/*      $NetBSD: osiop.c,v 1.43 2021/08/07 16:19:12 thorpej Exp $       */

/*-
 * Copyright (c) 2001 Izumi Tsutsui.  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 ``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 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) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Van Jacobson of Lawrence Berkeley Laboratory.
 *
 * 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. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 *
 *      @(#)siop.c      7.5 (Berkeley) 5/4/91
 */

/*
 * Copyright (c) 1994 Michael L. Hitch
 *
 * This code is derived from software contributed to Berkeley by
 * Van Jacobson of Lawrence Berkeley Laboratory.
 *
 * 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 ``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 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.
 *
 *      @(#)siop.c      7.5 (Berkeley) 5/4/91
 */

/*
 * MI NCR53C710 scsi adaptor driver; based on arch/amiga/dev/siop.c:
 *      NetBSD: siop.c,v 1.43 1999/09/30 22:59:53 thorpej Exp
 *
 * bus_space/bus_dma'fied by Izumi Tsutsui <tsutsui@NetBSD.org>
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: osiop.c,v 1.43 2021/08/07 16:19:12 thorpej Exp $");

/* #define OSIOP_DEBUG */

#include "opt_ddb.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/malloc.h>
#include <sys/buf.h>
#include <sys/kernel.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/cpu.h>
#include <sys/bus.h>

#include <dev/ic/osiopreg.h>
#include <dev/ic/osiopvar.h>

/* 53C710 script */
#include <dev/microcode/siop/osiop.out>

static void osiop_minphys(struct buf *);
static void osiop_scsipi_request(struct scsipi_channel *, scsipi_adapter_req_t,
    void *);
static void osiop_poll(struct osiop_softc *, struct osiop_acb *);
static void osiop_sched(struct osiop_softc *);
static void osiop_scsidone(struct osiop_acb *, int);
static void osiop_abort(struct osiop_softc *, const char *);
static void osiop_init(struct osiop_softc *);
static void osiop_reset(struct osiop_softc *);
static void osiop_resetbus(struct osiop_softc *);
static void osiop_start(struct osiop_softc *);
static int osiop_checkintr(struct osiop_softc *, uint8_t, uint8_t, uint8_t,
    int *);
static void osiop_select(struct osiop_softc *);
static void osiop_update_xfer_mode(struct osiop_softc *, int);
static void scsi_period_to_osiop(struct osiop_softc *, int);
static void osiop_timeout(void *);

int osiop_reset_delay = 250;    /* delay after reset, in milliseconds */

#ifdef OSIOP_DEBUG
#define DEBUG_DMA       0x01
#define DEBUG_INT       0x02
#define DEBUG_PHASE     0x04
#define DEBUG_UNEXCEPT  0x08
#define DEBUG_DISC      0x10
#define DEBUG_CMD       0x20
#define DEBUG_ALL       0xff
int osiop_debug = 0; /*DEBUG_ALL;*/

int osiopsync_debug = 0;
int osiopdma_hits = 1;
int osiopstarts = 0;
int osiopints = 0;
int osiopphmm = 0;
int osiop_trix = 0;
#define OSIOP_TRACE_SIZE        128
#define OSIOP_TRACE(a,b,c,d)    do {                            \
        osiop_trbuf[osiop_trix + 0] = (a);                      \
        osiop_trbuf[osiop_trix + 1] = (b);                      \
        osiop_trbuf[osiop_trix + 2] = (c);                      \
        osiop_trbuf[osiop_trix + 3] = (d);                      \
        osiop_trix = (osiop_trix + 4) & (OSIOP_TRACE_SIZE - 1); \
} while (0)
uint8_t osiop_trbuf[OSIOP_TRACE_SIZE];
void osiop_dump_trace(void);
void osiop_dump_acb(struct osiop_acb *);
void osiop_dump(struct osiop_softc *);
#else
#define OSIOP_TRACE(a,b,c,d)
#endif

void
osiop_attach(struct osiop_softc *sc)
{
        struct osiop_acb *acb;
        bus_dma_segment_t seg;
        int nseg;
        int i, err;

        /*
         * Allocate and map DMA-safe memory for the script.
         */
        err = bus_dmamem_alloc(sc->sc_dmat, PAGE_SIZE, PAGE_SIZE, 0,
            &seg, 1, &nseg, BUS_DMA_NOWAIT);
        if (err) {
                aprint_error(": failed to allocate script memory, err=%d\n",
                    err);
                return;
        }
        err = bus_dmamem_map(sc->sc_dmat, &seg, nseg, PAGE_SIZE,
            (void **)&sc->sc_script, BUS_DMA_NOWAIT | BUS_DMA_COHERENT);
        if (err) {
                aprint_error(": failed to map script memory, err=%d\n", err);
                return;
        }
        err = bus_dmamap_create(sc->sc_dmat, PAGE_SIZE, 1, PAGE_SIZE, 0,
            BUS_DMA_NOWAIT, &sc->sc_scrdma);
        if (err) {
                aprint_error(": failed to create script map, err=%d\n", err);
                return;
        }
        err = bus_dmamap_load(sc->sc_dmat, sc->sc_scrdma,
            sc->sc_script, PAGE_SIZE, NULL, BUS_DMA_NOWAIT);
        if (err) {
                aprint_error(": failed to load script map, err=%d\n", err);
                return;
        }

        /*
         * Copy and sync script
         */
        memcpy(sc->sc_script, osiop_script, sizeof(osiop_script));
        bus_dmamap_sync(sc->sc_dmat, sc->sc_scrdma, 0, sizeof(osiop_script),
            BUS_DMASYNC_PREWRITE);

        /*
         * Allocate and map DMA-safe memory for the script data structure.
         */
        err = bus_dmamem_alloc(sc->sc_dmat,
            sizeof(struct osiop_ds) * OSIOP_NACB, PAGE_SIZE, 0,
            &seg, 1, &nseg, BUS_DMA_NOWAIT);
        if (err) {
                aprint_error(": failed to allocate ds memory, err=%d\n", err);
                return;
        }
        err = bus_dmamem_map(sc->sc_dmat, &seg, nseg,
            sizeof(struct osiop_ds) * OSIOP_NACB, (void **)&sc->sc_ds,
            BUS_DMA_NOWAIT | BUS_DMA_COHERENT);
        if (err) {
                aprint_error(": failed to map ds memory, err=%d\n", err);
                return;
        }
        err = bus_dmamap_create(sc->sc_dmat,
            sizeof(struct osiop_ds) * OSIOP_NACB, 1,
            sizeof(struct osiop_ds) * OSIOP_NACB, 0,
            BUS_DMA_NOWAIT, &sc->sc_dsdma);
        if (err) {
                aprint_error(": failed to create ds map, err=%d\n", err);
                return;
        }
        err = bus_dmamap_load(sc->sc_dmat, sc->sc_dsdma, sc->sc_ds,
            sizeof(struct osiop_ds) * OSIOP_NACB, NULL, BUS_DMA_NOWAIT);
        if (err) {
                aprint_error(": failed to load ds map, err=%d\n", err);
                return;
        }

        acb = malloc(sizeof(struct osiop_acb) * OSIOP_NACB,
            M_DEVBUF, M_WAITOK|M_ZERO);
        sc->sc_acb = acb;
        sc->sc_cfflags = device_cfdata(sc->sc_dev)->cf_flags;
        sc->sc_nexus = NULL;
        sc->sc_active = 0;
        memset(sc->sc_tinfo, 0, sizeof(sc->sc_tinfo));

        /* Initialize command block queue */
        TAILQ_INIT(&sc->ready_list);
        TAILQ_INIT(&sc->nexus_list);
        TAILQ_INIT(&sc->free_list);

        /* Initialize each command block */
        for (i = 0; i < OSIOP_NACB; i++) {
                bus_addr_t dsa;

                err = bus_dmamap_create(sc->sc_dmat, OSIOP_MAX_XFER, OSIOP_NSG,
                    OSIOP_MAX_XFER, 0, BUS_DMA_NOWAIT, &acb->datadma);
                if (err) {
                        aprint_error(": failed to create datadma map, err=%d\n",
                            err);
                        return;
                }

                acb->sc = sc;
                acb->ds = &sc->sc_ds[i];
                acb->dsoffset = sizeof(struct osiop_ds) * i;

                dsa = sc->sc_dsdma->dm_segs[0].ds_addr + acb->dsoffset;
                acb->ds->id.addr = dsa + OSIOP_DSIDOFF;
                acb->ds->cmd.addr = dsa + OSIOP_DSCMDOFF;
                acb->ds->status.count = 1;
                acb->ds->status.addr = dsa + OSIOP_DSSTATOFF;
                acb->ds->msg.count = 1;
                acb->ds->msg.addr = dsa + OSIOP_DSMSGOFF;
                acb->ds->msgin.count = 1;
                acb->ds->msgin.addr = dsa + OSIOP_DSMSGINOFF;
                acb->ds->extmsg.count = 1;
                acb->ds->extmsg.addr = dsa + OSIOP_DSEXTMSGOFF;
                acb->ds->synmsg.count = 3;
                acb->ds->synmsg.addr = dsa + OSIOP_DSSYNMSGOFF;
                TAILQ_INSERT_TAIL(&sc->free_list, acb, chain);

                acb++;
        }

        aprint_normal(": NCR53C710 rev %d, %dMHz, SCSI ID %d\n",
            osiop_read_1(sc, OSIOP_CTEST8) >> 4, sc->sc_clock_freq, sc->sc_id);

        /*
         * Initialize all
         */
        osiop_init(sc);

        /*
         * Fill in the adapter.
         */
        sc->sc_adapter.adapt_dev = sc->sc_dev;
        sc->sc_adapter.adapt_nchannels = 1;
        sc->sc_adapter.adapt_openings = OSIOP_NACB;
        sc->sc_adapter.adapt_max_periph = 1;
        sc->sc_adapter.adapt_ioctl = NULL;
        sc->sc_adapter.adapt_minphys = osiop_minphys;
        sc->sc_adapter.adapt_request = osiop_scsipi_request;

        /*
         * Fill in the channel.
         */
        sc->sc_channel.chan_adapter = &sc->sc_adapter;
        sc->sc_channel.chan_bustype = &scsi_bustype;
        sc->sc_channel.chan_channel = 0;
        sc->sc_channel.chan_ntargets = OSIOP_NTGT;
        sc->sc_channel.chan_nluns = 8;
        sc->sc_channel.chan_id = sc->sc_id;

        /*
         * Now try to attach all the sub devices.
         */
        config_found(sc->sc_dev, &sc->sc_channel, scsiprint, CFARGS_NONE);
}

/*
 * default minphys routine for osiop based controllers
 */
void
osiop_minphys(struct buf *bp)
{

        if (bp->b_bcount > OSIOP_MAX_XFER)
                bp->b_bcount = OSIOP_MAX_XFER;
        minphys(bp);
}

/*
 * used by specific osiop controller
 *
 */
void
osiop_scsipi_request(struct scsipi_channel *chan, scsipi_adapter_req_t req,
    void *arg)
{
        struct scsipi_xfer *xs;
        struct osiop_acb *acb;
        struct osiop_softc *sc;
        int err, flags, s;

        sc = device_private(chan->chan_adapter->adapt_dev);

        switch (req) {
        case ADAPTER_REQ_RUN_XFER:
                xs = arg;
                flags = xs->xs_control;

                /* XXXX ?? */
                if (flags & XS_CTL_DATA_UIO)
                        panic("osiop: scsi data uio requested");

                /* XXXX ?? */
                if (sc->sc_nexus && flags & XS_CTL_POLL)
#if 0
                        panic("osiop_scsicmd: busy");
#else
                        printf("osiop_scsicmd: busy\n");
#endif

                s = splbio();
                acb = TAILQ_FIRST(&sc->free_list);
                if (acb != NULL) {
                        TAILQ_REMOVE(&sc->free_list, acb, chain);
                }
#ifdef DIAGNOSTIC
                else {
                        scsipi_printaddr(xs->xs_periph);
                        printf("unable to allocate acb\n");
                        panic("osiop_scsipi_request");
                }
#endif

                acb->status = ACB_S_READY;
                acb->xs = xs;

                /* Setup DMA map for data buffer */
                if (xs->xs_control & (XS_CTL_DATA_IN | XS_CTL_DATA_OUT)) {
                        err = bus_dmamap_load(sc->sc_dmat, acb->datadma,
                            xs->data, xs->datalen, NULL,
                            BUS_DMA_NOWAIT | BUS_DMA_STREAMING |
                            ((xs->xs_control & XS_CTL_DATA_IN) ?
                             BUS_DMA_READ : BUS_DMA_WRITE));
                        if (err) {
                                printf("%s: unable to load data DMA map: %d\n",
                                    device_xname(sc->sc_dev), err);
                                xs->error = XS_DRIVER_STUFFUP;
                                scsipi_done(xs);
                                TAILQ_INSERT_TAIL(&sc->free_list, acb, chain);
                                splx(s);
                                return;
                        }
                }

                acb->cmdlen = xs->cmdlen;
                acb->datalen = xs->datalen;
#ifdef OSIOP_DEBUG
                acb->data = xs->data;
#endif

                TAILQ_INSERT_TAIL(&sc->ready_list, acb, chain);

                if (sc->sc_nexus == NULL)
                        osiop_sched(sc);

                splx(s);

                if (flags & XS_CTL_POLL || sc->sc_flags & OSIOP_NODMA)
                        osiop_poll(sc, acb);
                return;

        case ADAPTER_REQ_GROW_RESOURCES:
                return;

        case ADAPTER_REQ_SET_XFER_MODE:
                {
                        struct osiop_tinfo *ti;
                        struct scsipi_xfer_mode *xm = arg;

                        ti = &sc->sc_tinfo[xm->xm_target];

                        if ((xm->xm_mode & PERIPH_CAP_SYNC) != 0 &&
                            (ti->flags & TI_NOSYNC) == 0)
                                ti->state = NEG_INIT;

                        /*
                         * If we're not going to negotiate, send the
                         * notification now, since it won't happen later.
                         */
                        if (ti->state == NEG_DONE)
                                osiop_update_xfer_mode(sc, xm->xm_target);

                        return;
                }
        }
}

void
osiop_poll(struct osiop_softc *sc, struct osiop_acb *acb)
{
        struct scsipi_xfer *xs = acb->xs;
        int status, i, s, to;
        uint8_t istat, dstat, sstat0;

        s = splbio();
        to = xs->timeout / 1000;
        if (!TAILQ_EMPTY(&sc->nexus_list))
                printf("%s: osiop_poll called with disconnected device\n",
                    device_xname(sc->sc_dev));
        for (;;) {
                i = 1000;
                while (((istat = osiop_read_1(sc, OSIOP_ISTAT)) &
                    (OSIOP_ISTAT_SIP | OSIOP_ISTAT_DIP)) == 0) {
                        if (i <= 0) {
#ifdef OSIOP_DEBUG
                                printf("waiting: tgt %d cmd %02x sbcl %02x"
                                    " dsp %x (+%lx) dcmd %x"
                                    " ds %p timeout %d\n",
                                    xs->xs_periph->periph_target,
                                    xs->cmd->opcode,
                                    osiop_read_1(sc, OSIOP_SBCL),
                                    osiop_read_4(sc, OSIOP_DSP),
                                    osiop_read_4(sc, OSIOP_DSP) -
                                        sc->sc_scrdma->dm_segs[0].ds_addr,
                                    osiop_read_1(sc, OSIOP_DCMD),
                                    acb->ds, acb->xs->timeout);
#endif
                                i = 1000;
                                to--;
                                if (to <= 0) {
                                        osiop_reset(sc);
                                        splx(s);
                                        return;
                                }
                        }
                        delay(1000);
                        i--;
                }
                sstat0 = osiop_read_1(sc, OSIOP_SSTAT0);
                delay(25);
                dstat = osiop_read_1(sc, OSIOP_DSTAT);
                if (osiop_checkintr(sc, istat, dstat, sstat0, &status)) {
                        if (acb != sc->sc_nexus)
                                printf("%s: osiop_poll disconnected device"
                                    " completed\n", device_xname(sc->sc_dev));
                        else if ((sc->sc_flags & OSIOP_INTDEFER) == 0) {
                                sc->sc_flags &= ~OSIOP_INTSOFF;
                                osiop_write_1(sc, OSIOP_SIEN, sc->sc_sien);
                                osiop_write_1(sc, OSIOP_DIEN, sc->sc_dien);
                        }
                        osiop_scsidone(sc->sc_nexus, status);
                }

                if (xs->xs_status & XS_STS_DONE)
                        break;
        }

        splx(s);
        return;
}

/*
 * start next command that's ready
 */
void
osiop_sched(struct osiop_softc *sc)
{
        struct scsipi_periph *periph;
        struct osiop_acb *acb;
        int i;

#ifdef OSIOP_DEBUG
        if (sc->sc_nexus != NULL) {
                printf("%s: osiop_sched- nexus %p/%d ready %p/%d\n",
                    device_xname(sc->sc_dev), sc->sc_nexus,
                    sc->sc_nexus->xs->xs_periph->periph_target,
                    TAILQ_FIRST(&sc->ready_list),
                    TAILQ_FIRST(&sc->ready_list)->xs->xs_periph->periph_target);
                return;
        }
#endif
        TAILQ_FOREACH(acb, &sc->ready_list, chain) {
                periph = acb->xs->xs_periph;
                i = periph->periph_target;
                if ((sc->sc_tinfo[i].lubusy & (1 << periph->periph_lun)) == 0) {
                        struct osiop_tinfo *ti;

                        TAILQ_REMOVE(&sc->ready_list, acb, chain);
                        sc->sc_nexus = acb;
                        ti = &sc->sc_tinfo[i];
                        ti->lubusy |= (1 << periph->periph_lun);
                        break;
                }
        }

        if (acb == NULL) {
#ifdef OSIOP_DEBUG
                printf("%s: osiop_sched didn't find ready command\n",
                    device_xname(sc->sc_dev));
#endif
                return;
        }

        if (acb->xs->xs_control & XS_CTL_RESET)
                osiop_reset(sc);

        sc->sc_active++;
        osiop_select(sc);
}

void
osiop_scsidone(struct osiop_acb *acb, int status)
{
        struct scsipi_xfer *xs;
        struct scsipi_periph *periph;
        struct osiop_softc *sc;
        int dosched = 0;

#ifdef DIAGNOSTIC
        if (acb == NULL || acb->xs == NULL) {
                printf("osiop_scsidone: NULL acb or scsipi_xfer\n");
#if defined(OSIOP_DEBUG) && defined(DDB)
                Debugger();
#endif
                return;
        }
#endif
        xs = acb->xs;
        sc = acb->sc;
        periph = xs->xs_periph;

#ifdef OSIOP_DEBUG
        if (acb->status != ACB_S_DONE)
                printf("%s: acb not done (status %d)\n",
                    device_xname(sc->sc_dev), acb->status);
#endif

        xs->status = status;

        switch (status) {
        case SCSI_OK:
                xs->error = XS_NOERROR;
                break;
        case SCSI_BUSY:
                xs->error = XS_BUSY;
                break;
        case SCSI_CHECK:
                xs->error = XS_BUSY;
                break;
        case SCSI_OSIOP_NOCHECK:
                /*
                 * don't check status, xs->error is already valid
                 */
                break;
        case SCSI_OSIOP_NOSTATUS:
                /*
                 * the status byte was not updated, cmd was
                 * aborted
                 */
                xs->error = XS_SELTIMEOUT;
                break;
        default:
#ifdef OSIOP_DEBUG
                printf("%s: osiop_scsidone: unknown status code (0x%02x)\n",
                    device_xname(sc->sc_dev), status);
#endif
                xs->error = XS_DRIVER_STUFFUP;
                break;
        }

        if (xs->xs_control & (XS_CTL_DATA_IN | XS_CTL_DATA_OUT)) {
                bus_dmamap_sync(sc->sc_dmat, acb->datadma, 0, acb->datalen,
                    (xs->xs_control & XS_CTL_DATA_IN) ?
                    BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);
                bus_dmamap_unload(sc->sc_dmat, acb->datadma);
        }

        /*
         * Remove the ACB from whatever queue it's on.  We have to do a bit of
         * a hack to figure out which queue it's on.  Note that it is *not*
         * necessary to cdr down the ready queue, but we must cdr down the
         * nexus queue and see if it's there, so we can mark the unit as no
         * longer busy.  This code is sickening, but it works.
         */
        if (acb == sc->sc_nexus) {
                sc->sc_nexus = NULL;
                sc->sc_tinfo[periph->periph_target].lubusy &=
                    ~(1 << periph->periph_lun);
                if (!TAILQ_EMPTY(&sc->ready_list))
                        dosched = 1;    /* start next command */
                sc->sc_active--;
                OSIOP_TRACE('d', 'a', status, 0);
        } else if (sc->ready_list.tqh_last == &TAILQ_NEXT(acb, chain)) {
                TAILQ_REMOVE(&sc->ready_list, acb, chain);
                OSIOP_TRACE('d', 'r', status, 0);
        } else {
                struct osiop_acb *acb2;
                TAILQ_FOREACH(acb2, &sc->nexus_list, chain) {
                        if (acb2 == acb) {
                                TAILQ_REMOVE(&sc->nexus_list, acb, chain);
                                sc->sc_tinfo[periph->periph_target].lubusy &=
                                    ~(1 << periph->periph_lun);
                                sc->sc_active--;
                                break;
                        }
                }
                if (acb2 == NULL) {
                        if (TAILQ_NEXT(acb, chain) != NULL) {
                                TAILQ_REMOVE(&sc->ready_list, acb, chain);
                                sc->sc_active--;
                        } else {
                                printf("%s: can't find matching acb\n",
                                    device_xname(sc->sc_dev));
#ifdef DDB
#if 0
                                Debugger();
#endif
#endif
                        }
                }
                OSIOP_TRACE('d', 'n', status, 0);
        }
        /* Put it on the free list. */
        acb->status = ACB_S_FREE;
        TAILQ_INSERT_TAIL(&sc->free_list, acb, chain);
        sc->sc_tinfo[periph->periph_target].cmds++;

        callout_stop(&xs->xs_callout);
        xs->resid = 0;
        scsipi_done(xs);

        if (dosched && sc->sc_nexus == NULL)
                osiop_sched(sc);
}

void
osiop_abort(struct osiop_softc *sc, const char *where)
{

        printf("%s: abort %s: dstat %02x, sstat0 %02x sbcl %02x\n",
            device_xname(sc->sc_dev), where,
            osiop_read_1(sc, OSIOP_DSTAT),
            osiop_read_1(sc, OSIOP_SSTAT0),
            osiop_read_1(sc, OSIOP_SBCL));

        /* XXX XXX XXX */
        if (sc->sc_active > 0) {
                sc->sc_active = 0;
        }
}

void
osiop_init(struct osiop_softc *sc)
{
        int i, inhibit_sync, inhibit_disc;

        sc->sc_tcp[1] = 1000 / sc->sc_clock_freq;
        sc->sc_tcp[2] = 1500 / sc->sc_clock_freq;
        sc->sc_tcp[3] = 2000 / sc->sc_clock_freq;
        sc->sc_minsync = sc->sc_tcp[1];         /* in 4ns units */

        if (sc->sc_minsync < 25)
                sc->sc_minsync = 25;

        if (sc->sc_clock_freq <= 25) {
                sc->sc_dcntl |= OSIOP_DCNTL_CF_1;       /* SCLK/1 */
                sc->sc_tcp[0] = sc->sc_tcp[1];
        } else if (sc->sc_clock_freq <= 37) {
                sc->sc_dcntl |= OSIOP_DCNTL_CF_1_5;     /* SCLK/1.5 */
                sc->sc_tcp[0] = sc->sc_tcp[2];
        } else if (sc->sc_clock_freq <= 50) {
                sc->sc_dcntl |= OSIOP_DCNTL_CF_2;       /* SCLK/2 */
                sc->sc_tcp[0] = sc->sc_tcp[3];
        } else {
                sc->sc_dcntl |= OSIOP_DCNTL_CF_3;       /* SCLK/3 */
                sc->sc_tcp[0] = 3000 / sc->sc_clock_freq;
        }

        if ((sc->sc_cfflags & 0x10000) != 0) {
                sc->sc_flags |= OSIOP_NODMA;
#ifdef OSIOP_DEBUG
                printf("%s: DMA disabled; use polling\n",
                    device_xname(sc->sc_dev));
#endif
        }

        inhibit_sync = (sc->sc_cfflags & 0xff00) >> 8;  /* XXX */
        inhibit_disc =  sc->sc_cfflags & 0x00ff;        /* XXX */
#ifdef OSIOP_DEBUG
        if (inhibit_sync != 0)
                printf("%s: Inhibiting synchronous transfer: 0x%02x\n",
                    device_xname(sc->sc_dev), inhibit_sync);
        if (inhibit_disc != 0)
                printf("%s: Inhibiting disconnect: 0x%02x\n",
                    device_xname(sc->sc_dev), inhibit_disc);
#endif
        for (i = 0; i < OSIOP_NTGT; i++) {
                if (inhibit_sync & (1 << i))
                        sc->sc_tinfo[i].flags |= TI_NOSYNC;
                if (inhibit_disc & (1 << i))
                        sc->sc_tinfo[i].flags |= TI_NODISC;
        }

        osiop_resetbus(sc);
        osiop_reset(sc);
}

void
osiop_reset(struct osiop_softc *sc)
{
        struct osiop_acb *acb;
        int i, s;
        uint8_t stat;

#ifdef OSIOP_DEBUG
        printf("%s: resetting chip\n", device_xname(sc->sc_dev));
#endif
        if (sc->sc_flags & OSIOP_ALIVE)
                osiop_abort(sc, "reset");

        s = splbio();

        /*
         * Reset the chip
         * XXX - is this really needed?
         */

        /* abort current script */
        osiop_write_1(sc, OSIOP_ISTAT,
            osiop_read_1(sc, OSIOP_ISTAT) | OSIOP_ISTAT_ABRT);
        /* reset chip */
        osiop_write_1(sc, OSIOP_ISTAT,
            osiop_read_1(sc, OSIOP_ISTAT) | OSIOP_ISTAT_RST);
        delay(100);
        osiop_write_1(sc, OSIOP_ISTAT,
            osiop_read_1(sc, OSIOP_ISTAT) & ~OSIOP_ISTAT_RST);
        delay(100);

        /*
         * Set up various chip parameters
         */
        osiop_write_1(sc, OSIOP_SCNTL0,
            OSIOP_ARB_FULL | OSIOP_SCNTL0_EPC | OSIOP_SCNTL0_EPG);
        osiop_write_1(sc, OSIOP_SCNTL1, OSIOP_SCNTL1_ESR);
        osiop_write_1(sc, OSIOP_DCNTL, sc->sc_dcntl);
        osiop_write_1(sc, OSIOP_DMODE, OSIOP_DMODE_BL4);
        /* don't enable interrupts yet */
        osiop_write_1(sc, OSIOP_SIEN, 0x00);
        osiop_write_1(sc, OSIOP_DIEN, 0x00);
        osiop_write_1(sc, OSIOP_SCID, OSIOP_SCID_VALUE(sc->sc_id));
        osiop_write_1(sc, OSIOP_DWT, 0x00);
        osiop_write_1(sc, OSIOP_CTEST0, osiop_read_1(sc, OSIOP_CTEST0)
            | OSIOP_CTEST0_BTD | OSIOP_CTEST0_EAN);
        osiop_write_1(sc, OSIOP_CTEST7,
            osiop_read_1(sc, OSIOP_CTEST7) | sc->sc_ctest7);
        osiop_write_1(sc, OSIOP_CTEST4,
            osiop_read_1(sc, OSIOP_CTEST4) | sc->sc_ctest4);

        /* will need to re-negotiate sync xfers */
        for (i = 0; i < OSIOP_NTGT; i++) {
                sc->sc_tinfo[i].state = NEG_INIT;
                sc->sc_tinfo[i].period = 0;
                sc->sc_tinfo[i].offset = 0;
        }

        stat = osiop_read_1(sc, OSIOP_ISTAT);
        if (stat & OSIOP_ISTAT_SIP)
                osiop_read_1(sc, OSIOP_SSTAT0);
        delay(25);
        if (stat & OSIOP_ISTAT_DIP)
                osiop_read_1(sc, OSIOP_DSTAT);

        splx(s);

        delay(osiop_reset_delay * 1000);

        if (sc->sc_nexus != NULL) {
                sc->sc_nexus->xs->error =
                    (sc->sc_nexus->flags & ACB_F_TIMEOUT) ?
                    XS_TIMEOUT : XS_RESET;
                sc->sc_nexus->status = ACB_S_DONE;
                sc->sc_nexus->flags = 0;
                osiop_scsidone(sc->sc_nexus, SCSI_OSIOP_NOCHECK);
        }
        while ((acb = TAILQ_FIRST(&sc->nexus_list)) != NULL) {
                acb->xs->error = (acb->flags & ACB_F_TIMEOUT) ?
                    XS_TIMEOUT : XS_RESET;
                acb->status = ACB_S_DONE;
                acb->flags = 0;
                osiop_scsidone(acb, SCSI_OSIOP_NOCHECK);
        }

        sc->sc_flags &= ~(OSIOP_INTDEFER | OSIOP_INTSOFF);
        /* enable SCSI and DMA interrupts */
        sc->sc_sien = OSIOP_SIEN_M_A | OSIOP_SIEN_STO | /*OSIOP_SIEN_SEL |*/
            OSIOP_SIEN_SGE | OSIOP_SIEN_UDC | OSIOP_SIEN_RST | OSIOP_SIEN_PAR;
        sc->sc_dien = OSIOP_DIEN_BF | OSIOP_DIEN_ABRT | OSIOP_DIEN_SIR |
            /*OSIOP_DIEN_WTD |*/ OSIOP_DIEN_IID;
        osiop_write_1(sc, OSIOP_SIEN, sc->sc_sien);
        osiop_write_1(sc, OSIOP_DIEN, sc->sc_dien);
}

void
osiop_resetbus(struct osiop_softc *sc)
{

        osiop_write_1(sc, OSIOP_SIEN, 0);
        osiop_write_1(sc, OSIOP_SCNTL1,
            osiop_read_1(sc, OSIOP_SCNTL1) | OSIOP_SCNTL1_RST);
        delay(25);
        osiop_write_1(sc, OSIOP_SCNTL1,
            osiop_read_1(sc, OSIOP_SCNTL1) & ~OSIOP_SCNTL1_RST);
}

/*
 * Setup Data Storage for 53C710 and start SCRIPTS processing
 */

void
osiop_start(struct osiop_softc *sc)
{
        struct osiop_acb *acb = sc->sc_nexus;
        struct osiop_ds *ds = acb->ds;
        struct scsipi_xfer *xs = acb->xs;
        bus_dmamap_t dsdma = sc->sc_dsdma, datadma = acb->datadma;
        struct osiop_tinfo *ti;
        int target = xs->xs_periph->periph_target;
        int lun = xs->xs_periph->periph_lun;
        int disconnect, i;

#ifdef OSIOP_DEBUG
        if (osiop_debug & DEBUG_DISC &&
            osiop_read_1(sc, OSIOP_SBCL) & OSIOP_BSY) {
                printf("ACK! osiop was busy: script %p dsa %p active %d\n",
                    sc->sc_script, acb->ds, sc->sc_active);
                printf("istat %02x sfbr %02x lcrc %02x sien %02x dien %02x\n",
                    osiop_read_1(sc, OSIOP_ISTAT),
                    osiop_read_1(sc, OSIOP_SFBR),
                    osiop_read_1(sc, OSIOP_LCRC),
                    osiop_read_1(sc, OSIOP_SIEN),
                    osiop_read_1(sc, OSIOP_DIEN));
#ifdef DDB
#if 0
                Debugger();
#endif
#endif
        }
#endif

#ifdef OSIOP_DEBUG
        if (acb->status != ACB_S_READY)
                panic("osiop_start: non-ready cmd in acb");
#endif

        acb->intstat = 0;

        /* Copy SCSI command to DMA buffer */
        memcpy(ds->scsipi_cmd, xs->cmd, acb->cmdlen);
        ds->cmd.count = acb->cmdlen;

        ti = &sc->sc_tinfo[target];
        ds->scsi_addr = ((1 << 16) << target) | (ti->sxfer << 8);

        disconnect = (xs->xs_control & XS_CTL_REQSENSE) == 0 &&
            (ti->flags & TI_NODISC) == 0;

        ds->msgout[0] = MSG_IDENTIFY(lun, disconnect);
        ds->id.count = 1;
        ds->stat[0] = SCSI_OSIOP_NOSTATUS;      /* set invalid status */
        ds->msgbuf[0] = ds->msgbuf[1] = MSG_INVALID;
        memset(&ds->data, 0, sizeof(ds->data));

        /*
         * Negotiate wide is the initial negotiation state;  since the 53c710
         * doesn't do wide transfers, just begin the synchronous transfer
         * negotiation here.
         */
        if (ti->state == NEG_INIT) {
                if ((ti->flags & TI_NOSYNC) != 0) {
                        ti->state = NEG_DONE;
                        ti->sbcl = 0;
                        ti->sxfer = 0;
                        ti->period = 0;
                        ti->offset = 0;
                        osiop_update_xfer_mode(sc, target);
#ifdef OSIOP_DEBUG
                        if (osiopsync_debug)
                                printf("Forcing target %d asynchronous\n",
                                    target);
#endif
                } else {
                        ds->msgbuf[2] = MSG_INVALID;
                        ds->msgout[1] = MSG_EXTENDED;
                        ds->msgout[2] = MSG_EXT_SDTR_LEN;
                        ds->msgout[3] = MSG_EXT_SDTR;
                        ds->msgout[4] = sc->sc_minsync;
                        ds->msgout[5] = OSIOP_MAX_OFFSET;
                        ds->id.count = MSG_EXT_SDTR_LEN + 3;
                        ti->state = NEG_WAITS;
#ifdef OSIOP_DEBUG
                        if (osiopsync_debug)
                                printf("Sending sync request to target %d\n",
                                    target);
#endif
                }
        }

        acb->curaddr = 0;
        acb->curlen = 0;

        /*
         * Build physical DMA addresses for scatter/gather I/O
         */
        if (xs->xs_control & (XS_CTL_DATA_IN | XS_CTL_DATA_OUT)) {
                for (i = 0; i < datadma->dm_nsegs; i++) {
                        ds->data[i].count = datadma->dm_segs[i].ds_len;
                        ds->data[i].addr  = datadma->dm_segs[i].ds_addr;
                }
                /* sync xfer data buffer */
                bus_dmamap_sync(sc->sc_dmat, acb->datadma,
                    0, acb->datalen, (xs->xs_control & XS_CTL_DATA_IN) ?
                    BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);
        }

        /* sync script data structure */
        bus_dmamap_sync(sc->sc_dmat, dsdma,
            acb->dsoffset, sizeof(struct osiop_ds),
            BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);

        acb->status = ACB_S_ACTIVE;

        /* handle timeout */
        if ((xs->xs_control & XS_CTL_POLL) == 0) {
                int timeout = mstohz(acb->xs->timeout);
                /* start expire timer */
                if (timeout == 0)
                        timeout = 1;
                callout_reset(&xs->xs_callout, timeout,
                    osiop_timeout, acb);
        }
#ifdef OSIOP_DEBUG
        if (osiop_debug & DEBUG_DISC &&
            osiop_read_1(sc, OSIOP_SBCL) & OSIOP_BSY) {
                printf("ACK! osiop was busy at start: "
                    "script %p dsa %p active %d\n",
                    sc->sc_script, acb->ds, sc->sc_active);
#ifdef DDB
#if 0
                Debugger();
#endif
#endif
        }
#endif
        if (TAILQ_EMPTY(&sc->nexus_list)) {
                if (osiop_read_1(sc, OSIOP_ISTAT) & OSIOP_ISTAT_CON)
                        printf("%s: osiop_select while connected?\n",
                            device_xname(sc->sc_dev));
                osiop_write_4(sc, OSIOP_TEMP, 0);
                osiop_write_1(sc, OSIOP_SBCL, ti->sbcl);
                osiop_write_4(sc, OSIOP_DSA,
                    dsdma->dm_segs[0].ds_addr + acb->dsoffset);
                osiop_write_4(sc, OSIOP_DSP,
                    sc->sc_scrdma->dm_segs[0].ds_addr + Ent_scripts);
                OSIOP_TRACE('s', 1, 0, 0);
        } else {
                if ((osiop_read_1(sc, OSIOP_ISTAT) & OSIOP_ISTAT_CON) == 0) {
                        osiop_write_1(sc, OSIOP_ISTAT, OSIOP_ISTAT_SIGP);
                        OSIOP_TRACE('s', 2, 0, 0);
                } else {
                        OSIOP_TRACE('s', 3,
                            osiop_read_1(sc, OSIOP_ISTAT), 0);
                }
        }
#ifdef OSIOP_DEBUG
        osiopstarts++;
#endif
}

/*
 * Process a DMA or SCSI interrupt from the 53C710 SIOP
 */

int
osiop_checkintr(struct osiop_softc *sc, uint8_t istat, uint8_t dstat,
    uint8_t sstat0, int *status)
{
        struct osiop_acb *acb = sc->sc_nexus;
        struct osiop_ds *ds = NULL;     /* XXX */
        bus_dmamap_t dsdma = sc->sc_dsdma;
        bus_addr_t scraddr = sc->sc_scrdma->dm_segs[0].ds_addr;
        int target = 0;
        int dfifo, dbc, intcode, sstat1;

        dfifo = osiop_read_1(sc, OSIOP_DFIFO);
        dbc = osiop_read_4(sc, OSIOP_DBC) & 0x00ffffff;
        sstat1 = osiop_read_1(sc, OSIOP_SSTAT1);
        osiop_write_1(sc, OSIOP_CTEST8,
            osiop_read_1(sc, OSIOP_CTEST8) | OSIOP_CTEST8_CLF);
        while ((osiop_read_1(sc, OSIOP_CTEST1) & OSIOP_CTEST1_FMT) !=
            OSIOP_CTEST1_FMT)
                ;
        osiop_write_1(sc, OSIOP_CTEST8,
            osiop_read_1(sc, OSIOP_CTEST8) & ~OSIOP_CTEST8_CLF);
        intcode = osiop_read_4(sc, OSIOP_DSPS);
#ifdef OSIOP_DEBUG
        osiopints++;
        if (osiop_read_4(sc, OSIOP_DSP) != 0 &&
            (osiop_read_4(sc, OSIOP_DSP) < scraddr ||
            osiop_read_4(sc, OSIOP_DSP) >= scraddr + sizeof(osiop_script))) {
                printf("%s: dsp not within script dsp %x scripts %lx:%lx",
                    device_xname(sc->sc_dev),
                    osiop_read_4(sc, OSIOP_DSP),
                    scraddr, scraddr + sizeof(osiop_script));
                printf(" istat %x dstat %x sstat0 %x\n", istat, dstat, sstat0);
#ifdef DDB
                Debugger();
#endif
        }
#endif
        OSIOP_TRACE('i', dstat, istat, (istat & OSIOP_ISTAT_DIP) ?
            intcode & 0xff : sstat0);

        if (acb != NULL) { /* XXX */
                ds = acb->ds;
                bus_dmamap_sync(sc->sc_dmat, dsdma,
                    acb->dsoffset, sizeof(struct osiop_ds),
                    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
#ifdef OSIOP_DEBUG
                if (acb->status != ACB_S_ACTIVE)
                        printf("osiop_checkintr: acb not active (status %d)\n",
                            acb->status);
#endif
        }


        if (dstat & OSIOP_DSTAT_SIR && intcode == A_ok) {
                /* Normal completion status, or check condition */
                struct osiop_tinfo *ti;

                if (acb == NULL) {
                        printf("%s: COMPLETE with no active command?\n",
                            device_xname(sc->sc_dev));
                        goto bad_phase;
                }
#ifdef OSIOP_DEBUG
                if (osiop_read_4(sc, OSIOP_DSA) !=
                    dsdma->dm_segs[0].ds_addr + acb->dsoffset) {
                        printf("osiop: invalid dsa: %x %lx\n",
                            osiop_read_4(sc, OSIOP_DSA),
                            dsdma->dm_segs[0].ds_addr + acb->dsoffset);
                        panic("*** osiop DSA invalid ***");
                }
#endif
                target = acb->xs->xs_periph->periph_target;
                ti = &sc->sc_tinfo[target];
                if (ti->state == NEG_WAITS) {
                        if (ds->msgbuf[1] == MSG_INVALID)
                                printf("%s: target %d ignored sync request\n",
                                    device_xname(sc->sc_dev), target);
                        else if (ds->msgbuf[1] == MSG_MESSAGE_REJECT)
                                printf("%s: target %d rejected sync request\n",
                                    device_xname(sc->sc_dev), target);
                        ti->period = 0;
                        ti->offset = 0;
                        osiop_update_xfer_mode(sc, target);
                        ti->state = NEG_DONE;
                }
#ifdef OSIOP_DEBUG
                if (osiop_read_1(sc, OSIOP_SBCL) & OSIOP_BSY) {
#if 0
                        printf("ACK! osiop was busy at end: "
                            "script %p dsa %p\n", &osiop_script, ds);
#ifdef DDB
                        Debugger();
#endif
#endif
                }
                if (ds->msgbuf[0] != MSG_CMDCOMPLETE)
                        printf("%s: message was not COMMAND COMPLETE: %02x\n",
                            device_xname(sc->sc_dev), ds->msgbuf[0]);
#endif
                if (!TAILQ_EMPTY(&sc->nexus_list))
                        osiop_write_1(sc, OSIOP_DCNTL,
                            osiop_read_1(sc, OSIOP_DCNTL) | OSIOP_DCNTL_STD);
                *status = ds->stat[0];
                acb->status = ACB_S_DONE;
                return (1);
        }
        if (dstat & OSIOP_DSTAT_SIR && intcode == A_int_syncmsg) {
                if (acb == NULL) {
                        printf("%s: sync message with no active command?\n",
                            device_xname(sc->sc_dev));
                        goto bad_phase;
                }
                target = acb->xs->xs_periph->periph_target;
                if (ds->msgbuf[1] == MSG_EXTENDED &&
                    ds->msgbuf[2] == MSG_EXT_SDTR_LEN &&
                    ds->msgbuf[3] == MSG_EXT_SDTR) {
                        struct osiop_tinfo *ti = &sc->sc_tinfo[target];
#ifdef OSIOP_DEBUG
                        if (osiopsync_debug)
                                printf("sync msg in: "
                                    "%02x %02x %02x %02x %02x %02x\n",
                                    ds->msgbuf[0], ds->msgbuf[1],
                                    ds->msgbuf[2], ds->msgbuf[3],
                                    ds->msgbuf[4], ds->msgbuf[5]);
#endif
                        ti->period = ds->msgbuf[4];
                        ti->offset = ds->msgbuf[5];
                        ti->sxfer = 0;
                        ti->sbcl = 0;
                        if (ds->msgbuf[5] != 0)
                                scsi_period_to_osiop(sc, target);
                        osiop_update_xfer_mode(sc, target);

                        bus_dmamap_sync(sc->sc_dmat, dsdma,
                            acb->dsoffset, sizeof(struct osiop_ds),
                            BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
                        osiop_write_1(sc, OSIOP_SXFER, ti->sxfer);
                        osiop_write_1(sc, OSIOP_SBCL, ti->sbcl);
                        if (ti->state == NEG_WAITS) {
                                ti->state = NEG_DONE;
                                osiop_write_4(sc, OSIOP_DSP,
                                    scraddr + Ent_clear_ack);
                                return (0);
                        }
                        osiop_write_1(sc, OSIOP_DCNTL,
                            osiop_read_1(sc, OSIOP_DCNTL) | OSIOP_DCNTL_STD);
                        ti->state = NEG_DONE;
                        return (0);
                }
                /* XXX - not SDTR message */
        }
        if (sstat0 & OSIOP_SSTAT0_M_A) {
                /* Phase mismatch */
#ifdef OSIOP_DEBUG
                osiopphmm++;
#endif
                if (acb == NULL) {
                        printf("%s: Phase mismatch with no active command?\n",
                            device_xname(sc->sc_dev));
                        goto bad_phase;
                }
                if (acb->datalen > 0) {
                        int adjust = (dfifo - (dbc & 0x7f)) & 0x7f;
                        if (sstat1 & OSIOP_SSTAT1_ORF)
                                adjust++;
                        if (sstat1 & OSIOP_SSTAT1_OLF)
                                adjust++;
                        acb->curaddr = osiop_read_4(sc, OSIOP_DNAD) - adjust;
                        acb->curlen = dbc + adjust;
#ifdef OSIOP_DEBUG
                        if (osiop_debug & DEBUG_DISC) {
                                printf("Phase mismatch: curaddr %lx "
                                    "curlen %lx dfifo %x dbc %x sstat1 %x "
                                    "adjust %x sbcl %x starts %d acb %p\n",
                                    acb->curaddr, acb->curlen, dfifo,
                                    dbc, sstat1, adjust,
                                    osiop_read_1(sc, OSIOP_SBCL),
                                    osiopstarts, acb);
                                if (ds->data[1].count != 0) {
                                        int i;
                                        for (i = 0; ds->data[i].count != 0; i++)
                                                printf("chain[%d] "
                                                    "addr %x len %x\n", i,
                                                    ds->data[i].addr,
                                                    ds->data[i].count);
                                }
                                bus_dmamap_sync(sc->sc_dmat, dsdma,
                                    acb->dsoffset, sizeof(struct osiop_ds),
                                    BUS_DMASYNC_PREREAD |
                                    BUS_DMASYNC_PREWRITE);
                        }
#endif
                }
#ifdef OSIOP_DEBUG
                OSIOP_TRACE('m', osiop_read_1(sc, OSIOP_SBCL),
                    osiop_read_4(sc, OSIOP_DSP) >> 8,
                    osiop_read_4(sc, OSIOP_DSP));
                if (osiop_debug & DEBUG_PHASE)
                        printf("Phase mismatch: %x dsp +%lx dcmd %x\n",
                            osiop_read_1(sc, OSIOP_SBCL),
                            osiop_read_4(sc, OSIOP_DSP) - scraddr,
                            osiop_read_4(sc, OSIOP_DBC));
#endif
                if ((osiop_read_1(sc, OSIOP_SBCL) & OSIOP_REQ) == 0) {
                        printf("Phase mismatch: "
                            "REQ not asserted! %02x dsp %x\n",
                            osiop_read_1(sc, OSIOP_SBCL),
                            osiop_read_4(sc, OSIOP_DSP));
#if defined(OSIOP_DEBUG) && defined(DDB)
                        /*Debugger(); XXX is*/
#endif
                }
                switch (OSIOP_PHASE(osiop_read_1(sc, OSIOP_SBCL))) {
                case DATA_OUT_PHASE:
                case DATA_IN_PHASE:
                case STATUS_PHASE:
                case COMMAND_PHASE:
                case MSG_IN_PHASE:
                case MSG_OUT_PHASE:
                        osiop_write_4(sc, OSIOP_DSP, scraddr + Ent_switch);
                        break;
                default:
                        printf("%s: invalid phase\n", device_xname(sc->sc_dev));
                        goto bad_phase;
                }
                return (0);
        }
        if (sstat0 & OSIOP_SSTAT0_STO) {
                /* Select timed out */
                if (acb == NULL) {
                        printf("%s: Select timeout with no active command?\n",
                            device_xname(sc->sc_dev));
                        goto bad_phase;
                }
#ifdef OSIOP_DEBUG
                if (osiop_read_1(sc, OSIOP_SBCL) & OSIOP_BSY) {
                        printf("ACK! osiop was busy at timeout: "
                            "script %p dsa %lx\n", sc->sc_script,
                            dsdma->dm_segs[0].ds_addr + acb->dsoffset);
                        printf(" sbcl %x sdid %x "
                            "istat %x dstat %x sstat0 %x\n",
                            osiop_read_1(sc, OSIOP_SBCL),
                            osiop_read_1(sc, OSIOP_SDID),
                            istat, dstat, sstat0);
                        if ((osiop_read_1(sc, OSIOP_SBCL) & OSIOP_BSY) == 0) {
                                printf("Yikes, it's not busy now!\n");
#if 0
                                *status = SCSI_OSIOP_NOSTATUS;
                                if (!TAILQ_EMPTY(&sc->nexus_list))
                                        osiop_write_4(sc, OSIOP_DSP,
                                            scraddr + Ent_wait_reselect);
                                return (1);
#endif
                        }
#if 0
                        osiop_write_1(sc, OSIOP_DCNTL,
                            osiop_read_1(sc, OSIOP_DCNTL) | OSIOP_DCNTL_STD);
#endif
#ifdef DDB
                        Debugger();
#endif
                        return (0);
                }
#endif
                acb->status = ACB_S_DONE;
                *status = SCSI_OSIOP_NOSTATUS;
                acb->xs->error = XS_SELTIMEOUT;
                if (!TAILQ_EMPTY(&sc->nexus_list))
                        osiop_write_4(sc, OSIOP_DSP,
                            scraddr + Ent_wait_reselect);
                return (1);
        }
        if (acb != NULL)
                target = acb->xs->xs_periph->periph_target;
        else
                target = sc->sc_id;
        if (sstat0 & OSIOP_SSTAT0_UDC) {
                printf("%s: target %d disconnected unexpectedly",
                    device_xname(sc->sc_dev), target);
                if (acb == NULL)
                        printf("with no active command?");
                printf("\n");
#if 0
                osiop_abort(sc, "osiop_chkintr");
#endif
                *status = SCSI_CHECK;
                if (!TAILQ_EMPTY(&sc->nexus_list))
                        osiop_write_4(sc, OSIOP_DSP,
                            scraddr + Ent_wait_reselect);
                return (acb != NULL);
        }
        if (dstat & OSIOP_DSTAT_SIR &&
            (intcode == A_int_disc || intcode == A_int_disc_wodp)) {
                /* Disconnect */
                if (acb == NULL) {
                        printf("%s: Disconnect with no active command?\n",
                            device_xname(sc->sc_dev));
                        return (0);
                }
#ifdef OSIOP_DEBUG
                if (osiop_debug & DEBUG_DISC) {
                        printf("%s: ID %02x disconnected TEMP %x (+%lx) "
                            "curaddr %lx curlen %lx buf %x len %x dfifo %x "
                            "dbc %x sstat1 %x starts %d acb %p\n",
                            device_xname(sc->sc_dev), 1 << target,
                            osiop_read_4(sc, OSIOP_TEMP),
                            (osiop_read_4(sc, OSIOP_TEMP) != 0) ?
                                osiop_read_4(sc, OSIOP_TEMP) - scraddr : 0,
                            acb->curaddr, acb->curlen,
                            ds->data[0].addr, ds->data[0].count,
                            dfifo, dbc, sstat1, osiopstarts, acb);
                        bus_dmamap_sync(sc->sc_dmat, dsdma,
                            acb->dsoffset, sizeof(struct osiop_ds),
                            BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
                }
#endif
                /*
                 * XXXX need to update curaddr/curlen to reflect
                 * current data transferred.  If device disconnected in
                 * the middle of a DMA block, they should already be set
                 * by the phase change interrupt.  If the disconnect
                 * occurs on a DMA block boundary, we have to figure out
                 * which DMA block it was.
                 */
                if (acb->datalen > 0 &&
                    osiop_read_4(sc, OSIOP_TEMP) != 0) {
                        long n = osiop_read_4(sc, OSIOP_TEMP) - scraddr;

                        if (acb->curlen != 0 &&
                            acb->curlen != ds->data[0].count)
                                printf("%s: curaddr/curlen already set? "
                                    "n %lx iob %lx/%lx chain[0] %x/%x\n",
                                    device_xname(sc->sc_dev), n,
                                    acb->curaddr, acb->curlen,
                                    ds->data[0].addr, ds->data[0].count);
                        if (n < Ent_datain)
                                n = (n - Ent_dataout) / 16;
                        else
                                n = (n - Ent_datain) / 16;
                        if (n < 0 || n >= OSIOP_NSG)
                                printf("TEMP invalid %ld\n", n);
                        else {
                                acb->curaddr = ds->data[n].addr;
                                acb->curlen = ds->data[n].count;
                        }
#ifdef OSIOP_DEBUG
                        if (osiop_debug & DEBUG_DISC) {
                                printf("%s: TEMP offset %ld",
                                    device_xname(sc->sc_dev), n);
                                printf(" curaddr %lx curlen %lx\n",
                                    acb->curaddr, acb->curlen);
                        }
#endif
                }
                /*
                 * If data transfer was interrupted by disconnect, curaddr
                 * and curlen should reflect the point of interruption.
                 * Adjust the DMA chain so that the data transfer begins
                 * at the appropriate place upon reselection.
                 * XXX This should only be done on save data pointer message?
                 */
                if (acb->curlen > 0) {
                        int i, j;

#ifdef OSIOP_DEBUG
                        if (osiop_debug & DEBUG_DISC)
                                printf("%s: adjusting DMA chain\n",
                                    device_xname(sc->sc_dev));
                        if (intcode == A_int_disc_wodp)
                                printf("%s: ID %02x disconnected "
                                    "without Save Data Pointers\n",
                                    device_xname(sc->sc_dev), 1 << target);
#endif
                        for (i = 0; i < OSIOP_NSG; i++) {
                                if (ds->data[i].count == 0)
                                        break;
                                if (acb->curaddr >= ds->data[i].addr &&
                                    acb->curaddr <
                                    (ds->data[i].addr + ds->data[i].count))
                                        break;
                        }
                        if (i >= OSIOP_NSG || ds->data[i].count == 0) {
                                printf("couldn't find saved data pointer: "
                                    "curaddr %lx curlen %lx i %d\n",
                                    acb->curaddr, acb->curlen, i);
#ifdef DDB
                                Debugger();
#endif
                        }
#ifdef OSIOP_DEBUG
                        if (osiop_debug & DEBUG_DISC)
                                printf(" chain[0]: %x/%x -> %lx/%lx\n",
                                    ds->data[0].addr, ds->data[0].count,
                                    acb->curaddr, acb->curlen);
#endif
                        ds->data[0].addr = acb->curaddr;
                        ds->data[0].count = acb->curlen;
                        for (j = 1, i = i + 1;
                            i < OSIOP_NSG && ds->data[i].count > 0;
                            i++, j++) {
#ifdef OSIOP_DEBUG
                                if (osiop_debug & DEBUG_DISC)
                                        printf("  chain[%d]: %x/%x -> %x/%x\n",
                                            j, ds->data[j].addr,
                                            ds->data[j].count,
                                            ds->data[i].addr,
                                            ds->data[i].count);
#endif
                                ds->data[j].addr  = ds->data[i].addr;
                                ds->data[j].count = ds->data[i].count;
                        }
                        if (j < OSIOP_NSG) {
                                ds->data[j].addr  = 0;
                                ds->data[j].count = 0;
                        }
                        bus_dmamap_sync(sc->sc_dmat, dsdma,
                            acb->dsoffset, sizeof(struct osiop_ds),
                            BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
                }
                sc->sc_tinfo[target].dconns++;
                /*
                 * add nexus to waiting list
                 * clear nexus
                 * try to start another command for another target/lun
                 */
                acb->intstat = sc->sc_flags & OSIOP_INTSOFF;
                TAILQ_INSERT_TAIL(&sc->nexus_list, acb, chain);
                sc->sc_nexus = NULL;            /* no current device */
                osiop_write_4(sc, OSIOP_DSP, scraddr + Ent_wait_reselect);
                /* XXXX start another command ? */
                if (!TAILQ_EMPTY(&sc->ready_list))
                        osiop_sched(sc);
                return (0);
        }
        if (dstat & OSIOP_DSTAT_SIR && intcode == A_int_reconnect) {
                int reselid = ffs(osiop_read_4(sc, OSIOP_SCRATCH) & 0xff) - 1;
                int reselun = osiop_read_1(sc, OSIOP_SFBR) & 0x07;
#ifdef OSIOP_DEBUG
                uint8_t resmsg;
#endif

                /* Reconnect */
                /* XXXX save current SBCL */
                sc->sc_sstat1 = osiop_read_1(sc, OSIOP_SBCL);
#ifdef OSIOP_DEBUG
                if (osiop_debug & DEBUG_DISC)
                        printf("%s: target ID %02x reselected dsps %x\n",
                            device_xname(sc->sc_dev), reselid, intcode);
                resmsg = osiop_read_1(sc, OSIOP_SFBR);
                if (!MSG_ISIDENTIFY(resmsg))
                        printf("%s: Reselect message in was not identify: "
                            "%02x\n", device_xname(sc->sc_dev), resmsg);
#endif
                if (sc->sc_nexus != NULL) {
                        struct scsipi_periph *periph =
                            sc->sc_nexus->xs->xs_periph;
#ifdef OSIOP_DEBUG
                        if (osiop_debug & DEBUG_DISC)
                                printf("%s: reselect ID %02x w/active\n",
                                    device_xname(sc->sc_dev), reselid);
#endif
                        TAILQ_INSERT_HEAD(&sc->ready_list,
                            sc->sc_nexus, chain);
                        sc->sc_tinfo[periph->periph_target].lubusy
                            &= ~(1 << periph->periph_lun);
                        sc->sc_active--;
                }
                /*
                 * locate acb of reselecting device
                 * set sc->sc_nexus to acb
                 */
                TAILQ_FOREACH(acb, &sc->nexus_list, chain) {
                        struct scsipi_periph *periph = acb->xs->xs_periph;
                        if (reselid != periph->periph_target ||
                            reselun != periph->periph_lun) {
                                continue;
                        }
                        TAILQ_REMOVE(&sc->nexus_list, acb, chain);
                        sc->sc_nexus = acb;
                        sc->sc_flags |= acb->intstat;
                        acb->intstat = 0;
                        osiop_write_4(sc, OSIOP_DSA,
                            dsdma->dm_segs[0].ds_addr + acb->dsoffset);
                        osiop_write_1(sc, OSIOP_SXFER,
                            sc->sc_tinfo[reselid].sxfer);
                        osiop_write_1(sc, OSIOP_SBCL,
                            sc->sc_tinfo[reselid].sbcl);
                        break;
                }
                if (acb == NULL) {
                        printf("%s: target ID %02x reselect nexus_list %p\n",
                            device_xname(sc->sc_dev), reselid,
                            TAILQ_FIRST(&sc->nexus_list));
                        panic("unable to find reselecting device");
                }

                osiop_write_4(sc, OSIOP_TEMP, 0);
                osiop_write_1(sc, OSIOP_DCNTL,
                    osiop_read_1(sc, OSIOP_DCNTL) | OSIOP_DCNTL_STD);
                return (0);
        }
        if (dstat & OSIOP_DSTAT_SIR && intcode == A_int_connect) {
#ifdef OSIOP_DEBUG
                uint8_t ctest2 = osiop_read_1(sc, OSIOP_CTEST2);

                /* reselect was interrupted (by Sig_P or select) */
                if (osiop_debug & DEBUG_DISC ||
                    (ctest2 & OSIOP_CTEST2_SIGP) == 0)
                        printf("%s: reselect interrupted (Sig_P?) "
                            "scntl1 %x ctest2 %x sfbr %x istat %x/%x\n",
                            device_xname(sc->sc_dev),
                            osiop_read_1(sc, OSIOP_SCNTL1), ctest2,
                            osiop_read_1(sc, OSIOP_SFBR), istat,
                            osiop_read_1(sc, OSIOP_ISTAT));
#endif
                /* XXX assumes it was not select */
                if (sc->sc_nexus == NULL) {
#ifdef OSIOP_DEBUG
                        printf("%s: reselect interrupted, sc_nexus == NULL\n",
                            device_xname(sc->sc_dev));
#if 0
                        osiop_dump(sc);
#ifdef DDB
                        Debugger();
#endif
#endif
#endif
                        osiop_write_1(sc, OSIOP_DCNTL,
                            osiop_read_1(sc, OSIOP_DCNTL) | OSIOP_DCNTL_STD);
                        return (0);
                }
                target = sc->sc_nexus->xs->xs_periph->periph_target;
                osiop_write_4(sc, OSIOP_TEMP, 0);
                osiop_write_4(sc, OSIOP_DSA,
                    dsdma->dm_segs[0].ds_addr + sc->sc_nexus->dsoffset);
                osiop_write_1(sc, OSIOP_SXFER, sc->sc_tinfo[target].sxfer);
                osiop_write_1(sc, OSIOP_SBCL, sc->sc_tinfo[target].sbcl);
                osiop_write_4(sc, OSIOP_DSP, scraddr + Ent_scripts);
                return (0);
        }
        if (dstat & OSIOP_DSTAT_SIR && intcode == A_int_msgin) {
                /* Unrecognized message in byte */
                if (acb == NULL) {
                        printf("%s: Bad message-in with no active command?\n",
                            device_xname(sc->sc_dev));
                        goto bad_phase;
                }
                printf("%s: Unrecognized message in data "
                    "sfbr %x msg %x sbcl %x\n", device_xname(sc->sc_dev),
                    osiop_read_1(sc, OSIOP_SFBR), ds->msgbuf[1],
                    osiop_read_1(sc, OSIOP_SBCL));
                /* what should be done here? */
                osiop_write_4(sc, OSIOP_DSP, scraddr + Ent_clear_ack);
                bus_dmamap_sync(sc->sc_dmat, dsdma,
                    acb->dsoffset, sizeof(struct osiop_ds),
                    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
                return (0);
        }
        if (dstat & OSIOP_DSTAT_SIR && intcode == A_int_status) {
                /* Status phase wasn't followed by message in phase? */
                printf("%s: Status phase not followed by message in phase? "
                    "sbcl %x sbdl %x\n", device_xname(sc->sc_dev),
                    osiop_read_1(sc, OSIOP_SBCL),
                    osiop_read_1(sc, OSIOP_SBDL));
                if (osiop_read_1(sc, OSIOP_SBCL) == 0xa7) {
                        /* It is now, just continue the script? */
                        osiop_write_1(sc, OSIOP_DCNTL,
                            osiop_read_1(sc, OSIOP_DCNTL) | OSIOP_DCNTL_STD);
                        return (0);
                }
        }
        if (dstat & OSIOP_DSTAT_SIR && sstat0 == 0) {
                printf("OSIOP interrupt: %x sts %x msg %x %x sbcl %x\n",
                    intcode, ds->stat[0], ds->msgbuf[0], ds->msgbuf[1],
                    osiop_read_1(sc, OSIOP_SBCL));
                osiop_reset(sc);
                *status = SCSI_OSIOP_NOSTATUS;
                return (0);     /* osiop_reset has cleaned up */
        }
        if (sstat0 & OSIOP_SSTAT0_SGE)
                printf("%s: SCSI Gross Error\n", device_xname(sc->sc_dev));
        if (sstat0 & OSIOP_SSTAT0_PAR)
                printf("%s: Parity Error\n", device_xname(sc->sc_dev));
        if (dstat & OSIOP_DSTAT_IID)
                printf("%s: Invalid instruction detected\n",
                    device_xname(sc->sc_dev));
 bad_phase:
        /*
         * temporary panic for unhandled conditions
         * displays various things about the 53C710 status and registers
         * then panics.
         * XXXX need to clean this up to print out the info, reset, and continue
         */
        printf("osiop_chkintr: target %x ds %p\n", target, ds);
        printf("scripts %lx ds %lx dsp %x dcmd %x\n", scraddr,
            acb ? sc->sc_dsdma->dm_segs[0].ds_addr + acb->dsoffset : 0,
            osiop_read_4(sc, OSIOP_DSP),
            osiop_read_4(sc, OSIOP_DBC));
        printf("osiop_chkintr: istat %x dstat %x sstat0 %x "
            "dsps %x dsa %x sbcl %x sts %x msg %x %x sfbr %x\n",
            istat, dstat, sstat0, intcode,
            osiop_read_4(sc, OSIOP_DSA),
            osiop_read_1(sc, OSIOP_SBCL),
            ds ? ds->stat[0] : 0,
            ds ? ds->msgbuf[0] : 0,
            ds ? ds->msgbuf[1] : 0,
            osiop_read_1(sc, OSIOP_SFBR));
#ifdef OSIOP_DEBUG
        if (osiop_debug & DEBUG_DMA)
                panic("osiop_chkintr: **** temp ****");
#ifdef DDB
        Debugger();
#endif
#endif
        osiop_reset(sc);        /* hard reset */
        *status = SCSI_OSIOP_NOSTATUS;
        if (acb != NULL)
                acb->status = ACB_S_DONE;
        return (0);             /* osiop_reset cleaned up */
}

void
osiop_select(struct osiop_softc *sc)
{
        struct osiop_acb *acb = sc->sc_nexus;

#ifdef OSIOP_DEBUG
        if (osiop_debug & DEBUG_CMD)
                printf("%s: select ", device_xname(sc->sc_dev));
#endif

        if (acb->xs->xs_control & XS_CTL_POLL || sc->sc_flags & OSIOP_NODMA) {
                sc->sc_flags |= OSIOP_INTSOFF;
                sc->sc_flags &= ~OSIOP_INTDEFER;
                if ((osiop_read_1(sc, OSIOP_ISTAT) & OSIOP_ISTAT_CON) == 0) {
                        osiop_write_1(sc, OSIOP_SIEN, 0);
                        osiop_write_1(sc, OSIOP_DIEN, 0);
                }
#if 0
        } else if ((sc->sc_flags & OSIOP_INTDEFER) == 0) {
                sc->sc_flags &= ~OSIOP_INTSOFF;
                if ((osiop_read_1(sc, OSIOP_ISTAT) & OSIOP_ISTAT_CON) == 0) {
                        osiop_write_1(sc, OSIOP_SIEN, sc->sc_sien);
                        osiop_write_1(sc, OSIOP_DIEN, sc->sc_dien);
                }
#endif
        }
#ifdef OSIOP_DEBUG
        if (osiop_debug & DEBUG_CMD)
                printf("osiop_select: target %x cmd %02x ds %p\n",
                    acb->xs->xs_periph->periph_target,
                    acb->xs->cmd->opcode, sc->sc_nexus->ds);
#endif

        osiop_start(sc);

        return;
}

/*
 * 53C710 interrupt handler
 */

void
osiop_intr(struct osiop_softc *sc)
{
        int status, s;
        uint8_t istat, dstat, sstat0;

        s = splbio();

        istat = sc->sc_istat;
        if ((istat & (OSIOP_ISTAT_SIP | OSIOP_ISTAT_DIP)) == 0) {
                splx(s);
                return;
        }

        /* Got a valid interrupt on this device; set by MD handler */
        dstat = sc->sc_dstat;
        sstat0 = sc->sc_sstat0;
        sc->sc_istat = 0;
#ifdef OSIOP_DEBUG
        if (!sc->sc_active) {
                /* XXX needs sync */
                printf("%s: spurious interrupt? "
                    "istat %x dstat %x sstat0 %x nexus %p status %x\n",
                    device_xname(sc->sc_dev),
                    istat, dstat, sstat0, sc->sc_nexus,
                    (sc->sc_nexus != NULL) ? sc->sc_nexus->ds->stat[0] : 0);
        }
#endif

#ifdef OSIOP_DEBUG
        if (osiop_debug & (DEBUG_INT|DEBUG_CMD)) {
                /* XXX needs sync */
                printf("%s: intr istat %x dstat %x sstat0 %x dsps %x "
                    "sbcl %x dsp %x dcmd %x sts %x msg %x\n",
                    device_xname(sc->sc_dev),
                    istat, dstat, sstat0,
                    osiop_read_4(sc, OSIOP_DSPS),
                    osiop_read_1(sc, OSIOP_SBCL),
                    osiop_read_4(sc, OSIOP_DSP),
                    osiop_read_4(sc, OSIOP_DBC),
                    (sc->sc_nexus != NULL) ? sc->sc_nexus->ds->stat[0] : 0,
                    (sc->sc_nexus != NULL) ? sc->sc_nexus->ds->msgbuf[0] : 0);
        }
#endif
        if (sc->sc_flags & OSIOP_INTDEFER) {
                sc->sc_flags &= ~(OSIOP_INTDEFER | OSIOP_INTSOFF);
                osiop_write_1(sc, OSIOP_SIEN, sc->sc_sien);
                osiop_write_1(sc, OSIOP_DIEN, sc->sc_dien);
        }
        if (osiop_checkintr(sc, istat, dstat, sstat0, &status)) {
#if 0
                if (status == SCSI_OSIOP_NOSTATUS)
                        printf("osiop_intr: no valid status \n");
#endif
                if ((sc->sc_flags & (OSIOP_INTSOFF | OSIOP_INTDEFER)) !=
                    OSIOP_INTSOFF) {
#if 0
                        if (osiop_read_1(sc, OSIOP_SBCL) & OSIOP_BSY) {
                                struct scsipi_periph *periph;

                                periph = sc->sc_nexus->xs->xs_periph;
                                printf("%s: SCSI bus busy at completion"
                                    " targ %d sbcl %02x sfbr %x lcrc "
                                    "%02x dsp +%x\n", device_xname(sc->sc_dev),
                                    periph->periphtarget,
                                    osiop_read_1(sc, OSIOP_SBCL),
                                    osiop_read_1(sc, OSIOP_SFBR),
                                    osiop_read_1(sc, OSIOP_LCRC),
                                    osiop_read_4(sc, OSIOP_DSP) -
                                        sc->sc_scrdma->dm_segs[0].ds_addr);
                        }
#endif
                        osiop_scsidone(sc->sc_nexus, status);
                }
        }
        splx(s);
}

void
osiop_update_xfer_mode(struct osiop_softc *sc, int target)
{
        struct osiop_tinfo *tinfo = &sc->sc_tinfo[target];
        struct scsipi_xfer_mode xm;

        xm.xm_target = target;
        xm.xm_mode = 0;
        xm.xm_period = 0;
        xm.xm_offset = 0;

        if (tinfo->period) {
                xm.xm_mode |= PERIPH_CAP_SYNC;
                xm.xm_period = tinfo->period;
                xm.xm_offset = tinfo->offset;
        }

        scsipi_async_event(&sc->sc_channel, ASYNC_EVENT_XFER_MODE, &xm);
}

void
scsi_period_to_osiop(struct osiop_softc *sc, int target)
{
        int period, offset, sxfer, sbcl;

        period = sc->sc_tinfo[target].period;
        offset = sc->sc_tinfo[target].offset;
        for (sbcl = 1; sbcl < 4; sbcl++) {
                sxfer = (period * 4 - 1) / sc->sc_tcp[sbcl] - 3;
                if (sxfer >= 0 && sxfer <= 7)
                        break;
        }
        if (sbcl > 3) {
                printf("osiop sync: unable to compute sync params "
                    "for period %d ns\n", period * 4);
                /*
                 * XXX need to pick a value we can do and renegotiate
                 */
                sxfer = sbcl = 0;
        } else {
                sxfer = (sxfer << 4) | ((offset <= OSIOP_MAX_OFFSET) ?
                    offset : OSIOP_MAX_OFFSET);
#ifdef DEBUG_SYNC
                printf("osiop sync: params for period %dns: sxfer %x sbcl %x",
                    period * 4, sxfer, sbcl);
                printf(" actual period %dns\n",
                    sc->sc_tcp[sbcl] * ((sxfer >> 4) + 4));
#endif
        }
        sc->sc_tinfo[target].sxfer = sxfer;
        sc->sc_tinfo[target].sbcl = sbcl;
#ifdef DEBUG_SYNC
        printf("osiop sync: osiop_sxfr %02x, osiop_sbcl %02x\n", sxfer, sbcl);
#endif
}

void
osiop_timeout(void *arg)
{
        struct osiop_acb *acb = arg;
        struct scsipi_xfer *xs = acb->xs;
        struct osiop_softc *sc = acb->sc;
        int s;

        scsipi_printaddr(xs->xs_periph);
        printf("command timeout\n");

        s = splbio();
        /* reset the scsi bus */
        osiop_resetbus(sc);

        /* deactivate callout */
        callout_stop(&xs->xs_callout);
        acb->flags |= ACB_F_TIMEOUT;
        osiop_reset(sc);
        splx(s);
        return;
}

#ifdef OSIOP_DEBUG

#if OSIOP_TRACE_SIZE
void
osiop_dump_trace(void)
{
        int i;

        printf("osiop trace: next index %d\n", osiop_trix);
        i = osiop_trix;
        do {
                printf("%3d: '%c' %02x %02x %02x\n", i,
                    osiop_trbuf[i], osiop_trbuf[i + 1],
                    osiop_trbuf[i + 2], osiop_trbuf[i + 3]);
                i = (i + 4) & (OSIOP_TRACE_SIZE - 1);
        } while (i != osiop_trix);
}
#endif

void
osiop_dump_acb(struct osiop_acb *acb)
{
        uint8_t *b;
        int i;

        printf("acb@%p ", acb);
        if (acb->xs == NULL) {
                printf("<unused>\n");
                return;
        }

        b = (uint8_t *)&acb->xs->cmd;
        printf("(%d:%d) status %2x cmdlen %2ld cmd ",
            acb->xs->xs_periph->periph_target,
            acb->xs->xs_periph->periph_lun, acb->status, acb->cmdlen);
        for (i = acb->cmdlen; i > 0; i--)
                printf(" %02x", *b++);
        printf("\n");
        printf("  xs: %p data %p:%04x ", acb->xs, acb->xs->data,
            acb->xs->datalen);
        printf("va %p:%lx ", acb->data, acb->datalen);
        printf("cur %lx:%lx\n", acb->curaddr, acb->curlen);
}

void
osiop_dump(struct osiop_softc *sc)
{
        struct osiop_acb *acb;
        int i, s;

        s = splbio();
#if OSIOP_TRACE_SIZE
        osiop_dump_trace();
#endif
        printf("%s@%p istat %02x\n",
            device_xname(sc->sc_dev), sc, osiop_read_1(sc, OSIOP_ISTAT));
        if ((acb = TAILQ_FIRST(&sc->free_list)) != NULL) {
                printf("Free list:\n");
                while (acb) {
                        osiop_dump_acb(acb);
                        acb = TAILQ_NEXT(acb, chain);
                }
        }
        if ((acb = TAILQ_FIRST(&sc->ready_list)) != NULL) {
                printf("Ready list:\n");
                while (acb) {
                        osiop_dump_acb(acb);
                        acb = TAILQ_NEXT(acb, chain);
                }
        }
        if ((acb = TAILQ_FIRST(&sc->nexus_list)) != NULL) {
                printf("Nexus list:\n");
                while (acb) {
                        osiop_dump_acb(acb);
                        acb = TAILQ_NEXT(acb, chain);
                }
        }
        if (sc->sc_nexus) {
                printf("Nexus:\n");
                osiop_dump_acb(sc->sc_nexus);
        }
        for (i = 0; i < OSIOP_NTGT; i++) {
                if (sc->sc_tinfo[i].cmds > 2) {
                        printf("tgt %d: cmds %d disc %d lubusy %x\n",
                            i, sc->sc_tinfo[i].cmds,
                            sc->sc_tinfo[i].dconns,
                            sc->sc_tinfo[i].lubusy);
                }
        }
        splx(s);
}
#endif