/*      $OpenBSD: iha.c,v 1.52 2020/09/22 19:32:52 krw Exp $ */
/*-------------------------------------------------------------------------
 *
 * Device driver for the INI-9XXXU/UW or INIC-940/950  PCI SCSI Controller.
 *
 * Written for 386bsd and FreeBSD by
 *      Winston Hung            <winstonh@initio.com>
 *
 * Copyright (c) 1997-1999 Initio Corp
 * Copyright (c) 2000-2002 Ken Westerback
 *
 * 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,
 *    without modification, immediately at the beginning of the file.
 * 2. 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 OR HIS RELATIVES 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 MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 *
 *-------------------------------------------------------------------------
 */
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/buf.h>
#include <sys/device.h>

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

#include <scsi/scsi_all.h>
#include <scsi/scsiconf.h>
#include <scsi/scsi_message.h>

#include <dev/ic/iha.h>

/* #define IHA_DEBUG_STATE */

/*
 * SCSI Rate Table, indexed by FLAG_SCSI_RATE field of
 * TCS_Flags.
 */
static const u_int8_t iha_rate_tbl[] = {
        /* fast 20                */
        /* nanosecond divide by 4 */
        12,     /* 50ns,  20M     */
        18,     /* 75ns,  13.3M   */
        25,     /* 100ns, 10M     */
        31,     /* 125ns, 8M      */
        37,     /* 150ns, 6.6M    */
        43,     /* 175ns, 5.7M    */
        50,     /* 200ns, 5M      */
        62      /* 250ns, 4M      */
};

int iha_setup_sg_list(struct iha_softc *, struct iha_scb *);
u_int8_t iha_data_over_run(struct iha_scb *);
int iha_push_sense_request(struct iha_softc *, struct iha_scb *);
void iha_timeout(void *);
int  iha_alloc_scbs(struct iha_softc *);
void iha_read_eeprom(bus_space_tag_t, bus_space_handle_t,
                             struct iha_nvram *);
void iha_se2_instr(bus_space_tag_t, bus_space_handle_t, u_int8_t);
u_int16_t iha_se2_rd(bus_space_tag_t, bus_space_handle_t, u_int8_t);
void iha_reset_scsi_bus(struct iha_softc *);
void iha_reset_chip(struct iha_softc *,
                            bus_space_tag_t, bus_space_handle_t);
void iha_reset_dma(bus_space_tag_t, bus_space_handle_t);
void iha_reset_tcs(struct tcs *, u_int8_t);
void iha_print_info(struct iha_softc *, int);
void iha_done_scb(struct iha_softc *, struct iha_scb *);
void iha_exec_scb(struct iha_softc *, struct iha_scb *);
void iha_main(struct iha_softc *, bus_space_tag_t, bus_space_handle_t);
void iha_scsi(struct iha_softc *, bus_space_tag_t, bus_space_handle_t);
int  iha_wait(struct iha_softc *, bus_space_tag_t, bus_space_handle_t,
                      u_int8_t);
void iha_mark_busy_scb(struct iha_scb *);
void *iha_scb_alloc(void *);
void iha_scb_free(void *, void *);
void iha_append_done_scb(struct iha_softc *, struct iha_scb *,
                                 u_int8_t);
struct iha_scb *iha_pop_done_scb(struct iha_softc *);
void iha_append_pend_scb(struct iha_softc *, struct iha_scb *);
void iha_push_pend_scb(struct iha_softc *, struct iha_scb *);
struct iha_scb *iha_find_pend_scb(struct iha_softc *);
void iha_sync_done(struct iha_softc *,
                           bus_space_tag_t, bus_space_handle_t);
void iha_wide_done(struct iha_softc *,
                           bus_space_tag_t, bus_space_handle_t);
void iha_bad_seq(struct iha_softc *);
int  iha_next_state(struct iha_softc *,
                            bus_space_tag_t, bus_space_handle_t);
int  iha_state_1(struct iha_softc *,
                         bus_space_tag_t, bus_space_handle_t);
int  iha_state_2(struct iha_softc *,
                         bus_space_tag_t, bus_space_handle_t);
int  iha_state_3(struct iha_softc *,
                         bus_space_tag_t, bus_space_handle_t);
int  iha_state_4(struct iha_softc *,
                         bus_space_tag_t, bus_space_handle_t);
int  iha_state_5(struct iha_softc *,
                         bus_space_tag_t, bus_space_handle_t);
int  iha_state_6(struct iha_softc *,
                         bus_space_tag_t, bus_space_handle_t);
int  iha_state_8(struct iha_softc *,
                         bus_space_tag_t, bus_space_handle_t);
void iha_set_ssig(bus_space_tag_t,
                          bus_space_handle_t, u_int8_t, u_int8_t);
int  iha_xpad_in(struct iha_softc *,
                         bus_space_tag_t, bus_space_handle_t);
int  iha_xpad_out(struct iha_softc *,
                          bus_space_tag_t, bus_space_handle_t);
int  iha_xfer_data(struct iha_scb *,
                           bus_space_tag_t, bus_space_handle_t,
                           int direction);
int  iha_status_msg(struct iha_softc *,
                            bus_space_tag_t, bus_space_handle_t);
int  iha_msgin(struct iha_softc *, bus_space_tag_t, bus_space_handle_t);
int  iha_msgin_sdtr(struct iha_softc *);
int  iha_msgin_extended(struct iha_softc *,
                                bus_space_tag_t, bus_space_handle_t);
int  iha_msgin_ignore_wid_resid(struct iha_softc *,
                                        bus_space_tag_t, bus_space_handle_t);
int  iha_msgout(struct iha_softc *,
                        bus_space_tag_t, bus_space_handle_t, u_int8_t);
int  iha_msgout_extended(struct iha_softc *,
                                 bus_space_tag_t, bus_space_handle_t);
void iha_msgout_abort(struct iha_softc *,
                              bus_space_tag_t, bus_space_handle_t,  u_int8_t);
int  iha_msgout_reject(struct iha_softc *,
                               bus_space_tag_t, bus_space_handle_t);
int  iha_msgout_sdtr(struct iha_softc *,
                             bus_space_tag_t, bus_space_handle_t);
int  iha_msgout_wdtr(struct iha_softc *,
                             bus_space_tag_t, bus_space_handle_t);
void iha_select(struct iha_softc *,
                        bus_space_tag_t, bus_space_handle_t,
                        struct iha_scb *, u_int8_t);
void iha_busfree(struct iha_softc *,
                         bus_space_tag_t, bus_space_handle_t);
int  iha_resel(struct iha_softc *, bus_space_tag_t, bus_space_handle_t);
void iha_abort_xs(struct iha_softc *, struct scsi_xfer *, u_int8_t);

/*
 * iha_intr - the interrupt service routine for the iha driver
 */
int
iha_intr(void *arg)
{
        bus_space_handle_t ioh;
        struct iha_softc *sc;
        bus_space_tag_t iot;
        int s;

        sc  = (struct iha_softc *)arg;
        iot = sc->sc_iot;
        ioh = sc->sc_ioh;

        if ((bus_space_read_1(iot, ioh, TUL_STAT0) & INTPD) == 0)
                return (0);

        s = splbio(); /* XXX - Or are interrupts off when ISR's are called? */

        if (sc->HCS_Semaph != SEMAPH_IN_MAIN) {
                /* XXX - need these inside a splbio()/splx()? */
                bus_space_write_1(iot, ioh, TUL_IMSK, MASK_ALL);
                sc->HCS_Semaph = SEMAPH_IN_MAIN;

                iha_main(sc, iot, ioh);

                sc->HCS_Semaph = ~SEMAPH_IN_MAIN;
                bus_space_write_1(iot, ioh, TUL_IMSK, (MASK_ALL & ~MSCMP));
        }

        splx(s);

        return (1);
}

/*
 * iha_setup_sg_list -  initialize scatter gather list of pScb from
 *                      pScb->SCB_DataDma.
 */
int
iha_setup_sg_list(struct iha_softc *sc, struct iha_scb *pScb)
{
        bus_dma_segment_t *segs = pScb->SCB_DataDma->dm_segs;
        int i, error, nseg = pScb->SCB_DataDma->dm_nsegs;

        if (nseg > 1) {
                error = bus_dmamap_load(sc->sc_dmat, pScb->SCB_SGDma,
                                pScb->SCB_SGList, sizeof(pScb->SCB_SGList), NULL,
                                (pScb->SCB_Flags & SCSI_NOSLEEP) ?
                                        BUS_DMA_NOWAIT : BUS_DMA_WAITOK);
                if (error) {
                        sc_print_addr(pScb->SCB_Xs->sc_link);
                        printf("error %d loading SG list dma map\n", error);
                        return (error);
                }

                /*
                 * Only set FLAG_SG when SCB_SGDma is loaded so iha_scsi_done
                 * will not unload an unloaded map.
                 */
                pScb->SCB_Flags |= FLAG_SG;
                bzero(pScb->SCB_SGList, sizeof(pScb->SCB_SGList));

                pScb->SCB_SGIdx   = 0;
                pScb->SCB_SGCount = nseg;

                for (i=0; i < nseg; i++) {
                        pScb->SCB_SGList[i].SG_Len  = segs[i].ds_len;
                        pScb->SCB_SGList[i].SG_Addr = segs[i].ds_addr;
                }

                bus_dmamap_sync(sc->sc_dmat, pScb->SCB_SGDma,
                    0, sizeof(pScb->SCB_SGList), BUS_DMASYNC_PREWRITE);
        }

        return (0);
}

/*
 * iha_scsi_cmd - start execution of a SCSI command. This is called
 *                from the generic SCSI driver via the field
 *                sc_adapter.scsi_cmd of iha_softc.
 */
void
iha_scsi_cmd(struct scsi_xfer *xs)
{
        struct iha_scb *pScb;
        struct scsi_link *sc_link = xs->sc_link;
        struct iha_softc *sc = sc_link->bus->sb_adapter_softc;
        int error;

        if ((xs->cmdlen > 12) || (sc_link->target >= IHA_MAX_TARGETS)) {
                xs->error = XS_DRIVER_STUFFUP;
                scsi_done(xs);
                return;
        }

        pScb = xs->io;

        pScb->SCB_Target = sc_link->target;
        pScb->SCB_Lun    = sc_link->lun;
        pScb->SCB_Tcs    = &sc->HCS_Tcs[pScb->SCB_Target];
        pScb->SCB_Flags  = xs->flags;
        pScb->SCB_Ident  = MSG_IDENTIFYFLAG |
                (pScb->SCB_Lun & MSG_IDENTIFY_LUNMASK);

        if ((xs->cmd.opcode != REQUEST_SENSE)
            && ((pScb->SCB_Flags & SCSI_POLL) == 0))
                pScb->SCB_Ident |= MSG_IDENTIFY_DISCFLAG;

        pScb->SCB_Xs     = xs;
        pScb->SCB_CDBLen = xs->cmdlen;
        bcopy(&xs->cmd, &pScb->SCB_CDB, xs->cmdlen);

        pScb->SCB_BufCharsLeft = pScb->SCB_BufChars = xs->datalen;

        if ((pScb->SCB_Flags & (SCSI_DATA_IN | SCSI_DATA_OUT)) != 0) {
                error = bus_dmamap_load(sc->sc_dmat, pScb->SCB_DataDma,
                    xs->data, pScb->SCB_BufChars, NULL,
                    (pScb->SCB_Flags & SCSI_NOSLEEP) ?
                    BUS_DMA_NOWAIT : BUS_DMA_WAITOK);

                if (error) {
                        sc_print_addr(xs->sc_link);
                        if (error == EFBIG)
                                printf("buffer needs >%d dma segments\n",
                                    IHA_MAX_SG_ENTRIES);
                        else
                                printf("error %d loading buffer dma map\n",
                                    error);

                        xs->error = XS_DRIVER_STUFFUP;
                        scsi_done(xs);
                        return;
                }
                bus_dmamap_sync(sc->sc_dmat, pScb->SCB_DataDma,
                    0, pScb->SCB_BufChars,
                    (pScb->SCB_Flags & SCSI_DATA_IN) ?
                    BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);

                error = iha_setup_sg_list(sc, pScb);
                if (error) {
                        bus_dmamap_unload(sc->sc_dmat, pScb->SCB_DataDma);
                        xs->error = XS_DRIVER_STUFFUP;
                        scsi_done(xs);
                        return;
                }

        }

        /*
         * Always initialize the stimeout structure as it may
         * contain garbage that confuses timeout_del() later on.
         * But, timeout_add() ONLY if we are not polling.
         */
        timeout_set(&xs->stimeout, iha_timeout, pScb);

        iha_exec_scb(sc, pScb);
}

/*
 * iha_init_tulip - initialize the inic-940/950 card and the rest of the
 *                  iha_softc structure supplied
 */
int
iha_init_tulip(struct iha_softc *sc)
{
        struct iha_scb *pScb;
        struct iha_nvram_scsi *pScsi;
        bus_space_handle_t ioh;
        struct iha_nvram iha_nvram;
        bus_space_tag_t iot;
        int i, error;

        iot = sc->sc_iot;
        ioh = sc->sc_ioh;

        iha_read_eeprom(iot, ioh, &iha_nvram);

        pScsi = &iha_nvram.NVM_Scsi[0];

        TAILQ_INIT(&sc->HCS_FreeScb);
        TAILQ_INIT(&sc->HCS_PendScb);
        TAILQ_INIT(&sc->HCS_DoneScb);

        mtx_init(&sc->sc_scb_mtx, IPL_BIO);
        scsi_iopool_init(&sc->sc_iopool, sc, iha_scb_alloc, iha_scb_free);

        sc->HCS_Semaph    = ~SEMAPH_IN_MAIN;
        sc->HCS_JSStatus0 = 0;
        sc->HCS_ActScb    = NULL;
        sc->sc_id         = pScsi->NVM_SCSI_Id;
        sc->sc_maxtargets = pScsi->NVM_SCSI_Targets;

        error = iha_alloc_scbs(sc);
        if (error != 0)
                return (error);

        for (i = 0, pScb = sc->HCS_Scb; i < IHA_MAX_SCB; i++, pScb++) {
                pScb->SCB_TagId = i;

                error = bus_dmamap_create(sc->sc_dmat,
                    (IHA_MAX_SG_ENTRIES-1) * PAGE_SIZE, IHA_MAX_SG_ENTRIES,
                    (IHA_MAX_SG_ENTRIES-1) * PAGE_SIZE, 0,
                    BUS_DMA_NOWAIT | BUS_DMA_ALLOCNOW, &pScb->SCB_DataDma);

                if (error != 0) {
                        printf("%s: couldn't create SCB data DMA map, error = %d\n",
                            sc->sc_dev.dv_xname, error);
                        return (error);
                }

                error = bus_dmamap_create(sc->sc_dmat,
                                sizeof(pScb->SCB_SGList), 1,
                                sizeof(pScb->SCB_SGList), 0,
                                BUS_DMA_NOWAIT | BUS_DMA_ALLOCNOW,
                                &pScb->SCB_SGDma);
                if (error != 0) {
                        printf("%s: couldn't create SCB SG DMA map, error = %d\n",
                            sc->sc_dev.dv_xname, error);
                        return (error);
                }

                TAILQ_INSERT_TAIL(&sc->HCS_FreeScb, pScb, SCB_ScbList);
        }

        /* Mask all the interrupts */
        bus_space_write_1(iot, ioh, TUL_IMSK, MASK_ALL);

        /* Stop any I/O and reset the scsi module */
        iha_reset_dma(iot, ioh);
        bus_space_write_1(iot, ioh, TUL_SCTRL0, RSMOD);

        /* Program HBA's SCSI ID */
        bus_space_write_1(iot, ioh, TUL_SID, sc->sc_id << 4);

        /*
         * Configure the channel as requested by the NVRAM settings read
         * into iha_nvram by iha_read_eeprom() above.
         */

        if ((pScsi->NVM_SCSI_Cfg & CFG_EN_PAR) != 0)
                sc->HCS_SConf1 = (SCONFIG0DEFAULT | SPCHK);
        else
                sc->HCS_SConf1 = (SCONFIG0DEFAULT);
        bus_space_write_1(iot, ioh, TUL_SCONFIG0, sc->HCS_SConf1);

        /* selection time out in units of 1.6385 millisecond = 250 ms */
        bus_space_write_1(iot, ioh, TUL_STIMO, 153);

        /* Enable desired SCSI termination configuration read from eeprom */
        bus_space_write_1(iot, ioh, TUL_DCTRL0,
            (pScsi->NVM_SCSI_Cfg & (CFG_ACT_TERM1 | CFG_ACT_TERM2)));

        bus_space_write_1(iot, ioh, TUL_GCTRL1,
            ((pScsi->NVM_SCSI_Cfg & CFG_AUTO_TERM) >> 4)
            | (bus_space_read_1(iot, ioh, TUL_GCTRL1) & (~ATDEN)));

        for (i = 0; i < IHA_MAX_TARGETS; i++) {
                sc->HCS_Tcs[i].TCS_Flags = pScsi->NVM_SCSI_TargetFlags[i];
                iha_reset_tcs(&sc->HCS_Tcs[i], sc->HCS_SConf1);
        }

        iha_reset_chip(sc, iot, ioh);
        bus_space_write_1(iot, ioh, TUL_SIEN, ALL_INTERRUPTS);

        return (0);
}

/*
 * iha_reset_dma - abort any active DMA xfer, reset tulip FIFO.
 */
void
iha_reset_dma(bus_space_tag_t iot, bus_space_handle_t ioh)
{
        if ((bus_space_read_1(iot, ioh, TUL_ISTUS1) & XPEND) != 0) {
                /* if DMA xfer is pending, abort DMA xfer */
                bus_space_write_1(iot, ioh, TUL_DCMD, ABTXFR);
                /* wait Abort DMA xfer done */
                while ((bus_space_read_1(iot, ioh, TUL_ISTUS0) & DABT) == 0)
                        ;
        }

        bus_space_write_1(iot, ioh, TUL_SCTRL0, RSFIFO);
}

/*
 * iha_scb_alloc - return the first free SCB, or NULL if there are none.
 */
void *
iha_scb_alloc(void *xsc)
{
        struct iha_softc *sc = xsc;
        struct iha_scb *pScb;

        mtx_enter(&sc->sc_scb_mtx);
        pScb = TAILQ_FIRST(&sc->HCS_FreeScb);
        if (pScb != NULL) {
                pScb->SCB_Status = STATUS_RENT;
                TAILQ_REMOVE(&sc->HCS_FreeScb, pScb, SCB_ScbList);
        }
        mtx_leave(&sc->sc_scb_mtx);

        return (pScb);
}

/*
 * iha_scb_free - append the supplied SCB to the tail of the
 *                HCS_FreeScb queue after clearing and resetting
 *                everything possible.
 */
void
iha_scb_free(void *xsc, void *xscb)
{
        struct iha_softc *sc = xsc;
        struct iha_scb *pScb = xscb;
        int s;

        s = splbio();
        if (pScb == sc->HCS_ActScb)
                sc->HCS_ActScb = NULL;
        splx(s);

        pScb->SCB_Status = STATUS_QUEUED;
        pScb->SCB_HaStat = HOST_OK;
        pScb->SCB_TaStat = SCSI_OK;

        pScb->SCB_NxtStat  = 0;
        pScb->SCB_Flags    = 0;
        pScb->SCB_Target   = 0;
        pScb->SCB_Lun      = 0;
        pScb->SCB_CDBLen   = 0;
        pScb->SCB_Ident    = 0;
        pScb->SCB_TagMsg   = 0;

        pScb->SCB_BufChars     = 0;
        pScb->SCB_BufCharsLeft = 0;

        pScb->SCB_Xs  = NULL;
        pScb->SCB_Tcs = NULL;

        bzero(pScb->SCB_CDB, sizeof(pScb->SCB_CDB));

        /*
         * SCB_TagId is set at initialization and never changes
         */

        mtx_enter(&sc->sc_scb_mtx);
        TAILQ_INSERT_TAIL(&sc->HCS_FreeScb, pScb, SCB_ScbList);
        mtx_leave(&sc->sc_scb_mtx);
}

void
iha_append_pend_scb(struct iha_softc *sc, struct iha_scb *pScb)
{
        /* ASSUMPTION: only called within a splbio()/splx() pair */

        if (pScb == sc->HCS_ActScb)
                sc->HCS_ActScb = NULL;

        pScb->SCB_Status = STATUS_QUEUED;

        TAILQ_INSERT_TAIL(&sc->HCS_PendScb, pScb, SCB_ScbList);
}

void
iha_push_pend_scb(struct iha_softc *sc, struct iha_scb *pScb)
{
        int s;

        s = splbio();

        if (pScb == sc->HCS_ActScb)
                sc->HCS_ActScb = NULL;

        pScb->SCB_Status = STATUS_QUEUED;

        TAILQ_INSERT_HEAD(&sc->HCS_PendScb, pScb, SCB_ScbList);

        splx(s);
}

/*
 * iha_find_pend_scb - scan the pending queue for a SCB that can be
 *                     processed immediately. Return NULL if none found
 *                     and a pointer to the SCB if one is found. If there
 *                     is an active SCB, return NULL!
 */
struct iha_scb *
iha_find_pend_scb(struct iha_softc *sc)
{
        struct iha_scb *pScb;
        struct tcs *pTcs;
        int s;

        s = splbio();

        if (sc->HCS_ActScb != NULL)
                pScb = NULL;

        else
                TAILQ_FOREACH(pScb, &sc->HCS_PendScb, SCB_ScbList) {
                        if ((pScb->SCB_Flags & SCSI_RESET) != 0)
                                /* ALWAYS willing to reset a device */
                                break;

                        pTcs = pScb->SCB_Tcs;

                        if ((pScb->SCB_TagMsg) != 0) {
                                /*
                                 * A Tagged I/O. OK to start If no
                                 * non-tagged I/O is active on the same
                                 * target
                                 */
                                if (pTcs->TCS_NonTagScb == NULL)
                                        break;

                        } else  if (pScb->SCB_CDB[0] == REQUEST_SENSE) {
                                /*
                                 * OK to do a non-tagged request sense
                                 * even if a non-tagged I/O has been
                                 * started, because we don't allow any
                                 * disconnect during a request sense op
                                 */
                                break;

                        } else  if (pTcs->TCS_TagCnt == 0) {
                                /*
                                 * No tagged I/O active on this target,
                                 * ok to start a non-tagged one if one
                                 * is not already active
                                 */
                                if (pTcs->TCS_NonTagScb == NULL)
                                        break;
                        }
                }

        splx(s);

        return (pScb);
}

void
iha_mark_busy_scb(struct iha_scb *pScb)
{
        int  s;

        s = splbio();

        pScb->SCB_Status = STATUS_BUSY;

        if (pScb->SCB_TagMsg == 0)
                pScb->SCB_Tcs->TCS_NonTagScb = pScb;
        else
                pScb->SCB_Tcs->TCS_TagCnt++;

        splx(s);
}

void
iha_append_done_scb(struct iha_softc *sc, struct iha_scb *pScb, u_int8_t hastat)
{
        struct tcs *pTcs;
        int s;

        s = splbio();

        if (pScb->SCB_Xs != NULL)
                timeout_del(&pScb->SCB_Xs->stimeout);

        if (pScb == sc->HCS_ActScb)
                sc->HCS_ActScb = NULL;

        pTcs = pScb->SCB_Tcs;

        if (pScb->SCB_TagMsg != 0) {
                if (pTcs->TCS_TagCnt)
                        pTcs->TCS_TagCnt--;
        } else if (pTcs->TCS_NonTagScb == pScb)
                pTcs->TCS_NonTagScb = NULL;

        pScb->SCB_Status = STATUS_QUEUED;
        pScb->SCB_HaStat = hastat;

        TAILQ_INSERT_TAIL(&sc->HCS_DoneScb, pScb, SCB_ScbList);

        splx(s);
}

struct iha_scb *
iha_pop_done_scb(struct iha_softc *sc)
{
        struct iha_scb *pScb;
        int s;

        s = splbio();

        pScb = TAILQ_FIRST(&sc->HCS_DoneScb);

        if (pScb != NULL) {
                pScb->SCB_Status = STATUS_RENT;
                TAILQ_REMOVE(&sc->HCS_DoneScb, pScb, SCB_ScbList);
        }

        splx(s);

        return (pScb);
}

/*
 * iha_abort_xs - find the SCB associated with the supplied xs and
 *                stop all processing on it, moving it to the done
 *                queue with the supplied host status value.
 */
void
iha_abort_xs(struct iha_softc *sc, struct scsi_xfer *xs, u_int8_t hastat)
{
        struct iha_scb *pScb, *next;
        int i, s;

        s = splbio();

        /* Check the pending queue for the SCB pointing to xs */

        for (pScb = TAILQ_FIRST(&sc->HCS_PendScb); pScb != NULL; pScb = next) {
                next = TAILQ_NEXT(pScb, SCB_ScbList);
                if (pScb->SCB_Xs == xs) {
                        TAILQ_REMOVE(&sc->HCS_PendScb, pScb, SCB_ScbList);
                        iha_append_done_scb(sc, pScb, hastat);
                        splx(s);
                        return;
                }
        }

        /*
         * If that didn't work, check all BUSY/SELECTING SCB's for one
         * pointing to xs
         */

        for (i = 0, pScb = sc->HCS_Scb; i < IHA_MAX_SCB; i++, pScb++)
                switch (pScb->SCB_Status) {
                case STATUS_BUSY:
                case STATUS_SELECT:
                        if (pScb->SCB_Xs == xs) {
                                iha_append_done_scb(sc, pScb, hastat);
                                splx(s);
                                return;
                        }
                        break;
                default:
                        break;
                }

        splx(s);
}

/*
 * iha_bad_seq - a SCSI bus phase was encountered out of the
 *               correct/expected sequence. Reset the SCSI bus.
 */
void
iha_bad_seq(struct iha_softc *sc)
{
        struct iha_scb *pScb = sc->HCS_ActScb;

        if (pScb != NULL)
                iha_append_done_scb(sc, pScb, HOST_BAD_PHAS);

        iha_reset_scsi_bus(sc);
        iha_reset_chip(sc, sc->sc_iot, sc->sc_ioh);
}

/*
 * iha_push_sense_request - obtain auto sense data by pushing the
 *                          SCB needing it back onto the pending
 *                          queue with a REQUEST_SENSE CDB.
 */
int
iha_push_sense_request(struct iha_softc *sc, struct iha_scb *pScb)
{
        struct scsi_sense *sensecmd;
        int error;

        /* First sync & unload any existing DataDma and SGDma maps */
        if ((pScb->SCB_Flags & (SCSI_DATA_IN | SCSI_DATA_OUT)) != 0) {
                bus_dmamap_sync(sc->sc_dmat, pScb->SCB_DataDma,
                        0, pScb->SCB_BufChars,
                        ((pScb->SCB_Flags & SCSI_DATA_IN) ?
                    BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE));
                bus_dmamap_unload(sc->sc_dmat, pScb->SCB_DataDma);
                /* Don't unload this map again until it is reloaded */
                pScb->SCB_Flags &= ~(SCSI_DATA_IN | SCSI_DATA_OUT);
        }
        if ((pScb->SCB_Flags & FLAG_SG) != 0) {
                bus_dmamap_sync(sc->sc_dmat, pScb->SCB_SGDma,
                        0, sizeof(pScb->SCB_SGList),
                        BUS_DMASYNC_POSTWRITE);
                bus_dmamap_unload(sc->sc_dmat, pScb->SCB_SGDma);
                /* Don't unload this map again until it is reloaded */
                pScb->SCB_Flags &= ~FLAG_SG;
        }

        pScb->SCB_BufChars     = sizeof(pScb->SCB_ScsiSenseData);
        pScb->SCB_BufCharsLeft = sizeof(pScb->SCB_ScsiSenseData);
        bzero(&pScb->SCB_ScsiSenseData, sizeof(pScb->SCB_ScsiSenseData));

        error = bus_dmamap_load(sc->sc_dmat, pScb->SCB_DataDma,
                        &pScb->SCB_ScsiSenseData,
                        sizeof(pScb->SCB_ScsiSenseData), NULL,
                        (pScb->SCB_Flags & SCSI_NOSLEEP) ?
                                BUS_DMA_NOWAIT : BUS_DMA_WAITOK);
        if (error) {
                sc_print_addr(pScb->SCB_Xs->sc_link);
                printf("error %d loading request sense buffer dma map\n",
                        error);
                return (error);
        }
        bus_dmamap_sync(sc->sc_dmat, pScb->SCB_DataDma,
            0, pScb->SCB_BufChars, BUS_DMASYNC_PREREAD);

        /* Save _POLL and _NOSLEEP flags. */
        pScb->SCB_Flags &= SCSI_POLL | SCSI_NOSLEEP;
        pScb->SCB_Flags |= FLAG_RSENS | SCSI_DATA_IN;

        error = iha_setup_sg_list(sc, pScb);
        if (error)
                return (error);

        pScb->SCB_Ident &= ~MSG_IDENTIFY_DISCFLAG;

        pScb->SCB_TagMsg = 0;
        pScb->SCB_TaStat = SCSI_OK;

        bzero(pScb->SCB_CDB, sizeof(pScb->SCB_CDB));

        sensecmd = (struct scsi_sense *)pScb->SCB_CDB;
        pScb->SCB_CDBLen = sizeof(*sensecmd);
        sensecmd->opcode = REQUEST_SENSE;
        sensecmd->byte2  = pScb->SCB_Xs->sc_link->lun << 5;
        sensecmd->length = sizeof(pScb->SCB_ScsiSenseData);

        if ((pScb->SCB_Flags & SCSI_POLL) == 0)
                timeout_add_msec(&pScb->SCB_Xs->stimeout,
                    pScb->SCB_Xs->timeout);

        iha_push_pend_scb(sc, pScb);

        return (0);
}

/*
 * iha_main - process the active SCB, taking one off pending and making it
 *            active if necessary, and any done SCB's created as
 *            a result until there are no interrupts pending and no pending
 *            SCB's that can be started.
 */
void
iha_main(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh)
{
        struct iha_scb *pScb;

        for (;;) {
iha_scsi_label:
                iha_scsi(sc, iot, ioh);

                while ((pScb = iha_pop_done_scb(sc)) != NULL) {

                        switch (pScb->SCB_TaStat) {
                        case SCSI_TERMINATED:
                        case SCSI_ACA_ACTIVE:
                        case SCSI_CHECK:
                                pScb->SCB_Tcs->TCS_Flags &=
                                    ~(FLAG_SYNC_DONE | FLAG_WIDE_DONE);

                                if ((pScb->SCB_Flags & FLAG_RSENS) != 0)
                                        /* Check condition on check condition*/
                                        pScb->SCB_HaStat = HOST_BAD_PHAS;
                                else if (iha_push_sense_request(sc, pScb) != 0)
                                        /* Could not push sense request */
                                        pScb->SCB_HaStat = HOST_BAD_PHAS;
                                else
                                        /* REQUEST SENSE ready to process */
                                        goto iha_scsi_label;
                                break;

                        default:
                                if ((pScb->SCB_Flags & FLAG_RSENS) != 0)
                                        /*
                                         * Return the original SCSI_CHECK, not
                                         * the status of the request sense
                                         * command!
                                         */
                                        pScb->SCB_TaStat = SCSI_CHECK;
                                break;
                        }

                        iha_done_scb(sc, pScb);
                }

                /*
                 * If there are no interrupts pending, or we can't start
                 * a pending sc, break out of the for(;;). Otherwise
                 * continue the good work with another call to
                 * iha_scsi().
                 */
                if (((bus_space_read_1(iot, ioh, TUL_STAT0) & INTPD) == 0)
                    && (iha_find_pend_scb(sc) == NULL))
                        break;
        }
}

/*
 * iha_scsi - service any outstanding interrupts. If there are none, try to
 *            start another SCB currently in the pending queue.
 */
void
iha_scsi(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh)
{
        struct iha_scb *pScb;
        struct tcs *pTcs;
        u_int8_t stat;
        int i;

        /* service pending interrupts asap */

        stat = bus_space_read_1(iot, ioh, TUL_STAT0);
        if ((stat & INTPD) != 0) {
                sc->HCS_JSStatus0 = stat;
                sc->HCS_JSStatus1 = bus_space_read_1(iot, ioh, TUL_STAT1);
                sc->HCS_JSInt     = bus_space_read_1(iot, ioh, TUL_SISTAT);

                sc->HCS_Phase = sc->HCS_JSStatus0 & PH_MASK;

                if ((sc->HCS_JSInt & SRSTD) != 0) {
                        iha_reset_scsi_bus(sc);
                        return;
                }

                if ((sc->HCS_JSInt & RSELED) != 0) {
                        iha_resel(sc, iot, ioh);
                        return;
                }

                if ((sc->HCS_JSInt & (STIMEO | DISCD)) != 0) {
                        iha_busfree(sc, iot, ioh);
                        return;
                }

                if ((sc->HCS_JSInt & (SCMDN | SBSRV)) != 0) {
                        iha_next_state(sc, iot, ioh);
                        return;
                }

                if ((sc->HCS_JSInt & SELED) != 0)
                        iha_set_ssig(iot, ioh, 0, 0);
        }

        /*
         * There were no interrupts pending which required action elsewhere, so
         * see if it is possible to start the selection phase on a pending SCB
         */
        if ((pScb = iha_find_pend_scb(sc)) == NULL)
                return;

        pTcs = pScb->SCB_Tcs;

        /* program HBA's SCSI ID & target SCSI ID */
        bus_space_write_1(iot, ioh, TUL_SID,
            (sc->sc_id << 4) | pScb->SCB_Target);

        if ((pScb->SCB_Flags & SCSI_RESET) == 0) {
                bus_space_write_1(iot, ioh, TUL_SYNCM, pTcs->TCS_JS_Period);

                if (((pTcs->TCS_Flags & FLAG_NO_NEG_WIDE) == 0)
                    ||
                    ((pTcs->TCS_Flags & FLAG_NO_NEG_SYNC) == 0))
                        iha_select(sc, iot, ioh, pScb, SELATNSTOP);

                else if (pScb->SCB_TagMsg != 0)
                        iha_select(sc, iot, ioh, pScb, SEL_ATN3);

                else
                        iha_select(sc, iot, ioh, pScb, SEL_ATN);

        } else {
                iha_select(sc, iot, ioh, pScb, SELATNSTOP);
                pScb->SCB_NxtStat = 8;
        }

        if ((pScb->SCB_Flags & SCSI_POLL) != 0) {
                for (i = pScb->SCB_Xs->timeout; i > 0; i--) {
                        if (iha_wait(sc, iot, ioh, NO_OP) == -1)
                                break;
                        if (iha_next_state(sc, iot, ioh) == -1)
                                break;
                        delay(1000); /* Only happens in boot, so it's ok */
                }

                /*
                 * Since done queue processing not done until AFTER this
                 * function returns, pScb is on the done queue, not
                 * the free queue at this point and still has valid data
                 *
                 * Conversely, xs->error has not been set yet
                 */
                if (i == 0)
                        iha_timeout(pScb);

                else if ((pScb->SCB_CDB[0] == INQUIRY)
                    && (pScb->SCB_Lun == 0)
                    && (pScb->SCB_HaStat == HOST_OK)
                    && (pScb->SCB_TaStat == SCSI_OK))
                        iha_print_info(sc, pScb->SCB_Target);
        }
}

/*
 * iha_data_over_run - return HOST_OK for all SCSI opcodes where BufCharsLeft
 *                     is an 'Allocation Length'. All other SCSI opcodes
 *                     get HOST_DO_DU as they SHOULD have xferred all the
 *                     data requested.
 *
 *                     The list of opcodes using 'Allocation Length' was
 *                     found by scanning all the SCSI-3 T10 drafts. See
 *                     www.t10.org for the curious with a .pdf reader.
 */
u_int8_t
iha_data_over_run(struct iha_scb *pScb)
{
        switch (pScb->SCB_CDB[0]) {
        case 0x03: /* Request Sense                   SPC-2 */
        case 0x12: /* Inquiry                         SPC-2 */
        case 0x1a: /* Mode Sense (6 byte version)     SPC-2 */
        case 0x1c: /* Receive Diagnostic Results      SPC-2 */
        case 0x23: /* Read Format Capacities          MMC-2 */
        case 0x29: /* Read Generation                 SBC   */
        case 0x34: /* Read Position                   SSC-2 */
        case 0x37: /* Read Defect Data                SBC   */
        case 0x3c: /* Read Buffer                     SPC-2 */
        case 0x42: /* Read Sub Channel                MMC-2 */
        case 0x43: /* Read TOC/PMA/ATIP               MMC   */

        /* XXX - 2 with same opcode of 0x44? */
        case 0x44: /* Read Header/Read Density Suprt  MMC/SSC*/

        case 0x46: /* Get Configuration               MMC-2 */
        case 0x4a: /* Get Event/Status Notification   MMC-2 */
        case 0x4d: /* Log Sense                       SPC-2 */
        case 0x51: /* Read Disc Information           MMC   */
        case 0x52: /* Read Track Information          MMC   */
        case 0x59: /* Read Master CUE                 MMC   */
        case 0x5a: /* Mode Sense (10 byte version)    SPC-2 */
        case 0x5c: /* Read Buffer Capacity            MMC   */
        case 0x5e: /* Persistent Reserve In           SPC-2 */
        case 0x84: /* Receive Copy Results            SPC-2 */
        case 0xa0: /* Report LUNs                     SPC-2 */
        case 0xa3: /* Various Report requests         SBC-2/SCC-2*/
        case 0xa4: /* Report Key                      MMC-2 */
        case 0xad: /* Read DVD Structure              MMC-2 */
        case 0xb4: /* Read Element Status (Attached)  SMC   */
        case 0xb5: /* Request Volume Element Address  SMC   */
        case 0xb7: /* Read Defect Data (12 byte ver.) SBC   */
        case 0xb8: /* Read Element Status (Independ.) SMC   */
        case 0xba: /* Report Redundancy               SCC-2 */
        case 0xbd: /* Mechanism Status                MMC   */
        case 0xbe: /* Report Basic Redundancy         SCC-2 */

                return (HOST_OK);
                break;

        default:
                return (HOST_DO_DU);
                break;
        }
}

/*
 * iha_next_state - process the current SCB as requested in its
 *                  SCB_NxtStat member.
 */
int
iha_next_state(struct iha_softc *sc, bus_space_tag_t iot,
    bus_space_handle_t ioh)
{
        if (sc->HCS_ActScb == NULL)
                return (-1);

        switch (sc->HCS_ActScb->SCB_NxtStat) {
        case 1:
                if (iha_state_1(sc, iot, ioh) == 3)
                        goto state_3;
                break;

        case 2:
                switch (iha_state_2(sc, iot, ioh)) {
                case 3:  goto state_3;
                case 4:  goto state_4;
                default: break;
                }
                break;

        case 3:
        state_3:
                if (iha_state_3(sc, iot, ioh) == 4)
                        goto state_4;
                break;

        case 4:
        state_4:
                switch (iha_state_4(sc, iot, ioh)) {
                case 0:  return (0);
                case 6:  goto state_6;
                default: break;
                }
                break;

        case 5:
                switch (iha_state_5(sc, iot, ioh)) {
                case 4:  goto state_4;
                case 6:  goto state_6;
                default: break;
                }
                break;

        case 6:
        state_6:
                iha_state_6(sc, iot, ioh);
                break;

        case 8:
                iha_state_8(sc, iot, ioh);
                break;

        default:
#ifdef IHA_DEBUG_STATE
                sc_print_addr(sc->HCS_ActScb->SCB_Xs->sc_link);
                printf("[debug] -unknown state: %i-\n",
                    sc->HCS_ActScb->SCB_NxtStat);
#endif
                iha_bad_seq(sc);
                break;
        }

        return (-1);
}

/*
 * iha_state_1 - selection is complete after a SELATNSTOP. If the target
 *               has put the bus into MSG_OUT phase start wide/sync
 *               negotiation. Otherwise clear the FIFO and go to state 3,
 *               which will send the SCSI CDB to the target.
 */
int
iha_state_1(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh)
{
        struct iha_scb *pScb = sc->HCS_ActScb;
        struct tcs *pTcs;
        u_int16_t flags;

        iha_mark_busy_scb(pScb);

        pTcs = pScb->SCB_Tcs;

        bus_space_write_1(iot, ioh, TUL_SCONFIG0, pTcs->TCS_SConfig0);

        /*
         * If we are in PHASE_MSG_OUT, send
         *     a) IDENT message (with tags if appropriate)
         *     b) WDTR if the target is configured to negotiate wide xfers
         *     ** OR **
         *     c) SDTR if the target is configured to negotiate sync xfers
         *        but not wide ones
         *
         * If we are NOT, then the target is not asking for anything but
         * the data/command, so go straight to state 3.
         */
        if (sc->HCS_Phase == PHASE_MSG_OUT) {
                bus_space_write_1(iot, ioh, TUL_SCTRL1, (ESBUSIN | EHRSL));
                bus_space_write_1(iot, ioh, TUL_SFIFO,  pScb->SCB_Ident);

                if (pScb->SCB_TagMsg != 0) {
                        bus_space_write_1(iot, ioh, TUL_SFIFO,
                            pScb->SCB_TagMsg);
                        bus_space_write_1(iot, ioh, TUL_SFIFO,
                            pScb->SCB_TagId);
                }

                flags = pTcs->TCS_Flags;
                if ((flags & FLAG_NO_NEG_WIDE) == 0) {
                        if (iha_msgout_wdtr(sc, iot, ioh) == -1)
                                return (-1);
                } else if ((flags & FLAG_NO_NEG_SYNC) == 0) {
                        if (iha_msgout_sdtr(sc, iot, ioh) == -1)
                                return (-1);
                }

        } else {
                bus_space_write_1(iot, ioh, TUL_SCTRL0, RSFIFO);
                iha_set_ssig(iot, ioh, REQ | BSY | SEL | ATN, 0);
        }

        return (3);
}

/*
 * iha_state_2 - selection is complete after a SEL_ATN or SEL_ATN3. If the SCSI
 *               CDB has already been send, go to state 4 to start the data
 *               xfer. Otherwise reset the FIFO and go to state 3, sending
 *               the SCSI CDB.
 */
int
iha_state_2(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh)
{
        struct iha_scb *pScb = sc->HCS_ActScb;

        iha_mark_busy_scb(pScb);

        bus_space_write_1(iot, ioh, TUL_SCONFIG0, pScb->SCB_Tcs->TCS_SConfig0);

        if ((sc->HCS_JSStatus1 & CPDNE) != 0)
                return (4);

        bus_space_write_1(iot, ioh, TUL_SCTRL0, RSFIFO);

        iha_set_ssig(iot, ioh, REQ | BSY | SEL | ATN, 0);

        return (3);
}

/*
 * iha_state_3 - send the SCSI CDB to the target, processing any status
 *               or other messages received until that is done or
 *               abandoned.
 */
int
iha_state_3(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh)
{
        struct iha_scb *pScb = sc->HCS_ActScb;
        u_int16_t flags;

        for (;;)
                switch (sc->HCS_Phase) {
                case PHASE_CMD_OUT:
                        bus_space_write_multi_1(iot, ioh, TUL_SFIFO,
                            pScb->SCB_CDB, pScb->SCB_CDBLen);
                        if (iha_wait(sc, iot, ioh, XF_FIFO_OUT) == -1)
                                return (-1);
                        else if (sc->HCS_Phase == PHASE_CMD_OUT) {
                                iha_bad_seq(sc);
                                return (-1);
                        } else
                                return (4);

                case PHASE_MSG_IN:
                        pScb->SCB_NxtStat = 3;
                        if (iha_msgin(sc, iot, ioh) == -1)
                                return (-1);
                        break;

                case PHASE_STATUS_IN:
                        if (iha_status_msg(sc, iot, ioh) == -1)
                                return (-1);
                        break;

                case PHASE_MSG_OUT:
                        flags = pScb->SCB_Tcs->TCS_Flags;
                        if ((flags & FLAG_NO_NEG_SYNC) != 0) {
                                if (iha_msgout(sc, iot, ioh, MSG_NOOP) == -1)
                                        return (-1);
                        } else if (iha_msgout_sdtr(sc, iot, ioh) == -1)
                                return (-1);
                        break;

                default:
#ifdef IHA_DEBUG_STATE
                        sc_print_addr(pScb->SCB_Xs->sc_link);
                        printf("[debug] -s3- bad phase = %d\n", sc->HCS_Phase);
#endif
                        iha_bad_seq(sc);
                        return (-1);
                }
}

/*
 * iha_state_4 - start a data xfer. Handle any bus state
 *               transitions until PHASE_DATA_IN/_OUT
 *               or the attempt is abandoned. If there is
 *               no data to xfer, go to state 6 and finish
 *               processing the current SCB.
 */
int
iha_state_4(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh)
{
        struct iha_scb *pScb = sc->HCS_ActScb;

        if ((pScb->SCB_Flags & FLAG_DIR) == FLAG_DIR)
                return (6); /* Both dir flags set => NO xfer was requested */

        for (;;) {
                if (pScb->SCB_BufCharsLeft == 0)
                        return (6);

                switch (sc->HCS_Phase) {
                case PHASE_STATUS_IN:
                        if ((pScb->SCB_Flags & FLAG_DIR) != 0)
                                pScb->SCB_HaStat = iha_data_over_run(pScb);
                        if ((iha_status_msg(sc, iot, ioh)) == -1)
                                return (-1);
                        break;

                case PHASE_MSG_IN:
                        pScb->SCB_NxtStat = 4;
                        if (iha_msgin(sc, iot, ioh) == -1)
                                return (-1);
                        break;

                case PHASE_MSG_OUT:
                        if ((sc->HCS_JSStatus0 & SPERR) != 0) {
                                pScb->SCB_BufCharsLeft = 0;
                                pScb->SCB_HaStat = HOST_SPERR;
                                if (iha_msgout(sc, iot, ioh,
                                        MSG_INITIATOR_DET_ERR) == -1)
                                        return (-1);
                                else
                                        return (6);
                        } else {
                                if (iha_msgout(sc, iot, ioh, MSG_NOOP) == -1)
                                        return (-1);
                        }
                        break;

                case PHASE_DATA_IN:
                        return (iha_xfer_data(pScb, iot, ioh, SCSI_DATA_IN));

                case PHASE_DATA_OUT:
                        return (iha_xfer_data(pScb, iot, ioh, SCSI_DATA_OUT));

                default:
                        iha_bad_seq(sc);
                        return (-1);
                }
        }
}

/*
 * iha_state_5 - handle the partial or final completion of the current
 *               data xfer. If DMA is still active stop it. If there is
 *               more data to xfer, go to state 4 and start the xfer.
 *               If not go to state 6 and finish the SCB.
 */
int
iha_state_5(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh)
{
        struct iha_scb *pScb = sc->HCS_ActScb;
        struct iha_sg_element *pSg;
        u_int32_t cnt;
        u_int16_t period;
        u_int8_t stat;
        long xcnt;  /* cannot use unsigned!! see code: if (xcnt < 0) */

        cnt = bus_space_read_4(iot, ioh, TUL_STCNT0) & TCNT;

        /*
         * Stop any pending DMA activity and check for parity error.
         */

        if ((bus_space_read_1(iot, ioh, TUL_DCMD) & XDIR) != 0) {
                /* Input Operation */
                if ((sc->HCS_JSStatus0 & SPERR) != 0)
                        pScb->SCB_HaStat = HOST_SPERR;

                if ((bus_space_read_1(iot, ioh, TUL_ISTUS1) & XPEND) != 0) {
                        bus_space_write_1(iot, ioh, TUL_DCTRL0,
                            bus_space_read_1(iot, ioh, TUL_DCTRL0) | SXSTP);
                        while (bus_space_read_1(iot, ioh, TUL_ISTUS1) & XPEND)
                                ;
                }

        } else {
                /* Output Operation */
                if ((sc->HCS_JSStatus1 & SXCMP) == 0) {
                        period = pScb->SCB_Tcs->TCS_JS_Period;
                        if ((period & PERIOD_WIDE_SCSI) != 0)
                                cnt += (bus_space_read_1(iot, ioh,
                                            TUL_SFIFOCNT) & FIFOC) << 1;
                        else
                                cnt += (bus_space_read_1(iot, ioh,
                                            TUL_SFIFOCNT) & FIFOC);
                }

                if ((bus_space_read_1(iot, ioh, TUL_ISTUS1) & XPEND) != 0) {
                        bus_space_write_1(iot, ioh, TUL_DCMD, ABTXFR);
                        do
                                stat = bus_space_read_1(iot, ioh, TUL_ISTUS0);
                        while ((stat & DABT) == 0);
                }

                if ((cnt == 1) && (sc->HCS_Phase == PHASE_DATA_OUT)) {
                        if (iha_wait(sc, iot, ioh, XF_FIFO_OUT) == -1)
                                return (-1);
                        cnt = 0;

                } else if ((sc->HCS_JSStatus1 & SXCMP) == 0)
                        bus_space_write_1(iot, ioh, TUL_SCTRL0, RSFIFO);
        }

        if (cnt == 0) {
                pScb->SCB_BufCharsLeft = 0;
                return (6);
        }

        /* Update active data pointer and restart the I/O at the new point */

        xcnt = pScb->SCB_BufCharsLeft - cnt;    /* xcnt == bytes xferred */
        pScb->SCB_BufCharsLeft = cnt;           /* cnt  == bytes left    */

        bus_dmamap_sync(sc->sc_dmat, pScb->SCB_SGDma,
            0, sizeof(pScb->SCB_SGList), BUS_DMASYNC_POSTWRITE);

        if ((pScb->SCB_Flags & FLAG_SG) != 0) {
                pSg = &pScb->SCB_SGList[pScb->SCB_SGIdx];
                for (; pScb->SCB_SGIdx < pScb->SCB_SGCount; pSg++, pScb->SCB_SGIdx++) {
                        xcnt -= pSg->SG_Len;
                        if (xcnt < 0) {
                                xcnt += pSg->SG_Len;

                                pSg->SG_Addr += xcnt;
                                pSg->SG_Len -= xcnt;

                                bus_dmamap_sync(sc->sc_dmat, pScb->SCB_SGDma,
                                    0, sizeof(pScb->SCB_SGList),
                                        BUS_DMASYNC_PREWRITE);

                                return (4);
                        }
                }
                return (6);

        }

        return (4);
}

/*
 * iha_state_6 - finish off the active scb (may require several
 *               iterations if PHASE_MSG_IN) and return -1 to indicate
 *               the bus is free.
 */
int
iha_state_6(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh)
{
        for (;;)
                switch (sc->HCS_Phase) {
                case PHASE_STATUS_IN:
                        if (iha_status_msg(sc, iot, ioh) == -1)
                                return (-1);
                        break;

                case PHASE_MSG_IN:
                        sc->HCS_ActScb->SCB_NxtStat = 6;
                        if ((iha_msgin(sc, iot, ioh)) == -1)
                                return (-1);
                        break;

                case PHASE_MSG_OUT:
                        if ((iha_msgout(sc, iot, ioh, MSG_NOOP)) == -1)
                                return (-1);
                        break;

                case PHASE_DATA_IN:
                        if (iha_xpad_in(sc, iot, ioh) == -1)
                                return (-1);
                        break;

                case PHASE_DATA_OUT:
                        if (iha_xpad_out(sc, iot, ioh) == -1)
                                return (-1);
                        break;

                default:
                        iha_bad_seq(sc);
                        return (-1);
                }
}

/*
 * iha_state_8 - reset the active device and all busy SCBs using it
 */
int
iha_state_8(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh)
{
        struct iha_scb *pScb;
        u_int32_t i;
        u_int8_t tar;

        if (sc->HCS_Phase == PHASE_MSG_OUT) {
                bus_space_write_1(iot, ioh, TUL_SFIFO, MSG_BUS_DEV_RESET);

                pScb = sc->HCS_ActScb;

                /* This SCB finished correctly -- resetting the device */
                iha_append_done_scb(sc, pScb, HOST_OK);

                iha_reset_tcs(pScb->SCB_Tcs, sc->HCS_SConf1);

                tar = pScb->SCB_Target;
                for (i = 0, pScb = sc->HCS_Scb; i < IHA_MAX_SCB; i++, pScb++)
                        if (pScb->SCB_Target == tar)
                                switch (pScb->SCB_Status) {
                                case STATUS_BUSY:
                                        iha_append_done_scb(sc,
                                            pScb, HOST_DEV_RST);
                                        break;

                                case STATUS_SELECT:
                                        iha_push_pend_scb(sc, pScb);
                                        break;

                                default:
                                        break;
                                }

                sc->HCS_Flags |= FLAG_EXPECT_DISC;

                if (iha_wait(sc, iot, ioh, XF_FIFO_OUT) == -1)
                        return (-1);
        }

        iha_bad_seq(sc);
        return (-1);
}

/*
 * iha_xfer_data - initiate the DMA xfer of the data
 */
int
iha_xfer_data(struct iha_scb *pScb, bus_space_tag_t iot, bus_space_handle_t ioh,
    int direction)
{
        u_int32_t xferaddr, xferlen;
        u_int8_t xfertype;

        if ((pScb->SCB_Flags & FLAG_DIR) != direction)
                return (6); /* wrong direction, abandon I/O */

        bus_space_write_4(iot, ioh, TUL_STCNT0, pScb->SCB_BufCharsLeft);

        if ((pScb->SCB_Flags & FLAG_SG) == 0) {
                xferaddr = pScb->SCB_DataDma->dm_segs[0].ds_addr
                                + (pScb->SCB_BufChars - pScb->SCB_BufCharsLeft);
                xferlen  = pScb->SCB_BufCharsLeft;
                xfertype = (direction == SCSI_DATA_IN) ? ST_X_IN : ST_X_OUT;

        } else {
                xferaddr = pScb->SCB_SGDma->dm_segs[0].ds_addr
                                + (pScb->SCB_SGIdx * sizeof(struct iha_sg_element));
                xferlen  = (pScb->SCB_SGCount - pScb->SCB_SGIdx)
                                * sizeof(struct iha_sg_element);
                xfertype = (direction == SCSI_DATA_IN) ? ST_SG_IN : ST_SG_OUT;
        }

        bus_space_write_4(iot, ioh, TUL_DXC,  xferlen);
        bus_space_write_4(iot, ioh, TUL_DXPA, xferaddr);
        bus_space_write_1(iot, ioh, TUL_DCMD, xfertype);

        bus_space_write_1(iot, ioh, TUL_SCMD,
            (direction == SCSI_DATA_IN) ? XF_DMA_IN : XF_DMA_OUT);

        pScb->SCB_NxtStat = 5;

        return (0);
}

int
iha_xpad_in(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh)
{
        struct iha_scb *pScb = sc->HCS_ActScb;

        if ((pScb->SCB_Flags & FLAG_DIR) != 0)
                pScb->SCB_HaStat = HOST_DO_DU;

        for (;;) {
                if ((pScb->SCB_Tcs->TCS_JS_Period & PERIOD_WIDE_SCSI) != 0)
                        bus_space_write_4(iot, ioh, TUL_STCNT0, 2);
                else
                        bus_space_write_4(iot, ioh, TUL_STCNT0, 1);

                switch (iha_wait(sc, iot, ioh, XF_FIFO_IN)) {
                case -1:
                        return (-1);

                case PHASE_DATA_IN:
                        bus_space_read_1(iot, ioh, TUL_SFIFO);
                        break;

                default:
                        bus_space_write_1(iot, ioh, TUL_SCTRL0, RSFIFO);
                        return (6);
                }
        }
}

int
iha_xpad_out(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh)
{
        struct iha_scb *pScb = sc->HCS_ActScb;

        if ((pScb->SCB_Flags & FLAG_DIR) != 0)
                pScb->SCB_HaStat = HOST_DO_DU;

        for (;;) {
                if ((pScb->SCB_Tcs->TCS_JS_Period & PERIOD_WIDE_SCSI) != 0)
                        bus_space_write_4(iot, ioh, TUL_STCNT0, 2);
                else
                        bus_space_write_4(iot, ioh, TUL_STCNT0, 1);

                bus_space_write_1(iot, ioh, TUL_SFIFO, 0);

                switch (iha_wait(sc, iot, ioh, XF_FIFO_OUT)) {
                case -1:
                        return (-1);

                case PHASE_DATA_OUT:
                        break;

                default:
                        /* Disable wide CPU to allow read 16 bits */
                        bus_space_write_1(iot, ioh, TUL_SCTRL1, EHRSL);
                        bus_space_write_1(iot, ioh, TUL_SCTRL0, RSFIFO);
                        return (6);
                }
        }
}

int
iha_status_msg(struct iha_softc *sc, bus_space_tag_t iot,
    bus_space_handle_t ioh)
{
        struct iha_scb *pScb;
        u_int8_t msg;
        int phase;

        if ((phase = iha_wait(sc, iot, ioh, CMD_COMP)) == -1)
                return (-1);

        pScb = sc->HCS_ActScb;

        pScb->SCB_TaStat = bus_space_read_1(iot, ioh, TUL_SFIFO);

        if (phase == PHASE_MSG_OUT) {
                if ((sc->HCS_JSStatus0 & SPERR) == 0)
                        bus_space_write_1(iot, ioh, TUL_SFIFO,
                            MSG_NOOP);
                else
                        bus_space_write_1(iot, ioh, TUL_SFIFO,
                            MSG_PARITY_ERROR);

                return (iha_wait(sc, iot, ioh, XF_FIFO_OUT));

        } else if (phase == PHASE_MSG_IN) {
                msg = bus_space_read_1(iot, ioh, TUL_SFIFO);

                if ((sc->HCS_JSStatus0 & SPERR) != 0)
                        switch (iha_wait(sc, iot, ioh, MSG_ACCEPT)) {
                        case -1:
                                return (-1);
                        case PHASE_MSG_OUT:
                                bus_space_write_1(iot, ioh, TUL_SFIFO,
                                    MSG_PARITY_ERROR);
                                return (iha_wait(sc, iot, ioh, XF_FIFO_OUT));
                        default:
                                iha_bad_seq(sc);
                                return (-1);
                        }

                if (msg == MSG_CMDCOMPLETE) {
                        if ((pScb->SCB_TaStat
                            & (SCSI_INTERM | SCSI_BUSY)) == SCSI_INTERM) {
                                iha_bad_seq(sc);
                                return (-1);
                        }
                        sc->HCS_Flags |= FLAG_EXPECT_DONE_DISC;
                        bus_space_write_1(iot, ioh, TUL_SCTRL0, RSFIFO);
                        return (iha_wait(sc, iot, ioh, MSG_ACCEPT));
                }

                if ((msg == MSG_LINK_CMD_COMPLETE)
                    || (msg == MSG_LINK_CMD_COMPLETEF)) {
                        if ((pScb->SCB_TaStat
                            & (SCSI_INTERM | SCSI_BUSY)) == SCSI_INTERM)
                                return (iha_wait(sc, iot, ioh, MSG_ACCEPT));
                }
        }

        iha_bad_seq(sc);
        return (-1);
}

/*
 * iha_busfree - SCSI bus free detected as a result of a TIMEOUT or
 *               DISCONNECT interrupt. Reset the tulip FIFO and
 *               SCONFIG0 and enable hardware reselect. Move any active
 *               SCB to HCS_DoneScb list. Return an appropriate host status
 *               if an I/O was active.
 */
void
iha_busfree(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh)
{
        struct iha_scb *pScb;

        bus_space_write_1(iot, ioh, TUL_SCTRL0,   RSFIFO);
        bus_space_write_1(iot, ioh, TUL_SCONFIG0, SCONFIG0DEFAULT);
        bus_space_write_1(iot, ioh, TUL_SCTRL1,   EHRSL);

        pScb = sc->HCS_ActScb;

        if (pScb != NULL) {
                if (pScb->SCB_Status == STATUS_SELECT)
                        /* selection timeout   */
                        iha_append_done_scb(sc, pScb, HOST_SEL_TOUT);
                else
                        /* Unexpected bus free */
                        iha_append_done_scb(sc, pScb, HOST_BAD_PHAS);

        }
}

void
iha_reset_scsi_bus(struct iha_softc *sc)
{
        struct iha_scb *pScb;
        struct tcs *pTcs;
        int i, s;

        s = splbio();

        iha_reset_dma(sc->sc_iot, sc->sc_ioh);

        for (i = 0, pScb = sc->HCS_Scb; i < IHA_MAX_SCB; i++, pScb++)
                switch (pScb->SCB_Status) {
                case STATUS_BUSY:
                        iha_append_done_scb(sc, pScb, HOST_SCSI_RST);
                        break;

                case STATUS_SELECT:
                        iha_push_pend_scb(sc, pScb);
                        break;

                default:
                        break;
                }

        for (i = 0, pTcs = sc->HCS_Tcs; i < IHA_MAX_TARGETS; i++, pTcs++)
                iha_reset_tcs(pTcs, sc->HCS_SConf1);

        splx(s);
}

/*
 * iha_resel - handle a detected SCSI bus reselection request.
 */
int
iha_resel(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh)
{
        struct iha_scb *pScb;
        struct tcs *pTcs;
        u_int8_t tag, target, lun, msg, abortmsg;

        if (sc->HCS_ActScb != NULL) {
                if (sc->HCS_ActScb->SCB_Status == STATUS_SELECT)
                        iha_push_pend_scb(sc, sc->HCS_ActScb);
                sc->HCS_ActScb = NULL;
        }

        target = bus_space_read_1(iot, ioh, TUL_SBID);
        lun    = bus_space_read_1(iot, ioh, TUL_SALVC) & MSG_IDENTIFY_LUNMASK;

        pTcs = &sc->HCS_Tcs[target];

        bus_space_write_1(iot, ioh, TUL_SCONFIG0, pTcs->TCS_SConfig0);
        bus_space_write_1(iot, ioh, TUL_SYNCM,    pTcs->TCS_JS_Period);

        abortmsg = MSG_ABORT; /* until a valid tag has been obtained */

        if (pTcs->TCS_NonTagScb != NULL)
                /* There is a non-tagged I/O active on the target */
                pScb = pTcs->TCS_NonTagScb;

        else {
                /*
                 * Since there is no active non-tagged operation
                 * read the tag type, the tag itself, and find
                 * the appropriate pScb by indexing HCS_Scb with
                 * the tag.
                 */

                switch (iha_wait(sc, iot, ioh, MSG_ACCEPT)) {
                case -1:
                        return (-1);
                case PHASE_MSG_IN:
                        bus_space_write_4(iot, ioh, TUL_STCNT0, 1);
                        if ((iha_wait(sc, iot, ioh, XF_FIFO_IN)) == -1)
                                return (-1);
                        break;
                default:
                        goto abort;
                }

                msg = bus_space_read_1(iot, ioh, TUL_SFIFO); /* Read Tag Msg */

                if ((msg < MSG_SIMPLE_Q_TAG) || (msg > MSG_ORDERED_Q_TAG))
                        goto abort;

                switch (iha_wait(sc, iot, ioh, MSG_ACCEPT)) {
                case -1:
                        return (-1);
                case PHASE_MSG_IN:
                        bus_space_write_4(iot, ioh, TUL_STCNT0, 1);
                        if ((iha_wait(sc, iot, ioh, XF_FIFO_IN)) == -1)
                                return (-1);
                        break;
                default:
                        goto abort;
                }

                tag  = bus_space_read_1(iot, ioh, TUL_SFIFO); /* Read Tag ID */
                pScb = &sc->HCS_Scb[tag];

                abortmsg = MSG_ABORT_TAG; /* Now that we have valdid tag! */
        }

        if ((pScb->SCB_Target != target)
            || (pScb->SCB_Lun != lun)
            || (pScb->SCB_Status != STATUS_BUSY)) {
abort:
                iha_msgout_abort(sc, iot, ioh, abortmsg);
                return (-1);
        }

        sc->HCS_ActScb = pScb;

        if (iha_wait(sc, iot, ioh, MSG_ACCEPT) == -1)
                return (-1);

        return(iha_next_state(sc, iot, ioh));
}

int
iha_msgin(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh)
{
        u_int16_t flags;
        u_int8_t msg;
        int phase;

        for (;;) {
                if ((bus_space_read_1(iot, ioh, TUL_SFIFOCNT) & FIFOC) > 0)
                        bus_space_write_1(iot, ioh, TUL_SCTRL0, RSFIFO);

                bus_space_write_4(iot, ioh, TUL_STCNT0, 1);

                phase = iha_wait(sc, iot, ioh, XF_FIFO_IN);
                msg   = bus_space_read_1(iot, ioh, TUL_SFIFO);

                switch (msg) {
                case MSG_DISCONNECT:
                        sc->HCS_Flags |= FLAG_EXPECT_DISC;
                        if (iha_wait(sc, iot, ioh, MSG_ACCEPT) != -1)
                                iha_bad_seq(sc);
                        phase = -1;
                        break;
                case MSG_SAVEDATAPOINTER:
                case MSG_RESTOREPOINTERS:
                case MSG_NOOP:
                        phase = iha_wait(sc, iot, ioh, MSG_ACCEPT);
                        break;
                case MSG_MESSAGE_REJECT:
                        /* XXX - need to clear FIFO like other 'Clear ATN'?*/
                        iha_set_ssig(iot, ioh, REQ | BSY | SEL | ATN, 0);
                        flags = sc->HCS_ActScb->SCB_Tcs->TCS_Flags;
                        if ((flags & FLAG_NO_NEG_SYNC) == 0)
                                iha_set_ssig(iot, ioh, REQ | BSY | SEL, ATN);
                        phase = iha_wait(sc, iot, ioh, MSG_ACCEPT);
                        break;
                case MSG_EXTENDED:
                        phase = iha_msgin_extended(sc, iot, ioh);
                        break;
                case MSG_IGN_WIDE_RESIDUE:
                        phase = iha_msgin_ignore_wid_resid(sc, iot, ioh);
                        break;
                case MSG_CMDCOMPLETE:
                        sc->HCS_Flags |= FLAG_EXPECT_DONE_DISC;
                        bus_space_write_1(iot, ioh, TUL_SCTRL0, RSFIFO);
                        phase = iha_wait(sc, iot, ioh, MSG_ACCEPT);
                        if (phase != -1) {
                                iha_bad_seq(sc);
                                return (-1);
                        }
                        break;
                default:
#ifdef IHA_DEBUG_STATE
                        printf("[debug] iha_msgin: bad msg type: %d\n", msg);
#endif
                        phase = iha_msgout_reject(sc, iot, ioh);
                        break;
                }

                if (phase != PHASE_MSG_IN)
                        return (phase);
        }
        /* NOTREACHED */
}

int
iha_msgin_ignore_wid_resid(struct iha_softc *sc, bus_space_tag_t iot,
    bus_space_handle_t ioh)
{
        int phase;

        phase = iha_wait(sc, iot, ioh, MSG_ACCEPT);

        if (phase == PHASE_MSG_IN) {
                phase = iha_wait(sc, iot, ioh, XF_FIFO_IN);

                if (phase != -1) {
                        bus_space_write_1(iot, ioh, TUL_SFIFO, 0);
                        bus_space_read_1 (iot, ioh, TUL_SFIFO);
                        bus_space_read_1 (iot, ioh, TUL_SFIFO);

                        phase = iha_wait(sc, iot, ioh, MSG_ACCEPT);
                }
        }

        return (phase);
}

int
iha_msgin_extended(struct iha_softc *sc, bus_space_tag_t iot,
    bus_space_handle_t ioh)
{
        u_int16_t flags;
        int i, phase, msglen, msgcode;

        /* XXX - can we just stop reading and reject, or do we have to
         *       read all input, discarding the excess, and then reject
         */
        for (i = 0; i < IHA_MAX_EXTENDED_MSG; i++) {
                phase = iha_wait(sc, iot, ioh, MSG_ACCEPT);

                if (phase != PHASE_MSG_IN)
                        return (phase);

                bus_space_write_4(iot, ioh, TUL_STCNT0, 1);

                if (iha_wait(sc, iot, ioh, XF_FIFO_IN) == -1)
                        return (-1);

                sc->HCS_Msg[i] = bus_space_read_1(iot, ioh, TUL_SFIFO);

                if (sc->HCS_Msg[0] == i)
                        break;
        }

        msglen  = sc->HCS_Msg[0];
        msgcode = sc->HCS_Msg[1];

        if ((msglen == MSG_EXT_SDTR_LEN) && (msgcode == MSG_EXT_SDTR)) {
                if (iha_msgin_sdtr(sc) == 0) {
                        iha_sync_done(sc, iot, ioh);
                        return (iha_wait(sc, iot, ioh, MSG_ACCEPT));
                }

                iha_set_ssig(iot, ioh, REQ | BSY | SEL, ATN);

                phase = iha_wait(sc, iot, ioh, MSG_ACCEPT);
                if (phase != PHASE_MSG_OUT)
                        return (phase);

                /* Clear FIFO for important message - final SYNC offer */
                bus_space_write_1(iot, ioh, TUL_SCTRL0, RSFIFO);

                iha_sync_done(sc, iot, ioh); /* This is our final offer */

        } else if ((msglen == MSG_EXT_WDTR_LEN) && (msgcode == MSG_EXT_WDTR)) {

                flags = sc->HCS_ActScb->SCB_Tcs->TCS_Flags;

                if ((flags & FLAG_NO_WIDE) != 0)
                        /* Offer 8 bit xfers only */
                        sc->HCS_Msg[2] = MSG_EXT_WDTR_BUS_8_BIT;

                else if (sc->HCS_Msg[2] > MSG_EXT_WDTR_BUS_32_BIT)
                        return (iha_msgout_reject(sc, iot, ioh));

                else if (sc->HCS_Msg[2] == MSG_EXT_WDTR_BUS_32_BIT)
                        /* Offer 16 instead */
                        sc->HCS_Msg[2] = MSG_EXT_WDTR_BUS_32_BIT;

                else {
                        iha_wide_done(sc, iot, ioh);
                        if ((flags & FLAG_NO_NEG_SYNC) == 0)
                                iha_set_ssig(iot, ioh, REQ | BSY | SEL, ATN);
                        return (iha_wait(sc, iot, ioh, MSG_ACCEPT));
                }

                iha_set_ssig(iot, ioh, REQ | BSY | SEL, ATN);

                phase = iha_wait(sc, iot, ioh, MSG_ACCEPT);
                if (phase != PHASE_MSG_OUT)
                        return (phase);

        } else
                return (iha_msgout_reject(sc, iot, ioh));

        /* Send message built in sc->HCS_Msg[] */
        return (iha_msgout_extended(sc, iot, ioh));
}

/*
 * iha_msgin_sdtr - check SDTR msg in HCS_Msg. If the offer is
 *                  acceptable leave HCS_Msg as is and return 0.
 *                  If the negotiation must continue, modify HCS_Msg
 *                  as needed and return 1. Else return 0.
 */
int
iha_msgin_sdtr(struct iha_softc *sc)
{
        u_int16_t flags;
        u_int8_t default_period;
        int newoffer;

        flags = sc->HCS_ActScb->SCB_Tcs->TCS_Flags;

        default_period = iha_rate_tbl[flags & FLAG_SCSI_RATE];

        if (sc->HCS_Msg[3] == 0) /* target offered async only. Accept it. */
                return (0);

        newoffer = 0;

        if ((flags & FLAG_NO_SYNC) != 0) {
                sc->HCS_Msg[3] = 0;
                newoffer   = 1;
        }

        if (sc->HCS_Msg[3] > IHA_MAX_TARGETS-1) {
                sc->HCS_Msg[3] = IHA_MAX_TARGETS-1;
                newoffer   = 1;
        }

        if (sc->HCS_Msg[2] < default_period) {
                sc->HCS_Msg[2] = default_period;
                newoffer   = 1;
        }

        if (sc->HCS_Msg[2] >= 59) {
                sc->HCS_Msg[3] = 0;
                newoffer   = 1;
        }

        return (newoffer);
}

int
iha_msgout(struct iha_softc *sc, bus_space_tag_t iot,
    bus_space_handle_t ioh, u_int8_t msg)
{
        bus_space_write_1(iot, ioh, TUL_SFIFO, msg);

        return (iha_wait(sc, iot, ioh, XF_FIFO_OUT));
}

void
iha_msgout_abort(struct iha_softc *sc, bus_space_tag_t iot,
    bus_space_handle_t ioh, u_int8_t aborttype)
{
        iha_set_ssig(iot, ioh, REQ | BSY | SEL, ATN);

        switch (iha_wait(sc, iot, ioh, MSG_ACCEPT)) {
        case -1:
                break;

        case PHASE_MSG_OUT:
                sc->HCS_Flags |= FLAG_EXPECT_DISC;
                if (iha_msgout(sc, iot, ioh, aborttype) != -1)
                        iha_bad_seq(sc);
                break;

        default:
                iha_bad_seq(sc);
                break;
        }
}

int
iha_msgout_reject(struct iha_softc *sc, bus_space_tag_t iot,
    bus_space_handle_t ioh)
{
        iha_set_ssig(iot, ioh, REQ | BSY | SEL, ATN);

        if (iha_wait(sc, iot, ioh, MSG_ACCEPT) == PHASE_MSG_OUT)
                return (iha_msgout(sc, iot, ioh, MSG_MESSAGE_REJECT));

        return (-1);
}

int
iha_msgout_extended(struct iha_softc *sc, bus_space_tag_t iot,
    bus_space_handle_t ioh)
{
        int phase;

        bus_space_write_1(iot, ioh, TUL_SFIFO, MSG_EXTENDED);

        bus_space_write_multi_1(iot, ioh, TUL_SFIFO,
            sc->HCS_Msg, sc->HCS_Msg[0]+1);

        phase = iha_wait(sc, iot, ioh, XF_FIFO_OUT);

        bus_space_write_1(iot, ioh, TUL_SCTRL0, RSFIFO);
        iha_set_ssig(iot, ioh, REQ | BSY | SEL | ATN, 0);

        return (phase);
}

int
iha_msgout_wdtr(struct iha_softc *sc, bus_space_tag_t iot,
    bus_space_handle_t ioh)
{
        sc->HCS_ActScb->SCB_Tcs->TCS_Flags |= FLAG_WIDE_DONE;

        sc->HCS_Msg[0] = MSG_EXT_WDTR_LEN;
        sc->HCS_Msg[1] = MSG_EXT_WDTR;
        sc->HCS_Msg[2] = MSG_EXT_WDTR_BUS_16_BIT;

        return (iha_msgout_extended(sc, iot, ioh));
}

int
iha_msgout_sdtr(struct iha_softc *sc, bus_space_tag_t iot,
    bus_space_handle_t ioh)
{
        u_int16_t rateindex;
        u_int8_t sync_rate;

        rateindex = sc->HCS_ActScb->SCB_Tcs->TCS_Flags & FLAG_SCSI_RATE;

        sync_rate = iha_rate_tbl[rateindex];

        sc->HCS_Msg[0] = MSG_EXT_SDTR_LEN;
        sc->HCS_Msg[1] = MSG_EXT_SDTR;
        sc->HCS_Msg[2] = sync_rate;
        sc->HCS_Msg[3] = IHA_MAX_TARGETS-1; /* REQ/ACK */

        return (iha_msgout_extended(sc, iot, ioh));
}

void
iha_wide_done(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh)
{
        struct tcs *pTcs = sc->HCS_ActScb->SCB_Tcs;

        pTcs->TCS_JS_Period = 0;

        if (sc->HCS_Msg[2] != 0)
                pTcs->TCS_JS_Period |= PERIOD_WIDE_SCSI;

        pTcs->TCS_SConfig0 &= ~ALTPD;
        pTcs->TCS_Flags    &= ~FLAG_SYNC_DONE;
        pTcs->TCS_Flags    |=  FLAG_WIDE_DONE;

        bus_space_write_1(iot, ioh, TUL_SCONFIG0, pTcs->TCS_SConfig0);
        bus_space_write_1(iot, ioh, TUL_SYNCM,    pTcs->TCS_JS_Period);
}

void
iha_sync_done(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh)
{
        struct tcs *pTcs = sc->HCS_ActScb->SCB_Tcs;
        int i;

        if ((pTcs->TCS_Flags & FLAG_SYNC_DONE) == 0) {
                if (sc->HCS_Msg[3] != 0) {
                        pTcs->TCS_JS_Period |= sc->HCS_Msg[3];

                        /* pick the highest possible rate */
                        for (i = 0; i < sizeof(iha_rate_tbl); i++)
                                if (iha_rate_tbl[i] >= sc->HCS_Msg[2])
                                        break;

                        pTcs->TCS_JS_Period |= (i << 4);
                        pTcs->TCS_SConfig0  |= ALTPD;
                }

                pTcs->TCS_Flags |= FLAG_SYNC_DONE;

                bus_space_write_1(iot, ioh, TUL_SCONFIG0, pTcs->TCS_SConfig0);
                bus_space_write_1(iot, ioh, TUL_SYNCM,    pTcs->TCS_JS_Period);
        }
}

void
iha_reset_chip(struct iha_softc *sc, bus_space_tag_t iot,
    bus_space_handle_t ioh)
{
        int i;

        /* reset tulip chip */

        bus_space_write_1(iot, ioh, TUL_SCTRL0, RSCSI);

        do
                sc->HCS_JSInt = bus_space_read_1(iot, ioh, TUL_SISTAT);
        while((sc->HCS_JSInt & SRSTD) == 0);

        iha_set_ssig(iot, ioh, 0, 0);

        /*
         * Stall for 2 seconds, wait for target's firmware ready.
         */
        for (i = 0; i < 2000; i++)
                DELAY (1000);

        bus_space_read_1(iot, ioh, TUL_SISTAT); /* Clear any active interrupt*/
}

void
iha_select(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh,
    struct iha_scb *pScb, u_int8_t select_type)
{
        int s;

        switch (select_type) {
        case SEL_ATN:
                bus_space_write_1(iot, ioh, TUL_SFIFO, pScb->SCB_Ident);
                bus_space_write_multi_1(iot, ioh, TUL_SFIFO,
                    pScb->SCB_CDB, pScb->SCB_CDBLen);

                pScb->SCB_NxtStat = 2;
                break;

        case SELATNSTOP:
                pScb->SCB_NxtStat = 1;
                break;

        case SEL_ATN3:
                bus_space_write_1(iot, ioh, TUL_SFIFO, pScb->SCB_Ident);
                bus_space_write_1(iot, ioh, TUL_SFIFO, pScb->SCB_TagMsg);
                bus_space_write_1(iot, ioh, TUL_SFIFO, pScb->SCB_TagId);

                bus_space_write_multi_1(iot, ioh, TUL_SFIFO, pScb->SCB_CDB,
                    pScb->SCB_CDBLen);

                pScb->SCB_NxtStat = 2;
                break;

        default:
#ifdef IHA_DEBUG_STATE
                sc_print_addr(pScb->SCB_Xs->sc_link);
                printf("[debug] iha_select() - unknown select type = 0x%02x\n",
                    select_type);
#endif
                return;
        }

        s = splbio();
        TAILQ_REMOVE(&sc->HCS_PendScb, pScb, SCB_ScbList);
        splx(s);

        pScb->SCB_Status = STATUS_SELECT;

        sc->HCS_ActScb = pScb;

        bus_space_write_1(iot, ioh, TUL_SCMD, select_type);
}

/*
 * iha_wait - wait for an interrupt to service or a SCSI bus phase change
 *            after writing the supplied command to the tulip chip. If
 *            the command is NO_OP, skip the command writing.
 */
int
iha_wait(struct iha_softc *sc, bus_space_tag_t iot, bus_space_handle_t ioh,
    u_int8_t cmd)
{
        if (cmd != NO_OP)
                bus_space_write_1(iot, ioh, TUL_SCMD, cmd);

        /*
         * Have to do this here, in addition to in iha_isr, because
         * interrupts might be turned off when we get here.
         */
        do
                sc->HCS_JSStatus0 = bus_space_read_1(iot, ioh, TUL_STAT0);
        while ((sc->HCS_JSStatus0 & INTPD) == 0);

        sc->HCS_JSStatus1 = bus_space_read_1(iot, ioh, TUL_STAT1);
        sc->HCS_JSInt     = bus_space_read_1(iot, ioh, TUL_SISTAT);

        sc->HCS_Phase = sc->HCS_JSStatus0 & PH_MASK;

        if ((sc->HCS_JSInt & SRSTD) != 0) {
                /* SCSI bus reset interrupt */
                iha_reset_scsi_bus(sc);
                return (-1);
        }

        if ((sc->HCS_JSInt & RSELED) != 0)
                /* Reselection interrupt */
                return (iha_resel(sc, iot, ioh));

        if ((sc->HCS_JSInt & STIMEO) != 0) {
                /* selected/reselected timeout interrupt */
                iha_busfree(sc, iot, ioh);
                return (-1);
        }

        if ((sc->HCS_JSInt & DISCD) != 0) {
                /* BUS disconnection interrupt */
                if ((sc->HCS_Flags & FLAG_EXPECT_DONE_DISC) != 0) {
                        bus_space_write_1(iot, ioh, TUL_SCTRL0,   RSFIFO);
                        bus_space_write_1(iot, ioh, TUL_SCONFIG0,
                            SCONFIG0DEFAULT);
                        bus_space_write_1(iot, ioh, TUL_SCTRL1,   EHRSL);
                        iha_append_done_scb(sc, sc->HCS_ActScb, HOST_OK);
                        sc->HCS_Flags &= ~FLAG_EXPECT_DONE_DISC;

                } else if ((sc->HCS_Flags & FLAG_EXPECT_DISC) != 0) {
                        bus_space_write_1(iot, ioh, TUL_SCTRL0,   RSFIFO);
                        bus_space_write_1(iot, ioh, TUL_SCONFIG0,
                            SCONFIG0DEFAULT);
                        bus_space_write_1(iot, ioh, TUL_SCTRL1,   EHRSL);
                        sc->HCS_ActScb = NULL;
                        sc->HCS_Flags &= ~FLAG_EXPECT_DISC;

                } else
                        iha_busfree(sc, iot, ioh);

                return (-1);
        }

        return (sc->HCS_Phase);
}

/*
 * iha_done_scb - We have a scb which has been processed by the
 *                adaptor, now we look to see how the operation went.
 */
void
iha_done_scb(struct iha_softc *sc, struct iha_scb *pScb)
{
        struct scsi_sense_data *s1, *s2;
        struct scsi_xfer *xs = pScb->SCB_Xs;

        if (xs != NULL) {
                timeout_del(&xs->stimeout);

                xs->status = pScb->SCB_TaStat;

                if ((pScb->SCB_Flags & (SCSI_DATA_IN | SCSI_DATA_OUT)) != 0) {
                        bus_dmamap_sync(sc->sc_dmat, pScb->SCB_DataDma,
                                0, pScb->SCB_BufChars,
                                ((pScb->SCB_Flags & SCSI_DATA_IN) ?
                            BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE));
                        bus_dmamap_unload(sc->sc_dmat, pScb->SCB_DataDma);
                }
                if ((pScb->SCB_Flags & FLAG_SG) != 0) {
                        bus_dmamap_sync(sc->sc_dmat, pScb->SCB_SGDma,
                                0, sizeof(pScb->SCB_SGList),
                                BUS_DMASYNC_POSTWRITE);
                        bus_dmamap_unload(sc->sc_dmat, pScb->SCB_SGDma);
                }

                switch (pScb->SCB_HaStat) {
                case HOST_OK:
                        switch (pScb->SCB_TaStat) {
                        case SCSI_OK:
                        case SCSI_COND_MET:
                        case SCSI_INTERM:
                        case SCSI_INTERM_COND_MET:
                                xs->resid = pScb->SCB_BufCharsLeft;
                                xs->error = XS_NOERROR;
                                break;

                        case SCSI_RESV_CONFLICT:
                        case SCSI_BUSY:
                        case SCSI_QUEUE_FULL:
                                xs->error = XS_BUSY;
                                break;

                        case SCSI_TERMINATED:
                        case SCSI_ACA_ACTIVE:
                        case SCSI_CHECK:
                                s1 = &pScb->SCB_ScsiSenseData;
                                s2 = &xs->sense;
                                *s2 = *s1;

                                xs->error = XS_SENSE;
                                break;

                        default:
                                xs->error = XS_DRIVER_STUFFUP;
                                break;
                        }
                        break;

                case HOST_SEL_TOUT:
                        xs->error = XS_SELTIMEOUT;
                        break;

                case HOST_SCSI_RST:
                case HOST_DEV_RST:
                        xs->error = XS_RESET;
                        break;

                case HOST_SPERR:
                        sc_print_addr(xs->sc_link);
                        printf("SCSI Parity error detected\n");
                        xs->error = XS_DRIVER_STUFFUP;
                        break;

                case HOST_TIMED_OUT:
                        xs->error = XS_TIMEOUT;
                        break;

                case HOST_DO_DU:
                case HOST_BAD_PHAS:
                default:
                        xs->error = XS_DRIVER_STUFFUP;
                        break;
                }
                scsi_done(xs);
        }
}

void
iha_timeout(void *arg)
{
        struct iha_scb *pScb = (struct iha_scb *)arg;
        struct scsi_xfer *xs = pScb->SCB_Xs;

        if (xs != NULL) {
                sc_print_addr(xs->sc_link);
                printf("SCSI OpCode 0x%02x timed out\n", xs->cmd.opcode);
                iha_abort_xs(xs->sc_link->bus->sb_adapter_softc, xs, HOST_TIMED_OUT);
        }
}

void
iha_exec_scb(struct iha_softc *sc, struct iha_scb *pScb)
{
        struct scsi_xfer *xs = pScb->SCB_Xs;
        bus_space_handle_t ioh;
        bus_space_tag_t iot;
        int s;

        s = splbio();

        if ((pScb->SCB_Flags & SCSI_POLL) == 0)
                timeout_add_msec(&xs->stimeout, xs->timeout);

        if (((pScb->SCB_Flags & SCSI_RESET) != 0)
            || (pScb->SCB_CDB[0] == REQUEST_SENSE))
                iha_push_pend_scb(sc, pScb);   /* Insert SCB at head of Pend */
        else
                iha_append_pend_scb(sc, pScb); /* Append SCB to tail of Pend */

        /*
         * Run through iha_main() to ensure something is active, if
         * only this new SCB.
         */
        if (sc->HCS_Semaph != SEMAPH_IN_MAIN) {
                iot = sc->sc_iot;
                ioh = sc->sc_ioh;

                bus_space_write_1(iot, ioh, TUL_IMSK, MASK_ALL);
                sc->HCS_Semaph = SEMAPH_IN_MAIN;

                splx(s);
                iha_main(sc, iot, ioh);
                s = splbio();

                sc->HCS_Semaph = ~SEMAPH_IN_MAIN;
                bus_space_write_1(iot, ioh, TUL_IMSK, (MASK_ALL & ~MSCMP));
        }

        splx(s);
}


/*
 * iha_set_ssig - read the current scsi signal mask, then write a new
 *                one which turns off/on the specified signals.
 */
void
iha_set_ssig(bus_space_tag_t iot, bus_space_handle_t ioh, u_int8_t offsigs,
    u_int8_t onsigs)
{
        u_int8_t currsigs;

        currsigs = bus_space_read_1(iot, ioh, TUL_SSIGI);
        bus_space_write_1(iot, ioh, TUL_SSIGO, (currsigs & ~offsigs) | onsigs);
}

void
iha_print_info(struct iha_softc *sc, int target)
{
        u_int8_t period = sc->HCS_Tcs[target].TCS_JS_Period;
        u_int8_t config = sc->HCS_Tcs[target].TCS_SConfig0;
        int rate;

        printf("%s: target %d using %d bit ", sc->sc_dev.dv_xname, target,
                (period & PERIOD_WIDE_SCSI) ? 16 : 8);

        if ((period & PERIOD_SYOFS) == 0)
                printf("async ");
        else {
                rate = (period & PERIOD_SYXPD) >> 4;
                if ((config & ALTPD) == 0)
                        rate = 100 + rate * 50;
                else
                        rate =  50 + rate * 25;
                rate = 1000000000 / rate;
                printf("%d.%d MHz %d REQ/ACK offset ", rate / 1000000,
                    (rate % 1000000 + 99999) / 100000, period & PERIOD_SYOFS);
        }

        printf("xfers\n");
}


/*
 * iha_alloc_scbs - allocate and map the SCB's for the supplied iha_softc
 */
int
iha_alloc_scbs(struct iha_softc *sc)
{
        bus_dma_segment_t seg;
        int error, rseg;

        /*
         * Allocate dma-safe memory for the SCB's
         */
        if ((error = bus_dmamem_alloc(sc->sc_dmat,
                 sizeof(struct iha_scb)*IHA_MAX_SCB,
                 NBPG, 0, &seg, 1, &rseg, BUS_DMA_NOWAIT | BUS_DMA_ZERO))
            != 0) {
                printf("%s: unable to allocate SCBs,"
                       " error = %d\n", sc->sc_dev.dv_xname, error);
                return (error);
        }
        if ((error = bus_dmamem_map(sc->sc_dmat,
                 &seg, rseg, sizeof(struct iha_scb)*IHA_MAX_SCB,
                 (caddr_t *)&sc->HCS_Scb, BUS_DMA_NOWAIT | BUS_DMA_COHERENT))
            != 0) {
                printf("%s: unable to map SCBs, error = %d\n",
                       sc->sc_dev.dv_xname, error);
                return (error);
        }

        return (0);
}

/*
 * iha_read_eeprom - read contents of serial EEPROM into iha_nvram pointed at
 *                                        by parameter nvram.
 */
void
iha_read_eeprom(bus_space_tag_t iot, bus_space_handle_t ioh,
    struct iha_nvram *nvram)
{
        u_int32_t chksum;
        u_int16_t *np;
        u_int8_t gctrl, addr;

        const int chksum_addr = offsetof(struct iha_nvram, NVM_CheckSum) / 2;

        /* Enable EEProm programming */
        gctrl = bus_space_read_1(iot, ioh, TUL_GCTRL0) | EEPRG;
        bus_space_write_1(iot, ioh, TUL_GCTRL0, gctrl);

        /* Read EEProm */
        np = (u_int16_t *)nvram;
        for (addr=0, chksum=0; addr < chksum_addr; addr++, np++) {
                *np = iha_se2_rd(iot, ioh, addr);
                chksum += *np;
        }

        chksum &= 0x0000ffff;
        nvram->NVM_CheckSum = iha_se2_rd(iot, ioh, chksum_addr);

        /* Disable EEProm programming */
        gctrl = bus_space_read_1(iot, ioh, TUL_GCTRL0) & ~EEPRG;
        bus_space_write_1(iot, ioh, TUL_GCTRL0, gctrl);

        if ((nvram->NVM_Signature != SIGNATURE)
            ||
            (nvram->NVM_CheckSum  != chksum))
                panic("iha: invalid EEPROM,  bad signature or checksum");
}

/*
 * iha_se2_rd - read & return the 16 bit value at the specified
 *              offset in the Serial E2PROM
 *
 */
u_int16_t
iha_se2_rd(bus_space_tag_t iot, bus_space_handle_t ioh, u_int8_t addr)
{
        u_int16_t readWord;
        u_int8_t bit;
        int i;

        /* Send 'READ' instruction == address | READ bit */
        iha_se2_instr(iot, ioh, (addr | NVREAD));

        readWord = 0;
        for (i = 15; i >= 0; i--) {
                bus_space_write_1(iot, ioh, TUL_NVRAM, NVRCS | NVRCK);
                DELAY(5);

                bus_space_write_1(iot, ioh, TUL_NVRAM, NVRCS);
                DELAY(5);

                /* sample data after the following edge of clock     */
                bit = bus_space_read_1(iot, ioh, TUL_NVRAM) & NVRDI;
                DELAY(5);

                readWord += bit << i;
        }

        bus_space_write_1(iot, ioh, TUL_NVRAM, 0);
        DELAY(5);

        return (readWord);
}

/*
 * iha_se2_instr - write an octet to serial E2PROM one bit at a time
 */
void
iha_se2_instr(bus_space_tag_t iot, bus_space_handle_t ioh, u_int8_t instr)
{
        u_int8_t b;
        int i;

        b = NVRCS | NVRDO; /* Write the start bit (== 1) */

        bus_space_write_1(iot, ioh, TUL_NVRAM, b);
        DELAY(5);
        bus_space_write_1(iot, ioh, TUL_NVRAM, b | NVRCK);
        DELAY(5);

        for (i = 0; i < 8; i++, instr <<= 1) {
                if (instr & 0x80)
                        b = NVRCS | NVRDO; /* Write a 1 bit */
                else
                        b = NVRCS;         /* Write a 0 bit */

                bus_space_write_1(iot, ioh, TUL_NVRAM, b);
                DELAY(5);
                bus_space_write_1(iot, ioh, TUL_NVRAM, b | NVRCK);
                DELAY(5);
        }

        bus_space_write_1(iot, ioh, TUL_NVRAM, NVRCS);
        DELAY(5);

        return;
}

/*
 * iha_reset_tcs - reset the target control structure pointed
 *                 to by pTcs to default values. TCS_Flags
 *                 only has the negotiation done bits reset as
 *                 the other bits are fixed at initialization.
 */
void
iha_reset_tcs(struct tcs *pTcs, u_int8_t config0)
{
        pTcs->TCS_Flags     &= ~(FLAG_SYNC_DONE | FLAG_WIDE_DONE);
        pTcs->TCS_JS_Period  = 0;
        pTcs->TCS_SConfig0   = config0;
        pTcs->TCS_TagCnt     = 0;
        pTcs->TCS_NonTagScb  = NULL;
}