/*-
 * Copyright (c) 1999,2000 Michael Smith
 * Copyright (c) 2000 BSDi
 * Copyright (c) 2005 Scott Long
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
/*-
 * Copyright (c) 2002 Eric Moore
 * Copyright (c) 2002, 2004 LSI Logic Corporation
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The party using or redistributing the source code and binary forms
 *    agrees to the disclaimer below and the terms and conditions set forth
 *    herein.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $FreeBSD: src/sys/dev/amr/amr.c,v 1.99 2012/08/31 09:42:46 scottl Exp $
 */

/*
 * Driver for the AMI MegaRaid family of controllers.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/sysctl.h>
#include <sys/sysmsg.h>

#include <sys/bio.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/stat.h>

#include <machine/cpu.h>
#include <sys/rman.h>

#include <bus/pci/pcireg.h>
#include <bus/pci/pcivar.h>

#include <dev/raid/amr/amrio.h>
#include <dev/raid/amr/amrreg.h>
#include <dev/raid/amr/amrvar.h>
#define AMR_DEFINE_TABLES
#include <dev/raid/amr/amr_tables.h>

SYSCTL_NODE(_hw, OID_AUTO, amr, CTLFLAG_RD, 0, "AMR driver parameters");

static d_open_t         amr_open;
static d_close_t        amr_close;
static d_ioctl_t        amr_ioctl;

static struct dev_ops amr_ops = {
        { "amr", 0, 0 },
        .d_open =       amr_open,
        .d_close =      amr_close,
        .d_ioctl =      amr_ioctl,
};

int linux_no_adapter = 0;
/*
 * Initialisation, bus interface.
 */
static void     amr_startup(void *arg);

/*
 * Command wrappers
 */
static int      amr_query_controller(struct amr_softc *sc);
static void     *amr_enquiry(struct amr_softc *sc, size_t bufsize, 
                             u_int8_t cmd, u_int8_t cmdsub, u_int8_t cmdqual, int *status);
static void     amr_completeio(struct amr_command *ac);
static int      amr_support_ext_cdb(struct amr_softc *sc);

/*
 * Command buffer allocation.
 */
static void     amr_alloccmd_cluster(struct amr_softc *sc);
static void     amr_freecmd_cluster(struct amr_command_cluster *acc);

/*
 * Command processing.
 */
static int      amr_bio_command(struct amr_softc *sc, struct amr_command **acp);
static int      amr_wait_command(struct amr_command *ac);
static int      amr_mapcmd(struct amr_command *ac);
static void     amr_unmapcmd(struct amr_command *ac);
static int      amr_start(struct amr_command *ac);
static void     amr_complete(void *context, ac_qhead_t *head);
static void     amr_setup_sg(void *arg, bus_dma_segment_t *segs, int nsegments, int error);
static void     amr_setup_data(void *arg, bus_dma_segment_t *segs, int nsegments, int error);
static void     amr_setup_ccb(void *arg, bus_dma_segment_t *segs, int nsegments, int error);
static void     amr_abort_load(struct amr_command *ac);

/*
 * Interface-specific shims
 */
static int      amr_quartz_submit_command(struct amr_command *ac);
static int      amr_quartz_get_work(struct amr_softc *sc, struct amr_mailbox *mbsave);
static int      amr_quartz_poll_command(struct amr_command *ac);
static int      amr_quartz_poll_command1(struct amr_softc *sc, struct amr_command *ac);

static int      amr_std_submit_command(struct amr_command *ac);
static int      amr_std_get_work(struct amr_softc *sc, struct amr_mailbox *mbsave);
static int      amr_std_poll_command(struct amr_command *ac);
static void     amr_std_attach_mailbox(struct amr_softc *sc);

#ifdef AMR_BOARD_INIT
static int      amr_quartz_init(struct amr_softc *sc);
static int      amr_std_init(struct amr_softc *sc);
#endif

/*
 * Debugging
 */
static void     amr_describe_controller(struct amr_softc *sc);
#ifdef AMR_DEBUG
#if 0
static void     amr_printcommand(struct amr_command *ac);
#endif
#endif

static void     amr_init_sysctl(struct amr_softc *sc);
static int      amr_linux_ioctl_int(struct cdev *dev, u_long cmd, caddr_t addr,
                    int32_t flag, struct sysmsg *sm);

static MALLOC_DEFINE(M_AMR, "amr", "AMR memory");

/********************************************************************************
 ********************************************************************************
                                                                      Inline Glue
 ********************************************************************************
 ********************************************************************************/

/********************************************************************************
 ********************************************************************************
                                                                Public Interfaces
 ********************************************************************************
 ********************************************************************************/

/********************************************************************************
 * Initialise the controller and softc.
 */
int
amr_attach(struct amr_softc *sc)
{
    device_t child;

    debug_called(1);

    /*
     * Initialise per-controller queues.
     */
    amr_init_qhead(&sc->amr_freecmds);
    amr_init_qhead(&sc->amr_ready);
    TAILQ_INIT(&sc->amr_cmd_clusters);
    bioq_init(&sc->amr_bioq);

    debug(2, "queue init done");

    /*
     * Configure for this controller type.
     */
    if (AMR_IS_QUARTZ(sc)) {
        sc->amr_submit_command = amr_quartz_submit_command;
        sc->amr_get_work       = amr_quartz_get_work;
        sc->amr_poll_command   = amr_quartz_poll_command;
        sc->amr_poll_command1  = amr_quartz_poll_command1;
    } else {
        sc->amr_submit_command = amr_std_submit_command;
        sc->amr_get_work       = amr_std_get_work;
        sc->amr_poll_command   = amr_std_poll_command;
        amr_std_attach_mailbox(sc);
    }

#ifdef AMR_BOARD_INIT
    if ((AMR_IS_QUARTZ(sc) ? amr_quartz_init(sc) : amr_std_init(sc)))
        return(ENXIO);
#endif

    /*
     * Allocate initial commands.
     */
    amr_alloccmd_cluster(sc);

    /*
     * Quiz controller for features and limits.
     */
    if (amr_query_controller(sc))
        return(ENXIO);

    debug(2, "controller query complete");

    /*
     * preallocate the remaining commands.
     */
    while (sc->amr_nextslot < sc->amr_maxio)
        amr_alloccmd_cluster(sc);

    /*
     * Setup sysctls.
     */
    amr_init_sysctl(sc);

    /*
     * Attach our 'real' SCSI channels to CAM.
     */
    child = device_add_child(sc->amr_dev, "amrp", -1);
    sc->amr_pass = child;
    if (child != NULL) {
        device_set_softc(child, sc);
        device_set_desc(child, "SCSI Passthrough Bus");
        bus_generic_attach(sc->amr_dev);
    }

    /*
     * Create the control device.
     */
    sc->amr_dev_t = make_dev(&amr_ops, device_get_unit(sc->amr_dev), UID_ROOT, GID_OPERATOR,
                             S_IRUSR | S_IWUSR, "amr%d", device_get_unit(sc->amr_dev));
    sc->amr_dev_t->si_drv1 = sc;
    linux_no_adapter++;
    if (device_get_unit(sc->amr_dev) == 0)
        make_dev_alias(sc->amr_dev_t, "megadev0");

    /*
     * Schedule ourselves to bring the controller up once interrupts are
     * available.
     */
    bzero(&sc->amr_ich, sizeof(struct intr_config_hook));
    sc->amr_ich.ich_func = amr_startup;
    sc->amr_ich.ich_arg = sc;
    sc->amr_ich.ich_desc = "amr";
    if (config_intrhook_establish(&sc->amr_ich) != 0) {
        device_printf(sc->amr_dev, "can't establish configuration hook\n");
        return(ENOMEM);
    }

    /*
     * Print a little information about the controller.
     */
    amr_describe_controller(sc);

    debug(2, "attach complete");
    return(0);
}

/********************************************************************************
 * Locate disk resources and attach children to them.
 */
static void
amr_startup(void *arg)
{
    struct amr_softc    *sc = (struct amr_softc *)arg;
    struct amr_logdrive *dr;
    int                 i, error;
    
    debug_called(1);

    /* pull ourselves off the intrhook chain */
    if (sc->amr_ich.ich_func)
        config_intrhook_disestablish(&sc->amr_ich);
    sc->amr_ich.ich_func = NULL;

    /* get up-to-date drive information */
    if (amr_query_controller(sc)) {
        device_printf(sc->amr_dev, "can't scan controller for drives\n");
        return;
    }

    /* iterate over available drives */
    for (i = 0, dr = &sc->amr_drive[0]; (i < AMR_MAXLD) && (dr->al_size != 0xffffffff); i++, dr++) {
        /* are we already attached to this drive? */
        if (dr->al_disk == 0) {
            /* generate geometry information */
            if (dr->al_size > 0x200000) {       /* extended translation? */
                dr->al_heads = 255;
                dr->al_sectors = 63;
            } else {
                dr->al_heads = 64;
                dr->al_sectors = 32;
            }
            dr->al_cylinders = dr->al_size / (dr->al_heads * dr->al_sectors);
            
            dr->al_disk = device_add_child(sc->amr_dev, NULL, -1);
            if (dr->al_disk == 0)
                device_printf(sc->amr_dev, "device_add_child failed\n");
            device_set_ivars(dr->al_disk, dr);
        }
    }
    
    if ((error = bus_generic_attach(sc->amr_dev)) != 0)
        device_printf(sc->amr_dev, "bus_generic_attach returned %d\n", error);
    
    /* mark controller back up */
    sc->amr_state &= ~AMR_STATE_SHUTDOWN;

    /* interrupts will be enabled before we do anything more */
    sc->amr_state |= AMR_STATE_INTEN;

    return;
}

static void
amr_init_sysctl(struct amr_softc *sc)
{
    struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->amr_dev);
    struct sysctl_oid *tree = device_get_sysctl_tree(sc->amr_dev);

    SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree),
        OID_AUTO, "allow_volume_configure", CTLFLAG_RW, &sc->amr_allow_vol_config, 0,
        "");
    SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree),
        OID_AUTO, "nextslot", CTLFLAG_RD, &sc->amr_nextslot, 0,
        "");
    SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree),
        OID_AUTO, "busyslots", CTLFLAG_RD, &sc->amr_busyslots, 0,
        "");
    SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree),
        OID_AUTO, "maxio", CTLFLAG_RD, &sc->amr_maxio, 0,
        "");
}


/*******************************************************************************
 * Free resources associated with a controller instance
 */
void
amr_free(struct amr_softc *sc)
{
    struct amr_command_cluster  *acc;

    /* detach from CAM */
    if (sc->amr_pass != NULL)
        device_delete_child(sc->amr_dev, sc->amr_pass);

    /* throw away any command buffers */
    while ((acc = TAILQ_FIRST(&sc->amr_cmd_clusters)) != NULL) {
        TAILQ_REMOVE(&sc->amr_cmd_clusters, acc, acc_link);
        amr_freecmd_cluster(acc);
    }

    /* destroy control device */
    if(sc->amr_dev_t != NULL)
            destroy_dev(sc->amr_dev_t);
    dev_ops_remove_minor(&amr_ops, device_get_unit(sc->amr_dev));

#if 0 /* XXX swildner */
    if (mtx_initialized(&sc->amr_hw_lock))
        mtx_destroy(&sc->amr_hw_lock);

    if (mtx_initialized(&sc->amr_list_lock))
        mtx_destroy(&sc->amr_list_lock);
#endif

    lockuninit(&sc->amr_hw_lock);
    lockuninit(&sc->amr_list_lock);
}

/*******************************************************************************
 * Receive a bio structure from a child device and queue it on a particular
 * disk resource, then poke the disk resource to start as much work as it can.
 */
int
amr_submit_bio(struct amr_softc *sc, struct bio *bio)
{
    debug_called(2);

    lockmgr(&sc->amr_list_lock, LK_EXCLUSIVE);
    amr_enqueue_bio(sc, bio);
    amr_startio(sc);
    lockmgr(&sc->amr_list_lock, LK_RELEASE);
    return(0);
}

/********************************************************************************
 * Accept an open operation on the control device.
 */
static int
amr_open(struct dev_open_args *ap)
{
    cdev_t              dev = ap->a_head.a_dev;
    int                 unit = minor(dev);
    struct amr_softc    *sc = devclass_get_softc(devclass_find("amr"), unit);

    debug_called(1);

    sc->amr_state |= AMR_STATE_OPEN;
    return(0);
}

/********************************************************************************
 * Accept the last close on the control device.
 */
static int
amr_close(struct dev_close_args *ap)
{
    cdev_t              dev = ap->a_head.a_dev;
    int                 unit = minor(dev);
    struct amr_softc    *sc = devclass_get_softc(devclass_find("amr"), unit);

    debug_called(1);

    sc->amr_state &= ~AMR_STATE_OPEN;
    return (0);
}

/********************************************************************************
 * Handle controller-specific control operations.
 */
static void
amr_rescan_drives(struct cdev *dev)
{
    struct amr_softc    *sc = (struct amr_softc *)dev->si_drv1;
    int                 i, error = 0;

    sc->amr_state |= AMR_STATE_REMAP_LD;
    while (sc->amr_busyslots) {
        device_printf(sc->amr_dev, "idle controller\n");
        amr_done(sc);
    }

    /* mark ourselves as in-shutdown */
    sc->amr_state |= AMR_STATE_SHUTDOWN;

    /* flush controller */
    device_printf(sc->amr_dev, "flushing cache...");
    kprintf("%s\n", amr_flush(sc) ? "failed" : "done");

    /* delete all our child devices */
    for(i = 0 ; i < AMR_MAXLD; i++) {
        if(sc->amr_drive[i].al_disk != 0) {
            if((error = device_delete_child(sc->amr_dev,
                sc->amr_drive[i].al_disk)) != 0)
                goto shutdown_out;

             sc->amr_drive[i].al_disk = 0;
        }
    }

shutdown_out:
    amr_startup(sc);
}

/*
 * Bug-for-bug compatibility with Linux!
 * Some apps will send commands with inlen and outlen set to 0,
 * even though they expect data to be transfered to them from the
 * card.  Linux accidentally allows this by allocating a 4KB
 * buffer for the transfer anyways, but it then throws it away
 * without copying it back to the app.
 *
 * The amr(4) firmware relies on this feature.  In fact, it assumes
 * the buffer is always a power of 2 up to a max of 64k.  There is
 * also at least one case where it assumes a buffer less than 16k is
 * greater than 16k.  Force a minimum buffer size of 32k and round
 * sizes between 32k and 64k up to 64k as a workaround.
 */
static unsigned long
amr_ioctl_buffer_length(unsigned long len)
{

    if (len <= 32 * 1024)
        return (32 * 1024);
    if (len <= 64 * 1024)
        return (64 * 1024);
    return (len);
}

static int
amr_linux_ioctl_int(struct cdev *dev, u_long cmd, caddr_t addr, int32_t flag,
    struct sysmsg *sm)
{
    struct amr_softc            *sc = (struct amr_softc *)dev->si_drv1;
    struct amr_command          *ac;
    struct amr_mailbox          *mb;
    struct amr_linux_ioctl      ali;
    void                        *dp, *temp;
    int                         error;
    int                         len, ac_flags = 0;
    int                         logical_drives_changed = 0;
    u_int32_t                   linux_version = 0x02100000;
    u_int8_t                    status;
    struct amr_passthrough      *ap;    /* 60 bytes */

    error = 0;
    dp = NULL;
    ac = NULL;
    ap = NULL;

    if ((error = copyin(addr, &ali, sizeof(ali))) != 0)
        return (error);
    switch (ali.ui.fcs.opcode) {
    case 0x82:
        switch(ali.ui.fcs.subopcode) {
        case 'e':
            copyout(&linux_version, (void *)(uintptr_t)ali.data,
                sizeof(linux_version));
            error = 0;
            break;

        case 'm':
            copyout(&linux_no_adapter, (void *)(uintptr_t)ali.data,
                sizeof(linux_no_adapter));
            sm->sysmsg_result = linux_no_adapter;
            error = 0;
            break;

        default:
            kprintf("Unknown subopcode\n");
            error = ENOIOCTL;
            break;
        }
    break;

    case 0x80:
    case 0x81:
        if (ali.ui.fcs.opcode == 0x80)
            len = max(ali.outlen, ali.inlen);
        else
            len = ali.ui.fcs.length;

        mb = (void *)&ali.mbox[0];

        if ((ali.mbox[0] == FC_DEL_LOGDRV  && ali.mbox[2] == OP_DEL_LOGDRV) ||  /* delete */
            (ali.mbox[0] == AMR_CMD_CONFIG && ali.mbox[2] == 0x0d)) {           /* create */
            if (sc->amr_allow_vol_config == 0) {
                error = EPERM;
                break;
            }
            logical_drives_changed = 1;
        }

        if (ali.mbox[0] == AMR_CMD_PASS) {
            lockmgr(&sc->amr_list_lock, LK_EXCLUSIVE);
            while ((ac = amr_alloccmd(sc)) == NULL)
                lksleep(sc, &sc->amr_list_lock, 0, "amrioc", hz);
            lockmgr(&sc->amr_list_lock, LK_RELEASE);
            ap = &ac->ac_ccb->ccb_pthru;

            error = copyin((void *)(uintptr_t)mb->mb_physaddr, ap,
                sizeof(struct amr_passthrough));
            if (error)
                break;

            if (ap->ap_data_transfer_length)
                dp = kmalloc(ap->ap_data_transfer_length, M_AMR,
                    M_WAITOK | M_ZERO);

            if (ali.inlen) {
                error = copyin((void *)(uintptr_t)ap->ap_data_transfer_address,
                    dp, ap->ap_data_transfer_length);
                if (error)
                    break;
            }

            ac_flags = AMR_CMD_DATAIN|AMR_CMD_DATAOUT|AMR_CMD_CCB;
            bzero(&ac->ac_mailbox, sizeof(ac->ac_mailbox));
            ac->ac_mailbox.mb_command = AMR_CMD_PASS;
            ac->ac_flags = ac_flags;

            ac->ac_data = dp;
            ac->ac_length = ap->ap_data_transfer_length;
            temp = (void *)(uintptr_t)ap->ap_data_transfer_address;

            lockmgr(&sc->amr_list_lock, LK_EXCLUSIVE);
            error = amr_wait_command(ac);
            lockmgr(&sc->amr_list_lock, LK_RELEASE);
            if (error)
                break;

            status = ac->ac_status;
            error = copyout(&status, &((struct amr_passthrough *)(uintptr_t)mb->mb_physaddr)->ap_scsi_status, sizeof(status));
            if (error)
                break;

            if (ali.outlen) {
                error = copyout(dp, temp, ap->ap_data_transfer_length);
                if (error)
                    break;
            }
            error = copyout(ap->ap_request_sense_area, ((struct amr_passthrough *)(uintptr_t)mb->mb_physaddr)->ap_request_sense_area, ap->ap_request_sense_length);
            if (error)
                break;

            error = 0;
            break;
        } else if (ali.mbox[0] == AMR_CMD_PASS_64) {
            kprintf("No AMR_CMD_PASS_64\n");
            error = ENOIOCTL;
            break;
        } else if (ali.mbox[0] == AMR_CMD_EXTPASS) {
            kprintf("No AMR_CMD_EXTPASS\n");
            error = ENOIOCTL;
            break;
        } else {
            len = amr_ioctl_buffer_length(imax(ali.inlen, ali.outlen));

            dp = kmalloc(len, M_AMR, M_WAITOK | M_ZERO);

            if (ali.inlen) {
                error = copyin((void *)(uintptr_t)mb->mb_physaddr, dp, len);
                if (error)
                    break;
            }

            lockmgr(&sc->amr_list_lock, LK_EXCLUSIVE);
            while ((ac = amr_alloccmd(sc)) == NULL)
                lksleep(sc, &sc->amr_list_lock, 0, "amrioc", hz);

            ac_flags = AMR_CMD_DATAIN|AMR_CMD_DATAOUT;
            bzero(&ac->ac_mailbox, sizeof(ac->ac_mailbox));
            bcopy(&ali.mbox[0], &ac->ac_mailbox, sizeof(ali.mbox));

            ac->ac_length = len;
            ac->ac_data = dp;
            ac->ac_flags = ac_flags;

            error = amr_wait_command(ac);
            lockmgr(&sc->amr_list_lock, LK_RELEASE);
            if (error)
                break;

            status = ac->ac_status;
            error = copyout(&status, &((struct amr_mailbox *)&((struct amr_linux_ioctl *)addr)->mbox[0])->mb_status, sizeof(status));
            if (ali.outlen) {
                error = copyout(dp, (void *)(uintptr_t)mb->mb_physaddr, ali.outlen);
                if (error)
                    break;
            }

            error = 0;
            if (logical_drives_changed)
                amr_rescan_drives(dev);
            break;
        }
        break;

    default:
        debug(1, "unknown linux ioctl 0x%lx", cmd);
        kprintf("unknown linux ioctl 0x%lx\n", cmd);
        error = ENOIOCTL;
        break;
    }

    /*
     * At this point, we know that there is a lock held and that these
     * objects have been allocated.
     */
    lockmgr(&sc->amr_list_lock, LK_EXCLUSIVE);
    if (ac != NULL)
        amr_releasecmd(ac);
    lockmgr(&sc->amr_list_lock, LK_RELEASE);
    if (dp != NULL)
        kfree(dp, M_AMR);
    return(error);
}

static int
amr_ioctl(struct dev_ioctl_args *ap)
{
    cdev_t                      dev = ap->a_head.a_dev;
    caddr_t                     addr = ap->a_data;
    u_long                      cmd = ap->a_cmd;
    struct amr_softc            *sc = (struct amr_softc *)dev->si_drv1;
    union {
        void                    *_p;
        struct amr_user_ioctl   *au;
#ifdef AMR_IO_COMMAND32
        struct amr_user_ioctl32 *au32;
#endif
        int                     *result;
    } arg;
    struct amr_command          *ac;
    struct amr_mailbox_ioctl    *mbi;
    void                        *dp, *au_buffer;
    unsigned long               au_length, real_length;
    unsigned char               *au_cmd;
    int                         *au_statusp;
    int                         error;
    struct amr_passthrough      *_ap;   /* 60 bytes */
    int                         logical_drives_changed = 0;

    debug_called(1);

    arg._p = (void *)addr;

    error = 0;
    dp = NULL;
    ac = NULL;
    _ap = NULL;

    switch(cmd) {

    case AMR_IO_VERSION:
        debug(1, "AMR_IO_VERSION");
        *arg.result = AMR_IO_VERSION_NUMBER;
        return(0);

#ifdef AMR_IO_COMMAND32
    /*
     * Accept ioctl-s from 32-bit binaries on non-32-bit
     * platforms, such as AMD. LSI's MEGAMGR utility is
     * the only example known today...  -mi
     */
    case AMR_IO_COMMAND32:
        debug(1, "AMR_IO_COMMAND32 0x%x", arg.au32->au_cmd[0]);
        au_cmd = arg.au32->au_cmd;
        au_buffer = (void *)(u_int64_t)arg.au32->au_buffer;
        au_length = arg.au32->au_length;
        au_statusp = &arg.au32->au_status;
        break;
#endif

    case AMR_IO_COMMAND:
        debug(1, "AMR_IO_COMMAND  0x%x", arg.au->au_cmd[0]);
        au_cmd = arg.au->au_cmd;
        au_buffer = (void *)arg.au->au_buffer;
        au_length = arg.au->au_length;
        au_statusp = &arg.au->au_status;
        break;

    case 0xc0046d00:
    case 0xc06e6d00:    /* Linux emulation */
        {
            devclass_t                  devclass;
            struct amr_linux_ioctl      ali;
            int                         adapter, error;

            devclass = devclass_find("amr");
            if (devclass == NULL)
                return (ENOENT);

            error = copyin(addr, &ali, sizeof(ali));
            if (error)
                return (error);
            if (ali.ui.fcs.opcode == 0x82)
                adapter = 0;
            else
                adapter = (ali.ui.fcs.adapno) ^ 'm' << 8;

            sc = devclass_get_softc(devclass, adapter);
            if (sc == NULL)
                return (ENOENT);

            return (amr_linux_ioctl_int(sc->amr_dev_t, cmd, addr, 0, ap->a_sysmsg));
        }
    default:
        debug(1, "unknown ioctl 0x%lx", cmd);
        return(ENOIOCTL);
    }

    if ((au_cmd[0] == FC_DEL_LOGDRV && au_cmd[1] == OP_DEL_LOGDRV) ||   /* delete */
        (au_cmd[0] == AMR_CMD_CONFIG && au_cmd[1] == 0x0d)) {           /* create */
        if (sc->amr_allow_vol_config == 0) {
            error = EPERM;
            goto out;
        }
        logical_drives_changed = 1;
    }

    /* handle inbound data buffer */
    real_length = amr_ioctl_buffer_length(au_length);
    if (au_length != 0 && au_cmd[0] != 0x06) {
        if ((dp = kmalloc(real_length, M_AMR, M_WAITOK|M_ZERO)) == NULL) {
            error = ENOMEM;
            goto out;
        }
        if ((error = copyin(au_buffer, dp, au_length)) != 0) {
            kfree(dp, M_AMR);
            return (error);
        }
        debug(2, "copyin %ld bytes from %p -> %p", au_length, au_buffer, dp);
    }

    /* Allocate this now before the mutex gets held */

    lockmgr(&sc->amr_list_lock, LK_EXCLUSIVE);
    while ((ac = amr_alloccmd(sc)) == NULL)
        lksleep(sc, &sc->amr_list_lock, 0, "amrioc", hz);

    /* handle SCSI passthrough command */
    if (au_cmd[0] == AMR_CMD_PASS) {
        int len;

        _ap = &ac->ac_ccb->ccb_pthru;
        bzero(_ap, sizeof(struct amr_passthrough));

        /* copy cdb */
        len = au_cmd[2];
        _ap->ap_cdb_length = len;
        bcopy(au_cmd + 3, _ap->ap_cdb, len);

        /* build passthrough */
        _ap->ap_timeout         = au_cmd[len + 3] & 0x07;
        _ap->ap_ars             = (au_cmd[len + 3] & 0x08) ? 1 : 0;
        _ap->ap_islogical       = (au_cmd[len + 3] & 0x80) ? 1 : 0;
        _ap->ap_logical_drive_no = au_cmd[len + 4];
        _ap->ap_channel         = au_cmd[len + 5];
        _ap->ap_scsi_id         = au_cmd[len + 6];
        _ap->ap_request_sense_length    = 14;
        _ap->ap_data_transfer_length    = au_length;
        /* XXX what about the request-sense area? does the caller want it? */

        /* build command */
        ac->ac_mailbox.mb_command = AMR_CMD_PASS;
        ac->ac_flags = AMR_CMD_CCB;

    } else {
        /* direct command to controller */
        mbi = (struct amr_mailbox_ioctl *)&ac->ac_mailbox;

        /* copy pertinent mailbox items */
        mbi->mb_command = au_cmd[0];
        mbi->mb_channel = au_cmd[1];
        mbi->mb_param = au_cmd[2];
        mbi->mb_pad[0] = au_cmd[3];
        mbi->mb_drive = au_cmd[4];
        ac->ac_flags = 0;
    }

    /* build the command */
    ac->ac_data = dp;
    ac->ac_length = real_length;
    ac->ac_flags |= AMR_CMD_DATAIN|AMR_CMD_DATAOUT;

    /* run the command */
    error = amr_wait_command(ac);
    lockmgr(&sc->amr_list_lock, LK_RELEASE);
    if (error)
        goto out;

    /* copy out data and set status */
    if (au_length != 0) {
        error = copyout(dp, au_buffer, au_length);
    }
    debug(2, "copyout %ld bytes from %p -> %p", au_length, dp, au_buffer);
    if (dp != NULL)
        debug(2, "%p status 0x%x", dp, ac->ac_status);
    *au_statusp = ac->ac_status;

out:
    /*
     * At this point, we know that there is a lock held and that these
     * objects have been allocated.
     */
    lockmgr(&sc->amr_list_lock, LK_EXCLUSIVE);
    if (ac != NULL)
        amr_releasecmd(ac);
    lockmgr(&sc->amr_list_lock, LK_RELEASE);
    if (dp != NULL)
        kfree(dp, M_AMR);

    if (logical_drives_changed)
        amr_rescan_drives(dev);

    return(error);
}

/********************************************************************************
 ********************************************************************************
                                                                 Command Wrappers
 ********************************************************************************
 ********************************************************************************/

/********************************************************************************
 * Interrogate the controller for the operational parameters we require.
 */
static int
amr_query_controller(struct amr_softc *sc)
{
    struct amr_enquiry3 *aex;
    struct amr_prodinfo *ap;
    struct amr_enquiry  *ae;
    int                 ldrv;
    int                 status;

    /*
     * Greater than 10 byte cdb support
     */
    sc->support_ext_cdb = amr_support_ext_cdb(sc);

    if(sc->support_ext_cdb) {
        debug(2,"supports extended CDBs.");
    }

    /* 
     * Try to issue an ENQUIRY3 command 
     */
    if ((aex = amr_enquiry(sc, 2048, AMR_CMD_CONFIG, AMR_CONFIG_ENQ3, 
                           AMR_CONFIG_ENQ3_SOLICITED_FULL, &status)) != NULL) {

        /*
         * Fetch current state of logical drives.
         */
        for (ldrv = 0; ldrv < aex->ae_numldrives; ldrv++) {
            sc->amr_drive[ldrv].al_size       = aex->ae_drivesize[ldrv];
            sc->amr_drive[ldrv].al_state      = aex->ae_drivestate[ldrv];
            sc->amr_drive[ldrv].al_properties = aex->ae_driveprop[ldrv];
            debug(2, "  drive %d: %d state %x properties %x", ldrv, sc->amr_drive[ldrv].al_size,
                  sc->amr_drive[ldrv].al_state, sc->amr_drive[ldrv].al_properties);
        }
        kfree(aex, M_AMR);

        /*
         * Get product info for channel count.
         */
        if ((ap = amr_enquiry(sc, 2048, AMR_CMD_CONFIG, AMR_CONFIG_PRODUCT_INFO, 0, &status)) == NULL) {
            device_printf(sc->amr_dev, "can't obtain product data from controller\n");
            return(1);
        }
        sc->amr_maxdrives = 40;
        sc->amr_maxchan = ap->ap_nschan;
        sc->amr_maxio = ap->ap_maxio;
        sc->amr_type |= AMR_TYPE_40LD;
        kfree(ap, M_AMR);

        ap = amr_enquiry(sc, 0, FC_DEL_LOGDRV, OP_SUP_DEL_LOGDRV, 0, &status);
        if (ap != NULL)
            kfree(ap, M_AMR);
        if (!status) {
            sc->amr_ld_del_supported = 1;
            device_printf(sc->amr_dev, "delete logical drives supported by controller\n");
        }
    } else {

        /* failed, try the 8LD ENQUIRY commands */
        if ((ae = (struct amr_enquiry *)amr_enquiry(sc, 2048, AMR_CMD_EXT_ENQUIRY2, 0, 0, &status)) == NULL) {
            if ((ae = (struct amr_enquiry *)amr_enquiry(sc, 2048, AMR_CMD_ENQUIRY, 0, 0, &status)) == NULL) {
                device_printf(sc->amr_dev, "can't obtain configuration data from controller\n");
                return(1);
            }
            ae->ae_signature = 0;
        }

        /*
         * Fetch current state of logical drives.
         */
        for (ldrv = 0; ldrv < ae->ae_ldrv.al_numdrives; ldrv++) {
            sc->amr_drive[ldrv].al_size       = ae->ae_ldrv.al_size[ldrv];
            sc->amr_drive[ldrv].al_state      = ae->ae_ldrv.al_state[ldrv];
            sc->amr_drive[ldrv].al_properties = ae->ae_ldrv.al_properties[ldrv];
            debug(2, "  drive %d: %d state %x properties %x\n", ldrv, sc->amr_drive[ldrv].al_size,
                  sc->amr_drive[ldrv].al_state, sc->amr_drive[ldrv].al_properties);
        }

        sc->amr_maxdrives = 8;
        sc->amr_maxchan = ae->ae_adapter.aa_channels;
        sc->amr_maxio = ae->ae_adapter.aa_maxio;
        kfree(ae, M_AMR);
    }

    /*
     * Mark remaining drives as unused.
     */
    for (; ldrv < AMR_MAXLD; ldrv++)
        sc->amr_drive[ldrv].al_size = 0xffffffff;

    /* 
     * Cap the maximum number of outstanding I/Os.  AMI's Linux driver doesn't trust
     * the controller's reported value, and lockups have been seen when we do.
     */
    sc->amr_maxio = imin(sc->amr_maxio, AMR_LIMITCMD);

    return(0);
}

/********************************************************************************
 * Run a generic enquiry-style command.
 */
static void *
amr_enquiry(struct amr_softc *sc, size_t bufsize, u_int8_t cmd, u_int8_t cmdsub, u_int8_t cmdqual, int *status)
{
    struct amr_command  *ac;
    void                *result;
    u_int8_t            *mbox;
    int                 error;

    debug_called(1);

    *status = 0;        /* avoid gcc warnings */
    error = 1;
    result = NULL;
    
    /* get ourselves a command buffer */
    lockmgr(&sc->amr_list_lock, LK_EXCLUSIVE);
    ac = amr_alloccmd(sc);
    lockmgr(&sc->amr_list_lock, LK_RELEASE);
    if (ac == NULL)
        goto out;
    /* allocate the response structure */
    if ((result = kmalloc(bufsize, M_AMR, M_ZERO|M_NOWAIT)) == NULL)
        goto out;
    /* set command flags */

    ac->ac_flags |= AMR_CMD_PRIORITY | AMR_CMD_DATAIN;
    
    /* point the command at our data */
    ac->ac_data = result;
    ac->ac_length = bufsize;
    
    /* build the command proper */
    mbox = (u_int8_t *)&ac->ac_mailbox;         /* XXX want a real structure for this? */
    mbox[0] = cmd;
    mbox[2] = cmdsub;
    mbox[3] = cmdqual;
    *status = 0;

    /* can't assume that interrupts are going to work here, so play it safe */
    if (sc->amr_poll_command(ac))
        goto out;
    error = ac->ac_status;
    *status = ac->ac_status;
    
 out:
    lockmgr(&sc->amr_list_lock, LK_EXCLUSIVE);
    if (ac != NULL)
        amr_releasecmd(ac);
    lockmgr(&sc->amr_list_lock, LK_RELEASE);
    if ((error != 0) && (result != NULL)) {
        kfree(result, M_AMR);
        result = NULL;
    }
    return(result);
}

/********************************************************************************
 * Flush the controller's internal cache, return status.
 */
int
amr_flush(struct amr_softc *sc)
{
    struct amr_command  *ac;
    int                 error;

    /* get ourselves a command buffer */
    error = 1;
    lockmgr(&sc->amr_list_lock, LK_EXCLUSIVE);
    ac = amr_alloccmd(sc);
    lockmgr(&sc->amr_list_lock, LK_RELEASE);
    if (ac == NULL)
        goto out;
    /* set command flags */
    ac->ac_flags |= AMR_CMD_PRIORITY | AMR_CMD_DATAOUT;
    
    /* build the command proper */
    ac->ac_mailbox.mb_command = AMR_CMD_FLUSH;

    /* we have to poll, as the system may be going down or otherwise damaged */
    if (sc->amr_poll_command(ac))
        goto out;
    error = ac->ac_status;
    
 out:
    lockmgr(&sc->amr_list_lock, LK_EXCLUSIVE);
    if (ac != NULL)
        amr_releasecmd(ac);
    lockmgr(&sc->amr_list_lock, LK_RELEASE);
    return(error);
}

/********************************************************************************
 * Detect extented cdb >> greater than 10 byte cdb support
 * returns '1' means this support exist
 * returns '0' means this support doesn't exist
 */
static int
amr_support_ext_cdb(struct amr_softc *sc)
{
    struct amr_command  *ac;
    u_int8_t            *mbox;
    int                 error;

    /* get ourselves a command buffer */
    error = 0;
    lockmgr(&sc->amr_list_lock, LK_EXCLUSIVE);
    ac = amr_alloccmd(sc);
    lockmgr(&sc->amr_list_lock, LK_RELEASE);
    if (ac == NULL)
        goto out;
    /* set command flags */
    ac->ac_flags |= AMR_CMD_PRIORITY | AMR_CMD_DATAOUT;

    /* build the command proper */
    mbox = (u_int8_t *)&ac->ac_mailbox;         /* XXX want a real structure for this? */
    mbox[0] = 0xA4;
    mbox[2] = 0x16;


    /* we have to poll, as the system may be going down or otherwise damaged */
    if (sc->amr_poll_command(ac))
        goto out;
    if( ac->ac_status == AMR_STATUS_SUCCESS ) {
            error = 1;
    }

out:
    lockmgr(&sc->amr_list_lock, LK_EXCLUSIVE);
    if (ac != NULL)
        amr_releasecmd(ac);
    lockmgr(&sc->amr_list_lock, LK_RELEASE);
    return(error);
}

/********************************************************************************
 * Try to find I/O work for the controller from one or more of the work queues.
 *
 * We make the assumption that if the controller is not ready to take a command
 * at some given time, it will generate an interrupt at some later time when
 * it is.
 */
void
amr_startio(struct amr_softc *sc)
{
    struct amr_command  *ac;

    /* spin until something prevents us from doing any work */
    for (;;) {

        /* Don't bother to queue commands no bounce buffers are available. */
        if (sc->amr_state & AMR_STATE_QUEUE_FRZN)
            break;

        /* try to get a ready command */
        ac = amr_dequeue_ready(sc);

        /* if that failed, build a command from a bio */
        if (ac == NULL)
            (void)amr_bio_command(sc, &ac);

        /* if that failed, build a command from a ccb */
        if ((ac == NULL) && (sc->amr_cam_command != NULL))
            sc->amr_cam_command(sc, &ac);

        /* if we don't have anything to do, give up */
        if (ac == NULL)
            break;

        /* try to give the command to the controller; if this fails save it for later and give up */
        if (amr_start(ac)) {
            debug(2, "controller busy, command deferred");
            amr_requeue_ready(ac);      /* XXX schedule retry very soon? */
            break;
        }
    }
}

/********************************************************************************
 * Handle completion of an I/O command.
 */
static void
amr_completeio(struct amr_command *ac)
{
    struct amr_softc            *sc = ac->ac_sc;
    static struct timeval       lastfail;
    static int                  curfail;
    struct buf                  *bp = ac->ac_bio->bio_buf;

    if (ac->ac_status != AMR_STATUS_SUCCESS) {  /* could be more verbose here? */
        bp->b_error = EIO;
        bp->b_flags |= B_ERROR;

        if (ppsratecheck(&lastfail, &curfail, 1))
            device_printf(sc->amr_dev, "I/O error - 0x%x\n", ac->ac_status);
/*      amr_printcommand(ac);*/
    }
    amrd_intr(ac->ac_bio);
    lockmgr(&ac->ac_sc->amr_list_lock, LK_EXCLUSIVE);
    amr_releasecmd(ac);
    lockmgr(&ac->ac_sc->amr_list_lock, LK_RELEASE);
}

/********************************************************************************
 ********************************************************************************
                                                               Command Processing
 ********************************************************************************
 ********************************************************************************/

/********************************************************************************
 * Convert a bio off the top of the bio queue into a command.
 */
static int
amr_bio_command(struct amr_softc *sc, struct amr_command **acp)
{
    struct amr_command  *ac;
    struct amrd_softc   *amrd;
    struct bio          *bio;
    struct buf          *bp;
    int                 error;
    int                 blkcount;
    int                 driveno;
    int                 cmd;

    ac = NULL;
    error = 0;

    /* get a command */
    if ((ac = amr_alloccmd(sc)) == NULL)
        return (ENOMEM);

    /* get a bio to work on */
    if ((bio = amr_dequeue_bio(sc)) == NULL) {
        amr_releasecmd(ac);
        return (0);
    }

    /* connect the bio to the command */
    bp = bio->bio_buf;
    ac->ac_complete = amr_completeio;
    ac->ac_bio = bio;
    ac->ac_data = bp->b_data;
    ac->ac_length = bp->b_bcount;
    cmd = 0;
    switch (bp->b_cmd) {
    case BUF_CMD_READ:
        ac->ac_flags |= AMR_CMD_DATAIN;
        if (AMR_IS_SG64(sc)) {
            cmd = AMR_CMD_LREAD64;
            ac->ac_flags |= AMR_CMD_SG64;
        } else
            cmd = AMR_CMD_LREAD;
        break;
    case BUF_CMD_WRITE:
        ac->ac_flags |= AMR_CMD_DATAOUT;
        if (AMR_IS_SG64(sc)) {
            cmd = AMR_CMD_LWRITE64;
            ac->ac_flags |= AMR_CMD_SG64;
        } else
            cmd = AMR_CMD_LWRITE;
        break;
    case BUF_CMD_FLUSH:
        ac->ac_flags |= AMR_CMD_PRIORITY | AMR_CMD_DATAOUT;
        cmd = AMR_CMD_FLUSH;
        break;
    default:
        panic("Invalid bio command");
    }
    amrd = (struct amrd_softc *)bio->bio_driver_info;
    driveno = amrd->amrd_drive - sc->amr_drive;
    blkcount = (bp->b_bcount + AMR_BLKSIZE - 1) / AMR_BLKSIZE;

    ac->ac_mailbox.mb_command = cmd;
    if (bp->b_cmd & (BUF_CMD_READ|BUF_CMD_WRITE)) {
        ac->ac_mailbox.mb_blkcount = blkcount;
        ac->ac_mailbox.mb_lba = bio->bio_offset / AMR_BLKSIZE;
        if (((bio->bio_offset / AMR_BLKSIZE) + blkcount) > sc->amr_drive[driveno].al_size) {
            device_printf(sc->amr_dev,
                          "I/O beyond end of unit (%lld,%d > %lu)\n",
                          (long long)(bio->bio_offset / AMR_BLKSIZE), blkcount,
                          (u_long)sc->amr_drive[driveno].al_size);
        }
    }
    ac->ac_mailbox.mb_drive = driveno;
    if (sc->amr_state & AMR_STATE_REMAP_LD)
        ac->ac_mailbox.mb_drive |= 0x80;

    /* we fill in the s/g related data when the command is mapped */


    *acp = ac;
    return(error);
}

/********************************************************************************
 * Take a command, submit it to the controller and sleep until it completes
 * or fails.  Interrupts must be enabled, returns nonzero on error.
 */
static int
amr_wait_command(struct amr_command *ac)
{
    int                 error = 0;
    struct amr_softc    *sc = ac->ac_sc;

    debug_called(1);

    ac->ac_complete = NULL;
    ac->ac_flags |= AMR_CMD_SLEEP;
    if ((error = amr_start(ac)) != 0) {
        return(error);
    }
    
    while ((ac->ac_flags & AMR_CMD_BUSY) && (error != EWOULDBLOCK)) {
        error = lksleep(ac,&sc->amr_list_lock, 0, "amrwcmd", 0);
    }

    return(error);
}

/********************************************************************************
 * Take a command, submit it to the controller and busy-wait for it to return.
 * Returns nonzero on error.  Can be safely called with interrupts enabled.
 */
static int
amr_std_poll_command(struct amr_command *ac)
{
    struct amr_softc    *sc = ac->ac_sc;
    int                 error, count;

    debug_called(2);

    ac->ac_complete = NULL;
    if ((error = amr_start(ac)) != 0)
        return(error);

    count = 0;
    do {
        /* 
         * Poll for completion, although the interrupt handler may beat us to it. 
         * Note that the timeout here is somewhat arbitrary.
         */
        amr_done(sc);
        DELAY(1000);
    } while ((ac->ac_flags & AMR_CMD_BUSY) && (count++ < 1000));
    if (!(ac->ac_flags & AMR_CMD_BUSY)) {
        error = 0;
    } else {
        /* XXX the slot is now marked permanently busy */
        error = EIO;
        device_printf(sc->amr_dev, "polled command timeout\n");
    }
    return(error);
}

static void
amr_setup_polled_dmamap(void *arg, bus_dma_segment_t *segs, int nsegs, int err)
{
    struct amr_command *ac = arg;
    struct amr_softc *sc = ac->ac_sc;
    int mb_channel;

    if (err) {
        device_printf(sc->amr_dev, "error %d in %s", err, __func__);
        ac->ac_status = AMR_STATUS_ABORTED;
        return;
    }

    amr_setup_sg(arg, segs, nsegs, err);

    /* for AMR_CMD_CONFIG Read/Write the s/g count goes elsewhere */
    mb_channel = ((struct amr_mailbox_ioctl *)&ac->ac_mailbox)->mb_channel;
    if (ac->ac_mailbox.mb_command == AMR_CMD_CONFIG &&
        ((mb_channel == AMR_CONFIG_READ_NVRAM_CONFIG) ||
        (mb_channel == AMR_CONFIG_WRITE_NVRAM_CONFIG)))
        ((struct amr_mailbox_ioctl *)&ac->ac_mailbox)->mb_param = ac->ac_nsegments;

    ac->ac_mailbox.mb_nsgelem = ac->ac_nsegments;
    ac->ac_mailbox.mb_physaddr = ac->ac_mb_physaddr;
    if (AC_IS_SG64(ac)) {
        ac->ac_sg64_hi = 0;
        ac->ac_sg64_lo = ac->ac_sgbusaddr;
    }

    sc->amr_poll_command1(sc, ac);
}

/********************************************************************************
 * Take a command, submit it to the controller and busy-wait for it to return.
 * Returns nonzero on error.  Can be safely called with interrupts enabled.
 */
static int
amr_quartz_poll_command(struct amr_command *ac)
{
    struct amr_softc    *sc = ac->ac_sc;
    int                 error;

    debug_called(2);

    error = 0;

    if (AC_IS_SG64(ac)) {
        ac->ac_tag = sc->amr_buffer64_dmat;
        ac->ac_datamap = ac->ac_dma64map;
    } else {
        ac->ac_tag = sc->amr_buffer_dmat;
        ac->ac_datamap = ac->ac_dmamap;
    }

    /* now we have a slot, we can map the command (unmapped in amr_complete) */
    if (ac->ac_data != NULL && ac->ac_length != 0) {
        if (bus_dmamap_load(ac->ac_tag, ac->ac_datamap, ac->ac_data,
            ac->ac_length, amr_setup_polled_dmamap, ac, BUS_DMA_NOWAIT) != 0) {
            error = 1;
        }
    } else {
        error = amr_quartz_poll_command1(sc, ac);
    }

    return (error);
}

static int
amr_quartz_poll_command1(struct amr_softc *sc, struct amr_command *ac)
{
    int count, error;

    lockmgr(&sc->amr_hw_lock, LK_EXCLUSIVE);
    if ((sc->amr_state & AMR_STATE_INTEN) == 0) {
        count=0;
        while (sc->amr_busyslots) {
            lksleep(sc, &sc->amr_hw_lock, PCATCH, "amrpoll", hz);
            if(count++>10) {
                break;
            }
        }

        if(sc->amr_busyslots) {
            device_printf(sc->amr_dev, "adapter is busy\n");
            lockmgr(&sc->amr_hw_lock, LK_RELEASE);
            if (ac->ac_data != NULL) {
                bus_dmamap_unload(ac->ac_tag, ac->ac_datamap);
            }
            ac->ac_status=0;
            return(1);
        }
    }

    bcopy(&ac->ac_mailbox, (void *)(uintptr_t)(volatile void *)sc->amr_mailbox, AMR_MBOX_CMDSIZE);

    /* clear the poll/ack fields in the mailbox */
    sc->amr_mailbox->mb_ident = 0xFE;
    sc->amr_mailbox->mb_nstatus = 0xFF;
    sc->amr_mailbox->mb_status = 0xFF;
    sc->amr_mailbox->mb_poll = 0;
    sc->amr_mailbox->mb_ack = 0;
    sc->amr_mailbox->mb_busy = 1;

    AMR_QPUT_IDB(sc, sc->amr_mailboxphys | AMR_QIDB_SUBMIT);

    while(sc->amr_mailbox->mb_nstatus == 0xFF)
        DELAY(1);
    while(sc->amr_mailbox->mb_status == 0xFF)
        DELAY(1);
    ac->ac_status=sc->amr_mailbox->mb_status;
    error = (ac->ac_status !=AMR_STATUS_SUCCESS) ? 1:0;
    while(sc->amr_mailbox->mb_poll != 0x77)
        DELAY(1);
    sc->amr_mailbox->mb_poll = 0;
    sc->amr_mailbox->mb_ack = 0x77;

    /* acknowledge that we have the commands */
    AMR_QPUT_IDB(sc, sc->amr_mailboxphys | AMR_QIDB_ACK);
    while(AMR_QGET_IDB(sc) & AMR_QIDB_ACK)
        DELAY(1);
    lockmgr(&sc->amr_hw_lock, LK_RELEASE);

    /* unmap the command's data buffer */
    if (ac->ac_flags & AMR_CMD_DATAIN) {
        bus_dmamap_sync(ac->ac_tag, ac->ac_datamap, BUS_DMASYNC_POSTREAD);
    }
    if (ac->ac_flags & AMR_CMD_DATAOUT) {
        bus_dmamap_sync(ac->ac_tag, ac->ac_datamap, BUS_DMASYNC_POSTWRITE);
    }
    bus_dmamap_unload(ac->ac_tag, ac->ac_datamap);

    return(error);
}

static __inline int
amr_freeslot(struct amr_command *ac)
{
    struct amr_softc *sc = ac->ac_sc;
    int                 slot;

    debug_called(3);

    slot = ac->ac_slot;
    if (sc->amr_busycmd[slot] == NULL)
        panic("amr: slot %d not busy?", slot);

    sc->amr_busycmd[slot] = NULL;
    atomic_subtract_int(&sc->amr_busyslots, 1);

    return (0);
}

/********************************************************************************
 * Map/unmap (ac)'s data in the controller's addressable space as required.
 *
 * These functions may be safely called multiple times on a given command.
 */
static void
amr_setup_sg(void *arg, bus_dma_segment_t *segs, int nsegments, int error)
{
    struct amr_command  *ac = (struct amr_command *)arg;
    struct amr_sgentry  *sg;
    struct amr_sg64entry *sg64;
    int flags, i;

    debug_called(3);

    /* get base address of s/g table */
    sg = ac->ac_sg.sg32;
    sg64 = ac->ac_sg.sg64;

    if (AC_IS_SG64(ac)) {
        ac->ac_nsegments = nsegments;
        ac->ac_mb_physaddr = 0xffffffff;
        for (i = 0; i < nsegments; i++, sg64++) {
            sg64->sg_addr = segs[i].ds_addr;
            sg64->sg_count = segs[i].ds_len;
        }
    } else {
        /* decide whether we need to populate the s/g table */
        if (nsegments < 2) {
            ac->ac_nsegments = 0;
            ac->ac_mb_physaddr = segs[0].ds_addr;
        } else {
            ac->ac_nsegments = nsegments;
            ac->ac_mb_physaddr = ac->ac_sgbusaddr;
            for (i = 0; i < nsegments; i++, sg++) {
                sg->sg_addr = segs[i].ds_addr;
                sg->sg_count = segs[i].ds_len;
            }
        }
    }

    flags = 0;
    if (ac->ac_flags & AMR_CMD_DATAIN)
        flags |= BUS_DMASYNC_PREREAD;
    if (ac->ac_flags & AMR_CMD_DATAOUT)
        flags |= BUS_DMASYNC_PREWRITE;
    bus_dmamap_sync(ac->ac_tag, ac->ac_datamap, flags);
    ac->ac_flags |= AMR_CMD_MAPPED;
}

static void
amr_setup_data(void *arg, bus_dma_segment_t *segs, int nsegs, int err)
{
    struct amr_command *ac = arg;
    struct amr_softc *sc = ac->ac_sc;
    int mb_channel;

    if (err) {
        device_printf(sc->amr_dev, "error %d in %s", err, __func__);
        amr_abort_load(ac);
        return;
    }

    amr_setup_sg(arg, segs, nsegs, err);

    /* for AMR_CMD_CONFIG Read/Write the s/g count goes elsewhere */
    mb_channel = ((struct amr_mailbox_ioctl *)&ac->ac_mailbox)->mb_channel;
    if (ac->ac_mailbox.mb_command == AMR_CMD_CONFIG &&
        ((mb_channel == AMR_CONFIG_READ_NVRAM_CONFIG) ||
        (mb_channel == AMR_CONFIG_WRITE_NVRAM_CONFIG)))
        ((struct amr_mailbox_ioctl *)&ac->ac_mailbox)->mb_param = ac->ac_nsegments;

    ac->ac_mailbox.mb_nsgelem = ac->ac_nsegments;
    ac->ac_mailbox.mb_physaddr = ac->ac_mb_physaddr;
    if (AC_IS_SG64(ac)) {
        ac->ac_sg64_hi = 0;
        ac->ac_sg64_lo = ac->ac_sgbusaddr;
    }

    if (sc->amr_submit_command(ac) == EBUSY) {
        amr_freeslot(ac);
        amr_requeue_ready(ac);
    }
}

static void
amr_setup_ccb(void *arg, bus_dma_segment_t *segs, int nsegs, int err)
{
    struct amr_command *ac = arg;
    struct amr_softc *sc = ac->ac_sc;
    struct amr_passthrough *ap = &ac->ac_ccb->ccb_pthru;
    struct amr_ext_passthrough *aep = &ac->ac_ccb->ccb_epthru;

    if (err) {
        device_printf(sc->amr_dev, "error %d in %s", err, __func__);
        amr_abort_load(ac);
        return;
    }

    /* Set up the mailbox portion of the command to point at the ccb */
    ac->ac_mailbox.mb_nsgelem = 0;
    ac->ac_mailbox.mb_physaddr = ac->ac_ccb_busaddr;

    amr_setup_sg(arg, segs, nsegs, err);

    switch (ac->ac_mailbox.mb_command) {
    case AMR_CMD_EXTPASS:
        aep->ap_no_sg_elements = ac->ac_nsegments;
        aep->ap_data_transfer_address = ac->ac_mb_physaddr;
        break;
    case AMR_CMD_PASS:
        ap->ap_no_sg_elements = ac->ac_nsegments;
        ap->ap_data_transfer_address = ac->ac_mb_physaddr;
        break;
    default:
        panic("Unknown ccb command");
    }

    if (sc->amr_submit_command(ac) == EBUSY) {
        amr_freeslot(ac);
        amr_requeue_ready(ac);
    }
}

static int
amr_mapcmd(struct amr_command *ac)
{
    bus_dmamap_callback_t *cb;
    struct amr_softc    *sc = ac->ac_sc;

    debug_called(3);

    if (AC_IS_SG64(ac)) {
        ac->ac_tag = sc->amr_buffer64_dmat;
        ac->ac_datamap = ac->ac_dma64map;
    } else {
        ac->ac_tag = sc->amr_buffer_dmat;
        ac->ac_datamap = ac->ac_dmamap;
    }

    if (ac->ac_flags & AMR_CMD_CCB)
        cb = amr_setup_ccb;
    else
        cb = amr_setup_data;

    /* if the command involves data at all, and hasn't been mapped */
    if ((ac->ac_flags & AMR_CMD_MAPPED) == 0 && (ac->ac_data != NULL)) {
        /* map the data buffers into bus space and build the s/g list */
        if (bus_dmamap_load(ac->ac_tag, ac->ac_datamap, ac->ac_data,
             ac->ac_length, cb, ac, 0) == EINPROGRESS) {
            sc->amr_state |= AMR_STATE_QUEUE_FRZN;
        }
   } else {
        if (sc->amr_submit_command(ac) == EBUSY) {
            amr_freeslot(ac);
            amr_requeue_ready(ac);
        }
   }

    return (0);
}

static void
amr_unmapcmd(struct amr_command *ac)
{
    int                 flag;

    debug_called(3);

    /* if the command involved data at all and was mapped */
    if (ac->ac_flags & AMR_CMD_MAPPED) {

        if (ac->ac_data != NULL) {

            flag = 0;
            if (ac->ac_flags & AMR_CMD_DATAIN)
                flag |= BUS_DMASYNC_POSTREAD;
            if (ac->ac_flags & AMR_CMD_DATAOUT)
                flag |= BUS_DMASYNC_POSTWRITE;

            bus_dmamap_sync(ac->ac_tag, ac->ac_datamap, flag);
            bus_dmamap_unload(ac->ac_tag, ac->ac_datamap);
        }

        ac->ac_flags &= ~AMR_CMD_MAPPED;
    }
}

static void
amr_abort_load(struct amr_command *ac)
{
    ac_qhead_t head;
    struct amr_softc *sc = ac->ac_sc;

    KKASSERT(lockowned(&sc->amr_list_lock));

    ac->ac_status = AMR_STATUS_ABORTED;
    amr_init_qhead(&head);
    amr_enqueue_completed(ac, &head);

    lockmgr(&sc->amr_list_lock, LK_RELEASE);
    amr_complete(sc, &head);
    lockmgr(&sc->amr_list_lock, LK_EXCLUSIVE);
}

/********************************************************************************
 * Take a command and give it to the controller, returns 0 if successful, or
 * EBUSY if the command should be retried later.
 */
static int
amr_start(struct amr_command *ac)
{
    struct amr_softc *sc;
    int error = 0;
    int slot;

    debug_called(3);

    /* mark command as busy so that polling consumer can tell */
    sc = ac->ac_sc;
    ac->ac_flags |= AMR_CMD_BUSY;

    /* get a command slot (freed in amr_done) */
    slot = ac->ac_slot;
    if (sc->amr_busycmd[slot] != NULL)
        panic("amr: slot %d busy?", slot);
    sc->amr_busycmd[slot] = ac;
    atomic_add_int(&sc->amr_busyslots, 1);

    /* Now we have a slot, we can map the command (unmapped in amr_complete). */
    if ((error = amr_mapcmd(ac)) == ENOMEM) {
        /*
         * Memroy resources are short, so free the slot and let this be tried
         * later.
         */
        amr_freeslot(ac);
    }

    return (error);
}

/********************************************************************************
 * Extract one or more completed commands from the controller (sc)
 *
 * Returns nonzero if any commands on the work queue were marked as completed.
 */

int
amr_done(struct amr_softc *sc)
{
    ac_qhead_t          head;
    struct amr_command  *ac;
    struct amr_mailbox  mbox;
    int                 i, idx, result;
    
    debug_called(3);

    /* See if there's anything for us to do */
    result = 0;
    amr_init_qhead(&head);

    /* loop collecting completed commands */
    for (;;) {
        /* poll for a completed command's identifier and status */
        if (sc->amr_get_work(sc, &mbox)) {
            result = 1;
            
            /* iterate over completed commands in this result */
            for (i = 0; i < mbox.mb_nstatus; i++) {
                /* get pointer to busy command */
                idx = mbox.mb_completed[i] - 1;
                ac = sc->amr_busycmd[idx];

                /* really a busy command? */
                if (ac != NULL) {

                    /* pull the command from the busy index */
                    amr_freeslot(ac);
                
                    /* save status for later use */
                    ac->ac_status = mbox.mb_status;
                    amr_enqueue_completed(ac, &head);
                    debug(3, "completed command with status %x", mbox.mb_status);
                } else {
                    device_printf(sc->amr_dev, "bad slot %d completed\n", idx);
                }
            }
        } else
            break;      /* no work */
    }

    /* handle completion and timeouts */
    amr_complete(sc, &head);

    return(result);
}

/********************************************************************************
 * Do completion processing on done commands on (sc)
 */

static void
amr_complete(void *context, ac_qhead_t *head)
{
    struct amr_softc    *sc = (struct amr_softc *)context;
    struct amr_command  *ac;

    debug_called(3);

    /* pull completed commands off the queue */
    for (;;) {
        ac = amr_dequeue_completed(sc, head);
        if (ac == NULL)
            break;

        /* unmap the command's data buffer */
        amr_unmapcmd(ac);

        /* 
         * Is there a completion handler? 
         */
        if (ac->ac_complete != NULL) {
            /* unbusy the command */
            ac->ac_flags &= ~AMR_CMD_BUSY;
            ac->ac_complete(ac);
            
            /* 
             * Is someone sleeping on this one?
             */
        } else {
            lockmgr(&sc->amr_list_lock, LK_EXCLUSIVE);
            ac->ac_flags &= ~AMR_CMD_BUSY;
            if (ac->ac_flags & AMR_CMD_SLEEP) {
                /* unbusy the command */
                wakeup(ac);
            }
            lockmgr(&sc->amr_list_lock, LK_RELEASE);
        }

        if(!sc->amr_busyslots) {
            wakeup(sc);
        }
    }

    lockmgr(&sc->amr_list_lock, LK_EXCLUSIVE);
    sc->amr_state &= ~AMR_STATE_QUEUE_FRZN;
    amr_startio(sc);
    lockmgr(&sc->amr_list_lock, LK_RELEASE);
}

/********************************************************************************
 ********************************************************************************
                                                        Command Buffer Management
 ********************************************************************************
 ********************************************************************************/

/********************************************************************************
 * Get a new command buffer.
 *
 * This may return NULL in low-memory cases.
 *
 * If possible, we recycle a command buffer that's been used before.
 */
struct amr_command *
amr_alloccmd(struct amr_softc *sc)
{
    struct amr_command  *ac;

    debug_called(3);

    ac = amr_dequeue_free(sc);
    if (ac == NULL) {
        sc->amr_state |= AMR_STATE_QUEUE_FRZN;
        return(NULL);
    }

    /* clear out significant fields */
    ac->ac_status = 0;
    bzero(&ac->ac_mailbox, sizeof(struct amr_mailbox));
    ac->ac_flags = 0;
    ac->ac_bio = NULL;
    ac->ac_data = NULL;
    ac->ac_complete = NULL;
    ac->ac_retries = 0;
    ac->ac_tag = NULL;
    ac->ac_datamap = NULL;
    return(ac);
}

/********************************************************************************
 * Release a command buffer for recycling.
 */
void
amr_releasecmd(struct amr_command *ac)
{
    debug_called(3);

    amr_enqueue_free(ac);
}

/********************************************************************************
 * Allocate a new command cluster and initialise it.
 */
static void
amr_alloccmd_cluster(struct amr_softc *sc)
{
    struct amr_command_cluster  *acc;
    struct amr_command          *ac;
    int                         i, nextslot;

    /*
     * If we haven't found the real limit yet, let us have a couple of
     * commands in order to be able to probe.
     */
    if (sc->amr_maxio == 0)
        sc->amr_maxio = 2;

    if (sc->amr_nextslot > sc->amr_maxio)
        return;
    acc = kmalloc(AMR_CMD_CLUSTERSIZE, M_AMR, M_NOWAIT | M_ZERO);
    if (acc != NULL) {
        nextslot = sc->amr_nextslot;
        lockmgr(&sc->amr_list_lock, LK_EXCLUSIVE);
        TAILQ_INSERT_TAIL(&sc->amr_cmd_clusters, acc, acc_link);
        lockmgr(&sc->amr_list_lock, LK_RELEASE);
        for (i = 0; i < AMR_CMD_CLUSTERCOUNT; i++) {
            ac = &acc->acc_command[i];
            ac->ac_sc = sc;
            ac->ac_slot = nextslot;

            /*
             * The SG table for each slot is a fixed size and is assumed to
             * to hold 64-bit s/g objects when the driver is configured to do
             * 64-bit DMA.  32-bit DMA commands still use the same table, but
             * cast down to 32-bit objects.
             */
            if (AMR_IS_SG64(sc)) {
                ac->ac_sgbusaddr = sc->amr_sgbusaddr +
                    (ac->ac_slot * AMR_NSEG * sizeof(struct amr_sg64entry));
                ac->ac_sg.sg64 = sc->amr_sg64table + (ac->ac_slot * AMR_NSEG);
            } else {
                ac->ac_sgbusaddr = sc->amr_sgbusaddr +
                    (ac->ac_slot * AMR_NSEG * sizeof(struct amr_sgentry));
                ac->ac_sg.sg32 = sc->amr_sgtable + (ac->ac_slot * AMR_NSEG);
            }

            ac->ac_ccb = sc->amr_ccb + ac->ac_slot;
            ac->ac_ccb_busaddr = sc->amr_ccb_busaddr +
                (ac->ac_slot * sizeof(union amr_ccb));

            if (bus_dmamap_create(sc->amr_buffer_dmat, 0, &ac->ac_dmamap))
                break;
            if (AMR_IS_SG64(sc) &&
                (bus_dmamap_create(sc->amr_buffer64_dmat, 0,&ac->ac_dma64map)))
                break;
            amr_releasecmd(ac);
            if (++nextslot > sc->amr_maxio)
                break;
        }
        sc->amr_nextslot = nextslot;
    }
}

/********************************************************************************
 * Free a command cluster
 */
static void
amr_freecmd_cluster(struct amr_command_cluster *acc)
{
    struct amr_softc    *sc = acc->acc_command[0].ac_sc;
    int                 i;

    for (i = 0; i < AMR_CMD_CLUSTERCOUNT; i++) {
        if (acc->acc_command[i].ac_sc == NULL)
            break;
        bus_dmamap_destroy(sc->amr_buffer_dmat, acc->acc_command[i].ac_dmamap);
        if (AMR_IS_SG64(sc))
                bus_dmamap_destroy(sc->amr_buffer64_dmat, acc->acc_command[i].ac_dma64map);
    }
    kfree(acc, M_AMR);
}

/********************************************************************************
 ********************************************************************************
                                                         Interface-specific Shims
 ********************************************************************************
 ********************************************************************************/

/********************************************************************************
 * Tell the controller that the mailbox contains a valid command
 */
static int
amr_quartz_submit_command(struct amr_command *ac)
{
    struct amr_softc    *sc = ac->ac_sc;
    static struct timeval lastfail;
    static int          curfail;
    int                 i = 0;

    lockmgr(&sc->amr_hw_lock, LK_EXCLUSIVE);
    while (sc->amr_mailbox->mb_busy && (i++ < 10)) {
        DELAY(1);
        /* This is a no-op read that flushes pending mailbox updates */
        AMR_QGET_ODB(sc);
    }
    if (sc->amr_mailbox->mb_busy) {
        lockmgr(&sc->amr_hw_lock, LK_RELEASE);
        if (ac->ac_retries++ > 1000) {
            if (ppsratecheck(&lastfail, &curfail, 1))
                device_printf(sc->amr_dev, "Too many retries on command %p.  "
                              "Controller is likely dead\n", ac);
            ac->ac_retries = 0;
        }
        return (EBUSY);
    }

    /*
     * Save the slot number so that we can locate this command when complete.
     * Note that ident = 0 seems to be special, so we don't use it.
     */
    ac->ac_mailbox.mb_ident = ac->ac_slot + 1; /* will be coppied into mbox */
    bcopy(&ac->ac_mailbox, (void *)(uintptr_t)(volatile void *)sc->amr_mailbox, 14);
    sc->amr_mailbox->mb_busy = 1;
    sc->amr_mailbox->mb_poll = 0;
    sc->amr_mailbox->mb_ack  = 0;
    sc->amr_mailbox64->sg64_hi = ac->ac_sg64_hi;
    sc->amr_mailbox64->sg64_lo = ac->ac_sg64_lo;

    AMR_QPUT_IDB(sc, sc->amr_mailboxphys | AMR_QIDB_SUBMIT);
    lockmgr(&sc->amr_hw_lock, LK_RELEASE);
    return(0);
}

static int
amr_std_submit_command(struct amr_command *ac)
{
    struct amr_softc    *sc = ac->ac_sc;
    static struct timeval lastfail;
    static int          curfail;

    lockmgr(&sc->amr_hw_lock, LK_EXCLUSIVE);
    if (AMR_SGET_MBSTAT(sc) & AMR_SMBOX_BUSYFLAG) {
        lockmgr(&sc->amr_hw_lock, LK_RELEASE);
        if (ac->ac_retries++ > 1000) {
            if (ppsratecheck(&lastfail, &curfail, 1))
                device_printf(sc->amr_dev, "Too many retries on command %p.  "
                              "Controller is likely dead\n", ac);
            ac->ac_retries = 0;
        }
        return (EBUSY);
    }

    /*
     * Save the slot number so that we can locate this command when complete.
     * Note that ident = 0 seems to be special, so we don't use it.
     */
    ac->ac_mailbox.mb_ident = ac->ac_slot + 1; /* will be coppied into mbox */
    bcopy(&ac->ac_mailbox, (void *)(uintptr_t)(volatile void *)sc->amr_mailbox, 14);
    sc->amr_mailbox->mb_busy = 1;
    sc->amr_mailbox->mb_poll = 0;
    sc->amr_mailbox->mb_ack  = 0;

    AMR_SPOST_COMMAND(sc);
    lockmgr(&sc->amr_hw_lock, LK_RELEASE);
    return(0);
}

/********************************************************************************
 * Claim any work that the controller has completed; acknowledge completion,
 * save details of the completion in (mbsave)
 */
static int
amr_quartz_get_work(struct amr_softc *sc, struct amr_mailbox *mbsave)
{
    int         worked, i;
    u_int32_t   outd;
    u_int8_t    nstatus;
    u_int8_t    completed[46];

    debug_called(3);

    worked = 0;

    /* work waiting for us? */
    if ((outd = AMR_QGET_ODB(sc)) == AMR_QODB_READY) {

        /* acknowledge interrupt */
        AMR_QPUT_ODB(sc, AMR_QODB_READY);

        while ((nstatus = sc->amr_mailbox->mb_nstatus) == 0xff)
            DELAY(1);
        sc->amr_mailbox->mb_nstatus = 0xff;

        /* wait until fw wrote out all completions */
        for (i = 0; i < nstatus; i++) {
            while ((completed[i] = sc->amr_mailbox->mb_completed[i]) == 0xff)
                DELAY(1);
            sc->amr_mailbox->mb_completed[i] = 0xff;
        }

        /* Save information for later processing */
        mbsave->mb_nstatus = nstatus;
        mbsave->mb_status = sc->amr_mailbox->mb_status;
        sc->amr_mailbox->mb_status = 0xff;

        for (i = 0; i < nstatus; i++)
            mbsave->mb_completed[i] = completed[i];

        /* acknowledge that we have the commands */
        AMR_QPUT_IDB(sc, AMR_QIDB_ACK);

#if 0
#ifndef AMR_QUARTZ_GOFASTER
        /*
         * This waits for the controller to notice that we've taken the
         * command from it.  It's very inefficient, and we shouldn't do it,
         * but if we remove this code, we stop completing commands under
         * load.
         *
         * Peter J says we shouldn't do this.  The documentation says we
         * should.  Who is right?
         */
        while(AMR_QGET_IDB(sc) & AMR_QIDB_ACK)
            ;                           /* XXX aiee! what if it dies? */
#endif
#endif

        worked = 1;                     /* got some work */
    }

    return(worked);
}

static int
amr_std_get_work(struct amr_softc *sc, struct amr_mailbox *mbsave)
{
    int         worked;
    u_int8_t    istat;

    debug_called(3);

    worked = 0;

    /* check for valid interrupt status */
    istat = AMR_SGET_ISTAT(sc);
    if ((istat & AMR_SINTR_VALID) != 0) {
        AMR_SPUT_ISTAT(sc, istat);      /* ack interrupt status */

        /* save mailbox, which contains a list of completed commands */
        bcopy((void *)(uintptr_t)(volatile void *)sc->amr_mailbox, mbsave, sizeof(*mbsave));

        AMR_SACK_INTERRUPT(sc);         /* acknowledge we have the mailbox */
        worked = 1;
    }

    return(worked);
}

/********************************************************************************
 * Notify the controller of the mailbox location.
 */
static void
amr_std_attach_mailbox(struct amr_softc *sc)
{

    /* program the mailbox physical address */
    AMR_SBYTE_SET(sc, AMR_SMBOX_0, sc->amr_mailboxphys         & 0xff);
    AMR_SBYTE_SET(sc, AMR_SMBOX_1, (sc->amr_mailboxphys >>  8) & 0xff);
    AMR_SBYTE_SET(sc, AMR_SMBOX_2, (sc->amr_mailboxphys >> 16) & 0xff);
    AMR_SBYTE_SET(sc, AMR_SMBOX_3, (sc->amr_mailboxphys >> 24) & 0xff);
    AMR_SBYTE_SET(sc, AMR_SMBOX_ENABLE, AMR_SMBOX_ADDR);

    /* clear any outstanding interrupt and enable interrupts proper */
    AMR_SACK_INTERRUPT(sc);
    AMR_SENABLE_INTR(sc);
}

#ifdef AMR_BOARD_INIT
/********************************************************************************
 * Initialise the controller
 */
static int
amr_quartz_init(struct amr_softc *sc)
{
    int         status, ostatus;

    device_printf(sc->amr_dev, "initial init status %x\n", AMR_QGET_INITSTATUS(sc));

    AMR_QRESET(sc);

    ostatus = 0xff;
    while ((status = AMR_QGET_INITSTATUS(sc)) != AMR_QINIT_DONE) {
        if (status != ostatus) {
            device_printf(sc->amr_dev, "(%x) %s\n", status, amr_describe_code(amr_table_qinit, status));
            ostatus = status;
        }
        switch (status) {
        case AMR_QINIT_NOMEM:
            return(ENOMEM);

        case AMR_QINIT_SCAN:
            /* XXX we could print channel/target here */
            break;
        }
    }
    return(0);
}

static int
amr_std_init(struct amr_softc *sc)
{
    int         status, ostatus;

    device_printf(sc->amr_dev, "initial init status %x\n", AMR_SGET_INITSTATUS(sc));

    AMR_SRESET(sc);
 
    ostatus = 0xff;
    while ((status = AMR_SGET_INITSTATUS(sc)) != AMR_SINIT_DONE) {
        if (status != ostatus) {
            device_printf(sc->amr_dev, "(%x) %s\n", status, amr_describe_code(amr_table_sinit, status));
            ostatus = status;
        }
        switch (status) {
        case AMR_SINIT_NOMEM:
            return(ENOMEM);

        case AMR_SINIT_INPROG:
            /* XXX we could print channel/target here? */
            break;
        }
    }
    return(0);
}
#endif

/********************************************************************************
 ********************************************************************************
                                                                        Debugging
 ********************************************************************************
 ********************************************************************************/

/********************************************************************************
 * Identify the controller and print some information about it.
 */
static void
amr_describe_controller(struct amr_softc *sc)
{
    struct amr_prodinfo *ap;
    struct amr_enquiry  *ae;
    char                *prod;
    int                 status;

    /*
     * Try to get 40LD product info, which tells us what the card is labelled as.
     */
    if ((ap = amr_enquiry(sc, 2048, AMR_CMD_CONFIG, AMR_CONFIG_PRODUCT_INFO, 0, &status)) != NULL) {
        device_printf(sc->amr_dev, "<LSILogic %.80s> Firmware %.16s, BIOS %.16s, %dMB RAM\n",
                      ap->ap_product, ap->ap_firmware, ap->ap_bios,
                      ap->ap_memsize);

        kfree(ap, M_AMR);
        return;
    }

    /*
     * Try 8LD extended ENQUIRY to get controller signature, and use lookup table.
     */
    if ((ae = (struct amr_enquiry *)amr_enquiry(sc, 2048, AMR_CMD_EXT_ENQUIRY2, 0, 0, &status)) != NULL) {
        prod = amr_describe_code(amr_table_adaptertype, ae->ae_signature);

    } else if ((ae = (struct amr_enquiry *)amr_enquiry(sc, 2048, AMR_CMD_ENQUIRY, 0, 0, &status)) != NULL) {

        /*
         * Try to work it out based on the PCI signatures.
         */
        switch (pci_get_device(sc->amr_dev)) {
        case 0x9010:
            prod = "Series 428";
            break;
        case 0x9060:
            prod = "Series 434";
            break;
        default:
            prod = "unknown controller";
            break;
        }
    } else {
        device_printf(sc->amr_dev, "<unsupported controller>\n");
        return;
    }

    /*
     * HP NetRaid controllers have a special encoding of the firmware and
     * BIOS versions. The AMI version seems to have it as strings whereas
     * the HP version does it with a leading uppercase character and two
     * binary numbers.
     */
     
    if(ae->ae_adapter.aa_firmware[2] >= 'A' &&
       ae->ae_adapter.aa_firmware[2] <= 'Z' &&
       ae->ae_adapter.aa_firmware[1] <  ' ' &&
       ae->ae_adapter.aa_firmware[0] <  ' ' &&
       ae->ae_adapter.aa_bios[2] >= 'A'     &&
       ae->ae_adapter.aa_bios[2] <= 'Z'     &&
       ae->ae_adapter.aa_bios[1] <  ' '     &&
       ae->ae_adapter.aa_bios[0] <  ' ') {

        /* this looks like we have an HP NetRaid version of the MegaRaid */

        if(ae->ae_signature == AMR_SIG_438) {
                /* the AMI 438 is a NetRaid 3si in HP-land */
                prod = "HP NetRaid 3si";
        }
        
        device_printf(sc->amr_dev, "<%s> Firmware %c.%02d.%02d, BIOS %c.%02d.%02d, %dMB RAM\n",
                      prod, ae->ae_adapter.aa_firmware[2],
                      ae->ae_adapter.aa_firmware[1],
                      ae->ae_adapter.aa_firmware[0],
                      ae->ae_adapter.aa_bios[2],
                      ae->ae_adapter.aa_bios[1],
                      ae->ae_adapter.aa_bios[0],
                      ae->ae_adapter.aa_memorysize);            
    } else {
        device_printf(sc->amr_dev, "<%s> Firmware %.4s, BIOS %.4s, %dMB RAM\n", 
                      prod, ae->ae_adapter.aa_firmware, ae->ae_adapter.aa_bios,
                      ae->ae_adapter.aa_memorysize);
    }           
    kfree(ae, M_AMR);
}

int
amr_dump_blocks(struct amr_softc *sc, int unit, u_int32_t lba, void *data, int blks)
{
    struct amr_command  *ac;
    int                 error = EIO;

    debug_called(1);

    sc->amr_state |= AMR_STATE_INTEN;

    /* get ourselves a command buffer */
    if ((ac = amr_alloccmd(sc)) == NULL)
        goto out;
    /* set command flags */
    ac->ac_flags |= AMR_CMD_PRIORITY | AMR_CMD_DATAOUT;
    
    /* point the command at our data */
    ac->ac_data = data;
    ac->ac_length = blks * AMR_BLKSIZE;
    
    /* build the command proper */
    ac->ac_mailbox.mb_command   = AMR_CMD_LWRITE;
    ac->ac_mailbox.mb_blkcount  = blks;
    ac->ac_mailbox.mb_lba       = lba;
    ac->ac_mailbox.mb_drive     = unit;

    /* can't assume that interrupts are going to work here, so play it safe */
    if (sc->amr_poll_command(ac))
        goto out;
    error = ac->ac_status;
    
 out:
    if (ac != NULL)
        amr_releasecmd(ac);

    sc->amr_state &= ~AMR_STATE_INTEN;
    return (error);
}



#ifdef AMR_DEBUG
/********************************************************************************
 * Print the command (ac) in human-readable format
 */
#if 0
static void
amr_printcommand(struct amr_command *ac)
{
    struct amr_softc    *sc = ac->ac_sc;
    struct amr_sgentry  *sg;
    int                 i;
    
    device_printf(sc->amr_dev, "cmd %x  ident %d  drive %d\n",
                  ac->ac_mailbox.mb_command, ac->ac_mailbox.mb_ident, ac->ac_mailbox.mb_drive);
    device_printf(sc->amr_dev, "blkcount %d  lba %d\n", 
                  ac->ac_mailbox.mb_blkcount, ac->ac_mailbox.mb_lba);
    device_printf(sc->amr_dev, "virtaddr %p  length %lu\n", ac->ac_data, (unsigned long)ac->ac_length);
    device_printf(sc->amr_dev, "sg physaddr %08x  nsg %d\n",
                  ac->ac_mailbox.mb_physaddr, ac->ac_mailbox.mb_nsgelem);
    device_printf(sc->amr_dev, "ccb %p  bio %p\n", ac->ac_ccb_data, ac->ac_bio);

    /* get base address of s/g table */
    sg = sc->amr_sgtable + (ac->ac_slot * AMR_NSEG);
    for (i = 0; i < ac->ac_mailbox.mb_nsgelem; i++, sg++)
        device_printf(sc->amr_dev, "  %x/%d\n", sg->sg_addr, sg->sg_count);
}
#endif
#endif