Expand PMF_FN_* macros.

[netbsd-mini2440.git] / sys / dev / ic / aic6360.c

/*      $NetBSD: aic6360.c,v 1.98 2009/11/12 19:25:08 dyoung Exp $      */

/*
 * Copyright (c) 1994, 1995, 1996 Charles M. Hannum.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Charles M. Hannum.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * Copyright (c) 1994 Jarle Greipsland
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * 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.
 */

/*
 * Acknowledgements: Many of the algorithms used in this driver are
 * inspired by the work of Julian Elischer (julian@tfs.com) and
 * Charles Hannum (mycroft@duality.gnu.ai.mit.edu).  Thanks a million!
 */

/* TODO list:
 * 1) Get the DMA stuff working.
 * 2) Get the iov/uio stuff working. Is this a good thing ???
 * 3) Get the synch stuff working.
 * 4) Rewrite it to use malloc for the acb structs instead of static alloc.?
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: aic6360.c,v 1.98 2009/11/12 19:25:08 dyoung Exp $");

#include "opt_ddb.h"

/*
 * A few customizable items:
 */

/* Use doubleword transfers to/from SCSI chip.  Note: This requires
 * motherboard support.  Basicly, some motherboard chipsets are able to
 * split a 32 bit I/O operation into two 16 bit I/O operations,
 * transparently to the processor.  This speeds up some things, notably long
 * data transfers.
 */
#define AIC_USE_DWORDS          0

/* Synchronous data transfers? */
#define AIC_USE_SYNCHRONOUS     0
#define AIC_SYNC_REQ_ACK_OFS    8

/* Wide data transfers? */
#define AIC_USE_WIDE            0
#define AIC_MAX_WIDTH           0

/* Max attempts made to transmit a message */
#define AIC_MSG_MAX_ATTEMPT     3 /* Not used now XXX */

/* Use DMA (else we do programmed I/O using string instructions) (not yet!)*/
#define AIC_USE_EISA_DMA        0
#define AIC_USE_ISA_DMA         0

/* How to behave on the (E)ISA bus when/if DMAing (on<<4) + off in us */
#define EISA_BRST_TIM ((15<<4) + 1)     /* 15us on, 1us off */

/* Some spin loop parameters (essentially how long to wait some places)
 * The problem(?) is that sometimes we expect either to be able to transmit a
 * byte or to get a new one from the SCSI bus pretty soon.  In order to avoid
 * returning from the interrupt just to get yanked back for the next byte we
 * may spin in the interrupt routine waiting for this byte to come.  How long?
 * This is really (SCSI) device and processor dependent.  Tuneable, I guess.
 */
#define AIC_MSGIN_SPIN          1       /* Will spinwait upto ?ms for a new msg byte */
#define AIC_MSGOUT_SPIN         1

/* Include debug functions?  At the end of this file there are a bunch of
 * functions that will print out various information regarding queued SCSI
 * commands, driver state and chip contents.  You can call them from the
 * kernel debugger.  If you set AIC_DEBUG to 0 they are not included (the
 * kernel uses less memory) but you lose the debugging facilities.
 */
#define AIC_DEBUG               1

#define AIC_ABORT_TIMEOUT       2000    /* time to wait for abort */

/* End of customizable parameters */

#if AIC_USE_EISA_DMA || AIC_USE_ISA_DMA
#error "I said not yet! Start paying attention... grumble"
#endif

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/callout.h>
#include <sys/kernel.h>
#include <sys/errno.h>
#include <sys/ioctl.h>
#include <sys/device.h>
#include <sys/buf.h>
#include <sys/proc.h>
#include <sys/queue.h>

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

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

#include <dev/ic/aic6360reg.h>
#include <dev/ic/aic6360var.h>

#ifndef DDB
#define Debugger() panic("should call debugger here (aic6360.c)")
#endif /* ! DDB */

#if AIC_DEBUG
int aic_debug = 0x00; /* AIC_SHOWSTART|AIC_SHOWMISC|AIC_SHOWTRACE; */
#endif

static void     aic_minphys(struct buf *);
static void     aic_done(struct aic_softc *, struct aic_acb *);
static void     aic_dequeue(struct aic_softc *, struct aic_acb *);
static void     aic_scsipi_request(struct scsipi_channel *,
                                   scsipi_adapter_req_t, void *);
static int      aic_poll(struct aic_softc *, struct scsipi_xfer *, int);
static void     aic_select(struct aic_softc *, struct aic_acb *);
static void     aic_timeout(void *);
static void     aic_sched(struct aic_softc *);
static void     aic_scsi_reset(struct aic_softc *);
static void     aic_reset(struct aic_softc *);
static void     aic_free_acb(struct aic_softc *, struct aic_acb *);
static struct aic_acb* aic_get_acb(struct aic_softc *);
static int      aic_reselect(struct aic_softc *, int);
static void     aic_sense(struct aic_softc *, struct aic_acb *);
static void     aic_msgin(struct aic_softc *);
static void     aic_abort(struct aic_softc *, struct aic_acb *);
static void     aic_msgout(struct aic_softc *);
static int      aic_dataout_pio(struct aic_softc *, u_char *, int);
static int      aic_datain_pio(struct aic_softc *, u_char *, int);
static void     aic_update_xfer_mode(struct aic_softc *, int);
#if AIC_DEBUG
static void     aic_print_acb(struct aic_acb *);
void    aic_dump_driver(struct aic_softc *);
void    aic_dump6360(struct aic_softc *);
static void     aic_show_scsi_cmd(struct aic_acb *);
void    aic_print_active_acb(void);
#endif

/*
 * INITIALIZATION ROUTINES (probe, attach ++)
 */

/* Do the real search-for-device.
 * Prerequisite: sc->sc_iobase should be set to the proper value
 */
int
aic_find(bus_space_tag_t iot, bus_space_handle_t ioh)
{
        char chip_id[sizeof(IDSTRING)]; /* For chips that support it */
        int i;

        /* Remove aic6360 from possible powerdown mode */
        bus_space_write_1(iot, ioh, DMACNTRL0, 0);

        /* Thanks to mark@aggregate.com for the new method for detecting
         * whether the chip is present or not.  Bonus: may also work for
         * the AIC-6260!
         */
        AIC_TRACE(("aic: probing for aic-chip\n"));
        /*
         * Linux also init's the stack to 1-16 and then clears it,
         *  6260's don't appear to have an ID reg - mpg
         */
        /* Push the sequence 0,1,..,15 on the stack */
#define STSIZE 16
        bus_space_write_1(iot, ioh, DMACNTRL1, 0); /* Reset stack pointer */
        for (i = 0; i < STSIZE; i++)
                bus_space_write_1(iot, ioh, STACK, i);

        /* See if we can pull out the same sequence */
        bus_space_write_1(iot, ioh, DMACNTRL1, 0);
        for (i = 0; i < STSIZE && bus_space_read_1(iot, ioh, STACK) == i; i++)
                ;
        if (i != STSIZE) {
                AIC_START(("STACK futzed at %d.\n", i));
                return 0;
        }

        /* See if we can pull the id string out of the ID register,
         * now only used for informational purposes.
         */
        memset(chip_id, 0, sizeof(chip_id));
        bus_space_read_multi_1(iot, ioh, ID, chip_id, sizeof(IDSTRING) - 1);
        AIC_START(("AIC found ID: %s ",chip_id));
        AIC_START(("chip revision %d\n",
            (int)bus_space_read_1(iot, ioh, REV)));

        return 1;
}

/*
 * Attach the AIC6360, fill out some high and low level data structures
 */
void
aicattach(struct aic_softc *sc)
{
        struct scsipi_adapter *adapt = &sc->sc_adapter;
        struct scsipi_channel *chan = &sc->sc_channel;

        AIC_TRACE(("aicattach  "));
        sc->sc_state = AIC_INIT;

        sc->sc_initiator = 7;
        sc->sc_freq = 20;       /* XXXX Assume 20 MHz. */

        /*
         * These are the bounds of the sync period, based on the frequency of
         * the chip's clock input and the size and offset of the sync period
         * register.
         *
         * For a 20MHz clock, this gives us 25, or 100nS, or 10MB/s, as a
         * maximum transfer rate, and 112.5, or 450nS, or 2.22MB/s, as a
         * minimum transfer rate.
         */
        sc->sc_minsync = (2 * 250) / sc->sc_freq;
        sc->sc_maxsync = (9 * 250) / sc->sc_freq;

        /*
         * Fill in the scsipi_adapter.
         */
        adapt->adapt_dev = sc->sc_dev;
        adapt->adapt_nchannels = 1;
        adapt->adapt_openings = 8;
        adapt->adapt_max_periph = 1;
        adapt->adapt_request = aic_scsipi_request;
        adapt->adapt_minphys = aic_minphys;

        /*
         * Fill in the scsipi_channel.
         */
        chan->chan_adapter = adapt;
        chan->chan_bustype = &scsi_bustype;
        chan->chan_channel = 0;
        chan->chan_ntargets = 8;
        chan->chan_nluns = 8;
        chan->chan_id = sc->sc_initiator;

        /*
         * Add reference to adapter so that we drop the reference after
         * config_found() to make sure the adatper is disabled.
         */
        if (scsipi_adapter_addref(adapt) != 0) {
                aprint_error_dev(sc->sc_dev, "unable to enable controller\n");
                return;
        }

        aic_init(sc, 1);        /* Init chip and driver */

        /*
         * Ask the adapter what subunits are present
         */
        sc->sc_child = config_found(sc->sc_dev, &sc->sc_channel, scsiprint);
        scsipi_adapter_delref(adapt);
}

int
aic_detach(device_t self, int flags)
{
        struct aic_softc *sc = device_private(self);
        int rv = 0;

        if (sc->sc_child != NULL)
                rv = config_detach(sc->sc_child, flags);

        return (rv);
}

/* Initialize AIC6360 chip itself
 * The following conditions should hold:
 * aic_isa_probe should have succeeded, i.e. the iobase address in aic_softc
 * must be valid.
 */
static void
aic_reset(struct aic_softc *sc)
{
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;

        /*
         * Doc. recommends to clear these two registers before
         * operations commence
         */
        bus_space_write_1(iot, ioh, SCSITEST, 0);
        bus_space_write_1(iot, ioh, TEST, 0);

        /* Reset SCSI-FIFO and abort any transfers */
        bus_space_write_1(iot, ioh, SXFRCTL0, CHEN | CLRCH | CLRSTCNT);

        /* Reset DMA-FIFO */
        bus_space_write_1(iot, ioh, DMACNTRL0, RSTFIFO);
        bus_space_write_1(iot, ioh, DMACNTRL1, 0);

        /* Disable all selection features */
        bus_space_write_1(iot, ioh, SCSISEQ, 0);
        bus_space_write_1(iot, ioh, SXFRCTL1, 0);

        /* Disable some interrupts */
        bus_space_write_1(iot, ioh, SIMODE0, 0x00);
        /* Clear a slew of interrupts */
        bus_space_write_1(iot, ioh, CLRSINT0, 0x7f);

        /* Disable some more interrupts */
        bus_space_write_1(iot, ioh, SIMODE1, 0x00);
        /* Clear another slew of interrupts */
        bus_space_write_1(iot, ioh, CLRSINT1, 0xef);

        /* Disable synchronous transfers */
        bus_space_write_1(iot, ioh, SCSIRATE, 0);

        /* Haven't seen ant errors (yet) */
        bus_space_write_1(iot, ioh, CLRSERR, 0x07);

        /* Set our SCSI-ID */
        bus_space_write_1(iot, ioh, SCSIID, sc->sc_initiator << OID_S);
        bus_space_write_1(iot, ioh, BRSTCNTRL, EISA_BRST_TIM);
}

/* Pull the SCSI RST line for 500 us */
static void
aic_scsi_reset(struct aic_softc *sc)
{
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;

        bus_space_write_1(iot, ioh, SCSISEQ, SCSIRSTO);
        delay(500);
        bus_space_write_1(iot, ioh, SCSISEQ, 0);
        delay(50);
}

/*
 * Initialize aic SCSI driver.
 */
void
aic_init(struct aic_softc *sc, int bus_reset)
{
        struct aic_acb *acb;
        int r;

        if (bus_reset) {
                aic_reset(sc);
                aic_scsi_reset(sc);
        }
        aic_reset(sc);

        if (sc->sc_state == AIC_INIT) {
                /* First time through; initialize. */
                TAILQ_INIT(&sc->ready_list);
                TAILQ_INIT(&sc->nexus_list);
                TAILQ_INIT(&sc->free_list);
                sc->sc_nexus = NULL;
                acb = sc->sc_acb;
                memset(acb, 0, sizeof(sc->sc_acb));
                for (r = 0; r < sizeof(sc->sc_acb) / sizeof(*acb); r++) {
                        TAILQ_INSERT_TAIL(&sc->free_list, acb, chain);
                        acb++;
                }
                memset(&sc->sc_tinfo, 0, sizeof(sc->sc_tinfo));
        } else {
                /* Cancel any active commands. */
                sc->sc_state = AIC_CLEANING;
                if ((acb = sc->sc_nexus) != NULL) {
                        acb->xs->error = XS_DRIVER_STUFFUP;
                        callout_stop(&acb->xs->xs_callout);
                        aic_done(sc, acb);
                }
                while ((acb = sc->nexus_list.tqh_first) != NULL) {
                        acb->xs->error = XS_DRIVER_STUFFUP;
                        callout_stop(&acb->xs->xs_callout);
                        aic_done(sc, acb);
                }
        }

        sc->sc_prevphase = PH_INVALID;
        for (r = 0; r < 8; r++) {
                struct aic_tinfo *ti = &sc->sc_tinfo[r];

                ti->flags = 0;
                ti->period = ti->offset = 0;
                ti->width = 0;
        }

        sc->sc_state = AIC_IDLE;
        bus_space_write_1(sc->sc_iot, sc->sc_ioh, DMACNTRL0, INTEN);
}

static void
aic_free_acb(struct aic_softc *sc, struct aic_acb *acb)
{
        int s;

        s = splbio();
        acb->flags = 0;
        TAILQ_INSERT_HEAD(&sc->free_list, acb, chain);
        splx(s);
}

static struct aic_acb *
aic_get_acb(struct aic_softc *sc)
{
        struct aic_acb *acb;
        int s;

        s = splbio();
        acb = TAILQ_FIRST(&sc->free_list);
        if (acb != NULL) {
                TAILQ_REMOVE(&sc->free_list, acb, chain);
                acb->flags |= ACB_ALLOC;
        }
        splx(s);
        return (acb);
}

/*
 * DRIVER FUNCTIONS CALLABLE FROM HIGHER LEVEL DRIVERS
 */

/*
 * Expected sequence:
 * 1) Command inserted into ready list
 * 2) Command selected for execution
 * 3) Command won arbitration and has selected target device
 * 4) Send message out (identify message, eventually also sync.negotiations)
 * 5) Send command
 * 5a) Receive disconnect message, disconnect.
 * 5b) Reselected by target
 * 5c) Receive identify message from target.
 * 6) Send or receive data
 * 7) Receive status
 * 8) Receive message (command complete etc.)
 * 9) If status == SCSI_CHECK construct a synthetic request sense SCSI cmd.
 *    Repeat 2-8 (no disconnects please...)
 */

/*
 * Perform a request from the SCSIPI midlayer.
 */
static void
aic_scsipi_request(struct scsipi_channel *chan, scsipi_adapter_req_t req,
    void *arg)
{
        struct scsipi_xfer *xs;
        struct scsipi_periph *periph;
        struct aic_softc *sc = device_private(chan->chan_adapter->adapt_dev);
        struct aic_acb *acb;
        int s, flags;

        AIC_TRACE(("aic_request  "));

        switch (req) {
        case ADAPTER_REQ_RUN_XFER:
                xs = arg;
                periph = xs->xs_periph;

                AIC_CMDS(("[0x%x, %d]->%d ", (int)xs->cmd->opcode, xs->cmdlen,
                    periph->periph_target));

                if (!device_is_active(sc->sc_dev)) {
                        xs->error = XS_DRIVER_STUFFUP;
                        scsipi_done(xs);
                        return;
                }

                flags = xs->xs_control;
                acb = aic_get_acb(sc);
#ifdef DIAGNOSTIC
                /*
                 * This should never happen as we track the resources
                 * in the mid-layer.
                 */
                if (acb == NULL) {
                        scsipi_printaddr(periph);
                        printf("unable to allocate acb\n");
                        panic("aic_scsipi_request");
                }
#endif

                /* Initialize acb */
                acb->xs = xs;
                acb->timeout = xs->timeout;

                if (xs->xs_control & XS_CTL_RESET) {
                        acb->flags |= ACB_RESET;
                        acb->scsipi_cmd_length = 0;
                        acb->data_length = 0;
                } else {
                        memcpy(&acb->scsipi_cmd, xs->cmd, xs->cmdlen);
                        acb->scsipi_cmd_length = xs->cmdlen;
                        acb->data_addr = xs->data;
                        acb->data_length = xs->datalen;
                }
                acb->target_stat = 0;

                s = splbio();

                TAILQ_INSERT_TAIL(&sc->ready_list, acb, chain);
                if (sc->sc_state == AIC_IDLE)
                        aic_sched(sc);

                splx(s);

                if ((flags & XS_CTL_POLL) == 0)
                        return;

                /* Not allowed to use interrupts, use polling instead */
                if (aic_poll(sc, xs, acb->timeout)) {
                        aic_timeout(acb);
                        if (aic_poll(sc, xs, acb->timeout))
                                aic_timeout(acb);
                }
                return;

        case ADAPTER_REQ_GROW_RESOURCES:
                /* XXX Not supported. */
                return;

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

                ti = &sc->sc_tinfo[xm->xm_target];
                ti->flags &= ~(DO_SYNC|DO_WIDE);
                ti->period = 0;
                ti->offset = 0;

#if AIC_USE_SYNCHRONOUS
                if (xm->xm_mode & PERIPH_CAP_SYNC) {
                        ti->flags |= DO_SYNC;
                        ti->period = sc->sc_minsync;
                        ti->offset = AIC_SYNC_REQ_ACK_OFS;
                }
#endif
#if AIC_USE_WIDE
                if (xm->xm_mode & PERIPH_CAP_WIDE16) {
                        ti->flags |= DO_WIDE;
                        ti->width = AIC_MAX_WIDTH;
                }
#endif
                /*
                 * If we're not going to negotiate, send the notification
                 * now, since it won't happen later.
                 */
                if ((ti->flags & (DO_SYNC|DO_WIDE)) == 0)
                        aic_update_xfer_mode(sc, xm->xm_target);
                return;
            }
        }
}

static void
aic_update_xfer_mode(struct aic_softc *sc, int target)
{
        struct scsipi_xfer_mode xm;
        struct aic_tinfo *ti = &sc->sc_tinfo[target];

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

        if (ti->offset != 0) {
                xm.xm_mode |= PERIPH_CAP_SYNC;
                xm.xm_period = ti->period;
                xm.xm_offset = ti->offset;
        }
        switch (ti->width) {
        case 2:
                xm.xm_mode |= PERIPH_CAP_WIDE32;
                break;
        case 1:
                xm.xm_mode |= PERIPH_CAP_WIDE16;
                break;
        }

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

/*
 * Adjust transfer size in buffer structure
 */
static void
aic_minphys(struct buf *bp)
{

        AIC_TRACE(("aic_minphys  "));
        if (bp->b_bcount > (AIC_NSEG << PGSHIFT))
                bp->b_bcount = (AIC_NSEG << PGSHIFT);
        minphys(bp);
}

/*
 * Used when interrupt driven I/O isn't allowed, e.g. during boot.
 */
static int
aic_poll(struct aic_softc *sc, struct scsipi_xfer *xs, int count)
{
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;

        AIC_TRACE(("aic_poll  "));
        while (count) {
                /*
                 * If we had interrupts enabled, would we
                 * have got an interrupt?
                 */
                if ((bus_space_read_1(iot, ioh, DMASTAT) & INTSTAT) != 0)
                        aicintr(sc);
                if ((xs->xs_status & XS_STS_DONE) != 0)
                        return 0;
                delay(1000);
                count--;
        }
        return 1;
}

/*
 * LOW LEVEL SCSI UTILITIES
 */

static inline void
aic_sched_msgout(struct aic_softc *sc, u_char m)
{
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;

        if (sc->sc_msgpriq == 0)
                bus_space_write_1(iot, ioh, SCSISIG, sc->sc_phase | ATNO);
        sc->sc_msgpriq |= m;
}

/*
 * Set synchronous transfer offset and period.
 */
#if !AIC_USE_SYNCHRONOUS
/* ARGSUSED */
#endif
static inline void
aic_setsync(struct aic_softc *sc, struct aic_tinfo *ti)
{
#if AIC_USE_SYNCHRONOUS
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;

        if (ti->offset != 0)
                bus_space_write_1(iot, ioh, SCSIRATE,
                    ((ti->period * sc->sc_freq) / 250 - 2) << 4 | ti->offset);
        else
                bus_space_write_1(iot, ioh, SCSIRATE, 0);
#endif
}

/*
 * Start a selection.  This is used by aic_sched() to select an idle target,
 * and by aic_done() to immediately reselect a target to get sense information.
 */
static void
aic_select(struct aic_softc *sc, struct aic_acb *acb)
{
        struct scsipi_periph *periph = acb->xs->xs_periph;
        int target = periph->periph_target;
        struct aic_tinfo *ti = &sc->sc_tinfo[target];
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;

        bus_space_write_1(iot, ioh, SCSIID,
            sc->sc_initiator << OID_S | target);
        aic_setsync(sc, ti);
        bus_space_write_1(iot, ioh, SXFRCTL1, STIMO_256ms | ENSTIMER);

        /* Always enable reselections. */
        bus_space_write_1(iot, ioh, SIMODE0, ENSELDI | ENSELDO);
        bus_space_write_1(iot, ioh, SIMODE1, ENSCSIRST | ENSELTIMO);
        bus_space_write_1(iot, ioh, SCSISEQ, ENRESELI | ENSELO | ENAUTOATNO);

        sc->sc_state = AIC_SELECTING;
}

static int
aic_reselect(struct aic_softc *sc, int message)
{
        u_char selid, target, lun;
        struct aic_acb *acb;
        struct scsipi_periph *periph;
        struct aic_tinfo *ti;

        /*
         * The SCSI chip made a snapshot of the data bus while the reselection
         * was being negotiated.  This enables us to determine which target did
         * the reselect.
         */
        selid = sc->sc_selid & ~(1 << sc->sc_initiator);
        if (selid & (selid - 1)) {
                aprint_error_dev(sc->sc_dev,
                    "reselect with invalid selid %02x; "
                    "sending DEVICE RESET\n", selid);
                AIC_BREAK();
                goto reset;
        }

        /* Search wait queue for disconnected cmd
         * The list should be short, so I haven't bothered with
         * any more sophisticated structures than a simple
         * singly linked list.
         */
        target = ffs(selid) - 1;
        lun = message & 0x07;
        for (acb = sc->nexus_list.tqh_first; acb != NULL;
             acb = acb->chain.tqe_next) {
                periph = acb->xs->xs_periph;
                if (periph->periph_target == target &&
                    periph->periph_lun == lun)
                        break;
        }
        if (acb == NULL) {
                printf("%s: reselect from target %d lun %d with no nexus; "
                    "sending ABORT\n", device_xname(sc->sc_dev), target, lun);
                AIC_BREAK();
                goto abort;
        }

        /* Make this nexus active again. */
        TAILQ_REMOVE(&sc->nexus_list, acb, chain);
        sc->sc_state = AIC_CONNECTED;
        sc->sc_nexus = acb;
        ti = &sc->sc_tinfo[target];
        ti->lubusy |= (1 << lun);
        aic_setsync(sc, ti);

        if (acb->flags & ACB_RESET)
                aic_sched_msgout(sc, SEND_DEV_RESET);
        else if (acb->flags & ACB_ABORT)
                aic_sched_msgout(sc, SEND_ABORT);

        /* Do an implicit RESTORE POINTERS. */
        sc->sc_dp = acb->data_addr;
        sc->sc_dleft = acb->data_length;
        sc->sc_cp = (u_char *)&acb->scsipi_cmd;
        sc->sc_cleft = acb->scsipi_cmd_length;

        return (0);

reset:
        aic_sched_msgout(sc, SEND_DEV_RESET);
        return (1);

abort:
        aic_sched_msgout(sc, SEND_ABORT);
        return (1);
}

/*
 * Schedule a SCSI operation.  This has now been pulled out of the interrupt
 * handler so that we may call it from aic_scsipi_request and aic_done.  This
 * may save us an unnecessary interrupt just to get things going.  Should only
 * be called when state == AIC_IDLE and at bio pl.
 */
static void
aic_sched(struct aic_softc *sc)
{
        struct aic_acb *acb;
        struct scsipi_periph *periph;
        struct aic_tinfo *ti;
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;

        if (!device_is_active(sc->sc_dev))
                return;

        /*
         * Find first acb in ready queue that is for a target/lunit pair that
         * is not busy.
         */
        bus_space_write_1(iot, ioh, CLRSINT1,
            CLRSELTIMO | CLRBUSFREE | CLRSCSIPERR);
        for (acb = sc->ready_list.tqh_first; acb != NULL;
            acb = acb->chain.tqe_next) {
                periph = acb->xs->xs_periph;
                ti = &sc->sc_tinfo[periph->periph_target];
                if ((ti->lubusy & (1 << periph->periph_lun)) == 0) {
                        AIC_MISC(("selecting %d:%d  ",
                            periph->periph_target, periph->periph_lun));
                        TAILQ_REMOVE(&sc->ready_list, acb, chain);
                        sc->sc_nexus = acb;
                        aic_select(sc, acb);
                        return;
                } else
                        AIC_MISC(("%d:%d busy\n",
                            periph->periph_target, periph->periph_lun));
        }
        AIC_MISC(("idle  "));
        /* Nothing to start; just enable reselections and wait. */
        bus_space_write_1(iot, ioh, SIMODE0, ENSELDI);
        bus_space_write_1(iot, ioh, SIMODE1, ENSCSIRST);
        bus_space_write_1(iot, ioh, SCSISEQ, ENRESELI);
}

static void
aic_sense(struct aic_softc *sc, struct aic_acb *acb)
{
        struct scsipi_xfer *xs = acb->xs;
        struct scsipi_periph *periph = xs->xs_periph;
        struct aic_tinfo *ti = &sc->sc_tinfo[periph->periph_target];
        struct scsi_request_sense *ss = (void *)&acb->scsipi_cmd;

        AIC_MISC(("requesting sense  "));
        /* Next, setup a request sense command block */
        memset(ss, 0, sizeof(*ss));
        ss->opcode = SCSI_REQUEST_SENSE;
        ss->byte2 = periph->periph_lun << 5;
        ss->length = sizeof(struct scsi_sense_data);
        acb->scsipi_cmd_length = sizeof(*ss);
        acb->data_addr = (char *)&xs->sense.scsi_sense;
        acb->data_length = sizeof(struct scsi_sense_data);
        acb->flags |= ACB_SENSE;
        ti->senses++;
        if (acb->flags & ACB_NEXUS)
                ti->lubusy &= ~(1 << periph->periph_lun);
        if (acb == sc->sc_nexus) {
                aic_select(sc, acb);
        } else {
                aic_dequeue(sc, acb);
                TAILQ_INSERT_HEAD(&sc->ready_list, acb, chain);
                if (sc->sc_state == AIC_IDLE)
                        aic_sched(sc);
        }
}

/*
 * POST PROCESSING OF SCSI_CMD (usually current)
 */
static void
aic_done(struct aic_softc *sc, struct aic_acb *acb)
{
        struct scsipi_xfer *xs = acb->xs;
        struct scsipi_periph *periph = xs->xs_periph;
        struct aic_tinfo *ti = &sc->sc_tinfo[periph->periph_target];

        AIC_TRACE(("aic_done  "));

        /*
         * Now, if we've come here with no error code, i.e. we've kept the
         * initial XS_NOERROR, and the status code signals that we should
         * check sense, we'll need to set up a request sense cmd block and
         * push the command back into the ready queue *before* any other
         * commands for this target/lunit, else we lose the sense info.
         * We don't support chk sense conditions for the request sense cmd.
         */
        if (xs->error == XS_NOERROR) {
                if (acb->flags & ACB_ABORT) {
                        xs->error = XS_DRIVER_STUFFUP;
                } else if (acb->flags & ACB_SENSE) {
                        xs->error = XS_SENSE;
                } else if (acb->target_stat == SCSI_CHECK) {
                        /* First, save the return values */
                        xs->resid = acb->data_length;
                        xs->status = acb->target_stat;
                        aic_sense(sc, acb);
                        return;
                } else {
                        xs->resid = acb->data_length;
                }
        }

#if AIC_DEBUG
        if ((aic_debug & AIC_SHOWMISC) != 0) {
                if (xs->resid != 0)
                        printf("resid=%d ", xs->resid);
                if (xs->error == XS_SENSE)
                        printf("sense=0x%02x\n", xs->sense.scsi_sense.response_code);
                else
                        printf("error=%d\n", xs->error);
        }
#endif

        /*
         * Remove the ACB from whatever queue it happens to be on.
         */
        if (acb->flags & ACB_NEXUS)
                ti->lubusy &= ~(1 << periph->periph_lun);
        if (acb == sc->sc_nexus) {
                sc->sc_nexus = NULL;
                sc->sc_state = AIC_IDLE;
                aic_sched(sc);
        } else
                aic_dequeue(sc, acb);

        aic_free_acb(sc, acb);
        ti->cmds++;
        scsipi_done(xs);
}

static void
aic_dequeue(struct aic_softc *sc, struct aic_acb *acb)
{

        if (acb->flags & ACB_NEXUS) {
                TAILQ_REMOVE(&sc->nexus_list, acb, chain);
        } else {
                TAILQ_REMOVE(&sc->ready_list, acb, chain);
        }
}

/*
 * INTERRUPT/PROTOCOL ENGINE
 */

/*
 * Precondition:
 * The SCSI bus is already in the MSGI phase and there is a message byte
 * on the bus, along with an asserted REQ signal.
 */
static void
aic_msgin(struct aic_softc *sc)
{
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;
        u_char sstat1;
        int n;

        AIC_TRACE(("aic_msgin  "));

        if (sc->sc_prevphase == PH_MSGIN) {
                /* This is a continuation of the previous message. */
                n = sc->sc_imp - sc->sc_imess;
                goto nextbyte;
        }

        /* This is a new MESSAGE IN phase.  Clean up our state. */
        sc->sc_flags &= ~AIC_DROP_MSGIN;

nextmsg:
        n = 0;
        sc->sc_imp = &sc->sc_imess[n];

nextbyte:
        /*
         * Read a whole message, but don't ack the last byte.  If we reject the
         * message, we have to assert ATN during the message transfer phase
         * itself.
         */
        for (;;) {
                for (;;) {
                        sstat1 = bus_space_read_1(iot, ioh, SSTAT1);
                        if ((sstat1 & (REQINIT | PHASECHG | BUSFREE)) != 0)
                                break;
                        /* Wait for REQINIT.  XXX Need timeout. */
                }
                if ((sstat1 & (PHASECHG | BUSFREE)) != 0) {
                        /*
                         * Target left MESSAGE IN, probably because it
                         * a) noticed our ATN signal, or
                         * b) ran out of messages.
                         */
                        goto out;
                }

                /* If parity error, just dump everything on the floor. */
                if ((sstat1 & SCSIPERR) != 0) {
                        sc->sc_flags |= AIC_DROP_MSGIN;
                        aic_sched_msgout(sc, SEND_PARITY_ERROR);
                }

                /* Gather incoming message bytes if needed. */
                if ((sc->sc_flags & AIC_DROP_MSGIN) == 0) {
                        if (n >= AIC_MAX_MSG_LEN) {
                                (void) bus_space_read_1(iot, ioh, SCSIDAT);
                                sc->sc_flags |= AIC_DROP_MSGIN;
                                aic_sched_msgout(sc, SEND_REJECT);
                        } else {
                                *sc->sc_imp++ = bus_space_read_1(iot, ioh,
                                    SCSIDAT);
                                n++;
                                /*
                                 * This testing is suboptimal, but most
                                 * messages will be of the one byte variety, so
                                 * it should not affect performance
                                 * significantly.
                                 */
                                if (n == 1 && MSG_IS1BYTE(sc->sc_imess[0]))
                                        break;
                                if (n == 2 && MSG_IS2BYTE(sc->sc_imess[0]))
                                        break;
                                if (n >= 3 && MSG_ISEXTENDED(sc->sc_imess[0]) &&
                                    n == sc->sc_imess[1] + 2)
                                        break;
                        }
                } else
                        (void) bus_space_read_1(iot, ioh, SCSIDAT);

                /*
                 * If we reach this spot we're either:
                 * a) in the middle of a multi-byte message, or
                 * b) dropping bytes.
                 */
                bus_space_write_1(iot, ioh, SXFRCTL0, CHEN | SPIOEN);
                /* Ack the last byte read. */
                (void) bus_space_read_1(iot, ioh, SCSIDAT);
                bus_space_write_1(iot, ioh, SXFRCTL0, CHEN);
                while ((bus_space_read_1(iot, ioh, SCSISIG) & ACKI) != 0)
                        ;
        }

        AIC_MISC(("n=%d imess=0x%02x  ", n, sc->sc_imess[0]));

        /* We now have a complete message.  Parse it. */
        switch (sc->sc_state) {
                struct aic_acb *acb;
                struct aic_tinfo *ti;

        case AIC_CONNECTED:
                AIC_ASSERT(sc->sc_nexus != NULL);
                acb = sc->sc_nexus;
                ti = &sc->sc_tinfo[acb->xs->xs_periph->periph_target];

                switch (sc->sc_imess[0]) {
                case MSG_CMDCOMPLETE:
#if 0
                        /* impossible dleft is unsigned */
                        if (sc->sc_dleft < 0) {
                                periph = acb->xs->xs_periph;
                                printf("%s: %ld extra bytes from %d:%d\n",
                                    device_xname(sc->sc_dev),
                                    (long)-sc->sc_dleft,
                                    periph->periph_target, periph->periph_lun);
                                sc->sc_dleft = 0;
                        }
#endif
                        acb->xs->resid = acb->data_length = sc->sc_dleft;
                        sc->sc_state = AIC_CMDCOMPLETE;
                        break;

                case MSG_PARITY_ERROR:
                        /* Resend the last message. */
                        aic_sched_msgout(sc, sc->sc_lastmsg);
                        break;

                case MSG_MESSAGE_REJECT:
                        AIC_MISC(("message rejected %02x  ", sc->sc_lastmsg));
                        switch (sc->sc_lastmsg) {
#if AIC_USE_SYNCHRONOUS + AIC_USE_WIDE
                        case SEND_IDENTIFY:
                                ti->flags &= ~(DO_SYNC | DO_WIDE);
                                ti->period = ti->offset = 0;
                                aic_setsync(sc, ti);
                                ti->width = 0;
                                break;
#endif
#if AIC_USE_SYNCHRONOUS
                        case SEND_SDTR:
                                ti->flags &= ~DO_SYNC;
                                ti->period = ti->offset = 0;
                                aic_setsync(sc, ti);
                                aic_update_xfer_mode(sc,
                                    acb->xs->xs_periph->periph_target);
                                break;
#endif
#if AIC_USE_WIDE
                        case SEND_WDTR:
                                ti->flags &= ~DO_WIDE;
                                ti->width = 0;
                                aic_update_xfer_mode(sc,
                                    acb->xs->xs_periph->periph_target);
                                break;
#endif
                        case SEND_INIT_DET_ERR:
                                aic_sched_msgout(sc, SEND_ABORT);
                                break;
                        }
                        break;

                case MSG_NOOP:
                        break;

                case MSG_DISCONNECT:
                        ti->dconns++;
                        sc->sc_state = AIC_DISCONNECT;
                        break;

                case MSG_SAVEDATAPOINTER:
                        acb->data_addr = sc->sc_dp;
                        acb->data_length = sc->sc_dleft;
                        break;

                case MSG_RESTOREPOINTERS:
                        sc->sc_dp = acb->data_addr;
                        sc->sc_dleft = acb->data_length;
                        sc->sc_cp = (u_char *)&acb->scsipi_cmd;
                        sc->sc_cleft = acb->scsipi_cmd_length;
                        break;

                case MSG_EXTENDED:
                        switch (sc->sc_imess[2]) {
#if AIC_USE_SYNCHRONOUS
                        case MSG_EXT_SDTR:
                                if (sc->sc_imess[1] != 3)
                                        goto reject;
                                ti->period = sc->sc_imess[3];
                                ti->offset = sc->sc_imess[4];
                                ti->flags &= ~DO_SYNC;
                                if (ti->offset == 0) {
                                } else if (ti->period < sc->sc_minsync ||
                                           ti->period > sc->sc_maxsync ||
                                           ti->offset > 8) {
                                        ti->period = ti->offset = 0;
                                        aic_sched_msgout(sc, SEND_SDTR);
                                } else {
                                        aic_update_xfer_mode(sc,
                                            acb->xs->xs_periph->periph_target);
                                }
                                aic_setsync(sc, ti);
                                break;
#endif

#if AIC_USE_WIDE
                        case MSG_EXT_WDTR:
                                if (sc->sc_imess[1] != 2)
                                        goto reject;
                                ti->width = sc->sc_imess[3];
                                ti->flags &= ~DO_WIDE;
                                if (ti->width == 0) {
                                } else if (ti->width > AIC_MAX_WIDTH) {
                                        ti->width = 0;
                                        aic_sched_msgout(sc, SEND_WDTR);
                                } else {
                                        aic_update_xfer_mode(sc,
                                            acb->xs->xs_periph->periph_target);
                                }
                                break;
#endif

                        default:
                                printf("%s: unrecognized MESSAGE EXTENDED; "
                                    "sending REJECT\n",
                                    device_xname(sc->sc_dev));
                                AIC_BREAK();
                                goto reject;
                        }
                        break;

                default:
                        printf("%s: unrecognized MESSAGE; sending REJECT\n",
                            device_xname(sc->sc_dev));
                        AIC_BREAK();
                reject:
                        aic_sched_msgout(sc, SEND_REJECT);
                        break;
                }
                break;

        case AIC_RESELECTED:
                if (!MSG_ISIDENTIFY(sc->sc_imess[0])) {
                        printf("%s: reselect without IDENTIFY; "
                            "sending DEVICE RESET\n", device_xname(sc->sc_dev));
                        AIC_BREAK();
                        goto reset;
                }

                (void) aic_reselect(sc, sc->sc_imess[0]);
                break;

        default:
                aprint_error_dev(sc->sc_dev,
                    "unexpected MESSAGE IN; sending DEVICE RESET\n");
                AIC_BREAK();
        reset:
                aic_sched_msgout(sc, SEND_DEV_RESET);
                break;

#ifdef notdef
        abort:
                aic_sched_msgout(sc, SEND_ABORT);
                break;
#endif
        }

        bus_space_write_1(iot, ioh, SXFRCTL0, CHEN | SPIOEN);
        /* Ack the last message byte. */
        (void) bus_space_read_1(iot, ioh, SCSIDAT);
        bus_space_write_1(iot, ioh, SXFRCTL0, CHEN);
        while ((bus_space_read_1(iot, ioh, SCSISIG) & ACKI) != 0)
                ;

        /* Go get the next message, if any. */
        goto nextmsg;

out:
        AIC_MISC(("n=%d imess=0x%02x  ", n, sc->sc_imess[0]));
}

/*
 * Send the highest priority, scheduled message.
 */
static void
aic_msgout(struct aic_softc *sc)
{
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;
#if AIC_USE_SYNCHRONOUS
        struct aic_tinfo *ti;
#endif
        u_char sstat1;
        int n;

        AIC_TRACE(("aic_msgout  "));

        /* Reset the FIFO. */
        bus_space_write_1(iot, ioh, DMACNTRL0, RSTFIFO);
        /* Enable REQ/ACK protocol. */
        bus_space_write_1(iot, ioh, SXFRCTL0, CHEN | SPIOEN);

        if (sc->sc_prevphase == PH_MSGOUT) {
                if (sc->sc_omp == sc->sc_omess) {
                        /*
                         * This is a retransmission.
                         *
                         * We get here if the target stayed in MESSAGE OUT
                         * phase.  Section 5.1.9.2 of the SCSI 2 spec indicates
                         * that all of the previously transmitted messages must
                         * be sent again, in the same order.  Therefore, we
                         * requeue all the previously transmitted messages, and
                         * start again from the top.  Our simple priority
                         * scheme keeps the messages in the right order.
                         */
                        AIC_MISC(("retransmitting  "));
                        sc->sc_msgpriq |= sc->sc_msgoutq;
                        /*
                         * Set ATN.  If we're just sending a trivial 1-byte
                         * message, we'll clear ATN later on anyway.
                         */
                        bus_space_write_1(iot, ioh, SCSISIG, PH_MSGOUT | ATNO);
                } else {
                        /* This is a continuation of the previous message. */
                        n = sc->sc_omp - sc->sc_omess;
                        goto nextbyte;
                }
        }

        /* No messages transmitted so far. */
        sc->sc_msgoutq = 0;
        sc->sc_lastmsg = 0;

nextmsg:
        /* Pick up highest priority message. */
        sc->sc_currmsg = sc->sc_msgpriq & -sc->sc_msgpriq;
        sc->sc_msgpriq &= ~sc->sc_currmsg;
        sc->sc_msgoutq |= sc->sc_currmsg;

        /* Build the outgoing message data. */
        switch (sc->sc_currmsg) {
        case SEND_IDENTIFY:
                AIC_ASSERT(sc->sc_nexus != NULL);
                sc->sc_omess[0] =
                    MSG_IDENTIFY(sc->sc_nexus->xs->xs_periph->periph_lun, 1);
                n = 1;
                break;

#if AIC_USE_SYNCHRONOUS
        case SEND_SDTR:
                AIC_ASSERT(sc->sc_nexus != NULL);
                ti = &sc->sc_tinfo[sc->sc_nexus->xs->xs_periph->periph_target];
                sc->sc_omess[4] = MSG_EXTENDED;
                sc->sc_omess[3] = 3;
                sc->sc_omess[2] = MSG_EXT_SDTR;
                sc->sc_omess[1] = ti->period >> 2;
                sc->sc_omess[0] = ti->offset;
                n = 5;
                break;
#endif

#if AIC_USE_WIDE
        case SEND_WDTR:
                AIC_ASSERT(sc->sc_nexus != NULL);
                ti = &sc->sc_tinfo[sc->sc_nexus->xs->xs_periph->periph_target];
                sc->sc_omess[3] = MSG_EXTENDED;
                sc->sc_omess[2] = 2;
                sc->sc_omess[1] = MSG_EXT_WDTR;
                sc->sc_omess[0] = ti->width;
                n = 4;
                break;
#endif

        case SEND_DEV_RESET:
                sc->sc_flags |= AIC_ABORTING;
                sc->sc_omess[0] = MSG_BUS_DEV_RESET;
                n = 1;
                break;

        case SEND_REJECT:
                sc->sc_omess[0] = MSG_MESSAGE_REJECT;
                n = 1;
                break;

        case SEND_PARITY_ERROR:
                sc->sc_omess[0] = MSG_PARITY_ERROR;
                n = 1;
                break;

        case SEND_INIT_DET_ERR:
                sc->sc_omess[0] = MSG_INITIATOR_DET_ERR;
                n = 1;
                break;

        case SEND_ABORT:
                sc->sc_flags |= AIC_ABORTING;
                sc->sc_omess[0] = MSG_ABORT;
                n = 1;
                break;

        default:
                aprint_error_dev(sc->sc_dev,
                    "unexpected MESSAGE OUT; sending NOOP\n");
                AIC_BREAK();
                sc->sc_omess[0] = MSG_NOOP;
                n = 1;
                break;
        }
        sc->sc_omp = &sc->sc_omess[n];

nextbyte:
        /* Send message bytes. */
        for (;;) {
                for (;;) {
                        sstat1 = bus_space_read_1(iot, ioh, SSTAT1);
                        if ((sstat1 & (REQINIT | PHASECHG | BUSFREE)) != 0)
                                break;
                        /* Wait for REQINIT.  XXX Need timeout. */
                }
                if ((sstat1 & (PHASECHG | BUSFREE)) != 0) {
                        /*
                         * Target left MESSAGE OUT, possibly to reject
                         * our message.
                         *
                         * If this is the last message being sent, then we
                         * deassert ATN, since either the target is going to
                         * ignore this message, or it's going to ask for a
                         * retransmission via MESSAGE PARITY ERROR (in which
                         * case we reassert ATN anyway).
                         */
                        if (sc->sc_msgpriq == 0)
                                bus_space_write_1(iot, ioh, CLRSINT1, CLRATNO);
                        goto out;
                }

                /* Clear ATN before last byte if this is the last message. */
                if (n == 1 && sc->sc_msgpriq == 0)
                        bus_space_write_1(iot, ioh, CLRSINT1, CLRATNO);
                /* Send message byte. */
                bus_space_write_1(iot, ioh, SCSIDAT, *--sc->sc_omp);
                --n;
                /* Keep track of the last message we've sent any bytes of. */
                sc->sc_lastmsg = sc->sc_currmsg;
                /* Wait for ACK to be negated.  XXX Need timeout. */
                while ((bus_space_read_1(iot, ioh, SCSISIG) & ACKI) != 0)
                        ;

                if (n == 0)
                        break;
        }

        /* We get here only if the entire message has been transmitted. */
        if (sc->sc_msgpriq != 0) {
                /* There are more outgoing messages. */
                goto nextmsg;
        }

        /*
         * The last message has been transmitted.  We need to remember the last
         * message transmitted (in case the target switches to MESSAGE IN phase
         * and sends a MESSAGE REJECT), and the list of messages transmitted
         * this time around (in case the target stays in MESSAGE OUT phase to
         * request a retransmit).
         */

out:
        /* Disable REQ/ACK protocol. */
        bus_space_write_1(iot, ioh, SXFRCTL0, CHEN);
}

/* aic_dataout_pio: perform a data transfer using the FIFO datapath in the
 * aic6360
 * Precondition: The SCSI bus should be in the DOUT phase, with REQ asserted
 * and ACK deasserted (i.e. waiting for a data byte)
 * This new revision has been optimized (I tried) to make the common case fast,
 * and the rarer cases (as a result) somewhat more comlex
 */
static int
aic_dataout_pio(struct aic_softc *sc, u_char *p, int n)
{
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;
        u_char dmastat = 0;
        int out = 0;
#define DOUTAMOUNT 128          /* Full FIFO */

        AIC_MISC(("%02x%02x  ", bus_space_read_1(iot, ioh, FIFOSTAT),
            bus_space_read_1(iot, ioh, SSTAT2)));

        /* Clear host FIFO and counter. */
        bus_space_write_1(iot, ioh, DMACNTRL0, RSTFIFO | WRITE);
        /* Enable FIFOs. */
        bus_space_write_1(iot, ioh, DMACNTRL0, ENDMA | DWORDPIO | WRITE);
        bus_space_write_1(iot, ioh, SXFRCTL0, SCSIEN | DMAEN | CHEN);

        /* Turn off ENREQINIT for now. */
        bus_space_write_1(iot, ioh, SIMODE1,
            ENSCSIRST | ENSCSIPERR | ENBUSFREE | ENPHASECHG);

        /* I have tried to make the main loop as tight as possible.  This
         * means that some of the code following the loop is a bit more
         * complex than otherwise.
         */
        while (n > 0) {
                for (;;) {
                        dmastat = bus_space_read_1(iot, ioh, DMASTAT);
                        if ((dmastat & (DFIFOEMP | INTSTAT)) != 0)
                                break;
                }

                if ((dmastat & INTSTAT) != 0)
                        goto phasechange;

                if (n >= DOUTAMOUNT) {
                        n -= DOUTAMOUNT;
                        out += DOUTAMOUNT;

#if AIC_USE_DWORDS
                        bus_space_write_multi_4(iot, ioh, DMADATALONG,
                            (u_int32_t *) p, DOUTAMOUNT >> 2);
#else
                        bus_space_write_multi_2(iot, ioh, DMADATA,
                            (u_int16_t *) p, DOUTAMOUNT >> 1);
#endif

                        p += DOUTAMOUNT;
                } else {
                        int xfer;

                        xfer = n;
                        AIC_MISC(("%d> ", xfer));

                        n -= xfer;
                        out += xfer;

#if AIC_USE_DWORDS
                        if (xfer >= 12) {
                                bus_space_write_multi_4(iot, ioh, DMADATALONG,
                                    (u_int32_t *) p, xfer >> 2);
                                p += xfer & ~3;
                                xfer &= 3;
                        }
#else
                        if (xfer >= 8) {
                                bus_space_write_multi_2(iot, ioh, DMADATA,
                                    (u_int16_t *) p, xfer >> 1);
                                p += xfer & ~1;
                                xfer &= 1;
                        }
#endif

                        if (xfer > 0) {
                                bus_space_write_1(iot, ioh, DMACNTRL0,
                                    ENDMA | B8MODE | WRITE);
                                bus_space_write_multi_1(iot, ioh, DMADATA,
                                    p, xfer);
                                p += xfer;
                                bus_space_write_1(iot, ioh, DMACNTRL0,
                                    ENDMA | DWORDPIO | WRITE);
                        }
                }
        }

        if (out == 0) {
                bus_space_write_1(iot, ioh, SXFRCTL1, BITBUCKET);
                for (;;) {
                        if ((bus_space_read_1(iot, ioh, DMASTAT) & INTSTAT)
                            != 0)
                                break;
                }
                bus_space_write_1(iot, ioh, SXFRCTL1, 0);
                AIC_MISC(("extra data  "));
        } else {
                /* See the bytes off chip */
                for (;;) {
                        dmastat = bus_space_read_1(iot, ioh, DMASTAT);
                        if ((dmastat & INTSTAT) != 0)
                                goto phasechange;
                        if ((dmastat & DFIFOEMP) != 0 &&
                            (bus_space_read_1(iot, ioh, SSTAT2) & SEMPTY) != 0)
                                break;
                }
        }

phasechange:
        if ((dmastat & INTSTAT) != 0) {
                /* Some sort of phase change. */
                int amount;

                /* Stop transfers, do some accounting */
                amount = bus_space_read_1(iot, ioh, FIFOSTAT)
                    + (bus_space_read_1(iot, ioh, SSTAT2) & 15);
                if (amount > 0) {
                        out -= amount;
                        bus_space_write_1(iot, ioh, DMACNTRL0,
                            RSTFIFO | WRITE);
                        bus_space_write_1(iot, ioh, SXFRCTL0, CHEN | CLRCH);
                        AIC_MISC(("+%d ", amount));
                }
        }

        /* Turn on ENREQINIT again. */
        bus_space_write_1(iot, ioh, SIMODE1,
            ENSCSIRST | ENSCSIPERR | ENBUSFREE | ENREQINIT | ENPHASECHG);

        /* Stop the FIFO data path. */
        bus_space_write_1(iot, ioh, SXFRCTL0, CHEN);
        bus_space_write_1(iot, ioh, DMACNTRL0, 0);

        return out;
}

/* aic_datain_pio: perform data transfers using the FIFO datapath in the
 * aic6360
 * Precondition: The SCSI bus should be in the DIN phase, with REQ asserted
 * and ACK deasserted (i.e. at least one byte is ready).
 * For now, uses a pretty dumb algorithm, hangs around until all data has been
 * transferred.  This, is OK for fast targets, but not so smart for slow
 * targets which don't disconnect or for huge transfers.
 */
static int
aic_datain_pio(struct aic_softc *sc, u_char *p, int n)
{
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;
        u_char dmastat;
        int in = 0;
#define DINAMOUNT 128           /* Full FIFO */

        AIC_MISC(("%02x%02x  ", bus_space_read_1(iot, ioh, FIFOSTAT),
            bus_space_read_1(iot, ioh, SSTAT2)));

        /* Clear host FIFO and counter. */
        bus_space_write_1(iot, ioh, DMACNTRL0, RSTFIFO);
        /* Enable FIFOs. */
        bus_space_write_1(iot, ioh, DMACNTRL0, ENDMA | DWORDPIO);
        bus_space_write_1(iot, ioh, SXFRCTL0, SCSIEN | DMAEN | CHEN);

        /* Turn off ENREQINIT for now. */
        bus_space_write_1(iot, ioh, SIMODE1,
            ENSCSIRST | ENSCSIPERR | ENBUSFREE | ENPHASECHG);

        /* We leave this loop if one or more of the following is true:
         * a) phase != PH_DATAIN && FIFOs are empty
         * b) SCSIRSTI is set (a reset has occurred) or busfree is detected.
         */
        while (n > 0) {
                /* Wait for fifo half full or phase mismatch */
                for (;;) {
                        dmastat = bus_space_read_1(iot, ioh, DMASTAT);
                        if ((dmastat & (DFIFOFULL | INTSTAT)) != 0)
                                break;
                }

                if ((dmastat & DFIFOFULL) != 0) {
                        n -= DINAMOUNT;
                        in += DINAMOUNT;

#if AIC_USE_DWORDS
                        bus_space_read_multi_4(iot, ioh, DMADATALONG,
                            (u_int32_t *) p, DINAMOUNT >> 2);
#else
                        bus_space_read_multi_2(iot, ioh, DMADATA,
                            (u_int16_t *) p, DINAMOUNT >> 1);
#endif

                        p += DINAMOUNT;
                } else {
                        int xfer;

                        xfer = min(bus_space_read_1(iot, ioh, FIFOSTAT), n);
                        AIC_MISC((">%d ", xfer));

                        n -= xfer;
                        in += xfer;

#if AIC_USE_DWORDS
                        if (xfer >= 12) {
                                bus_space_read_multi_4(iot, ioh, DMADATALONG,
                                    (u_int32_t *) p, xfer >> 2);
                                p += xfer & ~3;
                                xfer &= 3;
                        }
#else
                        if (xfer >= 8) {
                                bus_space_read_multi_2(iot, ioh, DMADATA,
                                    (u_int16_t *) p, xfer >> 1);
                                p += xfer & ~1;
                                xfer &= 1;
                        }
#endif

                        if (xfer > 0) {
                                bus_space_write_1(iot, ioh, DMACNTRL0,
                                    ENDMA | B8MODE);
                                bus_space_read_multi_1(iot, ioh, DMADATA,
                                    p, xfer);
                                p += xfer;
                                bus_space_write_1(iot, ioh, DMACNTRL0,
                                    ENDMA | DWORDPIO);
                        }
                }

                if ((dmastat & INTSTAT) != 0)
                        goto phasechange;
        }

        /* Some SCSI-devices are rude enough to transfer more data than what
         * was requested, e.g. 2048 bytes from a CD-ROM instead of the
         * requested 512.  Test for progress, i.e. real transfers.  If no real
         * transfers have been performed (n is probably already zero) and the
         * FIFO is not empty, waste some bytes....
         */
        if (in == 0) {
                bus_space_write_1(iot, ioh, SXFRCTL1, BITBUCKET);
                for (;;) {
                        if ((bus_space_read_1(iot, ioh, DMASTAT) & INTSTAT)
                            != 0)
                                break;
                }
                bus_space_write_1(iot, ioh, SXFRCTL1, 0);
                AIC_MISC(("extra data  "));
        }

phasechange:
        /* Turn on ENREQINIT again. */
        bus_space_write_1(iot, ioh, SIMODE1,
            ENSCSIRST | ENSCSIPERR | ENBUSFREE | ENREQINIT | ENPHASECHG);

        /* Stop the FIFO data path. */
        bus_space_write_1(iot, ioh, SXFRCTL0, CHEN);
        bus_space_write_1(iot, ioh, DMACNTRL0, 0);

        return in;
}

/*
 * This is the workhorse routine of the driver.
 * Deficiencies (for now):
 * 1) always uses programmed I/O
 */
int
aicintr(void *arg)
{
        struct aic_softc *sc = arg;
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;
        u_char sstat0, sstat1;
        struct aic_acb *acb;
        struct scsipi_periph *periph;
        struct aic_tinfo *ti;
        int n;

        if (!device_is_active(sc->sc_dev))
                return (0);

        /*
         * Clear INTEN.  We enable it again before returning.  This makes the
         * interrupt esssentially level-triggered.
         */
        bus_space_write_1(iot, ioh, DMACNTRL0, 0);

        AIC_TRACE(("aicintr  "));

loop:
        /*
         * First check for abnormal conditions, such as reset.
         */
        sstat1 = bus_space_read_1(iot, ioh, SSTAT1);
        AIC_MISC(("sstat1:0x%02x ", sstat1));

        if ((sstat1 & SCSIRSTI) != 0) {
                printf("%s: SCSI bus reset\n", device_xname(sc->sc_dev));
                goto reset;
        }

        /*
         * Check for less serious errors.
         */
        if ((sstat1 & SCSIPERR) != 0) {
                printf("%s: SCSI bus parity error\n", device_xname(sc->sc_dev));
                bus_space_write_1(iot, ioh, CLRSINT1, CLRSCSIPERR);
                if (sc->sc_prevphase == PH_MSGIN) {
                        sc->sc_flags |= AIC_DROP_MSGIN;
                        aic_sched_msgout(sc, SEND_PARITY_ERROR);
                } else
                        aic_sched_msgout(sc, SEND_INIT_DET_ERR);
        }

        /*
         * If we're not already busy doing something test for the following
         * conditions:
         * 1) We have been reselected by something
         * 2) We have selected something successfully
         * 3) Our selection process has timed out
         * 4) This is really a bus free interrupt just to get a new command
         *    going?
         * 5) Spurious interrupt?
         */
        switch (sc->sc_state) {
        case AIC_IDLE:
        case AIC_SELECTING:
                sstat0 = bus_space_read_1(iot, ioh, SSTAT0);
                AIC_MISC(("sstat0:0x%02x ", sstat0));

                if ((sstat0 & TARGET) != 0) {
                        /*
                         * We don't currently support target mode.
                         */
                        printf("%s: target mode selected; going to BUS FREE\n",
                            device_xname(sc->sc_dev));
                        bus_space_write_1(iot, ioh, SCSISIG, 0);

                        goto sched;
                } else if ((sstat0 & SELDI) != 0) {
                        AIC_MISC(("reselected  "));

                        /*
                         * If we're trying to select a target ourselves,
                         * push our command back into the ready list.
                         */
                        if (sc->sc_state == AIC_SELECTING) {
                                AIC_MISC(("backoff selector  "));
                                AIC_ASSERT(sc->sc_nexus != NULL);
                                acb = sc->sc_nexus;
                                sc->sc_nexus = NULL;
                                TAILQ_INSERT_HEAD(&sc->ready_list, acb, chain);
                        }

                        /* Save reselection ID. */
                        sc->sc_selid = bus_space_read_1(iot, ioh, SELID);

                        sc->sc_state = AIC_RESELECTED;
                } else if ((sstat0 & SELDO) != 0) {
                        AIC_MISC(("selected  "));

                        /* We have selected a target. Things to do:
                         * a) Determine what message(s) to send.
                         * b) Verify that we're still selecting the target.
                         * c) Mark device as busy.
                         */
                        if (sc->sc_state != AIC_SELECTING) {
                                printf("%s: selection out while idle; "
                                    "resetting\n", device_xname(sc->sc_dev));
                                AIC_BREAK();
                                goto reset;
                        }
                        AIC_ASSERT(sc->sc_nexus != NULL);
                        acb = sc->sc_nexus;
                        periph = acb->xs->xs_periph;
                        ti = &sc->sc_tinfo[periph->periph_target];

                        sc->sc_msgpriq = SEND_IDENTIFY;
                        if (acb->flags & ACB_RESET)
                                sc->sc_msgpriq |= SEND_DEV_RESET;
                        else if (acb->flags & ACB_ABORT)
                                sc->sc_msgpriq |= SEND_ABORT;
                        else {
#if AIC_USE_SYNCHRONOUS
                                if ((ti->flags & DO_SYNC) != 0)
                                        sc->sc_msgpriq |= SEND_SDTR;
#endif
#if AIC_USE_WIDE
                                if ((ti->flags & DO_WIDE) != 0)
                                        sc->sc_msgpriq |= SEND_WDTR;
#endif
                        }

                        acb->flags |= ACB_NEXUS;
                        ti->lubusy |= (1 << periph->periph_lun);

                        /* Do an implicit RESTORE POINTERS. */
                        sc->sc_dp = acb->data_addr;
                        sc->sc_dleft = acb->data_length;
                        sc->sc_cp = (u_char *)&acb->scsipi_cmd;
                        sc->sc_cleft = acb->scsipi_cmd_length;

                        /* On our first connection, schedule a timeout. */
                        if ((acb->xs->xs_control & XS_CTL_POLL) == 0)
                                callout_reset(&acb->xs->xs_callout,
                                    mstohz(acb->timeout), aic_timeout, acb);

                        sc->sc_state = AIC_CONNECTED;
                } else if ((sstat1 & SELTO) != 0) {
                        AIC_MISC(("selection timeout  "));

                        if (sc->sc_state != AIC_SELECTING) {
                                printf("%s: selection timeout while idle; "
                                    "resetting\n", device_xname(sc->sc_dev));
                                AIC_BREAK();
                                goto reset;
                        }
                        AIC_ASSERT(sc->sc_nexus != NULL);
                        acb = sc->sc_nexus;

                        bus_space_write_1(iot, ioh, SXFRCTL1, 0);
                        bus_space_write_1(iot, ioh, SCSISEQ, ENRESELI);
                        bus_space_write_1(iot, ioh, CLRSINT1, CLRSELTIMO);
                        delay(250);

                        acb->xs->error = XS_SELTIMEOUT;
                        goto finish;
                } else {
                        if (sc->sc_state != AIC_IDLE) {
                                printf("%s: BUS FREE while not idle; "
                                    "state=%d\n",
                                    device_xname(sc->sc_dev), sc->sc_state);
                                AIC_BREAK();
                                goto out;
                        }

                        goto sched;
                }

                /*
                 * Turn off selection stuff, and prepare to catch bus free
                 * interrupts, parity errors, and phase changes.
                 */
                bus_space_write_1(iot, ioh, SXFRCTL0, CHEN | CLRSTCNT | CLRCH);
                bus_space_write_1(iot, ioh, SXFRCTL1, 0);
                bus_space_write_1(iot, ioh, SCSISEQ, ENAUTOATNP);
                bus_space_write_1(iot, ioh, CLRSINT0, CLRSELDI | CLRSELDO);
                bus_space_write_1(iot, ioh, CLRSINT1,
                    CLRBUSFREE | CLRPHASECHG);
                bus_space_write_1(iot, ioh, SIMODE0, 0);
                bus_space_write_1(iot, ioh, SIMODE1,
                    ENSCSIRST | ENSCSIPERR | ENBUSFREE | ENREQINIT |
                    ENPHASECHG);

                sc->sc_flags = 0;
                sc->sc_prevphase = PH_INVALID;
                goto dophase;
        }

        if ((sstat1 & BUSFREE) != 0) {
                /* We've gone to BUS FREE phase. */
                bus_space_write_1(iot, ioh, CLRSINT1,
                    CLRBUSFREE | CLRPHASECHG);

                switch (sc->sc_state) {
                case AIC_RESELECTED:
                        goto sched;

                case AIC_CONNECTED:
                        AIC_ASSERT(sc->sc_nexus != NULL);
                        acb = sc->sc_nexus;

#if AIC_USE_SYNCHRONOUS + AIC_USE_WIDE
                        if (sc->sc_prevphase == PH_MSGOUT) {
                                /*
                                 * If the target went to BUS FREE phase during
                                 * or immediately after sending a SDTR or WDTR
                                 * message, disable negotiation.
                                 */
                                periph = acb->xs->xs_periph;
                                ti = &sc->sc_tinfo[periph->periph_target];
                                switch (sc->sc_lastmsg) {
#if AIC_USE_SYNCHRONOUS
                                case SEND_SDTR:
                                        ti->flags &= ~DO_SYNC;
                                        ti->period = ti->offset = 0;
                                        break;
#endif
#if AIC_USE_WIDE
                                case SEND_WDTR:
                                        ti->flags &= ~DO_WIDE;
                                        ti->width = 0;
                                        break;
#endif
                                }
                        }
#endif

                        if ((sc->sc_flags & AIC_ABORTING) == 0) {
                                /*
                                 * Section 5.1.1 of the SCSI 2 spec suggests
                                 * issuing a REQUEST SENSE following an
                                 * unexpected disconnect.  Some devices go into
                                 * a contingent allegiance condition when
                                 * disconnecting, and this is necessary to
                                 * clean up their state.
                                 */
                                aprint_error_dev(sc->sc_dev,
                                    "unexpected disconnect; "
                                    "sending REQUEST SENSE\n");
                                AIC_BREAK();
                                aic_sense(sc, acb);
                                goto out;
                        }

                        acb->xs->error = XS_DRIVER_STUFFUP;
                        goto finish;

                case AIC_DISCONNECT:
                        AIC_ASSERT(sc->sc_nexus != NULL);
                        acb = sc->sc_nexus;
#if 1 /* XXXX */
                        acb->data_addr = sc->sc_dp;
                        acb->data_length = sc->sc_dleft;
#endif
                        TAILQ_INSERT_HEAD(&sc->nexus_list, acb, chain);
                        sc->sc_nexus = NULL;
                        goto sched;

                case AIC_CMDCOMPLETE:
                        AIC_ASSERT(sc->sc_nexus != NULL);
                        acb = sc->sc_nexus;
                        goto finish;
                }
        }

        bus_space_write_1(iot, ioh, CLRSINT1, CLRPHASECHG);

dophase:
        if ((sstat1 & REQINIT) == 0) {
                /* Wait for REQINIT. */
                goto out;
        }

        sc->sc_phase = bus_space_read_1(iot, ioh, SCSISIG) & PH_MASK;
        bus_space_write_1(iot, ioh, SCSISIG, sc->sc_phase);

        switch (sc->sc_phase) {
        case PH_MSGOUT:
                if (sc->sc_state != AIC_CONNECTED &&
                    sc->sc_state != AIC_RESELECTED)
                        break;
                aic_msgout(sc);
                sc->sc_prevphase = PH_MSGOUT;
                goto loop;

        case PH_MSGIN:
                if (sc->sc_state != AIC_CONNECTED &&
                    sc->sc_state != AIC_RESELECTED)
                        break;
                aic_msgin(sc);
                sc->sc_prevphase = PH_MSGIN;
                goto loop;

        case PH_CMD:
                if (sc->sc_state != AIC_CONNECTED)
                        break;
#if AIC_DEBUG
                if ((aic_debug & AIC_SHOWMISC) != 0) {
                        AIC_ASSERT(sc->sc_nexus != NULL);
                        acb = sc->sc_nexus;
                        printf("cmd=0x%02x+%d ",
                            acb->scsipi_cmd.opcode, acb->scsipi_cmd_length-1);
                }
#endif
                n = aic_dataout_pio(sc, sc->sc_cp, sc->sc_cleft);
                sc->sc_cp += n;
                sc->sc_cleft -= n;
                sc->sc_prevphase = PH_CMD;
                goto loop;

        case PH_DATAOUT:
                if (sc->sc_state != AIC_CONNECTED)
                        break;
                AIC_MISC(("dataout %ld ", (long)sc->sc_dleft));
                n = aic_dataout_pio(sc, sc->sc_dp, sc->sc_dleft);
                sc->sc_dp += n;
                sc->sc_dleft -= n;
                sc->sc_prevphase = PH_DATAOUT;
                goto loop;

        case PH_DATAIN:
                if (sc->sc_state != AIC_CONNECTED)
                        break;
                AIC_MISC(("datain %ld ", (long)sc->sc_dleft));
                n = aic_datain_pio(sc, sc->sc_dp, sc->sc_dleft);
                sc->sc_dp += n;
                sc->sc_dleft -= n;
                sc->sc_prevphase = PH_DATAIN;
                goto loop;

        case PH_STAT:
                if (sc->sc_state != AIC_CONNECTED)
                        break;
                AIC_ASSERT(sc->sc_nexus != NULL);
                acb = sc->sc_nexus;
                bus_space_write_1(iot, ioh, SXFRCTL0, CHEN | SPIOEN);
                acb->target_stat = bus_space_read_1(iot, ioh, SCSIDAT);
                bus_space_write_1(iot, ioh, SXFRCTL0, CHEN);
                AIC_MISC(("target_stat=0x%02x  ", acb->target_stat));
                sc->sc_prevphase = PH_STAT;
                goto loop;
        }

        aprint_error_dev(sc->sc_dev, "unexpected bus phase; resetting\n");
        AIC_BREAK();
reset:
        aic_init(sc, 1);
        return 1;

finish:
        callout_stop(&acb->xs->xs_callout);
        aic_done(sc, acb);
        goto out;

sched:
        sc->sc_state = AIC_IDLE;
        aic_sched(sc);
        goto out;

out:
        bus_space_write_1(iot, ioh, DMACNTRL0, INTEN);
        return 1;
}

static void
aic_abort(struct aic_softc *sc, struct aic_acb *acb)
{

        /* 2 secs for the abort */
        acb->timeout = AIC_ABORT_TIMEOUT;
        acb->flags |= ACB_ABORT;

        if (acb == sc->sc_nexus) {
                /*
                 * If we're still selecting, the message will be scheduled
                 * after selection is complete.
                 */
                if (sc->sc_state == AIC_CONNECTED)
                        aic_sched_msgout(sc, SEND_ABORT);
        } else {
                aic_dequeue(sc, acb);
                TAILQ_INSERT_HEAD(&sc->ready_list, acb, chain);
                if (sc->sc_state == AIC_IDLE)
                        aic_sched(sc);
        }
}

static void
aic_timeout(void *arg)
{
        struct aic_acb *acb = arg;
        struct scsipi_xfer *xs = acb->xs;
        struct scsipi_periph *periph = xs->xs_periph;
        struct aic_softc *sc =
            device_private(periph->periph_channel->chan_adapter->adapt_dev);
        int s;

        scsipi_printaddr(periph);
        printf("timed out");

        s = splbio();

        if (acb->flags & ACB_ABORT) {
                /* abort timed out */
                printf(" AGAIN\n");
                /* XXX Must reset! */
        } else {
                /* abort the operation that has timed out */
                printf("\n");
                acb->xs->error = XS_TIMEOUT;
                aic_abort(sc, acb);
        }

        splx(s);
}

#ifdef AIC_DEBUG
/*
 * The following functions are mostly used for debugging purposes, either
 * directly called from the driver or from the kernel debugger.
 */

static void
aic_show_scsi_cmd(struct aic_acb *acb)
{
        u_char  *b = (u_char *)&acb->scsipi_cmd;
        struct scsipi_periph *periph = acb->xs->xs_periph;
        int i;

        scsipi_printaddr(periph);
        if ((acb->xs->xs_control & XS_CTL_RESET) == 0) {
                for (i = 0; i < acb->scsipi_cmd_length; i++) {
                        if (i)
                                printf(",");
                        printf("%x", b[i]);
                }
                printf("\n");
        } else
                printf("RESET\n");
}

static void
aic_print_acb(struct aic_acb *acb)
{

        printf("acb@%p xs=%p flags=%x", acb, acb->xs, acb->flags);
        printf(" dp=%p dleft=%d target_stat=%x\n",
               acb->data_addr, acb->data_length, acb->target_stat);
        aic_show_scsi_cmd(acb);
}

void
aic_print_active_acb(void)
{
        extern struct cfdriver aic_cd;
        struct aic_acb *acb;
        struct aic_softc *sc = device_lookup_private(&aic_cd, 0);

        printf("ready list:\n");
        for (acb = sc->ready_list.tqh_first; acb != NULL;
            acb = acb->chain.tqe_next)
                aic_print_acb(acb);
        printf("nexus:\n");
        if (sc->sc_nexus != NULL)
                aic_print_acb(sc->sc_nexus);
        printf("nexus list:\n");
        for (acb = sc->nexus_list.tqh_first; acb != NULL;
            acb = acb->chain.tqe_next)
                aic_print_acb(acb);
}

void
aic_dump6360(struct aic_softc *sc)
{
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;

        printf("aic6360: SCSISEQ=%x SXFRCTL0=%x SXFRCTL1=%x SCSISIG=%x\n",
            bus_space_read_1(iot, ioh, SCSISEQ),
            bus_space_read_1(iot, ioh, SXFRCTL0),
            bus_space_read_1(iot, ioh, SXFRCTL1),
            bus_space_read_1(iot, ioh, SCSISIG));
        printf("         SSTAT0=%x SSTAT1=%x SSTAT2=%x SSTAT3=%x SSTAT4=%x\n",
            bus_space_read_1(iot, ioh, SSTAT0),
            bus_space_read_1(iot, ioh, SSTAT1),
            bus_space_read_1(iot, ioh, SSTAT2),
            bus_space_read_1(iot, ioh, SSTAT3),
            bus_space_read_1(iot, ioh, SSTAT4));
        printf("         SIMODE0=%x SIMODE1=%x DMACNTRL0=%x DMACNTRL1=%x "
            "DMASTAT=%x\n",
            bus_space_read_1(iot, ioh, SIMODE0),
            bus_space_read_1(iot, ioh, SIMODE1),
            bus_space_read_1(iot, ioh, DMACNTRL0),
            bus_space_read_1(iot, ioh, DMACNTRL1),
            bus_space_read_1(iot, ioh, DMASTAT));
        printf("         FIFOSTAT=%d SCSIBUS=0x%x\n",
            bus_space_read_1(iot, ioh, FIFOSTAT),
            bus_space_read_1(iot, ioh, SCSIBUS));
}

void
aic_dump_driver(struct aic_softc *sc)
{
        struct aic_tinfo *ti;
        int i;

        printf("nexus=%p prevphase=%x\n", sc->sc_nexus, sc->sc_prevphase);
        printf("state=%x msgin=%x msgpriq=%x msgoutq=%x lastmsg=%x "
            "currmsg=%x\n",
            sc->sc_state, sc->sc_imess[0],
            sc->sc_msgpriq, sc->sc_msgoutq, sc->sc_lastmsg, sc->sc_currmsg);
        for (i = 0; i < 7; i++) {
                ti = &sc->sc_tinfo[i];
                printf("tinfo%d: %d cmds %d disconnects %d timeouts",
                    i, ti->cmds, ti->dconns, ti->touts);
                printf(" %d senses flags=%x\n", ti->senses, ti->flags);
        }
}
#endif