/*      $NetBSD: esp_sbus.c,v 1.57 2022/03/28 12:38:58 riastradh Exp $  */

/*-
 * Copyright (c) 1997, 1998 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Charles M. Hannum; Jason R. Thorpe of the Numerical Aerospace
 * Simulation Facility, NASA Ames Research Center; Paul Kranenburg.
 *
 * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: esp_sbus.c,v 1.57 2022/03/28 12:38:58 riastradh Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/device_impl.h>    /* XXX autoconf abuse */
#include <sys/buf.h>
#include <sys/malloc.h>

#include <dev/scsipi/scsi_all.h>
#include <dev/scsipi/scsipi_all.h>
#include <dev/scsipi/scsiconf.h>
#include <dev/scsipi/scsi_message.h>

#include <sys/bus.h>
#include <sys/intr.h>
#include <machine/autoconf.h>

#include <dev/ic/lsi64854reg.h>
#include <dev/ic/lsi64854var.h>

#include <dev/ic/ncr53c9xreg.h>
#include <dev/ic/ncr53c9xvar.h>

#include <dev/sbus/sbusvar.h>

#include "opt_ddb.h"

/* #define ESP_SBUS_DEBUG */

struct esp_softc {
        struct ncr53c9x_softc sc_ncr53c9x;      /* glue to MI code */

        bus_space_tag_t sc_bustag;
        bus_dma_tag_t   sc_dmatag;

        bus_space_handle_t sc_reg;              /* the registers */
        struct lsi64854_softc *sc_dma;          /* pointer to my dma */

        int     sc_pri;                         /* SBUS priority */
};

int     espmatch_sbus(device_t, cfdata_t, void *);
void    espattach_sbus(device_t, device_t, void *);
void    espattach_dma(device_t, device_t, void *);

static void     espattach(struct esp_softc *, struct ncr53c9x_glue *);

CFATTACH_DECL_NEW(esp_sbus, sizeof(struct esp_softc),
    espmatch_sbus, espattach_sbus, NULL, NULL);

CFATTACH_DECL_NEW(esp_dma, sizeof(struct esp_softc),
    espmatch_sbus, espattach_dma, NULL, NULL);

/*
 * Functions and the switch for the MI code.
 */
static uint8_t  esp_read_reg(struct ncr53c9x_softc *, int);
static void     esp_write_reg(struct ncr53c9x_softc *, int, uint8_t);
static uint8_t  esp_rdreg1(struct ncr53c9x_softc *, int);
static void     esp_wrreg1(struct ncr53c9x_softc *, int, uint8_t);
static int      esp_dma_isintr(struct ncr53c9x_softc *);
static void     esp_dma_reset(struct ncr53c9x_softc *);
static int      esp_dma_intr(struct ncr53c9x_softc *);
static int      esp_dma_setup(struct ncr53c9x_softc *, uint8_t **,
                                    size_t *, int, size_t *);
static void     esp_dma_go(struct ncr53c9x_softc *);
static void     esp_dma_stop(struct ncr53c9x_softc *);
static int      esp_dma_isactive(struct ncr53c9x_softc *);

#ifdef DDB
static void     esp_init_ddb_cmds(void);
#endif

static struct ncr53c9x_glue esp_sbus_glue = {
        esp_read_reg,
        esp_write_reg,
        esp_dma_isintr,
        esp_dma_reset,
        esp_dma_intr,
        esp_dma_setup,
        esp_dma_go,
        esp_dma_stop,
        esp_dma_isactive,
        NULL,                   /* gl_clear_latched_intr */
};

static struct ncr53c9x_glue esp_sbus_glue1 = {
        esp_rdreg1,
        esp_wrreg1,
        esp_dma_isintr,
        esp_dma_reset,
        esp_dma_intr,
        esp_dma_setup,
        esp_dma_go,
        esp_dma_stop,
        esp_dma_isactive,
        NULL,                   /* gl_clear_latched_intr */
};

int
espmatch_sbus(device_t parent, cfdata_t cf, void *aux)
{
        int rv;
        struct sbus_attach_args *sa = aux;

        if (strcmp("SUNW,fas", sa->sa_name) == 0)
                return 1;

        rv = (strcmp(cf->cf_name, sa->sa_name) == 0 ||
            strcmp("ptscII", sa->sa_name) == 0);
        return rv;
}

void
espattach_sbus(device_t parent, device_t self, void *aux)
{
        struct esp_softc *esc = device_private(self);
        struct ncr53c9x_softc *sc = &esc->sc_ncr53c9x;
        struct sbus_softc *sbsc = device_private(parent);
        struct sbus_attach_args *sa = aux;
        struct lsi64854_softc *lsc;
        device_t dma_dev;
        int burst, sbusburst;

        sc->sc_dev = self;

#ifdef DDB
        esp_init_ddb_cmds();
#endif

        esc->sc_bustag = sa->sa_bustag;
        esc->sc_dmatag = sa->sa_dmatag;

        sc->sc_id = prom_getpropint(sa->sa_node, "initiator-id", 7);
        sc->sc_freq = prom_getpropint(sa->sa_node, "clock-frequency", -1);
        if (sc->sc_freq < 0)
                sc->sc_freq = sbsc->sc_clockfreq;

#ifdef ESP_SBUS_DEBUG
        aprint_normal("\n");
        aprint_normal_dev(self, "%s: sc_id %d, freq %d\n",
            __func__, sc->sc_id, sc->sc_freq);
        aprint_normal("%s", device_xname(self));
#endif

        if (strcmp("SUNW,fas", sa->sa_name) == 0) {

                /*
                 * fas has 2 register spaces: dma(lsi64854) and
                 *                            SCSI core (ncr53c9x)
                 */
                if (sa->sa_nreg != 2) {
                        aprint_error(": %d register spaces\n", sa->sa_nreg);
                        return;
                }

                /*
                 * allocate space for dma, in SUNW,fas there are no separate
                 * dma device
                 */
                lsc = malloc(sizeof(struct lsi64854_softc), M_DEVBUF, M_WAITOK);
                lsc->sc_dev = malloc(sizeof(struct device), M_DEVBUF,
                    M_WAITOK | M_ZERO);
                esc->sc_dma = lsc;

                lsc->sc_bustag = sa->sa_bustag;
                lsc->sc_dmatag = sa->sa_dmatag;

                strlcpy(lsc->sc_dev->dv_xname, device_xname(sc->sc_dev),
                    sizeof(lsc->sc_dev->dv_xname));

                /* Map dma registers */
                if (sa->sa_npromvaddrs) {
                        sbus_promaddr_to_handle(sa->sa_bustag,
                            sa->sa_promvaddrs[0], &lsc->sc_regs);
                } else {
                        if (sbus_bus_map(sa->sa_bustag,
                            sa->sa_reg[0].oa_space,
                            sa->sa_reg[0].oa_base,
                            sa->sa_reg[0].oa_size,
                            0, &lsc->sc_regs) != 0) {
                                aprint_error(": cannot map dma registers\n");
                                return;
                        }
                }

                /*
                 * XXX is this common(from bpp.c), the same in dma_sbus...etc.
                 *
                 * Get transfer burst size from PROM and plug it into the
                 * controller registers. This is needed on the Sun4m; do
                 * others need it too?
                 */
                sbusburst = sbsc->sc_burst;
                if (sbusburst == 0)
                        sbusburst = SBUS_BURST_32 - 1; /* 1->16 */

                burst = prom_getpropint(sa->sa_node, "burst-sizes", -1);

#if ESP_SBUS_DEBUG
                aprint_normal("%s: burst 0x%x, sbus 0x%x\n",
                    __func__, burst, sbusburst);
                aprint_normal("%s", device_xname(self));
#endif

                if (burst == -1)
                        /* take SBus burst sizes */
                        burst = sbusburst;

                /* Clamp at parent's burst sizes */
                burst &= sbusburst;
                lsc->sc_burst = (burst & SBUS_BURST_32) ? 32 :
                    (burst & SBUS_BURST_16) ? 16 : 0;

                lsc->sc_channel = L64854_CHANNEL_SCSI;
                lsc->sc_client = sc;

                lsi64854_attach(lsc);

                /*
                 * map SCSI core registers
                 */
                if (sa->sa_npromvaddrs > 1) {
                        sbus_promaddr_to_handle(sa->sa_bustag,
                            sa->sa_promvaddrs[1], &esc->sc_reg);
                } else {
                        if (sbus_bus_map(sa->sa_bustag,
                            sa->sa_reg[1].oa_space,
                            sa->sa_reg[1].oa_base,
                            sa->sa_reg[1].oa_size,
                            0, &esc->sc_reg) != 0) {
                                aprint_error(": cannot map "
                                    "scsi core registers\n");
                                return;
                        }
                }

                if (sa->sa_nintr == 0) {
                        aprint_error(": no interrupt property\n");
                        return;
                }

                esc->sc_pri = sa->sa_pri;

                espattach(esc, &esp_sbus_glue);

                return;
        }

        /*
         * Find the DMA by poking around the dma device structures
         *
         * What happens here is that if the dma driver has not been
         * configured, then this returns a NULL pointer. Then when the
         * dma actually gets configured, it does the opposing test, and
         * if the sc->sc_esp field in its softc is NULL, then tries to
         * find the matching esp driver.
         */
        dma_dev = device_find_by_driver_unit("dma", device_unit(self));
        if (dma_dev == NULL) {
                aprint_error(": no corresponding DMA device\n");
                return;
        }
        esc->sc_dma = device_private(dma_dev);
        esc->sc_dma->sc_client = sc;

        /*
         * The `ESC' DMA chip must be reset before we can access
         * the esp registers.
         */
        if (esc->sc_dma->sc_rev == DMAREV_ESC)
                DMA_RESET(esc->sc_dma);

        /*
         * Map my registers in, if they aren't already in virtual
         * address space.
         */
        if (sa->sa_npromvaddrs) {
                sbus_promaddr_to_handle(sa->sa_bustag,
                    sa->sa_promvaddrs[0], &esc->sc_reg);
        } else {
                if (sbus_bus_map(sa->sa_bustag,
                    sa->sa_slot, sa->sa_offset, sa->sa_size,
                    0, &esc->sc_reg) != 0) {
                        aprint_error(": cannot map registers\n");
                        return;
                }
        }

        if (sa->sa_nintr == 0) {
                /*
                 * No interrupt properties: we quit; this might
                 * happen on e.g. a Sparc X terminal.
                 */
                aprint_error(": no interrupt property\n");
                return;
        }

        esc->sc_pri = sa->sa_pri;

        if (strcmp("ptscII", sa->sa_name) == 0) {
                espattach(esc, &esp_sbus_glue1);
        } else {
                espattach(esc, &esp_sbus_glue);
        }
}

void
espattach_dma(device_t parent, device_t self, void *aux)
{
        struct esp_softc *esc = device_private(self);
        struct ncr53c9x_softc *sc = &esc->sc_ncr53c9x;
        struct sbus_attach_args *sa = aux;

        if (strcmp("ptscII", sa->sa_name) == 0) {
                return;
        }

        sc->sc_dev = self;

        esc->sc_bustag = sa->sa_bustag;
        esc->sc_dmatag = sa->sa_dmatag;

        sc->sc_id = prom_getpropint(sa->sa_node, "initiator-id", 7);
        sc->sc_freq = prom_getpropint(sa->sa_node, "clock-frequency", -1);

        esc->sc_dma = device_private(parent);
        esc->sc_dma->sc_client = sc;

        /*
         * Map my registers in, if they aren't already in virtual
         * address space.
         */
        if (sa->sa_npromvaddrs) {
                sbus_promaddr_to_handle(sa->sa_bustag,
                    sa->sa_promvaddrs[0], &esc->sc_reg);
        } else {
                if (sbus_bus_map(sa->sa_bustag,
                    sa->sa_slot, sa->sa_offset, sa->sa_size,
                    0, &esc->sc_reg) != 0) {
                        aprint_error(": cannot map registers\n");
                        return;
                }
        }

        if (sa->sa_nintr == 0) {
                /*
                 * No interrupt properties: we quit; this might
                 * happen on e.g. a Sparc X terminal.
                 */
                aprint_error(": no interrupt property\n");
                return;
        }

        esc->sc_pri = sa->sa_pri;

        espattach(esc, &esp_sbus_glue);
}


/*
 * Attach this instance, and then all the sub-devices
 */
void
espattach(struct esp_softc *esc, struct ncr53c9x_glue *gluep)
{
        struct ncr53c9x_softc *sc = &esc->sc_ncr53c9x;
        unsigned int uid = 0;

        /*
         * Set up glue for MI code early; we use some of it here.
         */
        sc->sc_glue = gluep;

        /* gimme MHz */
        sc->sc_freq /= 1000000;

        /*
         * XXX More of this should be in ncr53c9x_attach(), but
         * XXX should we really poke around the chip that much in
         * XXX the MI code?  Think about this more...
         */

        /*
         * It is necessary to try to load the 2nd config register here,
         * to find out what rev the esp chip is, else the ncr53c9x_reset
         * will not set up the defaults correctly.
         */
        sc->sc_cfg1 = sc->sc_id | NCRCFG1_PARENB;
        sc->sc_cfg2 = NCRCFG2_SCSI2 | NCRCFG2_RPE;
        sc->sc_cfg3 = NCRCFG3_CDB;
        NCR_WRITE_REG(sc, NCR_CFG2, sc->sc_cfg2);

        if ((NCR_READ_REG(sc, NCR_CFG2) & ~NCRCFG2_RSVD) !=
            (NCRCFG2_SCSI2 | NCRCFG2_RPE)) {
                sc->sc_rev = NCR_VARIANT_ESP100;
        } else {
                sc->sc_cfg2 = NCRCFG2_SCSI2;
                NCR_WRITE_REG(sc, NCR_CFG2, sc->sc_cfg2);
                sc->sc_cfg3 = 0;
                NCR_WRITE_REG(sc, NCR_CFG3, sc->sc_cfg3);
                sc->sc_cfg3 = (NCRCFG3_CDB | NCRCFG3_FCLK);
                NCR_WRITE_REG(sc, NCR_CFG3, sc->sc_cfg3);
                if (NCR_READ_REG(sc, NCR_CFG3) !=
                    (NCRCFG3_CDB | NCRCFG3_FCLK)) {
                        sc->sc_rev = NCR_VARIANT_ESP100A;
                } else {
                        /* NCRCFG2_FE enables > 64K transfers */
                        sc->sc_cfg2 |= NCRCFG2_FE;
                        sc->sc_cfg3 = 0;
                        NCR_WRITE_REG(sc, NCR_CFG3, sc->sc_cfg3);
                        sc->sc_rev = NCR_VARIANT_ESP200;

                        /*
                         * XXX spec says it's valid after power up or
                         * chip reset
                         */
                        uid = NCR_READ_REG(sc, NCR_UID);
                        if (((uid & 0xf8) >> 3) == 0x0a) /* XXX */
                                sc->sc_rev = NCR_VARIANT_FAS366;
                }
        }

#ifdef ESP_SBUS_DEBUG
        aprint_debug("%s: revision %d, uid 0x%x\n", __func__, sc->sc_rev, uid);
        aprint_normal("%s", device_xname(sc->sc_dev));
#endif

        /*
         * XXX minsync and maxxfer _should_ be set up in MI code,
         * XXX but it appears to have some dependency on what sort
         * XXX of DMA we're hooked up to, etc.
         */

        /*
         * This is the value used to start sync negotiations
         * Note that the NCR register "SYNCTP" is programmed
         * in "clocks per byte", and has a minimum value of 4.
         * The SCSI period used in negotiation is one-fourth
         * of the time (in nanoseconds) needed to transfer one byte.
         * Since the chip's clock is given in MHz, we have the following
         * formula: 4 * period = (1000 / freq) * 4
         */
        sc->sc_minsync = 1000 / sc->sc_freq;

        /*
         * Alas, we must now modify the value a bit, because it's
         * only valid when can switch on FASTCLK and FASTSCSI bits
         * in config register 3...
         */
        switch (sc->sc_rev) {
        case NCR_VARIANT_ESP100:
                sc->sc_maxxfer = 64 * 1024;
                sc->sc_minsync = 0;     /* No synch on old chip? */
                break;

        case NCR_VARIANT_ESP100A:
                sc->sc_maxxfer = 64 * 1024;
                /* Min clocks/byte is 5 */
                sc->sc_minsync = ncr53c9x_cpb2stp(sc, 5);
                break;

        case NCR_VARIANT_ESP200:
        case NCR_VARIANT_FAS366:
                sc->sc_maxxfer = 16 * 1024 * 1024;
                /* XXX - do actually set FAST* bits */
                break;
        }

        /* Establish interrupt channel */
        bus_intr_establish(esc->sc_bustag, esc->sc_pri, IPL_BIO,
            ncr53c9x_intr, sc);

        /* register interrupt stats */
        evcnt_attach_dynamic(&sc->sc_intrcnt, EVCNT_TYPE_INTR, NULL,
            device_xname(sc->sc_dev), "intr");

        /* Turn on target selection using the `dma' method */
        if (sc->sc_rev != NCR_VARIANT_FAS366)
                sc->sc_features |= NCR_F_DMASELECT;

        /* Do the common parts of attachment. */
        sc->sc_adapter.adapt_minphys = minphys;
        sc->sc_adapter.adapt_request = ncr53c9x_scsipi_request;
        ncr53c9x_attach(sc);
}

/*
 * Glue functions.
 */

#ifdef ESP_SBUS_DEBUG
int esp_sbus_debug = 0;

static struct {
        char *r_name;
        int   r_flag;
} esp__read_regnames [] = {
        { "TCL", 0},                    /* 0/00 */
        { "TCM", 0},                    /* 1/04 */
        { "FIFO", 0},                   /* 2/08 */
        { "CMD", 0},                    /* 3/0c */
        { "STAT", 0},                   /* 4/10 */
        { "INTR", 0},                   /* 5/14 */
        { "STEP", 0},                   /* 6/18 */
        { "FFLAGS", 1},                 /* 7/1c */
        { "CFG1", 1},                   /* 8/20 */
        { "STAT2", 0},                  /* 9/24 */
        { "CFG4", 1},                   /* a/28 */
        { "CFG2", 1},                   /* b/2c */
        { "CFG3", 1},                   /* c/30 */
        { "-none", 1},                  /* d/34 */
        { "TCH", 1},                    /* e/38 */
        { "TCX", 1},                    /* f/3c */
};

static struct {
        char *r_name;
        int   r_flag;
} esp__write_regnames[] = {
        { "TCL", 1},                    /* 0/00 */
        { "TCM", 1},                    /* 1/04 */
        { "FIFO", 0},                   /* 2/08 */
        { "CMD", 0},                    /* 3/0c */
        { "SELID", 1},                  /* 4/10 */
        { "TIMEOUT", 1},                /* 5/14 */
        { "SYNCTP", 1},                 /* 6/18 */
        { "SYNCOFF", 1},                /* 7/1c */
        { "CFG1", 1},                   /* 8/20 */
        { "CCF", 1},                    /* 9/24 */
        { "TEST", 1},                   /* a/28 */
        { "CFG2", 1},                   /* b/2c */
        { "CFG3", 1},                   /* c/30 */
        { "-none", 1},                  /* d/34 */
        { "TCH", 1},                    /* e/38 */
        { "TCX", 1},                    /* f/3c */
};
#endif

uint8_t
esp_read_reg(struct ncr53c9x_softc *sc, int reg)
{
        struct esp_softc *esc = (struct esp_softc *)sc;
        uint8_t v;

        v = bus_space_read_1(esc->sc_bustag, esc->sc_reg, reg * 4);
#ifdef ESP_SBUS_DEBUG
        if (esp_sbus_debug && (reg < 0x10) && esp__read_regnames[reg].r_flag)
                printf("RD:%x <%s> %x\n", reg * 4,
                    ((unsigned int)reg < 0x10) ?
                    esp__read_regnames[reg].r_name : "<***>", v);
#endif
        return v;
}

void
esp_write_reg(struct ncr53c9x_softc *sc, int reg, uint8_t v)
{
        struct esp_softc *esc = (struct esp_softc *)sc;

#ifdef ESP_SBUS_DEBUG
        if (esp_sbus_debug && (reg < 0x10) && esp__write_regnames[reg].r_flag)
                printf("WR:%x <%s> %x\n", reg * 4,
                    ((unsigned int)reg < 0x10) ?
                    esp__write_regnames[reg].r_name : "<***>", v);
#endif
        bus_space_write_1(esc->sc_bustag, esc->sc_reg, reg * 4, v);
}

uint8_t
esp_rdreg1(struct ncr53c9x_softc *sc, int reg)
{
        struct esp_softc *esc = (struct esp_softc *)sc;

        return bus_space_read_1(esc->sc_bustag, esc->sc_reg, reg);
}

void
esp_wrreg1(struct ncr53c9x_softc *sc, int reg, uint8_t v)
{
        struct esp_softc *esc = (struct esp_softc *)sc;

        bus_space_write_1(esc->sc_bustag, esc->sc_reg, reg, v);
}

int
esp_dma_isintr(struct ncr53c9x_softc *sc)
{
        struct esp_softc *esc = (struct esp_softc *)sc;

        return DMA_ISINTR(esc->sc_dma);
}

void
esp_dma_reset(struct ncr53c9x_softc *sc)
{
        struct esp_softc *esc = (struct esp_softc *)sc;

        DMA_RESET(esc->sc_dma);
}

int
esp_dma_intr(struct ncr53c9x_softc *sc)
{
        struct esp_softc *esc = (struct esp_softc *)sc;

        return DMA_INTR(esc->sc_dma);
}

int
esp_dma_setup(struct ncr53c9x_softc *sc, uint8_t **addr, size_t *len,
    int datain, size_t *dmasize)
{
        struct esp_softc *esc = (struct esp_softc *)sc;

        return DMA_SETUP(esc->sc_dma, addr, len, datain, dmasize);
}

void
esp_dma_go(struct ncr53c9x_softc *sc)
{
        struct esp_softc *esc = (struct esp_softc *)sc;

        DMA_GO(esc->sc_dma);
}

void
esp_dma_stop(struct ncr53c9x_softc *sc)
{
        struct esp_softc *esc = (struct esp_softc *)sc;
        uint32_t csr;

        csr = L64854_GCSR(esc->sc_dma);
        csr &= ~D_EN_DMA;
        L64854_SCSR(esc->sc_dma, csr);
}

int
esp_dma_isactive(struct ncr53c9x_softc *sc)
{
        struct esp_softc *esc = (struct esp_softc *)sc;

        return DMA_ISACTIVE(esc->sc_dma);
}

#ifdef DDB
#include <machine/db_machdep.h>
#include <ddb/db_output.h>
#include <ddb/db_command.h>

void db_esp(db_expr_t, bool, db_expr_t, const char*);

const struct db_command db_esp_command_table[] = {
        { DDB_ADD_CMD("esp",    db_esp, 0, 
          "display status of all esp SCSI controllers and their devices",
          NULL, NULL) },
        { DDB_END_CMD },
};

static void
esp_init_ddb_cmds(void)
{
        static int db_cmds_initialized = 0;

        if (db_cmds_initialized)
                return;
        db_cmds_initialized = 1;
        (void)db_register_tbl(DDB_MACH_CMD, db_esp_command_table);
}

void
db_esp(db_expr_t addr, bool have_addr, db_expr_t count, const char *modif)
{
        device_t dv;
        struct ncr53c9x_softc *sc;
        struct ncr53c9x_ecb *ecb;
        struct ncr53c9x_linfo *li;
        int u, t, i;

        for (u = 0; u < 10; u++) {
                dv = device_find_by_driver_unit("esp", u);
                if (dv == NULL)
                        continue;
                sc = device_private(dv);

                db_printf("%s: nexus %p phase %x prev %x"
                    " dp %p dleft %lx ify %x\n", device_xname(dv),
                    sc->sc_nexus, sc->sc_phase, sc->sc_prevphase,
                      sc->sc_dp, sc->sc_dleft, sc->sc_msgify);
                db_printf("\tmsgout %x msgpriq %x msgin %x:%x:%x:%x:%x\n",
                     sc->sc_msgout, sc->sc_msgpriq, sc->sc_imess[0],
                     sc->sc_imess[1], sc->sc_imess[2], sc->sc_imess[3],
                     sc->sc_imess[0]);
                db_printf("ready: ");
                for (ecb = TAILQ_FIRST(&sc->ready_list); ecb != NULL;
                    ecb = TAILQ_NEXT(ecb, chain)) {
                        db_printf("ecb %p ", ecb);
                        if (ecb == TAILQ_NEXT(ecb, chain)) {
                                db_printf("\nWARNING: tailq loop on ecb %p",
                                    ecb);
                                break;
                        }
                }
                db_printf("\n");

                for (t = 0; t < sc->sc_ntarg; t++) {
                        LIST_FOREACH(li, &sc->sc_tinfo[t].luns, link) {
                                db_printf("t%d lun %d untagged %p"
                                    " busy %d used %x\n",
                                    t, (int)li->lun, li->untagged, li->busy,
                                    li->used);
                                for (i = 0; i < 256; i++) {
                                        ecb = li->queued[i];
                                        if (ecb != NULL) {
                                                db_printf("ecb %p tag %x\n",
                                                    ecb, i);
                                        }
                                }
                        }
                }
        }
}
#endif