 chips.
*/
struct script {
        ncrcmd  start           [  5];
        ncrcmd  startpos        [  1];
        ncrcmd  select          [  6];
        ncrcmd  select2         [  9 + PREFETCH_FLUSH_CNT];
        ncrcmd  loadpos         [  4];
        ncrcmd  send_ident      [  9];
        ncrcmd  prepare         [  6];
        ncrcmd  prepare2        [  7];
        ncrcmd  command         [  6];
        ncrcmd  dispatch        [ 32];
        ncrcmd  clrack          [  4];
        ncrcmd  no_data         [ 17];
        ncrcmd  status          [  8];
        ncrcmd  msg_in          [  2];
        ncrcmd  msg_in2         [ 16];
        ncrcmd  msg_bad         [  4];
        ncrcmd  setmsg          [  7];
        ncrcmd  cleanup         [  6];
        ncrcmd  complete        [  9];
        ncrcmd  cleanup_ok      [  8 + PREFETCH_FLUSH_CNT];
        ncrcmd  cleanup0        [  1];
#ifndef SCSI_NCR_CCB_DONE_SUPPORT
        ncrcmd  signal          [ 12];
#else
        ncrcmd  signal          [  9];
        ncrcmd  done_pos        [  1];
        ncrcmd  done_plug       [  2];
        ncrcmd  done_end        [  7];
#endif
        ncrcmd  save_dp         [  7];
        ncrcmd  restore_dp      [  5];
        ncrcmd  disconnect      [ 10];
        ncrcmd  msg_out         [  9];
        ncrcmd  msg_out_done    [  7];
        ncrcmd  idle            [  2];
        ncrcmd  reselect        [  8];
        ncrcmd  reselected      [  8];
        ncrcmd  resel_dsa       [  6 + PREFETCH_FLUSH_CNT];
        ncrcmd  loadpos1        [  4];
        ncrcmd  resel_lun       [  6];
        ncrcmd  resel_tag       [  6];
        ncrcmd  jump_to_nexus   [  4 + PREFETCH_FLUSH_CNT];
        ncrcmd  nexus_indirect  [  4];
        ncrcmd  resel_notag     [  4];
        ncrcmd  data_in         [MAX_SCATTERL * 4];
        ncrcmd  data_in2        [  4];
        ncrcmd  data_out        [MAX_SCATTERL * 4];
        ncrcmd  data_out2       [  4];
};

/*
**      Script fragments which stay in main memory for all chips.
*/
struct scripth {
        ncrcmd  tryloop         [MAX_START*2];
        ncrcmd  tryloop2        [  2];
#ifdef SCSI_NCR_CCB_DONE_SUPPORT
        ncrcmd  done_queue      [MAX_DONE*5];
        ncrcmd  done_queue2     [  2];
#endif
        ncrcmd  select_no_atn   [  8];
        ncrcmd  cancel          [  4];
        ncrcmd  skip            [  9 + PREFETCH_FLUSH_CNT];
        ncrcmd  skip2           [ 19];
        ncrcmd  par_err_data_in [  6];
        ncrcmd  par_err_other   [  4];
        ncrcmd  msg_reject      [  8];
        ncrcmd  msg_ign_residue [ 24];
        ncrcmd  msg_extended    [ 10];
        ncrcmd  msg_ext_2       [ 10];
        ncrcmd  msg_wdtr        [ 14];
        ncrcmd  send_wdtr       [  7];
        ncrcmd  msg_ext_3       [ 10];
        ncrcmd  msg_sdtr        [ 14];
        ncrcmd  send_sdtr       [  7];
        ncrcmd  nego_bad_phase  [  4];
        ncrcmd  msg_out_abort   [ 10];
        ncrcmd  hdata_in        [MAX_SCATTERH * 4];
        ncrcmd  hdata_in2       [  2];
        ncrcmd  hdata_out       [MAX_SCATTERH * 4];
        ncrcmd  hdata_out2      [  2];
        ncrcmd  reset           [  4];
        ncrcmd  aborttag        [  4];
        ncrcmd  abort           [  2];
        ncrcmd  abort_resel     [ 20];
        ncrcmd  resend_ident    [  4];
        ncrcmd  clratn_go_on    [  3];
        ncrcmd  nxtdsp_go_on    [  1];
        ncrcmd  sdata_in        [  8];
        ncrcmd  data_io         [ 18];
        ncrcmd  bad_identify    [ 12];
        ncrcmd  bad_i_t_l       [  4];
        ncrcmd  bad_i_t_l_q     [  4];
        ncrcmd  bad_target      [  8];
        ncrcmd  bad_status      [  8];
        ncrcmd  start_ram       [  4 + PREFETCH_FLUSH_CNT];
        ncrcmd  start_ram0      [  4];
        ncrcmd  sto_restart     [  5];
        ncrcmd  wait_dma        [  2];
        ncrcmd  snooptest       [  9];
        ncrcmd  snoopend        [  2];
};

/*==========================================================
**
**
**      Function headers.
**
**
**==========================================================
*/

static  void    ncr_alloc_ccb   (struct ncb *np, u_char tn, u_char ln);
static  void    ncr_complete    (struct ncb *np, struct ccb *cp);
static  void    ncr_exception   (struct ncb *np);
static  void    ncr_free_ccb    (struct ncb *np, struct ccb *cp);
static  void    ncr_init_ccb    (struct ncb *np, struct ccb *cp);
static  void    ncr_init_tcb    (struct ncb *np, u_char tn);
static  struct lcb *    ncr_alloc_lcb   (struct ncb *np, u_char tn, u_char ln);
static  struct lcb *    ncr_setup_lcb   (struct ncb *np, struct scsi_device *sdev);
static  void    ncr_getclock    (struct ncb *np, int mult);
static  void    ncr_selectclock (struct ncb *np, u_char scntl3);
static  struct ccb *ncr_get_ccb (struct ncb *np, struct scsi_cmnd *cmd);
static  void    ncr_chip_reset  (struct ncb *np, int delay);
static  void    ncr_init        (struct ncb *np, int reset, char * msg, u_long code);
static  int     ncr_int_sbmc    (struct ncb *np);
static  int     ncr_int_par     (struct ncb *np);
static  void    ncr_int_ma      (struct ncb *np);
static  void    ncr_int_sir     (struct ncb *np);
static  void    ncr_int_sto     (struct ncb *np);
static  void    ncr_negotiate   (struct ncb* np, struct tcb* tp);
static  int     ncr_prepare_nego(struct ncb *np, struct ccb *cp, u_char *msgptr);

static  void    ncr_script_copy_and_bind
                                (struct ncb *np, ncrcmd *src, ncrcmd *dst, int len);
static  void    ncr_script_fill (struct script * scr, struct scripth * scripth);
static  int     ncr_scatter     (struct ncb *np, struct ccb *cp, struct scsi_cmnd *cmd);
static  void    ncr_getsync     (struct ncb *np, u_char sfac, u_char *fakp, u_char *scntl3p);
static  void    ncr_setsync     (struct ncb *np, struct ccb *cp, u_char scntl3, u_char sxfer);
static  void    ncr_setup_tags  (struct ncb *np, struct scsi_device *sdev);
static  void    ncr_setwide     (struct ncb *np, struct ccb *cp, u_char wide, u_char ack);
static  int     ncr_snooptest   (struct ncb *np);
static  void    ncr_timeout     (struct ncb *np);
static  void    ncr_wakeup      (struct ncb *np, u_long code);
static  void    ncr_wakeup_done (struct ncb *np);
static  void    ncr_start_next_ccb (struct ncb *np, struct lcb * lp, int maxn);
static  void    ncr_put_start_queue(struct ncb *np, struct ccb *cp);

static void insert_into_waiting_list(struct ncb *np, struct scsi_cmnd *cmd);
static void process_waiting_list(struct ncb *np, int sts);

#define requeue_waiting_list(np) process_waiting_list((np), DID_OK)
#define reset_waiting_list(np) process_waiting_list((np), DID_RESET)

static inline char *ncr_name (struct ncb *np)
{
        return np->inst_name;
}


/*==========================================================
**
**
**      Scripts for NCR-Processor.
**
**      Use ncr_script_bind for binding to physical addresses.
**
**
**==========================================================
**
**      NADDR generates a reference to a field of the controller data.
**      PADDR generates a reference to another part of the script.
**      RADDR generates a reference to a script processor register.
**      FADDR generates a reference to a script processor register
**              with offset.
**
**----------------------------------------------------------
*/

#define RELOC_SOFTC     0x40000000
#define RELOC_LABEL     0x50000000
#define RELOC_REGISTER  0x60000000
#define RELOC_LABELH    0x80000000
#define RELOC_MASK      0xf0000000

#define NADDR(label)    (RELOC_SOFTC | offsetof(struct ncb, label))
#define PADDR(label)    (RELOC_LABEL | offsetof(struct script, label))
#define PADDRH(label)   (RELOC_LABELH | offsetof(struct scripth, label))
#define RADDR(label)    (RELOC_REGISTER | REG(label))
#define FADDR(label,ofs)(RELOC_REGISTER | ((REG(label))+(ofs)))


static  struct script script0 __initdata = {
/*--------------------------< START >-----------------------*/ {
        /*
        **      This NOP will be patched with LED ON
        **      SCR_REG_REG (gpreg, SCR_AND, 0xfe)
        */
        SCR_NO_OP,
                0,
        /*
        **      Clear SIGP.
        */
        SCR_FROM_REG (ctest2),
                0,
        /*
        **      Then jump to a certain point in tryloop.
        **      Due to the lack of indirect addressing the code
        **      is self modifying here.
        */
        SCR_JUMP,
}/*-------------------------< STARTPOS >--------------------*/,{
                PADDRH(tryloop),

}/*-------------------------< SELECT >----------------------*/,{
        /*
        **      DSA     contains the address of a scheduled
        **              data structure.
        **
        **      SCRATCHA contains the address of the script,
        **              which starts the next entry.
        **
        **      Set Initiator mode.
        **
        **      (Target mode is left as an exercise for the reader)
        */

        SCR_CLR (SCR_TRG),
                0,
        SCR_LOAD_REG (HS_REG, HS_SELECTING),
                0,

        /*
        **      And try to select this target.
        */
        SCR_SEL_TBL_ATN ^ offsetof (struct dsb, select),
                PADDR (reselect),

}/*-------------------------< SELECT2 >----------------------*/,{
        /*
        **      Now there are 4 possibilities:
        **
        **      (1) The ncr loses arbitration.
        **      This is ok, because it will try again,
        **      when the bus becomes idle.
        **      (But beware of the timeout function!)
        **
        **      (2) The ncr is reselected.
        **      Then the script processor takes the jump
        **      to the RESELECT label.
        **
        **      (3) The ncr wins arbitration.
        **      Then it will execute SCRIPTS instruction until 
        **      the next instruction that checks SCSI phase.
        **      Then will stop and wait for selection to be 
        **      complete or selection time-out to occur.
        **      As a result the SCRIPTS instructions until 
        **      LOADPOS + 2 should be executed in parallel with 
        **      the SCSI core performing selection.
        */

        /*
        **      The MESSAGE_REJECT problem seems to be due to a selection 
        **      timing problem.
        **      Wait immediately for the selection to complete. 
        **      (2.5x behaves so)
        */
        SCR_JUMPR ^ IFFALSE (WHEN (SCR_MSG_OUT)),
                0,

        /*
        **      Next time use the next slot.
        */
        SCR_COPY (4),
                RADDR (temp),
                PADDR (startpos),
        /*
        **      The ncr doesn't have an indirect load
        **      or store command. So we have to
        **      copy part of the control block to a
        **      fixed place, where we can access it.
        **
        **      We patch the address part of a
        **      COPY command with the DSA-register.
        */
        SCR_COPY_F (4),
                RADDR (dsa),
                PADDR (loadpos),
        /*
        **      Flush script prefetch if required
        */
        PREFETCH_FLUSH
        /*
        **      then we do the actual copy.
        */
        SCR_COPY (sizeof (struct head)),
        /*
        **      continued after the next label ...
        */
}/*-------------------------< LOADPOS >---------------------*/,{
                0,
                NADDR (header),
        /*
        **      Wait for the next phase or the selection
        **      to complete or time-out.
        */
        SCR_JUMP ^ IFFALSE (WHEN (SCR_MSG_OUT)),
                PADDR (prepare),

}/*-------------------------< SEND_IDENT >----------------------*/,{
        /*
        **      Selection complete.
        **      Send the IDENTIFY and SIMPLE_TAG messages
        **      (and the EXTENDED_SDTR message)
        */
        SCR_MOVE_TBL ^ SCR_MSG_OUT,
                offsetof (struct dsb, smsg),
        SCR_JUMP ^ IFTRUE (WHEN (SCR_MSG_OUT)),
                PADDRH (resend_ident),
        SCR_LOAD_REG (scratcha, 0x80),
                0,
        SCR_COPY (1),
                RADDR (scratcha),
                NADDR (lastmsg),
}/*-------------------------< PREPARE >----------------------*/,{
        /*
        **      load the savep (saved pointer) into
        **      the TEMP register (actual pointer)
        */
        SCR_COPY (4),
                NADDR (header.savep),
                RADDR (temp),
        /*
        **      Initialize the status registers
        */
        SCR_COPY (4),
                NADDR (header.status),
                RADDR (scr0),
}/*-------------------------< PREPARE2 >---------------------*/,{
        /*
        **      Initialize the msgout buffer with a NOOP message.
        */
        SCR_LOAD_REG (scratcha, NOP),
                0,
        SCR_COPY (1),
                RADDR (scratcha),
                NADDR (msgout),
        /*
        **      Anticipate the COMMAND phase.
        **      This is the normal case for initial selection.
        */
        SCR_JUMP ^ IFFALSE (WHEN (SCR_COMMAND)),
                PADDR (dispatch),

}/*-------------------------< COMMAND >--------------------*/,{
        /*
        **      ... and send the command
        */
        SCR_MOVE_TBL ^ SCR_COMMAND,
                offsetof (struct dsb, cmd),
        /*
        **      If status is still HS_NEGOTIATE, negotiation failed.
        **      We check this here, since we want to do that 
        **      only once.
        */
        SCR_FROM_REG (HS_REG),
                0,
        SCR_INT ^ IFTRUE (DATA (HS_NEGOTIATE)),
                SIR_NEGO_FAILED,

}/*-----------------------< DISPATCH >----------------------*/,{
        /*
        **      MSG_IN is the only phase that shall be 
        **      entered at least once for each (re)selection.
        **      So we test it first.
        */
        SCR_JUMP ^ IFTRUE (WHEN (SCR_MSG_IN)),
                PADDR (msg_in),

        SCR_RETURN ^ IFTRUE (IF (SCR_DATA_OUT)),
                0,
        /*
        **      DEL 397 - 53C875 Rev 3 - Part Number 609-0392410 - ITEM 4.
        **      Possible data corruption during Memory Write and Invalidate.
        **      This work-around resets the addressing logic prior to the 
        **      start of the first MOVE of a DATA IN phase.
        **      (See Documentation/scsi/ncr53c8xx.rst for more information)
        */
        SCR_JUMPR ^ IFFALSE (IF (SCR_DATA_IN)),
                20,
        SCR_COPY (4),
                RADDR (scratcha),
                RADDR (scratcha),
        SCR_RETURN,
                0,
        SCR_JUMP ^ IFTRUE (IF (SCR_STATUS)),
                PADDR (status),
        SCR_JUMP ^ IFTRUE (IF (SCR_COMMAND)),
                PADDR (command),
        SCR_JUMP ^ IFTRUE (IF (SCR_MSG_OUT)),
                PADDR (msg_out),
        /*
        **      Discard one illegal phase byte, if required.
        */
        SCR_LOAD_REG (scratcha, XE_BAD_PHASE),
                0,
        SCR_COPY (1),
                RADDR (scratcha),
                NADDR (xerr_st),
        SCR_JUMPR ^ IFFALSE (IF (SCR_ILG_OUT)),
                8,
        SCR_MOVE_ABS (1) ^ SCR_ILG_OUT,
                NADDR (scratch),
        SCR_JUMPR ^ IFFALSE (IF (SCR_ILG_IN)),
                8,
        SCR_MOVE_ABS (1) ^ SCR_ILG_IN,
                NADDR (scratch),
        SCR_JUMP,
                PADDR (dispatch),

}/*-------------------------< CLRACK >----------------------*/,{
        /*
        **      Terminate possible pending message phase.
        */
        SCR_CLR (SCR_ACK),
                0,
        SCR_JUMP,
                PADDR (dispatch),

}/*-------------------------< NO_DATA >--------------------*/,{
        /*
        **      The target wants to tranfer too much data
        **      or in the wrong direction.
        **      Remember that in extended error.
        */
        SCR_LOAD_REG (scratcha, XE_EXTRA_DATA),
                0,
        SCR_COPY (1),
                RADDR (scratcha),
                NADDR (xerr_st),
        /*
        **      Discard one data byte, if required.
        */
        SCR_JUMPR ^ IFFALSE (WHEN (SCR_DATA_OUT)),
                8,
        SCR_MOVE_ABS (1) ^ SCR_DATA_OUT,
                NADDR (scratch),
        SCR_JUMPR ^ IFFALSE (IF (SCR_DATA_IN)),
                8,
        SCR_MOVE_ABS (1) ^ SCR_DATA_IN,
                NADDR (scratch),
        /*
        **      .. and repeat as required.
        */
        SCR_CALL,
                PADDR (dispatch),
        SCR_JUMP,
                PADDR (no_data),

}/*-------------------------< STATUS >--------------------*/,{
        /*
        **      get the status
        */
        SCR_MOVE_ABS (1) ^ SCR_STATUS,
                NADDR (scratch),
        /*
        **      save status to scsi_status.
        **      mark as complete.
        */
        SCR_TO_REG (SS_REG),
                0,
        SCR_LOAD_REG (HS_REG, HS_COMPLETE),
                0,
        SCR_JUMP,
                PADDR (dispatch),
}/*-------------------------< MSG_IN >--------------------*/,{
        /*
        **      Get the first byte of the message
        **      and save it to SCRATCHA.
        **
        **      The script processor doesn't negate the
        **      ACK signal after this transfer.
        */
        SCR_MOVE_ABS (1) ^ SCR_MSG_IN,
                NADDR (msgin[0]),
}/*-------------------------< MSG_IN2 >--------------------*/,{
        /*
        **      Handle this message.
        */
        SCR_JUMP ^ IFTRUE (DATA (COMMAND_COMPLETE)),
                PADDR (complete),
        SCR_JUMP ^ IFTRUE (DATA (DISCONNECT)),
                PADDR (disconnect),
        SCR_JUMP ^ IFTRUE (DATA (SAVE_POINTERS)),
                PADDR (save_dp),
        SCR_JUMP ^ IFTRUE (DATA (RESTORE_POINTERS)),
                PADDR (restore_dp),
        SCR_JUMP ^ IFTRUE (DATA (EXTENDED_MESSAGE)),
                PADDRH (msg_extended),
        SCR_JUMP ^ IFTRUE (DATA (NOP)),
                PADDR (clrack),
        SCR_JUMP ^ IFTRUE (DATA (MESSAGE_REJECT)),
                PADDRH (msg_reject),
        SCR_JUMP ^ IFTRUE (DATA (IGNORE_WIDE_RESIDUE)),
                PADDRH (msg_ign_residue),
        /*
        **      Rest of the messages left as
        **      an exercise ...
        **
        **      Unimplemented messages:
        **      fall through to MSG_BAD.
        */
}/*-------------------------< MSG_BAD >------------------*/,{
        /*
        **      unimplemented message - reject it.
        */
        SCR_INT,
                SIR_REJECT_SENT,
        SCR_LOAD_REG (scratcha, MESSAGE_REJECT),
                0,
}/*-------------------------< SETMSG >----------------------*/,{
        SCR_COPY (1),
                RADDR (scratcha),
                NADDR (msgout),
        SCR_SET (SCR_ATN),
                0,
        SCR_JUMP,
                PADDR (clrack),
}/*-------------------------< CLEANUP >-------------------*/,{
        /*
        **      dsa:    Pointer to ccb
        **            or xxxxxxFF (no ccb)
        **
        **      HS_REG:   Host-Status (<>0!)
        */
        SCR_FROM_REG (dsa),
                0,
        SCR_JUMP ^ IFTRUE (DATA (0xff)),
                PADDR (start),
        /*
        **      dsa is valid.
        **      complete the cleanup.
        */
        SCR_JUMP,
                PADDR (cleanup_ok),

}/*-------------------------< COMPLETE >-----------------*/,{
        /*
        **      Complete message.
        **
        **      Copy TEMP register to LASTP in header.
        */
        SCR_COPY (4),
                RADDR (temp),
                NADDR (header.lastp),
        /*
        **      When we terminate the cycle by clearing ACK,
        **      the target may disconnect immediately.
        **
        **      We don't want to be told of an
        **      "unexpected disconnect",
        **      so we disable this feature.
        */
        SCR_REG_REG (scntl2, SCR_AND, 0x7f),
                0,
        /*
        **      Terminate cycle ...
        */
        SCR_CLR (SCR_ACK|SCR_ATN),
                0,
        /*
        **      ... and wait for the disconnect.
        */
        SCR_WAIT_DISC,
                0,
}/*-------------------------< CLEANUP_OK >----------------*/,{
        /*
        **      Save host status to header.
        */
        SCR_COPY (4),
                RADDR (scr0),
                NADDR (header.status),
        /*
        **      and copy back the header to the ccb.
        */
        SCR_COPY_F (4),
                RADDR (dsa),
                PADDR (cleanup0),
        /*
        **      Flush script prefetch if required
        */
        PREFETCH_FLUSH
        SCR_COPY (sizeof (struct head)),
                NADDR (header),
}/*-------------------------< CLEANUP0 >--------------------*/,{
                0,
}/*-------------------------< SIGNAL >----------------------*/,{
        /*
        **      if job not completed ...
        */
        SCR_FROM_REG (HS_REG),
                0,
        /*
        **      ... start the next command.
        */
        SCR_JUMP ^ IFTRUE (MASK (0, (HS_DONEMASK|HS_SKIPMASK))),
                PADDR(start),
        /*
        **      If command resulted in not GOOD status,
        **      call the C code if needed.
        */
        SCR_FROM_REG (SS_REG),
                0,
        SCR_CALL ^ IFFALSE (DATA (SAM_STAT_GOOD)),
                PADDRH (bad_status),

#ifndef SCSI_NCR_CCB_DONE_SUPPORT

        /*
        **      ... signal completion to the host
        */
        SCR_INT,
                SIR_INTFLY,
        /*
        **      Auf zu neuen Schandtaten!
        */
        SCR_JUMP,
                PADDR(start),

#else   /* defined SCSI_NCR_CCB_DONE_SUPPORT */

        /*
        **      ... signal completion to the host
        */
        SCR_JUMP,
}/*------------------------< DONE_POS >---------------------*/,{
                PADDRH (done_queue),
}/*------------------------< DONE_PLUG >--------------------*/,{
        SCR_INT,
                SIR_DONE_OVERFLOW,
}/*------------------------< DONE_END >---------------------*/,{
        SCR_INT,
                SIR_INTFLY,
        SCR_COPY (4),
                RADDR (temp),
                PADDR (done_pos),
        SCR_JUMP,
                PADDR (start),

#endif  /* SCSI_NCR_CCB_DONE_SUPPORT */

}/*-------------------------< SAVE_DP >------------------*/,{
        /*
        **      SAVE_DP message:
        **      Copy TEMP register to SAVEP in header.
        */
        SCR_COPY (4),
                RADDR (temp),
                NADDR (header.savep),
        SCR_CLR (SCR_ACK),
                0,
        SCR_JUMP,
                PADDR (dispatch),
}/*-------------------------< RESTORE_DP >---------------*/,{
        /*
        **      RESTORE_DP message:
        **      Copy SAVEP in header to TEMP register.
        */
        SCR_COPY (4),
                NADDR (header.savep),
                RADDR (temp),
        SCR_JUMP,
                PADDR (clrack),

}/*-------------------------< DISCONNECT >---------------*/,{
        /*
        **      DISCONNECTing  ...
        **
        **      disable the "unexpected disconnect" feature,
        **      and remove the ACK signal.
        */
        SCR_REG_REG (scntl2, SCR_AND, 0x7f),
                0,
        SCR_CLR (SCR_ACK|SCR_ATN),
                0,
        /*
        **      Wait for the disconnect.
        */
        SCR_WAIT_DISC,
                0,
        /*
        **      Status is: DISCONNECTED.
        */
        SCR_LOAD_REG (HS_REG, HS_DISCONNECT),
                0,
        SCR_JUMP,
                PADDR (cleanup_ok),

}/*-------------------------< MSG_OUT >-------------------*/,{
        /*
        **      The target requests a message.
        */
        SCR_MOVE_ABS (1) ^ SCR_MSG_OUT,
                NADDR (msgout),
        SCR_COPY (1),
                NADDR (msgout),
                NADDR (lastmsg),
        /*
        **      If it was no ABORT message ...
        */
        SCR_JUMP ^ IFTRUE (DATA (ABORT_TASK_SET)),
                PADDRH (msg_out_abort),
        /*
        **      ... wait for the next phase
        **      if it's a message out, send it again, ...
        */
        SCR_JUMP ^ IFTRUE (WHEN (SCR_MSG_OUT)),
                PADDR (msg_out),
}/*-------------------------< MSG_OUT_DONE >--------------*/,{
        /*
        **      ... else clear the message ...
        */
        SCR_LOAD_REG (scratcha, NOP),
                0,
        SCR_COPY (4),
                RADDR (scratcha),
                NADDR (msgout),
        /*
        **      ... and process the next phase
        */
        SCR_JUMP,
                PADDR (dispatch),
}/*-------------------------< IDLE >------------------------*/,{
        /*
        **      Nothing to do?
        **      Wait for reselect.
        **      This NOP will be patched with LED OFF
        **      SCR_REG_REG (gpreg, SCR_OR, 0x01)
        */
        SCR_NO_OP,
                0,
}/*-------------------------< RESELECT >--------------------*/,{
        /*
        **      make the DSA invalid.
        */
        SCR_LOAD_REG (dsa, 0xff),
                0,
        SCR_CLR (SCR_TRG),
                0,
        SCR_LOAD_REG (HS_REG, HS_IN_RESELECT),
                0,
        /*
        **      Sleep waiting for a reselection.
        **      If SIGP is set, special treatment.
        **
        **      Zu allem bereit ..
        */
        SCR_WAIT_RESEL,
                PADDR(start),
}/*-------------------------< RESELECTED >------------------*/,{
        /*
        **      This NOP will be patched with LED ON
        **      SCR_REG_REG (gpreg, SCR_AND, 0xfe)
        */
        SCR_NO_OP,
                0,
        /*
        **      ... zu nichts zu gebrauchen ?
        **
        **      load the target id into the SFBR
        **      and jump to the control block.
        **
        **      Look at the declarations of
        **      - struct ncb
        **      - struct tcb
        **      - struct lcb
        **      - struct ccb
        **      to understand what's going on.
        */
        SCR_REG_SFBR (ssid, SCR_AND, 0x8F),
                0,
        SCR_TO_REG (sdid),
                0,
        SCR_JUMP,
                NADDR (jump_tcb),

}/*-------------------------< RESEL_DSA >-------------------*/,{
        /*
        **      Ack the IDENTIFY or TAG previously received.
        */
        SCR_CLR (SCR_ACK),
                0,
        /*
        **      The ncr doesn't have an indirect load
        **      or store command. So we have to
        **      copy part of the control block to a
        **      fixed place, where we can access it.
        **
        **      We patch the address part of a
        **      COPY command with the DSA-register.
        */
        SCR_COPY_F (4),
                RADDR (dsa),
                PADDR (loadpos1),
        /*
        **      Flush script prefetch if required
        */
        PREFETCH_FLUSH
        /*
        **      then we do the actual copy.
        */
        SCR_COPY (sizeof (struct head)),
        /*
        **      continued after the next label ...
        */

}/*-------------------------< LOADPOS1 >-------------------*/,{
                0,
                NADDR (header),
        /*
        **      The DSA contains the data structure address.
        */
        SCR_JUMP,
                PADDR (prepare),

}/*-------------------------< RESEL_LUN >-------------------*/,{
        /*
        **      come back to this point
        **      to get an IDENTIFY message
        **      Wait for a msg_in phase.
        */
        SCR_INT ^ IFFALSE (WHEN (SCR_MSG_IN)),
                SIR_RESEL_NO_MSG_IN,
        /*
        **      message phase.
        **      Read the data directly from the BUS DATA lines.
        **      This helps to support very old SCSI devices that 
        **      may reselect without sending an IDENTIFY.
        */
        SCR_FROM_REG (sbdl),
                0,
        /*
        **      It should be an Identify message.
        */
        SCR_RETURN,
                0,
}/*-------------------------< RESEL_TAG >-------------------*/,{
        /*
        **      Read IDENTIFY + SIMPLE + TAG using a single MOVE.
        **      Aggressive optimization, is'nt it?
        **      No need to test the SIMPLE TAG message, since the 
        **      driver only supports conformant devices for tags. ;-)
        */
        SCR_MOVE_ABS (3) ^ SCR_MSG_IN,
                NADDR (msgin),
        /*
        **      Read the TAG from the SIDL.
        **      Still an aggressive optimization. ;-)
        **      Compute the CCB indirect jump address which 
        **      is (#TAG*2 & 0xfc) due to tag numbering using 
        **      1,3,5..MAXTAGS*2+1 actual values.
        */
        SCR_REG_SFBR (sidl, SCR_SHL, 0),
                0,
        SCR_SFBR_REG (temp, SCR_AND, 0xfc),
                0,
}/*-------------------------< JUMP_TO_NEXUS >-------------------*/,{
        SCR_COPY_F (4),
                RADDR (temp),
                PADDR (nexus_indirect),
        /*
        **      Flush script prefetch if required
        */
        PREFETCH_FLUSH
        SCR_COPY (4),
}/*-------------------------< NEXUS_INDIRECT >-------------------*/,{
                0,
                RADDR (temp),
        SCR_RETURN,
                0,
}/*-------------------------< RESEL_NOTAG >-------------------*/,{
        /*
        **      No tag expected.
        **      Read an throw away the IDENTIFY.
        */
        SCR_MOVE_ABS (1) ^ SCR_MSG_IN,
                NADDR (msgin),
        SCR_JUMP,
                PADDR (jump_to_nexus),
}/*-------------------------< DATA_IN >--------------------*/,{
/*
**      Because the size depends on the
**      #define MAX_SCATTERL parameter,
**      it is filled in at runtime.
**
**  ##===========< i=0; i<MAX_SCATTERL >=========
**  ||  SCR_CALL ^ IFFALSE (WHEN (SCR_DATA_IN)),
**  ||          PADDR (dispatch),
**  ||  SCR_MOVE_TBL ^ SCR_DATA_IN,
**  ||          offsetof (struct dsb, data[ i]),
**  ##==========================================
**
**---------------------------------------------------------
*/
0
}/*-------------------------< DATA_IN2 >-------------------*/,{
        SCR_CALL,
                PADDR (dispatch),
        SCR_JUMP,
                PADDR (no_data),
}/*-------------------------< DATA_OUT >--------------------*/,{
/*
**      Because the size depends on the
**      #define MAX_SCATTERL parameter,
**      it is filled in at runtime.
**
**  ##===========< i=0; i<MAX_SCATTERL >=========
**  ||  SCR_CALL ^ IFFALSE (WHEN (SCR_DATA_OUT)),
**  ||          PADDR (dispatch),
**  ||  SCR_MOVE_TBL ^ SCR_DATA_OUT,
**  ||          offsetof (struct dsb, data[ i]),
**  ##==========================================
**
**---------------------------------------------------------
*/
0
}/*-------------------------< DATA_OUT2 >-------------------*/,{
        SCR_CALL,
                PADDR (dispatch),
        SCR_JUMP,
                PADDR (no_data),
}/*--------------------------------------------------------*/
};

static  struct scripth scripth0 __initdata = {
/*-------------------------< TRYLOOP >---------------------*/{
/*
**      Start the next entry.
**      Called addresses point to the launch script in the CCB.
**      They are patched by the main processor.
**
**      Because the size depends on the
**      #define MAX_START parameter, it is filled
**      in at runtime.
**
**-----------------------------------------------------------
**
**  ##===========< I=0; i<MAX_START >===========
**  ||  SCR_CALL,
**  ||          PADDR (idle),
**  ##==========================================
**
**-----------------------------------------------------------
*/
0
}/*------------------------< TRYLOOP2 >---------------------*/,{
        SCR_JUMP,
                PADDRH(tryloop),

#ifdef SCSI_NCR_CCB_DONE_SUPPORT

}/*------------------------< DONE_QUEUE >-------------------*/,{
/*
**      Copy the CCB address to the next done entry.
**      Because the size depends on the
**      #define MAX_DONE parameter, it is filled
**      in at runtime.
**
**-----------------------------------------------------------
**
**  ##===========< I=0; i<MAX_DONE >===========
**  ||  SCR_COPY (sizeof(struct ccb *),
**  ||          NADDR (header.cp),
**  ||          NADDR (ccb_done[i]),
**  ||  SCR_CALL,
**  ||          PADDR (done_end),
**  ##==========================================
**
**-----------------------------------------------------------
*/
0
}/*------------------------< DONE_QUEUE2 >------------------*/,{
        SCR_JUMP,
                PADDRH (done_queue),

#endif /* SCSI_NCR_CCB_DONE_SUPPORT */
}/*------------------------< SELECT_NO_ATN >-----------------*/,{
        /*
        **      Set Initiator mode.
        **      And try to select this target without ATN.
        */

        SCR_CLR (SCR_TRG),
                0,
        SCR_LOAD_REG (HS_REG, HS_SELECTING),
                0,
        SCR_SEL_TBL ^ offsetof (struct dsb, select),
                PADDR (reselect),
        SCR_JUMP,
                PADDR (select2),

}/*-------------------------< CANCEL >------------------------*/,{

        SCR_LOAD_REG (scratcha, HS_ABORTED),
                0,
        SCR_JUMPR,
                8,
}/*-------------------------< SKIP >------------------------*/,{
        SCR_LOAD_REG (scratcha, 0),
                0,
        /*
        **      This entry has been canceled.
        **      Next time use the next slot.
        */
        SCR_COPY (4),
                RADDR (temp),
                PADDR (startpos),
        /*
        **      The ncr doesn't have an indirect load
        **      or store command. So we have to
        **      copy part of the control block to a
        **      fixed place, where we can access it.
        **
        **      We patch the address part of a
        **      COPY command with the DSA-register.
        */
        SCR_COPY_F (4),
                RADDR (dsa),
                PADDRH (skip2),
        /*
        **      Flush script prefetch if required
        */
        PREFETCH_FLUSH
        /*
        **      then we do the actual copy.
        */
        SCR_COPY (sizeof (struct head)),
        /*
        **      continued after the next label ...
        */
}/*-------------------------< SKIP2 >---------------------*/,{
                0,
                NADDR (header),
        /*
        **      Initialize the status registers
        */
        SCR_COPY (4),
                NADDR (header.status),
                RADDR (scr0),
        /*
        **      Force host status.
        */
        SCR_FROM_REG (scratcha),
                0,
        SCR_JUMPR ^ IFFALSE (MASK (0, HS_DONEMASK)),
                16,
        SCR_REG_REG (HS_REG, SCR_OR, HS_SKIPMASK),
                0,
        SCR_JUMPR,
                8,
        SCR_TO_REG (HS_REG),
                0,
        SCR_LOAD_REG (SS_REG, SAM_STAT_GOOD),
                0,
        SCR_JUMP,
                PADDR (cleanup_ok),

},/*-------------------------< PAR_ERR_DATA_IN >---------------*/{
        /*
        **      Ignore all data in byte, until next phase
        */
        SCR_JUMP ^ IFFALSE (WHEN (SCR_DATA_IN)),
                PADDRH (par_err_other),
        SCR_MOVE_ABS (1) ^ SCR_DATA_IN,
                NADDR (scratch),
        SCR_JUMPR,
                -24,
},/*-------------------------< PAR_ERR_OTHER >------------------*/{
        /*
        **      count it.
        */
        SCR_REG_REG (PS_REG, SCR_ADD, 0x01),
                0,
        /*
        **      jump to dispatcher.
        */
        SCR_JUMP,
                PADDR (dispatch),
}/*-------------------------< MSG_REJECT >---------------*/,{
        /*
        **      If a negotiation was in progress,
        **      negotiation failed.
        **      Otherwise, let the C code print 
        **      some message.
        */
        SCR_FROM_REG (HS_REG),
                0,
        SCR_INT ^ IFFALSE (DATA (HS_NEGOTIATE)),
                SIR_REJECT_RECEIVED,
        SCR_INT ^ IFTRUE (DATA (HS_NEGOTIATE)),
                SIR_NEGO_FAILED,
        SCR_JUMP,
                PADDR (clrack),

}/*-------------------------< MSG_IGN_RESIDUE >----------*/,{
        /*
        **      Terminate cycle
        */
        SCR_CLR (SCR_ACK),
                0,
        SCR_JUMP ^ IFFALSE (WHEN (SCR_MSG_IN)),
                PADDR (dispatch),
        /*
        **      get residue size.
        */
        SCR_MOVE_ABS (1) ^ SCR_MSG_IN,
                NADDR (msgin[1]),
        /*
        **      Size is 0 .. ignore message.
        */
        SCR_JUMP ^ IFTRUE (DATA (0)),
                PADDR (clrack),
        /*
        **      Size is not 1 .. have to interrupt.
        */
        SCR_JUMPR ^ IFFALSE (DATA (1)),
                40,
        /*
        **      Check for residue byte in swide register
        */
        SCR_FROM_REG (scntl2),
                0,
        SCR_JUMPR ^ IFFALSE (MASK (WSR, WSR)),
                16,
        /*
        **      There IS data in the swide register.
        **      Discard it.
        */
        SCR_REG_REG (scntl2, SCR_OR, WSR),
                0,
        SCR_JUMP,
                PADDR (clrack),
        /*
        **      Load again the size to the sfbr register.
        */
        SCR_FROM_REG (scratcha),
                0,
        SCR_INT,
                SIR_IGN_RESIDUE,
        SCR_JUMP,
                PADDR (clrack),

}/*-------------------------< MSG_EXTENDED >-------------*/,{
        /*
        **      Terminate cycle
        */
        SCR_CLR (SCR_ACK),
                0,
        SCR_JUMP ^ IFFALSE (WHEN (SCR_MSG_IN)),
                PADDR (dispatch),
        /*
        **      get length.
        */
        SCR_MOVE_ABS (1) ^ SCR_MSG_IN,
                NADDR (msgin[1]),
        /*
        */
        SCR_JUMP ^ IFTRUE (DATA (3)),
                PADDRH (msg_ext_3),
        SCR_JUMP ^ IFFALSE (DATA (2)),
                PADDR (msg_bad),
}/*-------------------------< MSG_EXT_2 >----------------*/,{
        SCR_CLR (SCR_ACK),
                0,
        SCR_JUMP ^ IFFALSE (WHEN (SCR_MSG_IN)),
                PADDR (dispatch),
        /*
        **      get extended message code.
        */
        SCR_MOVE_ABS (1) ^ SCR_MSG_IN,
                NADDR (msgin[2]),
        SCR_JUMP ^ IFTRUE (DATA (EXTENDED_WDTR)),
                PADDRH (msg_wdtr),
        /*
        **      unknown extended message
        */
        SCR_JUMP,
                PADDR (msg_bad)
}/*-------------------------< MSG_WDTR >-----------------*/,{
        SCR_CLR (SCR_ACK),
                0,
        SCR_JUMP ^ IFFALSE (WHEN (SCR_MSG_IN)),
                PADDR (dispatch),
        /*
        **      get data bus width
        */
        SCR_MOVE_ABS (1) ^ SCR_MSG_IN,
                NADDR (msgin[3]),
        /*
        **      let the host do the real work.
        */
        SCR_INT,
                SIR_NEGO_WIDE,
        /*
        **      let the target fetch our answer.
        */
        SCR_SET (SCR_ATN),
                0,
        SCR_CLR (SCR_ACK),
                0,
        SCR_JUMP ^ IFFALSE (WHEN (SCR_MSG_OUT)),
                PADDRH (nego_bad_phase),

}/*-------------------------< SEND_WDTR >----------------*/,{
        /*
        **      Send the EXTENDED_WDTR
        */
        SCR_MOVE_ABS (4) ^ SCR_MSG_OUT,
                NADDR (msgout),
        SCR_COPY (1),
                NADDR (msgout),
                NADDR (lastmsg),
        SCR_JUMP,
                PADDR (msg_out_done),

}/*-------------------------< MSG_EXT_3 >----------------*/,{
        SCR_CLR (SCR_ACK),
                0,
        SCR_JUMP ^ IFFALSE (WHEN (SCR_MSG_IN)),
                PADDR (dispatch),
        /*
        **      get extended message code.
        */
        SCR_MOVE_ABS (1) ^ SCR_MSG_IN,
                NADDR (msgin[2]),
        SCR_JUMP ^ IFTRUE (DATA (EXTENDED_SDTR)),
                PADDRH (msg_sdtr),
        /*
        **      unknown extended message
        */
        SCR_JUMP,
                PADDR (msg_bad)

}/*-------------------------< MSG_SDTR >-----------------*/,{
        SCR_CLR (SCR_ACK),
                0,
        SCR_JUMP ^ IFFALSE (WHEN (SCR_MSG_IN)),
                PADDR (dispatch),
        /*
        **      get period and offset
        */
        SCR_MOVE_ABS (2) ^ SCR_MSG_IN,
                NADDR (msgin[3]),
        /*
        **      let the host do the real work.
        */
        SCR_INT,
                SIR_NEGO_SYNC,
        /*
        **      let the target fetch our answer.
        */
        SCR_SET (SCR_ATN),
                0,
        SCR_CLR (SCR_ACK),
                0,
        SCR_JUMP ^ IFFALSE (WHEN (SCR_MSG_OUT)),
                PADDRH (nego_bad_phase),

}/*-------------------------< SEND_SDTR >-------------*/,{
        /*
        **      Send the EXTENDED_SDTR
        */
        SCR_MOVE_ABS (5) ^ SCR_MSG_OUT,
                NADDR (msgout),
        SCR_COPY (1),
                NADDR (msgout),
                NADDR (lastmsg),
        SCR_JUMP,
                PADDR (msg_out_done),

}/*-------------------------< NEGO_BAD_PHASE >------------*/,{
        SCR_INT,
                SIR_NEGO_PROTO,
        SCR_JUMP,
                PADDR (dispatch),

}/*-------------------------< MSG_OUT_ABORT >-------------*/,{
        /*
        **      After ABORT message,
        **
        **      expect an immediate disconnect, ...
        */
        SCR_REG_REG (scntl2, SCR_AND, 0x7f),
                0,
        SCR_CLR (SCR_ACK|SCR_ATN),
                0,
        SCR_WAIT_DISC,
                0,
        /*
        **      ... and set the status to "ABORTED"
        */
        SCR_LOAD_REG (HS_REG, HS_ABORTED),
                0,
        SCR_JUMP,
                PADDR (cleanup),

}/*-------------------------< HDATA_IN >-------------------*/,{
/*
**      Because the size depends on the
**      #define MAX_SCATTERH parameter,
**      it is filled in at runtime.
**
**  ##==< i=MAX_SCATTERL; i<MAX_SCATTERL+MAX_SCATTERH >==
**  ||  SCR_CALL ^ IFFALSE (WHEN (SCR_DATA_IN)),
**  ||          PADDR (dispatch),
**  ||  SCR_MOVE_TBL ^ SCR_DATA_IN,
**  ||          offsetof (struct dsb, data[ i]),
**  ##===================================================
**
**---------------------------------------------------------
*/
0
}/*-------------------------< HDATA_IN2 >------------------*/,{
        SCR_JUMP,
                PADDR (data_in),

}/*-------------------------< HDATA_OUT >-------------------*/,{
/*
**      Because the size depends on the
**      #define MAX_SCATTERH parameter,
**      it is filled in at runtime.
**
**  ##==< i=MAX_SCATTERL; i<MAX_SCATTERL+MAX_SCATTERH >==
**  ||  SCR_CALL ^ IFFALSE (WHEN (SCR_DATA_OUT)),
**  ||          PADDR (dispatch),
**  ||  SCR_MOVE_TBL ^ SCR_DATA_OUT,
**  ||          offsetof (struct dsb, data[ i]),
**  ##===================================================
**
**---------------------------------------------------------
*/
0
}/*-------------------------< HDATA_OUT2 >------------------*/,{
        SCR_JUMP,
                PADDR (data_out),

}/*-------------------------< RESET >----------------------*/,{
        /*
        **      Send a TARGET_RESET message if bad IDENTIFY 
        **      received on reselection.
        */
        SCR_LOAD_REG (scratcha, ABORT_TASK),
                0,
        SCR_JUMP,
                PADDRH (abort_resel),
}/*-------------------------< ABORTTAG >-------------------*/,{
        /*
        **      Abort a wrong tag received on reselection.
        */
        SCR_LOAD_REG (scratcha, ABORT_TASK),
                0,
        SCR_JUMP,
                PADDRH (abort_resel),
}/*-------------------------< ABORT >----------------------*/,{
        /*
        **      Abort a reselection when no active CCB.
        */
        SCR_LOAD_REG (scratcha, ABORT_TASK_SET),
                0,
}/*-------------------------< ABORT_RESEL >----------------*/,{
        SCR_COPY (1),
                RADDR (scratcha),
                NADDR (msgout),
        SCR_SET (SCR_ATN),
                0,
        SCR_CLR (SCR_ACK),
                0,
        /*
        **      and send it.
        **      we expect an immediate disconnect
        */
        SCR_REG_REG (scntl2, SCR_AND, 0x7f),
                0,
        SCR_MOVE_ABS (1) ^ SCR_MSG_OUT,
                NADDR (msgout),
        SCR_COPY (1),
                NADDR (msgout),
                NADDR (lastmsg),
        SCR_CLR (SCR_ACK|SCR_ATN),
                0,
        SCR_WAIT_DISC,
                0,
        SCR_JUMP,
                PADDR (start),
}/*-------------------------< RESEND_IDENT >-------------------*/,{
        /*
        **      The target stays in MSG OUT phase after having acked 
        **      Identify [+ Tag [+ Extended message ]]. Targets shall
        **      behave this way on parity error.
        **      We must send it again all the messages.
        */
        SCR_SET (SCR_ATN), /* Shall be asserted 2 deskew delays before the  */
                0,         /* 1rst ACK = 90 ns. Hope the NCR is'nt too fast */
        SCR_JUMP,
                PADDR (send_ident),
}/*-------------------------< CLRATN_GO_ON >-------------------*/,{
        SCR_CLR (SCR_ATN),
                0,
        SCR_JUMP,
}/*-------------------------< NXTDSP_GO_ON >-------------------*/,{
                0,
}/*-------------------------< SDATA_IN >-------------------*/,{
        SCR_CALL ^ IFFALSE (WHEN (SCR_DATA_IN)),
                PADDR (dispatch),
        SCR_MOVE_TBL ^ SCR_DATA_IN,
                offsetof (struct dsb, sense),
        SCR_CALL,
                PADDR (dispatch),
        SCR_JUMP,
                PADDR (no_data),
}/*-------------------------< DATA_IO >--------------------*/,{
        /*
        **      We jump here if the data direction was unknown at the 
        **      time we had to queue the command to the scripts processor.
        **      Pointers had been set as follow in this situation:
        **        savep   -->   DATA_IO
        **        lastp   -->   start pointer when DATA_IN
        **        goalp   -->   goal  pointer when DATA_IN
        **        wlastp  -->   start pointer when DATA_OUT
        **        wgoalp  -->   goal  pointer when DATA_OUT
        **      This script sets savep/lastp/goalp according to the 
        **      direction chosen by the target.
        */
        SCR_JUMPR ^ IFTRUE (WHEN (SCR_DATA_OUT)),
                32,
        /*
        **      Direction is DATA IN.
        **      Warning: we jump here, even when phase is DATA OUT.
        */
        SCR_COPY (4),
                NADDR (header.lastp),
                NADDR (header.savep),

        /*
        **      Jump to the SCRIPTS according to actual direction.
        */
        SCR_COPY (4),
                NADDR (header.savep),
                RADDR (temp),
        SCR_RETURN,
                0,
        /*
        **      Direction is DATA OUT.
        */
        SCR_COPY (4),
                NADDR (header.wlastp),
                NADDR (header.lastp),
        SCR_COPY (4),
                NADDR (header.wgoalp),
                NADDR (header.goalp),
        SCR_JUMPR,
                -64,
}/*-------------------------< BAD_IDENTIFY >---------------*/,{
        /*
        **      If message phase but not an IDENTIFY,
        **      get some help from the C code.
        **      Old SCSI device may behave so.
        */
        SCR_JUMPR ^ IFTRUE (MASK (0x80, 0x80)),
                16,
        SCR_INT,
                SIR_RESEL_NO_IDENTIFY,
        SCR_JUMP,
                PADDRH (reset),
        /*
        **      Message is an IDENTIFY, but lun is unknown.
        **      Read the message, since we got it directly 
        **      from the SCSI BUS data lines.
        **      Signal problem to C code for logging the event.
        **      Send an ABORT_TASK_SET to clear all pending tasks.
        */
        SCR_INT,
                SIR_RESEL_BAD_LUN,
        SCR_MOVE_ABS (1) ^ SCR_MSG_IN,
                NADDR (msgin),
        SCR_JUMP,
                PADDRH (abort),
}/*-------------------------< BAD_I_T_L >------------------*/,{
        /*
        **      We donnot have a task for that I_T_L.
        **      Signal problem to C code for logging the event.
        **      Send an ABORT_TASK_SET message.
        */
        SCR_INT,
                SIR_RESEL_BAD_I_T_L,
        SCR_JUMP,
                PADDRH (abort),
}/*-------------------------< BAD_I_T_L_Q >----------------*/,{
        /*
        **      We donnot have a task that matches the tag.
        **      Signal problem to C code for logging the event.
        **      Send an ABORT_TASK message.
        */
        SCR_INT,
                SIR_RESEL_BAD_I_T_L_Q,
        SCR_JUMP,
                PADDRH (aborttag),
}/*-------------------------< BAD_TARGET >-----------------*/,{
        /*
        **      We donnot know the target that reselected us.
        **      Grab the first message if any (IDENTIFY).
        **      Signal problem to C code for logging the event.
        **      TARGET_RESET message.
        */
        SCR_INT,
                SIR_RESEL_BAD_TARGET,
        SCR_JUMPR ^ IFFALSE (WHEN (SCR_MSG_IN)),
                8,
        SCR_MOVE_ABS (1) ^ SCR_MSG_IN,
                NADDR (msgin),
        SCR_JUMP,
                PADDRH (reset),
}/*-------------------------< BAD_STATUS >-----------------*/,{
        /*
        **      If command resulted in either TASK_SET FULL,
        **      CHECK CONDITION or COMMAND TERMINATED,
        **      call the C code.
        */
        SCR_INT ^ IFTRUE (DATA (SAM_STAT_TASK_SET_FULL)),
                SIR_BAD_STATUS,
        SCR_INT ^ IFTRUE (DATA (SAM_STAT_CHECK_CONDITION)),
                SIR_BAD_STATUS,
        SCR_INT ^ IFTRUE (DATA (SAM_STAT_COMMAND_TERMINATED)),
                SIR_BAD_STATUS,
        SCR_RETURN,
                0,
}/*-------------------------< START_RAM >-------------------*/,{
        /*
        **      Load the script into on-chip RAM, 
        **      and jump to start point.
        */
        SCR_COPY_F (4),
                RADDR (scratcha),
                PADDRH (start_ram0),
        /*
        **      Flush script prefetch if required
        */
        PREFETCH_FLUSH
        SCR_COPY (sizeof (struct script)),
}/*-------------------------< START_RAM0 >--------------------*/,{
                0,
                PADDR (start),
        SCR_JUMP,
                PADDR (start),
}/*-------------------------< STO_RESTART >-------------------*/,{
        /*
        **
        **      Repair start queue (e.g. next time use the next slot) 
        **      and jump to start point.
        */
        SCR_COPY (4),
                RADDR (temp),
                PADDR (startpos),
        SCR_JUMP,
                PADDR (start),
}/*-------------------------< WAIT_DMA >-------------------*/,{
        /*
        **      For HP Zalon/53c720 systems, the Zalon interface
        **      between CPU and 53c720 does prefetches, which causes
        **      problems with self modifying scripts.  The problem
        **      is overcome by calling a dummy subroutine after each
        **      modification, to force a refetch of the script on
        **      return from the subroutine.
        */
        SCR_RETURN,
                0,
}/*-------------------------< SNOOPTEST >-------------------*/,{
        /*
        **      Read the variable.
        */
        SCR_COPY (4),
                NADDR(ncr_cache),
                RADDR (scratcha),
        /*
        **      Write the variable.
        */
        SCR_COPY (4),
                RADDR (temp),
                NADDR(ncr_cache),
        /*
        **      Read back the variable.
        */
        SCR_COPY (4),
                NADDR(ncr_cache),
                RADDR (temp),
}/*-------------------------< SNOOPEND >-------------------*/,{
        /*
        **      And stop.
        */
        SCR_INT,
                99,
}/*--------------------------------------------------------*/
};

/*==========================================================
**
**
**      Fill in #define dependent parts of the script
**
**
**==========================================================
*/

void __init ncr_script_fill (struct script * scr, struct scripth * scrh)
{
        int     i;
        ncrcmd  *p;

        p = scrh->tryloop;
        for (i=0; i<MAX_START; i++) {
                *p++ =SCR_CALL;
                *p++ =PADDR (idle);
        }

        BUG_ON((u_long)p != (u_long)&scrh->tryloop + sizeof (scrh->tryloop));

#ifdef SCSI_NCR_CCB_DONE_SUPPORT

        p = scrh->done_queue;
        for (i = 0; i<MAX_DONE; i++) {
                *p++ =SCR_COPY (sizeof(struct ccb *));
                *p++ =NADDR (header.cp);
                *p++ =NADDR (ccb_done[i]);
                *p++ =SCR_CALL;
                *p++ =PADDR (done_end);
        }

        BUG_ON((u_long)p != (u_long)&scrh->done_queue+sizeof(scrh->done_queue));

#endif /* SCSI_NCR_CCB_DONE_SUPPORT */

        p = scrh->hdata_in;
        for (i=0; i<MAX_SCATTERH; i++) {
                *p++ =SCR_CALL ^ IFFALSE (WHEN (SCR_DATA_IN));
                *p++ =PADDR (dispatch);
                *p++ =SCR_MOVE_TBL ^ SCR_DATA_IN;
                *p++ =offsetof (struct dsb, data[i]);
        }

        BUG_ON((u_long)p != (u_long)&scrh->hdata_in + sizeof (scrh->hdata_in));

        p = scr->data_in;
        for (i=MAX_SCATTERH; i<MAX_SCATTERH+MAX_SCATTERL; i++) {
                *p++ =SCR_CALL ^ IFFALSE (WHEN (SCR_DATA_IN));
                *p++ =PADDR (dispatch);
                *p++ =SCR_MOVE_TBL ^ SCR_DATA_IN;
                *p++ =offsetof (struct dsb, data[i]);
        }

        BUG_ON((u_long)p != (u_long)&scr->data_in + sizeof (scr->data_in));

        p = scrh->hdata_out;
        for (i=0; i<MAX_SCATTERH; i++) {
                *p++ =SCR_CALL ^ IFFALSE (WHEN (SCR_DATA_OUT));
                *p++ =PADDR (dispatch);
                *p++ =SCR_MOVE_TBL ^ SCR_DATA_OUT;
                *p++ =offsetof (struct dsb, data[i]);
        }

        BUG_ON((u_long)p != (u_long)&scrh->hdata_out + sizeof (scrh->hdata_out));

        p = scr->data_out;
        for (i=MAX_SCATTERH; i<MAX_SCATTERH+MAX_SCATTERL; i++) {
                *p++ =SCR_CALL ^ IFFALSE (WHEN (SCR_DATA_OUT));
                *p++ =PADDR (dispatch);
                *p++ =SCR_MOVE_TBL ^ SCR_DATA_OUT;
                *p++ =offsetof (struct dsb, data[i]);
        }

        BUG_ON((u_long) p != (u_long)&scr->data_out + sizeof (scr->data_out));
}

/*==========================================================
**
**
**      Copy and rebind a script.
**
**
**==========================================================
*/

static void __init 
ncr_script_copy_and_bind (struct ncb *np, ncrcmd *src, ncrcmd *dst, int len)
{
        ncrcmd  opcode, new, old, tmp1, tmp2;
        ncrcmd  *start, *end;
        int relocs;
        int opchanged = 0;

        start = src;
        end = src + len/4;

        while (src < end) {

                opcode = *src++;
                *dst++ = cpu_to_scr(opcode);

                /*
                **      If we forget to change the length
                **      in struct script, a field will be
                **      padded with 0. This is an illegal
                **      command.
                */

                if (opcode == 0) {
                        printk (KERN_ERR "%s: ERROR0 IN SCRIPT at %d.\n",
                                ncr_name(np), (int) (src-start-1));
                        mdelay(1000);
                }

                if (DEBUG_FLAGS & DEBUG_SCRIPT)
                        printk (KERN_DEBUG "%p:  <%x>\n",
                                (src-1), (unsigned)opcode);

                /*
                **      We don't have to decode ALL commands
                */
                switch (opcode >> 28) {

                case 0xc:
                        /*
                        **      COPY has TWO arguments.
                        */
                        relocs = 2;
                        tmp1 = src[0];
#ifdef  RELOC_KVAR
                        if ((tmp1 & RELOC_MASK) == RELOC_KVAR)
                                tmp1 = 0;
#endif
                        tmp2 = src[1];
#ifdef  RELOC_KVAR
                        if ((tmp2 & RELOC_MASK) == RELOC_KVAR)
                                tmp2 = 0;
#endif
                        if ((tmp1 ^ tmp2) & 3) {
                                printk (KERN_ERR"%s: ERROR1 IN SCRIPT at %d.\n",
                                        ncr_name(np), (int) (src-start-1));
                                mdelay(1000);
                        }
                        /*
                        **      If PREFETCH feature not enabled, remove 
                        **      the NO FLUSH bit if present.
                        */
                        if ((opcode & SCR_NO_FLUSH) && !(np->features & FE_PFEN)) {
                                dst[-1] = cpu_to_scr(opcode & ~SCR_NO_FLUSH);
                                ++opchanged;
                        }
                        break;

                case 0x0:
                        /*
                        **      MOVE (absolute address)
                        */
                        relocs = 1;
                        break;

                case 0x8:
                        /*
                        **      JUMP / CALL
                        **      don't relocate if relative :-)
                        */
                        if (opcode & 0x00800000)
                                relocs = 0;
                        else
                                relocs = 1;
                        break;

                case 0x4:
                case 0x5:
                case 0x6:
                case 0x7:
                        relocs = 1;
                        break;

                default:
                        relocs = 0;
                        break;
                }

                if (relocs) {
                        while (relocs--) {
                                old = *src++;

                                switch (old & RELOC_MASK) {
                                case RELOC_REGISTER:
                                        new = (old & ~RELOC_MASK) + np->paddr;
                                        break;
                                case RELOC_LABEL:
                                        new = (old & ~RELOC_MASK) + np->p_script;
                                        break;
                                case RELOC_LABELH:
                                        new = (old & ~RELOC_MASK) + np->p_scripth;
                                        break;
                                case RELOC_SOFTC:
                                        new = (old & ~RELOC_MASK) + np->p_ncb;
                                        break;
#ifdef  RELOC_KVAR
                                case RELOC_KVAR:
                                        if (((old & ~RELOC_MASK) <
                                             SCRIPT_KVAR_FIRST) ||
                                            ((old & ~RELOC_MASK) >
                                             SCRIPT_KVAR_LAST))
                                                panic("ncr KVAR out of range");
                                        new = vtophys(script_kvars[old &
                                            ~RELOC_MASK]);
                                        break;
#endif
                                case 0:
                                        /* Don't relocate a 0 address. */
                                        if (old == 0) {
                                                new = old;
                                                break;
                                        }
                                        fallthrough;
                                default:
                                        panic("ncr_script_copy_and_bind: weird relocation %x\n", old);
                                        break;
                                }

                                *dst++ = cpu_to_scr(new);
                        }
                } else
                        *dst++ = cpu_to_scr(*src++);

        }
}

/*
**      Linux host data structure
*/

struct host_data {
     struct ncb *ncb;
};

#define PRINT_ADDR(cmd, arg...) dev_info(&cmd->device->sdev_gendev , ## arg)

static void ncr_print_msg(struct ccb *cp, char *label, u_char *msg)
{
        PRINT_ADDR(cp->cmd, "%s: ", label);

        spi_print_msg(msg);
        printk("\n");
}

/*==========================================================
**
**      NCR chip clock divisor table.
**      Divisors are multiplied by 10,000,000 in order to make 
**      calculations more simple.
**
**==========================================================
*/

#define _5M 5000000
static u_long div_10M[] =
        {2*_5M, 3*_5M, 4*_5M, 6*_5M, 8*_5M, 12*_5M, 16*_5M};


/*===============================================================
**
**      Prepare io register values used by ncr_init() according 
**      to selected and supported features.
**
**      NCR chips allow burst lengths of 2, 4, 8, 16, 32, 64, 128 
**      transfers. 32,64,128 are only supported by 875 and 895 chips.
**      We use log base 2 (burst length) as internal code, with 
**      value 0 meaning "burst disabled".
**
**===============================================================
*/

/*
 *      Burst length from burst code.
 */
#define burst_length(bc) (!(bc))? 0 : 1 << (bc)

/*
 *      Burst code from io register bits.  Burst enable is ctest0 for c720
 */
#define burst_code(dmode, ctest0) \
        (ctest0) & 0x80 ? 0 : (((dmode) & 0xc0) >> 6) + 1

/*
 *      Set initial io register bits from burst code.
 */
static inline void ncr_init_burst(struct ncb *np, u_char bc)
{
        u_char *be = &np->rv_ctest0;
        *be             &= ~0x80;
        np->rv_dmode    &= ~(0x3 << 6);
        np->rv_ctest5   &= ~0x4;

        if (!bc) {
                *be             |= 0x80;
        } else {
                --bc;
                np->rv_dmode    |= ((bc & 0x3) << 6);
                np->rv_ctest5   |= (bc & 0x4);
        }
}

static void __init ncr_prepare_setting(struct ncb *np)
{
        u_char  burst_max;
        u_long  period;
        int i;

        /*
        **      Save assumed BIOS setting
        */

        np->sv_scntl0   = INB(nc_scntl0) & 0x0a;
        np->sv_scntl3   = INB(nc_scntl3) & 0x07;
        np->sv_dmode    = INB(nc_dmode)  & 0xce;
        np->sv_dcntl    = INB(nc_dcntl)  & 0xa8;
        np->sv_ctest0   = INB(nc_ctest0) & 0x84;
        np->sv_ctest3   = INB(nc_ctest3) & 0x01;
        np->sv_ctest4   = INB(nc_ctest4) & 0x80;
        np->sv_ctest5   = INB(nc_ctest5) & 0x24;
        np->sv_gpcntl   = INB(nc_gpcntl);
        np->sv_stest2   = INB(nc_stest2) & 0x20;
        np->sv_stest4   = INB(nc_stest4);

        /*
        **      Wide ?
        */

        np->maxwide     = (np->features & FE_WIDE)? 1 : 0;

        /*
         *  Guess the frequency of the chip's clock.
         */
        if (np->features & FE_ULTRA)
                np->clock_khz = 80000;
        else
                np->clock_khz = 40000;

        /*
         *  Get the clock multiplier factor.
         */
        if      (np->features & FE_QUAD)
                np->multiplier  = 4;
        else if (np->features & FE_DBLR)
                np->multiplier  = 2;
        else
                np->multiplier  = 1;

        /*
         *  Measure SCSI clock frequency for chips 
         *  it may vary from assumed one.
         */
        if (np->features & FE_VARCLK)
                ncr_getclock(np, np->multiplier);

        /*
         * Divisor to be used for async (timer pre-scaler).
         */
        i = np->clock_divn - 1;
        while (--i >= 0) {
                if (10ul * SCSI_NCR_MIN_ASYNC * np->clock_khz > div_10M[i]) {
                        ++i;
                        break;
                }
        }
        np->rv_scntl3 = i+1;

        /*
         * Minimum synchronous period factor supported by the chip.
         * Btw, 'period' is in tenths of nanoseconds.
         */

        period = (4 * div_10M[0] + np->clock_khz - 1) / np->clock_khz;
        if      (period <= 250)         np->minsync = 10;
        else if (period <= 303)         np->minsync = 11;
        else if (period <= 500)         np->minsync = 12;
        else                            np->minsync = (period + 40 - 1) / 40;

        /*
         * Check against chip SCSI standard support (SCSI-2,ULTRA,ULTRA2).
         */

        if      (np->minsync < 25 && !(np->features & FE_ULTRA))
                np->minsync = 25;

        /*
         * Maximum synchronous period factor supported by the chip.
         */

        period = (11 * div_10M[np->clock_divn - 1]) / (4 * np->clock_khz);
        np->maxsync = period > 2540 ? 254 : period / 10;

        /*
        **      Prepare initial value of other IO registers
        */
#if defined SCSI_NCR_TRUST_BIOS_SETTING
        np->rv_scntl0   = np->sv_scntl0;
        np->rv_dmode    = np->sv_dmode;
        np->rv_dcntl    = np->sv_dcntl;
        np->rv_ctest0   = np->sv_ctest0;
        np->rv_ctest3   = np->sv_ctest3;
        np->rv_ctest4   = np->sv_ctest4;
        np->rv_ctest5   = np->sv_ctest5;
        burst_max       = burst_code(np->sv_dmode, np->sv_ctest0);
#else

        /*
        **      Select burst length (dwords)
        */
        burst_max       = driver_setup.burst_max;
        if (burst_max == 255)
                burst_max = burst_code(np->sv_dmode, np->sv_ctest0);
        if (burst_max > 7)
                burst_max = 7;
        if (burst_max > np->maxburst)
                burst_max = np->maxburst;

        /*
        **      Select all supported special features
        */
        if (np->features & FE_ERL)
                np->rv_dmode    |= ERL;         /* Enable Read Line */
        if (np->features & FE_BOF)
                np->rv_dmode    |= BOF;         /* Burst Opcode Fetch */
        if (np->features & FE_ERMP)
                np->rv_dmode    |= ERMP;        /* Enable Read Multiple */
        if (np->features & FE_PFEN)
                np->rv_dcntl    |= PFEN;        /* Prefetch Enable */
        if (np->features & FE_CLSE)
                np->rv_dcntl    |= CLSE;        /* Cache Line Size Enable */
        if (np->features & FE_WRIE)
                np->rv_ctest3   |= WRIE;        /* Write and Invalidate */
        if (np->features & FE_DFS)
                np->rv_ctest5   |= DFS;         /* Dma Fifo Size */
        if (np->features & FE_MUX)
                np->rv_ctest4   |= MUX;         /* Host bus multiplex mode */
        if (np->features & FE_EA)
                np->rv_dcntl    |= EA;          /* Enable ACK */
        if (np->features & FE_EHP)
                np->rv_ctest0   |= EHP;         /* Even host parity */

        /*
        **      Select some other
        */
        if (driver_setup.master_parity)
                np->rv_ctest4   |= MPEE;        /* Master parity checking */
        if (driver_setup.scsi_parity)
                np->rv_scntl0   |= 0x0a;        /*  full arb., ena parity, par->ATN  */

        /*
        **  Get SCSI addr of host adapter (set by bios?).
        */
        if (np->myaddr == 255) {
                np->myaddr = INB(nc_scid) & 0x07;
                if (!np->myaddr)
                        np->myaddr = SCSI_NCR_MYADDR;
        }

#endif /* SCSI_NCR_TRUST_BIOS_SETTING */

        /*
         *      Prepare initial io register bits for burst length
         */
        ncr_init_burst(np, burst_max);

        /*
        **      Set SCSI BUS mode.
        **
        **      - ULTRA2 chips (895/895A/896) report the current 
        **        BUS mode through the STEST4 IO register.
        **      - For previous generation chips (825/825A/875), 
        **        user has to tell us how to check against HVD, 
        **        since a 100% safe algorithm is not possible.
        */
        np->scsi_mode = SMODE_SE;
        if (np->features & FE_DIFF) {
                switch(driver_setup.diff_support) {
                case 4: /* Trust previous settings if present, then GPIO3 */
                        if (np->sv_scntl3) {
                                if (np->sv_stest2 & 0x20)
                                        np->scsi_mode = SMODE_HVD;
                                break;
                        }
                        fallthrough;
                case 3: /* SYMBIOS controllers report HVD through GPIO3 */
                        if (INB(nc_gpreg) & 0x08)
                                break;
                        fallthrough;
                case 2: /* Set HVD unconditionally */
                        np->scsi_mode = SMODE_HVD;
                        fallthrough;
                case 1: /* Trust previous settings for HVD */
                        if (np->sv_stest2 & 0x20)
                                np->scsi_mode = SMODE_HVD;
                        break;
                default:/* Don't care about HVD */      
                        break;
                }
        }
        if (np->scsi_mode == SMODE_HVD)
                np->rv_stest2 |= 0x20;

        /*
        **      Set LED support from SCRIPTS.
        **      Ignore this feature for boards known to use a 
        **      specific GPIO wiring and for the 895A or 896 
        **      that drive the LED directly.
        **      Also probe initial setting of GPIO0 as output.
        */
        if ((driver_setup.led_pin) &&
            !(np->features & FE_LEDC) && !(np->sv_gpcntl & 0x01))
                np->features |= FE_LED0;

        /*
        **      Set irq mode.
        */
        switch(driver_setup.irqm & 3) {
        case 2:
                np->rv_dcntl    |= IRQM;
                break;
        case 1:
                np->rv_dcntl    |= (np->sv_dcntl & IRQM);
                break;
        default:
                break;
        }

        /*
        **      Configure targets according to driver setup.
        **      Allow to override sync, wide and NOSCAN from 
        **      boot command line.
        */
        for (i = 0 ; i < MAX_TARGET ; i++) {
                struct tcb *tp = &np->target[i];

                tp->usrsync = driver_setup.default_sync;
                tp->usrwide = driver_setup.max_wide;
                tp->usrtags = MAX_TAGS;
                tp->period = 0xffff;
                if (!driver_setup.disconnection)
                        np->target[i].usrflag = UF_NODISC;
        }

        /*
        **      Announce all that stuff to user.
        */

        printk(KERN_INFO "%s: ID %d, Fast-%d%s%s\n", ncr_name(np),
                np->myaddr,
                np->minsync < 12 ? 40 : (np->minsync < 25 ? 20 : 10),
                (np->rv_scntl0 & 0xa)   ? ", Parity Checking"   : ", NO Parity",
                (np->rv_stest2 & 0x20)  ? ", Differential"      : "");

        if (bootverbose > 1) {
                printk (KERN_INFO "%s: initial SCNTL3/DMODE/DCNTL/CTEST3/4/5 = "
                        "(hex) %02x/%02x/%02x/%02x/%02x/%02x\n",
                        ncr_name(np), np->sv_scntl3, np->sv_dmode, np->sv_dcntl,
                        np->sv_ctest3, np->sv_ctest4, np->sv_ctest5);

                printk (KERN_INFO "%s: final   SCNTL3/DMODE/DCNTL/CTEST3/4/5 = "
                        "(hex) %02x/%02x/%02x/%02x/%02x/%02x\n",
                        ncr_name(np), np->rv_scntl3, np->rv_dmode, np->rv_dcntl,
                        np->rv_ctest3, np->rv_ctest4, np->rv_ctest5);
        }

        if (bootverbose && np->paddr2)
                printk (KERN_INFO "%s: on-chip RAM at 0x%lx\n",
                        ncr_name(np), np->paddr2);
}

/*==========================================================
**
**
**      Done SCSI commands list management.
**
**      We donnot enter the scsi_done() callback immediately 
**      after a command has been seen as completed but we 
**      insert it into a list which is flushed outside any kind 
**      of driver critical section.
**      This allows to do minimal stuff under interrupt and 
**      inside critical sections and to also avoid locking up 
**      on recursive calls to driver entry points under SMP.
**      In fact, the only kernel point which is entered by the 
**      driver with a driver lock set is kmalloc(GFP_ATOMIC) 
**      that shall not reenter the driver under any circumstances,
**      AFAIK.
**
**==========================================================
*/
static inline void ncr_queue_done_cmd(struct ncb *np, struct scsi_cmnd *cmd)
{
        unmap_scsi_data(np, cmd);
        cmd->host_scribble = (char *) np->done_list;
        np->done_list = cmd;
}

static inline void ncr_flush_done_cmds(struct scsi_cmnd *lcmd)
{
        struct scsi_cmnd *cmd;

        while (lcmd) {
                cmd = lcmd;
                lcmd = (struct scsi_cmnd *) cmd->host_scribble;
                scsi_done(cmd);
        }
}

/*==========================================================
**
**
**      Prepare the next negotiation message if needed.
**
**      Fill in the part of message buffer that contains the 
**      negotiation and the nego_status field of the CCB.
**      Returns the size of the message in bytes.
**
**
**==========================================================
*/


static int ncr_prepare_nego(struct ncb *np, struct ccb *cp, u_char *msgptr)
{
        struct tcb *tp = &np->target[cp->target];
        int msglen = 0;
        int nego = 0;
        struct scsi_target *starget = tp->starget;

        /* negotiate wide transfers ?  */
        if (!tp->widedone) {
                if (spi_support_wide(starget)) {
                        nego = NS_WIDE;
                } else
                        tp->widedone=1;
        }

        /* negotiate synchronous transfers?  */
        if (!nego && !tp->period) {
                if (spi_support_sync(starget)) {
                        nego = NS_SYNC;
                } else {
                        tp->period  =0xffff;
                        dev_info(&starget->dev, "target did not report SYNC.\n");
                }
        }

        switch (nego) {
        case NS_SYNC:
                msglen += spi_populate_sync_msg(msgptr + msglen,
                                tp->maxoffs ? tp->minsync : 0, tp->maxoffs);
                break;
        case NS_WIDE:
                msglen += spi_populate_width_msg(msgptr + msglen, tp->usrwide);
                break;
        }

        cp->nego_status = nego;

        if (nego) {
                tp->nego_cp = cp;
                if (DEBUG_FLAGS & DEBUG_NEGO) {
                        ncr_print_msg(cp, nego == NS_WIDE ?
                                          "wide msgout":"sync_msgout", msgptr);
                }
        }

        return msglen;
}



/*==========================================================
**
**
**      Start execution of a SCSI command.
**      This is called from the generic SCSI driver.
**
**
**==========================================================
*/
static int ncr_queue_command (struct ncb *np, struct scsi_cmnd *cmd)
{
        struct scsi_device *sdev = cmd->device;
        struct tcb *tp = &np->target[sdev->id];
        struct lcb *lp = tp->lp[sdev->lun];
        struct ccb *cp;

        int     segments;
        u_char  idmsg, *msgptr;
        u32     msglen;
        int     direction;
        u32     lastp, goalp;

        /*---------------------------------------------
        **
        **      Some shortcuts ...
        **
        **---------------------------------------------
        */
        if ((sdev->id == np->myaddr       ) ||
                (sdev->id >= MAX_TARGET) ||
                (sdev->lun    >= MAX_LUN   )) {
                return(DID_BAD_TARGET);
        }

        /*---------------------------------------------
        **
        **      Complete the 1st TEST UNIT READY command
        **      with error condition if the device is 
        **      flagged NOSCAN, in order to speed up 
        **      the boot.
        **
        **---------------------------------------------
        */
        if ((cmd->cmnd[0] == 0 || cmd->cmnd[0] == 0x12) && 
            (tp->usrflag & UF_NOSCAN)) {
                tp->usrflag &= ~UF_NOSCAN;
                return DID_BAD_TARGET;
        }

        if (DEBUG_FLAGS & DEBUG_TINY) {
                PRINT_ADDR(cmd, "CMD=%x ", cmd->cmnd[0]);
        }

        /*---------------------------------------------------
        **
        **      Assign a ccb / bind cmd.
        **      If resetting, shorten settle_time if necessary
        **      in order to avoid spurious timeouts.
        **      If resetting or no free ccb,
        **      insert cmd into the waiting list.
        **
        **----------------------------------------------------
        */
        if (np->settle_time && scsi_cmd_to_rq(cmd)->timeout >= HZ) {
                u_long tlimit = jiffies + scsi_cmd_to_rq(cmd)->timeout - HZ;
                if (time_after(np->settle_time, tlimit))
                        np->settle_time = tlimit;
        }

        if (np->settle_time || !(cp=ncr_get_ccb (np, cmd))) {
                insert_into_waiting_list(np, cmd);
                return(DID_OK);
        }
        cp->cmd = cmd;

        /*----------------------------------------------------
        **
        **      Build the identify / tag / sdtr message
        **
        **----------------------------------------------------
        */

        idmsg = IDENTIFY(0, sdev->lun);

        if (cp ->tag != NO_TAG ||
                (cp != np->ccb && np->disc && !(tp->usrflag & UF_NODISC)))
                idmsg |= 0x40;

        msgptr = cp->scsi_smsg;
        msglen = 0;
        msgptr[msglen++] = idmsg;

        if (cp->tag != NO_TAG) {
                char order = np->order;

                /*
                **      Force ordered tag if necessary to avoid timeouts 
                **      and to preserve interactivity.
                */
                if (lp && time_after(jiffies, lp->tags_stime)) {
                        if (lp->tags_smap) {
                                order = ORDERED_QUEUE_TAG;
                                if ((DEBUG_FLAGS & DEBUG_TAGS)||bootverbose>2){ 
                                        PRINT_ADDR(cmd,
                                                "ordered tag forced.\n");
                                }
                        }
                        lp->tags_stime = jiffies + 3*HZ;
                        lp->tags_smap = lp->tags_umap;
                }

                if (order == 0) {
                        /*
                        **      Ordered write ops, unordered read ops.
                        */
                        switch (cmd->cmnd[0]) {
                        case 0x08:  /* READ_SMALL (6) */
                        case 0x28:  /* READ_BIG  (10) */
                        case 0xa8:  /* READ_HUGE (12) */
                                order = SIMPLE_QUEUE_TAG;
                                break;
                        default:
                                order = ORDERED_QUEUE_TAG;
                        }
                }
                msgptr[msglen++] = order;
                /*
                **      Actual tags are numbered 1,3,5,..2*MAXTAGS+1,
                **      since we may have to deal with devices that have 
                **      problems with #TAG 0 or too great #TAG numbers.
                */
                msgptr[msglen++] = (cp->tag << 1) + 1;
        }

        /*----------------------------------------------------
        **
        **      Build the data descriptors
        **
        **----------------------------------------------------
        */

        direction = cmd->sc_data_direction;
        if (direction != DMA_NONE) {
                segments = ncr_scatter(np, cp, cp->cmd);
                if (segments < 0) {
                        ncr_free_ccb(np, cp);
                        return(DID_ERROR);
                }
        }
        else {
                cp->data_len = 0;
                segments = 0;
        }

        /*---------------------------------------------------
        **
        **      negotiation required?
        **
        **      (nego_status is filled by ncr_prepare_nego())
        **
        **---------------------------------------------------
        */

        cp->nego_status = 0;

        if ((!tp->widedone || !tp->period) && !tp->nego_cp && lp) {
                msglen += ncr_prepare_nego (np, cp, msgptr + msglen);
        }

        /*----------------------------------------------------
        **
        **      Determine xfer direction.
        **
        **----------------------------------------------------
        */
        if (!cp->data_len)
                direction = DMA_NONE;

        /*
        **      If data direction is BIDIRECTIONAL, speculate FROM_DEVICE
        **      but prepare alternate pointers for TO_DEVICE in case 
        **      of our speculation will be just wrong.
        **      SCRIPTS will swap values if needed.
        */
        switch(direction) {
        case DMA_BIDIRECTIONAL:
        case DMA_TO_DEVICE:
                goalp = NCB_SCRIPT_PHYS (np, data_out2) + 8;
                if (segments <= MAX_SCATTERL)
                        lastp = goalp - 8 - (segments * 16);
                else {
                        lastp = NCB_SCRIPTH_PHYS (np, hdata_out2);
                        lastp -= (segments - MAX_SCATTERL) * 16;
                }
                if (direction != DMA_BIDIRECTIONAL)
                        break;
                cp->phys.header.wgoalp  = cpu_to_scr(goalp);
                cp->phys.header.wlastp  = cpu_to_scr(lastp);
                fallthrough;
        case DMA_FROM_DEVICE:
                goalp = NCB_SCRIPT_PHYS (np, data_in2) + 8;
                if (segments <= MAX_SCATTERL)
                        lastp = goalp - 8 - (segments * 16);
                else {
                        lastp = NCB_SCRIPTH_PHYS (np, hdata_in2);
                        lastp -= (segments - MAX_SCATTERL) * 16;
                }
                break;
        default:
        case DMA_NONE:
                lastp = goalp = NCB_SCRIPT_PHYS (np, no_data);
                break;
        }

        /*
        **      Set all pointers values needed by SCRIPTS.
        **      If direction is unknown, start at data_io.
        */
        cp->phys.header.lastp = cpu_to_scr(lastp);
        cp->phys.header.goalp = cpu_to_scr(goalp);

        if (direction == DMA_BIDIRECTIONAL)
                cp->phys.header.savep = 
                        cpu_to_scr(NCB_SCRIPTH_PHYS (np, data_io));
        else
                cp->phys.header.savep= cpu_to_scr(lastp);

        /*
        **      Save the initial data pointer in order to be able 
        **      to redo the command.
        */
        cp->startp = cp->phys.header.savep;

        /*----------------------------------------------------
        **
        **      fill in ccb
        **
        **----------------------------------------------------
        **
        **
        **      physical -> virtual backlink
        **      Generic SCSI command
        */

        /*
        **      Startqueue
        */
        cp->start.schedule.l_paddr   = cpu_to_scr(NCB_SCRIPT_PHYS (np, select));
        cp->restart.schedule.l_paddr = cpu_to_scr(NCB_SCRIPT_PHYS (np, resel_dsa));
        /*
        **      select
        */
        cp->phys.select.sel_id          = sdev_id(sdev);
        cp->phys.select.sel_scntl3      = tp->wval;
        cp->phys.select.sel_sxfer       = tp->sval;
        /*
        **      message
        */
        cp->phys.smsg.addr              = cpu_to_scr(CCB_PHYS (cp, scsi_smsg));
        cp->phys.smsg.size              = cpu_to_scr(msglen);

        /*
        **      command
        */
        memcpy(cp->cdb_buf, cmd->cmnd, min_t(int, cmd->cmd_len, sizeof(cp->cdb_buf)));
        cp->phys.cmd.addr               = cpu_to_scr(CCB_PHYS (cp, cdb_buf[0]));
        cp->phys.cmd.size               = cpu_to_scr(cmd->cmd_len);

        /*
        **      status
        */
        cp->actualquirks                = 0;
        cp->host_status                 = cp->nego_status ? HS_NEGOTIATE : HS_BUSY;
        cp->scsi_status                 = SAM_STAT_ILLEGAL;
        cp->parity_status               = 0;

        cp->xerr_status                 = XE_OK;

        /*----------------------------------------------------
        **
        **      Critical region: start this job.
        **
        **----------------------------------------------------
        */

        /* activate this job.  */
        cp->magic               = CCB_MAGIC;

        /*
        **      insert next CCBs into start queue.
        **      2 max at a time is enough to flush the CCB wait queue.
        */
        cp->auto_sense = 0;
        if (lp)
                ncr_start_next_ccb(np, lp, 2);
        else
                ncr_put_start_queue(np, cp);

        /* Command is successfully queued.  */

        return DID_OK;
}


/*==========================================================
**
**
**      Insert a CCB into the start queue and wake up the 
**      SCRIPTS processor.
**
**
**==========================================================
*/

static void ncr_start_next_ccb(struct ncb *np, struct lcb *lp, int maxn)
{
        struct list_head *qp;
        struct ccb *cp;

        if (lp->held_ccb)
                return;

        while (maxn-- && lp->queuedccbs < lp->queuedepth) {
                qp = ncr_list_pop(&lp->wait_ccbq);
                if (!qp)
                        break;
                ++lp->queuedccbs;
                cp = list_entry(qp, struct ccb, link_ccbq);
                list_add_tail(qp, &lp->busy_ccbq);
                lp->jump_ccb[cp->tag == NO_TAG ? 0 : cp->tag] =
                        cpu_to_scr(CCB_PHYS (cp, restart));
                ncr_put_start_queue(np, cp);
        }
}

static void ncr_put_start_queue(struct ncb *np, struct ccb *cp)
{
        u16     qidx;

        /*
        **      insert into start queue.
        */
        if (!np->squeueput) np->squeueput = 1;
        qidx = np->squeueput + 2;
        if (qidx >= MAX_START + MAX_START) qidx = 1;

        np->scripth->tryloop [qidx] = cpu_to_scr(NCB_SCRIPT_PHYS (np, idle));
        MEMORY_BARRIER();
        np->scripth->tryloop [np->squeueput] = cpu_to_scr(CCB_PHYS (cp, start));

        np->squeueput = qidx;
        ++np->queuedccbs;
        cp->queued = 1;

        if (DEBUG_FLAGS & DEBUG_QUEUE)
                printk ("%s: queuepos=%d.\n", ncr_name (np), np->squeueput);

        /*
        **      Script processor may be waiting for reselect.
        **      Wake it up.
        */
        MEMORY_BARRIER();
        OUTB (nc_istat, SIGP);
}


static int ncr_reset_scsi_bus(struct ncb *np, int enab_int, int settle_delay)
{
        u32 term;
        int retv = 0;

        np->settle_time = jiffies + settle_delay * HZ;

        if (bootverbose > 1)
                printk("%s: resetting, "
                        "command processing suspended for %d seconds\n",
                        ncr_name(np), settle_delay);

        ncr_chip_reset(np, 100);
        udelay(2000);   /* The 895 needs time for the bus mode to settle */
        if (enab_int)
                OUTW (nc_sien, RST);
        /*
        **      Enable Tolerant, reset IRQD if present and 
        **      properly set IRQ mode, prior to resetting the bus.
        */
        OUTB (nc_stest3, TE);
        OUTB (nc_scntl1, CRST);
        udelay(200);

        if (!driver_setup.bus_check)
                goto out;
        /*
        **      Check for no terminators or SCSI bus shorts to ground.
        **      Read SCSI data bus, data parity bits and control signals.
        **      We are expecting RESET to be TRUE and other signals to be 
        **      FALSE.
        */

        term =  INB(nc_sstat0);
        term =  ((term & 2) << 7) + ((term & 1) << 17); /* rst sdp0 */
        term |= ((INB(nc_sstat2) & 0x01) << 26) |       /* sdp1     */
                ((INW(nc_sbdl) & 0xff)   << 9)  |       /* d7-0     */
                ((INW(nc_sbdl) & 0xff00) << 10) |       /* d15-8    */
                INB(nc_sbcl);   /* req ack bsy sel atn msg cd io    */

        if (!(np->features & FE_WIDE))
                term &= 0x3ffff;

        if (term != (2<<7)) {
                printk("%s: suspicious SCSI data while resetting the BUS.\n",
                        ncr_name(np));
                printk("%s: %sdp0,d7-0,rst,req,ack,bsy,sel,atn,msg,c/d,i/o = "
                        "0x%lx, expecting 0x%lx\n",
                        ncr_name(np),
                        (np->features & FE_WIDE) ? "dp1,d15-8," : "",
                        (u_long)term, (u_long)(2<<7));
                if (driver_setup.bus_check == 1)
                        retv = 1;
        }
out:
        OUTB (nc_scntl1, 0);
        return retv;
}

/*
 * Start reset process.
 * If reset in progress do nothing.
 * The interrupt handler will reinitialize the chip.
 * The timeout handler will wait for settle_time before 
 * clearing it and so resuming command processing.
 */
static void ncr_start_reset(struct ncb *np)
{
        if (!np->settle_time) {
                ncr_reset_scsi_bus(np, 1, driver_setup.settle_delay);
        }
}
 
/*==========================================================
**
**
**      Reset the SCSI BUS.
**      This is called from the generic SCSI driver.
**
**
**==========================================================
*/
static int ncr_reset_bus (struct ncb *np)
{
/*
 * Return immediately if reset is in progress.
 */
        if (np->settle_time) {
                return FAILED;
        }
/*
 * Start the reset process.
 * The script processor is then assumed to be stopped.
 * Commands will now be queued in the waiting list until a settle 
 * delay of 2 seconds will be completed.
 */
        ncr_start_reset(np);
/*
 * Wake-up all awaiting commands with DID_RESET.
 */
        reset_waiting_list(np);
/*
 * Wake-up all pending commands with HS_RESET -> DID_RESET.
 */
        ncr_wakeup(np, HS_RESET);

        return SUCCESS;
}

static void ncr_detach(struct ncb *np)
{
        struct ccb *cp;
        struct tcb *tp;
        struct lcb *lp;
        int target, lun;
        int i;
        char inst_name[16];

        /* Local copy so we don't access np after freeing it! */
        strscpy(inst_name, ncr_name(np), sizeof(inst_name));

        printk("%s: releasing host resources\n", ncr_name(np));

/*
**      Stop the ncr_timeout process
**      Set release_stage to 1 and wait that ncr_timeout() set it to 2.
*/

#ifdef DEBUG_NCR53C8XX
        printk("%s: stopping the timer\n", ncr_name(np));
#endif
        np->release_stage = 1;
        for (i = 50 ; i && np->release_stage != 2 ; i--)
                mdelay(100);
        if (np->release_stage != 2)
                printk("%s: the timer seems to be already stopped\n", ncr_name(np));
        else np->release_stage = 2;

/*
**      Disable chip interrupts
*/

#ifdef DEBUG_NCR53C8XX
        printk("%s: disabling chip interrupts\n", ncr_name(np));
#endif
        OUTW (nc_sien , 0);
        OUTB (nc_dien , 0);

        /*
        **      Reset NCR chip
        **      Restore bios setting for automatic clock detection.
        */

        printk("%s: resetting chip\n", ncr_name(np));
        ncr_chip_reset(np, 100);

        OUTB(nc_dmode,  np->sv_dmode);
        OUTB(nc_dcntl,  np->sv_dcntl);
        OUTB(nc_ctest0, np->sv_ctest0);
        OUTB(nc_ctest3, np->sv_ctest3);
        OUTB(nc_ctest4, np->sv_ctest4);
        OUTB(nc_ctest5, np->sv_ctest5);
        OUTB(nc_gpcntl, np->sv_gpcntl);
        OUTB(nc_stest2, np->sv_stest2);

        ncr_selectclock(np, np->sv_scntl3);

        /*
        **      Free allocated ccb(s)
        */

        while ((cp=np->ccb->link_ccb) != NULL) {
                np->ccb->link_ccb = cp->link_ccb;
                if (cp->host_status) {
                printk("%s: shall free an active ccb (host_status=%d)\n",
                        ncr_name(np), cp->host_status);
                }
#ifdef DEBUG_NCR53C8XX
        printk("%s: freeing ccb (%lx)\n", ncr_name(np), (u_long) cp);
#endif
                m_free_dma(cp, sizeof(*cp), "CCB");
        }

        /* Free allocated tp(s) */

        for (target = 0; target < MAX_TARGET ; target++) {
                tp=&np->target[target];
                for (lun = 0 ; lun < MAX_LUN ; lun++) {
                        lp = tp->lp[lun];
                        if (lp) {
#ifdef DEBUG_NCR53C8XX
        printk("%s: freeing lp (%lx)\n", ncr_name(np), (u_long) lp);
#endif
                                if (lp->jump_ccb != &lp->jump_ccb_0)
                                        m_free_dma(lp->jump_ccb,256,"JUMP_CCB");
                                m_free_dma(lp, sizeof(*lp), "LCB");
                        }
                }
        }

        if (np->scripth0)
                m_free_dma(np->scripth0, sizeof(struct scripth), "SCRIPTH");
        if (np->script0)
                m_free_dma(np->script0, sizeof(struct script), "SCRIPT");
        if (np->ccb)
                m_free_dma(np->ccb, sizeof(struct ccb), "CCB");
        m_free_dma(np, sizeof(struct ncb), "NCB");

        printk("%s: host resources successfully released\n", inst_name);
}

/*==========================================================
**
**
**      Complete execution of a SCSI command.
**      Signal completion to the generic SCSI driver.
**
**
**==========================================================
*/

void ncr_complete (struct ncb *np, struct ccb *cp)
{
        struct scsi_cmnd *cmd;
        struct tcb *tp;
        struct lcb *lp;

        /*
        **      Sanity check
        */

        if (!cp || cp->magic != CCB_MAGIC || !cp->cmd)
                return;

        /*
        **      Print minimal debug information.
        */

        if (DEBUG_FLAGS & DEBUG_TINY)
                printk ("CCB=%lx STAT=%x/%x\n", (unsigned long)cp,
                        cp->host_status,cp->scsi_status);

        /*
        **      Get command, target and lun pointers.
        */

        cmd = cp->cmd;
        cp->cmd = NULL;
        tp = &np->target[cmd->device->id];
        lp = tp->lp[cmd->device->lun];

        /*
        **      We donnot queue more than 1 ccb per target 
        **      with negotiation at any time. If this ccb was 
        **      used for negotiation, clear this info in the tcb.
        */

        if (cp == tp->nego_cp)
                tp->nego_cp = NULL;

        /*
        **      If auto-sense performed, change scsi status.
        */
        if (cp->auto_sense) {
                cp->scsi_status = cp->auto_sense;
        }

        /*
        **      If we were recovering from queue full or performing 
        **      auto-sense, requeue skipped CCBs to the wait queue.
        */

        if (lp && lp->held_ccb) {
                if (cp == lp->held_ccb) {
                        list_splice_init(&lp->skip_ccbq, &lp->wait_ccbq);
                        lp->held_ccb = NULL;
                }
        }

        /*
        **      Check for parity errors.
        */

        if (cp->parity_status > 1) {
                PRINT_ADDR(cmd, "%d parity error(s).\n",cp->parity_status);
        }

        /*
        **      Check for extended errors.
        */

        if (cp->xerr_status != XE_OK) {
                switch (cp->xerr_status) {
                case XE_EXTRA_DATA:
                        PRINT_ADDR(cmd, "extraneous data discarded.\n");
                        break;
                case XE_BAD_PHASE:
                        PRINT_ADDR(cmd, "invalid scsi phase (4/5).\n");
                        break;
                default:
                        PRINT_ADDR(cmd, "extended error %d.\n",
                                        cp->xerr_status);
                        break;
                }
                if (cp->host_status==HS_COMPLETE)
                        cp->host_status = HS_FAIL;
        }

        /*
        **      Print out any error for debugging purpose.
        */
        if (DEBUG_FLAGS & (DEBUG_RESULT|DEBUG_TINY)) {
                if (cp->host_status != HS_COMPLETE ||
                    cp->scsi_status != SAM_STAT_GOOD) {
                        PRINT_ADDR(cmd, "ERROR: cmd=%x host_status=%x "
                                        "scsi_status=%x\n", cmd->cmnd[0],
                                        cp->host_status, cp->scsi_status);
                }
        }

        /*
        **      Check the status.
        */
        cmd->result = 0;
        if (   (cp->host_status == HS_COMPLETE)
                && (cp->scsi_status == SAM_STAT_GOOD ||
                    cp->scsi_status == SAM_STAT_CONDITION_MET)) {
                /*
                 *      All went well (GOOD status).
                 *      CONDITION MET status is returned on
                 *      `Pre-Fetch' or `Search data' success.
                 */
                set_status_byte(cmd, cp->scsi_status);

                /*
                **      @RESID@
                **      Could dig out the correct value for resid,
                **      but it would be quite complicated.
                */
                /* if (cp->phys.header.lastp != cp->phys.header.goalp) */

                /*
                **      Allocate the lcb if not yet.
                */
                if (!lp)
                        ncr_alloc_lcb (np, cmd->device->id, cmd->device->lun);

                tp->bytes     += cp->data_len;
                tp->transfers ++;

                /*
                **      If tags was reduced due to queue full,
                **      increase tags if 1000 good status received.
                */
                if (lp && lp->usetags && lp->numtags < lp->maxtags) {
                        ++lp->num_good;
                        if (lp->num_good >= 1000) {
                                lp->num_good = 0;
                                ++lp->numtags;
                                ncr_setup_tags (np, cmd->device);
                        }
                }
        } else if ((cp->host_status == HS_COMPLETE)
                && (cp->scsi_status == SAM_STAT_CHECK_CONDITION)) {
                /*
                **   Check condition code
                */
                set_status_byte(cmd, SAM_STAT_CHECK_CONDITION);

                /*
                **      Copy back sense data to caller's buffer.
                */
                memcpy(cmd->sense_buffer, cp->sense_buf,
                       min_t(size_t, SCSI_SENSE_BUFFERSIZE,
                             sizeof(cp->sense_buf)));

                if (DEBUG_FLAGS & (DEBUG_RESULT|DEBUG_TINY)) {
                        u_char *p = cmd->sense_buffer;
                        int i;
                        PRINT_ADDR(cmd, "sense data:");
                        for (i=0; i<14; i++) printk (" %x", *p++);
                        printk (".\n");
                }
        } else if ((cp->host_status == HS_COMPLETE)
                && (cp->scsi_status == SAM_STAT_RESERVATION_CONFLICT)) {
                /*
                **   Reservation Conflict condition code
                */
                set_status_byte(cmd, SAM_STAT_RESERVATION_CONFLICT);

        } else if ((cp->host_status == HS_COMPLETE)
                && (cp->scsi_status == SAM_STAT_BUSY ||
                    cp->scsi_status == SAM_STAT_TASK_SET_FULL)) {

                /*
                **   Target is busy.
                */
                set_status_byte(cmd, cp->scsi_status);

        } else if ((cp->host_status == HS_SEL_TIMEOUT)
                || (cp->host_status == HS_TIMEOUT)) {

                /*
                **   No response
                */
                set_status_byte(cmd, cp->scsi_status);
                set_host_byte(cmd, DID_TIME_OUT);

        } else if (cp->host_status == HS_RESET) {

                /*
                **   SCSI bus reset
                */
                set_status_byte(cmd, cp->scsi_status);
                set_host_byte(cmd, DID_RESET);

        } else if (cp->host_status == HS_ABORTED) {

                /*
                **   Transfer aborted
                */
                set_status_byte(cmd, cp->scsi_status);
                set_host_byte(cmd, DID_ABORT);

        } else {

                /*
                **  Other protocol messes
                */
                PRINT_ADDR(cmd, "COMMAND FAILED (%x %x) @%p.\n",
                        cp->host_status, cp->scsi_status, cp);

                set_status_byte(cmd, cp->scsi_status);
                set_host_byte(cmd, DID_ERROR);
        }

        /*
        **      trace output
        */

        if (tp->usrflag & UF_TRACE) {
                u_char * p;
                int i;
                PRINT_ADDR(cmd, " CMD:");
                p = (u_char*) &cmd->cmnd[0];
                for (i=0; i<cmd->cmd_len; i++) printk (" %x", *p++);

                if (cp->host_status==HS_COMPLETE) {
                        switch (cp->scsi_status) {
                        case SAM_STAT_GOOD:
                                printk ("  GOOD");
                                break;
                        case SAM_STAT_CHECK_CONDITION:
                                printk ("  SENSE:");
                                p = (u_char*) &cmd->sense_buffer;
                                for (i=0; i<14; i++)
                                        printk (" %x", *p++);
                                break;
                        default:
                                printk ("  STAT: %x\n", cp->scsi_status);
                                break;
                        }
                } else printk ("  HOSTERROR: %x", cp->host_status);
                printk ("\n");
        }

        /*
        **      Free this ccb
        */
        ncr_free_ccb (np, cp);

        /*
        **      requeue awaiting scsi commands for this lun.
        */
        if (lp && lp->queuedccbs < lp->queuedepth &&
            !list_empty(&lp->wait_ccbq))
                ncr_start_next_ccb(np, lp, 2);

        /*
        **      requeue awaiting scsi commands for this controller.
        */
        if (np->waiting_list)
                requeue_waiting_list(np);

        /*
        **      signal completion to generic driver.
        */
        ncr_queue_done_cmd(np, cmd);
}

/*==========================================================
**
**
**      Signal all (or one) control block done.
**
**
**==========================================================
*/

/*
**      This CCB has been skipped by the NCR.
**      Queue it in the corresponding unit queue.
*/
static void ncr_ccb_skipped(struct ncb *np, struct ccb *cp)
{
        struct tcb *tp = &np->target[cp->target];
        struct lcb *lp = tp->lp[cp->lun];

        if (lp && cp != np->ccb) {
                cp->host_status &= ~HS_SKIPMASK;
                cp->start.schedule.l_paddr = 
                        cpu_to_scr(NCB_SCRIPT_PHYS (np, select));
                list_move_tail(&cp->link_ccbq, &lp->skip_ccbq);
                if (cp->queued) {
                        --lp->queuedccbs;
                }
        }
        if (cp->queued) {
                --np->queuedccbs;
                cp->queued = 0;
        }
}

/*
**      The NCR has completed CCBs.
**      Look at the DONE QUEUE if enabled, otherwise scan all CCBs
*/
void ncr_wakeup_done (struct ncb *np)
{
        struct ccb *cp;
#ifdef SCSI_NCR_CCB_DONE_SUPPORT
        int i, j;

        i = np->ccb_done_ic;
        while (1) {
                j = i+1;
                if (j >= MAX_DONE)
                        j = 0;

                cp = np->ccb_done[j];
                if (!CCB_DONE_VALID(cp))
                        break;

                np->ccb_done[j] = (struct ccb *)CCB_DONE_EMPTY;
                np->scripth->done_queue[5*j + 4] =
                                cpu_to_scr(NCB_SCRIPT_PHYS (np, done_plug));
                MEMORY_BARRIER();
                np->scripth->done_queue[5*i + 4] =
                                cpu_to_scr(NCB_SCRIPT_PHYS (np, done_end));

                if (cp->host_status & HS_DONEMASK)
                        ncr_complete (np, cp);
                else if (cp->host_status & HS_SKIPMASK)
                        ncr_ccb_skipped (np, cp);

                i = j;
        }
        np->ccb_done_ic = i;
#else
        cp = np->ccb;
        while (cp) {
                if (cp->host_status & HS_DONEMASK)
                        ncr_complete (np, cp);
                else if (cp->host_status & HS_SKIPMASK)
                        ncr_ccb_skipped (np, cp);
                cp = cp->link_ccb;
        }
#endif
}

/*
**      Complete all active CCBs.
*/
void ncr_wakeup (struct ncb *np, u_long code)
{
        struct ccb *cp = np->ccb;

        while (cp) {
                if (cp->host_status != HS_IDLE) {
                        cp->host_status = code;
                        ncr_complete (np, cp);
                }
                cp = cp->link_ccb;
        }
}

/*
** Reset ncr chip.
*/

/* Some initialisation must be done immediately following reset, for 53c720,
 * at least.  EA (dcntl bit 5) isn't set here as it is set once only in
 * the _detect function.
 */
static void ncr_chip_reset(struct ncb *np, int delay)
{
        OUTB (nc_istat,  SRST);
        udelay(delay);
        OUTB (nc_istat,  0   );

        if (np->features & FE_EHP)
                OUTB (nc_ctest0, EHP);
        if (np->features & FE_MUX)
                OUTB (nc_ctest4, MUX);
}


/*==========================================================
**
**
**      Start NCR chip.
**
**
**==========================================================
*/

void ncr_init (struct ncb *np, int reset, char * msg, u_long code)
{
        int     i;

        /*
        **      Reset chip if asked, otherwise just clear fifos.
        */

        if (reset) {
                OUTB (nc_istat,  SRST);
                udelay(100);
        }
        else {
                OUTB (nc_stest3, TE|CSF);
                OUTONB (nc_ctest3, CLF);
        }
 
        /*
        **      Message.
        */

        if (msg) printk (KERN_INFO "%s: restart (%s).\n", ncr_name (np), msg);

        /*
        **      Clear Start Queue
        */
        np->queuedepth = MAX_START - 1; /* 1 entry needed as end marker */
        for (i = 1; i < MAX_START + MAX_START; i += 2)
                np->scripth0->tryloop[i] =
                                cpu_to_scr(NCB_SCRIPT_PHYS (np, idle));

        /*
        **      Start at first entry.
        */
        np->squeueput = 0;
        np->script0->startpos[0] = cpu_to_scr(NCB_SCRIPTH_PHYS (np, tryloop));

#ifdef SCSI_NCR_CCB_DONE_SUPPORT
        /*
        **      Clear Done Queue
        */
        for (i = 0; i < MAX_DONE; i++) {
                np->ccb_done[i] = (struct ccb *)CCB_DONE_EMPTY;
                np->scripth0->done_queue[5*i + 4] =
                        cpu_to_scr(NCB_SCRIPT_PHYS (np, done_end));
        }
#endif

        /*
        **      Start at first entry.
        */
        np->script0->done_pos[0] = cpu_to_scr(NCB_SCRIPTH_PHYS (np,done_queue));
        np->ccb_done_ic = MAX_DONE-1;
        np->scripth0->done_queue[5*(MAX_DONE-1) + 4] =
                        cpu_to_scr(NCB_SCRIPT_PHYS (np, done_plug));

        /*
        **      Wakeup all pending jobs.
        */
        ncr_wakeup (np, code);

        /*
        **      Init chip.
        */

        /*
        ** Remove reset; big delay because the 895 needs time for the
        ** bus mode to settle
        */
        ncr_chip_reset(np, 2000);

        OUTB (nc_scntl0, np->rv_scntl0 | 0xc0);
                                        /*  full arb., ena parity, par->ATN  */
        OUTB (nc_scntl1, 0x00);         /*  odd parity, and remove CRST!! */

        ncr_selectclock(np, np->rv_scntl3);     /* Select SCSI clock */

        OUTB (nc_scid  , RRE|np->myaddr);       /* Adapter SCSI address */
        OUTW (nc_respid, 1ul<<np->myaddr);      /* Id to respond to */
        OUTB (nc_istat , SIGP   );              /*  Signal Process */
        OUTB (nc_dmode , np->rv_dmode);         /* Burst length, dma mode */
        OUTB (nc_ctest5, np->rv_ctest5);        /* Large fifo + large burst */

        OUTB (nc_dcntl , NOCOM|np->rv_dcntl);   /* Protect SFBR */
        OUTB (nc_ctest0, np->rv_ctest0);        /* 720: CDIS and EHP */
        OUTB (nc_ctest3, np->rv_ctest3);        /* Write and invalidate */
        OUTB (nc_ctest4, np->rv_ctest4);        /* Master parity checking */

        OUTB (nc_stest2, EXT|np->rv_stest2);    /* Extended Sreq/Sack filtering */
        OUTB (nc_stest3, TE);                   /* TolerANT enable */
        OUTB (nc_stime0, 0x0c   );              /* HTH disabled  STO 0.25 sec */

        /*
        **      Disable disconnects.
        */

        np->disc = 0;

        /*
        **    Enable GPIO0 pin for writing if LED support.
        */

        if (np->features & FE_LED0) {
                OUTOFFB (nc_gpcntl, 0x01);
        }

        /*
        **      enable ints
        */

        OUTW (nc_sien , STO|HTH|MA|SGE|UDC|RST|PAR);
        OUTB (nc_dien , MDPE|BF|ABRT|SSI|SIR|IID);

        /*
        **      Fill in target structure.
        **      Reinitialize usrsync.
        **      Reinitialize usrwide.
        **      Prepare sync negotiation according to actual SCSI bus mode.
        */

        for (i=0;i<MAX_TARGET;i++) {
                struct tcb *tp = &np->target[i];

                tp->sval    = 0;
                tp->wval    = np->rv_scntl3;

                if (tp->usrsync != 255) {
                        if (tp->usrsync <= np->maxsync) {
                                if (tp->usrsync < np->minsync) {
                                        tp->usrsync = np->minsync;
                                }
                        }
                        else
                                tp->usrsync = 255;
                }

                if (tp->usrwide > np->maxwide)
                        tp->usrwide = np->maxwide;

        }

        /*
        **    Start script processor.
        */
        if (np->paddr2) {
                if (bootverbose)
                        printk ("%s: Downloading SCSI SCRIPTS.\n",
                                ncr_name(np));
                OUTL (nc_scratcha, vtobus(np->script0));
                OUTL_DSP (NCB_SCRIPTH_PHYS (np, start_ram));
        }
        else
                OUTL_DSP (NCB_SCRIPT_PHYS (np, start));
}

/*==========================================================
**
**      Prepare the negotiation values for wide and
**      synchronous transfers.
**
**==========================================================
*/

static void ncr_negotiate (struct ncb* np, struct tcb* tp)
{
        /*
        **      minsync unit is 4ns !
        */

        u_long minsync = tp->usrsync;

        /*
        **      SCSI bus mode limit
        */

        if (np->scsi_mode && np->scsi_mode == SMODE_SE) {
                if (minsync < 12) minsync = 12;
        }

        /*
        **      our limit ..
        */

        if (minsync < np->minsync)
                minsync = np->minsync;

        /*
        **      divider limit
        */

        if (minsync > np->maxsync)
                minsync = 255;

        if (tp->maxoffs > np->maxoffs)
                tp->maxoffs = np->maxoffs;

        tp->minsync = minsync;
        tp->maxoffs = (minsync<255 ? tp->maxoffs : 0);

        /*
        **      period=0: has to negotiate sync transfer
        */

        tp->period=0;

        /*
        **      widedone=0: has to negotiate wide transfer
        */
        tp->widedone=0;
}

/*==========================================================
**
**      Get clock factor and sync divisor for a given 
**      synchronous factor period.
**      Returns the clock factor (in sxfer) and scntl3 
**      synchronous divisor field.
**
**==========================================================
*/

static void ncr_getsync(struct ncb *np, u_char sfac, u_char *fakp, u_char *scntl3p)
{
        u_long  clk = np->clock_khz;    /* SCSI clock frequency in kHz  */
        int     div = np->clock_divn;   /* Number of divisors supported */
        u_long  fak;                    /* Sync factor in sxfer         */
        u_long  per;                    /* Period in tenths of ns       */
        u_long  kpc;                    /* (per * clk)                  */

        /*
        **      Compute the synchronous period in tenths of nano-seconds
        */
        if      (sfac <= 10)    per = 250;
        else if (sfac == 11)    per = 303;
        else if (sfac == 12)    per = 500;
        else                    per = 40 * sfac;

        /*
        **      Look for the greatest clock divisor that allows an 
        **      input speed faster than the period.
        */
        kpc = per * clk;
        while (--div > 0)
                if (kpc >= (div_10M[div] << 2)) break;

        /*
        **      Calculate the lowest clock factor that allows an output 
        **      speed not faster than the period.
        */
        fak = (kpc - 1) / div_10M[div] + 1;

        if (fak < 4) fak = 4;   /* Should never happen, too bad ... */

        /*
        **      Compute and return sync parameters for the ncr
        */
        *fakp           = fak - 4;
        *scntl3p        = ((div+1) << 4) + (sfac < 25 ? 0x80 : 0);
}


/*==========================================================
**
**      Set actual values, sync status and patch all ccbs of 
**      a target according to new sync/wide agreement.
**
**==========================================================
*/

static void ncr_set_sync_wide_status (struct ncb *np, u_char target)
{
        struct ccb *cp;
        struct tcb *tp = &np->target[target];

        /*
        **      set actual value and sync_status
        */
        OUTB (nc_sxfer, tp->sval);
        np->sync_st = tp->sval;
        OUTB (nc_scntl3, tp->wval);
        np->wide_st = tp->wval;

        /*
        **      patch ALL ccbs of this target.
        */
        for (cp = np->ccb; cp; cp = cp->link_ccb) {
                if (!cp->cmd) continue;
                if (scmd_id(cp->cmd) != target) continue;
                cp->phys.select.sel_scntl3 = tp->wval;
                cp->phys.select.sel_sxfer  = tp->sval;
        }
}

/*==========================================================
**
**      Switch sync mode for current job and it's target
**
**==========================================================
*/

static void ncr_setsync (struct ncb *np, struct ccb *cp, u_char scntl3, u_char sxfer)
{
        struct scsi_cmnd *cmd = cp->cmd;
        struct tcb *tp;
        u_char target = INB (nc_sdid) & 0x0f;
        u_char idiv;

        BUG_ON(target != (scmd_id(cmd) & 0xf));

        tp = &np->target[target];

        if (!scntl3 || !(sxfer & 0x1f))
                scntl3 = np->rv_scntl3;
        scntl3 = (scntl3 & 0xf0) | (tp->wval & EWS) | (np->rv_scntl3 & 0x07);

        /*
        **      Deduce the value of controller sync period from scntl3.
        **      period is in tenths of nano-seconds.
        */

        idiv = ((scntl3 >> 4) & 0x7);
        if ((sxfer & 0x1f) && idiv)
                tp->period = (((sxfer>>5)+4)*div_10M[idiv-1])/np->clock_khz;
        else
                tp->period = 0xffff;

        /* Stop there if sync parameters are unchanged */
        if (tp->sval == sxfer && tp->wval == scntl3)
                return;
        tp->sval = sxfer;
        tp->wval = scntl3;

        if (sxfer & 0x01f) {
                /* Disable extended Sreq/Sack filtering */
                if (tp->period <= 2000)
                        OUTOFFB(nc_stest2, EXT);
        }
 
        spi_display_xfer_agreement(tp->starget);

        /*
        **      set actual value and sync_status
        **      patch ALL ccbs of this target.
        */
        ncr_set_sync_wide_status(np, target);
}

/*==========================================================
**
**      Switch wide mode for current job and it's target
**      SCSI specs say: a SCSI device that accepts a WDTR 
**      message shall reset the synchronous agreement to 
**      asynchronous mode.
**
**==========================================================
*/

static void ncr_setwide (struct ncb *np, struct ccb *cp, u_char wide, u_char ack)
{
        struct scsi_cmnd *cmd = cp->cmd;
        u16 target = INB (nc_sdid) & 0x0f;
        struct tcb *tp;
        u_char  scntl3;
        u_char  sxfer;

        BUG_ON(target != (scmd_id(cmd) & 0xf));

        tp = &np->target[target];
        tp->widedone  =  wide+1;
        scntl3 = (tp->wval & (~EWS)) | (wide ? EWS : 0);

        sxfer = ack ? 0 : tp->sval;

        /*
        **       Stop there if sync/wide parameters are unchanged
        */
        if (tp->sval == sxfer && tp->wval == scntl3) return;
        tp->sval = sxfer;
        tp->wval = scntl3;

        /*
        **      Bells and whistles   ;-)
        */
        if (bootverbose >= 2) {
                dev_info(&cmd->device->sdev_target->dev, "WIDE SCSI %sabled.\n",
                                (scntl3 & EWS) ? "en" : "dis");
        }

        /*
        **      set actual value and sync_status
        **      patch ALL ccbs of this target.
        */
        ncr_set_sync_wide_status(np, target);
}

/*==========================================================
**
**      Switch tagged mode for a target.
**
**==========================================================
*/

static void ncr_setup_tags (struct ncb *np, struct scsi_device *sdev)
{
        unsigned char tn = sdev->id, ln = sdev->lun;
        struct tcb *tp = &np->target[tn];
        struct lcb *lp = tp->lp[ln];
        u_char   reqtags, maxdepth;

        /*
        **      Just in case ...
        */
        if ((!tp) || (!lp) || !sdev)
                return;

        /*
        **      If SCSI device queue depth is not yet set, leave here.
        */
        if (!lp->scdev_depth)
                return;

        /*
        **      Donnot allow more tags than the SCSI driver can queue 
        **      for this device.
        **      Donnot allow more tags than we can handle.
        */
        maxdepth = lp->scdev_depth;
        if (maxdepth > lp->maxnxs)      maxdepth    = lp->maxnxs;
        if (lp->maxtags > maxdepth)     lp->maxtags = maxdepth;
        if (lp->numtags > maxdepth)     lp->numtags = maxdepth;

        /*
        **      only devices conformant to ANSI Version >= 2
        **      only devices capable of tagged commands
        **      only if enabled by user ..
        */
        if (sdev->tagged_supported && lp->numtags > 1) {
                reqtags = lp->numtags;
        } else {
                reqtags = 1;
        }

        /*
        **      Update max number of tags
        */
        lp->numtags = reqtags;
        if (lp->numtags > lp->maxtags)
                lp->maxtags = lp->numtags;

        /*
        **      If we want to switch tag mode, we must wait 
        **      for no CCB to be active.
        */
        if      (reqtags > 1 && lp->usetags) {   /* Stay in tagged mode    */
                if (lp->queuedepth == reqtags)   /* Already announced      */
                        return;
                lp->queuedepth  = reqtags;
        }
        else if (reqtags <= 1 && !lp->usetags) { /* Stay in untagged mode  */
                lp->queuedepth  = reqtags;
                return;
        }
        else {                                   /* Want to switch tag mode */
                if (lp->busyccbs)                /* If not yet safe, return */
                        return;
                lp->queuedepth  = reqtags;
                lp->usetags     = reqtags > 1 ? 1 : 0;
        }

        /*
        **      Patch the lun mini-script, according to tag mode.
        */
        lp->jump_tag.l_paddr = lp->usetags?
                        cpu_to_scr(NCB_SCRIPT_PHYS(np, resel_tag)) :
                        cpu_to_scr(NCB_SCRIPT_PHYS(np, resel_notag));

        /*
        **      Announce change to user.
        */
        if (bootverbose) {
                if (lp->usetags) {
                        dev_info(&sdev->sdev_gendev,
                                "tagged command queue depth set to %d\n",
                                reqtags);
                } else {
                        dev_info(&sdev->sdev_gendev,
                                        "tagged command queueing disabled\n");
                }
        }
}

/*==========================================================
**
**
**      ncr timeout handler.
**
**
**==========================================================
**
**      Misused to keep the driver running when
**      interrupts are not configured correctly.
**
**----------------------------------------------------------
*/

static void ncr_timeout (struct ncb *np)
{
        u_long  thistime = jiffies;

        /*
        **      If release process in progress, let's go
        **      Set the release stage from 1 to 2 to synchronize
        **      with the release process.
        */

        if (np->release_stage) {
                if (np->release_stage == 1) np->release_stage = 2;
                return;
        }

        np->timer.expires = jiffies + SCSI_NCR_TIMER_INTERVAL;
        add_timer(&np->timer);

        /*
        **      If we are resetting the ncr, wait for settle_time before 
        **      clearing it. Then command processing will be resumed.
        */
        if (np->settle_time) {
                if (np->settle_time <= thistime) {
                        if (bootverbose > 1)
                                printk("%s: command processing resumed\n", ncr_name(np));
                        np->settle_time = 0;
                        np->disc        = 1;
                        requeue_waiting_list(np);
                }
                return;
        }

        /*
        **      Since the generic scsi driver only allows us 0.5 second 
        **      to perform abort of a command, we must look at ccbs about 
        **      every 0.25 second.
        */
        if (np->lasttime + 4*HZ < thistime) {
                /*
                **      block ncr interrupts
                */
                np->lasttime = thistime;
        }

#ifdef SCSI_NCR_BROKEN_INTR
        if (INB(nc_istat) & (INTF|SIP|DIP)) {

                /*
                **      Process pending interrupts.
                */
                if (DEBUG_FLAGS & DEBUG_TINY) printk ("{");
                ncr_exception (np);
                if (DEBUG_FLAGS & DEBUG_TINY) printk ("}");
        }
#endif /* SCSI_NCR_BROKEN_INTR */
}

/*==========================================================
**
**      log message for real hard errors
**
**      "ncr0 targ 0?: ERROR (ds:si) (so-si-sd) (sxfer/scntl3) @ name (dsp:dbc)."
**      "             reg: r0 r1 r2 r3 r4 r5 r6 ..... rf."
**
**      exception register:
**              ds:     dstat
**              si:     sist
**
**      SCSI bus lines:
**              so:     control lines as driver by NCR.
**              si:     control lines as seen by NCR.
**              sd:     scsi data lines as seen by NCR.
**
**      wide/fastmode:
**              sxfer:  (see the manual)
**              scntl3: (see the manual)
**
**      current script command:
**              dsp:    script address (relative to start of script).
**              dbc:    first word of script command.
**
**      First 16 register of the chip:
**              r0..rf
**
**==========================================================
*/

static void ncr_log_hard_error(struct ncb *np, u16 sist, u_char dstat)
{
        u32     dsp;
        int     script_ofs;
        int     script_size;
        char    *script_name;
        u_char  *script_base;
        int     i;

        dsp     = INL (nc_dsp);

        if (dsp > np->p_script && dsp <= np->p_script + sizeof(struct script)) {
                script_ofs      = dsp - np->p_script;
                script_size     = sizeof(struct script);
                script_base     = (u_char *) np->script0;
                script_name     = "script";
        }
        else if (np->p_scripth < dsp && 
                 dsp <= np->p_scripth + sizeof(struct scripth)) {
                script_ofs      = dsp - np->p_scripth;
                script_size     = sizeof(struct scripth);
                script_base     = (u_char *) np->scripth0;
                script_name     = "scripth";
        } else {
                script_ofs      = dsp;
                script_size     = 0;
                script_base     = NULL;
                script_name     = "mem";
        }

        printk ("%s:%d: ERROR (%x:%x) (%x-%x-%x) (%x/%x) @ (%s %x:%08x).\n",
                ncr_name (np), (unsigned)INB (nc_sdid)&0x0f, dstat, sist,
                (unsigned)INB (nc_socl), (unsigned)INB (nc_sbcl), (unsigned)INB (nc_sbdl),
                (unsigned)INB (nc_sxfer),(unsigned)INB (nc_scntl3), script_name, script_ofs,
                (unsigned)INL (nc_dbc));

        if (((script_ofs & 3) == 0) &&
            (unsigned)script_ofs < script_size) {
                printk ("%s: script cmd = %08x\n", ncr_name(np),
                        scr_to_cpu((int) *(ncrcmd *)(script_base + script_ofs)));
        }

        printk ("%s: regdump:", ncr_name(np));
        for (i=0; i<16;i++)
            printk (" %02x", (unsigned)INB_OFF(i));
        printk (".\n");
}

/*============================================================
**
**      ncr chip exception handler.
**
**============================================================
**
**      In normal cases, interrupt conditions occur one at a 
**      time. The ncr is able to stack in some extra registers 
**      other interrupts that will occur after the first one.
**      But, several interrupts may occur at the same time.
**
**      We probably should only try to deal with the normal 
**      case, but it seems that multiple interrupts occur in 
**      some cases that are not abnormal at all.
**
**      The most frequent interrupt condition is Phase Mismatch.
**      We should want to service this interrupt quickly.
**      A SCSI parity error may be delivered at the same time.
**      The SIR interrupt is not very frequent in this driver, 
**      since the INTFLY is likely used for command completion 
**      signaling.
**      The Selection Timeout interrupt may be triggered with 
**      IID and/or UDC.
**      The SBMC interrupt (SCSI Bus Mode Change) may probably 
**      occur at any time.
**
**      This handler try to deal as cleverly as possible with all
**      the above.
**
**============================================================
*/

void ncr_exception (struct ncb *np)
{
        u_char  istat, dstat;
        u16     sist;
        int     i;

        /*
        **      interrupt on the fly ?
        **      Since the global header may be copied back to a CCB 
        **      using a posted PCI memory write, the last operation on 
        **      the istat register is a READ in order to flush posted 
        **      PCI write commands.
        */
        istat = INB (nc_istat);
        if (istat & INTF) {
                OUTB (nc_istat, (istat & SIGP) | INTF);
                istat = INB (nc_istat);
                if (DEBUG_FLAGS & DEBUG_TINY) printk ("F ");
                ncr_wakeup_done (np);
        }

        if (!(istat & (SIP|DIP)))
                return;

        if (istat & CABRT)
                OUTB (nc_istat, CABRT);

        /*
        **      Steinbach's Guideline for Systems Programming:
        **      Never test for an error condition you don't know how to handle.
        */

        sist  = (istat & SIP) ? INW (nc_sist)  : 0;
        dstat = (istat & DIP) ? INB (nc_dstat) : 0;

        if (DEBUG_FLAGS & DEBUG_TINY)
                printk ("<%d|%x:%x|%x:%x>",
                        (int)INB(nc_scr0),
                        dstat,sist,
                        (unsigned)INL(nc_dsp),
                        (unsigned)INL(nc_dbc));

        /*========================================================
        **      First, interrupts we want to service cleanly.
        **
        **      Phase mismatch is the most frequent interrupt, and 
        **      so we have to service it as quickly and as cleanly 
        **      as possible.
        **      Programmed interrupts are rarely used in this driver,
        **      but we must handle them cleanly anyway.
        **      We try to deal with PAR and SBMC combined with 
        **      some other interrupt(s).
        **=========================================================
        */

        if (!(sist  & (STO|GEN|HTH|SGE|UDC|RST)) &&
            !(dstat & (MDPE|BF|ABRT|IID))) {
                if ((sist & SBMC) && ncr_int_sbmc (np))
                        return;
                if ((sist & PAR)  && ncr_int_par  (np))
                        return;
                if (sist & MA) {
                        ncr_int_ma (np);
                        return;
                }
                if (dstat & SIR) {
                        ncr_int_sir (np);
                        return;
                }
                /*
                **  DEL 397 - 53C875 Rev 3 - Part Number 609-0392410 - ITEM 2.
                */
                if (!(sist & (SBMC|PAR)) && !(dstat & SSI)) {
                        printk( "%s: unknown interrupt(s) ignored, "
                                "ISTAT=%x DSTAT=%x SIST=%x\n",
                                ncr_name(np), istat, dstat, sist);
                        return;
                }
                OUTONB_STD ();
                return;
        }

        /*========================================================
        **      Now, interrupts that need some fixing up.
        **      Order and multiple interrupts is so less important.
        **
        **      If SRST has been asserted, we just reset the chip.
        **
        **      Selection is intirely handled by the chip. If the 
        **      chip says STO, we trust it. Seems some other 
        **      interrupts may occur at the same time (UDC, IID), so 
        **      we ignore them. In any case we do enough fix-up 
        **      in the service routine.
        **      We just exclude some fatal dma errors.
        **=========================================================
        */

        if (sist & RST) {
                ncr_init (np, 1, bootverbose ? "scsi reset" : NULL, HS_RESET);
                return;
        }

        if ((sist & STO) &&
                !(dstat & (MDPE|BF|ABRT))) {
        /*
        **      DEL 397 - 53C875 Rev 3 - Part Number 609-0392410 - ITEM 1.
        */
                OUTONB (nc_ctest3, CLF);

                ncr_int_sto (np);
                return;
        }

        /*=========================================================
        **      Now, interrupts we are not able to recover cleanly.
        **      (At least for the moment).
        **
        **      Do the register dump.
        **      Log message for real hard errors.
        **      Clear all fifos.
        **      For MDPE, BF, ABORT, IID, SGE and HTH we reset the 
        **      BUS and the chip.
        **      We are more soft for UDC.
        **=========================================================
        */

        if (time_after(jiffies, np->regtime)) {
                np->regtime = jiffies + 10*HZ;
                for (i = 0; i<sizeof(np->regdump); i++)
                        ((char*)&np->regdump)[i] = INB_OFF(i);
                np->regdump.nc_dstat = dstat;
                np->regdump.nc_sist  = sist;
        }

        ncr_log_hard_error(np, sist, dstat);

        printk ("%s: have to clear fifos.\n", ncr_name (np));
        OUTB (nc_stest3, TE|CSF);
        OUTONB (nc_ctest3, CLF);

        if ((sist & (SGE)) ||
                (dstat & (MDPE|BF|ABRT|IID))) {
                ncr_start_reset(np);
                return;
        }

        if (sist & HTH) {
                printk ("%s: handshake timeout\n", ncr_name(np));
                ncr_start_reset(np);
                return;
        }

        if (sist & UDC) {
                printk ("%s: unexpected disconnect\n", ncr_name(np));
                OUTB (HS_PRT, HS_UNEXPECTED);
                OUTL_DSP (NCB_SCRIPT_PHYS (np, cleanup));
                return;
        }

        /*=========================================================
        **      We just miss the cause of the interrupt. :(
        **      Print a message. The timeout will do the real work.
        **=========================================================
        */
        printk ("%s: unknown interrupt\n", ncr_name(np));
}

/*==========================================================
**
**      ncr chip exception handler for selection timeout
**
**==========================================================
**
**      There seems to be a bug in the 53c810.
**      Although a STO-Interrupt is pending,
**      it continues executing script commands.
**      But it will fail and interrupt (IID) on
**      the next instruction where it's looking
**      for a valid phase.
**
**----------------------------------------------------------
*/

void ncr_int_sto (struct ncb *np)
{
        u_long dsa;
        struct ccb *cp;
        if (DEBUG_FLAGS & DEBUG_TINY) printk ("T");

        /*
        **      look for ccb and set the status.
        */

        dsa = INL (nc_dsa);
        cp = np->ccb;
        while (cp && (CCB_PHYS (cp, phys) != dsa))
                cp = cp->link_ccb;

        if (cp) {
                cp-> host_status = HS_SEL_TIMEOUT;
                ncr_complete (np, cp);
        }

        /*
        **      repair start queue and jump to start point.
        */

        OUTL_DSP (NCB_SCRIPTH_PHYS (np, sto_restart));
        return;
}

/*==========================================================
**
**      ncr chip exception handler for SCSI bus mode change
**
**==========================================================
**
**      spi2-r12 11.2.3 says a transceiver mode change must 
**      generate a reset event and a device that detects a reset 
**      event shall initiate a hard reset. It says also that a
**      device that detects a mode change shall set data transfer 
**      mode to eight bit asynchronous, etc...
**      So, just resetting should be enough.
**       
**
**----------------------------------------------------------
*/

static int ncr_int_sbmc (struct ncb *np)
{
        u_char scsi_mode = INB (nc_stest4) & SMODE;

        if (scsi_mode != np->scsi_mode) {
                printk("%s: SCSI bus mode change from %x to %x.\n",
                        ncr_name(np), np->scsi_mode, scsi_mode);

                np->scsi_mode = scsi_mode;


                /*
                **      Suspend command processing for 1 second and 
                **      reinitialize all except the chip.
                */
                np->settle_time = jiffies + HZ;
                ncr_init (np, 0, bootverbose ? "scsi mode change" : NULL, HS_RESET);
                return 1;
        }
        return 0;
}

/*==========================================================
**
**      ncr chip exception handler for SCSI parity error.
**
**==========================================================
**
**
**----------------------------------------------------------
*/

static int ncr_int_par (struct ncb *np)
{
        u_char  hsts    = INB (HS_PRT);
        u32     dbc     = INL (nc_dbc);
        u_char  sstat1  = INB (nc_sstat1);
        int phase       = -1;
        int msg         = -1;
        u32 jmp;

        printk("%s: SCSI parity error detected: SCR1=%d DBC=%x SSTAT1=%x\n",
                ncr_name(np), hsts, dbc, sstat1);

        /*
         *      Ignore the interrupt if the NCR is not connected 
         *      to the SCSI bus, since the right work should have  
         *      been done on unexpected disconnection handling.
         */
        if (!(INB (nc_scntl1) & ISCON))
                return 0;

        /*
         *      If the nexus is not clearly identified, reset the bus.
         *      We will try to do better later.
         */
        if (hsts & HS_INVALMASK)
                goto reset_all;

        /*
         *      If the SCSI parity error occurs in MSG IN phase, prepare a 
         *      MSG PARITY message. Otherwise, prepare a INITIATOR DETECTED 
         *      ERROR message and let the device decide to retry the command 
         *      or to terminate with check condition. If we were in MSG IN 
         *      phase waiting for the response of a negotiation, we will 
         *      get SIR_NEGO_FAILED at dispatch.
         */
        if (!(dbc & 0xc0000000))
                phase = (dbc >> 24) & 7;
        if (phase == 7)
                msg = MSG_PARITY_ERROR;
        else
                msg = INITIATOR_ERROR;


        /*
         *      If the NCR stopped on a MOVE ^ DATA_IN, we jump to a 
         *      script that will ignore all data in bytes until phase 
         *      change, since we are not sure the chip will wait the phase 
         *      change prior to delivering the interrupt.
         */
        if (phase == 1)
                jmp = NCB_SCRIPTH_PHYS (np, par_err_data_in);
        else
                jmp = NCB_SCRIPTH_PHYS (np, par_err_other);

        OUTONB (nc_ctest3, CLF );       /* clear dma fifo  */
        OUTB (nc_stest3, TE|CSF);       /* clear scsi fifo */

        np->msgout[0] = msg;
        OUTL_DSP (jmp);
        return 1;

reset_all:
        ncr_start_reset(np);
        return 1;
}

/*==========================================================
**
**
**      ncr chip exception handler for phase errors.
**
**
**==========================================================
**
**      We have to construct a new transfer descriptor,
**      to transfer the rest of the current block.
**
**----------------------------------------------------------
*/

static void ncr_int_ma (struct ncb *np)
{
        u32     dbc;
        u32     rest;
        u32     dsp;
        u32     dsa;
        u32     nxtdsp;
        u32     newtmp;
        u32     *vdsp;
        u32     oadr, olen;
        u32     *tblp;
        ncrcmd *newcmd;
        u_char  cmd, sbcl;
        struct ccb *cp;

        dsp     = INL (nc_dsp);
        dbc     = INL (nc_dbc);
        sbcl    = INB (nc_sbcl);

        cmd     = dbc >> 24;
        rest    = dbc & 0xffffff;

        /*
        **      Take into account dma fifo and various buffers and latches,
        **      only if the interrupted phase is an OUTPUT phase.
        */

        if ((cmd & 1) == 0) {
                u_char  ctest5, ss0, ss2;
                u16     delta;

                ctest5 = (np->rv_ctest5 & DFS) ? INB (nc_ctest5) : 0;
                if (ctest5 & DFS)
                        delta=(((ctest5 << 8) | (INB (nc_dfifo) & 0xff)) - rest) & 0x3ff;
                else
                        delta=(INB (nc_dfifo) - rest) & 0x7f;

                /*
                **      The data in the dma fifo has not been transferred to
                **      the target -> add the amount to the rest
                **      and clear the data.
                **      Check the sstat2 register in case of wide transfer.
                */

                rest += delta;
                ss0  = INB (nc_sstat0);
                if (ss0 & OLF) rest++;
                if (ss0 & ORF) rest++;
                if (INB(nc_scntl3) & EWS) {
                        ss2 = INB (nc_sstat2);
                        if (ss2 & OLF1) rest++;
                        if (ss2 & ORF1) rest++;
                }

                if (DEBUG_FLAGS & (DEBUG_TINY|DEBUG_PHASE))
                        printk ("P%x%x RL=%d D=%d SS0=%x ", cmd&7, sbcl&7,
                                (unsigned) rest, (unsigned) delta, ss0);

        } else  {
                if (DEBUG_FLAGS & (DEBUG_TINY|DEBUG_PHASE))
                        printk ("P%x%x RL=%d ", cmd&7, sbcl&7, rest);
        }

        /*
        **      Clear fifos.
        */
        OUTONB (nc_ctest3, CLF );       /* clear dma fifo  */
        OUTB (nc_stest3, TE|CSF);       /* clear scsi fifo */

        /*
        **      locate matching cp.
        **      if the interrupted phase is DATA IN or DATA OUT,
        **      trust the global header.
        */
        dsa = INL (nc_dsa);
        if (!(cmd & 6)) {
                cp = np->header.cp;
                if (CCB_PHYS(cp, phys) != dsa)
                        cp = NULL;
        } else {
                cp  = np->ccb;
                while (cp && (CCB_PHYS (cp, phys) != dsa))
                        cp = cp->link_ccb;
        }

        /*
        **      try to find the interrupted script command,
        **      and the address at which to continue.
        */
        vdsp    = NULL;
        nxtdsp  = 0;
        if      (dsp >  np->p_script &&
                 dsp <= np->p_script + sizeof(struct script)) {
                vdsp = (u32 *)((char*)np->script0 + (dsp-np->p_script-8));
                nxtdsp = dsp;
        }
        else if (dsp >  np->p_scripth &&
                 dsp <= np->p_scripth + sizeof(struct scripth)) {
                vdsp = (u32 *)((char*)np->scripth0 + (dsp-np->p_scripth-8));
                nxtdsp = dsp;
        }
        else if (cp) {
                if      (dsp == CCB_PHYS (cp, patch[2])) {
                        vdsp = &cp->patch[0];
                        nxtdsp = scr_to_cpu(vdsp[3]);
                }
                else if (dsp == CCB_PHYS (cp, patch[6])) {
                        vdsp = &cp->patch[4];
                        nxtdsp = scr_to_cpu(vdsp[3]);
                }
        }

        /*
        **      log the information
        */

        if (DEBUG_FLAGS & DEBUG_PHASE) {
                printk ("\nCP=%p CP2=%p DSP=%x NXT=%x VDSP=%p CMD=%x ",
                        cp, np->header.cp,
                        (unsigned)dsp,
                        (unsigned)nxtdsp, vdsp, cmd);
        }

        /*
        **      cp=0 means that the DSA does not point to a valid control 
        **      block. This should not happen since we donnot use multi-byte 
        **      move while we are being reselected ot after command complete.
        **      We are not able to recover from such a phase error.
        */
        if (!cp) {
                printk ("%s: SCSI phase error fixup: "
                        "CCB already dequeued (0x%08lx)\n", 
                        ncr_name (np), (u_long) np->header.cp);
                goto reset_all;
        }

        /*
        **      get old startaddress and old length.
        */

        oadr = scr_to_cpu(vdsp[1]);

        if (cmd & 0x10) {       /* Table indirect */
                tblp = (u32 *) ((char*) &cp->phys + oadr);
                olen = scr_to_cpu(tblp[0]);
                oadr = scr_to_cpu(tblp[1]);
        } else {
                tblp = (u32 *) 0;
                olen = scr_to_cpu(vdsp[0]) & 0xffffff;
        }

        if (DEBUG_FLAGS & DEBUG_PHASE) {
                printk ("OCMD=%x\nTBLP=%p OLEN=%x OADR=%x\n",
                        (unsigned) (scr_to_cpu(vdsp[0]) >> 24),
                        tblp,
                        (unsigned) olen,
                        (unsigned) oadr);
        }

        /*
        **      check cmd against assumed interrupted script command.
        */

        if (cmd != (scr_to_cpu(vdsp[0]) >> 24)) {
                PRINT_ADDR(cp->cmd, "internal error: cmd=%02x != %02x=(vdsp[0] "
                                ">> 24)\n", cmd, scr_to_cpu(vdsp[0]) >> 24);

                goto reset_all;
        }

        /*
        **      cp != np->header.cp means that the header of the CCB 
        **      currently being processed has not yet been copied to 
        **      the global header area. That may happen if the device did 
        **      not accept all our messages after having been selected.
        */
        if (cp != np->header.cp) {
                printk ("%s: SCSI phase error fixup: "
                        "CCB address mismatch (0x%08lx != 0x%08lx)\n", 
                        ncr_name (np), (u_long) cp, (u_long) np->header.cp);
        }

        /*
        **      if old phase not dataphase, leave here.
        */

        if (cmd & 0x06) {
                PRINT_ADDR(cp->cmd, "phase change %x-%x %d@%08x resid=%d.\n",
                        cmd&7, sbcl&7, (unsigned)olen,
                        (unsigned)oadr, (unsigned)rest);
                goto unexpected_phase;
        }

        /*
        **      choose the correct patch area.
        **      if savep points to one, choose the other.
        */

        newcmd = cp->patch;
        newtmp = CCB_PHYS (cp, patch);
        if (newtmp == scr_to_cpu(cp->phys.header.savep)) {
                newcmd = &cp->patch[4];
                newtmp = CCB_PHYS (cp, patch[4]);
        }

        /*
        **      fillin the commands
        */

        newcmd[0] = cpu_to_scr(((cmd & 0x0f) << 24) | rest);
        newcmd[1] = cpu_to_scr(oadr + olen - rest);
        newcmd[2] = cpu_to_scr(SCR_JUMP);
        newcmd[3] = cpu_to_scr(nxtdsp);

        if (DEBUG_FLAGS & DEBUG_PHASE) {
                PRINT_ADDR(cp->cmd, "newcmd[%d] %x %x %x %x.\n",
                        (int) (newcmd - cp->patch),
                        (unsigned)scr_to_cpu(newcmd[0]),
                        (unsigned)scr_to_cpu(newcmd[1]),
                        (unsigned)scr_to_cpu(newcmd[2]),
                        (unsigned)scr_to_cpu(newcmd[3]));
        }
        /*
        **      fake the return address (to the patch).
        **      and restart script processor at dispatcher.
        */
        OUTL (nc_temp, newtmp);
        OUTL_DSP (NCB_SCRIPT_PHYS (np, dispatch));
        return;

        /*
        **      Unexpected phase changes that occurs when the current phase 
        **      is not a DATA IN or DATA OUT phase are due to error conditions.
        **      Such event may only happen when the SCRIPTS is using a 
        **      multibyte SCSI MOVE.
        **
        **      Phase change            Some possible cause
        **
        **      COMMAND  --> MSG IN     SCSI parity error detected by target.
        **      COMMAND  --> STATUS     Bad command or refused by target.
        **      MSG OUT  --> MSG IN     Message rejected by target.
        **      MSG OUT  --> COMMAND    Bogus target that discards extended
        **                              negotiation messages.
        **
        **      The code below does not care of the new phase and so 
        **      trusts the target. Why to annoy it ?
        **      If the interrupted phase is COMMAND phase, we restart at
        **      dispatcher.
        **      If a target does not get all the messages after selection, 
        **      the code assumes blindly that the target discards extended 
        **      messages and clears the negotiation status.
        **      If the target does not want all our response to negotiation,
        **      we force a SIR_NEGO_PROTO interrupt (it is a hack that avoids 
        **      bloat for such a should_not_happen situation).
        **      In all other situation, we reset the BUS.
        **      Are these assumptions reasonable ? (Wait and see ...)
        */
unexpected_phase:
        dsp -= 8;
        nxtdsp = 0;

        switch (cmd & 7) {
        case 2: /* COMMAND phase */
                nxtdsp = NCB_SCRIPT_PHYS (np, dispatch);
                break;
#if 0
        case 3: /* STATUS  phase */
                nxtdsp = NCB_SCRIPT_PHYS (np, dispatch);
                break;
#endif
        case 6: /* MSG OUT phase */
                np->scripth->nxtdsp_go_on[0] = cpu_to_scr(dsp + 8);
                if      (dsp == NCB_SCRIPT_PHYS (np, send_ident)) {
                        cp->host_status = HS_BUSY;
                        nxtdsp = NCB_SCRIPTH_PHYS (np, clratn_go_on);
                }
                else if (dsp == NCB_SCRIPTH_PHYS (np, send_wdtr) ||
                         dsp == NCB_SCRIPTH_PHYS (np, send_sdtr)) {
                        nxtdsp = NCB_SCRIPTH_PHYS (np, nego_bad_phase);
                }
                break;
#if 0
        case 7: /* MSG IN  phase */
                nxtdsp = NCB_SCRIPT_PHYS (np, clrack);
                break;
#endif
        }

        if (nxtdsp) {
                OUTL_DSP (nxtdsp);
                return;
        }

reset_all:
        ncr_start_reset(np);
}


static void ncr_sir_to_redo(struct ncb *np, int num, struct ccb *cp)
{
        struct scsi_cmnd *cmd   = cp->cmd;
        struct tcb *tp  = &np->target[cmd->device->id];
        struct lcb *lp  = tp->lp[cmd->device->lun];
        struct list_head *qp;
        struct ccb *    cp2;
        int             disc_cnt = 0;
        int             busy_cnt = 0;
        u32             startp;
        u_char          s_status = INB (SS_PRT);

        /*
        **      Let the SCRIPTS processor skip all not yet started CCBs,
        **      and count disconnected CCBs. Since the busy queue is in 
        **      the same order as the chip start queue, disconnected CCBs 
        **      are before cp and busy ones after.
        */
        if (lp) {
                qp = lp->busy_ccbq.prev;
                while (qp != &lp->busy_ccbq) {
                        cp2 = list_entry(qp, struct ccb, link_ccbq);
                        qp  = qp->prev;
                        ++busy_cnt;
                        if (cp2 == cp)
                                break;
                        cp2->start.schedule.l_paddr =
                        cpu_to_scr(NCB_SCRIPTH_PHYS (np, skip));
                }
                lp->held_ccb = cp;      /* Requeue when this one completes */
                disc_cnt = lp->queuedccbs - busy_cnt;
        }

        switch(s_status) {
        default:        /* Just for safety, should never happen */
        case SAM_STAT_TASK_SET_FULL:
                /*
                **      Decrease number of tags to the number of 
                **      disconnected commands.
                */
                if (!lp)
                        goto out;
                if (bootverbose >= 1) {
                        PRINT_ADDR(cmd, "QUEUE FULL! %d busy, %d disconnected "
                                        "CCBs\n", busy_cnt, disc_cnt);
                }
                if (disc_cnt < lp->numtags) {
                        lp->numtags     = disc_cnt > 2 ? disc_cnt : 2;
                        lp->num_good    = 0;
                        ncr_setup_tags (np, cmd->device);
                }
                /*
                **      Requeue the command to the start queue.
                **      If any disconnected commands,
                **              Clear SIGP.
                **              Jump to reselect.
                */
                cp->phys.header.savep = cp->startp;
                cp->host_status = HS_BUSY;
                cp->scsi_status = SAM_STAT_ILLEGAL;

                ncr_put_start_queue(np, cp);
                if (disc_cnt)
                        INB (nc_ctest2);                /* Clear SIGP */
                OUTL_DSP (NCB_SCRIPT_PHYS (np, reselect));
                return;
        case SAM_STAT_COMMAND_TERMINATED:
        case SAM_STAT_CHECK_CONDITION:
                /*
                **      If we were requesting sense, give up.
                */
                if (cp->auto_sense)
                        goto out;

                /*
                **      Device returned CHECK CONDITION status.
                **      Prepare all needed data strutures for getting 
                **      sense data.
                **
                **      identify message
                */
                cp->scsi_smsg2[0]       = IDENTIFY(0, cmd->device->lun);
                cp->phys.smsg.addr      = cpu_to_scr(CCB_PHYS (cp, scsi_smsg2));
                cp->phys.smsg.size      = cpu_to_scr(1);

                /*
                **      sense command
                */
                cp->phys.cmd.addr       = cpu_to_scr(CCB_PHYS (cp, sensecmd));
                cp->phys.cmd.size       = cpu_to_scr(6);

                /*
                **      patch requested size into sense command
                */
                cp->sensecmd[0]         = 0x03;
                cp->sensecmd[1]         = (cmd->device->lun & 0x7) << 5;
                cp->sensecmd[4]         = sizeof(cp->sense_buf);

                /*
                **      sense data
                */
                memset(cp->sense_buf, 0, sizeof(cp->sense_buf));
                cp->phys.sense.addr     = cpu_to_scr(CCB_PHYS(cp,sense_buf[0]));
                cp->phys.sense.size     = cpu_to_scr(sizeof(cp->sense_buf));

                /*
                **      requeue the command.
                */
                startp = cpu_to_scr(NCB_SCRIPTH_PHYS (np, sdata_in));

                cp->phys.header.savep   = startp;
                cp->phys.header.goalp   = startp + 24;
                cp->phys.header.lastp   = startp;
                cp->phys.header.wgoalp  = startp + 24;
                cp->phys.header.wlastp  = startp;

                cp->host_status = HS_BUSY;
                cp->scsi_status = SAM_STAT_ILLEGAL;
                cp->auto_sense  = s_status;

                cp->start.schedule.l_paddr =
                        cpu_to_scr(NCB_SCRIPT_PHYS (np, select));

                /*
                **      Select without ATN for quirky devices.
                */
                if (cmd->device->select_no_atn)
                        cp->start.schedule.l_paddr =
                        cpu_to_scr(NCB_SCRIPTH_PHYS (np, select_no_atn));

                ncr_put_start_queue(np, cp);

                OUTL_DSP (NCB_SCRIPT_PHYS (np, start));
                return;
        }

out:
        OUTONB_STD ();
        return;
}


/*==========================================================
**
**
**      ncr chip exception handler for programmed interrupts.
**
**
**==========================================================
*/

void ncr_int_sir (struct ncb *np)
{
        u_char scntl3;
        u_char chg, ofs, per, fak, wide;
        u_char num = INB (nc_dsps);
        struct ccb *cp=NULL;
        u_long  dsa    = INL (nc_dsa);
        u_char  target = INB (nc_sdid) & 0x0f;
        struct tcb *tp     = &np->target[target];
        struct scsi_target *starget = tp->starget;

        if (DEBUG_FLAGS & DEBUG_TINY) printk ("I#%d", num);

        switch (num) {
        case SIR_INTFLY:
                /*
                **      This is used for HP Zalon/53c720 where INTFLY
                **      operation is currently broken.
                */
                ncr_wakeup_done(np);
#ifdef SCSI_NCR_CCB_DONE_SUPPORT
                OUTL(nc_dsp, NCB_SCRIPT_PHYS (np, done_end) + 8);
#else
                OUTL(nc_dsp, NCB_SCRIPT_PHYS (np, start));
#endif
                return;
        case SIR_RESEL_NO_MSG_IN:
        case SIR_RESEL_NO_IDENTIFY:
                /*
                **      If devices reselecting without sending an IDENTIFY 
                **      message still exist, this should help.
                **      We just assume lun=0, 1 CCB, no tag.
                */
                if (tp->lp[0]) { 
                        OUTL_DSP (scr_to_cpu(tp->lp[0]->jump_ccb[0]));
                        return;
                }
                fallthrough;
        case SIR_RESEL_BAD_TARGET:      /* Will send a TARGET RESET message */
        case SIR_RESEL_BAD_LUN:         /* Will send a TARGET RESET message */
        case SIR_RESEL_BAD_I_T_L_Q:     /* Will send an ABORT TAG message   */
        case SIR_RESEL_BAD_I_T_L:       /* Will send an ABORT message       */
                printk ("%s:%d: SIR %d, "
                        "incorrect nexus identification on reselection\n",
                        ncr_name (np), target, num);
                goto out;
        case SIR_DONE_OVERFLOW:
                printk ("%s:%d: SIR %d, "
                        "CCB done queue overflow\n",
                        ncr_name (np), target, num);
                goto out;
        case SIR_BAD_STATUS:
                cp = np->header.cp;
                if (!cp || CCB_PHYS (cp, phys) != dsa)
                        goto out;
                ncr_sir_to_redo(np, num, cp);
                return;
        default:
                /*
                **      lookup the ccb
                */
                cp = np->ccb;
                while (cp && (CCB_PHYS (cp, phys) != dsa))
                        cp = cp->link_ccb;

                BUG_ON(!cp);
                BUG_ON(cp != np->header.cp);

                if (!cp || cp != np->header.cp)
                        goto out;
        }

        switch (num) {
/*-----------------------------------------------------------------------------
**
**      Was Sie schon immer ueber transfermode negotiation wissen wollten ...
**      ("Everything you've always wanted to know about transfer mode
**        negotiation")
**
**      We try to negotiate sync and wide transfer only after
**      a successful inquire command. We look at byte 7 of the
**      inquire data to determine the capabilities of the target.
**
**      When we try to negotiate, we append the negotiation message
**      to the identify and (maybe) simple tag message.
**      The host status field is set to HS_NEGOTIATE to mark this
**      situation.
**
**      If the target doesn't answer this message immediately
**      (as required by the standard), the SIR_NEGO_FAIL interrupt
**      will be raised eventually.
**      The handler removes the HS_NEGOTIATE status, and sets the
**      negotiated value to the default (async / nowide).
**
**      If we receive a matching answer immediately, we check it
**      for validity, and set the values.
**
**      If we receive a Reject message immediately, we assume the
**      negotiation has failed, and fall back to standard values.
**
**      If we receive a negotiation message while not in HS_NEGOTIATE
**      state, it's a target initiated negotiation. We prepare a
**      (hopefully) valid answer, set our parameters, and send back 
**      this answer to the target.
**
**      If the target doesn't fetch the answer (no message out phase),
**      we assume the negotiation has failed, and fall back to default
**      settings.
**
**      When we set the values, we adjust them in all ccbs belonging 
**      to this target, in the controller's register, and in the "phys"
**      field of the controller's struct ncb.
**
**      Possible cases:            hs  sir   msg_in value  send   goto
**      We try to negotiate:
**      -> target doesn't msgin    NEG FAIL  noop   defa.  -      dispatch
**      -> target rejected our msg NEG FAIL  reject defa.  -      dispatch
**      -> target answered  (ok)   NEG SYNC  sdtr   set    -      clrack
**      -> target answered (!ok)   NEG SYNC  sdtr   defa.  REJ--->msg_bad
**      -> target answered  (ok)   NEG WIDE  wdtr   set    -      clrack
**      -> target answered (!ok)   NEG WIDE  wdtr   defa.  REJ--->msg_bad
**      -> any other msgin         NEG FAIL  noop   defa.  -      dispatch
**
**      Target tries to negotiate:
**      -> incoming message        --- SYNC  sdtr   set    SDTR   -
**      -> incoming message        --- WIDE  wdtr   set    WDTR   -
**      We sent our answer:
**      -> target doesn't msgout   --- PROTO ?      defa.  -      dispatch
**
**-----------------------------------------------------------------------------
*/

        case SIR_NEGO_FAILED:
                /*-------------------------------------------------------
                **
                **      Negotiation failed.
                **      Target doesn't send an answer message,
                **      or target rejected our message.
                **
                **      Remove negotiation request.
                **
                **-------------------------------------------------------
                */
                OUTB (HS_PRT, HS_BUSY);

                fallthrough;

        case SIR_NEGO_PROTO:
                /*-------------------------------------------------------
                **
                **      Negotiation failed.
                **      Target doesn't fetch the answer message.
                **
                **-------------------------------------------------------
                */

                if (DEBUG_FLAGS & DEBUG_NEGO) {
                        PRINT_ADDR(cp->cmd, "negotiation failed sir=%x "
                                        "status=%x.\n", num, cp->nego_status);
                }

                /*
                **      any error in negotiation:
                **      fall back to default mode.
                */
                switch (cp->nego_status) {

                case NS_SYNC:
                        spi_period(starget) = 0;
                        spi_offset(starget) = 0;
                        ncr_setsync (np, cp, 0, 0xe0);
                        break;

                case NS_WIDE:
                        spi_width(starget) = 0;
                        ncr_setwide (np, cp, 0, 0);
                        break;

                }
                np->msgin [0] = NOP;
                np->msgout[0] = NOP;
                cp->nego_status = 0;
                break;

        case SIR_NEGO_SYNC:
                if (DEBUG_FLAGS & DEBUG_NEGO) {
                        ncr_print_msg(cp, "sync msgin", np->msgin);
                }

                chg = 0;
                per = np->msgin[3];
                ofs = np->msgin[4];
                if (ofs==0) per=255;

                /*
                **      if target sends SDTR message,
                **            it CAN transfer synch.
                */

                if (ofs && starget)
                        spi_support_sync(starget) = 1;

                /*
                **      check values against driver limits.
                */

                if (per < np->minsync)
                        {chg = 1; per = np->minsync;}
                if (per < tp->minsync)
                        {chg = 1; per = tp->minsync;}
                if (ofs > tp->maxoffs)
                        {chg = 1; ofs = tp->maxoffs;}

                /*
                **      Check against controller limits.
                */
                fak     = 7;
                scntl3  = 0;
                if (ofs != 0) {
                        ncr_getsync(np, per, &fak, &scntl3);
                        if (fak > 7) {
                                chg = 1;
                                ofs = 0;
                        }
                }
                if (ofs == 0) {
                        fak     = 7;
                        per     = 0;
                        scntl3  = 0;
                        tp->minsync = 0;
                }

                if (DEBUG_FLAGS & DEBUG_NEGO) {
                        PRINT_ADDR(cp->cmd, "sync: per=%d scntl3=0x%x ofs=%d "
                                "fak=%d chg=%d.\n", per, scntl3, ofs, fak, chg);
                }

                if (INB (HS_PRT) == HS_NEGOTIATE) {
                        OUTB (HS_PRT, HS_BUSY);
                        switch (cp->nego_status) {

                        case NS_SYNC:
                                /* This was an answer message */
                                if (chg) {
                                        /* Answer wasn't acceptable.  */
                                        spi_period(starget) = 0;
                                        spi_offset(starget) = 0;
                                        ncr_setsync(np, cp, 0, 0xe0);
                                        OUTL_DSP(NCB_SCRIPT_PHYS (np, msg_bad));
                                } else {
                                        /* Answer is ok.  */
                                        spi_period(starget) = per;
                                        spi_offset(starget) = ofs;
                                        ncr_setsync(np, cp, scntl3, (fak<<5)|ofs);
                                        OUTL_DSP(NCB_SCRIPT_PHYS (np, clrack));
                                }
                                return;

                        case NS_WIDE:
                                spi_width(starget) = 0;
                                ncr_setwide(np, cp, 0, 0);
                                break;
                        }
                }

                /*
                **      It was a request. Set value and
                **      prepare an answer message
                */

                spi_period(starget) = per;
                spi_offset(starget) = ofs;
                ncr_setsync(np, cp, scntl3, (fak<<5)|ofs);

                spi_populate_sync_msg(np->msgout, per, ofs);
                cp->nego_status = NS_SYNC;

                if (DEBUG_FLAGS & DEBUG_NEGO) {
                        ncr_print_msg(cp, "sync msgout", np->msgout);
                }

                if (!ofs) {
                        OUTL_DSP (NCB_SCRIPT_PHYS (np, msg_bad));
                        return;
                }
                np->msgin [0] = NOP;

                break;

        case SIR_NEGO_WIDE:
                /*
                **      Wide request message received.
                */
                if (DEBUG_FLAGS & DEBUG_NEGO) {
                        ncr_print_msg(cp, "wide msgin", np->msgin);
                }

                /*
                **      get requested values.
                */

                chg  = 0;
                wide = np->msgin[3];

                /*
                **      if target sends WDTR message,
                **            it CAN transfer wide.
                */

                if (wide && starget)
                        spi_support_wide(starget) = 1;

                /*
                **      check values against driver limits.
                */

                if (wide > tp->usrwide)
                        {chg = 1; wide = tp->usrwide;}

                if (DEBUG_FLAGS & DEBUG_NEGO) {
                        PRINT_ADDR(cp->cmd, "wide: wide=%d chg=%d.\n", wide,
                                        chg);
                }

                if (INB (HS_PRT) == HS_NEGOTIATE) {
                        OUTB (HS_PRT, HS_BUSY);
                        switch (cp->nego_status) {

                        case NS_WIDE:
                                /*
                                **      This was an answer message
                                */
                                if (chg) {
                                        /* Answer wasn't acceptable.  */
                                        spi_width(starget) = 0;
                                        ncr_setwide(np, cp, 0, 1);
                                        OUTL_DSP (NCB_SCRIPT_PHYS (np, msg_bad));
                                } else {
                                        /* Answer is ok.  */
                                        spi_width(starget) = wide;
                                        ncr_setwide(np, cp, wide, 1);
                                        OUTL_DSP (NCB_SCRIPT_PHYS (np, clrack));
                                }
                                return;

                        case NS_SYNC:
                                spi_period(starget) = 0;
                                spi_offset(starget) = 0;
                                ncr_setsync(np, cp, 0, 0xe0);
                                break;
                        }
                }

                /*
                **      It was a request, set value and
                **      prepare an answer message
                */

                spi_width(starget) = wide;
                ncr_setwide(np, cp, wide, 1);
                spi_populate_width_msg(np->msgout, wide);

                np->msgin [0] = NOP;

                cp->nego_status = NS_WIDE;

                if (DEBUG_FLAGS & DEBUG_NEGO) {
                        ncr_print_msg(cp, "wide msgout", np->msgin);
                }
                break;

/*--------------------------------------------------------------------
**
**      Processing of special messages
**
**--------------------------------------------------------------------
*/

        case SIR_REJECT_RECEIVED:
                /*-----------------------------------------------
                **
                **      We received a MESSAGE_REJECT.
                **
                **-----------------------------------------------
                */

                PRINT_ADDR(cp->cmd, "MESSAGE_REJECT received (%x:%x).\n",
                        (unsigned)scr_to_cpu(np->lastmsg), np->msgout[0]);
                break;

        case SIR_REJECT_SENT:
                /*-----------------------------------------------
                **
                **      We received an unknown message
                **
                **-----------------------------------------------
                */

                ncr_print_msg(cp, "MESSAGE_REJECT sent for", np->msgin);
                break;

/*--------------------------------------------------------------------
**
**      Processing of special messages
**
**--------------------------------------------------------------------
*/

        case SIR_IGN_RESIDUE:
                /*-----------------------------------------------
                **
                **      We received an IGNORE RESIDUE message,
                **      which couldn't be handled by the script.
                **
                **-----------------------------------------------
                */

                PRINT_ADDR(cp->cmd, "IGNORE_WIDE_RESIDUE received, but not yet "
                                "implemented.\n");
                break;
#if 0
        case SIR_MISSING_SAVE:
                /*-----------------------------------------------
                **
                **      We received an DISCONNECT message,
                **      but the datapointer wasn't saved before.
                **
                **-----------------------------------------------
                */

                PRINT_ADDR(cp->cmd, "DISCONNECT received, but datapointer "
                                "not saved: data=%x save=%x goal=%x.\n",
                        (unsigned) INL (nc_temp),
                        (unsigned) scr_to_cpu(np->header.savep),
                        (unsigned) scr_to_cpu(np->header.goalp));
                break;
#endif
        }

out:
        OUTONB_STD ();
}

/*==========================================================
**
**
**      Acquire a control block
**
**
**==========================================================
*/

static struct ccb *ncr_get_ccb(struct ncb *np, struct scsi_cmnd *cmd)
{
        u_char tn = cmd->device->id;
        u_char ln = cmd->device->lun;
        struct tcb *tp = &np->target[tn];
        struct lcb *lp = tp->lp[ln];
        u_char tag = NO_TAG;
        struct ccb *cp = NULL;

        /*
        **      Lun structure available ?
        */
        if (lp) {
                struct list_head *qp;
                /*
                **      Keep from using more tags than we can handle.
                */
                if (lp->usetags && lp->busyccbs >= lp->maxnxs)
                        return NULL;

                /*
                **      Allocate a new CCB if needed.
                */
                if (list_empty(&lp->free_ccbq))
                        ncr_alloc_ccb(np, tn, ln);

                /*
                **      Look for free CCB
                */
                qp = ncr_list_pop(&lp->free_ccbq);
                if (qp) {
                        cp = list_entry(qp, struct ccb, link_ccbq);
                        if (cp->magic) {
                                PRINT_ADDR(cmd, "ccb free list corrupted "
                                                "(@%p)\n", cp);
                                cp = NULL;
                        } else {
                                list_add_tail(qp, &lp->wait_ccbq);
                                ++lp->busyccbs;
                        }
                }

                /*
                **      If a CCB is available,
                **      Get a tag for this nexus if required.
                */
                if (cp) {
                        if (lp->usetags)
                                tag = lp->cb_tags[lp->ia_tag];
                }
                else if (lp->actccbs > 0)
                        return NULL;
        }

        /*
        **      if nothing available, take the default.
        */
        if (!cp)
                cp = np->ccb;

        /*
        **      Wait until available.
        */
#if 0
        while (cp->magic) {
                if (flags & SCSI_NOSLEEP) break;
                if (tsleep ((caddr_t)cp, PRIBIO|PCATCH, "ncr", 0))
                        break;
        }
#endif

        if (cp->magic)
                return NULL;

        cp->magic = 1;

        /*
        **      Move to next available tag if tag used.
        */
        if (lp) {
                if (tag != NO_TAG) {
                        ++lp->ia_tag;
                        if (lp->ia_tag == MAX_TAGS)
                                lp->ia_tag = 0;
                        lp->tags_umap |= (((tagmap_t) 1) << tag);
                }
        }

        /*
        **      Remember all informations needed to free this CCB.
        */
        cp->tag    = tag;
        cp->target = tn;
        cp->lun    = ln;

        if (DEBUG_FLAGS & DEBUG_TAGS) {
                PRINT_ADDR(cmd, "ccb @%p using tag %d.\n", cp, tag);
        }

        return cp;
}

/*==========================================================
**
**
**      Release one control block
**
**
**==========================================================
*/

static void ncr_free_ccb (struct ncb *np, struct ccb *cp)
{
        struct tcb *tp = &np->target[cp->target];
        struct lcb *lp = tp->lp[cp->lun];

        if (DEBUG_FLAGS & DEBUG_TAGS) {
                PRINT_ADDR(cp->cmd, "ccb @%p freeing tag %d.\n", cp, cp->tag);
        }

        /*
        **      If lun control block available,
        **      decrement active commands and increment credit, 
        **      free the tag if any and remove the JUMP for reselect.
        */
        if (lp) {
                if (cp->tag != NO_TAG) {
                        lp->cb_tags[lp->if_tag++] = cp->tag;
                        if (lp->if_tag == MAX_TAGS)
                                lp->if_tag = 0;
                        lp->tags_umap &= ~(((tagmap_t) 1) << cp->tag);
                        lp->tags_smap &= lp->tags_umap;
                        lp->jump_ccb[cp->tag] =
                                cpu_to_scr(NCB_SCRIPTH_PHYS(np, bad_i_t_l_q));
                } else {
                        lp->jump_ccb[0] =
                                cpu_to_scr(NCB_SCRIPTH_PHYS(np, bad_i_t_l));
                }
        }

        /*
        **      Make this CCB available.
        */

        if (lp) {
                if (cp != np->ccb)
                        list_move(&cp->link_ccbq, &lp->free_ccbq);
                --lp->busyccbs;
                if (cp->queued) {
                        --lp->queuedccbs;
                }
        }
        cp -> host_status = HS_IDLE;
        cp -> magic = 0;
        if (cp->queued) {
                --np->queuedccbs;
                cp->queued = 0;
        }

#if 0
        if (cp == np->ccb)
                wakeup ((caddr_t) cp);
#endif
}


#define ncr_reg_bus_addr(r) (np->paddr + offsetof (struct ncr_reg, r))

/*------------------------------------------------------------------------
**      Initialize the fixed part of a CCB structure.
**------------------------------------------------------------------------
**------------------------------------------------------------------------
*/
static void ncr_init_ccb(struct ncb *np, struct ccb *cp)
{
        ncrcmd copy_4 = np->features & FE_PFEN ? SCR_COPY(4) : SCR_COPY_F(4);

        /*
        **      Remember virtual and bus address of this ccb.
        */
        cp->p_ccb          = vtobus(cp);
        cp->phys.header.cp = cp;

        /*
        **      This allows list_del to work for the default ccb.
        */
        INIT_LIST_HEAD(&cp->link_ccbq);

        /*
        **      Initialyze the start and restart launch script.
        **
        **      COPY(4) @(...p_phys), @(dsa)
        **      JUMP @(sched_point)
        */
        cp->start.setup_dsa[0]   = cpu_to_scr(copy_4);
        cp->start.setup_dsa[1]   = cpu_to_scr(CCB_PHYS(cp, start.p_phys));
        cp->start.setup_dsa[2]   = cpu_to_scr(ncr_reg_bus_addr(nc_dsa));
        cp->start.schedule.l_cmd = cpu_to_scr(SCR_JUMP);
        cp->start.p_phys         = cpu_to_scr(CCB_PHYS(cp, phys));

        memcpy(&cp->restart, &cp->start, sizeof(cp->restart));

        cp->start.schedule.l_paddr   = cpu_to_scr(NCB_SCRIPT_PHYS (np, idle));
        cp->restart.schedule.l_paddr = cpu_to_scr(NCB_SCRIPTH_PHYS (np, abort));
}


/*------------------------------------------------------------------------
**      Allocate a CCB and initialize its fixed part.
**------------------------------------------------------------------------
**------------------------------------------------------------------------
*/
static void ncr_alloc_ccb(struct ncb *np, u_char tn, u_char ln)
{
        struct tcb *tp = &np->target[tn];
        struct lcb *lp = tp->lp[ln];
        struct ccb *cp = NULL;

        /*
        **      Allocate memory for this CCB.
        */
        cp = m_calloc_dma(sizeof(struct ccb), "CCB");
        if (!cp)
                return;

        /*
        **      Count it and initialyze it.
        */
        lp->actccbs++;
        np->actccbs++;
        memset(cp, 0, sizeof (*cp));
        ncr_init_ccb(np, cp);

        /*
        **      Chain into wakeup list and free ccb queue and take it 
        **      into account for tagged commands.
        */
        cp->link_ccb      = np->ccb->link_ccb;
        np->ccb->link_ccb = cp;

        list_add(&cp->link_ccbq, &lp->free_ccbq);
}

/*==========================================================
**
**
**      Allocation of resources for Targets/Luns/Tags.
**
**
**==========================================================
*/


/*------------------------------------------------------------------------
**      Target control block initialisation.
**------------------------------------------------------------------------
**      This data structure is fully initialized after a SCSI command 
**      has been successfully completed for this target.
**      It contains a SCRIPT that is called on target reselection.
**------------------------------------------------------------------------
*/
static void ncr_init_tcb (struct ncb *np, u_char tn)
{
        struct tcb *tp = &np->target[tn];
        ncrcmd copy_1 = np->features & FE_PFEN ? SCR_COPY(1) : SCR_COPY_F(1);
        int th = tn & 3;
        int i;

        /*
        **      Jump to next tcb if SFBR does not match this target.
        **      JUMP  IF (SFBR != #target#), @(next tcb)
        */
        tp->jump_tcb.l_cmd   =
                cpu_to_scr((SCR_JUMP ^ IFFALSE (DATA (0x80 + tn))));
        tp->jump_tcb.l_paddr = np->jump_tcb[th].l_paddr;

        /*
        **      Load the synchronous transfer register.
        **      COPY @(tp->sval), @(sxfer)
        */
        tp->getscr[0] = cpu_to_scr(copy_1);
        tp->getscr[1] = cpu_to_scr(vtobus (&tp->sval));
#ifdef SCSI_NCR_BIG_ENDIAN
        tp->getscr[2] = cpu_to_scr(ncr_reg_bus_addr(nc_sxfer) ^ 3);
#else
        tp->getscr[2] = cpu_to_scr(ncr_reg_bus_addr(nc_sxfer));
#endif

        /*
        **      Load the timing register.
        **      COPY @(tp->wval), @(scntl3)
        */
        tp->getscr[3] = cpu_to_scr(copy_1);
        tp->getscr[4] = cpu_to_scr(vtobus (&tp->wval));
#ifdef SCSI_NCR_BIG_ENDIAN
        tp->getscr[5] = cpu_to_scr(ncr_reg_bus_addr(nc_scntl3) ^ 3);
#else
        tp->getscr[5] = cpu_to_scr(ncr_reg_bus_addr(nc_scntl3));
#endif

        /*
        **      Get the IDENTIFY message and the lun.
        **      CALL @script(resel_lun)
        */
        tp->call_lun.l_cmd   = cpu_to_scr(SCR_CALL);
        tp->call_lun.l_paddr = cpu_to_scr(NCB_SCRIPT_PHYS (np, resel_lun));

        /*
        **      Look for the lun control block of this nexus.
        **      For i = 0 to 3
        **              JUMP ^ IFTRUE (MASK (i, 3)), @(next_lcb)
        */
        for (i = 0 ; i < 4 ; i++) {
                tp->jump_lcb[i].l_cmd   =
                                cpu_to_scr((SCR_JUMP ^ IFTRUE (MASK (i, 3))));
                tp->jump_lcb[i].l_paddr =
                                cpu_to_scr(NCB_SCRIPTH_PHYS (np, bad_identify));
        }

        /*
        **      Link this target control block to the JUMP chain.
        */
        np->jump_tcb[th].l_paddr = cpu_to_scr(vtobus (&tp->jump_tcb));

        /*
        **      These assert's should be moved at driver initialisations.
        */
#ifdef SCSI_NCR_BIG_ENDIAN
        BUG_ON(((offsetof(struct ncr_reg, nc_sxfer) ^
                 offsetof(struct tcb    , sval    )) &3) != 3);
        BUG_ON(((offsetof(struct ncr_reg, nc_scntl3) ^
                 offsetof(struct tcb    , wval    )) &3) != 3);
#else
        BUG_ON(((offsetof(struct ncr_reg, nc_sxfer) ^
                 offsetof(struct tcb    , sval    )) &3) != 0);
        BUG_ON(((offsetof(struct ncr_reg, nc_scntl3) ^
                 offsetof(struct tcb    , wval    )) &3) != 0);
#endif
}


/*------------------------------------------------------------------------
**      Lun control block allocation and initialization.
**------------------------------------------------------------------------
**      This data structure is allocated and initialized after a SCSI 
**      command has been successfully completed for this target/lun.
**------------------------------------------------------------------------
*/
static struct lcb *ncr_alloc_lcb (struct ncb *np, u_char tn, u_char ln)
{
        struct tcb *tp = &np->target[tn];
        struct lcb *lp = tp->lp[ln];
        ncrcmd copy_4 = np->features & FE_PFEN ? SCR_COPY(4) : SCR_COPY_F(4);
        int lh = ln & 3;

        /*
        **      Already done, return.
        */
        if (lp)
                return lp;

        /*
        **      Allocate the lcb.
        */
        lp = m_calloc_dma(sizeof(struct lcb), "LCB");
        if (!lp)
                goto fail;
        memset(lp, 0, sizeof(*lp));
        tp->lp[ln] = lp;

        /*
        **      Initialize the target control block if not yet.
        */
        if (!tp->jump_tcb.l_cmd)
                ncr_init_tcb(np, tn);

        /*
        **      Initialize the CCB queue headers.
        */
        INIT_LIST_HEAD(&lp->free_ccbq);
        INIT_LIST_HEAD(&lp->busy_ccbq);
        INIT_LIST_HEAD(&lp->wait_ccbq);
        INIT_LIST_HEAD(&lp->skip_ccbq);

        /*
        **      Set max CCBs to 1 and use the default 1 entry 
        **      jump table by default.
        */
        lp->maxnxs      = 1;
        lp->jump_ccb    = &lp->jump_ccb_0;
        lp->p_jump_ccb  = cpu_to_scr(vtobus(lp->jump_ccb));

        /*
        **      Initilialyze the reselect script:
        **
        **      Jump to next lcb if SFBR does not match this lun.
        **      Load TEMP with the CCB direct jump table bus address.
        **      Get the SIMPLE TAG message and the tag.
        **
        **      JUMP  IF (SFBR != #lun#), @(next lcb)
        **      COPY @(lp->p_jump_ccb),   @(temp)
        **      JUMP @script(resel_notag)
        */
        lp->jump_lcb.l_cmd   =
                cpu_to_scr((SCR_JUMP ^ IFFALSE (MASK (0x80+ln, 0xff))));
        lp->jump_lcb.l_paddr = tp->jump_lcb[lh].l_paddr;

        lp->load_jump_ccb[0] = cpu_to_scr(copy_4);
        lp->load_jump_ccb[1] = cpu_to_scr(vtobus (&lp->p_jump_ccb));
        lp->load_jump_ccb[2] = cpu_to_scr(ncr_reg_bus_addr(nc_temp));

        lp->jump_tag.l_cmd   = cpu_to_scr(SCR_JUMP);
        lp->jump_tag.l_paddr = cpu_to_scr(NCB_SCRIPT_PHYS (np, resel_notag));

        /*
        **      Link this lun control block to the JUMP chain.
        */
        tp->jump_lcb[lh].l_paddr = cpu_to_scr(vtobus (&lp->jump_lcb));

        /*
        **      Initialize command queuing control.
        */
        lp->busyccbs    = 1;
        lp->queuedccbs  = 1;
        lp->queuedepth  = 1;
fail:
        return lp;
}


/*------------------------------------------------------------------------
**      Lun control block setup on INQUIRY data received.
**------------------------------------------------------------------------
**      We only support WIDE, SYNC for targets and CMDQ for logical units.
**      This setup is done on each INQUIRY since we are expecting user 
**      will play with CHANGE DEFINITION commands. :-)
**------------------------------------------------------------------------
*/
static struct lcb *ncr_setup_lcb (struct ncb *np, struct scsi_device *sdev)
{
        unsigned char tn = sdev->id, ln = sdev->lun;
        struct tcb *tp = &np->target[tn];
        struct lcb *lp = tp->lp[ln];

        /* If no lcb, try to allocate it.  */
        if (!lp && !(lp = ncr_alloc_lcb(np, tn, ln)))
                goto fail;

        /*
        **      If unit supports tagged commands, allocate the 
        **      CCB JUMP table if not yet.
        */
        if (sdev->tagged_supported && lp->jump_ccb == &lp->jump_ccb_0) {
                int i;
                lp->jump_ccb = m_calloc_dma(256, "JUMP_CCB");
                if (!lp->jump_ccb) {
                        lp->jump_ccb = &lp->jump_ccb_0;
                        goto fail;
                }
                lp->p_jump_ccb = cpu_to_scr(vtobus(lp->jump_ccb));
                for (i = 0 ; i < 64 ; i++)
                        lp->jump_ccb[i] =
                                cpu_to_scr(NCB_SCRIPTH_PHYS (np, bad_i_t_l_q));
                for (i = 0 ; i < MAX_TAGS ; i++)
                        lp->cb_tags[i] = i;
                lp->maxnxs = MAX_TAGS;
                lp->tags_stime = jiffies + 3*HZ;
                ncr_setup_tags (np, sdev);
        }


fail:
        return lp;
}

/*==========================================================
**
**
**      Build Scatter Gather Block
**
**
**==========================================================
**
**      The transfer area may be scattered among
**      several non adjacent physical pages.
**
**      We may use MAX_SCATTER blocks.
**
**----------------------------------------------------------
*/

/*
**      We try to reduce the number of interrupts caused
**      by unexpected phase changes due to disconnects.
**      A typical harddisk may disconnect before ANY block.
**      If we wanted to avoid unexpected phase changes at all
**      we had to use a break point every 512 bytes.
**      Of course the number of scatter/gather blocks is
**      limited.
**      Under Linux, the scatter/gatter blocks are provided by 
**      the generic driver. We just have to copy addresses and 
**      sizes to the data segment array.
*/

static int ncr_scatter(struct ncb *np, struct ccb *cp, struct scsi_cmnd *cmd)
{
        int segment     = 0;
        int use_sg      = scsi_sg_count(cmd);

        cp->data_len    = 0;

        use_sg = map_scsi_sg_data(np, cmd);
        if (use_sg > 0) {
                struct scatterlist *sg;
                struct scr_tblmove *data;

                if (use_sg > MAX_SCATTER) {
                        unmap_scsi_data(np, cmd);
                        return -1;
                }

                data = &cp->phys.data[MAX_SCATTER - use_sg];

                scsi_for_each_sg(cmd, sg, use_sg, segment) {
                        dma_addr_t baddr = sg_dma_address(sg);
                        unsigned int len = sg_dma_len(sg);

                        ncr_build_sge(np, &data[segment], baddr, len);
                        cp->data_len += len;
                }
        } else
                segment = -2;

        return segment;
}

/*==========================================================
**
**
**      Test the bus snoop logic :-(
**
**      Has to be called with interrupts disabled.
**
**
**==========================================================
*/

static int __init ncr_regtest (struct ncb* np)
{
        register volatile u32 data;
        /*
        **      ncr registers may NOT be cached.
        **      write 0xffffffff to a read only register area,
        **      and try to read it back.
        */
        data = 0xffffffff;
        OUTL_OFF(offsetof(struct ncr_reg, nc_dstat), data);
        data = INL_OFF(offsetof(struct ncr_reg, nc_dstat));
#if 1
        if (data == 0xffffffff) {
#else
        if ((data & 0xe2f0fffd) != 0x02000080) {
#endif
                printk ("CACHE TEST FAILED: reg dstat-sstat2 readback %x.\n",
                        (unsigned) data);
                return (0x10);
        }
        return (0);
}

static int __init ncr_snooptest (struct ncb* np)
{
        u32     ncr_rd, ncr_wr, ncr_bk, host_rd, host_wr, pc;
        int     i, err=0;
        if (np->reg) {
                err |= ncr_regtest (np);
                if (err)
                        return (err);
        }

        /* init */
        pc  = NCB_SCRIPTH_PHYS (np, snooptest);
        host_wr = 1;
        ncr_wr  = 2;
        /*
        **      Set memory and register.
        */
        np->ncr_cache = cpu_to_scr(host_wr);
        OUTL (nc_temp, ncr_wr);
        /*
        **      Start script (exchange values)
        */
        OUTL_DSP (pc);
        /*
        **      Wait 'til done (with timeout)
        */
        for (i=0; i<NCR_SNOOP_TIMEOUT; i++)
                if (INB(nc_istat) & (INTF|SIP|DIP))
                        break;
        /*
        **      Save termination position.
        */
        pc = INL (nc_dsp);
        /*
        **      Read memory and register.
        */
        host_rd = scr_to_cpu(np->ncr_cache);
        ncr_rd  = INL (nc_scratcha);
        ncr_bk  = INL (nc_temp);
        /*
        **      Reset ncr chip
        */
        ncr_chip_reset(np, 100);
        /*
        **      check for timeout
        */
        if (i>=NCR_SNOOP_TIMEOUT) {
                printk ("CACHE TEST FAILED: timeout.\n");
                return (0x20);
        }
        /*
        **      Check termination position.
        */
        if (pc != NCB_SCRIPTH_PHYS (np, snoopend)+8) {
                printk ("CACHE TEST FAILED: script execution failed.\n");
                printk ("start=%08lx, pc=%08lx, end=%08lx\n", 
                        (u_long) NCB_SCRIPTH_PHYS (np, snooptest), (u_long) pc,
                        (u_long) NCB_SCRIPTH_PHYS (np, snoopend) +8);
                return (0x40);
        }
        /*
        **      Show results.
        */
        if (host_wr != ncr_rd) {
                printk ("CACHE TEST FAILED: host wrote %d, ncr read %d.\n",
                        (int) host_wr, (int) ncr_rd);
                err |= 1;
        }
        if (host_rd != ncr_wr) {
                printk ("CACHE TEST FAILED: ncr wrote %d, host read %d.\n",
                        (int) ncr_wr, (int) host_rd);
                err |= 2;
        }
        if (ncr_bk != ncr_wr) {
                printk ("CACHE TEST FAILED: ncr wrote %d, read back %d.\n",
                        (int) ncr_wr, (int) ncr_bk);
                err |= 4;
        }
        return (err);
}

/*==========================================================
**
**      Determine the ncr's clock frequency.
**      This is essential for the negotiation
**      of the synchronous transfer rate.
**
**==========================================================
**
**      Note: we have to return the correct value.
**      THERE IS NO SAFE DEFAULT VALUE.
**
**      Most NCR/SYMBIOS boards are delivered with a 40 Mhz clock.
**      53C860 and 53C875 rev. 1 support fast20 transfers but 
**      do not have a clock doubler and so are provided with a 
**      80 MHz clock. All other fast20 boards incorporate a doubler 
**      and so should be delivered with a 40 MHz clock.
**      The future fast40 chips (895/895) use a 40 Mhz base clock 
**      and provide a clock quadrupler (160 Mhz). The code below 
**      tries to deal as cleverly as possible with all this stuff.
**
**----------------------------------------------------------
*/

/*
 *      Select NCR SCSI clock frequency
 */
static void ncr_selectclock(struct ncb *np, u_char scntl3)
{
        if (np->multiplier < 2) {
                OUTB(nc_scntl3, scntl3);
                return;
        }

        if (bootverbose >= 2)
                printk ("%s: enabling clock multiplier\n", ncr_name(np));

        OUTB(nc_stest1, DBLEN);    /* Enable clock multiplier             */
        if (np->multiplier > 2) {  /* Poll bit 5 of stest4 for quadrupler */
                int i = 20;
                while (!(INB(nc_stest4) & LCKFRQ) && --i > 0)
                        udelay(20);
                if (!i)
                        printk("%s: the chip cannot lock the frequency\n", ncr_name(np));
        } else                  /* Wait 20 micro-seconds for doubler    */
                udelay(20);
        OUTB(nc_stest3, HSC);           /* Halt the scsi clock          */
        OUTB(nc_scntl3, scntl3);
        OUTB(nc_stest1, (DBLEN|DBLSEL));/* Select clock multiplier      */
        OUTB(nc_stest3, 0x00);          /* Restart scsi clock           */
}


/*
 *      calculate NCR SCSI clock frequency (in KHz)
 */
static unsigned __init ncrgetfreq (struct ncb *np, int gen)
{
        unsigned ms = 0;
        char count = 0;

        /*
         * Measure GEN timer delay in order 
         * to calculate SCSI clock frequency
         *
         * This code will never execute too
         * many loop iterations (if DELAY is 
         * reasonably correct). It could get
         * too low a delay (too high a freq.)
         * if the CPU is slow executing the 
         * loop for some reason (an NMI, for
         * example). For this reason we will
         * if multiple measurements are to be 
         * performed trust the higher delay 
         * (lower frequency returned).
         */
        OUTB (nc_stest1, 0);    /* make sure clock doubler is OFF */
        OUTW (nc_sien , 0);     /* mask all scsi interrupts */
        (void) INW (nc_sist);   /* clear pending scsi interrupt */
        OUTB (nc_dien , 0);     /* mask all dma interrupts */
        (void) INW (nc_sist);   /* another one, just to be sure :) */
        OUTB (nc_scntl3, 4);    /* set pre-scaler to divide by 3 */
        OUTB (nc_stime1, 0);    /* disable general purpose timer */
        OUTB (nc_stime1, gen);  /* set to nominal delay of 1<<gen * 125us */
        while (!(INW(nc_sist) & GEN) && ms++ < 100000) {
                for (count = 0; count < 10; count ++)
                        udelay(100);    /* count ms */
        }
        OUTB (nc_stime1, 0);    /* disable general purpose timer */
        /*
         * set prescaler to divide by whatever 0 means
         * 0 ought to choose divide by 2, but appears
         * to set divide by 3.5 mode in my 53c810 ...
         */
        OUTB (nc_scntl3, 0);

        if (bootverbose >= 2)
                printk ("%s: Delay (GEN=%d): %u msec\n", ncr_name(np), gen, ms);
        /*
         * adjust for prescaler, and convert into KHz 
         */
        return ms ? ((1 << gen) * 4340) / ms : 0;
}

/*
 *      Get/probe NCR SCSI clock frequency
 */
static void __init ncr_getclock (struct ncb *np, int mult)
{
        unsigned char scntl3 = INB(nc_scntl3);
        unsigned char stest1 = INB(nc_stest1);
        unsigned f1;

        np->multiplier = 1;
        f1 = 40000;

        /*
        **      True with 875 or 895 with clock multiplier selected
        */
        if (mult > 1 && (stest1 & (DBLEN+DBLSEL)) == DBLEN+DBLSEL) {
                if (bootverbose >= 2)
                        printk ("%s: clock multiplier found\n", ncr_name(np));
                np->multiplier = mult;
        }

        /*
        **      If multiplier not found or scntl3 not 7,5,3,
        **      reset chip and get frequency from general purpose timer.
        **      Otherwise trust scntl3 BIOS setting.
        */
        if (np->multiplier != mult || (scntl3 & 7) < 3 || !(scntl3 & 1)) {
                unsigned f2;

                ncr_chip_reset(np, 5);

                (void) ncrgetfreq (np, 11);     /* throw away first result */
                f1 = ncrgetfreq (np, 11);
                f2 = ncrgetfreq (np, 11);

                if(bootverbose)
                        printk ("%s: NCR clock is %uKHz, %uKHz\n", ncr_name(np), f1, f2);

                if (f1 > f2) f1 = f2;           /* trust lower result   */

                if      (f1 <   45000)          f1 =  40000;
                else if (f1 <   55000)          f1 =  50000;
                else                            f1 =  80000;

                if (f1 < 80000 && mult > 1) {
                        if (bootverbose >= 2)
                                printk ("%s: clock multiplier assumed\n", ncr_name(np));
                        np->multiplier  = mult;
                }
        } else {
                if      ((scntl3 & 7) == 3)     f1 =  40000;
                else if ((scntl3 & 7) == 5)     f1 =  80000;
                else                            f1 = 160000;

                f1 /= np->multiplier;
        }

        /*
        **      Compute controller synchronous parameters.
        */
        f1              *= np->multiplier;
        np->clock_khz   = f1;
}

/*===================== LINUX ENTRY POINTS SECTION ==========================*/

static int ncr53c8xx_sdev_init(struct scsi_device *device)
{
        struct Scsi_Host *host = device->host;
        struct ncb *np = ((struct host_data *) host->hostdata)->ncb;
        struct tcb *tp = &np->target[device->id];
        tp->starget = device->sdev_target;

        return 0;
}

static int ncr53c8xx_sdev_configure(struct scsi_device *device,
                                    struct queue_limits *lim)
{
        struct Scsi_Host *host = device->host;
        struct ncb *np = ((struct host_data *) host->hostdata)->ncb;
        struct tcb *tp = &np->target[device->id];
        struct lcb *lp = tp->lp[device->lun];
        int numtags, depth_to_use;

        ncr_setup_lcb(np, device);

        /*
        **      Select queue depth from driver setup.
        **      Donnot use more than configured by user.
        **      Use at least 2.
        **      Donnot use more than our maximum.
        */
        numtags = device_queue_depth(np->unit, device->id, device->lun);
        if (numtags > tp->usrtags)
                numtags = tp->usrtags;
        if (!device->tagged_supported)
                numtags = 1;
        depth_to_use = numtags;
        if (depth_to_use < 2)
                depth_to_use = 2;
        if (depth_to_use > MAX_TAGS)
                depth_to_use = MAX_TAGS;

        scsi_change_queue_depth(device, depth_to_use);

        /*
        **      Since the queue depth is not tunable under Linux,
        **      we need to know this value in order not to 
        **      announce stupid things to user.
        **
        **      XXX(hch): As of Linux 2.6 it certainly _is_ tunable..
        **                In fact we just tuned it, or did I miss
        **                something important? :)
        */
        if (lp) {
                lp->numtags = lp->maxtags = numtags;
                lp->scdev_depth = depth_to_use;
        }
        ncr_setup_tags (np, device);

#ifdef DEBUG_NCR53C8XX
        printk("ncr53c8xx_select_queue_depth: host=%d, id=%d, lun=%d, depth=%d\n",
               np->unit, device->id, device->lun, depth_to_use);
#endif

        if (spi_support_sync(device->sdev_target) &&
            !spi_initial_dv(device->sdev_target))
                spi_dv_device(device);
        return 0;
}

static enum scsi_qc_status ncr53c8xx_queue_command_lck(struct scsi_cmnd *cmd)
{
     struct ncr_cmd_priv *cmd_priv = scsi_cmd_priv(cmd);
     void (*done)(struct scsi_cmnd *) = scsi_done;
     struct ncb *np = ((struct host_data *) cmd->device->host->hostdata)->ncb;
     unsigned long flags;
     int sts;

#ifdef DEBUG_NCR53C8XX
printk("ncr53c8xx_queue_command\n");
#endif

     cmd->host_scribble = NULL;
     cmd_priv->data_mapped = 0;
     cmd_priv->data_mapping = 0;

     spin_lock_irqsave(&np->smp_lock, flags);

     if ((sts = ncr_queue_command(np, cmd)) != DID_OK) {
             set_host_byte(cmd, sts);
#ifdef DEBUG_NCR53C8XX
printk("ncr53c8xx : command not queued - result=%d\n", sts);
#endif
     }
#ifdef DEBUG_NCR53C8XX
     else
printk("ncr53c8xx : command successfully queued\n");
#endif

     spin_unlock_irqrestore(&np->smp_lock, flags);

     if (sts != DID_OK) {
          unmap_scsi_data(np, cmd);
          done(cmd);
          sts = 0;
     }

     return sts;
}

static DEF_SCSI_QCMD(ncr53c8xx_queue_command)

irqreturn_t ncr53c8xx_intr(int irq, void *dev_id)
{
     unsigned long flags;
     struct Scsi_Host *shost = (struct Scsi_Host *)dev_id;
     struct host_data *host_data = (struct host_data *)shost->hostdata;
     struct ncb *np = host_data->ncb;
     struct scsi_cmnd *done_list;

#ifdef DEBUG_NCR53C8XX
     printk("ncr53c8xx : interrupt received\n");
#endif

     if (DEBUG_FLAGS & DEBUG_TINY) printk ("[");

     spin_lock_irqsave(&np->smp_lock, flags);
     ncr_exception(np);
     done_list     = np->done_list;
     np->done_list = NULL;
     spin_unlock_irqrestore(&np->smp_lock, flags);

     if (DEBUG_FLAGS & DEBUG_TINY) printk ("]\n");

     if (done_list)
             ncr_flush_done_cmds(done_list);
     return IRQ_HANDLED;
}

static void ncr53c8xx_timeout(struct timer_list *t)
{
        struct ncb *np = timer_container_of(np, t, timer);
        unsigned long flags;
        struct scsi_cmnd *done_list;

        spin_lock_irqsave(&np->smp_lock, flags);
        ncr_timeout(np);
        done_list     = np->done_list;
        np->done_list = NULL;
        spin_unlock_irqrestore(&np->smp_lock, flags);

        if (done_list)
                ncr_flush_done_cmds(done_list);
}

static int ncr53c8xx_bus_reset(struct scsi_cmnd *cmd)
{
        struct ncb *np = ((struct host_data *) cmd->device->host->hostdata)->ncb;
        int sts;
        unsigned long flags;
        struct scsi_cmnd *done_list;

        /*
         * If the mid-level driver told us reset is synchronous, it seems 
         * that we must call the done() callback for the involved command, 
         * even if this command was not queued to the low-level driver, 
         * before returning SUCCESS.
         */

        spin_lock_irqsave(&np->smp_lock, flags);
        sts = ncr_reset_bus(np);

        done_list     = np->done_list;
        np->done_list = NULL;
        spin_unlock_irqrestore(&np->smp_lock, flags);

        ncr_flush_done_cmds(done_list);

        return sts;
}


/*
**      Scsi command waiting list management.
**
**      It may happen that we cannot insert a scsi command into the start queue,
**      in the following circumstances.
**              Too few preallocated ccb(s), 
**              maxtags < cmd_per_lun of the Linux host control block,
**              etc...
**      Such scsi commands are inserted into a waiting list.
**      When a scsi command complete, we try to requeue the commands of the
**      waiting list.
*/

#define next_wcmd host_scribble

static void insert_into_waiting_list(struct ncb *np, struct scsi_cmnd *cmd)
{
        struct scsi_cmnd *wcmd;

#ifdef DEBUG_WAITING_LIST
        printk("%s: cmd %lx inserted into waiting list\n", ncr_name(np), (u_long) cmd);
#endif
        cmd->next_wcmd = NULL;
        if (!(wcmd = np->waiting_list)) np->waiting_list = cmd;
        else {
                while (wcmd->next_wcmd)
                        wcmd = (struct scsi_cmnd *) wcmd->next_wcmd;
                wcmd->next_wcmd = (char *) cmd;
        }
}

static void process_waiting_list(struct ncb *np, int sts)
{
        struct scsi_cmnd *waiting_list, *wcmd;

        waiting_list = np->waiting_list;
        np->waiting_list = NULL;

#ifdef DEBUG_WAITING_LIST
        if (waiting_list) printk("%s: waiting_list=%lx processing sts=%d\n", ncr_name(np), (u_long) waiting_list, sts);
#endif
        while ((wcmd = waiting_list) != NULL) {
                waiting_list = (struct scsi_cmnd *) wcmd->next_wcmd;
                wcmd->next_wcmd = NULL;
                if (sts == DID_OK) {
#ifdef DEBUG_WAITING_LIST
        printk("%s: cmd %lx trying to requeue\n", ncr_name(np), (u_long) wcmd);
#endif
                        sts = ncr_queue_command(np, wcmd);
                }
                if (sts != DID_OK) {
#ifdef DEBUG_WAITING_LIST
        printk("%s: cmd %lx done forced sts=%d\n", ncr_name(np), (u_long) wcmd, sts);
#endif
                        set_host_byte(wcmd, sts);
                        ncr_queue_done_cmd(np, wcmd);
                }
        }
}

#undef next_wcmd

static ssize_t show_ncr53c8xx_revision(struct device *dev,
                                       struct device_attribute *attr, char *buf)
{
        struct Scsi_Host *host = class_to_shost(dev);
        struct host_data *host_data = (struct host_data *)host->hostdata;
  
        return snprintf(buf, 20, "0x%x\n", host_data->ncb->revision_id);
}
  
static struct device_attribute ncr53c8xx_revision_attr = {
        .attr   = { .name = "revision", .mode = S_IRUGO, },
        .show   = show_ncr53c8xx_revision,
};
  
static struct attribute *ncr53c8xx_host_attrs[] = {
        &ncr53c8xx_revision_attr.attr,
        NULL
};

ATTRIBUTE_GROUPS(ncr53c8xx_host);

/*==========================================================
**
**      Boot command line.
**
**==========================================================
*/
#ifdef  MODULE
char *ncr53c8xx;        /* command line passed by insmod */
module_param(ncr53c8xx, charp, 0);
#endif

#ifndef MODULE
static int __init ncr53c8xx_setup(char *str)
{
        return sym53c8xx__setup(str);
}

__setup("ncr53c8xx=", ncr53c8xx_setup);
#endif


/*
 *      Host attach and initialisations.
 *
 *      Allocate host data and ncb structure.
 *      Request IO region and remap MMIO region.
 *      Do chip initialization.
 *      If all is OK, install interrupt handling and
 *      start the timer daemon.
 */
struct Scsi_Host * __init ncr_attach(struct scsi_host_template *tpnt,
                                        int unit, struct ncr_device *device)
{
        struct host_data *host_data;
        struct ncb *np = NULL;
        struct Scsi_Host *instance = NULL;
        u_long flags = 0;
        int i;

        WARN_ON_ONCE(tpnt->cmd_size < sizeof(struct ncr_cmd_priv));

        if (!tpnt->name)
                tpnt->name      = SCSI_NCR_DRIVER_NAME;
        if (!tpnt->shost_groups)
                tpnt->shost_groups = ncr53c8xx_host_groups;

        tpnt->queuecommand      = ncr53c8xx_queue_command;
        tpnt->sdev_configure    = ncr53c8xx_sdev_configure;
        tpnt->sdev_init         = ncr53c8xx_sdev_init;
        tpnt->eh_bus_reset_handler = ncr53c8xx_bus_reset;
        tpnt->can_queue         = SCSI_NCR_CAN_QUEUE;
        tpnt->this_id           = 7;
        tpnt->sg_tablesize      = SCSI_NCR_SG_TABLESIZE;
        tpnt->cmd_per_lun       = SCSI_NCR_CMD_PER_LUN;

        if (device->differential)
                driver_setup.diff_support = device->differential;

        printk(KERN_INFO "ncr53c720-%d: rev 0x%x irq %d\n",
                unit, device->chip.revision_id, device->slot.irq);

        instance = scsi_host_alloc(tpnt, sizeof(*host_data));
        if (!instance)
                goto attach_error;
        host_data = (struct host_data *) instance->hostdata;

        np = __m_calloc_dma(device->dev, sizeof(struct ncb), "NCB");
        if (!np)
                goto attach_error;
        spin_lock_init(&np->smp_lock);
        np->dev = device->dev;
        np->p_ncb = vtobus(np);
        host_data->ncb = np;

        np->ccb = m_calloc_dma(sizeof(struct ccb), "CCB");
        if (!np->ccb)
                goto attach_error;

        /* Store input information in the host data structure.  */
        np->unit        = unit;
        np->verbose     = driver_setup.verbose;
        sprintf(np->inst_name, "ncr53c720-%d", np->unit);
        np->revision_id = device->chip.revision_id;
        np->features    = device->chip.features;
        np->clock_divn  = device->chip.nr_divisor;
        np->maxoffs     = device->chip.offset_max;
        np->maxburst    = device->chip.burst_max;
        np->myaddr      = device->host_id;

        /* Allocate SCRIPTS areas.  */
        np->script0 = m_calloc_dma(sizeof(struct script), "SCRIPT");
        if (!np->script0)
                goto attach_error;
        np->scripth0 = m_calloc_dma(sizeof(struct scripth), "SCRIPTH");
        if (!np->scripth0)
                goto attach_error;

        timer_setup(&np->timer, ncr53c8xx_timeout, 0);

        /* Try to map the controller chip to virtual and physical memory. */

        np->paddr       = device->slot.base;
        np->paddr2      = (np->features & FE_RAM) ? device->slot.base_2 : 0;

        if (device->slot.base_v)
                np->vaddr = device->slot.base_v;
        else
                np->vaddr = ioremap(device->slot.base_c, 128);

        if (!np->vaddr) {
                printk(KERN_ERR
                        "%s: can't map memory mapped IO region\n",ncr_name(np));
                goto attach_error;
        } else {
                if (bootverbose > 1)
                        printk(KERN_INFO
                                "%s: using memory mapped IO at virtual address 0x%lx\n", ncr_name(np), (u_long) np->vaddr);
        }

        /* Make the controller's registers available.  Now the INB INW INL
         * OUTB OUTW OUTL macros can be used safely.
         */

        np->reg = (struct ncr_reg __iomem *)np->vaddr;

        /* Do chip dependent initialization.  */
        ncr_prepare_setting(np);

        if (np->paddr2 && sizeof(struct script) > 4096) {
                np->paddr2 = 0;
                printk(KERN_WARNING "%s: script too large, NOT using on chip RAM.\n",
                        ncr_name(np));
        }

        instance->max_channel   = 0;
        instance->this_id       = np->myaddr;
        instance->max_id        = np->maxwide ? 16 : 8;
        instance->max_lun       = SCSI_NCR_MAX_LUN;
        instance->base          = (unsigned long) np->reg;
        instance->irq           = device->slot.irq;
        instance->unique_id     = device->slot.base;
        instance->dma_channel   = 0;
        instance->cmd_per_lun   = MAX_TAGS;
        instance->can_queue     = (MAX_START-4);
        /* This can happen if you forget to call ncr53c8xx_init from
         * your module_init */
        BUG_ON(!ncr53c8xx_transport_template);
        instance->transportt    = ncr53c8xx_transport_template;

        /* Patch script to physical addresses */
        ncr_script_fill(&script0, &scripth0);

        np->scripth     = np->scripth0;
        np->p_scripth   = vtobus(np->scripth);
        np->p_script    = (np->paddr2) ?  np->paddr2 : vtobus(np->script0);

        ncr_script_copy_and_bind(np, (ncrcmd *) &script0,
                        (ncrcmd *) np->script0, sizeof(struct script));
        ncr_script_copy_and_bind(np, (ncrcmd *) &scripth0,
                        (ncrcmd *) np->scripth0, sizeof(struct scripth));
        np->ccb->p_ccb  = vtobus (np->ccb);

        /* Patch the script for LED support.  */

        if (np->features & FE_LED0) {
                np->script0->idle[0]  =
                                cpu_to_scr(SCR_REG_REG(gpreg, SCR_OR,  0x01));
                np->script0->reselected[0] =
                                cpu_to_scr(SCR_REG_REG(gpreg, SCR_AND, 0xfe));
                np->script0->start[0] =
                                cpu_to_scr(SCR_REG_REG(gpreg, SCR_AND, 0xfe));
        }

        /*
         * Look for the target control block of this nexus.
         * For i = 0 to 3
         *   JUMP ^ IFTRUE (MASK (i, 3)), @(next_lcb)
         */
        for (i = 0 ; i < 4 ; i++) {
                np->jump_tcb[i].l_cmd   =
                                cpu_to_scr((SCR_JUMP ^ IFTRUE (MASK (i, 3))));
                np->jump_tcb[i].l_paddr =
                                cpu_to_scr(NCB_SCRIPTH_PHYS (np, bad_target));
        }

        ncr_chip_reset(np, 100);

        /* Now check the cache handling of the chipset.  */

        if (ncr_snooptest(np)) {
                printk(KERN_ERR "CACHE INCORRECTLY CONFIGURED.\n");
                goto attach_error;
        }

        /* Install the interrupt handler.  */
        np->irq = device->slot.irq;

        /* Initialize the fixed part of the default ccb.  */
        ncr_init_ccb(np, np->ccb);

        /*
         * After SCSI devices have been opened, we cannot reset the bus
         * safely, so we do it here.  Interrupt handler does the real work.
         * Process the reset exception if interrupts are not enabled yet.
         * Then enable disconnects.
         */
        spin_lock_irqsave(&np->smp_lock, flags);
        if (ncr_reset_scsi_bus(np, 0, driver_setup.settle_delay) != 0) {
                printk(KERN_ERR "%s: FATAL ERROR: CHECK SCSI BUS - CABLES, TERMINATION, DEVICE POWER etc.!\n", ncr_name(np));

                spin_unlock_irqrestore(&np->smp_lock, flags);
                goto attach_error;
        }
        ncr_exception(np);

        np->disc = 1;

        /*
         * The middle-level SCSI driver does not wait for devices to settle.
         * Wait synchronously if more than 2 seconds.
         */
        if (driver_setup.settle_delay > 2) {
                printk(KERN_INFO "%s: waiting %d seconds for scsi devices to settle...\n",
                        ncr_name(np), driver_setup.settle_delay);
                mdelay(1000 * driver_setup.settle_delay);
        }

        /* start the timeout daemon */
        np->lasttime=0;
        ncr_timeout (np);

        /* use SIMPLE TAG messages by default */
#ifdef SCSI_NCR_ALWAYS_SIMPLE_TAG
        np->order = SIMPLE_QUEUE_TAG;
#endif

        spin_unlock_irqrestore(&np->smp_lock, flags);

        return instance;

 attach_error:
        if (!instance)
                return NULL;
        printk(KERN_INFO "%s: detaching...\n", ncr_name(np));
        if (!np)
                goto unregister;
        if (np->scripth0)
                m_free_dma(np->scripth0, sizeof(struct scripth), "SCRIPTH");
        if (np->script0)
                m_free_dma(np->script0, sizeof(struct script), "SCRIPT");
        if (np->ccb)
                m_free_dma(np->ccb, sizeof(struct ccb), "CCB");
        m_free_dma(np, sizeof(struct ncb), "NCB");
        host_data->ncb = NULL;

 unregister:
        scsi_host_put(instance);

        return NULL;
}


void ncr53c8xx_release(struct Scsi_Host *host)
{
        struct host_data *host_data = shost_priv(host);
#ifdef DEBUG_NCR53C8XX
        printk("ncr53c8xx: release\n");
#endif
        if (host_data->ncb)
                ncr_detach(host_data->ncb);
        scsi_host_put(host);
}

static void ncr53c8xx_set_period(struct scsi_target *starget, int period)
{
        struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
        struct ncb *np = ((struct host_data *)shost->hostdata)->ncb;
        struct tcb *tp = &np->target[starget->id];

        if (period > np->maxsync)
                period = np->maxsync;
        else if (period < np->minsync)
                period = np->minsync;

        tp->usrsync = period;

        ncr_negotiate(np, tp);
}

static void ncr53c8xx_set_offset(struct scsi_target *starget, int offset)
{
        struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
        struct ncb *np = ((struct host_data *)shost->hostdata)->ncb;
        struct tcb *tp = &np->target[starget->id];

        if (offset > np->maxoffs)
                offset = np->maxoffs;
        else if (offset < 0)
                offset = 0;

        tp->maxoffs = offset;

        ncr_negotiate(np, tp);
}

static void ncr53c8xx_set_width(struct scsi_target *starget, int width)
{
        struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
        struct ncb *np = ((struct host_data *)shost->hostdata)->ncb;
        struct tcb *tp = &np->target[starget->id];

        if (width > np->maxwide)
                width = np->maxwide;
        else if (width < 0)
                width = 0;

        tp->usrwide = width;

        ncr_negotiate(np, tp);
}

static void ncr53c8xx_get_signalling(struct Scsi_Host *shost)
{
        struct ncb *np = ((struct host_data *)shost->hostdata)->ncb;
        enum spi_signal_type type;

        switch (np->scsi_mode) {
        case SMODE_SE:
                type = SPI_SIGNAL_SE;
                break;
        case SMODE_HVD:
                type = SPI_SIGNAL_HVD;
                break;
        default:
                type = SPI_SIGNAL_UNKNOWN;
                break;
        }
        spi_signalling(shost) = type;
}

static struct spi_function_template ncr53c8xx_transport_functions =  {
        .set_period     = ncr53c8xx_set_period,
        .show_period    = 1,
        .set_offset     = ncr53c8xx_set_offset,
        .show_offset    = 1,
        .set_width      = ncr53c8xx_set_width,
        .show_width     = 1,
        .get_signalling = ncr53c8xx_get_signalling,
};

int __init ncr53c8xx_init(void)
{
        ncr53c8xx_transport_template = spi_attach_transport(&ncr53c8xx_transport_functions);
        if (!ncr53c8xx_transport_template)
                return -ENODEV;
        return 0;
}

void ncr53c8xx_exit(void)
{
        spi_release_transport(ncr53c8xx_transport_template);
}