xref: /src/sys/dev/ic/siop.c

/*	$NetBSD: siop.c,v 1.31 2000/10/18 17:06:52 bouyer Exp $	*/

/*
 * Copyright (c) 2000 Manuel Bouyer.
 *
 * 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 Manuel Bouyer
 * 4. 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.
 *
 */

/* SYM53c7/8xx PCI-SCSI I/O Processors driver */

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

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

#include <dev/microcode/siop/siop.out>

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

#include <dev/scsipi/scsiconf.h>

#include <dev/ic/siopreg.h>
#include <dev/ic/siopvar.h>
#include <dev/ic/siopvar_common.h>

#undef DEBUG
#undef DEBUG_DR
#undef DEBUG_INTR
#undef DEBUG_SCHED
#undef DUMP_SCRIPT

#define SIOP_STATS

#ifndef SIOP_DEFAULT_TARGET
#define SIOP_DEFAULT_TARGET 7
#endif

/* number of cmd descriptors per block */
#define SIOP_NCMDPB (NBPG / sizeof(struct siop_xfer))

void	siop_reset __P((struct siop_softc *));
void	siop_handle_reset __P((struct siop_softc *));
int	siop_handle_qtag_reject __P((struct siop_cmd *));
void	siop_scsicmd_end __P((struct siop_cmd *));
void	siop_start __P((struct siop_softc *));
void 	siop_timeout __P((void *));
int	siop_scsicmd __P((struct scsipi_xfer *));
void	siop_dump_script __P((struct siop_softc *));
int	siop_morecbd __P((struct siop_softc *));
struct siop_lunsw *siop_get_lunsw __P((struct siop_softc *));
void	siop_add_reselsw __P((struct siop_softc *, int));
void	siop_update_scntl3 __P((struct siop_softc *, struct siop_target *));

struct scsipi_adapter siop_adapter = {
	0,
	siop_scsicmd,
	siop_minphys,
	siop_ioctl,
	NULL,
	NULL,
};

struct scsipi_device siop_dev = {
	NULL,
	NULL,
	NULL,
	NULL,
};

#ifdef SIOP_STATS
static int siop_stat_intr = 0;
static int siop_stat_intr_shortxfer = 0;
static int siop_stat_intr_sdp = 0;
static int siop_stat_intr_done = 0;
static int siop_stat_intr_xferdisc = 0;
void siop_printstats __P((void));
#define INCSTAT(x) x++
#else
#define INCSTAT(x)
#endif

static __inline__ void siop_table_sync __P((struct siop_cmd *, int));
static __inline__ void
siop_table_sync(siop_cmd, ops)
	struct siop_cmd *siop_cmd;
	int ops;
{
	struct siop_softc *sc  = siop_cmd->siop_sc;
	bus_addr_t offset;

	offset = siop_cmd->dsa -
	    siop_cmd->siop_cbdp->xferdma->dm_segs[0].ds_addr;
	bus_dmamap_sync(sc->sc_dmat, siop_cmd->siop_cbdp->xferdma, offset,
	    sizeof(struct siop_xfer), ops);
}

static __inline__ void siop_sched_sync __P((struct siop_softc *, int));
static __inline__ void
siop_sched_sync(sc, ops)
	struct siop_softc *sc;
	int ops;
{
	bus_dmamap_sync(sc->sc_dmat, sc->sc_scheddma, 0, NBPG, ops);
}

static __inline__ u_int32_t siop_script_read __P((struct siop_softc *, int));
static __inline__ u_int32_t
siop_script_read(sc, offset)
	struct siop_softc *sc;
	int offset;
{
	if (sc->features & SF_CHIP_RAM) {
		return bus_space_read_4(sc->sc_ramt, sc->sc_ramh, offset * 4);
	} else {
		return le32toh(sc->sc_script[offset]);
	}
}

static __inline__ void siop_script_write __P((struct siop_softc *, int,
	u_int32_t));
static __inline__ void
siop_script_write(sc, offset, val)
	struct siop_softc *sc;
	int offset;
	u_int32_t val;
{
	if (sc->features & SF_CHIP_RAM) {
		bus_space_write_4(sc->sc_ramt, sc->sc_ramh, offset * 4, val);
	} else {
		sc->sc_script[offset] = htole32(val);
	}
}


void
siop_attach(sc)
	struct siop_softc *sc;
{
	int error, i;
	bus_dma_segment_t seg;
	int rseg;

	/*
	 * Allocate DMA-safe memory for the script and script scheduler
	 * and map it.
	 */
	if ((sc->features & SF_CHIP_RAM) == 0) {
		error = bus_dmamem_alloc(sc->sc_dmat, NBPG,
		    NBPG, 0, &seg, 1, &rseg, BUS_DMA_NOWAIT);
		if (error) {
			printf("%s: unable to allocate script DMA memory, "
			    "error = %d\n", sc->sc_dev.dv_xname, error);
			return;
		}
		error = bus_dmamem_map(sc->sc_dmat, &seg, rseg, NBPG,
		    (caddr_t *)&sc->sc_script, BUS_DMA_NOWAIT|BUS_DMA_COHERENT);
		if (error) {
			printf("%s: unable to map script DMA memory, "
			    "error = %d\n", sc->sc_dev.dv_xname, error);
			return;
		}
		error = bus_dmamap_create(sc->sc_dmat, NBPG, 1,
		    NBPG, 0, BUS_DMA_NOWAIT, &sc->sc_scriptdma);
		if (error) {
			printf("%s: unable to create script DMA map, "
			    "error = %d\n", sc->sc_dev.dv_xname, error);
			return;
		}
		error = bus_dmamap_load(sc->sc_dmat, sc->sc_scriptdma,
		    sc->sc_script, NBPG, NULL, BUS_DMA_NOWAIT);
		if (error) {
			printf("%s: unable to load script DMA map, "
			    "error = %d\n", sc->sc_dev.dv_xname, error);
			return;
		}
		sc->sc_scriptaddr = sc->sc_scriptdma->dm_segs[0].ds_addr;
	}
	error = bus_dmamem_alloc(sc->sc_dmat, NBPG,
	    NBPG, 0, &seg, 1, &rseg, BUS_DMA_NOWAIT);
	if (error) {
		printf("%s: unable to allocate scheduler DMA memory, "
		    "error = %d\n", sc->sc_dev.dv_xname, error);
		return;
	}
	error = bus_dmamem_map(sc->sc_dmat, &seg, rseg, NBPG,
	    (caddr_t *)&sc->sc_sched, BUS_DMA_NOWAIT|BUS_DMA_COHERENT);
	if (error) {
		printf("%s: unable to map scheduler DMA memory, error = %d\n",
		    sc->sc_dev.dv_xname, error);
		return;
	}
	error = bus_dmamap_create(sc->sc_dmat, NBPG, 1,
	    NBPG, 0, BUS_DMA_NOWAIT, &sc->sc_scheddma);
	if (error) {
		printf("%s: unable to create scheduler DMA map, error = %d\n",
		    sc->sc_dev.dv_xname, error);
		return;
	}
	error = bus_dmamap_load(sc->sc_dmat, sc->sc_scheddma, sc->sc_sched,
	    NBPG, NULL, BUS_DMA_NOWAIT);
	if (error) {
		printf("%s: unable to load scheduler DMA map, error = %d\n",
		    sc->sc_dev.dv_xname, error);
		return;
	}
	TAILQ_INIT(&sc->free_list);
	TAILQ_INIT(&sc->ready_list);
	TAILQ_INIT(&sc->cmds);
	TAILQ_INIT(&sc->lunsw_list);
	/* compute number of scheduler slots */
	sc->sc_nschedslots = (
	    NBPG /* memory size allocated for scheduler */
	    - sizeof(endslot_script) /* memory needed at end of scheduler */
	    ) / (sizeof(slot_script) - 8);
	sc->sc_currschedslot = 0;
#ifdef DEBUG
	printf("%s: script size = %d, PHY addr=0x%x, VIRT=%p nslots %d\n",
	    sc->sc_dev.dv_xname, (int)sizeof(siop_script),
	    (u_int32_t)sc->sc_scriptaddr, sc->sc_script, sc->sc_nschedslots);
#endif

	sc->sc_link.adapter_softc = sc;
	sc->sc_link.openings = 1;
	sc->sc_link.scsipi_scsi.channel = SCSI_CHANNEL_ONLY_ONE;
	sc->sc_link.scsipi_scsi.max_target  =
	    (sc->features & SF_BUS_WIDE) ? 15 : 7;
	sc->sc_link.scsipi_scsi.max_lun = 7;
	sc->sc_link.scsipi_scsi.adapter_target = bus_space_read_1(sc->sc_rt,
	    sc->sc_rh, SIOP_SCID);
	if (sc->sc_link.scsipi_scsi.adapter_target == 0 ||
	    sc->sc_link.scsipi_scsi.adapter_target >
	    sc->sc_link.scsipi_scsi.max_target)
		sc->sc_link.scsipi_scsi.adapter_target = SIOP_DEFAULT_TARGET;
	sc->sc_link.type = BUS_SCSI;
	sc->sc_link.adapter = &siop_adapter;
	sc->sc_link.device = &siop_dev;
	sc->sc_link.flags  = 0;

	for (i = 0; i < 16; i++)
		sc->targets[i] = NULL;

	/* find min/max sync period for this chip */
	sc->maxsync = 0;
	sc->minsync = 255;
	for (i = 0; i < sizeof(scf_period) / sizeof(scf_period[0]); i++) {
		if (sc->clock_period != scf_period[i].clock)
			continue;
		if (sc->maxsync < scf_period[i].period)
			sc->maxsync = scf_period[i].period;
		if (sc->minsync > scf_period[i].period)
			sc->minsync = scf_period[i].period;
	}
	if (sc->maxsync == 255 || sc->minsync == 0)
		panic("siop: can't find my sync parameters\n");
	/* Do a bus reset, so that devices fall back to narrow/async */
	siop_resetbus(sc);
	/*
	 * siop_reset() will reset the chip, thus clearing pending interrupts
	 */
	siop_reset(sc);
#ifdef DUMP_SCRIPT
	siop_dump_script(sc);
#endif

	config_found((struct device*)sc, &sc->sc_link, scsiprint);
}

void
siop_reset(sc)
	struct siop_softc *sc;
{
	int i, j;
	u_int32_t *scr;
	bus_addr_t physaddr;
	struct siop_lunsw *lunsw;

	siop_common_reset(sc);

	/* copy and patch the script */
	if (sc->features & SF_CHIP_RAM) {
		bus_space_write_region_4(sc->sc_ramt, sc->sc_ramh, 0,
		    siop_script, sizeof(siop_script) / sizeof(siop_script[0]));
		for (j = 0; j <
		    (sizeof(E_script_abs_sched_Used) /
		    sizeof(E_script_abs_sched_Used[0]));
		    j++) {
			bus_space_write_4(sc->sc_ramt, sc->sc_ramh,
			    E_script_abs_sched_Used[j] * 4,
			    sc->sc_scheddma->dm_segs[0].ds_addr);
		}
		for (j = 0; j <
		    (sizeof(E_abs_msgin_Used) / sizeof(E_abs_msgin_Used[0]));
		    j++) {
			bus_space_write_4(sc->sc_ramt, sc->sc_ramh,
			    E_abs_msgin_Used[j] * 4,
			    sc->sc_scriptaddr + Ent_msgin_space);
		}
	} else {
		for (j = 0;
		    j < (sizeof(siop_script) / sizeof(siop_script[0])); j++) {
			sc->sc_script[j] = htole32(siop_script[j]);
		}
		for (j = 0; j <
		    (sizeof(E_script_abs_sched_Used) /
		    sizeof(E_script_abs_sched_Used[0]));
		    j++) {
			sc->sc_script[E_script_abs_sched_Used[j]] =
			    htole32(sc->sc_scheddma->dm_segs[0].ds_addr);
		}
		for (j = 0; j <
		    (sizeof(E_abs_msgin_Used) / sizeof(E_abs_msgin_Used[0]));
		    j++) {
			sc->sc_script[E_abs_msgin_Used[j]] =
			    htole32(sc->sc_scriptaddr + Ent_msgin_space);
		}
	}
	sc->ram_free = sizeof(siop_script) / sizeof(siop_script[0]);
	/* copy and init the scheduler slots script */
	for (i = 0; i < sc->sc_nschedslots; i++) {
		scr = &sc->sc_sched[(Ent_nextslot / 4) * i];
		physaddr = sc->sc_scheddma->dm_segs[0].ds_addr +
		    Ent_nextslot * i;
		for (j = 0; j < (Ent_nextslot / 4); j++) {
			scr[j] = htole32(slot_script[j]);
		}
		/*
		 * save current jump offset and patch MOVE MEMORY operands
		 * to restore it.
		 */
		scr[(Ent_slotdata/4) + 1] = scr[(Ent_slot/4) + 1];
		scr[E_slot_nextp_Used[0]] = htole32(physaddr + Ent_slot + 4);
		scr[E_slot_sched_addrsrc_Used[0]] = htole32(physaddr +
		    Ent_slotdata + 4);
		/* JUMP selected, in main script */
		scr[E_slot_abs_selected_Used[0]] =
		   htole32(sc->sc_scriptaddr + Ent_selected);
		/* JUMP addr if SELECT fail */
		scr[E_slot_abs_reselect_Used[0]] =
		   htole32(sc->sc_scriptaddr + Ent_reselect);
	}
	/* Now the final JUMP */
	scr = &sc->sc_sched[(Ent_nextslot / 4) * sc->sc_nschedslots];
	for (j = 0; j < (sizeof(endslot_script) / sizeof(endslot_script[0]));
	    j++) {
		scr[j] = htole32(endslot_script[j]);
	}
	scr[E_endslot_abs_reselect_Used[0]] =
	    htole32(sc->sc_scriptaddr + Ent_reselect);

	/* free used and unused lun switches */
	while((lunsw = TAILQ_FIRST(&sc->lunsw_list)) != NULL) {
#ifdef DEBUG
		printf("%s: free lunsw at offset %d\n",
				sc->sc_dev.dv_xname, lunsw->lunsw_off);
#endif
		TAILQ_REMOVE(&sc->lunsw_list, lunsw, next);
		free(lunsw, M_DEVBUF);
	}
	TAILQ_INIT(&sc->lunsw_list);
	/* restore reselect switch */
	for (i = 0; i < sc->sc_link.scsipi_scsi.max_target; i++) {
		if (sc->targets[i] == NULL)
			continue;
#ifdef DEBUG
		printf("%s: restore sw for target %d\n",
				sc->sc_dev.dv_xname, i);
#endif
		free(sc->targets[i]->lunsw, M_DEVBUF);
		sc->targets[i]->lunsw = siop_get_lunsw(sc);
		if (sc->targets[i]->lunsw == NULL) {
			printf("%s: can't alloc lunsw for target %d\n",
			    sc->sc_dev.dv_xname, i);
			break;
		}
		siop_add_reselsw(sc, i);
	}

	/* start script */
	if ((sc->features & SF_CHIP_RAM) == 0) {
		bus_dmamap_sync(sc->sc_dmat, sc->sc_scriptdma, 0, NBPG,
		    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
	}
	siop_sched_sync(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
	bus_space_write_4(sc->sc_rt, sc->sc_rh, SIOP_DSP,
	    sc->sc_scriptaddr + Ent_reselect);
}

#if 0
#define CALL_SCRIPT(ent) do {\
	printf ("start script DSA 0x%lx DSP 0x%lx\n", \
	    siop_cmd->dsa, \
	    sc->sc_scriptaddr + ent); \
bus_space_write_4(sc->sc_rt, sc->sc_rh, SIOP_DSP, sc->sc_scriptaddr + ent); \
} while (0)
#else
#define CALL_SCRIPT(ent) do {\
bus_space_write_4(sc->sc_rt, sc->sc_rh, SIOP_DSP, sc->sc_scriptaddr + ent); \
} while (0)
#endif

int
siop_intr(v)
	void *v;
{
	struct siop_softc *sc = v;
	struct siop_target *siop_target;
	struct siop_cmd *siop_cmd;
	struct siop_lun *siop_lun;
	struct scsipi_xfer *xs;
	int istat, sist0, sist1, sstat1, dstat;
	u_int32_t irqcode;
	int need_reset = 0;
	int freetarget = 0;
	int offset, lun;
	bus_addr_t dsa;
	struct siop_cbd *cbdp;

	istat = bus_space_read_1(sc->sc_rt, sc->sc_rh, SIOP_ISTAT);
	if ((istat & (ISTAT_INTF | ISTAT_DIP | ISTAT_SIP)) == 0)
		return 0;
	INCSTAT(siop_stat_intr);
	if (istat & ISTAT_INTF) {
		printf("INTRF\n");
		bus_space_write_1(sc->sc_rt, sc->sc_rh, SIOP_ISTAT, ISTAT_INTF);
	}
	/* use DSA to find the current siop_cmd */
	dsa = bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSA);
	for (cbdp = TAILQ_FIRST(&sc->cmds); cbdp != NULL;
	    cbdp = TAILQ_NEXT(cbdp, next)) {
		if (dsa >= cbdp->xferdma->dm_segs[0].ds_addr &&
	    	    dsa < cbdp->xferdma->dm_segs[0].ds_addr + NBPG) {
			dsa -= cbdp->xferdma->dm_segs[0].ds_addr;
			siop_cmd = &cbdp->cmds[dsa / sizeof(struct siop_xfer)];
			siop_table_sync(siop_cmd,
			    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
			break;
		}
	}
	if (cbdp == NULL) {
		siop_cmd = NULL;
	}
	if (siop_cmd) {
		xs = siop_cmd->xs;
		siop_target = siop_cmd->siop_target;
		lun = siop_cmd->xs->sc_link->scsipi_scsi.lun;
		siop_lun = &(siop_target->siop_lun[lun]);
#ifdef DIAGNOSTIC
		if (siop_cmd->status != CMDST_ACTIVE &&
		    siop_cmd->status != CMDST_SENSE_ACTIVE) {
			printf("siop_cmd (lun %d) not active (%d)\n",
				lun, siop_cmd->status);
			xs = NULL;
			siop_target = NULL;
			lun = -1;
			siop_lun = NULL;
			siop_cmd = NULL;
		} else if (siop_lun->active != siop_cmd) {
			printf("siop_cmd (lun %d) not in siop_lun active "
			    "(%p != %p)\n", lun, siop_cmd, siop_lun->active);
		}
#endif
	} else {
		xs = NULL;
		siop_target = NULL;
		lun = -1;
		siop_lun = NULL;
	}
	if (istat & ISTAT_DIP) {
		u_int32_t *p;
		dstat = bus_space_read_1(sc->sc_rt, sc->sc_rh, SIOP_DSTAT);
		if (dstat & DSTAT_SSI) {
			printf("single step dsp 0x%08x dsa 0x08%x\n",
			    (int)(bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSP) -
			    sc->sc_scriptaddr),
			    bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSA));
			if ((dstat & ~(DSTAT_DFE | DSTAT_SSI)) == 0 &&
			    (istat & ISTAT_SIP) == 0) {
				bus_space_write_1(sc->sc_rt, sc->sc_rh,
				    SIOP_DCNTL, bus_space_read_1(sc->sc_rt,
				    sc->sc_rh, SIOP_DCNTL) | DCNTL_STD);
			}
			return 1;
		}
		if (dstat & ~(DSTAT_SIR | DSTAT_DFE | DSTAT_SSI)) {
		printf("DMA IRQ:");
		if (dstat & DSTAT_IID)
			printf(" Illegal instruction");
		if (dstat & DSTAT_ABRT)
			printf(" abort");
		if (dstat & DSTAT_BF)
			printf(" bus fault");
		if (dstat & DSTAT_MDPE)
			printf(" parity");
		if (dstat & DSTAT_DFE)
			printf(" dma fifo empty");
		printf(", DSP=0x%x DSA=0x%x: ",
		    (int)(bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSP) -
		    sc->sc_scriptaddr),
		    bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSA));
		p = sc->sc_script +
		    (bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSP) -
		    sc->sc_scriptaddr - 8) / 4;
		printf("0x%x 0x%x 0x%x 0x%x\n", le32toh(p[0]), le32toh(p[1]),
		    le32toh(p[2]), le32toh(p[3]));
		if (siop_cmd)
			printf("last msg_in=0x%x status=0x%x\n",
			    siop_cmd->siop_tables.msg_in[0],
			    le32toh(siop_cmd->siop_tables.status));
		else
			printf("%s: current DSA invalid\n",
			    sc->sc_dev.dv_xname);
		need_reset = 1;
		}
	}
	if (istat & ISTAT_SIP) {
		if (istat & ISTAT_DIP)
			delay(10);
		sist0 = bus_space_read_1(sc->sc_rt, sc->sc_rh, SIOP_SIST0);
			delay(10);
		sist1 = bus_space_read_1(sc->sc_rt, sc->sc_rh, SIOP_SIST1);
		sstat1 = bus_space_read_1(sc->sc_rt, sc->sc_rh, SIOP_SSTAT1);
#ifdef DEBUG_INTR
		printf("scsi interrupt, sist0=0x%x sist1=0x%x sstat1=0x%x "
		    "DSA=0x%x DSP=0x%lx\n", sist0, sist1,
		    bus_space_read_1(sc->sc_rt, sc->sc_rh, SIOP_SSTAT1),
		    bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSA),
		    (u_long)(bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSP) -
		    sc->sc_scriptaddr));
#endif
		if (sist0 & SIST0_RST) {
			siop_handle_reset(sc);
			siop_start(sc);
			/* no table to flush here */
			return 1;
		}
		if (sist0 & SIST0_SGE) {
			if (siop_cmd)
				scsi_print_addr(xs->sc_link);
			else
				printf("%s:", sc->sc_dev.dv_xname);
			printf("scsi gross error\n");
			goto reset;
		}
		if ((sist0 & SIST0_MA) && need_reset == 0) {
			if (siop_cmd) {
				int scratcha0;
				dstat = bus_space_read_1(sc->sc_rt, sc->sc_rh,
				    SIOP_DSTAT);
				/*
				 * first restore DSA, in case we were in a S/G
				 * operation.
				 */
				bus_space_write_4(sc->sc_rt, sc->sc_rh,
				    SIOP_DSA, siop_cmd->dsa);
				scratcha0 = bus_space_read_1(sc->sc_rt,
				    sc->sc_rh, SIOP_SCRATCHA);
				switch (sstat1 & SSTAT1_PHASE_MASK) {
				case SSTAT1_PHASE_STATUS:
				/*
				 * previous phase may be aborted for any reason
				 * ( for example, the target has less data to
				 * transfer than requested). Just go to status
				 * and the command should terminate.
				 */
					INCSTAT(siop_stat_intr_shortxfer);
					if ((dstat & DSTAT_DFE) == 0)
						siop_clearfifo(sc);
					/* no table to flush here */
					CALL_SCRIPT(Ent_status);
					return 1;
				case SSTAT1_PHASE_MSGIN:
					/*
					 * target may be ready to disconnect
					 * Save data pointers just in case.
					 */
					INCSTAT(siop_stat_intr_xferdisc);
					if (scratcha0 & A_flag_data)
						siop_sdp(siop_cmd);
					else if ((dstat & DSTAT_DFE) == 0)
						siop_clearfifo(sc);
					bus_space_write_1(sc->sc_rt, sc->sc_rh,
					    SIOP_SCRATCHA,
					    scratcha0 & ~A_flag_data);
					siop_table_sync(siop_cmd,
					    BUS_DMASYNC_PREREAD |
					    BUS_DMASYNC_PREWRITE);
					CALL_SCRIPT(Ent_msgin);
					return 1;
				}
				printf("%s: unexpected phase mismatch %d\n",
				    sc->sc_dev.dv_xname,
				    sstat1 & SSTAT1_PHASE_MASK);
			} else {
				printf("%s: phase mismatch without command\n",
				    sc->sc_dev.dv_xname);
			}
			need_reset = 1;
		}
		if (sist0 & SIST0_PAR) {
			/* parity error, reset */
			if (siop_cmd)
				scsi_print_addr(xs->sc_link);
			else
				printf("%s:", sc->sc_dev.dv_xname);
			printf("parity error\n");
			goto reset;
		}
		if ((sist1 & SIST1_STO) && need_reset == 0) {
			/* selection time out, assume there's no device here */
			if (siop_cmd) {
				siop_cmd->status = CMDST_DONE;
				xs->error = XS_SELTIMEOUT;
				freetarget = 1;
				goto end;
			} else {
				printf("%s: selection timeout without "
				    "command\n", sc->sc_dev.dv_xname);
				need_reset = 1;
			}
		}
		if (sist0 & SIST0_UDC) {
			/*
			 * unexpected disconnect. Usually the target signals
			 * a fatal condition this way. Attempt to get sense.
			 */
			 if (siop_cmd)
				goto check_sense;
			printf("%s: unexpected disconnect without "
			    "command\n", sc->sc_dev.dv_xname);
			goto reset;
		}
		if (sist1 & SIST1_SBMC) {
			/* SCSI bus mode change */
			if (siop_modechange(sc) == 0 || need_reset == 1)
				goto reset;
			if ((istat & ISTAT_DIP) && (dstat & DSTAT_SIR)) {
				/*
				 * we have a script interrupt, it will
				 * restart the script.
				 */
				goto scintr;
			}
			/*
			 * else we have to restart it ourselve, at the
			 * interrupted instruction.
			 */
			bus_space_write_4(sc->sc_rt, sc->sc_rh, SIOP_DSP,
			    bus_space_read_4(sc->sc_rt, sc->sc_rh,
			    SIOP_DSP) - 8);
			return 1;
		}
		/* Else it's an unhandled exeption (for now). */
		printf("%s: unhandled scsi interrupt, sist0=0x%x sist1=0x%x "
		    "sstat1=0x%x DSA=0x%x DSP=0x%x\n", sc->sc_dev.dv_xname,
		    sist0, sist1,
		    bus_space_read_1(sc->sc_rt, sc->sc_rh, SIOP_SSTAT1),
		    bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSA),
		    (int)(bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSP) -
		    sc->sc_scriptaddr));
		if (siop_cmd) {
			siop_cmd->status = CMDST_DONE;
			xs->error = XS_SELTIMEOUT;
			goto end;
		}
		need_reset = 1;
	}
	if (need_reset) {
reset:
		/* fatal error, reset the bus */
		siop_resetbus(sc);
		/* no table to flush here */
		return 1;
	}

scintr:
	if ((istat & ISTAT_DIP) && (dstat & DSTAT_SIR)) { /* script interrupt */
		irqcode = bus_space_read_4(sc->sc_rt, sc->sc_rh,
		    SIOP_DSPS);
#ifdef DEBUG_INTR
		printf("script interrupt 0x%x\n", irqcode);
#endif
		/*
		 * no command, or an inactive command is only valid for a
		 * reselect interrupt
		 */
		if ((irqcode & 0x80) == 0) {
			if (siop_cmd == NULL) {
				printf("%s: script interrupt (0x%x) with
				    invalid DSA !!!\n", sc->sc_dev.dv_xname,
				    irqcode);
				goto reset;
			}
			if (siop_cmd->status != CMDST_ACTIVE &&
			    siop_cmd->status != CMDST_SENSE_ACTIVE) {
				printf("%s: command with invalid status "
				    "(IRQ code 0x%x current status %d) !\n",
				    sc->sc_dev.dv_xname,
				    irqcode, siop_cmd->status);
				xs = NULL;
			}
		}
		switch(irqcode) {
		case A_int_err:
			printf("error, DSP=0x%x\n",
			    (int)(bus_space_read_4(sc->sc_rt, sc->sc_rh,
			    SIOP_DSP) - sc->sc_scriptaddr));
			if (xs) {
				xs->error = XS_SELTIMEOUT;
				goto end;
			} else {
				goto reset;
			}
		case A_int_reseltarg:
			printf("%s: reselect with invalid target\n",
				    sc->sc_dev.dv_xname);
			goto reset;
		case A_int_resellun:
			printf("%s: reselect with invalid lun\n",
				    sc->sc_dev.dv_xname);
			goto reset;
		case A_int_reseltag:
			printf("%s: reselect with invalid tag\n",
				    sc->sc_dev.dv_xname);
			goto reset;
		case A_int_msgin:
		{
			int msgin = bus_space_read_1(sc->sc_rt, sc->sc_rh,
			    SIOP_SFBR);
			if (msgin == MSG_MESSAGE_REJECT) {
				int msg, extmsg;
				if (siop_cmd->siop_tables.msg_out[0] & 0x80) {
					/*
					 * message was part of a identify +
					 * something else. Identify shoudl't
					 * have been rejected.
					 */
					msg = siop_cmd->siop_tables.msg_out[1];
					extmsg =
					    siop_cmd->siop_tables.msg_out[3];
				} else {
					msg = siop_cmd->siop_tables.msg_out[0];
					extmsg =
					    siop_cmd->siop_tables.msg_out[2];
				}
				if (msg == MSG_MESSAGE_REJECT) {
					/* MSG_REJECT  for a MSG_REJECT  !*/
					if (xs)
						scsi_print_addr(xs->sc_link);
					else
						printf("%s: ",
						   sc->sc_dev.dv_xname);
					printf("our reject message was "
					    "rejected\n");
					goto reset;
				}
				if (msg == MSG_EXTENDED &&
				    extmsg == MSG_EXT_WDTR) {
					/* WDTR rejected, initiate sync */
					printf("%s: target %d using 8bit "
					    "transfers\n", sc->sc_dev.dv_xname,
					    xs->sc_link->scsipi_scsi.target);
					if ((siop_target->flags & TARF_SYNC)
					    == 0) {
						siop_target->status = TARST_OK;
						/* no table to flush here */
						CALL_SCRIPT(Ent_msgin_ack);
						return 1;
					}
					siop_target->status = TARST_SYNC_NEG;
					siop_cmd->siop_tables.msg_out[0] =
					    MSG_EXTENDED;
					siop_cmd->siop_tables.msg_out[1] =
					    MSG_EXT_SDTR_LEN;
					siop_cmd->siop_tables.msg_out[2] =
					    MSG_EXT_SDTR;
					siop_cmd->siop_tables.msg_out[3] =
					    sc->minsync;
					siop_cmd->siop_tables.msg_out[4] =
					    sc->maxoff;
					siop_cmd->siop_tables.t_msgout.count =
					    htole32(MSG_EXT_SDTR_LEN + 2);
					siop_cmd->siop_tables.t_msgout.addr =
					    htole32(siop_cmd->dsa);
					siop_table_sync(siop_cmd,
					    BUS_DMASYNC_PREREAD |
					    BUS_DMASYNC_PREWRITE);
					CALL_SCRIPT(Ent_send_msgout);
					return 1;
				} else if (msg == MSG_EXTENDED &&
				    extmsg == MSG_EXT_SDTR) {
					/* sync rejected */
					printf("%s: target %d asynchronous\n",
					    sc->sc_dev.dv_xname,
					    xs->sc_link->scsipi_scsi.target);
					siop_target->status = TARST_OK;
					/* no table to flush here */
					CALL_SCRIPT(Ent_msgin_ack);
					return 1;
				}
				if (xs)
					scsi_print_addr(xs->sc_link);
				else
					printf("%s: ", sc->sc_dev.dv_xname);
				if (msg == MSG_EXTENDED) {
					printf("scsi message reject, extended "
					    "message sent was 0x%x\n", extmsg);
				} else {
					printf("scsi message reject, message "
					    "sent was 0x%x\n", msg);
					if (msg == MSG_SIMPLE_Q_TAG ||
					    msg == MSG_HEAD_OF_Q_TAG ||
					    msg == MSG_ORDERED_Q_TAG)
						if (siop_handle_qtag_reject(
						    siop_cmd) == -1)
							goto reset;
				}
				/* no table to flush here */
				CALL_SCRIPT(Ent_msgin_ack);
				return 1;
			}
			if (xs)
				scsi_print_addr(xs->sc_link);
			else
				printf("%s: ", sc->sc_dev.dv_xname);
			printf("unhandled message 0x%x\n",
			    siop_cmd->siop_tables.msg_in[0]);
			siop_cmd->siop_tables.t_msgout.count= htole32(1);
			siop_cmd->siop_tables.t_msgout.addr =
			    htole32(siop_cmd->dsa);
			siop_cmd->siop_tables.msg_out[0] = MSG_MESSAGE_REJECT;
			siop_table_sync(siop_cmd,
			    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
			CALL_SCRIPT(Ent_send_msgout);
			return 1;
		}
		case A_int_extmsgin:
#ifdef DEBUG_INTR
			printf("extended message: msg 0x%x len %d\n",
			    siop_cmd->siop_tables.msg_in[2],
			    siop_cmd->siop_tables.msg_in[1]);
#endif
			if (siop_cmd->siop_tables.msg_in[1] > 6)
				printf("%s: extended message too big (%d)\n",
				    sc->sc_dev.dv_xname,
				    siop_cmd->siop_tables.msg_in[1]);
			siop_cmd->siop_tables.t_extmsgdata.count =
			    htole32(siop_cmd->siop_tables.msg_in[1] - 1);
			siop_cmd->siop_tables.t_extmsgdata.addr =
			    htole32(
			    le32toh(siop_cmd->siop_tables.t_extmsgin.addr)
			    + 2);
			siop_table_sync(siop_cmd,
			    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
			CALL_SCRIPT(Ent_get_extmsgdata);
			return 1;
		case A_int_extmsgdata:
#ifdef DEBUG_INTR
			{
			int i;
			printf("extended message: 0x%x, data:",
			    siop_cmd->siop_tables.msg_in[2]);
			for (i = 3; i < 2 + siop_cmd->siop_tables.msg_in[1];
			    i++)
				printf(" 0x%x",
				    siop_cmd->siop_tables.msg_in[i]);
			printf("\n");
			}
#endif
			if (siop_cmd->siop_tables.msg_in[2] == MSG_EXT_WDTR) {
				switch (siop_wdtr_neg(siop_cmd)) {
				case SIOP_NEG_MSGOUT:
					siop_update_scntl3(sc,
					    siop_cmd->siop_target);
					siop_table_sync(siop_cmd,
					    BUS_DMASYNC_PREREAD |
					    BUS_DMASYNC_PREWRITE);
					CALL_SCRIPT(Ent_send_msgout);
					return(1);
				case SIOP_NEG_ACK:
					siop_update_scntl3(sc,
					    siop_cmd->siop_target);
					CALL_SCRIPT(Ent_msgin_ack);
					return(1);
				default:
					panic("invalid retval from "
					    "siop_wdtr_neg()");
				}
				return(1);
			}
			if (siop_cmd->siop_tables.msg_in[2] == MSG_EXT_SDTR) {
				switch (siop_sdtr_neg(siop_cmd)) {
				case SIOP_NEG_MSGOUT:
					siop_update_scntl3(sc,
					    siop_cmd->siop_target);
					siop_table_sync(siop_cmd,
					    BUS_DMASYNC_PREREAD |
					    BUS_DMASYNC_PREWRITE);
					CALL_SCRIPT(Ent_send_msgout);
					return(1);
				case SIOP_NEG_ACK:
					siop_update_scntl3(sc,
					    siop_cmd->siop_target);
					CALL_SCRIPT(Ent_msgin_ack);
					return(1);
				default:
					panic("invalid retval from "
					    "siop_wdtr_neg()");
				}
				return(1);
			}
			/* send a message reject */
			siop_cmd->siop_tables.t_msgout.count = htole32(1);
			siop_cmd->siop_tables.t_msgout.addr =
			    htole32(siop_cmd->dsa);
			siop_cmd->siop_tables.msg_out[0] =
			    MSG_MESSAGE_REJECT;
			siop_table_sync(siop_cmd,
			    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
			CALL_SCRIPT(Ent_send_msgout);
			return 1;
		case A_int_disc:
			INCSTAT(siop_stat_intr_sdp);
			offset = bus_space_read_1(sc->sc_rt, sc->sc_rh,
			    SIOP_SCRATCHA + 1);
#ifdef DEBUG_DR
			printf("disconnect offset %d\n", offset);
#endif
			if (offset > SIOP_NSG) {
				printf("%s: bad offset for disconnect (%d)\n",
				    sc->sc_dev.dv_xname, offset);
				goto reset;
			}
			/*
			 * offset == SIOP_NSG may be a valid condition if
			 * we get a sdp when the xfer is done.
			 * Don't call memmove in this case.
			 */
			if (offset < SIOP_NSG) {
				memmove(&siop_cmd->siop_tables.data[0],
				    &siop_cmd->siop_tables.data[offset],
				    (SIOP_NSG - offset) * sizeof(scr_table_t));
				siop_table_sync(siop_cmd,
				    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
			}
			CALL_SCRIPT(Ent_script_sched);
			return 1;
		case A_int_resfail:
			printf("reselect failed\n");
			CALL_SCRIPT(Ent_script_sched);
			return  1;
		case A_int_done:
			if (xs == NULL) {
				printf("%s: done without command, DSA=0x%lx\n",
				    sc->sc_dev.dv_xname, (u_long)siop_cmd->dsa);
				siop_cmd->status = CMDST_FREE;
				siop_start(sc);
				CALL_SCRIPT(Ent_script_sched);
				return 1;
			}
			if (siop_target->status == TARST_PROBING &&
			    xs->sc_link->device_softc != NULL) {
				siop_target->status = TARST_ASYNC;
			}
#ifdef DEBUG_INTR
			printf("done, DSA=0x%lx target id 0x%x last msg "
			    "in=0x%x status=0x%x\n", (u_long)siop_cmd->dsa,
			    le32toh(siop_cmd->siop_tables.id),
			    siop_cmd->siop_tables.msg_in[0],
			    le32toh(siop_cmd->siop_tables.status));
#endif
			INCSTAT(siop_stat_intr_done);
			if (siop_cmd->status == CMDST_SENSE_ACTIVE)
				siop_cmd->status = CMDST_SENSE_DONE;
			else
				siop_cmd->status = CMDST_DONE;
			switch(le32toh(siop_cmd->siop_tables.status)) {
			case SCSI_OK:
				xs->error = (siop_cmd->status == CMDST_DONE) ?
				    XS_NOERROR : XS_SENSE;
				break;
			case SCSI_BUSY:
				xs->error = XS_BUSY;
				break;
			case SCSI_CHECK:
check_sense:
				if (siop_cmd->status == CMDST_SENSE_DONE) {
					/* request sense on a request sense ? */
					printf("request sense failed\n");
					xs->error = XS_DRIVER_STUFFUP;
				} else {
					siop_cmd->status = CMDST_SENSE;
				}
				break;
			case 0xff:
				/*
				 * the status byte was not updated, cmd was
				 * aborted
				 */
				xs->error = XS_SELTIMEOUT;
				break;
			default:
				xs->error = XS_DRIVER_STUFFUP;
			}
			goto end;
		default:
			printf("unknown irqcode %x\n", irqcode);
			xs->error = XS_SELTIMEOUT;
			goto end;
		}
		return 1;
	}
	/* We just should't get there */
	panic("siop_intr: I shouldn't be there !");
	return 1;
end:
	CALL_SCRIPT(Ent_script_sched);
	siop_scsicmd_end(siop_cmd);
	siop_lun->active = NULL;
	if (siop_cmd->status == CMDST_FREE) {
		if (freetarget) {
#ifdef DEBUG
			printf("%s: free siop_target for target %d lun %d "
			    "lunsw offset %d\n",
			    sc->sc_dev.dv_xname,
			    xs->sc_link->scsipi_scsi.target, lun,
			    sc->targets[xs->sc_link->scsipi_scsi.target]->lunsw->lunsw_off);
#endif
			/*
			 * nothing here, free the target struct and resel
			 * switch entry
			 */
			siop_script_write(sc, siop_cmd->siop_target->reseloff,
			    0x800c00ff);
			TAILQ_INSERT_TAIL(&sc->lunsw_list,
			    sc->targets[xs->sc_link->scsipi_scsi.target]->lunsw,
			    next);
			free(sc->targets[xs->sc_link->scsipi_scsi.target],
			    M_DEVBUF);
			sc->targets[xs->sc_link->scsipi_scsi.target] = NULL;
			siop_cmd->siop_target = NULL;
		}
		TAILQ_INSERT_TAIL(&sc->free_list, siop_cmd, next);
	}
	siop_start(sc);
	return 1;
}

void
siop_scsicmd_end(siop_cmd)
	struct siop_cmd *siop_cmd;
{
	struct scsipi_xfer *xs = siop_cmd->xs;
	struct siop_softc *sc = siop_cmd->siop_sc;

	if (siop_cmd->status != CMDST_SENSE_DONE &&
	    xs->xs_control & (XS_CTL_DATA_IN | XS_CTL_DATA_OUT)) {
		bus_dmamap_sync(sc->sc_dmat, siop_cmd->dmamap_data, 0,
		    siop_cmd->dmamap_data->dm_mapsize,
		    (xs->xs_control & XS_CTL_DATA_IN) ?
		    BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);
		bus_dmamap_unload(sc->sc_dmat, siop_cmd->dmamap_data);
	}
	bus_dmamap_unload(sc->sc_dmat, siop_cmd->dmamap_cmd);
	if (siop_cmd->status == CMDST_SENSE) {
		/* issue a request sense for this target */
		int error, i;
		siop_cmd->rs_cmd.opcode = REQUEST_SENSE;
		siop_cmd->rs_cmd.byte2 = xs->sc_link->scsipi_scsi.lun << 5;
		siop_cmd->rs_cmd.unused[0] = siop_cmd->rs_cmd.unused[1] = 0;
		siop_cmd->rs_cmd.length = sizeof(struct scsipi_sense_data);
		siop_cmd->rs_cmd.control = 0;
		siop_cmd->siop_tables.status = htole32(0xff);/*invalid status*/
		siop_cmd->siop_tables.t_msgout.count= htole32(1);
		siop_cmd->siop_tables.t_msgout.addr = htole32(siop_cmd->dsa);
		siop_cmd->siop_tables.msg_out[0] =
		    MSG_IDENTIFY(xs->sc_link->scsipi_scsi.lun, 1);
		error = bus_dmamap_load(sc->sc_dmat, siop_cmd->dmamap_cmd,
		    &siop_cmd->rs_cmd, sizeof(struct scsipi_sense),
		    NULL, BUS_DMA_NOWAIT);
		if (error) {
			printf("%s: unable to load cmd DMA map: %d",
			    sc->sc_dev.dv_xname, error);
			xs->error = XS_DRIVER_STUFFUP;
			goto out;
		}
		siop_cmd->siop_tables.cmd.count =
		    htole32(siop_cmd->dmamap_cmd->dm_segs[0].ds_len);
		siop_cmd->siop_tables.cmd.addr =
		    htole32(siop_cmd->dmamap_cmd->dm_segs[0].ds_addr);
		error = bus_dmamap_load(sc->sc_dmat, siop_cmd->dmamap_data,
		    &xs->sense.scsi_sense, sizeof(struct  scsipi_sense_data),
		    NULL, BUS_DMA_NOWAIT);
		if (error) {
			printf("%s: unable to load sense DMA map: %d",
			    sc->sc_dev.dv_xname, error);
			xs->error = XS_DRIVER_STUFFUP;
			bus_dmamap_unload(sc->sc_dmat, siop_cmd->dmamap_cmd);
			goto out;
		}
		for (i = 0; i < siop_cmd->dmamap_data->dm_nsegs; i++) {
			siop_cmd->siop_tables.data[i].count =
			    htole32(siop_cmd->dmamap_data->dm_segs[i].ds_len);
			siop_cmd->siop_tables.data[i].addr =
			    htole32(siop_cmd->dmamap_data->dm_segs[i].ds_addr);
		}
		bus_dmamap_sync(sc->sc_dmat, siop_cmd->dmamap_data, 0,
		    siop_cmd->dmamap_data->dm_mapsize, BUS_DMASYNC_PREREAD);
		bus_dmamap_sync(sc->sc_dmat, siop_cmd->dmamap_cmd, 0,
		    siop_cmd->dmamap_cmd->dm_mapsize, BUS_DMASYNC_PREWRITE);
		siop_table_sync(siop_cmd, BUS_DMASYNC_PREWRITE);
		/* arrange for the cmd to be handled now */
		TAILQ_INSERT_HEAD(&sc->ready_list, siop_cmd, next);
		return;
	} else if (siop_cmd->status == CMDST_SENSE_DONE) {
		bus_dmamap_sync(sc->sc_dmat, siop_cmd->dmamap_data, 0,
		    siop_cmd->dmamap_data->dm_mapsize, BUS_DMASYNC_POSTREAD);
		bus_dmamap_unload(sc->sc_dmat, siop_cmd->dmamap_data);
	}
out:
	callout_stop(&siop_cmd->xs->xs_callout);
	siop_cmd->status = CMDST_FREE;
	xs->xs_status |= XS_STS_DONE;
	xs->resid = 0;
	if ((xs->xs_control & XS_CTL_POLL) == 0)
		scsipi_done (xs);
}

/*
 * handle a rejected queue tag message: the command will run untagged,
 * has to adjust the reselect script.
 */
int
siop_handle_qtag_reject(siop_cmd)
	struct siop_cmd *siop_cmd;
{
#if 0
	struct siop_softc *sc = siop_cmd->siop_sc;
	int target = siop_cmd->xs->sc_link->scsipi_scsi.target;
	int lun = siop_cmd->xs->sc_link->scsipi_scsi.lun;
	int tag = siop_cmd->siop_tables.msg_out[2];
	int resel;
	u_int32_t *rscr;

	for (resel = 0; resel < sc->sc_nreselslots; resel++) {
		rscr = &sc->sc_resel[
			(Ent_res_nextld / 4) * resel];
		if ((htole32(rscr[Ent_rtarget / 4]) & 0x0f) == target &&
		    (htole32(rscr[Ent_rlun / 4]) & 0x0f) == lun &&
		    (htole32(rscr[Ent_rtag / 4]) & 0xff) == tag) {
			rscr[Ent_rtag / 4] = htole32(0x808400ff);
			return 0;
		}
	}
	printf("%s: reselect entry not found for target %d lun %d tag %d\n",
	    sc->sc_dev.dv_xname, target, lun, tag);
	return -1;
#endif
	return 0;
}

/*
 * handle a bus reset: reset chip, unqueue all active commands, free all
 * target struct and report loosage to upper layer.
 * As the upper layer may requeue immediatly we have to first store
 * all active commands in a temporary queue.
 */
void
siop_handle_reset(sc)
	struct siop_softc *sc;
{
	struct cmd_list reset_list;
	struct siop_cmd *siop_cmd, *next_siop_cmd;
	struct siop_lun *siop_lun;
	int target, lun;
	/*
	 * scsi bus reset. reset the chip and restart
	 * the queue. Need to clean up all active commands
	 */
	printf("%s: scsi bus reset\n", sc->sc_dev.dv_xname);
	/* stop, reset and restart the chip */
	siop_reset(sc);
	TAILQ_INIT(&reset_list);
	/* find all active commands */
	for (target = 0; target <= sc->sc_link.scsipi_scsi.max_target;
	    target++) {
		if (sc->targets[target] == NULL)
			continue;
		for (lun = 0; lun < 8; lun++) {
			siop_lun = &(sc->targets[target]->siop_lun[lun]);
			if (siop_lun == NULL)
				continue;
			siop_cmd = siop_lun->active;
			if (siop_cmd == NULL)
				continue;
			printf("cmd %p (target %d:%d) in reset list\n",
			    siop_cmd, target, lun);
			TAILQ_INSERT_TAIL(&reset_list, siop_cmd, next);
			siop_lun->active = NULL;
		}
		sc->targets[target]->status = TARST_ASYNC;
		sc->targets[target]->flags &= ~TARF_ISWIDE;
	}
	for (siop_cmd = TAILQ_FIRST(&sc->ready_list); siop_cmd != NULL;
	    siop_cmd = next_siop_cmd) {
		next_siop_cmd = TAILQ_NEXT(siop_cmd, next);
		if (siop_cmd->status != CMDST_SENSE)
			continue;
		printf("cmd %p (target %d:%d) in reset list (sense)\n",
		    siop_cmd, siop_cmd->xs->sc_link->scsipi_scsi.target,
		    siop_cmd->xs->sc_link->scsipi_scsi.lun);
		TAILQ_REMOVE(&sc->ready_list, siop_cmd, next);
		TAILQ_INSERT_TAIL(&reset_list, siop_cmd, next);
	}

	for (siop_cmd = TAILQ_FIRST(&reset_list); siop_cmd != NULL;
	    siop_cmd = next_siop_cmd) {
		next_siop_cmd = TAILQ_NEXT(siop_cmd, next);
		siop_cmd->xs->error = (siop_cmd->flags & CMDFL_TIMEOUT) ?
		    XS_TIMEOUT : XS_RESET;
		printf("cmd %p (status %d) about to be processed\n", siop_cmd,
		    siop_cmd->status);
		if (siop_cmd->status == CMDST_SENSE ||
		    siop_cmd->status == CMDST_SENSE_ACTIVE)
			siop_cmd->status = CMDST_SENSE_DONE;
		else
			siop_cmd->status = CMDST_DONE;
		TAILQ_REMOVE(&reset_list, siop_cmd, next);
		siop_scsicmd_end(siop_cmd);
		TAILQ_INSERT_TAIL(&sc->free_list, siop_cmd, next);
	}
}

int
siop_scsicmd(xs)
	struct scsipi_xfer *xs;
{
	struct siop_softc *sc = (struct siop_softc *)xs->sc_link->adapter_softc;
	struct siop_cmd *siop_cmd;
	int s, error, i;
	const int target = xs->sc_link->scsipi_scsi.target;
	const int lun = xs->sc_link->scsipi_scsi.lun;

	s = splbio();
#ifdef DEBUG_SCHED
	printf("starting cmd for %d:%d\n", target, lun);
#endif
	siop_cmd = TAILQ_FIRST(&sc->free_list);
	if (siop_cmd) {
		TAILQ_REMOVE(&sc->free_list, siop_cmd, next);
	} else {
		if (siop_morecbd(sc) == 0) {
			siop_cmd = TAILQ_FIRST(&sc->free_list);
#ifdef DIAGNOSTIC
			if (siop_cmd == NULL)
				panic("siop_morecbd succeed and does nothing");
#endif
			TAILQ_REMOVE(&sc->free_list, siop_cmd, next);
		}
	}
	if (siop_cmd == NULL) {
		xs->error = XS_DRIVER_STUFFUP;
		splx(s);
		return(TRY_AGAIN_LATER);
	}
#ifdef DIAGNOSTIC
	if (siop_cmd->status != CMDST_FREE)
		panic("siop_scsicmd: new cmd not free");
#endif
	if (sc->targets[target] == NULL) {
#ifdef DEBUG
		printf("%s: alloc siop_target for target %d\n",
			sc->sc_dev.dv_xname, target);
#endif
		sc->targets[target] =
		    malloc(sizeof(struct siop_target), M_DEVBUF, M_NOWAIT);
		if (sc->targets[target] == NULL) {
			printf("%s: can't malloc memory for target %d\n",
			    sc->sc_dev.dv_xname, target);
			xs->error = XS_DRIVER_STUFFUP;
			splx(s);
			return(TRY_AGAIN_LATER);
		}
		sc->targets[target]->status = TARST_PROBING;
		sc->targets[target]->flags = 0;
		sc->targets[target]->id = sc->clock_div << 24; /* scntl3 */
		sc->targets[target]->id |=  target << 16; /* id */
		/* sc->targets[target]->id |= 0x0 << 8; scxfer is 0 */

		/* get a lun switch script */
		sc->targets[target]->lunsw = siop_get_lunsw(sc);
		if (sc->targets[target]->lunsw == NULL) {
			printf("%s: can't alloc lunsw for target %d\n",
			    sc->sc_dev.dv_xname, target);
			xs->error = XS_DRIVER_STUFFUP;
			splx(s);
			return(TRY_AGAIN_LATER);
		}
		siop_add_reselsw(sc, target);
		for (i=0; i < 8; i++)
			sc->targets[target]->siop_lun[i].active = NULL;
	}
	siop_cmd->siop_target = sc->targets[target];
	siop_cmd->xs = xs;
	siop_cmd->flags = 0;
	siop_cmd->siop_tables.id = htole32(sc->targets[target]->id);
	siop_cmd->siop_tables.t_msgout.count= htole32(1);
	siop_cmd->siop_tables.t_msgout.addr = htole32(siop_cmd->dsa);
	memset(siop_cmd->siop_tables.msg_out, 0, 8);
	siop_cmd->siop_tables.msg_out[0] = MSG_IDENTIFY(lun, 1);
	if (sc->targets[target]->status == TARST_ASYNC) {
		if (sc->targets[target]->flags & TARF_WIDE) {
			sc->targets[target]->status = TARST_WIDE_NEG;
			siop_cmd->siop_tables.msg_out[1] = MSG_EXTENDED;
			siop_cmd->siop_tables.msg_out[2] = MSG_EXT_WDTR_LEN;
			siop_cmd->siop_tables.msg_out[3] = MSG_EXT_WDTR;
			siop_cmd->siop_tables.msg_out[4] =
			    MSG_EXT_WDTR_BUS_16_BIT;
			siop_cmd->siop_tables.t_msgout.count=
			    htole32(MSG_EXT_WDTR_LEN + 2 + 1);
		} else if (sc->targets[target]->flags & TARF_SYNC) {
			sc->targets[target]->status = TARST_SYNC_NEG;
			siop_cmd->siop_tables.msg_out[1] = MSG_EXTENDED;
			siop_cmd->siop_tables.msg_out[2] = MSG_EXT_SDTR_LEN;
			siop_cmd->siop_tables.msg_out[3] = MSG_EXT_SDTR;
			siop_cmd->siop_tables.msg_out[4] = sc->minsync;
			siop_cmd->siop_tables.msg_out[5] = sc->maxoff;
			siop_cmd->siop_tables.t_msgout.count=
			    htole32(MSG_EXT_SDTR_LEN + 2 +1);
		} else {
			sc->targets[target]->status = TARST_OK;
		}
	} else if (sc->targets[target]->status == TARST_OK &&
	    (sc->targets[target]->flags & TARF_TAG)) {
		siop_cmd->siop_tables.msg_out[1] = MSG_SIMPLE_Q_TAG;
		siop_cmd->siop_tables.msg_out[2] = 0;
		siop_cmd->siop_tables.t_msgout.count = htole32(3);
		siop_cmd->flags |= CMDFL_TAG;
	}
	siop_cmd->siop_tables.status = htole32(0xff); /* set invalid status */

	/* load the DMA maps */
	error = bus_dmamap_load(sc->sc_dmat, siop_cmd->dmamap_cmd,
	    xs->cmd, xs->cmdlen, NULL, BUS_DMA_NOWAIT);
	if (error) {
		printf("%s: unable to load cmd DMA map: %d",
		    sc->sc_dev.dv_xname, error);
		xs->error = XS_DRIVER_STUFFUP;
		splx(s);
		return(TRY_AGAIN_LATER);
	}
	siop_cmd->siop_tables.cmd.count =
	    htole32(siop_cmd->dmamap_cmd->dm_segs[0].ds_len);
	siop_cmd->siop_tables.cmd.addr =
	    htole32(siop_cmd->dmamap_cmd->dm_segs[0].ds_addr);
	if (xs->xs_control & (XS_CTL_DATA_IN | XS_CTL_DATA_OUT)) {
		error = bus_dmamap_load(sc->sc_dmat, siop_cmd->dmamap_data,
		    xs->data, xs->datalen, NULL, BUS_DMA_NOWAIT);
		if (error) {
			printf("%s: unable to load cmd DMA map: %d",
			    sc->sc_dev.dv_xname, error);
			xs->error = XS_DRIVER_STUFFUP;
			bus_dmamap_unload(sc->sc_dmat, siop_cmd->dmamap_cmd);
			splx(s);
			return(TRY_AGAIN_LATER);
		}
		for (i = 0; i < siop_cmd->dmamap_data->dm_nsegs; i++) {
			siop_cmd->siop_tables.data[i].count =
			    htole32(siop_cmd->dmamap_data->dm_segs[i].ds_len);
			siop_cmd->siop_tables.data[i].addr =
			    htole32(siop_cmd->dmamap_data->dm_segs[i].ds_addr);
		}
		bus_dmamap_sync(sc->sc_dmat, siop_cmd->dmamap_data, 0,
		    siop_cmd->dmamap_data->dm_mapsize,
		    (xs->xs_control & XS_CTL_DATA_IN) ?
		    BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);
	}
	bus_dmamap_sync(sc->sc_dmat, siop_cmd->dmamap_cmd, 0,
	    siop_cmd->dmamap_cmd->dm_mapsize, BUS_DMASYNC_PREWRITE);
	siop_table_sync(siop_cmd, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);

	siop_cmd->status = CMDST_READY;
	TAILQ_INSERT_TAIL(&sc->ready_list, siop_cmd, next);
	siop_start(sc);
	if (xs->xs_control & XS_CTL_POLL) {
		/* poll for command completion */
		while ((xs->xs_status & XS_STS_DONE) == 0) {
			delay(1000);
			siop_intr(sc);
		}
		splx(s);
		return (COMPLETE);
	}
	splx(s);
	return (SUCCESSFULLY_QUEUED);
}

void
siop_start(sc)
	struct siop_softc *sc;
{
	struct siop_cmd *siop_cmd, *next_siop_cmd;
	struct siop_lun *siop_lun;
	u_int32_t *scr;
	u_int32_t dsa;
	int timeout;
	int target, lun, tag, slot;
	int newcmd = 0;

	/*
	 * first make sure to read valid data
	 */
	siop_sched_sync(sc, BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);

	/*
	 * The queue management here is a bit tricky: the script always looks
	 * at the slot from first to last, so if we always use the first
	 * free slot commands can stay at the tail of the queue ~forever.
	 * The algorithm used here is to restart from the head when we know
	 * that the queue is empty, and only add commands after the last one.
	 * When we're at the end of the queue wait for the script to clear it.
	 * The best thing to do here would be to implement a circular queue,
	 * but using only 53c720 features this can be "interesting".
	 * A mid-way solution could be to implement 2 queues and swap orders.
	 */
	slot = sc->sc_currschedslot;
	scr = &sc->sc_sched[(Ent_nextslot / 4) * slot];
	/*
	 * if relative addr of first jump is not 0 the slot is free. As this is
	 * the last used slot, all previous slots are free, we can restart
	 * from 0.
	 */
	if (scr[(Ent_slot / 4) + 1] != 0) {
		slot = sc->sc_currschedslot = 0;
	} else {
		slot++;
	}

	for (siop_cmd = TAILQ_FIRST(&sc->ready_list); siop_cmd != NULL;
	    siop_cmd = next_siop_cmd) {
		next_siop_cmd = TAILQ_NEXT(siop_cmd, next);
#ifdef DIAGNOSTIC
		if (siop_cmd->status != CMDST_READY &&
		    siop_cmd->status != CMDST_SENSE)
			panic("siop: non-ready cmd in ready list");
#endif
		target = siop_cmd->xs->sc_link->scsipi_scsi.target;
		lun = siop_cmd->xs->sc_link->scsipi_scsi.lun;
		siop_lun = &(sc->targets[target]->siop_lun[lun]);
		if (siop_lun->active != NULL)
			continue;
		/* find a free scheduler slot and load it */
		for (; slot < sc->sc_nschedslots; slot++) {
			scr = &sc->sc_sched[(Ent_nextslot / 4) * slot];
			/*
			 * if relative addr of first jump is not 0 the
			 * slot is free
			 */
			if (scr[(Ent_slot / 4) + 1] != 0)
				break;
		}
		/* no more free slot, no need to continue */
		if (slot == sc->sc_nschedslots) {
			printf("out of slot\n");
			goto end;
		}
#ifdef DEBUG_SCHED
		printf("using slot %d for DSA 0x%lx\n", slot,
		    (u_long)siop_cmd->dsa);
#endif
		/* note that we started a new command */
		newcmd = 1;
		/* mark command as active */
		if (siop_cmd->status == CMDST_READY) {
			siop_cmd->status = CMDST_ACTIVE;
			tag = (siop_cmd->flags & CMDFL_TAG) ?
			    0x0 : 0xff;
		} else if (siop_cmd->status == CMDST_SENSE) {
			siop_cmd->status = CMDST_SENSE_ACTIVE;
			tag = 0xff;
			siop_cmd->siop_tables.t_msgout.count = htole32(1);
		} else
			panic("siop_start: bad status");
		TAILQ_REMOVE(&sc->ready_list, siop_cmd, next);
		siop_lun->active = siop_cmd;
		/* patch scripts with DSA addr */
		dsa = siop_cmd->dsa;
		/* first reselect switch */
		siop_script_write(sc, siop_lun->reseloff + 1,
		    dsa + sizeof(struct siop_xfer_common) + Ent_reload_dsa);
		/* then scheduler entry */
		scr[E_slot_abs_loaddsa_Used[0]] =
		    htole32(dsa + sizeof(struct siop_xfer_common));
#ifdef DEBUG_SCHED
		{ int j;
		printf("dump of slot:\n");
		for (j = 0; j < (sizeof(slot_script) / sizeof(slot_script[0]));
		    j +=2)
			printf("0x%x 0x%x\n", scr[j], scr[j+1]);
		}
#endif
		/* handle timeout */
		if (siop_cmd->status == CMDST_ACTIVE) {
			if ((siop_cmd->xs->xs_control &
			    XS_CTL_POLL) == 0) {
				/* start exire timer */
				timeout = (u_int64_t) siop_cmd->xs->timeout *
				    (u_int64_t)hz / 1000;
				if (timeout == 0)
					timeout = 1;
				callout_reset( &siop_cmd->xs->xs_callout,
				    timeout, siop_timeout, siop_cmd);
			}
		}
		/*
		 * Change jump offset so that this slot will be
		 * handled
		 */
		scr[(Ent_slot / 4) + 1] = 0;
		sc->sc_currschedslot = slot;
		slot++;
	}
end:
	/* if nothing changed no need to flush cache and wakeup script */
	if (newcmd == 0)
		return;
	/* make sure SCRIPT processor will read valid data */
	siop_sched_sync(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
	/* Signal script it has some work to do */
	bus_space_write_1(sc->sc_rt, sc->sc_rh, SIOP_ISTAT, ISTAT_SIGP);
	/* and wait for IRQ */
	return;
}

void
siop_timeout(v)
	void *v;
{
	struct siop_cmd *siop_cmd = v;
	struct siop_softc *sc = siop_cmd->siop_sc;
	int s;

	scsi_print_addr(siop_cmd->xs->sc_link);
	printf("command timeout\n");

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

	/* deactivate callout */
	callout_stop(&siop_cmd->xs->xs_callout);
	/* mark command as being timed out; siop_intr will handle it */
	/*
	 * mark command has being timed out and just return;
	 * the bus reset will generate an interrupt,
	 * it will be handled in siop_intr()
	 */
	siop_cmd->flags |= CMDFL_TIMEOUT;
	splx(s);
	return;

}

void
siop_dump_script(sc)
	struct siop_softc *sc;
{
	int i;
	siop_sched_sync(sc, BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
	for (i = 0; i < NBPG / 4; i += 2) {
		printf("0x%04x: 0x%08x 0x%08x", i * 4,
		    le32toh(sc->sc_script[i]), le32toh(sc->sc_script[i+1]));
		if ((le32toh(sc->sc_script[i]) & 0xe0000000) == 0xc0000000) {
			i++;
			printf(" 0x%08x", le32toh(sc->sc_script[i+1]));
		}
		printf("\n");
	}
}

int
siop_morecbd(sc)
	struct siop_softc *sc;
{
	int error, i, j;
	bus_dma_segment_t seg;
	int rseg;
	struct siop_cbd *newcbd;
	bus_addr_t dsa;
	u_int32_t *scr;

	/* allocate a new list head */
	newcbd = malloc(sizeof(struct siop_cbd), M_DEVBUF, M_NOWAIT);
	if (newcbd == NULL) {
		printf("%s: can't allocate memory for command descriptors "
		    "head\n", sc->sc_dev.dv_xname);
		return ENOMEM;
	}
	memset(newcbd, 0, sizeof(struct siop_cbd));

	/* allocate cmd list */
	newcbd->cmds =
	    malloc(sizeof(struct siop_cmd) * SIOP_NCMDPB, M_DEVBUF, M_NOWAIT);
	if (newcbd->cmds == NULL) {
		printf("%s: can't allocate memory for command descriptors\n",
		    sc->sc_dev.dv_xname);
		error = ENOMEM;
		goto bad3;
	}
	memset(newcbd->cmds, 0, sizeof(struct siop_cmd) * SIOP_NCMDPB);
	error = bus_dmamem_alloc(sc->sc_dmat, NBPG, NBPG, 0, &seg, 1, &rseg,
	    BUS_DMA_NOWAIT);
	if (error) {
		printf("%s: unable to allocate cbd DMA memory, error = %d\n",
		    sc->sc_dev.dv_xname, error);
		goto bad2;
	}
	error = bus_dmamem_map(sc->sc_dmat, &seg, rseg, NBPG,
	    (caddr_t *)&newcbd->xfers, BUS_DMA_NOWAIT|BUS_DMA_COHERENT);
	if (error) {
		printf("%s: unable to map cbd DMA memory, error = %d\n",
		    sc->sc_dev.dv_xname, error);
		goto bad2;
	}
	error = bus_dmamap_create(sc->sc_dmat, NBPG, 1, NBPG, 0,
	    BUS_DMA_NOWAIT, &newcbd->xferdma);
	if (error) {
		printf("%s: unable to create cbd DMA map, error = %d\n",
		    sc->sc_dev.dv_xname, error);
		goto bad1;
	}
	error = bus_dmamap_load(sc->sc_dmat, newcbd->xferdma, newcbd->xfers,
	    NBPG, NULL, BUS_DMA_NOWAIT);
	if (error) {
		printf("%s: unable to load cbd DMA map, error = %d\n",
		    sc->sc_dev.dv_xname, error);
		goto bad0;
	}
#ifdef DEBUG
	printf("newcdb PHY addr: 0x%lx\n",
	    (unsigned long)newcbd->xferdma->dm_segs[0].ds_addr);
#endif

	for (i = 0; i < SIOP_NCMDPB; i++) {
		error = bus_dmamap_create(sc->sc_dmat, MAXPHYS, SIOP_NSG,
		    MAXPHYS, 0, BUS_DMA_NOWAIT | BUS_DMA_ALLOCNOW,
		    &newcbd->cmds[i].dmamap_data);
		if (error) {
			printf("%s: unable to create data DMA map for cbd: "
			    "error %d\n",
			    sc->sc_dev.dv_xname, error);
			goto bad0;
		}
		error = bus_dmamap_create(sc->sc_dmat,
		    sizeof(struct scsipi_generic), 1,
		    sizeof(struct scsipi_generic), 0,
		    BUS_DMA_NOWAIT | BUS_DMA_ALLOCNOW,
		    &newcbd->cmds[i].dmamap_cmd);
		if (error) {
			printf("%s: unable to create cmd DMA map for cbd %d\n",
			    sc->sc_dev.dv_xname, error);
			goto bad0;
		}
		newcbd->cmds[i].siop_sc = sc;
		newcbd->cmds[i].siop_cbdp = newcbd;
		newcbd->cmds[i].siop_xfer = &newcbd->xfers[i];
		memset(newcbd->cmds[i].siop_xfer, 0,
		    sizeof(struct siop_xfer));
		newcbd->cmds[i].dsa = newcbd->xferdma->dm_segs[0].ds_addr +
		    i * sizeof(struct siop_xfer);
		dsa = newcbd->cmds[i].dsa;
		newcbd->cmds[i].status = CMDST_FREE;
		newcbd->cmds[i].siop_tables.t_msgout.count= htole32(1);
		newcbd->cmds[i].siop_tables.t_msgout.addr = htole32(dsa);
		newcbd->cmds[i].siop_tables.t_msgin.count= htole32(1);
		newcbd->cmds[i].siop_tables.t_msgin.addr = htole32(dsa + 8);
		newcbd->cmds[i].siop_tables.t_extmsgin.count= htole32(2);
		newcbd->cmds[i].siop_tables.t_extmsgin.addr = htole32(
		    le32toh(newcbd->cmds[i].siop_tables.t_msgin.addr) + 1);
		newcbd->cmds[i].siop_tables.t_msgtag.count= htole32(2);
		newcbd->cmds[i].siop_tables.t_msgtag.addr = htole32(
		    le32toh(newcbd->cmds[i].siop_tables.t_msgin.addr) + 1);
		newcbd->cmds[i].siop_tables.t_status.count= htole32(1);
		newcbd->cmds[i].siop_tables.t_status.addr = htole32(
		    le32toh(newcbd->cmds[i].siop_tables.t_msgin.addr) + 8);

		/* The reselect script */
		scr = &newcbd->cmds[i].siop_xfer->resel[0];
		for (j = 0; j < sizeof(load_dsa) / sizeof(load_dsa[0]); j++)
			scr[j] = htole32(load_dsa[j]);
		/*
		 * 0x78000000 is a 'move data8 to reg'. data8 is the second
		 * octet, reg offset is the third.
		 */
		scr[Ent_rdsa0 / 4] =
		    htole32(0x78100000 | ((dsa & 0x000000ff) <<  8));
		scr[Ent_rdsa1 / 4] =
		    htole32(0x78110000 | ( dsa & 0x0000ff00       ));
		scr[Ent_rdsa2 / 4] =
		    htole32(0x78120000 | ((dsa & 0x00ff0000) >>  8));
		scr[Ent_rdsa3 / 4] =
		    htole32(0x78130000 | ((dsa & 0xff000000) >> 16));
		for (j = 0;
		    j < (sizeof(E_resel_abs_reselected_Used) /
		    sizeof(E_resel_abs_reselected_Used[0])); j++)
			scr[E_resel_abs_reselected_Used[j]] =
			    htole32(sc->sc_scriptaddr + Ent_reselected);
		TAILQ_INSERT_TAIL(&sc->free_list, &newcbd->cmds[i], next);
#ifdef DEBUG
		printf("tables[%d]: in=0x%x out=0x%x status=0x%x\n", i,
		    le32toh(newcbd->cmds[i].siop_tables.t_msgin.addr),
		    le32toh(newcbd->cmds[i].siop_tables.t_msgout.addr),
		    le32toh(newcbd->cmds[i].siop_tables.t_status.addr));
		for (j = 0; j < sizeof(load_dsa) / sizeof(load_dsa[0]);
		    j += 2) {
			printf("0x%x 0x%x\n", scr[j], scr[j+1]);
		}
#endif
	}
	TAILQ_INSERT_TAIL(&sc->cmds, newcbd, next);
	return 0;
bad0:
	bus_dmamap_destroy(sc->sc_dmat, newcbd->xferdma);
bad1:
	bus_dmamem_free(sc->sc_dmat, &seg, rseg);
bad2:
	free(newcbd->cmds, M_DEVBUF);
bad3:
	free(newcbd, M_DEVBUF);
	return error;
}

struct siop_lunsw *
siop_get_lunsw(sc)
	struct siop_softc *sc;
{
	struct siop_lunsw *lunsw;
	int i;

	lunsw = TAILQ_FIRST(&sc->lunsw_list);
	if (lunsw != NULL) {
#ifdef DEBUG
		printf("siop_get_lunsw got lunsw at offset %d\n",
		    lunsw->lunsw_off);
#endif
		TAILQ_REMOVE(&sc->lunsw_list, lunsw, next);
		return lunsw;
	}
	lunsw = malloc(sizeof(struct siop_lunsw), M_DEVBUF, M_NOWAIT);
	if (lunsw == NULL)
		return NULL;
	memset(lunsw, 0, sizeof(struct siop_lunsw));
#ifdef DEBUG
	printf("allocating lunsw at offset %d\n", sc->ram_free);
#endif
	if (sc->features & SF_CHIP_RAM) {
		bus_space_write_region_4(sc->sc_ramt, sc->sc_ramh,
		    sc->ram_free * 4, lun_switch,
		    sizeof(lun_switch) / sizeof(lun_switch[0]));
		bus_space_write_4(sc->sc_ramt, sc->sc_ramh,
		    (sc->ram_free + E_abs_lunsw_return_Used[0]) * 4,
		    sc->sc_scriptaddr + Ent_lunsw_return);
	} else {
		for (i = 0; i < sizeof(lun_switch) / sizeof(lun_switch[0]);
		    i++)
			sc->sc_script[sc->ram_free + i] =
			    htole32(lun_switch[i]);
		sc->sc_script[sc->ram_free + E_abs_lunsw_return_Used[0]] =
		    htole32(sc->sc_scriptaddr + Ent_lunsw_return);
	}
	lunsw->lunsw_off = sc->ram_free;
	sc->ram_free += sizeof(lun_switch) / sizeof(lun_switch[0]);
	if (sc->ram_free > 1024)
		printf("%s: ram_free (%d) > 1024\n", sc->sc_dev.dv_xname,
		    sc->ram_free);
	return lunsw;
}

void
siop_add_reselsw(sc, target)
	struct siop_softc *sc;
	int target;
{
	int i;
	struct siop_lun *siop_lun;
	/* add an entry to resel switch */
	for (i = 0; i < 15; i++) {
		sc->targets[target]->reseloff = Ent_resel_targ0 / 4 + i * 2;
		if ((siop_script_read(sc, sc->targets[target]->reseloff) & 0xff)
		    == 0xff) { /* it's free */
#ifdef DEBUG
			printf("siop: target %d slot %d offset %d\n",
			    target, i, sc->targets[target]->reseloff);
#endif
			/* JUMP abs_foo, IF target | 0x80; */
			siop_script_write(sc, sc->targets[target]->reseloff,
			    0x800c0080 | target);
			siop_script_write(sc, sc->targets[target]->reseloff + 1,
			    sc->sc_scriptaddr +
			    sc->targets[target]->lunsw->lunsw_off * 4);
			break;
		}
	}
	if (i == 15) /* no free slot, shouldn't happen */
		panic("siop: resel switch full");

	for (i = 0; i < 8; i++) {
		siop_lun = &(sc->targets[target]->siop_lun[i]);
		siop_lun->reseloff =
		    sc->targets[target]->lunsw->lunsw_off +
			(Ent_resel_lun0 / 4) + (i * 2);
	}
	siop_update_scntl3(sc, sc->targets[target]);
}

void
siop_update_scntl3(sc, siop_target)
	struct siop_softc *sc;
	struct siop_target *siop_target;
{
	/* MOVE target->id >> 24 TO SCNTL3 */
	siop_script_write(sc,
	    siop_target->lunsw->lunsw_off + (Ent_restore_scntl3 / 4),
	    0x78030000 | ((siop_target->id >> 16) & 0x0000ff00));
	/* MOVE target->id >> 8 TO SXFER */
	siop_script_write(sc,
	    siop_target->lunsw->lunsw_off + (Ent_restore_scntl3 / 4) + 2,
	    0x78050000 | (siop_target->id & 0x0000ff00));
}

#ifdef SIOP_STATS
void
siop_printstats()
{
	printf("siop_stat_intr %d\n", siop_stat_intr);
	printf("siop_stat_intr_shortxfer %d\n", siop_stat_intr_shortxfer);
	printf("siop_stat_intr_xferdisc %d\n", siop_stat_intr_xferdisc);
	printf("siop_stat_intr_sdp %d\n", siop_stat_intr_sdp);
	printf("siop_stat_intr_done %d\n", siop_stat_intr_done);
}
#endif