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aic7xxx.c revision 1.77
      1 /*	$NetBSD: aic7xxx.c,v 1.77 2001/07/07 16:13:46 thorpej Exp $	*/
      2 
      3 /*
      4  * Generic driver for the aic7xxx based adaptec SCSI controllers
      5  * Product specific probe and attach routines can be found in:
      6  * i386/eisa/ahc_eisa.c	27/284X and aic7770 motherboard controllers
      7  * pci/ahc_pci.c	3985, 3980, 3940, 2940, aic7895, aic7890,
      8  *			aic7880, aic7870, aic7860, and aic7850 controllers
      9  *
     10  * Copyright (c) 1994, 1995, 1996, 1997, 1998, 1999, 2000 Justin T. Gibbs.
     11  * All rights reserved.
     12  *
     13  * Redistribution and use in source and binary forms, with or without
     14  * modification, are permitted provided that the following conditions
     15  * are met:
     16  * 1. Redistributions of source code must retain the above copyright
     17  *    notice, this list of conditions, and the following disclaimer,
     18  *    without modification.
     19  * 2. The name of the author may not be used to endorse or promote products
     20  *    derived from this software without specific prior written permission.
     21  *
     22  * Alternatively, this software may be distributed under the terms of the
     23  * the GNU Public License ("GPL").
     24  *
     25  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
     26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     28  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
     29  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     35  * SUCH DAMAGE.
     36  *
     37  * $FreeBSD: src/sys/dev/aic7xxx/aic7xxx.c,v 1.42 2000/03/18 22:28:18 gibbs Exp $
     38  */
     39 /*
     40  * A few notes on features of the driver.
     41  *
     42  * SCB paging takes advantage of the fact that devices stay disconnected
     43  * from the bus a relatively long time and that while they're disconnected,
     44  * having the SCBs for these transactions down on the host adapter is of
     45  * little use.  Instead of leaving this idle SCB down on the card we copy
     46  * it back up into kernel memory and reuse the SCB slot on the card to
     47  * schedule another transaction.  This can be a real payoff when doing random
     48  * I/O to tagged queueing devices since there are more transactions active at
     49  * once for the device to sort for optimal seek reduction. The algorithm goes
     50  * like this...
     51  *
     52  * The sequencer maintains two lists of its hardware SCBs.  The first is the
     53  * singly linked free list which tracks all SCBs that are not currently in
     54  * use.  The second is the doubly linked disconnected list which holds the
     55  * SCBs of transactions that are in the disconnected state sorted most
     56  * recently disconnected first.  When the kernel queues a transaction to
     57  * the card, a hardware SCB to "house" this transaction is retrieved from
     58  * either of these two lists.  If the SCB came from the disconnected list,
     59  * a check is made to see if any data transfer or SCB linking (more on linking
     60  * in a bit) information has been changed since it was copied from the host
     61  * and if so, DMAs the SCB back up before it can be used.  Once a hardware
     62  * SCB has been obtained, the SCB is DMAed from the host.  Before any work
     63  * can begin on this SCB, the sequencer must ensure that either the SCB is
     64  * for a tagged transaction or the target is not already working on another
     65  * non-tagged transaction.  If a conflict arises in the non-tagged case, the
     66  * sequencer finds the SCB for the active transactions and sets the SCB_LINKED
     67  * field in that SCB to this next SCB to execute.  To facilitate finding
     68  * active non-tagged SCBs, the last four bytes of up to the first four hardware
     69  * SCBs serve as a storage area for the currently active SCB ID for each
     70  * target.
     71  *
     72  * When a device reconnects, a search is made of the hardware SCBs to find
     73  * the SCB for this transaction.  If the search fails, a hardware SCB is
     74  * pulled from either the free or disconnected SCB list and the proper
     75  * SCB is DMAed from the host.  If the MK_MESSAGE control bit is set
     76  * in the control byte of the SCB while it was disconnected, the sequencer
     77  * will assert ATN and attempt to issue a message to the host.
     78  *
     79  * When a command completes, a check for non-zero status and residuals is
     80  * made.  If either of these conditions exists, the SCB is DMAed back up to
     81  * the host so that it can interpret this information.  Additionally, in the
     82  * case of bad status, the sequencer generates a special interrupt and pauses
     83  * itself.  This allows the host to setup a request sense command if it
     84  * chooses for this target synchronously with the error so that sense
     85  * information isn't lost.
     86  *
     87  */
     88 
     89 #include "opt_ddb.h"
     90 #include "opt_ahc.h"
     91 
     92 #include <sys/param.h>
     93 #include <sys/kernel.h>
     94 #include <sys/systm.h>
     95 #include <sys/device.h>
     96 #include <sys/malloc.h>
     97 #include <sys/buf.h>
     98 #include <sys/proc.h>
     99 #include <sys/scsiio.h>
    100 
    101 #include <machine/bus.h>
    102 #include <machine/intr.h>
    103 
    104 #include <dev/scsipi/scsi_all.h>
    105 #include <dev/scsipi/scsipi_all.h>
    106 #include <dev/scsipi/scsi_message.h>
    107 #include <dev/scsipi/scsipi_debug.h>
    108 #include <dev/scsipi/scsiconf.h>
    109 
    110 #include <uvm/uvm_extern.h>
    111 
    112 #include <dev/ic/aic7xxxvar.h>
    113 #include <dev/microcode/aic7xxx/sequencer.h>
    114 #include <dev/microcode/aic7xxx/aic7xxx_reg.h>
    115 #include <dev/microcode/aic7xxx/aic7xxx_seq.h>
    116 
    117 #define ALL_CHANNELS '\0'
    118 #define ALL_TARGETS_MASK 0xFFFF
    119 #define INITIATOR_WILDCARD	(~0)
    120 
    121 #define	SIM_IS_SCSIBUS_B(ahc, periph)	\
    122 	((periph)->periph_channel->chan_channel == 1)
    123 #define	SIM_CHANNEL(ahc, periph)	\
    124 	(SIM_IS_SCSIBUS_B(ahc, periph) ? 'B' : 'A')
    125 #define	SIM_SCSI_ID(ahc, periph)	\
    126 	(SIM_IS_SCSIBUS_B(ahc, periph) ? ahc->our_id_b : ahc->our_id)
    127 #define	SCB_IS_SCSIBUS_B(scb)	\
    128 	(((scb)->hscb->tcl & SELBUSB) != 0)
    129 #define	SCB_TARGET(scb)	\
    130 	(((scb)->hscb->tcl & TID) >> 4)
    131 #define	SCB_CHANNEL(scb) \
    132 	(SCB_IS_SCSIBUS_B(scb) ? 'B' : 'A')
    133 #define	SCB_LUN(scb)	\
    134 	((scb)->hscb->tcl & LID)
    135 #define SCB_TARGET_OFFSET(scb)		\
    136 	(SCB_TARGET(scb) + (SCB_IS_SCSIBUS_B(scb) ? 8 : 0))
    137 #define SCB_TARGET_MASK(scb)		\
    138 	(0x01 << (SCB_TARGET_OFFSET(scb)))
    139 #define TCL_CHANNEL(ahc, tcl)		\
    140 	((((ahc)->features & AHC_TWIN) && ((tcl) & SELBUSB)) ? 'B' : 'A')
    141 #define TCL_SCSI_ID(ahc, tcl)		\
    142 	(TCL_CHANNEL((ahc), (tcl)) == 'B' ? (ahc)->our_id_b : (ahc)->our_id)
    143 #define TCL_TARGET(tcl) (((tcl) & TID) >> TCL_TARGET_SHIFT)
    144 #define TCL_LUN(tcl) ((tcl) & LID)
    145 
    146 #define XS_TCL(ahc, xs) \
    147 	((((xs)->xs_periph->periph_target << 4) & 0xF0) \
    148 	    | (SIM_IS_SCSIBUS_B((ahc), (xs)->xs_periph) ? SELBUSB : 0) \
    149 	    | ((xs)->xs_periph->periph_lun & 0x07))
    150 
    151 const char * const ahc_chip_names[] =
    152 {
    153 	"NONE",
    154 	"aic7770",
    155 	"aic7850",
    156 	"aic7855",
    157 	"aic7859",
    158 	"aic7860",
    159 	"aic7870",
    160 	"aic7880",
    161 	"aic7890/91",
    162 	"aic7892",
    163 	"aic7895",
    164 	"aic7896/97",
    165 	"aic7899"
    166 };
    167 
    168 typedef enum {
    169 	ROLE_UNKNOWN,
    170 	ROLE_INITIATOR,
    171 	ROLE_TARGET
    172 } role_t;
    173 
    174 struct ahc_devinfo {
    175 	int	  our_scsiid;
    176 	int	  target_offset;
    177 	u_int16_t target_mask;
    178 	u_int8_t  target;
    179 	u_int8_t  lun;
    180 	char	  channel;
    181 	role_t	  role;		/*
    182 				 * Only guaranteed to be correct if not
    183 				 * in the busfree state.
    184 				 */
    185 };
    186 
    187 typedef enum {
    188 	SEARCH_COMPLETE,
    189 	SEARCH_COUNT,
    190 	SEARCH_REMOVE
    191 } ahc_search_action;
    192 
    193 #ifdef AHC_DEBUG
    194 static int     ahc_debug = AHC_DEBUG;
    195 #endif
    196 
    197 static int	ahcinitscbdata(struct ahc_softc *);
    198 static void	ahcfiniscbdata(struct ahc_softc *);
    199 
    200 #if UNUSED
    201 static void	ahc_dump_targcmd(struct target_cmd *);
    202 #endif
    203 static void	ahc_shutdown(void *arg);
    204 static void	ahc_action(struct scsipi_channel *,
    205 				scsipi_adapter_req_t, void *);
    206 static int	ahc_ioctl(struct scsipi_channel *, u_long, caddr_t, int,
    207 			  struct proc *);
    208 static void	ahc_execute_scb(void *, bus_dma_segment_t *, int);
    209 static int	ahc_poll(struct ahc_softc *, int);
    210 static void	ahc_setup_data(struct ahc_softc *, struct scsipi_xfer *,
    211 			       struct scb *);
    212 static void	ahc_freeze_devq(struct ahc_softc *, struct scsipi_periph *);
    213 static void	ahcallocscbs(struct ahc_softc *);
    214 #if UNUSED
    215 static void	ahc_scb_devinfo(struct ahc_softc *, struct ahc_devinfo *,
    216 				struct scb *);
    217 #endif
    218 static void	ahc_fetch_devinfo(struct ahc_softc *, struct ahc_devinfo *);
    219 static void	ahc_compile_devinfo(struct ahc_devinfo *, u_int, u_int, u_int,
    220 				    char, role_t);
    221 static u_int	ahc_abort_wscb(struct ahc_softc *, u_int, u_int);
    222 static void	ahc_done(struct ahc_softc *, struct scb *);
    223 static struct tmode_tstate *
    224 		ahc_alloc_tstate(struct ahc_softc *, u_int, char);
    225 #if UNUSED
    226 static void	ahc_free_tstate(struct ahc_softc *, u_int, char, int);
    227 #endif
    228 static void 	ahc_handle_seqint(struct ahc_softc *, u_int);
    229 static void	ahc_handle_scsiint(struct ahc_softc *, u_int);
    230 static void	ahc_build_transfer_msg(struct ahc_softc *,
    231 				       struct ahc_devinfo *);
    232 static void	ahc_setup_initiator_msgout(struct ahc_softc *,
    233 					   struct ahc_devinfo *,
    234 					   struct scb *);
    235 static void	ahc_setup_target_msgin(struct ahc_softc *,
    236 				       struct ahc_devinfo *);
    237 static void	ahc_clear_msg_state(struct ahc_softc *);
    238 static void	ahc_handle_message_phase(struct ahc_softc *,
    239 					 struct scsipi_periph *);
    240 static int	ahc_sent_msg(struct ahc_softc *, u_int, int);
    241 
    242 static int	ahc_parse_msg(struct ahc_softc *, struct scsipi_periph *,
    243 			      struct ahc_devinfo *);
    244 static void	ahc_handle_ign_wide_residue(struct ahc_softc *,
    245 					    struct ahc_devinfo *);
    246 static void	ahc_handle_devreset(struct ahc_softc *, struct ahc_devinfo *,
    247 				    int, char *, int);
    248 #ifdef AHC_DUMP_SEQ
    249 static void	ahc_dumpseq(struct ahc_softc *);
    250 #endif
    251 static void	ahc_loadseq(struct ahc_softc *);
    252 static int	ahc_check_patch(struct ahc_softc *, const struct patch **,
    253 				int, int *);
    254 static void	ahc_download_instr(struct ahc_softc *, int, u_int8_t *);
    255 static int	ahc_match_scb(struct scb *, int, char, int, u_int, role_t);
    256 #if defined(AHC_DEBUG)
    257 static void	ahc_print_scb(struct scb *);
    258 #endif
    259 static int	ahc_search_qinfifo(struct ahc_softc *, int, char, int, u_int,
    260 				   role_t, scb_flag, ahc_search_action);
    261 static int	ahc_reset_channel(struct ahc_softc *, char, int);
    262 static int	ahc_abort_scbs(struct ahc_softc *, int, char, int, u_int,
    263 			       role_t, int);
    264 static int	ahc_search_disc_list(struct ahc_softc *, int,
    265 				     char, int, u_int, int, int, int);
    266 static u_int	ahc_rem_scb_from_disc_list(struct ahc_softc *, u_int, u_int);
    267 static void	ahc_add_curscb_to_free_list(struct ahc_softc *);
    268 static void	ahc_clear_intstat(struct ahc_softc *);
    269 static void	ahc_reset_current_bus(struct ahc_softc *);
    270 static const struct ahc_syncrate *
    271 		ahc_devlimited_syncrate(struct ahc_softc *, u_int *);
    272 static const struct ahc_syncrate *
    273 		ahc_find_syncrate(struct ahc_softc *, u_int *, u_int);
    274 static u_int	ahc_find_period(struct ahc_softc *, u_int, u_int);
    275 static void	ahc_validate_offset(struct ahc_softc *,
    276 				const struct ahc_syncrate *, u_int *, int);
    277 static void	ahc_update_target_msg_request(struct ahc_softc *,
    278 					      struct ahc_devinfo *,
    279 					      struct ahc_initiator_tinfo *,
    280 					      int, int);
    281 static void	ahc_set_syncrate(struct ahc_softc *, struct ahc_devinfo *,
    282 				 const struct ahc_syncrate *, u_int, u_int,
    283 				 u_int, int, int);
    284 static void	ahc_set_width(struct ahc_softc *, struct ahc_devinfo *,
    285 			      u_int, u_int, int, int);
    286 static void	ahc_set_tags(struct ahc_softc *, struct ahc_devinfo *, int);
    287 static void	ahc_update_xfer_mode(struct ahc_softc *, struct ahc_devinfo *);
    288 static void	ahc_construct_sdtr(struct ahc_softc *, u_int, u_int);
    289 
    290 static void	ahc_construct_wdtr(struct ahc_softc *, u_int);
    291 
    292 static void	ahc_calc_residual(struct scb *);
    293 
    294 static void	ahc_update_pending_syncrates(struct ahc_softc *);
    295 
    296 static void	ahc_set_recoveryscb(struct ahc_softc *, struct scb *);
    297 
    298 static void     ahc_timeout (void *);
    299 static __inline int  sequencer_paused(struct ahc_softc *);
    300 static __inline void pause_sequencer(struct ahc_softc *);
    301 static __inline void unpause_sequencer(struct ahc_softc *);
    302 static 		void restart_sequencer(struct ahc_softc *);
    303 static __inline u_int ahc_index_busy_tcl(struct ahc_softc *, u_int, int);
    304 
    305 static __inline void	 ahc_busy_tcl(struct ahc_softc *, struct scb *);
    306 static __inline int	ahc_isbusy_tcl(struct ahc_softc *, struct scb *);
    307 
    308 static __inline void	   ahc_freeze_ccb(struct scb *);
    309 static __inline void	   ahcsetccbstatus(struct scsipi_xfer *, int);
    310 static void		   ahc_run_qoutfifo(struct ahc_softc *);
    311 
    312 static __inline struct ahc_initiator_tinfo *
    313 			   ahc_fetch_transinfo(struct ahc_softc *,
    314 					       char, u_int, u_int,
    315 					       struct tmode_tstate **);
    316 static void	   ahcfreescb(struct ahc_softc *, struct scb *);
    317 static __inline	struct scb *ahcgetscb(struct ahc_softc *);
    318 
    319 static int ahc_createdmamem(bus_dma_tag_t, int, int, bus_dmamap_t *,
    320 			    caddr_t *, bus_addr_t *, bus_dma_segment_t *,
    321 			    int *, const char *, const char *);
    322 static void ahc_freedmamem(bus_dma_tag_t, int, bus_dmamap_t,
    323 			   caddr_t, bus_dma_segment_t *, int);
    324 static void ahcminphys(struct buf *);
    325 
    326 static __inline void ahc_swap_hscb(struct hardware_scb *);
    327 static __inline void ahc_swap_sg(struct ahc_dma_seg *);
    328 static int ahc_istagged_device(struct ahc_softc *, struct scsipi_xfer *, int);
    329 
    330 #if defined(AHC_DEBUG) && 0
    331 static void ahc_dumptinfo(struct ahc_softc *, struct ahc_initiator_tinfo *);
    332 #endif
    333 
    334 static __inline void
    335 ahc_swap_hscb(struct hardware_scb *hscb)
    336 {
    337 	hscb->SG_pointer = htole32(hscb->SG_pointer);
    338 	hscb->data = htole32(hscb->data);
    339 	hscb->datalen = htole32(hscb->datalen);
    340 	/*
    341 	 * No need to swap cmdpointer; it's either 0 or set to
    342 	 * cmdstore_busaddr, which is already swapped.
    343 	 */
    344 }
    345 
    346 static __inline void
    347 ahc_swap_sg(struct ahc_dma_seg *sg)
    348 {
    349 	sg->addr = htole32(sg->addr);
    350 	sg->len = htole32(sg->len);
    351 }
    352 
    353 static void
    354 ahcminphys(bp)
    355 	struct buf *bp;
    356 {
    357 /*
    358  * Even though the card can transfer up to 16megs per command
    359  * we are limited by the number of segments in the dma segment
    360  * list that we can hold.  The worst case is that all pages are
    361  * discontinuous physically, hense the "page per segment" limit
    362  * enforced here.
    363  */
    364 	if (bp->b_bcount > AHC_MAXTRANSFER_SIZE) {
    365 		bp->b_bcount = AHC_MAXTRANSFER_SIZE;
    366 	}
    367 	minphys(bp);
    368 }
    369 
    370 
    371 static __inline u_int32_t
    372 ahc_hscb_busaddr(struct ahc_softc *ahc, u_int index)
    373 {
    374 	return (ahc->scb_data->hscb_busaddr
    375 		+ (sizeof(struct hardware_scb) * index));
    376 }
    377 
    378 #define AHC_BUSRESET_DELAY	25	/* Reset delay in us */
    379 
    380 static __inline int
    381 sequencer_paused(struct ahc_softc *ahc)
    382 {
    383 	return ((ahc_inb(ahc, HCNTRL) & PAUSE) != 0);
    384 }
    385 
    386 static __inline void
    387 pause_sequencer(struct ahc_softc *ahc)
    388 {
    389 	ahc_outb(ahc, HCNTRL, ahc->pause);
    390 
    391 	/*
    392 	 * Since the sequencer can disable pausing in a critical section, we
    393 	 * must loop until it actually stops.
    394 	 */
    395 	while (sequencer_paused(ahc) == 0)
    396 		;
    397 }
    398 
    399 static __inline void
    400 unpause_sequencer(struct ahc_softc *ahc)
    401 {
    402 	if ((ahc_inb(ahc, INTSTAT) & (SCSIINT | SEQINT | BRKADRINT)) == 0)
    403 		ahc_outb(ahc, HCNTRL, ahc->unpause);
    404 }
    405 
    406 /*
    407  * Restart the sequencer program from address zero
    408  */
    409 static void
    410 restart_sequencer(struct ahc_softc *ahc)
    411 {
    412 	u_int i;
    413 
    414 	pause_sequencer(ahc);
    415 
    416 	/*
    417 	 * Everytime we restart the sequencer, there
    418 	 * is the possiblitity that we have restarted
    419 	 * within a three instruction window where an
    420 	 * SCB has been marked free but has not made it
    421 	 * onto the free list.  Since SCSI events(bus reset,
    422 	 * unexpected bus free) will always freeze the
    423 	 * sequencer, we cannot close this window.  To
    424 	 * avoid losing an SCB, we reconsitute the free
    425 	 * list every time we restart the sequencer.
    426 	 */
    427 	ahc_outb(ahc, FREE_SCBH, SCB_LIST_NULL);
    428 	for (i = 0; i < ahc->scb_data->maxhscbs; i++) {
    429 
    430 		ahc_outb(ahc, SCBPTR, i);
    431 		if (ahc_inb(ahc, SCB_TAG) == SCB_LIST_NULL)
    432 			ahc_add_curscb_to_free_list(ahc);
    433 	}
    434 	ahc_outb(ahc, SEQCTL, FASTMODE|SEQRESET);
    435 	unpause_sequencer(ahc);
    436 }
    437 
    438 static __inline u_int
    439 ahc_index_busy_tcl(struct ahc_softc *ahc, u_int tcl, int unbusy)
    440 {
    441 	u_int scbid;
    442 
    443 	scbid = ahc->untagged_scbs[tcl];
    444 	if (unbusy) {
    445 		ahc->untagged_scbs[tcl] = SCB_LIST_NULL;
    446 		bus_dmamap_sync(ahc->parent_dmat, ahc->shared_data_dmamap,
    447 		    UNTAGGEDSCB_OFFSET * 256, 256, BUS_DMASYNC_PREWRITE);
    448 	}
    449 
    450 	return (scbid);
    451 }
    452 
    453 static __inline void
    454 ahc_busy_tcl(struct ahc_softc *ahc, struct scb *scb)
    455 {
    456 	ahc->untagged_scbs[scb->hscb->tcl] = scb->hscb->tag;
    457 	bus_dmamap_sync(ahc->parent_dmat, ahc->shared_data_dmamap,
    458 	    UNTAGGEDSCB_OFFSET * 256, 256, BUS_DMASYNC_PREWRITE);
    459 }
    460 
    461 static __inline int
    462 ahc_isbusy_tcl(struct ahc_softc *ahc, struct scb *scb)
    463 {
    464 	return ahc->untagged_scbs[scb->hscb->tcl] != SCB_LIST_NULL;
    465 }
    466 
    467 static __inline void
    468 ahc_freeze_ccb(struct scb *scb)
    469 {
    470 	struct scsipi_xfer *xs = scb->xs;
    471 
    472 	if (!(scb->flags & SCB_FREEZE_QUEUE)) {
    473 		scsipi_periph_freeze(xs->xs_periph, 1);
    474 		scb->flags |= SCB_FREEZE_QUEUE;
    475 	}
    476 }
    477 
    478 static __inline void
    479 ahcsetccbstatus(struct scsipi_xfer *xs, int status)
    480 {
    481 	xs->error = status;
    482 }
    483 
    484 static __inline struct ahc_initiator_tinfo *
    485 ahc_fetch_transinfo(struct ahc_softc *ahc, char channel, u_int our_id,
    486 		    u_int remote_id, struct tmode_tstate **tstate)
    487 {
    488 	/*
    489 	 * Transfer data structures are stored from the perspective
    490 	 * of the target role.  Since the parameters for a connection
    491 	 * in the initiator role to a given target are the same as
    492 	 * when the roles are reversed, we pretend we are the target.
    493 	 */
    494 	if (channel == 'B')
    495 		our_id += 8;
    496 	*tstate = ahc->enabled_targets[our_id];
    497 	return (&(*tstate)->transinfo[remote_id]);
    498 }
    499 
    500 static void
    501 ahc_run_qoutfifo(struct ahc_softc *ahc)
    502 {
    503 	struct scb *scb;
    504 	u_int  scb_index;
    505 
    506 	bus_dmamap_sync(ahc->parent_dmat, ahc->shared_data_dmamap, 0,
    507 	     256, BUS_DMASYNC_POSTREAD);
    508 
    509 	while (ahc->qoutfifo[ahc->qoutfifonext] != SCB_LIST_NULL) {
    510 		scb_index = ahc->qoutfifo[ahc->qoutfifonext];
    511 		ahc->qoutfifo[ahc->qoutfifonext++] = SCB_LIST_NULL;
    512 
    513 		scb = &ahc->scb_data->scbarray[scb_index];
    514 		if (scb_index >= ahc->scb_data->numscbs
    515 		  || (scb->flags & SCB_ACTIVE) == 0) {
    516 			printf("%s: WARNING no command for scb %d "
    517 			       "(cmdcmplt)\nQOUTPOS = %d\n",
    518 			       ahc_name(ahc), scb_index,
    519 			       ahc->qoutfifonext - 1);
    520 			continue;
    521 		}
    522 
    523 		/*
    524 		 * Save off the residual
    525 		 * if there is one.
    526 		 */
    527 		if (scb->hscb->residual_SG_count != 0)
    528 			ahc_calc_residual(scb);
    529 		else
    530 			scb->xs->resid = 0;
    531 #ifdef AHC_DEBUG
    532 		if (ahc_debug & AHC_SHOWSCBS) {
    533 			scsipi_printaddr(scb->xs->xs_periph);
    534 			printf("run_qoutfifo: SCB %x complete\n",
    535 			    scb->hscb->tag);
    536 		}
    537 #endif
    538 		ahc_done(ahc, scb);
    539 	}
    540 }
    541 
    542 
    543 /*
    544  * An scb (and hence an scb entry on the board) is put onto the
    545  * free list.
    546  */
    547 static void
    548 ahcfreescb(struct ahc_softc *ahc, struct scb *scb)
    549 {
    550 	struct hardware_scb *hscb;
    551 	int opri;
    552 
    553 	hscb = scb->hscb;
    554 
    555 #ifdef AHC_DEBUG
    556 	if (ahc_debug & AHC_SHOWSCBALLOC)
    557 		printf("%s: free SCB tag %x\n", ahc_name(ahc), hscb->tag);
    558 #endif
    559 
    560 	opri = splbio();
    561 
    562 	if ((ahc->flags & AHC_RESOURCE_SHORTAGE) != 0 ||
    563 	    (scb->flags & SCB_RECOVERY_SCB) != 0) {
    564 		ahc->flags &= ~AHC_RESOURCE_SHORTAGE;
    565 		scsipi_channel_thaw(&ahc->sc_channel, 1);
    566 		if (ahc->features & AHC_TWIN)
    567 			scsipi_channel_thaw(&ahc->sc_channel_b, 1);
    568 	}
    569 
    570 	/* Clean up for the next user */
    571 	scb->flags = SCB_FREE;
    572 	hscb->control = 0;
    573 	hscb->status = 0;
    574 
    575 	SLIST_INSERT_HEAD(&ahc->scb_data->free_scbs, scb, links);
    576 
    577 	splx(opri);
    578 }
    579 
    580 /*
    581  * Get a free scb, either one already assigned to a hardware slot
    582  * on the adapter or one that will require an SCB to be paged out before
    583  * use. If there are none, see if we can allocate a new SCB.  Otherwise
    584  * either return an error or sleep.
    585  */
    586 static __inline struct scb *
    587 ahcgetscb(struct ahc_softc *ahc)
    588 {
    589 	struct scb *scbp;
    590 	int opri;;
    591 
    592 	opri = splbio();
    593 	if ((scbp = SLIST_FIRST(&ahc->scb_data->free_scbs))) {
    594 		SLIST_REMOVE_HEAD(&ahc->scb_data->free_scbs, links);
    595 	} else {
    596 		ahcallocscbs(ahc);
    597 		scbp = SLIST_FIRST(&ahc->scb_data->free_scbs);
    598 		if (scbp != NULL)
    599 			SLIST_REMOVE_HEAD(&ahc->scb_data->free_scbs, links);
    600 	}
    601 
    602 	splx(opri);
    603 
    604 #ifdef AHC_DEBUG
    605 	if (ahc_debug & AHC_SHOWSCBALLOC) {
    606 		if (scbp != NULL)
    607 			printf("%s: new SCB, tag %x\n", ahc_name(ahc),
    608 			    scbp->hscb->tag);
    609 		else
    610 			printf("%s: failed to allocate new SCB\n",
    611 			    ahc_name(ahc));
    612 	}
    613 #endif
    614 
    615 	return (scbp);
    616 }
    617 
    618 static int
    619 ahc_createdmamem(tag, size, flags, mapp, vaddr, baddr, seg, nseg, myname, what)
    620 	bus_dma_tag_t tag;
    621 	int size;
    622 	int flags;
    623 	bus_dmamap_t *mapp;
    624 	caddr_t *vaddr;
    625 	bus_addr_t *baddr;
    626 	bus_dma_segment_t *seg;
    627 	int *nseg;
    628 	const char *myname, *what;
    629 {
    630 	int error, level = 0;
    631 
    632 	if ((error = bus_dmamem_alloc(tag, size, PAGE_SIZE, 0,
    633 			seg, 1, nseg, BUS_DMA_NOWAIT)) != 0) {
    634 		printf("%s: failed to allocate DMA mem for %s, error = %d\n",
    635 			myname, what, error);
    636 		goto out;
    637 	}
    638 	level++;
    639 
    640 	if ((error = bus_dmamem_map(tag, seg, *nseg, size, vaddr,
    641 			BUS_DMA_NOWAIT|BUS_DMA_COHERENT)) != 0) {
    642 		printf("%s: failed to map DMA mem for %s, error = %d\n",
    643 			myname, what, error);
    644 		goto out;
    645 	}
    646 	level++;
    647 
    648 	if ((error = bus_dmamap_create(tag, size, 1, size, 0,
    649 			BUS_DMA_NOWAIT | flags, mapp)) != 0) {
    650                 printf("%s: failed to create DMA map for %s, error = %d\n",
    651 			myname, what, error);
    652 		goto out;
    653         }
    654 	level++;
    655 
    656 	if ((error = bus_dmamap_load(tag, *mapp, *vaddr, size, NULL,
    657 			BUS_DMA_NOWAIT)) != 0) {
    658                 printf("%s: failed to load DMA map for %s, error = %d\n",
    659 			myname, what, error);
    660 		goto out;
    661         }
    662 
    663 	*baddr = (*mapp)->dm_segs[0].ds_addr;
    664 
    665 #ifdef AHC_DEBUG
    666 	printf("%s: dmamem for %s at busaddr %lx virt %lx nseg %d size %d\n",
    667 	    myname, what, (unsigned long)*baddr, (unsigned long)*vaddr,
    668 	    *nseg, size);
    669 #endif
    670 
    671 	return 0;
    672 out:
    673 	switch (level) {
    674 	case 3:
    675 		bus_dmamap_destroy(tag, *mapp);
    676 		/* FALLTHROUGH */
    677 	case 2:
    678 		bus_dmamem_unmap(tag, *vaddr, size);
    679 		/* FALLTHROUGH */
    680 	case 1:
    681 		bus_dmamem_free(tag, seg, *nseg);
    682 		break;
    683 	default:
    684 		break;
    685 	}
    686 
    687 	return error;
    688 }
    689 
    690 static void
    691 ahc_freedmamem(tag, size, map, vaddr, seg, nseg)
    692 	bus_dma_tag_t tag;
    693 	int size;
    694 	bus_dmamap_t map;
    695 	caddr_t vaddr;
    696 	bus_dma_segment_t *seg;
    697 	int nseg;
    698 {
    699 
    700 	bus_dmamap_unload(tag, map);
    701 	bus_dmamap_destroy(tag, map);
    702 	bus_dmamem_unmap(tag, vaddr, size);
    703 	bus_dmamem_free(tag, seg, nseg);
    704 }
    705 
    706 char *
    707 ahc_name(struct ahc_softc *ahc)
    708 {
    709 	return (ahc->sc_dev.dv_xname);
    710 }
    711 
    712 #ifdef AHC_DEBUG
    713 static void
    714 ahc_print_scb(struct scb *scb)
    715 {
    716 	struct hardware_scb *hscb = scb->hscb;
    717 
    718 	printf("scb:%p tag %x control:0x%x tcl:0x%x cmdlen:%d cmdpointer:0x%lx\n",
    719 		scb,
    720 		hscb->tag,
    721 		hscb->control,
    722 		hscb->tcl,
    723 		hscb->cmdlen,
    724 		(unsigned long)le32toh(hscb->cmdpointer));
    725 	printf("        datlen:%u data:0x%lx segs:0x%x segp:0x%lx\n",
    726 		le32toh(hscb->datalen),
    727 		(unsigned long)(le32toh(hscb->data)),
    728 		hscb->SG_count,
    729 		(unsigned long)(le32toh(hscb->SG_pointer)));
    730 	printf("	sg_addr:%lx sg_len:%lu\n",
    731 		(unsigned long)(le32toh(scb->sg_list[0].addr)),
    732 		(unsigned long)(le32toh(scb->sg_list[0].len)));
    733 	printf("	cdb:%x %x %x %x %x %x %x %x %x %x %x %x\n",
    734 		hscb->cmdstore[0], hscb->cmdstore[1], hscb->cmdstore[2],
    735 		hscb->cmdstore[3], hscb->cmdstore[4], hscb->cmdstore[5],
    736 		hscb->cmdstore[6], hscb->cmdstore[7], hscb->cmdstore[8],
    737 		hscb->cmdstore[9], hscb->cmdstore[10], hscb->cmdstore[11]);
    738 }
    739 #endif
    740 
    741 static const struct {
    742         u_int8_t errno;
    743 	const char *errmesg;
    744 } hard_error[] = {
    745 	{ ILLHADDR,	"Illegal Host Access" },
    746 	{ ILLSADDR,	"Illegal Sequencer Address referrenced" },
    747 	{ ILLOPCODE,	"Illegal Opcode in sequencer program" },
    748 	{ SQPARERR,	"Sequencer Parity Error" },
    749 	{ DPARERR,	"Data-path Parity Error" },
    750 	{ MPARERR,	"Scratch or SCB Memory Parity Error" },
    751 	{ PCIERRSTAT,	"PCI Error detected" },
    752 	{ CIOPARERR,	"CIOBUS Parity Error" },
    753 };
    754 static const int num_errors = sizeof(hard_error)/sizeof(hard_error[0]);
    755 
    756 static const struct {
    757         u_int8_t phase;
    758         u_int8_t mesg_out; /* Message response to parity errors */
    759 	const char *phasemsg;
    760 } phase_table[] = {
    761 	{ P_DATAOUT,	MSG_NOOP,		"in Data-out phase"	},
    762 	{ P_DATAIN,	MSG_INITIATOR_DET_ERR,	"in Data-in phase"	},
    763 	{ P_COMMAND,	MSG_NOOP,		"in Command phase"	},
    764 	{ P_MESGOUT,	MSG_NOOP,		"in Message-out phase"	},
    765 	{ P_STATUS,	MSG_INITIATOR_DET_ERR,	"in Status phase"	},
    766 	{ P_MESGIN,	MSG_PARITY_ERROR,	"in Message-in phase"	},
    767 	{ P_BUSFREE,	MSG_NOOP,		"while idle"		},
    768 	{ 0,		MSG_NOOP,		"in unknown phase"	}
    769 };
    770 static const int num_phases = (sizeof(phase_table)/sizeof(phase_table[0])) - 1;
    771 
    772 /*
    773  * Valid SCSIRATE values.  (p. 3-17)
    774  * Provides a mapping of tranfer periods in ns to the proper value to
    775  * stick in the scsiscfr reg to use that transfer rate.
    776  */
    777 #define AHC_SYNCRATE_DT		0
    778 #define AHC_SYNCRATE_ULTRA2	1
    779 #define AHC_SYNCRATE_ULTRA	3
    780 #define AHC_SYNCRATE_FAST	6
    781 static const struct ahc_syncrate ahc_syncrates[] = {
    782       /* ultra2    fast/ultra  period     rate */
    783 	{ 0x42,      0x000,      9,      "80.0" },
    784 	{ 0x03,      0x000,     10,      "40.0" },
    785 	{ 0x04,      0x000,     11,      "33.0" },
    786 	{ 0x05,      0x100,     12,      "20.0" },
    787 	{ 0x06,      0x110,     15,      "16.0" },
    788 	{ 0x07,      0x120,     18,      "13.4" },
    789 	{ 0x08,      0x000,     25,      "10.0" },
    790 	{ 0x19,      0x010,     31,      "8.0"  },
    791 	{ 0x1a,      0x020,     37,      "6.67" },
    792 	{ 0x1b,      0x030,     43,      "5.7"  },
    793 	{ 0x1c,      0x040,     50,      "5.0"  },
    794 	{ 0x00,      0x050,     56,      "4.4"  },
    795 	{ 0x00,      0x060,     62,      "4.0"  },
    796 	{ 0x00,      0x070,     68,      "3.6"  },
    797 	{ 0x00,      0x000,      0,      NULL   }
    798 };
    799 
    800 /*
    801  * Allocate a controller structure for a new device and initialize it.
    802  */
    803 int
    804 ahc_alloc(struct ahc_softc *ahc, bus_space_handle_t sh, bus_space_tag_t st,
    805 	  bus_dma_tag_t parent_dmat, ahc_chip chip, ahc_feature features,
    806 	  ahc_flag flags)
    807 {
    808 	struct scb_data *scb_data;
    809 
    810 	scb_data = malloc(sizeof (struct scb_data), M_DEVBUF, M_NOWAIT);
    811 	if (scb_data == NULL) {
    812 		printf("%s: cannot malloc softc!\n", ahc_name(ahc));
    813 		return -1;
    814 	}
    815 	memset(scb_data, 0, sizeof (struct scb_data));
    816 	LIST_INIT(&ahc->pending_ccbs);
    817 	ahc->tag = st;
    818 	ahc->bsh = sh;
    819 	ahc->parent_dmat = parent_dmat;
    820 	ahc->chip = chip;
    821 	ahc->features = features;
    822 	ahc->flags = flags;
    823 	ahc->scb_data = scb_data;
    824 
    825 	ahc->unpause = (ahc_inb(ahc, HCNTRL) & IRQMS) | INTEN;
    826 	/* The IRQMS bit is only valid on VL and EISA chips */
    827 	if ((ahc->chip & AHC_PCI) != 0)
    828 		ahc->unpause &= ~IRQMS;
    829 	ahc->pause = ahc->unpause | PAUSE;
    830 	return (0);
    831 }
    832 
    833 void
    834 ahc_free(ahc)
    835 	struct ahc_softc *ahc;
    836 {
    837 	ahcfiniscbdata(ahc);
    838 	if (ahc->init_level != 0)
    839 		ahc_freedmamem(ahc->parent_dmat, ahc->shared_data_size,
    840 		    ahc->shared_data_dmamap, ahc->qoutfifo,
    841 		    &ahc->shared_data_seg, ahc->shared_data_nseg);
    842 
    843 	if (ahc->scb_data != NULL)
    844 		free(ahc->scb_data, M_DEVBUF);
    845 	if (ahc->bus_data != NULL)
    846 		free(ahc->bus_data, M_DEVBUF);
    847 	return;
    848 }
    849 
    850 static int
    851 ahcinitscbdata(struct ahc_softc *ahc)
    852 {
    853 	struct scb_data *scb_data;
    854 	int i;
    855 
    856 	scb_data = ahc->scb_data;
    857 	SLIST_INIT(&scb_data->free_scbs);
    858 	SLIST_INIT(&scb_data->sg_maps);
    859 
    860 	/* Allocate SCB resources */
    861 	scb_data->scbarray =
    862 	    (struct scb *)malloc(sizeof(struct scb) * AHC_SCB_MAX,
    863 				 M_DEVBUF, M_NOWAIT);
    864 	if (scb_data->scbarray == NULL)
    865 		return (ENOMEM);
    866 	memset(scb_data->scbarray, 0, sizeof(struct scb) * AHC_SCB_MAX);
    867 
    868 	/* Determine the number of hardware SCBs and initialize them */
    869 
    870 	scb_data->maxhscbs = ahc_probe_scbs(ahc);
    871 	/* SCB 0 heads the free list */
    872 	ahc_outb(ahc, FREE_SCBH, 0);
    873 	for (i = 0; i < ahc->scb_data->maxhscbs; i++) {
    874 		ahc_outb(ahc, SCBPTR, i);
    875 
    876 		/* Clear the control byte. */
    877 		ahc_outb(ahc, SCB_CONTROL, 0);
    878 
    879 		/* Set the next pointer */
    880 		ahc_outb(ahc, SCB_NEXT, i+1);
    881 
    882 		/* Make the tag number invalid */
    883 		ahc_outb(ahc, SCB_TAG, SCB_LIST_NULL);
    884 	}
    885 
    886 	/* Make sure that the last SCB terminates the free list */
    887 	ahc_outb(ahc, SCBPTR, i-1);
    888 	ahc_outb(ahc, SCB_NEXT, SCB_LIST_NULL);
    889 
    890 	/* Ensure we clear the 0 SCB's control byte. */
    891 	ahc_outb(ahc, SCBPTR, 0);
    892 	ahc_outb(ahc, SCB_CONTROL, 0);
    893 
    894 	scb_data->maxhscbs = i;
    895 
    896 	if (ahc->scb_data->maxhscbs == 0)
    897 		panic("%s: No SCB space found", ahc_name(ahc));
    898 
    899 	/*
    900 	 * Create our DMA tags.  These tags define the kinds of device
    901 	 * accessible memory allocations and memory mappings we will
    902 	 * need to perform during normal operation.
    903 	 *
    904 	 * Unless we need to further restrict the allocation, we rely
    905 	 * on the restrictions of the parent dmat, hence the common
    906 	 * use of MAXADDR and MAXSIZE.
    907 	 */
    908 
    909 	if (ahc_createdmamem(ahc->parent_dmat,
    910 	    AHC_SCB_MAX * sizeof(struct hardware_scb), ahc->sc_dmaflags,
    911 	    &scb_data->hscb_dmamap,
    912 	    (caddr_t *)&scb_data->hscbs, &scb_data->hscb_busaddr,
    913 	    &scb_data->hscb_seg, &scb_data->hscb_nseg, ahc_name(ahc),
    914 	    "hardware SCB structures") < 0)
    915 		goto error_exit;
    916 
    917 	scb_data->init_level++;
    918 
    919 	if (ahc_createdmamem(ahc->parent_dmat,
    920 	    AHC_SCB_MAX * sizeof(struct scsipi_sense_data), ahc->sc_dmaflags,
    921 	    &scb_data->sense_dmamap, (caddr_t *)&scb_data->sense,
    922 	    &scb_data->sense_busaddr, &scb_data->sense_seg,
    923 	    &scb_data->sense_nseg, ahc_name(ahc), "sense buffers") < 0)
    924 		goto error_exit;
    925 
    926 	scb_data->init_level++;
    927 
    928 	/* Perform initial CCB allocation */
    929 	memset(scb_data->hscbs, 0, AHC_SCB_MAX * sizeof(struct hardware_scb));
    930 	ahcallocscbs(ahc);
    931 
    932 	if (scb_data->numscbs == 0) {
    933 		printf("%s: ahc_init_scb_data - "
    934 		       "Unable to allocate initial scbs\n",
    935 		       ahc_name(ahc));
    936 		goto error_exit;
    937 	}
    938 
    939 	scb_data->init_level++;
    940 
    941 	/*
    942          * Note that we were successfull
    943          */
    944         return 0;
    945 
    946 error_exit:
    947 
    948 	return ENOMEM;
    949 }
    950 
    951 static void
    952 ahcfiniscbdata(struct ahc_softc *ahc)
    953 {
    954 	struct scb_data *scb_data;
    955 
    956 	scb_data = ahc->scb_data;
    957 
    958 	switch (scb_data->init_level) {
    959 	default:
    960 	case 3:
    961 	{
    962 		struct sg_map_node *sg_map;
    963 
    964 		while ((sg_map = SLIST_FIRST(&scb_data->sg_maps))!= NULL) {
    965 			SLIST_REMOVE_HEAD(&scb_data->sg_maps, links);
    966 			ahc_freedmamem(ahc->parent_dmat, PAGE_SIZE,
    967 			    sg_map->sg_dmamap, (caddr_t)sg_map->sg_vaddr,
    968 			    &sg_map->sg_dmasegs, sg_map->sg_nseg);
    969 			free(sg_map, M_DEVBUF);
    970 		}
    971 	}
    972 	/*FALLTHROUGH*/
    973 	case 2:
    974 		ahc_freedmamem(ahc->parent_dmat,
    975 		    AHC_SCB_MAX * sizeof(struct scsipi_sense_data),
    976 		    scb_data->sense_dmamap, (caddr_t)scb_data->sense,
    977 		    &scb_data->sense_seg, scb_data->sense_nseg);
    978 	/*FALLTHROUGH*/
    979 	case 1:
    980 		ahc_freedmamem(ahc->parent_dmat,
    981 		    AHC_SCB_MAX * sizeof(struct hardware_scb),
    982 		    scb_data->hscb_dmamap, (caddr_t)scb_data->hscbs,
    983 		    &scb_data->hscb_seg, scb_data->hscb_nseg);
    984 	/*FALLTHROUGH*/
    985 	}
    986 	if (scb_data->scbarray != NULL)
    987 		free(scb_data->scbarray, M_DEVBUF);
    988 }
    989 
    990 int
    991 ahc_reset(struct ahc_softc *ahc)
    992 {
    993 	u_int	sblkctl;
    994 	int	wait;
    995 
    996 #ifdef AHC_DUMP_SEQ
    997 	if (ahc->init_level == 0)
    998 		ahc_dumpseq(ahc);
    999 #endif
   1000 	ahc_outb(ahc, HCNTRL, CHIPRST | ahc->pause);
   1001 	/*
   1002 	 * Ensure that the reset has finished
   1003 	 */
   1004 	wait = 1000;
   1005 	do {
   1006 		DELAY(1000);
   1007 	} while (--wait && !(ahc_inb(ahc, HCNTRL) & CHIPRSTACK));
   1008 
   1009 	if (wait == 0) {
   1010 		printf("%s: WARNING - Failed chip reset!  "
   1011 		       "Trying to initialize anyway.\n", ahc_name(ahc));
   1012 	}
   1013 	ahc_outb(ahc, HCNTRL, ahc->pause);
   1014 
   1015 	/* Determine channel configuration */
   1016 	sblkctl = ahc_inb(ahc, SBLKCTL) & (SELBUSB|SELWIDE);
   1017 	/* No Twin Channel PCI cards */
   1018 	if ((ahc->chip & AHC_PCI) != 0)
   1019 		sblkctl &= ~SELBUSB;
   1020 	switch (sblkctl) {
   1021 	case 0:
   1022 		/* Single Narrow Channel */
   1023 		break;
   1024 	case 2:
   1025 		/* Wide Channel */
   1026 		ahc->features |= AHC_WIDE;
   1027 		break;
   1028 	case 8:
   1029 		/* Twin Channel */
   1030 		ahc->features |= AHC_TWIN;
   1031 		break;
   1032 	default:
   1033 		printf(" Unsupported adapter type.  Ignoring\n");
   1034 		return(-1);
   1035 	}
   1036 
   1037 	return (0);
   1038 }
   1039 
   1040 /*
   1041  * Called when we have an active connection to a target on the bus,
   1042  * this function finds the nearest syncrate to the input period limited
   1043  * by the capabilities of the bus connectivity of the target.
   1044  */
   1045 static const struct ahc_syncrate *
   1046 ahc_devlimited_syncrate(struct ahc_softc *ahc, u_int *period) {
   1047 	u_int	maxsync;
   1048 
   1049 	if ((ahc->features & AHC_ULTRA2) != 0) {
   1050 		if ((ahc_inb(ahc, SBLKCTL) & ENAB40) != 0
   1051 		 && (ahc_inb(ahc, SSTAT2) & EXP_ACTIVE) == 0) {
   1052 			maxsync = AHC_SYNCRATE_ULTRA2;
   1053 		} else {
   1054 			maxsync = AHC_SYNCRATE_ULTRA;
   1055 		}
   1056 	} else if ((ahc->features & AHC_ULTRA) != 0) {
   1057 		maxsync = AHC_SYNCRATE_ULTRA;
   1058 	} else {
   1059 		maxsync = AHC_SYNCRATE_FAST;
   1060 	}
   1061 	return (ahc_find_syncrate(ahc, period, maxsync));
   1062 }
   1063 
   1064 /*
   1065  * Look up the valid period to SCSIRATE conversion in our table.
   1066  * Return the period and offset that should be sent to the target
   1067  * if this was the beginning of an SDTR.
   1068  */
   1069 static const struct ahc_syncrate *
   1070 ahc_find_syncrate(struct ahc_softc *ahc, u_int *period, u_int maxsync)
   1071 {
   1072 	const struct ahc_syncrate *syncrate;
   1073 
   1074 	syncrate = &ahc_syncrates[maxsync];
   1075 	while ((syncrate->rate != NULL)
   1076 	    && ((ahc->features & AHC_ULTRA2) == 0
   1077 	     || (syncrate->sxfr_u2 != 0))) {
   1078 
   1079 		if (*period <= syncrate->period) {
   1080 			/*
   1081 			 * When responding to a target that requests
   1082 			 * sync, the requested rate may fall between
   1083 			 * two rates that we can output, but still be
   1084 			 * a rate that we can receive.  Because of this,
   1085 			 * we want to respond to the target with
   1086 			 * the same rate that it sent to us even
   1087 			 * if the period we use to send data to it
   1088 			 * is lower.  Only lower the response period
   1089 			 * if we must.
   1090 			 */
   1091 			if (syncrate == &ahc_syncrates[maxsync])
   1092 				*period = syncrate->period;
   1093 			break;
   1094 		}
   1095 		syncrate++;
   1096 	}
   1097 
   1098 	if ((*period == 0)
   1099 	 || (syncrate->rate == NULL)
   1100 	 || ((ahc->features & AHC_ULTRA2) != 0
   1101 	  && (syncrate->sxfr_u2 == 0))) {
   1102 		/* Use asynchronous transfers. */
   1103 		*period = 0;
   1104 		syncrate = NULL;
   1105 	}
   1106 	return (syncrate);
   1107 }
   1108 
   1109 static u_int
   1110 ahc_find_period(struct ahc_softc *ahc, u_int scsirate, u_int maxsync)
   1111 {
   1112 	const struct ahc_syncrate *syncrate;
   1113 
   1114 	if ((ahc->features & AHC_ULTRA2) != 0)
   1115 		scsirate &= SXFR_ULTRA2;
   1116 	else
   1117 		scsirate &= SXFR;
   1118 
   1119 	syncrate = &ahc_syncrates[maxsync];
   1120 	while (syncrate->rate != NULL) {
   1121 
   1122 		if ((ahc->features & AHC_ULTRA2) != 0) {
   1123 			if (syncrate->sxfr_u2 == 0)
   1124 				break;
   1125 			else if (scsirate == (syncrate->sxfr_u2 & SXFR_ULTRA2))
   1126 				return (syncrate->period);
   1127 		} else if (scsirate == (syncrate->sxfr & SXFR)) {
   1128 				return (syncrate->period);
   1129 		}
   1130 		syncrate++;
   1131 	}
   1132 	return (0); /* async */
   1133 }
   1134 
   1135 static void
   1136 ahc_validate_offset(struct ahc_softc *ahc, const struct ahc_syncrate *syncrate,
   1137 		    u_int *offset, int wide)
   1138 {
   1139 	u_int maxoffset;
   1140 
   1141 	/* Limit offset to what we can do */
   1142 	if (syncrate == NULL) {
   1143 		maxoffset = 0;
   1144 	} else if ((ahc->features & AHC_ULTRA2) != 0) {
   1145 		maxoffset = MAX_OFFSET_ULTRA2;
   1146 	} else {
   1147 		if (wide)
   1148 			maxoffset = MAX_OFFSET_16BIT;
   1149 		else
   1150 			maxoffset = MAX_OFFSET_8BIT;
   1151 	}
   1152 	*offset = MIN(*offset, maxoffset);
   1153 }
   1154 
   1155 static void
   1156 ahc_update_target_msg_request(struct ahc_softc *ahc,
   1157 			      struct ahc_devinfo *devinfo,
   1158 			      struct ahc_initiator_tinfo *tinfo,
   1159 			      int force, int paused)
   1160 {
   1161 	u_int targ_msg_req_orig;
   1162 
   1163 	targ_msg_req_orig = ahc->targ_msg_req;
   1164 	if (tinfo->current.period != tinfo->goal.period
   1165 	 || tinfo->current.width != tinfo->goal.width
   1166 	 || tinfo->current.offset != tinfo->goal.offset
   1167 	 || (force
   1168 	  && (tinfo->goal.period != 0
   1169 	   || tinfo->goal.width != MSG_EXT_WDTR_BUS_8_BIT))) {
   1170 		ahc->targ_msg_req |= devinfo->target_mask;
   1171 	} else {
   1172 		ahc->targ_msg_req &= ~devinfo->target_mask;
   1173 	}
   1174 
   1175 	if (ahc->targ_msg_req != targ_msg_req_orig) {
   1176 		/* Update the message request bit for this target */
   1177 		if ((ahc->features & AHC_HS_MAILBOX) != 0) {
   1178 			if (paused) {
   1179 				ahc_outb(ahc, TARGET_MSG_REQUEST,
   1180 					 ahc->targ_msg_req & 0xFF);
   1181 				ahc_outb(ahc, TARGET_MSG_REQUEST + 1,
   1182 					 (ahc->targ_msg_req >> 8) & 0xFF);
   1183 			} else {
   1184 				ahc_outb(ahc, HS_MAILBOX,
   1185 					 0x01 << HOST_MAILBOX_SHIFT);
   1186 			}
   1187 		} else {
   1188 			if (!paused)
   1189 				pause_sequencer(ahc);
   1190 
   1191 			ahc_outb(ahc, TARGET_MSG_REQUEST,
   1192 				 ahc->targ_msg_req & 0xFF);
   1193 			ahc_outb(ahc, TARGET_MSG_REQUEST + 1,
   1194 				 (ahc->targ_msg_req >> 8) & 0xFF);
   1195 
   1196 			if (!paused)
   1197 				unpause_sequencer(ahc);
   1198 		}
   1199 	}
   1200 }
   1201 
   1202 static void
   1203 ahc_set_syncrate(struct ahc_softc *ahc, struct ahc_devinfo *devinfo,
   1204 		 const struct ahc_syncrate *syncrate,
   1205 		 u_int period, u_int offset, u_int type, int paused, int done)
   1206 {
   1207 	struct	ahc_initiator_tinfo *tinfo;
   1208 	struct	tmode_tstate *tstate;
   1209 	u_int	old_period;
   1210 	u_int	old_offset;
   1211 	int	active = (type & AHC_TRANS_ACTIVE) == AHC_TRANS_ACTIVE;
   1212 
   1213 	if (syncrate == NULL) {
   1214 		period = 0;
   1215 		offset = 0;
   1216 	}
   1217 
   1218 	tinfo = ahc_fetch_transinfo(ahc, devinfo->channel, devinfo->our_scsiid,
   1219 				    devinfo->target, &tstate);
   1220 	old_period = tinfo->current.period;
   1221 	old_offset = tinfo->current.offset;
   1222 
   1223 	if ((type & AHC_TRANS_CUR) != 0
   1224 	 && (old_period != period || old_offset != offset)) {
   1225 		u_int	scsirate;
   1226 
   1227 		scsirate = tinfo->scsirate;
   1228 		if ((ahc->features & AHC_ULTRA2) != 0) {
   1229 
   1230 			/* XXX */
   1231 			/* Force single edge until DT is fully implemented */
   1232 			scsirate &= ~(SXFR_ULTRA2|SINGLE_EDGE|ENABLE_CRC);
   1233 			if (syncrate != NULL)
   1234 				scsirate |= syncrate->sxfr_u2|SINGLE_EDGE;
   1235 
   1236 			if (active)
   1237 				ahc_outb(ahc, SCSIOFFSET, offset);
   1238 		} else {
   1239 
   1240 			scsirate &= ~(SXFR|SOFS);
   1241 			/*
   1242 			 * Ensure Ultra mode is set properly for
   1243 			 * this target.
   1244 			 */
   1245 			tstate->ultraenb &= ~devinfo->target_mask;
   1246 			if (syncrate != NULL) {
   1247 				if (syncrate->sxfr & ULTRA_SXFR) {
   1248 					tstate->ultraenb |=
   1249 						devinfo->target_mask;
   1250 				}
   1251 				scsirate |= syncrate->sxfr & SXFR;
   1252 				scsirate |= offset & SOFS;
   1253 			}
   1254 			if (active) {
   1255 				u_int sxfrctl0;
   1256 
   1257 				sxfrctl0 = ahc_inb(ahc, SXFRCTL0);
   1258 				sxfrctl0 &= ~FAST20;
   1259 				if (tstate->ultraenb & devinfo->target_mask)
   1260 					sxfrctl0 |= FAST20;
   1261 				ahc_outb(ahc, SXFRCTL0, sxfrctl0);
   1262 			}
   1263 		}
   1264 		if (active)
   1265 			ahc_outb(ahc, SCSIRATE, scsirate);
   1266 
   1267 		tinfo->scsirate = scsirate;
   1268 		tinfo->current.period = period;
   1269 		tinfo->current.offset = offset;
   1270 
   1271 		/* Update the syncrates in any pending scbs */
   1272 		ahc_update_pending_syncrates(ahc);
   1273 	}
   1274 
   1275 	if ((type & AHC_TRANS_GOAL) != 0) {
   1276 		tinfo->goal.period = period;
   1277 		tinfo->goal.offset = offset;
   1278 	}
   1279 
   1280 	if ((type & AHC_TRANS_USER) != 0) {
   1281 		tinfo->user.period = period;
   1282 		tinfo->user.offset = offset;
   1283 	}
   1284 
   1285 	ahc_update_target_msg_request(ahc, devinfo, tinfo,
   1286 				      /*force*/FALSE,
   1287 				      paused);
   1288 }
   1289 
   1290 static void
   1291 ahc_set_width(struct ahc_softc *ahc, struct ahc_devinfo *devinfo,
   1292 	      u_int width, u_int type, int paused, int done)
   1293 {
   1294 	struct ahc_initiator_tinfo *tinfo;
   1295 	struct tmode_tstate *tstate;
   1296 	u_int  oldwidth;
   1297 	int    active = (type & AHC_TRANS_ACTIVE) == AHC_TRANS_ACTIVE;
   1298 
   1299 	tinfo = ahc_fetch_transinfo(ahc, devinfo->channel, devinfo->our_scsiid,
   1300 				    devinfo->target, &tstate);
   1301 	oldwidth = tinfo->current.width;
   1302 
   1303 	if ((type & AHC_TRANS_CUR) != 0 && oldwidth != width) {
   1304 		u_int	scsirate;
   1305 
   1306 		scsirate =  tinfo->scsirate;
   1307 		scsirate &= ~WIDEXFER;
   1308 		if (width == MSG_EXT_WDTR_BUS_16_BIT)
   1309 			scsirate |= WIDEXFER;
   1310 
   1311 		tinfo->scsirate = scsirate;
   1312 
   1313 		if (active)
   1314 			ahc_outb(ahc, SCSIRATE, scsirate);
   1315 
   1316 		tinfo->current.width = width;
   1317 	}
   1318 
   1319 	if ((type & AHC_TRANS_GOAL) != 0)
   1320 		tinfo->goal.width = width;
   1321 	if ((type & AHC_TRANS_USER) != 0)
   1322 		tinfo->user.width = width;
   1323 
   1324 	ahc_update_target_msg_request(ahc, devinfo, tinfo,
   1325 				      /*force*/FALSE, paused);
   1326 }
   1327 
   1328 static void
   1329 ahc_set_tags(struct ahc_softc *ahc, struct ahc_devinfo *devinfo, int enable)
   1330 {
   1331 	struct ahc_initiator_tinfo *tinfo;
   1332 	struct tmode_tstate *tstate;
   1333 
   1334 	tinfo = ahc_fetch_transinfo(ahc, devinfo->channel, devinfo->our_scsiid,
   1335 				    devinfo->target, &tstate);
   1336 
   1337 	if (enable) {
   1338 		tstate->tagenable |= devinfo->target_mask;
   1339 	} else {
   1340 		tstate->tagenable &= ~devinfo->target_mask;
   1341 		tstate->tagdisable |= devinfo->target_mask;
   1342 	}
   1343 }
   1344 
   1345 static void
   1346 ahc_update_xfer_mode(struct ahc_softc *ahc, struct ahc_devinfo *devinfo)
   1347 {
   1348 	struct scsipi_xfer_mode xm;
   1349 	struct ahc_initiator_tinfo *tinfo;
   1350 	struct tmode_tstate *tstate;
   1351 
   1352 	if (ahc->inited_targets[devinfo->target] != 2)
   1353 		return;
   1354 
   1355 	tinfo = ahc_fetch_transinfo(ahc, devinfo->channel, devinfo->our_scsiid,
   1356 				    devinfo->target, &tstate);
   1357 
   1358 	xm.xm_target = devinfo->target;
   1359 	xm.xm_mode = 0;
   1360 	xm.xm_period = tinfo->current.period;
   1361 	xm.xm_offset = tinfo->current.offset;
   1362 	if (tinfo->current.width == 1)
   1363 		xm.xm_mode |= PERIPH_CAP_WIDE16;
   1364 	if (tinfo->current.period)
   1365 		xm.xm_mode |= PERIPH_CAP_SYNC;
   1366 	if (tstate->tagenable & devinfo->target_mask)
   1367 		xm.xm_mode |= PERIPH_CAP_TQING;
   1368 	scsipi_async_event(
   1369 	    devinfo->channel == 'B' ? &ahc->sc_channel_b : &ahc->sc_channel,
   1370 	    ASYNC_EVENT_XFER_MODE, &xm);
   1371 }
   1372 
   1373 /*
   1374  * Attach all the sub-devices we can find
   1375  */
   1376 int
   1377 ahc_attach(struct ahc_softc *ahc)
   1378 {
   1379 	ahc->sc_adapter.adapt_dev = &ahc->sc_dev;
   1380 	ahc->sc_adapter.adapt_nchannels = (ahc->features & AHC_TWIN) ? 2 : 1;
   1381 	if (ahc->flags & AHC_PAGESCBS) {
   1382 		ahc->sc_adapter.adapt_openings = AHC_SCB_MAX;
   1383 		ahc->sc_adapter.adapt_max_periph = 16;
   1384 	} else {
   1385 		ahc->sc_adapter.adapt_openings =  ahc->scb_data->maxhscbs;
   1386 		if (ahc->scb_data->maxhscbs >= 16)
   1387 			ahc->sc_adapter.adapt_max_periph = 16;
   1388 		else
   1389 			ahc->sc_adapter.adapt_max_periph = 4;
   1390 	}
   1391 	ahc->sc_adapter.adapt_ioctl = ahc_ioctl;
   1392 	ahc->sc_adapter.adapt_minphys = ahcminphys;
   1393 	ahc->sc_adapter.adapt_request = ahc_action;
   1394 
   1395 	ahc->sc_channel.chan_adapter = &ahc->sc_adapter;
   1396 	ahc->sc_channel.chan_bustype = &scsi_bustype;
   1397 	ahc->sc_channel.chan_channel = 0;
   1398 	ahc->sc_channel.chan_ntargets = (ahc->features & AHC_WIDE) ? 16 : 8;
   1399 	ahc->sc_channel.chan_nluns = 8;
   1400 	ahc->sc_channel.chan_id = ahc->our_id;
   1401 
   1402 	if (ahc->features & AHC_TWIN) {
   1403 		ahc->sc_channel_b = ahc->sc_channel;
   1404 		ahc->sc_channel_b.chan_id = ahc->our_id_b;
   1405 		ahc->sc_channel_b.chan_channel = 1;
   1406 	}
   1407 
   1408 	if ((ahc->flags & AHC_CHANNEL_B_PRIMARY) == 0) {
   1409 		config_found((void *)ahc, &ahc->sc_channel, scsiprint);
   1410 		if (ahc->features & AHC_TWIN)
   1411 			config_found((void *)ahc, &ahc->sc_channel_b,
   1412 			    scsiprint);
   1413 	} else {
   1414 		config_found((void *)ahc, &ahc->sc_channel_b, scsiprint);
   1415 		config_found((void *)ahc, &ahc->sc_channel, scsiprint);
   1416 	}
   1417 	return 1;
   1418 }
   1419 
   1420 static void
   1421 ahc_fetch_devinfo(struct ahc_softc *ahc, struct ahc_devinfo *devinfo)
   1422 {
   1423 	u_int	saved_tcl;
   1424 	role_t	role;
   1425 	int	our_id;
   1426 
   1427 	if (ahc_inb(ahc, SSTAT0) & TARGET)
   1428 		role = ROLE_TARGET;
   1429 	else
   1430 		role = ROLE_INITIATOR;
   1431 
   1432 	if (role == ROLE_TARGET
   1433 	 && (ahc->features & AHC_MULTI_TID) != 0
   1434 	 && (ahc_inb(ahc, SEQ_FLAGS) & CMDPHASE_PENDING) != 0) {
   1435 		/* We were selected, so pull our id from TARGIDIN */
   1436 		our_id = ahc_inb(ahc, TARGIDIN) & OID;
   1437 	} else if ((ahc->features & AHC_ULTRA2) != 0)
   1438 		our_id = ahc_inb(ahc, SCSIID_ULTRA2) & OID;
   1439 	else
   1440 		our_id = ahc_inb(ahc, SCSIID) & OID;
   1441 
   1442 	saved_tcl = ahc_inb(ahc, SAVED_TCL);
   1443 	ahc_compile_devinfo(devinfo, our_id, TCL_TARGET(saved_tcl),
   1444 			    TCL_LUN(saved_tcl), TCL_CHANNEL(ahc, saved_tcl),
   1445 			    role);
   1446 }
   1447 
   1448 static void
   1449 ahc_compile_devinfo(struct ahc_devinfo *devinfo, u_int our_id, u_int target,
   1450 		    u_int lun, char channel, role_t role)
   1451 {
   1452 	devinfo->our_scsiid = our_id;
   1453 	devinfo->target = target;
   1454 	devinfo->lun = lun;
   1455 	devinfo->target_offset = target;
   1456 	devinfo->channel = channel;
   1457 	devinfo->role = role;
   1458 	if (channel == 'B')
   1459 		devinfo->target_offset += 8;
   1460 	devinfo->target_mask = (0x01 << devinfo->target_offset);
   1461 }
   1462 
   1463 /*
   1464  * Catch an interrupt from the adapter
   1465  */
   1466 int
   1467 ahc_intr(void *arg)
   1468 {
   1469 	struct	ahc_softc *ahc;
   1470 	u_int	intstat;
   1471 
   1472 	ahc = (struct ahc_softc *)arg;
   1473 
   1474 	intstat = ahc_inb(ahc, INTSTAT);
   1475 
   1476 	/*
   1477 	 * Any interrupts to process?
   1478 	 */
   1479 	if ((intstat & INT_PEND) == 0) {
   1480 		if (ahc->bus_intr && ahc->bus_intr(ahc)) {
   1481 #ifdef AHC_DEBUG
   1482 			printf("%s: bus intr: CCHADDR %x HADDR %x SEQADDR %x\n",
   1483 			    ahc_name(ahc),
   1484 			    ahc_inb(ahc, CCHADDR) |
   1485 			    (ahc_inb(ahc, CCHADDR+1) << 8)
   1486 			    | (ahc_inb(ahc, CCHADDR+2) << 16)
   1487 			    | (ahc_inb(ahc, CCHADDR+3) << 24),
   1488 			    ahc_inb(ahc, HADDR) | (ahc_inb(ahc, HADDR+1) << 8)
   1489 			    | (ahc_inb(ahc, HADDR+2) << 16)
   1490 			    | (ahc_inb(ahc, HADDR+3) << 24),
   1491 			    ahc_inb(ahc, SEQADDR0) |
   1492 			    (ahc_inb(ahc, SEQADDR1) << 8));
   1493 #endif
   1494 			return 1;
   1495 		}
   1496 		return 0;
   1497 	}
   1498 
   1499 #ifdef AHC_DEBUG
   1500 	if (ahc_debug & AHC_SHOWINTR) {
   1501 		printf("%s: intstat %x\n", ahc_name(ahc), intstat);
   1502 	}
   1503 #endif
   1504 
   1505 	if (intstat & CMDCMPLT) {
   1506 		ahc_outb(ahc, CLRINT, CLRCMDINT);
   1507 		ahc_run_qoutfifo(ahc);
   1508 	}
   1509 	if (intstat & BRKADRINT) {
   1510 		/*
   1511 		 * We upset the sequencer :-(
   1512 		 * Lookup the error message
   1513 		 */
   1514 		int i, error, num_errors;
   1515 
   1516 		error = ahc_inb(ahc, ERROR);
   1517 		num_errors =  sizeof(hard_error)/sizeof(hard_error[0]);
   1518 		for (i = 0; error != 1 && i < num_errors; i++)
   1519 			error >>= 1;
   1520 		panic("%s: brkadrint, %s at seqaddr = 0x%x\n",
   1521 		      ahc_name(ahc), hard_error[i].errmesg,
   1522 		      ahc_inb(ahc, SEQADDR0) |
   1523 		      (ahc_inb(ahc, SEQADDR1) << 8));
   1524 
   1525 		/* Tell everyone that this HBA is no longer available */
   1526 		ahc_abort_scbs(ahc, AHC_TARGET_WILDCARD, ALL_CHANNELS,
   1527 			       AHC_LUN_WILDCARD, SCB_LIST_NULL, ROLE_UNKNOWN,
   1528 			       XS_DRIVER_STUFFUP);
   1529 	}
   1530 	if (intstat & SEQINT)
   1531 		ahc_handle_seqint(ahc, intstat);
   1532 
   1533 	if (intstat & SCSIINT)
   1534 		ahc_handle_scsiint(ahc, intstat);
   1535 
   1536 	return 1;
   1537 }
   1538 
   1539 static struct tmode_tstate *
   1540 ahc_alloc_tstate(struct ahc_softc *ahc, u_int scsi_id, char channel)
   1541 {
   1542 	struct tmode_tstate *master_tstate;
   1543 	struct tmode_tstate *tstate;
   1544 	int i, s;
   1545 
   1546 	master_tstate = ahc->enabled_targets[ahc->our_id];
   1547 	if (channel == 'B') {
   1548 		scsi_id += 8;
   1549 		master_tstate = ahc->enabled_targets[ahc->our_id_b + 8];
   1550 	}
   1551 	if (ahc->enabled_targets[scsi_id] != NULL
   1552 	 && ahc->enabled_targets[scsi_id] != master_tstate)
   1553 		panic("%s: ahc_alloc_tstate - Target already allocated",
   1554 		      ahc_name(ahc));
   1555 	tstate = malloc(sizeof(*tstate), M_DEVBUF, M_NOWAIT);
   1556 	if (tstate == NULL)
   1557 		return (NULL);
   1558 
   1559 	/*
   1560 	 * If we have allocated a master tstate, copy user settings from
   1561 	 * the master tstate (taken from SRAM or the EEPROM) for this
   1562 	 * channel, but reset our current and goal settings to async/narrow
   1563 	 * until an initiator talks to us.
   1564 	 */
   1565 	if (master_tstate != NULL) {
   1566 		memcpy(tstate, master_tstate, sizeof(*tstate));
   1567 		tstate->ultraenb = 0;
   1568 		for (i = 0; i < 16; i++) {
   1569 			memset(&tstate->transinfo[i].current, 0,
   1570 			      sizeof(tstate->transinfo[i].current));
   1571 			memset(&tstate->transinfo[i].goal, 0,
   1572 			      sizeof(tstate->transinfo[i].goal));
   1573 		}
   1574 	} else
   1575 		memset(tstate, 0, sizeof(*tstate));
   1576 	s = splbio();
   1577 	ahc->enabled_targets[scsi_id] = tstate;
   1578 	splx(s);
   1579 	return (tstate);
   1580 }
   1581 
   1582 #if UNUSED
   1583 static void
   1584 ahc_free_tstate(struct ahc_softc *ahc, u_int scsi_id, char channel, int force)
   1585 {
   1586 	struct tmode_tstate *tstate;
   1587 
   1588 	/* Don't clean up the entry for our initiator role */
   1589 	if ((ahc->flags & AHC_INITIATORMODE) != 0
   1590 	 && ((channel == 'B' && scsi_id == ahc->our_id_b)
   1591 	  || (channel == 'A' && scsi_id == ahc->our_id))
   1592 	 && force == FALSE)
   1593 		return;
   1594 
   1595 	if (channel == 'B')
   1596 		scsi_id += 8;
   1597 	tstate = ahc->enabled_targets[scsi_id];
   1598 	if (tstate != NULL)
   1599 		free(tstate, M_DEVBUF);
   1600 	ahc->enabled_targets[scsi_id] = NULL;
   1601 }
   1602 #endif
   1603 
   1604 static void
   1605 ahc_handle_seqint(struct ahc_softc *ahc, u_int intstat)
   1606 {
   1607 	struct scb *scb;
   1608 	struct ahc_devinfo devinfo;
   1609 
   1610 	ahc_fetch_devinfo(ahc, &devinfo);
   1611 
   1612 	/*
   1613 	 * Clear the upper byte that holds SEQINT status
   1614 	 * codes and clear the SEQINT bit. We will unpause
   1615 	 * the sequencer, if appropriate, after servicing
   1616 	 * the request.
   1617 	 */
   1618 	ahc_outb(ahc, CLRINT, CLRSEQINT);
   1619 	switch (intstat & SEQINT_MASK) {
   1620 	case NO_MATCH:
   1621 	{
   1622 		/* Ensure we don't leave the selection hardware on */
   1623 		ahc_outb(ahc, SCSISEQ,
   1624 			 ahc_inb(ahc, SCSISEQ) & (ENSELI|ENRSELI|ENAUTOATNP));
   1625 
   1626 		printf("%s:%c:%d: no active SCB for reconnecting "
   1627 		       "target - issuing BUS DEVICE RESET\n",
   1628 		       ahc_name(ahc), devinfo.channel, devinfo.target);
   1629 		printf("SAVED_TCL == 0x%x, ARG_1 == 0x%x, SEQ_FLAGS == 0x%x\n",
   1630 		       ahc_inb(ahc, SAVED_TCL), ahc_inb(ahc, ARG_1),
   1631 		       ahc_inb(ahc, SEQ_FLAGS));
   1632 		ahc->msgout_buf[0] = MSG_BUS_DEV_RESET;
   1633 		ahc->msgout_len = 1;
   1634 		ahc->msgout_index = 0;
   1635 		ahc->msg_type = MSG_TYPE_INITIATOR_MSGOUT;
   1636 		ahc_outb(ahc, MSG_OUT, HOST_MSG);
   1637 		ahc_outb(ahc, SCSISIGO, ahc_inb(ahc, LASTPHASE) | ATNO);
   1638 		break;
   1639 	}
   1640 	case UPDATE_TMSG_REQ:
   1641 		ahc_outb(ahc, TARGET_MSG_REQUEST, ahc->targ_msg_req & 0xFF);
   1642 		ahc_outb(ahc, TARGET_MSG_REQUEST + 1,
   1643 			 (ahc->targ_msg_req >> 8) & 0xFF);
   1644 		ahc_outb(ahc, HS_MAILBOX, 0);
   1645 		break;
   1646 	case SEND_REJECT:
   1647 	{
   1648 		u_int rejbyte = ahc_inb(ahc, ACCUM);
   1649 		printf("%s:%c:%d: Warning - unknown message received from "
   1650 		       "target (0x%x).  Rejecting\n",
   1651 		       ahc_name(ahc), devinfo.channel, devinfo.target, rejbyte);
   1652 		break;
   1653 	}
   1654 	case NO_IDENT:
   1655 	{
   1656 		/*
   1657 		 * The reconnecting target either did not send an identify
   1658 		 * message, or did, but we didn't find and SCB to match and
   1659 		 * before it could respond to our ATN/abort, it hit a dataphase.
   1660 		 * The only safe thing to do is to blow it away with a bus
   1661 		 * reset.
   1662 		 */
   1663 		int found;
   1664 
   1665 		printf("%s:%c:%d: Target did not send an IDENTIFY message. "
   1666 		       "LASTPHASE = 0x%x, SAVED_TCL == 0x%x\n",
   1667 		       ahc_name(ahc), devinfo.channel, devinfo.target,
   1668 		       ahc_inb(ahc, LASTPHASE), ahc_inb(ahc, SAVED_TCL));
   1669 		found = ahc_reset_channel(ahc, devinfo.channel,
   1670 					  /*initiate reset*/TRUE);
   1671 		printf("%s: Issued Channel %c Bus Reset. "
   1672 		       "%d SCBs aborted\n", ahc_name(ahc), devinfo.channel,
   1673 		       found);
   1674 		return;
   1675 	}
   1676 	case BAD_PHASE:
   1677 	{
   1678 		u_int lastphase;
   1679 
   1680 		lastphase = ahc_inb(ahc, LASTPHASE);
   1681 		if (lastphase == P_BUSFREE) {
   1682 			printf("%s:%c:%d: Missed busfree.  Curphase = 0x%x\n",
   1683 			       ahc_name(ahc), devinfo.channel, devinfo.target,
   1684 			       ahc_inb(ahc, SCSISIGI));
   1685 			restart_sequencer(ahc);
   1686 			return;
   1687 		} else {
   1688 			printf("%s:%c:%d: unknown scsi bus phase %x.  "
   1689 			       "Attempting to continue\n",
   1690 			       ahc_name(ahc), devinfo.channel, devinfo.target,
   1691 			       ahc_inb(ahc, SCSISIGI));
   1692 		}
   1693 		break;
   1694 	}
   1695 	case BAD_STATUS:
   1696 	{
   1697 		u_int  scb_index;
   1698 		struct hardware_scb *hscb;
   1699 		struct scsipi_xfer *xs;
   1700 		/*
   1701 		 * The sequencer will notify us when a command
   1702 		 * has an error that would be of interest to
   1703 		 * the kernel.  This allows us to leave the sequencer
   1704 		 * running in the common case of command completes
   1705 		 * without error.  The sequencer will already have
   1706 		 * dma'd the SCB back up to us, so we can reference
   1707 		 * the in kernel copy directly.
   1708 		 */
   1709 		scb_index = ahc_inb(ahc, SCB_TAG);
   1710 		scb = &ahc->scb_data->scbarray[scb_index];
   1711 
   1712 		/* ahc_print_scb(scb); */
   1713 
   1714 		/*
   1715 		 * Set the default return value to 0 (don't
   1716 		 * send sense).  The sense code will change
   1717 		 * this if needed.
   1718 		 */
   1719 		ahc_outb(ahc, RETURN_1, 0);
   1720 		if (!(scb_index < ahc->scb_data->numscbs
   1721 		   && (scb->flags & SCB_ACTIVE) != 0)) {
   1722 			printf("%s:%c:%d: ahc_intr - referenced scb "
   1723 			       "not valid during seqint 0x%x scb(%d)\n",
   1724 			       ahc_name(ahc), devinfo.channel,
   1725 			       devinfo.target, intstat, scb_index);
   1726 			goto unpause;
   1727 		}
   1728 
   1729 		hscb = scb->hscb;
   1730 		xs = scb->xs;
   1731 
   1732 		/* Don't want to clobber the original sense code */
   1733 		if ((scb->flags & SCB_SENSE) != 0) {
   1734 			/*
   1735 			 * Clear the SCB_SENSE Flag and have
   1736 			 * the sequencer do a normal command
   1737 			 * complete.
   1738 			 */
   1739 			scb->flags &= ~SCB_SENSE;
   1740 			ahcsetccbstatus(xs, XS_DRIVER_STUFFUP);
   1741 			break;
   1742 		}
   1743 		/* Freeze the queue unit the client sees the error. */
   1744 		ahc_freeze_devq(ahc, xs->xs_periph);
   1745 		ahc_freeze_ccb(scb);
   1746 		xs->status = hscb->status;
   1747 		switch (hscb->status) {
   1748 		case SCSI_STATUS_OK:
   1749 			printf("%s: Interrupted for status of 0???\n",
   1750 			       ahc_name(ahc));
   1751 			break;
   1752 		case SCSI_STATUS_CMD_TERMINATED:
   1753 		case SCSI_STATUS_CHECK_COND:
   1754 #if defined(AHC_DEBUG)
   1755 			if (ahc_debug & AHC_SHOWSENSE) {
   1756 				scsipi_printaddr(xs->xs_periph);
   1757 				printf("Check Status, resid %d datalen %d\n",
   1758 				    xs->resid, xs->datalen);
   1759 			}
   1760 #endif
   1761 
   1762 			if (xs->error == XS_NOERROR &&
   1763 			    !(scb->flags & SCB_SENSE)) {
   1764 				struct ahc_dma_seg *sg;
   1765 				struct scsipi_sense *sc;
   1766 				struct ahc_initiator_tinfo *tinfo;
   1767 				struct tmode_tstate *tstate;
   1768 
   1769 				sg = scb->sg_list;
   1770 				sc = (struct scsipi_sense *)(&hscb->cmdstore);
   1771 				/*
   1772 				 * Save off the residual if there is one.
   1773 				 */
   1774 				if (hscb->residual_SG_count != 0)
   1775 					ahc_calc_residual(scb);
   1776 				else
   1777 					xs->resid = 0;
   1778 
   1779 #ifdef AHC_DEBUG
   1780 				if (ahc_debug & AHC_SHOWSENSE) {
   1781 					scsipi_printaddr(xs->xs_periph);
   1782 					printf("Sending Sense\n");
   1783 				}
   1784 #endif
   1785 				sg->addr = ahc->scb_data->sense_busaddr +
   1786 				   (hscb->tag*sizeof(struct scsipi_sense_data));
   1787 				sg->len = sizeof (struct scsipi_sense_data);
   1788 
   1789 				sc->opcode = REQUEST_SENSE;
   1790 				sc->byte2 =  SCB_LUN(scb) << 5;
   1791 				sc->unused[0] = 0;
   1792 				sc->unused[1] = 0;
   1793 				sc->length = sg->len;
   1794 				sc->control = 0;
   1795 
   1796 				/*
   1797 				 * Would be nice to preserve DISCENB here,
   1798 				 * but due to the way we page SCBs, we can't.
   1799 				 */
   1800 				hscb->control = 0;
   1801 
   1802 				/*
   1803 				 * This request sense could be because the
   1804 				 * the device lost power or in some other
   1805 				 * way has lost our transfer negotiations.
   1806 				 * Renegotiate if appropriate.  Unit attention
   1807 				 * errors will be reported before any data
   1808 				 * phases occur.
   1809 				 */
   1810 				ahc_calc_residual(scb);
   1811 #if defined(AHC_DEBUG)
   1812 				if (ahc_debug & AHC_SHOWSENSE) {
   1813 					scsipi_printaddr(xs->xs_periph);
   1814 					printf("Sense: datalen %d resid %d"
   1815 					       "chan %d id %d targ %d\n",
   1816 					    xs->datalen, xs->resid,
   1817 					    devinfo.channel, devinfo.our_scsiid,
   1818 					    devinfo.target);
   1819 				}
   1820 #endif
   1821 				if (xs->datalen > 0 &&
   1822 				    xs->resid == xs->datalen) {
   1823 					tinfo = ahc_fetch_transinfo(ahc,
   1824 							    devinfo.channel,
   1825 							    devinfo.our_scsiid,
   1826 							    devinfo.target,
   1827 							    &tstate);
   1828 					ahc_update_target_msg_request(ahc,
   1829 							      &devinfo,
   1830 							      tinfo,
   1831 							      /*force*/TRUE,
   1832 							      /*paused*/TRUE);
   1833 				}
   1834 				hscb->status = 0;
   1835 				hscb->SG_count = 1;
   1836 				hscb->SG_pointer = scb->sg_list_phys;
   1837 				hscb->data = sg->addr;
   1838 				hscb->datalen = sg->len;
   1839 				hscb->cmdpointer = hscb->cmdstore_busaddr;
   1840 				hscb->cmdlen = sizeof(*sc);
   1841 				scb->sg_count = hscb->SG_count;
   1842 				ahc_swap_hscb(hscb);
   1843 				ahc_swap_sg(scb->sg_list);
   1844 				scb->flags |= SCB_SENSE;
   1845 				/*
   1846 				 * Ensure the target is busy since this
   1847 				 * will be an untagged request.
   1848 				 */
   1849 				ahc_busy_tcl(ahc, scb);
   1850 				ahc_outb(ahc, RETURN_1, SEND_SENSE);
   1851 
   1852 				/*
   1853 				 * Ensure we have enough time to actually
   1854 				 * retrieve the sense.
   1855 				 */
   1856 				if (!(scb->xs->xs_control & XS_CTL_POLL)) {
   1857 					callout_reset(&scb->xs->xs_callout,
   1858 					    5 * hz, ahc_timeout, scb);
   1859 				}
   1860 			}
   1861 			break;
   1862 		case SCSI_STATUS_QUEUE_FULL:
   1863 		case SCSI_STATUS_BUSY:
   1864 			xs->error = XS_BUSY;
   1865 			break;
   1866 		}
   1867 		break;
   1868 	}
   1869 	case TRACE_POINT:
   1870 	{
   1871 		printf("SSTAT2 = 0x%x DFCNTRL = 0x%x\n", ahc_inb(ahc, SSTAT2),
   1872 		       ahc_inb(ahc, DFCNTRL));
   1873 		printf("SSTAT3 = 0x%x DSTATUS = 0x%x\n", ahc_inb(ahc, SSTAT3),
   1874 		       ahc_inb(ahc, DFSTATUS));
   1875 		printf("SSTAT0 = 0x%x, SCB_DATACNT = 0x%x\n",
   1876 		       ahc_inb(ahc, SSTAT0),
   1877 		       ahc_inb(ahc, SCB_DATACNT));
   1878 		break;
   1879 	}
   1880 	case HOST_MSG_LOOP:
   1881 	{
   1882 		/*
   1883 		 * The sequencer has encountered a message phase
   1884 		 * that requires host assistance for completion.
   1885 		 * While handling the message phase(s), we will be
   1886 		 * notified by the sequencer after each byte is
   1887 		 * transfered so we can track bus phases.
   1888 		 *
   1889 		 * If this is the first time we've seen a HOST_MSG_LOOP,
   1890 		 * initialize the state of the host message loop.
   1891 		 */
   1892 		if (ahc->msg_type == MSG_TYPE_NONE) {
   1893 			u_int bus_phase;
   1894 
   1895 			bus_phase = ahc_inb(ahc, SCSISIGI) & PHASE_MASK;
   1896 			if (bus_phase != P_MESGIN
   1897 			 && bus_phase != P_MESGOUT) {
   1898 				printf("ahc_intr: HOST_MSG_LOOP bad "
   1899 				       "phase 0x%x\n",
   1900 				      bus_phase);
   1901 				/*
   1902 				 * Probably transitioned to bus free before
   1903 				 * we got here.  Just punt the message.
   1904 				 */
   1905 				ahc_clear_intstat(ahc);
   1906 				restart_sequencer(ahc);
   1907 			}
   1908 
   1909 			if (devinfo.role == ROLE_INITIATOR) {
   1910 				struct scb *scb;
   1911 				u_int scb_index;
   1912 
   1913 				scb_index = ahc_inb(ahc, SCB_TAG);
   1914 				scb = &ahc->scb_data->scbarray[scb_index];
   1915 
   1916 				if (bus_phase == P_MESGOUT)
   1917 					ahc_setup_initiator_msgout(ahc,
   1918 								   &devinfo,
   1919 								   scb);
   1920 				else {
   1921 					ahc->msg_type =
   1922 					    MSG_TYPE_INITIATOR_MSGIN;
   1923 					ahc->msgin_index = 0;
   1924 				}
   1925 			} else {
   1926 				if (bus_phase == P_MESGOUT) {
   1927 					ahc->msg_type =
   1928 					    MSG_TYPE_TARGET_MSGOUT;
   1929 					ahc->msgin_index = 0;
   1930 				} else
   1931 					/* XXX Ever executed??? */
   1932 					ahc_setup_target_msgin(ahc, &devinfo);
   1933 			}
   1934 		}
   1935 
   1936 		/* Pass a NULL path so that handlers generate their own */
   1937 		ahc_handle_message_phase(ahc, /*path*/NULL);
   1938 		break;
   1939 	}
   1940 	case PERR_DETECTED:
   1941 	{
   1942 		/*
   1943 		 * If we've cleared the parity error interrupt
   1944 		 * but the sequencer still believes that SCSIPERR
   1945 		 * is true, it must be that the parity error is
   1946 		 * for the currently presented byte on the bus,
   1947 		 * and we are not in a phase (data-in) where we will
   1948 		 * eventually ack this byte.  Ack the byte and
   1949 		 * throw it away in the hope that the target will
   1950 		 * take us to message out to deliver the appropriate
   1951 		 * error message.
   1952 		 */
   1953 		if ((intstat & SCSIINT) == 0
   1954 		 && (ahc_inb(ahc, SSTAT1) & SCSIPERR) != 0) {
   1955 			u_int curphase;
   1956 
   1957 			/*
   1958 			 * The hardware will only let you ack bytes
   1959 			 * if the expected phase in SCSISIGO matches
   1960 			 * the current phase.  Make sure this is
   1961 			 * currently the case.
   1962 			 */
   1963 			curphase = ahc_inb(ahc, SCSISIGI) & PHASE_MASK;
   1964 			ahc_outb(ahc, LASTPHASE, curphase);
   1965 			ahc_outb(ahc, SCSISIGO, curphase);
   1966 			ahc_inb(ahc, SCSIDATL);
   1967 		}
   1968 		break;
   1969 	}
   1970 	case DATA_OVERRUN:
   1971 	{
   1972 		/*
   1973 		 * When the sequencer detects an overrun, it
   1974 		 * places the controller in "BITBUCKET" mode
   1975 		 * and allows the target to complete its transfer.
   1976 		 * Unfortunately, none of the counters get updated
   1977 		 * when the controller is in this mode, so we have
   1978 		 * no way of knowing how large the overrun was.
   1979 		 */
   1980 		u_int scbindex = ahc_inb(ahc, SCB_TAG);
   1981 		u_int lastphase = ahc_inb(ahc, LASTPHASE);
   1982 		int i;
   1983 
   1984 		scb = &ahc->scb_data->scbarray[scbindex];
   1985 		for (i = 0; i < num_phases; i++) {
   1986 			if (lastphase == phase_table[i].phase)
   1987 				break;
   1988 		}
   1989 		scsipi_printaddr(scb->xs->xs_periph);
   1990 		printf("data overrun detected %s."
   1991 		       "  Tag == 0x%x.\n",
   1992 		       phase_table[i].phasemsg,
   1993   		       scb->hscb->tag);
   1994 		scsipi_printaddr(scb->xs->xs_periph);
   1995 		printf("%s seen Data Phase.  Length = %d.  NumSGs = %d.\n",
   1996 		       ahc_inb(ahc, SEQ_FLAGS) & DPHASE ? "Have" : "Haven't",
   1997 		       scb->xs->datalen, scb->sg_count);
   1998 		if (scb->sg_count > 0) {
   1999 			for (i = 0; i < scb->sg_count; i++) {
   2000 				printf("sg[%d] - Addr 0x%x : Length %d\n",
   2001 				       i,
   2002 				       le32toh(scb->sg_list[i].addr),
   2003 				       le32toh(scb->sg_list[i].len));
   2004 			}
   2005 		}
   2006 		/*
   2007 		 * Set this and it will take affect when the
   2008 		 * target does a command complete.
   2009 		 */
   2010 		ahc_freeze_devq(ahc, scb->xs->xs_periph);
   2011 		ahcsetccbstatus(scb->xs, XS_DRIVER_STUFFUP);
   2012 		ahc_freeze_ccb(scb);
   2013 		break;
   2014 	}
   2015 	case TRACEPOINT:
   2016 	{
   2017 		printf("TRACEPOINT: RETURN_1 = %d\n", ahc_inb(ahc, RETURN_1));
   2018 		printf("TRACEPOINT: RETURN_2 = %d\n", ahc_inb(ahc, RETURN_2));
   2019 		printf("TRACEPOINT: ARG_1    = %d\n", ahc_inb(ahc, ARG_1));
   2020 		printf("TRACEPOINT: ARG_2    = %d\n", ahc_inb(ahc, ARG_2));
   2021 		printf("TRACEPOINT: CCHADDR =  %x\n",
   2022 		    ahc_inb(ahc, CCHADDR) | (ahc_inb(ahc, CCHADDR+1) << 8)
   2023 		    | (ahc_inb(ahc, CCHADDR+2) << 16)
   2024 		    | (ahc_inb(ahc, CCHADDR+3) << 24));
   2025 #if 0
   2026 		printf("SSTAT1 == 0x%x\n", ahc_inb(ahc, SSTAT1));
   2027 		printf("SSTAT0 == 0x%x\n", ahc_inb(ahc, SSTAT0));
   2028 		printf(", SCSISIGI == 0x%x\n", ahc_inb(ahc, SCSISIGI));
   2029 		printf("TRACEPOINT: CCHCNT = %d, SG_COUNT = %d\n",
   2030 		       ahc_inb(ahc, CCHCNT), ahc_inb(ahc, SG_COUNT));
   2031 		printf("TRACEPOINT: SCB_TAG = %d\n", ahc_inb(ahc, SCB_TAG));
   2032 		printf("TRACEPOINT1: CCHADDR = %d, CCHCNT = %d, SCBPTR = %d\n",
   2033 		       ahc_inb(ahc, CCHADDR)
   2034 		    | (ahc_inb(ahc, CCHADDR+1) << 8)
   2035 		    | (ahc_inb(ahc, CCHADDR+2) << 16)
   2036 		    | (ahc_inb(ahc, CCHADDR+3) << 24),
   2037 		       ahc_inb(ahc, CCHCNT)
   2038 		    | (ahc_inb(ahc, CCHCNT+1) << 8)
   2039 		    | (ahc_inb(ahc, CCHCNT+2) << 16),
   2040 		       ahc_inb(ahc, SCBPTR));
   2041 		printf("TRACEPOINT: WAITING_SCBH = %d\n", ahc_inb(ahc, WAITING_SCBH));
   2042 		printf("TRACEPOINT: SCB_TAG = %d\n", ahc_inb(ahc, SCB_TAG));
   2043 #if DDB > 0
   2044 		cpu_Debugger();
   2045 #endif
   2046 #endif
   2047 		break;
   2048 	}
   2049 #if NOT_YET
   2050 	/* XXX Fill these in later */
   2051 	case MESG_BUFFER_BUSY:
   2052 		break;
   2053 	case MSGIN_PHASEMIS:
   2054 		break;
   2055 #endif
   2056 	default:
   2057 		printf("ahc_intr: seqint, "
   2058 		       "intstat == 0x%x, scsisigi = 0x%x\n",
   2059 		       intstat, ahc_inb(ahc, SCSISIGI));
   2060 		break;
   2061 	}
   2062 
   2063 unpause:
   2064 	/*
   2065 	 *  The sequencer is paused immediately on
   2066 	 *  a SEQINT, so we should restart it when
   2067 	 *  we're done.
   2068 	 */
   2069 	unpause_sequencer(ahc);
   2070 }
   2071 
   2072 static void
   2073 ahc_handle_scsiint(struct ahc_softc *ahc, u_int intstat)
   2074 {
   2075 	u_int	scb_index;
   2076 	u_int	status;
   2077 	struct	scb *scb;
   2078 	char	cur_channel;
   2079 	char	intr_channel;
   2080 
   2081 	if ((ahc->features & AHC_TWIN) != 0
   2082 	 && ((ahc_inb(ahc, SBLKCTL) & SELBUSB) != 0))
   2083 		cur_channel = 'B';
   2084 	else
   2085 		cur_channel = 'A';
   2086 	intr_channel = cur_channel;
   2087 
   2088 	status = ahc_inb(ahc, SSTAT1);
   2089 	if (status == 0) {
   2090 		if ((ahc->features & AHC_TWIN) != 0) {
   2091 			/* Try the other channel */
   2092 		 	ahc_outb(ahc, SBLKCTL, ahc_inb(ahc, SBLKCTL) ^ SELBUSB);
   2093 			status = ahc_inb(ahc, SSTAT1);
   2094 		 	ahc_outb(ahc, SBLKCTL, ahc_inb(ahc, SBLKCTL) ^ SELBUSB);
   2095 			intr_channel = (cur_channel == 'A') ? 'B' : 'A';
   2096 		}
   2097 		if (status == 0) {
   2098 			printf("%s: Spurious SCSI interrupt\n", ahc_name(ahc));
   2099 			return;
   2100 		}
   2101 	}
   2102 
   2103 	scb_index = ahc_inb(ahc, SCB_TAG);
   2104 	if (scb_index < ahc->scb_data->numscbs) {
   2105 		scb = &ahc->scb_data->scbarray[scb_index];
   2106 		if ((scb->flags & SCB_ACTIVE) == 0
   2107 		 || (ahc_inb(ahc, SEQ_FLAGS) & IDENTIFY_SEEN) == 0)
   2108 			scb = NULL;
   2109 	} else
   2110 		scb = NULL;
   2111 
   2112 	if ((status & SCSIRSTI) != 0) {
   2113 		printf("%s: Someone reset channel %c\n",
   2114 			ahc_name(ahc), intr_channel);
   2115 		ahc_reset_channel(ahc, intr_channel, /* Initiate Reset */FALSE);
   2116 	} else if ((status & SCSIPERR) != 0) {
   2117 		/*
   2118 		 * Determine the bus phase and queue an appropriate message.
   2119 		 * SCSIPERR is latched true as soon as a parity error
   2120 		 * occurs.  If the sequencer acked the transfer that
   2121 		 * caused the parity error and the currently presented
   2122 		 * transfer on the bus has correct parity, SCSIPERR will
   2123 		 * be cleared by CLRSCSIPERR.  Use this to determine if
   2124 		 * we should look at the last phase the sequencer recorded,
   2125 		 * or the current phase presented on the bus.
   2126 		 */
   2127 		u_int mesg_out;
   2128 		u_int curphase;
   2129 		u_int errorphase;
   2130 		u_int lastphase;
   2131 		int   i;
   2132 
   2133 		lastphase = ahc_inb(ahc, LASTPHASE);
   2134 		curphase = ahc_inb(ahc, SCSISIGI) & PHASE_MASK;
   2135 		ahc_outb(ahc, CLRSINT1, CLRSCSIPERR);
   2136 		/*
   2137 		 * For all phases save DATA, the sequencer won't
   2138 		 * automatically ack a byte that has a parity error
   2139 		 * in it.  So the only way that the current phase
   2140 		 * could be 'data-in' is if the parity error is for
   2141 		 * an already acked byte in the data phase.  During
   2142 		 * synchronous data-in transfers, we may actually
   2143 		 * ack bytes before latching the current phase in
   2144 		 * LASTPHASE, leading to the discrepancy between
   2145 		 * curphase and lastphase.
   2146 		 */
   2147 		if ((ahc_inb(ahc, SSTAT1) & SCSIPERR) != 0
   2148 		 || curphase == P_DATAIN)
   2149 			errorphase = curphase;
   2150 		else
   2151 			errorphase = lastphase;
   2152 
   2153 		for (i = 0; i < num_phases; i++) {
   2154 			if (errorphase == phase_table[i].phase)
   2155 				break;
   2156 		}
   2157 		mesg_out = phase_table[i].mesg_out;
   2158 		if (scb != NULL)
   2159 			scsipi_printaddr(scb->xs->xs_periph);
   2160 		else
   2161 			printf("%s:%c:%d: ", ahc_name(ahc),
   2162 			       intr_channel,
   2163 			       TCL_TARGET(ahc_inb(ahc, SAVED_TCL)));
   2164 
   2165 		printf("parity error detected %s. "
   2166 		       "SEQADDR(0x%x) SCSIRATE(0x%x)\n",
   2167 		       phase_table[i].phasemsg,
   2168 		       ahc_inb(ahc, SEQADDR0) | (ahc_inb(ahc, SEQADDR1) << 8),
   2169 		       ahc_inb(ahc, SCSIRATE));
   2170 
   2171 		/*
   2172 		 * We've set the hardware to assert ATN if we
   2173 		 * get a parity error on "in" phases, so all we
   2174 		 * need to do is stuff the message buffer with
   2175 		 * the appropriate message.  "In" phases have set
   2176 		 * mesg_out to something other than MSG_NOP.
   2177 		 */
   2178 		if (mesg_out != MSG_NOOP) {
   2179 			if (ahc->msg_type != MSG_TYPE_NONE)
   2180 				ahc->send_msg_perror = TRUE;
   2181 			else
   2182 				ahc_outb(ahc, MSG_OUT, mesg_out);
   2183 		}
   2184 		ahc_outb(ahc, CLRINT, CLRSCSIINT);
   2185 		unpause_sequencer(ahc);
   2186 	} else if ((status & BUSFREE) != 0
   2187 		&& (ahc_inb(ahc, SIMODE1) & ENBUSFREE) != 0) {
   2188 		/*
   2189 		 * First look at what phase we were last in.
   2190 		 * If its message out, chances are pretty good
   2191 		 * that the busfree was in response to one of
   2192 		 * our abort requests.
   2193 		 */
   2194 		u_int lastphase = ahc_inb(ahc, LASTPHASE);
   2195 		u_int saved_tcl = ahc_inb(ahc, SAVED_TCL);
   2196 		u_int target = TCL_TARGET(saved_tcl);
   2197 		u_int initiator_role_id = TCL_SCSI_ID(ahc, saved_tcl);
   2198 		char channel = TCL_CHANNEL(ahc, saved_tcl);
   2199 		int printerror = 1;
   2200 
   2201 		ahc_outb(ahc, SCSISEQ,
   2202 			 ahc_inb(ahc, SCSISEQ) & (ENSELI|ENRSELI|ENAUTOATNP));
   2203 		if (lastphase == P_MESGOUT) {
   2204 			u_int message;
   2205 			u_int tag;
   2206 
   2207 			message = ahc->msgout_buf[ahc->msgout_index - 1];
   2208 			tag = SCB_LIST_NULL;
   2209 			switch (message) {
   2210 			case MSG_ABORT_TAG:
   2211 				tag = scb->hscb->tag;
   2212 				/* FALLTRHOUGH */
   2213 			case MSG_ABORT:
   2214 				scsipi_printaddr(scb->xs->xs_periph);
   2215 				printf("SCB %x - Abort %s Completed.\n",
   2216 				       scb->hscb->tag, tag == SCB_LIST_NULL ?
   2217 				       "" : "Tag");
   2218 				ahc_abort_scbs(ahc, target, channel,
   2219 					       TCL_LUN(saved_tcl), tag,
   2220 					       ROLE_INITIATOR,
   2221 					       XS_DRIVER_STUFFUP);
   2222 				printerror = 0;
   2223 				break;
   2224 			case MSG_BUS_DEV_RESET:
   2225 			{
   2226 				struct ahc_devinfo devinfo;
   2227 
   2228 				if (scb != NULL &&
   2229 				    (scb->xs->xs_control & XS_CTL_RESET)
   2230 				 && ahc_match_scb(scb, target, channel,
   2231 						  TCL_LUN(saved_tcl),
   2232 						  SCB_LIST_NULL,
   2233 						  ROLE_INITIATOR)) {
   2234 					ahcsetccbstatus(scb->xs, XS_NOERROR);
   2235 				}
   2236 				ahc_compile_devinfo(&devinfo,
   2237 						    initiator_role_id,
   2238 						    target,
   2239 						    TCL_LUN(saved_tcl),
   2240 						    channel,
   2241 						    ROLE_INITIATOR);
   2242 				ahc_handle_devreset(ahc, &devinfo,
   2243 						    XS_RESET,
   2244 						    "Bus Device Reset",
   2245 						    /*verbose_level*/0);
   2246 				printerror = 0;
   2247 				break;
   2248 			}
   2249 			default:
   2250 				break;
   2251 			}
   2252 		}
   2253 		if (printerror != 0) {
   2254 			int i;
   2255 
   2256 			if (scb != NULL) {
   2257 				u_int tag;
   2258 
   2259 				if ((scb->hscb->control & TAG_ENB) != 0)
   2260 					tag = scb->hscb->tag;
   2261 				else
   2262 					tag = SCB_LIST_NULL;
   2263 				ahc_abort_scbs(ahc, target, channel,
   2264 					       SCB_LUN(scb), tag,
   2265 					       ROLE_INITIATOR,
   2266 					       XS_DRIVER_STUFFUP);
   2267 				scsipi_printaddr(scb->xs->xs_periph);
   2268 			} else {
   2269 				/*
   2270 				 * We had not fully identified this connection,
   2271 				 * so we cannot abort anything.
   2272 				 */
   2273 				printf("%s: ", ahc_name(ahc));
   2274 			}
   2275 			for (i = 0; i < num_phases; i++) {
   2276 				if (lastphase == phase_table[i].phase)
   2277 					break;
   2278 			}
   2279 			printf("Unexpected busfree %s\n"
   2280 			       "SEQADDR == 0x%x\n",
   2281 			       phase_table[i].phasemsg, ahc_inb(ahc, SEQADDR0)
   2282 				| (ahc_inb(ahc, SEQADDR1) << 8));
   2283 		}
   2284 		ahc_clear_msg_state(ahc);
   2285 		ahc_outb(ahc, SIMODE1, ahc_inb(ahc, SIMODE1) & ~ENBUSFREE);
   2286 		ahc_outb(ahc, CLRSINT1, CLRBUSFREE|CLRSCSIPERR);
   2287 		ahc_outb(ahc, CLRINT, CLRSCSIINT);
   2288 		restart_sequencer(ahc);
   2289 	} else if ((status & SELTO) != 0) {
   2290 		u_int scbptr;
   2291 
   2292 		scbptr = ahc_inb(ahc, WAITING_SCBH);
   2293 		ahc_outb(ahc, SCBPTR, scbptr);
   2294 		scb_index = ahc_inb(ahc, SCB_TAG);
   2295 
   2296 		if (scb_index < ahc->scb_data->numscbs) {
   2297 			scb = &ahc->scb_data->scbarray[scb_index];
   2298 			if ((scb->flags & SCB_ACTIVE) == 0)
   2299 				scb = NULL;
   2300 		} else
   2301 			scb = NULL;
   2302 
   2303 		if (scb == NULL) {
   2304 			printf("%s: ahc_intr - referenced scb not "
   2305 			       "valid during SELTO scb(%d, %d)\n",
   2306 			       ahc_name(ahc), scbptr, scb_index);
   2307 		} else {
   2308 			u_int tag;
   2309 
   2310 			tag = SCB_LIST_NULL;
   2311 			if ((scb->hscb->control & TAG_ENB) != 0)
   2312 				tag = scb->hscb->tag;
   2313 
   2314 			ahc_abort_scbs(ahc, SCB_TARGET(scb), SCB_CHANNEL(scb),
   2315 				       SCB_LUN(scb), tag,
   2316 				       ROLE_INITIATOR, XS_SELTIMEOUT);
   2317 		}
   2318 		/* Stop the selection */
   2319 		ahc_outb(ahc, SCSISEQ, 0);
   2320 
   2321 		/* No more pending messages */
   2322 		ahc_clear_msg_state(ahc);
   2323 
   2324 		/*
   2325 		 * Although the driver does not care about the
   2326 		 * 'Selection in Progress' status bit, the busy
   2327 		 * LED does.  SELINGO is only cleared by a sucessful
   2328 		 * selection, so we must manually clear it to ensure
   2329 		 * the LED turns off just incase no future successful
   2330 		 * selections occur (e.g. no devices on the bus).
   2331 		 */
   2332 		ahc_outb(ahc, CLRSINT0, CLRSELINGO);
   2333 
   2334 		/* Clear interrupt state */
   2335 		ahc_outb(ahc, CLRSINT1, CLRSELTIMEO|CLRBUSFREE|CLRSCSIPERR);
   2336 		ahc_outb(ahc, CLRINT, CLRSCSIINT);
   2337 		restart_sequencer(ahc);
   2338 	} else {
   2339 		scsipi_printaddr(scb->xs->xs_periph);
   2340 		printf("Unknown SCSIINT. Status = 0x%x\n", status);
   2341 		ahc_outb(ahc, CLRSINT1, status);
   2342 		ahc_outb(ahc, CLRINT, CLRSCSIINT);
   2343 		unpause_sequencer(ahc);
   2344 	}
   2345 }
   2346 
   2347 static void
   2348 ahc_build_transfer_msg(struct ahc_softc *ahc, struct ahc_devinfo *devinfo)
   2349 {
   2350 	/*
   2351 	 * We need to initiate transfer negotiations.
   2352 	 * If our current and goal settings are identical,
   2353 	 * we want to renegotiate due to a check condition.
   2354 	 */
   2355 	struct	ahc_initiator_tinfo *tinfo;
   2356 	struct	tmode_tstate *tstate;
   2357 	int	dowide;
   2358 	int	dosync;
   2359 
   2360 	tinfo = ahc_fetch_transinfo(ahc, devinfo->channel, devinfo->our_scsiid,
   2361 				    devinfo->target, &tstate);
   2362 	dowide = tinfo->current.width != tinfo->goal.width;
   2363 	dosync = tinfo->current.period != tinfo->goal.period;
   2364 
   2365 	if (!dowide && !dosync) {
   2366 		dowide = tinfo->goal.width != MSG_EXT_WDTR_BUS_8_BIT;
   2367 		dosync = tinfo->goal.period != 0;
   2368 	}
   2369 
   2370 	if (dowide) {
   2371 		ahc_construct_wdtr(ahc, tinfo->goal.width);
   2372 	} else if (dosync) {
   2373 		const struct	ahc_syncrate *rate;
   2374 		u_int	period;
   2375 		u_int	offset;
   2376 
   2377 		period = tinfo->goal.period;
   2378 		rate = ahc_devlimited_syncrate(ahc, &period);
   2379 		offset = tinfo->goal.offset;
   2380 		ahc_validate_offset(ahc, rate, &offset,
   2381 				    tinfo->current.width);
   2382 		ahc_construct_sdtr(ahc, period, offset);
   2383 	} else {
   2384 		panic("ahc_intr: AWAITING_MSG for negotiation, "
   2385 		      "but no negotiation needed\n");
   2386 	}
   2387 }
   2388 
   2389 static void
   2390 ahc_setup_initiator_msgout(struct ahc_softc *ahc, struct ahc_devinfo *devinfo,
   2391 			   struct scb *scb)
   2392 {
   2393 	/*
   2394 	 * To facilitate adding multiple messages together,
   2395 	 * each routine should increment the index and len
   2396 	 * variables instead of setting them explicitly.
   2397 	 */
   2398 	ahc->msgout_index = 0;
   2399 	ahc->msgout_len = 0;
   2400 
   2401 	if ((scb->flags & SCB_DEVICE_RESET) == 0
   2402 	 && ahc_inb(ahc, MSG_OUT) == MSG_IDENTIFYFLAG) {
   2403 		u_int identify_msg;
   2404 
   2405 		identify_msg = MSG_IDENTIFYFLAG | SCB_LUN(scb);
   2406 		if ((scb->hscb->control & DISCENB) != 0)
   2407 			identify_msg |= MSG_IDENTIFY_DISCFLAG;
   2408 		ahc->msgout_buf[ahc->msgout_index++] = identify_msg;
   2409 		ahc->msgout_len++;
   2410 
   2411 		if ((scb->hscb->control & TAG_ENB) != 0) {
   2412 			ahc->msgout_buf[ahc->msgout_index++] =
   2413 						scb->xs->xs_tag_type;
   2414 			ahc->msgout_buf[ahc->msgout_index++] = scb->hscb->tag;
   2415 			ahc->msgout_len += 2;
   2416 		}
   2417 	}
   2418 
   2419 	if (scb->flags & SCB_DEVICE_RESET) {
   2420 		ahc->msgout_buf[ahc->msgout_index++] = MSG_BUS_DEV_RESET;
   2421 		ahc->msgout_len++;
   2422 		scsipi_printaddr(scb->xs->xs_periph);
   2423 		printf("Bus Device Reset Message Sent\n");
   2424 	} else if (scb->flags & SCB_ABORT) {
   2425 		if ((scb->hscb->control & TAG_ENB) != 0)
   2426 			ahc->msgout_buf[ahc->msgout_index++] = MSG_ABORT_TAG;
   2427 		else
   2428 			ahc->msgout_buf[ahc->msgout_index++] = MSG_ABORT;
   2429 		ahc->msgout_len++;
   2430 		scsipi_printaddr(scb->xs->xs_periph);
   2431 		printf("Abort Message Sent\n");
   2432 	} else if ((ahc->targ_msg_req & devinfo->target_mask) != 0) {
   2433 		ahc_build_transfer_msg(ahc, devinfo);
   2434 	} else {
   2435 		printf("ahc_intr: AWAITING_MSG for an SCB that "
   2436 		       "does not have a waiting message");
   2437 		panic("SCB = %d, SCB Control = %x, MSG_OUT = %x "
   2438 		      "SCB flags = %x", scb->hscb->tag, scb->hscb->control,
   2439 		      ahc_inb(ahc, MSG_OUT), scb->flags);
   2440 	}
   2441 
   2442 	/*
   2443 	 * Clear the MK_MESSAGE flag from the SCB so we aren't
   2444 	 * asked to send this message again.
   2445 	 */
   2446 	ahc_outb(ahc, SCB_CONTROL, ahc_inb(ahc, SCB_CONTROL) & ~MK_MESSAGE);
   2447 	ahc->msgout_index = 0;
   2448 	ahc->msg_type = MSG_TYPE_INITIATOR_MSGOUT;
   2449 }
   2450 
   2451 static void
   2452 ahc_setup_target_msgin(struct ahc_softc *ahc, struct ahc_devinfo *devinfo)
   2453 {
   2454 	/*
   2455 	 * To facilitate adding multiple messages together,
   2456 	 * each routine should increment the index and len
   2457 	 * variables instead of setting them explicitly.
   2458 	 */
   2459 	ahc->msgout_index = 0;
   2460 	ahc->msgout_len = 0;
   2461 
   2462 	if ((ahc->targ_msg_req & devinfo->target_mask) != 0)
   2463 		ahc_build_transfer_msg(ahc, devinfo);
   2464 	else
   2465 		panic("ahc_intr: AWAITING target message with no message");
   2466 
   2467 	ahc->msgout_index = 0;
   2468 	ahc->msg_type = MSG_TYPE_TARGET_MSGIN;
   2469 }
   2470 
   2471 static int
   2472 ahc_handle_msg_reject(struct ahc_softc *ahc, struct ahc_devinfo *devinfo)
   2473 {
   2474 	/*
   2475 	 * What we care about here is if we had an
   2476 	 * outstanding SDTR or WDTR message for this
   2477 	 * target.  If we did, this is a signal that
   2478 	 * the target is refusing negotiation.
   2479 	 */
   2480 	struct scb *scb;
   2481 	u_int scb_index;
   2482 	u_int last_msg;
   2483 	int   response = 0;
   2484 
   2485 	scb_index = ahc_inb(ahc, SCB_TAG);
   2486 	scb = &ahc->scb_data->scbarray[scb_index];
   2487 
   2488 	/* Might be necessary */
   2489 	last_msg = ahc_inb(ahc, LAST_MSG);
   2490 
   2491 	if (ahc_sent_msg(ahc, MSG_EXT_WDTR, /*full*/FALSE)) {
   2492 		struct ahc_initiator_tinfo *tinfo;
   2493 		struct tmode_tstate *tstate;
   2494 
   2495 #ifdef AHC_DEBUG_NEG
   2496 		/* note 8bit xfers */
   2497 		printf("%s:%c:%d: refuses WIDE negotiation.  Using "
   2498 		       "8bit transfers\n", ahc_name(ahc),
   2499 		       devinfo->channel, devinfo->target);
   2500 #endif
   2501 		ahc_set_width(ahc, devinfo,
   2502 			      MSG_EXT_WDTR_BUS_8_BIT,
   2503 			      AHC_TRANS_ACTIVE|AHC_TRANS_GOAL,
   2504 			      /*paused*/TRUE, /*done*/TRUE);
   2505 		/*
   2506 		 * No need to clear the sync rate.  If the target
   2507 		 * did not accept the command, our syncrate is
   2508 		 * unaffected.  If the target started the negotiation,
   2509 		 * but rejected our response, we already cleared the
   2510 		 * sync rate before sending our WDTR.
   2511 		 */
   2512 		tinfo = ahc_fetch_transinfo(ahc, devinfo->channel,
   2513 					    devinfo->our_scsiid,
   2514 					    devinfo->target, &tstate);
   2515 		if (tinfo->goal.period) {
   2516 			u_int period;
   2517 
   2518 			/* Start the sync negotiation */
   2519 			period = tinfo->goal.period;
   2520 			ahc_devlimited_syncrate(ahc, &period);
   2521 			ahc->msgout_index = 0;
   2522 			ahc->msgout_len = 0;
   2523 			ahc_construct_sdtr(ahc, period, tinfo->goal.offset);
   2524 			ahc->msgout_index = 0;
   2525 			response = 1;
   2526 		} else
   2527 			ahc_update_xfer_mode(ahc, devinfo);
   2528 	} else if (ahc_sent_msg(ahc, MSG_EXT_SDTR, /*full*/FALSE)) {
   2529 		/* note asynch xfers and clear flag */
   2530 		ahc_set_syncrate(ahc, devinfo, /*syncrate*/NULL, /*period*/0,
   2531 				 /*offset*/0, AHC_TRANS_ACTIVE|AHC_TRANS_GOAL,
   2532 				 /*paused*/TRUE, /*done*/TRUE);
   2533 #ifdef AHC_DEBUG_NEG
   2534 		printf("%s:%c:%d: refuses synchronous negotiation. "
   2535 		       "Using asynchronous transfers\n",
   2536 		       ahc_name(ahc),
   2537 		       devinfo->channel, devinfo->target);
   2538 #endif
   2539 		ahc_update_xfer_mode(ahc, devinfo);
   2540 	} else if ((scb->hscb->control & TAG_ENB) != 0) {
   2541 		printf("%s:%c:%d: refuses tagged commands.  Performing "
   2542 		       "non-tagged I/O\n", ahc_name(ahc),
   2543 		       devinfo->channel, devinfo->target);
   2544 
   2545 		ahc_set_tags(ahc, devinfo, FALSE);
   2546 		ahc_update_xfer_mode(ahc, devinfo);
   2547 
   2548 		/*
   2549 		 * Resend the identify for this CCB as the target
   2550 		 * may believe that the selection is invalid otherwise.
   2551 		 */
   2552 		ahc_outb(ahc, SCB_CONTROL, ahc_inb(ahc, SCB_CONTROL)
   2553 					  & ~MSG_SIMPLE_Q_TAG);
   2554 	 	scb->hscb->control &= ~MSG_SIMPLE_Q_TAG;
   2555 		ahc_outb(ahc, MSG_OUT, MSG_IDENTIFYFLAG);
   2556 		ahc_outb(ahc, SCSISIGO, ahc_inb(ahc, SCSISIGO) | ATNO);
   2557 
   2558 		/*
   2559 		 * Requeue all tagged commands for this target
   2560 		 * currently in our posession so they can be
   2561 		 * converted to untagged commands.
   2562 		 */
   2563 		ahc_search_qinfifo(ahc, SCB_TARGET(scb), SCB_CHANNEL(scb),
   2564 				   SCB_LUN(scb), /*tag*/SCB_LIST_NULL,
   2565 				   ROLE_INITIATOR, SCB_REQUEUE,
   2566 				   SEARCH_COMPLETE);
   2567 	} else {
   2568 		/*
   2569 		 * Otherwise, we ignore it.
   2570 		 */
   2571 		printf("%s:%c:%d: Message reject for %x -- ignored\n",
   2572 		       ahc_name(ahc), devinfo->channel, devinfo->target,
   2573 		       last_msg);
   2574 	}
   2575 	return (response);
   2576 }
   2577 
   2578 static void
   2579 ahc_clear_msg_state(struct ahc_softc *ahc)
   2580 {
   2581 	ahc->msgout_len = 0;
   2582 	ahc->msgin_index = 0;
   2583 	ahc->msg_type = MSG_TYPE_NONE;
   2584 	ahc_outb(ahc, MSG_OUT, MSG_NOOP);
   2585 }
   2586 
   2587 static void
   2588 ahc_handle_message_phase(struct ahc_softc *ahc, struct scsipi_periph *periph)
   2589 {
   2590 	struct	ahc_devinfo devinfo;
   2591 	u_int	bus_phase;
   2592 	int	end_session;
   2593 
   2594 	ahc_fetch_devinfo(ahc, &devinfo);
   2595 	end_session = FALSE;
   2596 	bus_phase = ahc_inb(ahc, SCSISIGI) & PHASE_MASK;
   2597 
   2598 reswitch:
   2599 	switch (ahc->msg_type) {
   2600 	case MSG_TYPE_INITIATOR_MSGOUT:
   2601 	{
   2602 		int lastbyte;
   2603 		int phasemis;
   2604 		int msgdone;
   2605 
   2606 		if (ahc->msgout_len == 0)
   2607 			panic("REQINIT interrupt with no active message");
   2608 
   2609 		phasemis = bus_phase != P_MESGOUT;
   2610 		if (phasemis) {
   2611 			if (bus_phase == P_MESGIN) {
   2612 				/*
   2613 				 * Change gears and see if
   2614 				 * this messages is of interest to
   2615 				 * us or should be passed back to
   2616 				 * the sequencer.
   2617 				 */
   2618 				ahc_outb(ahc, CLRSINT1, CLRATNO);
   2619 				ahc->send_msg_perror = FALSE;
   2620 				ahc->msg_type = MSG_TYPE_INITIATOR_MSGIN;
   2621 				ahc->msgin_index = 0;
   2622 				goto reswitch;
   2623 			}
   2624 			end_session = TRUE;
   2625 			break;
   2626 		}
   2627 
   2628 		if (ahc->send_msg_perror) {
   2629 			ahc_outb(ahc, CLRSINT1, CLRATNO);
   2630 			ahc_outb(ahc, CLRSINT1, CLRREQINIT);
   2631 			ahc_outb(ahc, SCSIDATL, MSG_PARITY_ERROR);
   2632 			break;
   2633 		}
   2634 
   2635 		msgdone	= ahc->msgout_index == ahc->msgout_len;
   2636 		if (msgdone) {
   2637 			/*
   2638 			 * The target has requested a retry.
   2639 			 * Re-assert ATN, reset our message index to
   2640 			 * 0, and try again.
   2641 			 */
   2642 			ahc->msgout_index = 0;
   2643 			ahc_outb(ahc, SCSISIGO, ahc_inb(ahc, SCSISIGO) | ATNO);
   2644 		}
   2645 
   2646 		lastbyte = ahc->msgout_index == (ahc->msgout_len - 1);
   2647 		if (lastbyte) {
   2648 			/* Last byte is signified by dropping ATN */
   2649 			ahc_outb(ahc, CLRSINT1, CLRATNO);
   2650 		}
   2651 
   2652 		/*
   2653 		 * Clear our interrupt status and present
   2654 		 * the next byte on the bus.
   2655 		 */
   2656 		ahc_outb(ahc, CLRSINT1, CLRREQINIT);
   2657 		ahc_outb(ahc, SCSIDATL, ahc->msgout_buf[ahc->msgout_index++]);
   2658 		break;
   2659 	}
   2660 	case MSG_TYPE_INITIATOR_MSGIN:
   2661 	{
   2662 		int phasemis;
   2663 		int message_done;
   2664 
   2665 		phasemis = bus_phase != P_MESGIN;
   2666 
   2667 		if (phasemis) {
   2668 			ahc->msgin_index = 0;
   2669 			if (bus_phase == P_MESGOUT
   2670 			 && (ahc->send_msg_perror == TRUE
   2671 			  || (ahc->msgout_len != 0
   2672 			   && ahc->msgout_index == 0))) {
   2673 				ahc->msg_type = MSG_TYPE_INITIATOR_MSGOUT;
   2674 				goto reswitch;
   2675 			}
   2676 			end_session = TRUE;
   2677 			break;
   2678 		}
   2679 
   2680 		/* Pull the byte in without acking it */
   2681 		ahc->msgin_buf[ahc->msgin_index] = ahc_inb(ahc, SCSIBUSL);
   2682 
   2683 		message_done = ahc_parse_msg(ahc, periph, &devinfo);
   2684 
   2685 		if (message_done) {
   2686 			/*
   2687 			 * Clear our incoming message buffer in case there
   2688 			 * is another message following this one.
   2689 			 */
   2690 			ahc->msgin_index = 0;
   2691 
   2692 			/*
   2693 			 * If this message illicited a response,
   2694 			 * assert ATN so the target takes us to the
   2695 			 * message out phase.
   2696 			 */
   2697 			if (ahc->msgout_len != 0)
   2698 				ahc_outb(ahc, SCSISIGO,
   2699 					 ahc_inb(ahc, SCSISIGO) | ATNO);
   2700 		} else
   2701 			ahc->msgin_index++;
   2702 
   2703 		/* Ack the byte */
   2704 		ahc_outb(ahc, CLRSINT1, CLRREQINIT);
   2705 		ahc_inb(ahc, SCSIDATL);
   2706 		break;
   2707 	}
   2708 	case MSG_TYPE_TARGET_MSGIN:
   2709 	{
   2710 		int msgdone;
   2711 		int msgout_request;
   2712 
   2713 		if (ahc->msgout_len == 0)
   2714 			panic("Target MSGIN with no active message");
   2715 
   2716 		/*
   2717 		 * If we interrupted a mesgout session, the initiator
   2718 		 * will not know this until our first REQ.  So, we
   2719 		 * only honor mesgout requests after we've sent our
   2720 		 * first byte.
   2721 		 */
   2722 		if ((ahc_inb(ahc, SCSISIGI) & ATNI) != 0
   2723 		 && ahc->msgout_index > 0)
   2724 			msgout_request = TRUE;
   2725 		else
   2726 			msgout_request = FALSE;
   2727 
   2728 		if (msgout_request) {
   2729 
   2730 			/*
   2731 			 * Change gears and see if
   2732 			 * this messages is of interest to
   2733 			 * us or should be passed back to
   2734 			 * the sequencer.
   2735 			 */
   2736 			ahc->msg_type = MSG_TYPE_TARGET_MSGOUT;
   2737 			ahc_outb(ahc, SCSISIGO, P_MESGOUT | BSYO);
   2738 			ahc->msgin_index = 0;
   2739 			/* Dummy read to REQ for first byte */
   2740 			ahc_inb(ahc, SCSIDATL);
   2741 			ahc_outb(ahc, SXFRCTL0,
   2742 				 ahc_inb(ahc, SXFRCTL0) | SPIOEN);
   2743 			break;
   2744 		}
   2745 
   2746 		msgdone = ahc->msgout_index == ahc->msgout_len;
   2747 		if (msgdone) {
   2748 			ahc_outb(ahc, SXFRCTL0,
   2749 				 ahc_inb(ahc, SXFRCTL0) & ~SPIOEN);
   2750 			end_session = TRUE;
   2751 			break;
   2752 		}
   2753 
   2754 		/*
   2755 		 * Present the next byte on the bus.
   2756 		 */
   2757 		ahc_outb(ahc, SXFRCTL0, ahc_inb(ahc, SXFRCTL0) | SPIOEN);
   2758 		ahc_outb(ahc, SCSIDATL, ahc->msgout_buf[ahc->msgout_index++]);
   2759 		break;
   2760 	}
   2761 	case MSG_TYPE_TARGET_MSGOUT:
   2762 	{
   2763 		int lastbyte;
   2764 		int msgdone;
   2765 
   2766 		/*
   2767 		 * The initiator signals that this is
   2768 		 * the last byte by dropping ATN.
   2769 		 */
   2770 		lastbyte = (ahc_inb(ahc, SCSISIGI) & ATNI) == 0;
   2771 
   2772 		/*
   2773 		 * Read the latched byte, but turn off SPIOEN first
   2774 		 * so that we don't inadvertantly cause a REQ for the
   2775 		 * next byte.
   2776 		 */
   2777 		ahc_outb(ahc, SXFRCTL0, ahc_inb(ahc, SXFRCTL0) & ~SPIOEN);
   2778 		ahc->msgin_buf[ahc->msgin_index] = ahc_inb(ahc, SCSIDATL);
   2779 		msgdone = ahc_parse_msg(ahc, periph, &devinfo);
   2780 		if (msgdone == MSGLOOP_TERMINATED) {
   2781 			/*
   2782 			 * The message is *really* done in that it caused
   2783 			 * us to go to bus free.  The sequencer has already
   2784 			 * been reset at this point, so pull the ejection
   2785 			 * handle.
   2786 			 */
   2787 			return;
   2788 		}
   2789 
   2790 		ahc->msgin_index++;
   2791 
   2792 		/*
   2793 		 * XXX Read spec about initiator dropping ATN too soon
   2794 		 *     and use msgdone to detect it.
   2795 		 */
   2796 		if (msgdone == MSGLOOP_MSGCOMPLETE) {
   2797 			ahc->msgin_index = 0;
   2798 
   2799 			/*
   2800 			 * If this message illicited a response, transition
   2801 			 * to the Message in phase and send it.
   2802 			 */
   2803 			if (ahc->msgout_len != 0) {
   2804 				ahc_outb(ahc, SCSISIGO, P_MESGIN | BSYO);
   2805 				ahc_outb(ahc, SXFRCTL0,
   2806 					 ahc_inb(ahc, SXFRCTL0) | SPIOEN);
   2807 				ahc->msg_type = MSG_TYPE_TARGET_MSGIN;
   2808 				ahc->msgin_index = 0;
   2809 				break;
   2810 			}
   2811 		}
   2812 
   2813 		if (lastbyte)
   2814 			end_session = TRUE;
   2815 		else {
   2816 			/* Ask for the next byte. */
   2817 			ahc_outb(ahc, SXFRCTL0,
   2818 				 ahc_inb(ahc, SXFRCTL0) | SPIOEN);
   2819 		}
   2820 
   2821 		break;
   2822 	}
   2823 	default:
   2824 		panic("Unknown REQINIT message type");
   2825 	}
   2826 
   2827 	if (end_session) {
   2828 		ahc_clear_msg_state(ahc);
   2829 		ahc_outb(ahc, RETURN_1, EXIT_MSG_LOOP);
   2830 	} else
   2831 		ahc_outb(ahc, RETURN_1, CONT_MSG_LOOP);
   2832 }
   2833 
   2834 /*
   2835  * See if we sent a particular extended message to the target.
   2836  * If "full" is true, the target saw the full message.
   2837  * If "full" is false, the target saw at least the first
   2838  * byte of the message.
   2839  */
   2840 static int
   2841 ahc_sent_msg(struct ahc_softc *ahc, u_int msgtype, int full)
   2842 {
   2843 	int found;
   2844 	int index;
   2845 
   2846 	found = FALSE;
   2847 	index = 0;
   2848 
   2849 	while (index < ahc->msgout_len) {
   2850 		if (ahc->msgout_buf[index] == MSG_EXTENDED) {
   2851 
   2852 			/* Found a candidate */
   2853 			if (ahc->msgout_buf[index+2] == msgtype) {
   2854 				u_int end_index;
   2855 
   2856 				end_index = index + 1
   2857 					  + ahc->msgout_buf[index + 1];
   2858 				if (full) {
   2859 					if (ahc->msgout_index > end_index)
   2860 						found = TRUE;
   2861 				} else if (ahc->msgout_index > index)
   2862 					found = TRUE;
   2863 			}
   2864 			break;
   2865 		} else if (ahc->msgout_buf[index] >= MSG_SIMPLE_Q_TAG
   2866 			&& ahc->msgout_buf[index] <= MSG_IGN_WIDE_RESIDUE) {
   2867 
   2868 			/* Skip tag type and tag id or residue param*/
   2869 			index += 2;
   2870 		} else {
   2871 			/* Single byte message */
   2872 			index++;
   2873 		}
   2874 	}
   2875 	return (found);
   2876 }
   2877 
   2878 static int
   2879 ahc_parse_msg(struct ahc_softc *ahc, struct scsipi_periph *periph,
   2880 	      struct ahc_devinfo *devinfo)
   2881 {
   2882 	struct	ahc_initiator_tinfo *tinfo;
   2883 	struct	tmode_tstate *tstate;
   2884 	int	reject;
   2885 	int	done;
   2886 	int	response;
   2887 	u_int	targ_scsirate;
   2888 
   2889 	done = MSGLOOP_IN_PROG;
   2890 	response = FALSE;
   2891 	reject = FALSE;
   2892 	tinfo = ahc_fetch_transinfo(ahc, devinfo->channel, devinfo->our_scsiid,
   2893 				    devinfo->target, &tstate);
   2894 	targ_scsirate = tinfo->scsirate;
   2895 
   2896 	/*
   2897 	 * Parse as much of the message as is available,
   2898 	 * rejecting it if we don't support it.  When
   2899 	 * the entire message is available and has been
   2900 	 * handled, return MSGLOOP_MSGCOMPLETE, indicating
   2901 	 * that we have parsed an entire message.
   2902 	 *
   2903 	 * In the case of extended messages, we accept the length
   2904 	 * byte outright and perform more checking once we know the
   2905 	 * extended message type.
   2906 	 */
   2907 	switch (ahc->msgin_buf[0]) {
   2908 	case MSG_MESSAGE_REJECT:
   2909 		response = ahc_handle_msg_reject(ahc, devinfo);
   2910 		/* FALLTHROUGH */
   2911 	case MSG_NOOP:
   2912 		done = MSGLOOP_MSGCOMPLETE;
   2913 		break;
   2914 	case MSG_IGN_WIDE_RESIDUE:
   2915 	{
   2916 		/* Wait for the whole message */
   2917 		if (ahc->msgin_index >= 1) {
   2918 			if (ahc->msgin_buf[1] != 1
   2919 			 || tinfo->current.width == MSG_EXT_WDTR_BUS_8_BIT) {
   2920 				reject = TRUE;
   2921 				done = MSGLOOP_MSGCOMPLETE;
   2922 			} else
   2923 				ahc_handle_ign_wide_residue(ahc, devinfo);
   2924 		}
   2925 		break;
   2926 	}
   2927 	case MSG_EXTENDED:
   2928 	{
   2929 		/* Wait for enough of the message to begin validation */
   2930 		if (ahc->msgin_index < 2)
   2931 			break;
   2932 		switch (ahc->msgin_buf[2]) {
   2933 		case MSG_EXT_SDTR:
   2934 		{
   2935 			const struct	 ahc_syncrate *syncrate;
   2936 			u_int	 period;
   2937 			u_int	 offset;
   2938 			u_int	 saved_offset;
   2939 
   2940 			if (ahc->msgin_buf[1] != MSG_EXT_SDTR_LEN) {
   2941 				reject = TRUE;
   2942 				break;
   2943 			}
   2944 
   2945 			/*
   2946 			 * Wait until we have both args before validating
   2947 			 * and acting on this message.
   2948 			 *
   2949 			 * Add one to MSG_EXT_SDTR_LEN to account for
   2950 			 * the extended message preamble.
   2951 			 */
   2952 			if (ahc->msgin_index < (MSG_EXT_SDTR_LEN + 1))
   2953 				break;
   2954 
   2955 			period = ahc->msgin_buf[3];
   2956 			saved_offset = offset = ahc->msgin_buf[4];
   2957 			syncrate = ahc_devlimited_syncrate(ahc, &period);
   2958 			ahc_validate_offset(ahc, syncrate, &offset,
   2959 					    targ_scsirate & WIDEXFER);
   2960 			ahc_set_syncrate(ahc, devinfo,
   2961 					 syncrate, period, offset,
   2962 					 AHC_TRANS_ACTIVE|AHC_TRANS_GOAL,
   2963 					 /*paused*/TRUE, /*done*/TRUE);
   2964 			ahc_update_xfer_mode(ahc, devinfo);
   2965 
   2966 			/*
   2967 			 * See if we initiated Sync Negotiation
   2968 			 * and didn't have to fall down to async
   2969 			 * transfers.
   2970 			 */
   2971 			if (ahc_sent_msg(ahc, MSG_EXT_SDTR, /*full*/TRUE)) {
   2972 				/* We started it */
   2973 				if (saved_offset != offset) {
   2974 					/* Went too low - force async */
   2975 					reject = TRUE;
   2976 				}
   2977 			} else {
   2978 				/*
   2979 				 * Send our own SDTR in reply
   2980 				 */
   2981 				ahc->msgout_index = 0;
   2982 				ahc->msgout_len = 0;
   2983 				ahc_construct_sdtr(ahc, period, offset);
   2984 				ahc->msgout_index = 0;
   2985 				response = TRUE;
   2986 			}
   2987 			done = MSGLOOP_MSGCOMPLETE;
   2988 			break;
   2989 		}
   2990 		case MSG_EXT_WDTR:
   2991 		{
   2992 			u_int	bus_width;
   2993 			u_int	sending_reply;
   2994 
   2995 			sending_reply = FALSE;
   2996 			if (ahc->msgin_buf[1] != MSG_EXT_WDTR_LEN) {
   2997 				reject = TRUE;
   2998 				break;
   2999 			}
   3000 
   3001 			/*
   3002 			 * Wait until we have our arg before validating
   3003 			 * and acting on this message.
   3004 			 *
   3005 			 * Add one to MSG_EXT_WDTR_LEN to account for
   3006 			 * the extended message preamble.
   3007 			 */
   3008 			if (ahc->msgin_index < (MSG_EXT_WDTR_LEN + 1))
   3009 				break;
   3010 
   3011 			bus_width = ahc->msgin_buf[3];
   3012 			if (ahc_sent_msg(ahc, MSG_EXT_WDTR, /*full*/TRUE)) {
   3013 				/*
   3014 				 * Don't send a WDTR back to the
   3015 				 * target, since we asked first.
   3016 				 */
   3017 				switch (bus_width){
   3018 				default:
   3019 					/*
   3020 					 * How can we do anything greater
   3021 					 * than 16bit transfers on a 16bit
   3022 					 * bus?
   3023 					 */
   3024 					reject = TRUE;
   3025 					printf("%s: target %d requested %dBit "
   3026 					       "transfers.  Rejecting...\n",
   3027 					       ahc_name(ahc), devinfo->target,
   3028 					       8 * (0x01 << bus_width));
   3029 					/* FALLTHROUGH */
   3030 				case MSG_EXT_WDTR_BUS_8_BIT:
   3031 					bus_width = MSG_EXT_WDTR_BUS_8_BIT;
   3032 					break;
   3033 				case MSG_EXT_WDTR_BUS_16_BIT:
   3034 					break;
   3035 				}
   3036 			} else {
   3037 				/*
   3038 				 * Send our own WDTR in reply
   3039 				 */
   3040 				switch (bus_width) {
   3041 				default:
   3042 					if (ahc->features & AHC_WIDE) {
   3043 						/* Respond Wide */
   3044 						bus_width =
   3045 						    MSG_EXT_WDTR_BUS_16_BIT;
   3046 						break;
   3047 					}
   3048 					/* FALLTHROUGH */
   3049 				case MSG_EXT_WDTR_BUS_8_BIT:
   3050 					bus_width = MSG_EXT_WDTR_BUS_8_BIT;
   3051 					break;
   3052 				}
   3053 				ahc->msgout_index = 0;
   3054 				ahc->msgout_len = 0;
   3055 				ahc_construct_wdtr(ahc, bus_width);
   3056 				ahc->msgout_index = 0;
   3057 				response = TRUE;
   3058 				sending_reply = TRUE;
   3059 			}
   3060 			ahc_set_width(ahc, devinfo, bus_width,
   3061 				      AHC_TRANS_ACTIVE|AHC_TRANS_GOAL,
   3062 				      /*paused*/TRUE, /*done*/TRUE);
   3063 
   3064 			/* After a wide message, we are async */
   3065 			ahc_set_syncrate(ahc, devinfo,
   3066 					 /*syncrate*/NULL, /*period*/0,
   3067 					 /*offset*/0, AHC_TRANS_ACTIVE,
   3068 					 /*paused*/TRUE, /*done*/FALSE);
   3069 			if (sending_reply == FALSE && reject == FALSE) {
   3070 
   3071 				if (tinfo->goal.period) {
   3072 					const struct	ahc_syncrate *rate;
   3073 					u_int	period;
   3074 					u_int	offset;
   3075 
   3076 					/* Start the sync negotiation */
   3077 					period = tinfo->goal.period;
   3078 					rate = ahc_devlimited_syncrate(ahc,
   3079 								       &period);
   3080 					offset = tinfo->goal.offset;
   3081 					ahc_validate_offset(ahc, rate, &offset,
   3082 							  tinfo->current.width);
   3083 					ahc->msgout_index = 0;
   3084 					ahc->msgout_len = 0;
   3085 					ahc_construct_sdtr(ahc, period, offset);
   3086 					ahc->msgout_index = 0;
   3087 					response = TRUE;
   3088 				} else
   3089 					ahc_update_xfer_mode(ahc, devinfo);
   3090 			}
   3091 			done = MSGLOOP_MSGCOMPLETE;
   3092 			break;
   3093 		}
   3094 		default:
   3095 			/* Unknown extended message.  Reject it. */
   3096 			reject = TRUE;
   3097 			break;
   3098 		}
   3099 		break;
   3100 	}
   3101 	case MSG_BUS_DEV_RESET:
   3102 		ahc_handle_devreset(ahc, devinfo,
   3103 				    XS_RESET, "Bus Device Reset Received",
   3104 				    /*verbose_level*/0);
   3105 		restart_sequencer(ahc);
   3106 		done = MSGLOOP_TERMINATED;
   3107 		break;
   3108 	case MSG_ABORT_TAG:
   3109 	case MSG_ABORT:
   3110 	case MSG_CLEAR_QUEUE:
   3111 		/* Target mode messages */
   3112 		if (devinfo->role != ROLE_TARGET) {
   3113 			reject = TRUE;
   3114 			break;
   3115 		}
   3116 #if AHC_TARGET_MODE
   3117 		ahc_abort_scbs(ahc, devinfo->target, devinfo->channel,
   3118 			       devinfo->lun,
   3119 			       ahc->msgin_buf[0] == MSG_ABORT_TAG
   3120 						  ? SCB_LIST_NULL
   3121 						  : ahc_inb(ahc, INITIATOR_TAG),
   3122 			       ROLE_TARGET, XS_DRIVER_STUFFUP);
   3123 
   3124 		tstate = ahc->enabled_targets[devinfo->our_scsiid];
   3125 		if (tstate != NULL) {
   3126 			struct tmode_lstate* lstate;
   3127 
   3128 			lstate = tstate->enabled_luns[devinfo->lun];
   3129 			if (lstate != NULL) {
   3130 				ahc_queue_lstate_event(ahc, lstate,
   3131 						       devinfo->our_scsiid,
   3132 						       ahc->msgin_buf[0],
   3133 						       /*arg*/0);
   3134 				ahc_send_lstate_events(ahc, lstate);
   3135 			}
   3136 		}
   3137 		done = MSGLOOP_MSGCOMPLETE;
   3138 #else
   3139 		panic("ahc: got target mode message");
   3140 #endif
   3141 		break;
   3142 	case MSG_TERM_IO_PROC:
   3143 	default:
   3144 		reject = TRUE;
   3145 		break;
   3146 	}
   3147 
   3148 	if (reject) {
   3149 		/*
   3150 		 * Setup to reject the message.
   3151 		 */
   3152 		ahc->msgout_index = 0;
   3153 		ahc->msgout_len = 1;
   3154 		ahc->msgout_buf[0] = MSG_MESSAGE_REJECT;
   3155 		done = MSGLOOP_MSGCOMPLETE;
   3156 		response = TRUE;
   3157 	}
   3158 
   3159 	if (done != MSGLOOP_IN_PROG && !response)
   3160 		/* Clear the outgoing message buffer */
   3161 		ahc->msgout_len = 0;
   3162 
   3163 	return (done);
   3164 }
   3165 
   3166 static void
   3167 ahc_handle_ign_wide_residue(struct ahc_softc *ahc, struct ahc_devinfo *devinfo)
   3168 {
   3169 	u_int scb_index;
   3170 	struct scb *scb;
   3171 
   3172 	scb_index = ahc_inb(ahc, SCB_TAG);
   3173 	scb = &ahc->scb_data->scbarray[scb_index];
   3174 	if ((ahc_inb(ahc, SEQ_FLAGS) & DPHASE) == 0
   3175 	 || !(scb->xs->xs_control & XS_CTL_DATA_IN)) {
   3176 		/*
   3177 		 * Ignore the message if we haven't
   3178 		 * seen an appropriate data phase yet.
   3179 		 */
   3180 	} else {
   3181 		/*
   3182 		 * If the residual occurred on the last
   3183 		 * transfer and the transfer request was
   3184 		 * expected to end on an odd count, do
   3185 		 * nothing.  Otherwise, subtract a byte
   3186 		 * and update the residual count accordingly.
   3187 		 */
   3188 		u_int resid_sgcnt;
   3189 
   3190 		resid_sgcnt = ahc_inb(ahc, SCB_RESID_SGCNT);
   3191 		if (resid_sgcnt == 0
   3192 		 && ahc_inb(ahc, DATA_COUNT_ODD) == 1) {
   3193 			/*
   3194 			 * If the residual occurred on the last
   3195 			 * transfer and the transfer request was
   3196 			 * expected to end on an odd count, do
   3197 			 * nothing.
   3198 			 */
   3199 		} else {
   3200 			u_int data_cnt;
   3201 			u_int32_t data_addr;
   3202 			u_int sg_index;
   3203 
   3204 			data_cnt = (ahc_inb(ahc, SCB_RESID_DCNT + 2) << 16)
   3205 				 | (ahc_inb(ahc, SCB_RESID_DCNT + 1) << 8)
   3206 				 | (ahc_inb(ahc, SCB_RESID_DCNT));
   3207 
   3208 			data_addr = (ahc_inb(ahc, SHADDR + 3) << 24)
   3209 				  | (ahc_inb(ahc, SHADDR + 2) << 16)
   3210 				  | (ahc_inb(ahc, SHADDR + 1) << 8)
   3211 				  | (ahc_inb(ahc, SHADDR));
   3212 
   3213 			data_cnt += 1;
   3214 			data_addr -= 1;
   3215 
   3216 			sg_index = scb->sg_count - resid_sgcnt;
   3217 
   3218 			if (sg_index != 0
   3219 			 && (le32toh(scb->sg_list[sg_index].len) < data_cnt)) {
   3220 				u_int32_t sg_addr;
   3221 
   3222 				sg_index--;
   3223 				data_cnt = 1;
   3224 				data_addr = le32toh(scb->sg_list[sg_index].addr)
   3225 					  + le32toh(scb->sg_list[sg_index].len)
   3226 					  - 1;
   3227 
   3228 				/*
   3229 				 * The physical address base points to the
   3230 				 * second entry as it is always used for
   3231 				 * calculating the "next S/G pointer".
   3232 				 */
   3233 				sg_addr = scb->sg_list_phys
   3234 					+ (sg_index* sizeof(*scb->sg_list));
   3235 				ahc_outb(ahc, SG_NEXT + 3, sg_addr >> 24);
   3236 				ahc_outb(ahc, SG_NEXT + 2, sg_addr >> 16);
   3237 				ahc_outb(ahc, SG_NEXT + 1, sg_addr >> 8);
   3238 				ahc_outb(ahc, SG_NEXT, sg_addr);
   3239 			}
   3240 
   3241 			ahc_outb(ahc, SCB_RESID_DCNT + 2, data_cnt >> 16);
   3242 			ahc_outb(ahc, SCB_RESID_DCNT + 1, data_cnt >> 8);
   3243 			ahc_outb(ahc, SCB_RESID_DCNT, data_cnt);
   3244 
   3245 			ahc_outb(ahc, SHADDR + 3, data_addr >> 24);
   3246 			ahc_outb(ahc, SHADDR + 2, data_addr >> 16);
   3247 			ahc_outb(ahc, SHADDR + 1, data_addr >> 8);
   3248 			ahc_outb(ahc, SHADDR, data_addr);
   3249 		}
   3250 	}
   3251 }
   3252 
   3253 static void
   3254 ahc_handle_devreset(struct ahc_softc *ahc, struct ahc_devinfo *devinfo,
   3255 		    int status, char *message,
   3256 		    int verbose_level)
   3257 {
   3258 	int found;
   3259 
   3260 	found = ahc_abort_scbs(ahc, devinfo->target, devinfo->channel,
   3261 			       AHC_LUN_WILDCARD, SCB_LIST_NULL, devinfo->role,
   3262 			       status);
   3263 
   3264 	/*
   3265 	 * Go back to async/narrow transfers and renegotiate.
   3266 	 * ahc_set_width and ahc_set_syncrate can cope with NULL
   3267 	 * paths.
   3268 	 */
   3269 	ahc_set_width(ahc, devinfo, MSG_EXT_WDTR_BUS_8_BIT,
   3270 		      AHC_TRANS_CUR, /*paused*/TRUE, /*done*/FALSE);
   3271 	ahc_set_syncrate(ahc, devinfo, /*syncrate*/NULL,
   3272 			 /*period*/0, /*offset*/0, AHC_TRANS_CUR,
   3273 			 /*paused*/TRUE, /*done*/FALSE);
   3274 	ahc_update_xfer_mode(ahc, devinfo);
   3275 
   3276 	if (message != NULL && (verbose_level <= 0))
   3277 		printf("%s: %s on %c:%d. %d SCBs aborted\n", ahc_name(ahc),
   3278 		       message, devinfo->channel, devinfo->target, found);
   3279 }
   3280 
   3281 /*
   3282  * We have an scb which has been processed by the
   3283  * adaptor, now we look to see how the operation
   3284  * went.
   3285  */
   3286 static void
   3287 ahc_done(struct ahc_softc *ahc, struct scb *scb)
   3288 {
   3289 	struct scsipi_xfer *xs;
   3290 	struct scsipi_periph *periph;
   3291 	int requeue = 0;
   3292 	int target;
   3293 
   3294 
   3295 	xs = scb->xs;
   3296 	periph = xs->xs_periph;
   3297 	LIST_REMOVE(scb, plinks);
   3298 
   3299 	callout_stop(&scb->xs->xs_callout);
   3300 
   3301 #ifdef AHC_DEBUG
   3302 	if (ahc_debug & AHC_SHOWCMDS) {
   3303 		scsipi_printaddr(periph);
   3304 		printf("ahc_done opcode %d tag %x\n", xs->cmdstore.opcode,
   3305 		    scb->hscb->tag);
   3306 	}
   3307 #endif
   3308 
   3309 	target = periph->periph_target;
   3310 
   3311 	if (xs->datalen) {
   3312 		int op;
   3313 
   3314 		if (xs->xs_control & XS_CTL_DATA_IN)
   3315 			op = BUS_DMASYNC_POSTREAD;
   3316 		else
   3317 			op = BUS_DMASYNC_POSTWRITE;
   3318 		bus_dmamap_sync(ahc->parent_dmat, scb->dmamap, 0,
   3319 		    scb->dmamap->dm_mapsize, op);
   3320 		bus_dmamap_unload(ahc->parent_dmat, scb->dmamap);
   3321 	}
   3322 
   3323 	/*
   3324 	 * Unbusy this target/channel/lun.
   3325 	 * XXX if we are holding two commands per lun,
   3326 	 *     send the next command.
   3327 	 */
   3328 	if (!(scb->hscb->control & TAG_ENB))
   3329 		ahc_index_busy_tcl(ahc, scb->hscb->tcl, /*unbusy*/TRUE);
   3330 
   3331 	/*
   3332 	 * If the recovery SCB completes, we have to be
   3333 	 * out of our timeout.
   3334 	 */
   3335 	if ((scb->flags & SCB_RECOVERY_SCB) != 0) {
   3336 
   3337 		struct	scb *scbp;
   3338 
   3339 		/*
   3340 		 * We were able to complete the command successfully,
   3341 		 * so reinstate the timeouts for all other pending
   3342 		 * commands.
   3343 		 */
   3344 		scbp = ahc->pending_ccbs.lh_first;
   3345 		while (scbp != NULL) {
   3346 			struct scsipi_xfer *txs = scbp->xs;
   3347 
   3348 			if (!(txs->xs_control & XS_CTL_POLL)) {
   3349 				callout_reset(&scbp->xs->xs_callout,
   3350 				    (scbp->xs->timeout * hz) / 1000,
   3351 				    ahc_timeout, scbp);
   3352 			}
   3353 			scbp = LIST_NEXT(scbp, plinks);
   3354 		}
   3355 
   3356 		/*
   3357 		 * Ensure that we didn't put a second instance of this
   3358 		 * SCB into the QINFIFO.
   3359 		 */
   3360 		ahc_search_qinfifo(ahc, SCB_TARGET(scb), SCB_CHANNEL(scb),
   3361 				   SCB_LUN(scb), scb->hscb->tag,
   3362 				   ROLE_INITIATOR, /*status*/0,
   3363 				   SEARCH_REMOVE);
   3364 		if (xs->error != XS_NOERROR)
   3365 			ahcsetccbstatus(xs, XS_TIMEOUT);
   3366 		scsipi_printaddr(xs->xs_periph);
   3367 		printf("no longer in timeout, status = %x\n", xs->status);
   3368 	}
   3369 
   3370 	if (xs->error != XS_NOERROR) {
   3371 		/* Don't clobber any existing error state */
   3372 	} else if ((scb->flags & SCB_SENSE) != 0) {
   3373 		/*
   3374 		 * We performed autosense retrieval.
   3375 		 *
   3376 		 * zero the sense data before having
   3377 		 * the drive fill it.  The SCSI spec mandates
   3378 		 * that any untransfered data should be
   3379 		 * assumed to be zero.  Complete the 'bounce'
   3380 		 * of sense information through buffers accessible
   3381 		 * via bus-space by copying it into the clients
   3382 		 * csio.
   3383 		 */
   3384 		memset(&xs->sense.scsi_sense, 0, sizeof(xs->sense.scsi_sense));
   3385 		memcpy(&xs->sense.scsi_sense,
   3386 		    &ahc->scb_data->sense[scb->hscb->tag],
   3387 		    le32toh(scb->sg_list->len));
   3388 		xs->error = XS_SENSE;
   3389 	}
   3390 	if (scb->flags & SCB_FREEZE_QUEUE) {
   3391 		scsipi_periph_thaw(periph, 1);
   3392 		scb->flags &= ~SCB_FREEZE_QUEUE;
   3393 	}
   3394 
   3395 	requeue = scb->flags & SCB_REQUEUE;
   3396 	ahcfreescb(ahc, scb);
   3397 
   3398 	if (requeue) {
   3399 		xs->error = XS_REQUEUE;
   3400 	}
   3401 	scsipi_done(xs);
   3402 }
   3403 
   3404 /*
   3405  * Determine the number of SCBs available on the controller
   3406  */
   3407 int
   3408 ahc_probe_scbs(struct ahc_softc *ahc) {
   3409 	int i;
   3410 
   3411 	for (i = 0; i < AHC_SCB_MAX; i++) {
   3412 		ahc_outb(ahc, SCBPTR, i);
   3413 		ahc_outb(ahc, SCB_CONTROL, i);
   3414 		if (ahc_inb(ahc, SCB_CONTROL) != i)
   3415 			break;
   3416 		ahc_outb(ahc, SCBPTR, 0);
   3417 		if (ahc_inb(ahc, SCB_CONTROL) != 0)
   3418 			break;
   3419 	}
   3420 	return (i);
   3421 }
   3422 
   3423 /*
   3424  * Start the board, ready for normal operation
   3425  */
   3426 int
   3427 ahc_init(struct ahc_softc *ahc)
   3428 {
   3429 	int	  max_targ = 15;
   3430 	int	  i;
   3431 	int	  term;
   3432 	u_int	  scsi_conf;
   3433 	u_int	  scsiseq_template;
   3434 	u_int	  ultraenb;
   3435 	u_int	  discenable;
   3436 	u_int	  tagenable;
   3437 	size_t	  driver_data_size;
   3438 	u_int32_t physaddr;
   3439 
   3440 #ifdef AHC_PRINT_SRAM
   3441 	printf("Scratch Ram:");
   3442 	for (i = 0x20; i < 0x5f; i++) {
   3443 		if (((i % 8) == 0) && (i != 0)) {
   3444 			printf ("\n              ");
   3445 		}
   3446 		printf (" 0x%x", ahc_inb(ahc, i));
   3447 	}
   3448 	if ((ahc->features & AHC_MORE_SRAM) != 0) {
   3449 		for (i = 0x70; i < 0x7f; i++) {
   3450 			if (((i % 8) == 0) && (i != 0)) {
   3451 				printf ("\n              ");
   3452 			}
   3453 			printf (" 0x%x", ahc_inb(ahc, i));
   3454 		}
   3455 	}
   3456 	printf ("\n");
   3457 #endif
   3458 
   3459 	/*
   3460 	 * Assume we have a board at this stage and it has been reset.
   3461 	 */
   3462 	if ((ahc->flags & AHC_USEDEFAULTS) != 0)
   3463 		ahc->our_id = ahc->our_id_b = 7;
   3464 
   3465 	/*
   3466 	 * Default to allowing initiator operations.
   3467 	 */
   3468 	ahc->flags |= AHC_INITIATORMODE;
   3469 
   3470 	/*
   3471 	 * DMA tag for our command fifos and other data in system memory
   3472 	 * the card's sequencer must be able to access.  For initiator
   3473 	 * roles, we need to allocate space for the qinfifo, qoutfifo,
   3474 	 * and untagged_scb arrays each of which are composed of 256
   3475 	 * 1 byte elements.  When providing for the target mode role,
   3476 	 * we additionally must provide space for the incoming target
   3477 	 * command fifo.
   3478 	 */
   3479 	driver_data_size = 3 * 256 * sizeof(u_int8_t);
   3480 
   3481 	if (ahc_createdmamem(ahc->parent_dmat, driver_data_size,
   3482 	    ahc->sc_dmaflags,
   3483 	    &ahc->shared_data_dmamap, (caddr_t *)&ahc->qoutfifo,
   3484 	    &ahc->shared_data_busaddr, &ahc->shared_data_seg,
   3485 	    &ahc->shared_data_nseg, ahc_name(ahc), "shared data") < 0)
   3486 		return (ENOMEM);
   3487 
   3488 	ahc->init_level++;
   3489 
   3490 	/* Allocate SCB data now that parent_dmat is initialized */
   3491 	if (ahc->scb_data->maxhscbs == 0)
   3492 		if (ahcinitscbdata(ahc) != 0)
   3493 			return (ENOMEM);
   3494 
   3495 	ahc->qinfifo = &ahc->qoutfifo[256];
   3496 	ahc->untagged_scbs = &ahc->qinfifo[256];
   3497 	/* There are no untagged SCBs active yet. */
   3498 	for (i = 0; i < 256; i++)
   3499 		ahc->untagged_scbs[i] = SCB_LIST_NULL;
   3500 
   3501 	/* All of our queues are empty */
   3502 	for (i = 0; i < 256; i++)
   3503 		ahc->qoutfifo[i] = SCB_LIST_NULL;
   3504 
   3505 	bus_dmamap_sync(ahc->parent_dmat, ahc->shared_data_dmamap, 0,
   3506 	    driver_data_size, BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
   3507 
   3508 	/*
   3509 	 * Allocate a tstate to house information for our
   3510 	 * initiator presence on the bus as well as the user
   3511 	 * data for any target mode initiator.
   3512 	 */
   3513 	if (ahc_alloc_tstate(ahc, ahc->our_id, 'A') == NULL) {
   3514 		printf("%s: unable to allocate tmode_tstate.  "
   3515 		       "Failing attach\n", ahc_name(ahc));
   3516 		return (-1);
   3517 	}
   3518 
   3519 	if ((ahc->features & AHC_TWIN) != 0) {
   3520 		if (ahc_alloc_tstate(ahc, ahc->our_id_b, 'B') == NULL) {
   3521 			printf("%s: unable to allocate tmode_tstate.  "
   3522 			       "Failing attach\n", ahc_name(ahc));
   3523 			return (-1);
   3524 		}
   3525  		printf("Twin Channel, A SCSI Id=%d, B SCSI Id=%d, primary %c, ",
   3526 		       ahc->our_id, ahc->our_id_b,
   3527 		       ahc->flags & AHC_CHANNEL_B_PRIMARY? 'B': 'A');
   3528 	} else {
   3529 		if ((ahc->features & AHC_WIDE) != 0) {
   3530 			printf("Wide ");
   3531 		} else {
   3532 			printf("Single ");
   3533 		}
   3534 		printf("Channel %c, SCSI Id=%d, ", ahc->channel, ahc->our_id);
   3535 	}
   3536 
   3537 	ahc_outb(ahc, SEQ_FLAGS, 0);
   3538 
   3539 	if (ahc->scb_data->maxhscbs < AHC_SCB_MAX) {
   3540 		ahc->flags |= AHC_PAGESCBS;
   3541 		printf("%d/%d SCBs\n", ahc->scb_data->maxhscbs, AHC_SCB_MAX);
   3542 	} else {
   3543 		ahc->flags &= ~AHC_PAGESCBS;
   3544 		printf("%d SCBs\n", ahc->scb_data->maxhscbs);
   3545 	}
   3546 
   3547 #ifdef AHC_DEBUG
   3548 	if (ahc_debug & AHC_SHOWMISC) {
   3549 		printf("%s: hardware scb %d bytes; kernel scb %d bytes; "
   3550 		       "ahc_dma %d bytes\n",
   3551 			ahc_name(ahc),
   3552 		        sizeof(struct hardware_scb),
   3553 			sizeof(struct scb),
   3554 			sizeof(struct ahc_dma_seg));
   3555 	}
   3556 #endif /* AHC_DEBUG */
   3557 
   3558 	/* Set the SCSI Id, SXFRCTL0, SXFRCTL1, and SIMODE1, for both channels*/
   3559 	if (ahc->features & AHC_TWIN) {
   3560 
   3561 		/*
   3562 		 * The device is gated to channel B after a chip reset,
   3563 		 * so set those values first
   3564 		 */
   3565 		term = (ahc->flags & AHC_TERM_ENB_B) != 0 ? STPWEN : 0;
   3566 		if ((ahc->features & AHC_ULTRA2) != 0)
   3567 			ahc_outb(ahc, SCSIID_ULTRA2, ahc->our_id_b);
   3568 		else
   3569 			ahc_outb(ahc, SCSIID, ahc->our_id_b);
   3570 		scsi_conf = ahc_inb(ahc, SCSICONF + 1);
   3571 		ahc_outb(ahc, SXFRCTL1, (scsi_conf & (ENSPCHK|STIMESEL))
   3572 					|term|ENSTIMER|ACTNEGEN);
   3573 		ahc_outb(ahc, SIMODE1, ENSELTIMO|ENSCSIRST|ENSCSIPERR);
   3574 		ahc_outb(ahc, SXFRCTL0, DFON|SPIOEN);
   3575 
   3576 		if ((scsi_conf & RESET_SCSI) != 0
   3577 		 && (ahc->flags & AHC_INITIATORMODE) != 0)
   3578 			ahc->flags |= AHC_RESET_BUS_B;
   3579 
   3580 		/* Select Channel A */
   3581 		ahc_outb(ahc, SBLKCTL, ahc_inb(ahc, SBLKCTL) & ~SELBUSB);
   3582 	}
   3583 	term = (ahc->flags & AHC_TERM_ENB_A) != 0 ? STPWEN : 0;
   3584 	if ((ahc->features & AHC_ULTRA2) != 0)
   3585 		ahc_outb(ahc, SCSIID_ULTRA2, ahc->our_id);
   3586 	else
   3587 		ahc_outb(ahc, SCSIID, ahc->our_id);
   3588 	scsi_conf = ahc_inb(ahc, SCSICONF);
   3589 	ahc_outb(ahc, SXFRCTL1, (scsi_conf & (ENSPCHK|STIMESEL))
   3590 				|term
   3591 				|ENSTIMER|ACTNEGEN);
   3592 	ahc_outb(ahc, SIMODE1, ENSELTIMO|ENSCSIRST|ENSCSIPERR);
   3593 	ahc_outb(ahc, SXFRCTL0, DFON|SPIOEN);
   3594 
   3595 	if ((scsi_conf & RESET_SCSI) != 0
   3596 	 && (ahc->flags & AHC_INITIATORMODE) != 0)
   3597 		ahc->flags |= AHC_RESET_BUS_A;
   3598 
   3599 	/*
   3600 	 * Look at the information that board initialization or
   3601 	 * the board bios has left us.
   3602 	 */
   3603 	ultraenb = 0;
   3604 	tagenable = ALL_TARGETS_MASK;
   3605 
   3606 	/* Grab the disconnection disable table and invert it for our needs */
   3607 	if (ahc->flags & AHC_USEDEFAULTS) {
   3608 		printf("%s: Host Adapter Bios disabled.  Using default SCSI "
   3609 			"device parameters\n", ahc_name(ahc));
   3610 		ahc->flags |= AHC_EXTENDED_TRANS_A|AHC_EXTENDED_TRANS_B|
   3611 			      AHC_TERM_ENB_A|AHC_TERM_ENB_B;
   3612 		discenable = ALL_TARGETS_MASK;
   3613 		if ((ahc->features & AHC_ULTRA) != 0)
   3614 			ultraenb = ALL_TARGETS_MASK;
   3615 	} else {
   3616 		discenable = ~((ahc_inb(ahc, DISC_DSB + 1) << 8)
   3617 			   | ahc_inb(ahc, DISC_DSB));
   3618 		if ((ahc->features & (AHC_ULTRA|AHC_ULTRA2)) != 0)
   3619 			ultraenb = (ahc_inb(ahc, ULTRA_ENB + 1) << 8)
   3620 				      | ahc_inb(ahc, ULTRA_ENB);
   3621 	}
   3622 
   3623 	if ((ahc->features & (AHC_WIDE|AHC_TWIN)) == 0)
   3624 		max_targ = 7;
   3625 
   3626 	for (i = 0; i <= max_targ; i++) {
   3627 		struct ahc_initiator_tinfo *tinfo;
   3628 		struct tmode_tstate *tstate;
   3629 		u_int our_id;
   3630 		u_int target_id;
   3631 		char channel;
   3632 
   3633 		channel = 'A';
   3634 		our_id = ahc->our_id;
   3635 		target_id = i;
   3636 		if (i > 7 && (ahc->features & AHC_TWIN) != 0) {
   3637 			channel = 'B';
   3638 			our_id = ahc->our_id_b;
   3639 			target_id = i % 8;
   3640 		}
   3641 		tinfo = ahc_fetch_transinfo(ahc, channel, our_id,
   3642 					    target_id, &tstate);
   3643 		/* Default to async narrow across the board */
   3644 		memset(tinfo, 0, sizeof(*tinfo));
   3645 		if (ahc->flags & AHC_USEDEFAULTS) {
   3646 			if ((ahc->features & AHC_WIDE) != 0)
   3647 				tinfo->user.width = MSG_EXT_WDTR_BUS_16_BIT;
   3648 
   3649 			/*
   3650 			 * These will be truncated when we determine the
   3651 			 * connection type we have with the target.
   3652 			 */
   3653 			tinfo->user.period = ahc_syncrates->period;
   3654 			tinfo->user.offset = ~0;
   3655 		} else {
   3656 			u_int scsirate;
   3657 			u_int16_t mask;
   3658 
   3659 			/* Take the settings leftover in scratch RAM. */
   3660 			scsirate = ahc_inb(ahc, TARG_SCSIRATE + i);
   3661 			mask = (0x01 << i);
   3662 			if ((ahc->features & AHC_ULTRA2) != 0) {
   3663 				u_int offset;
   3664 				u_int maxsync;
   3665 
   3666 				if ((scsirate & SOFS) == 0x0F) {
   3667 					/*
   3668 					 * Haven't negotiated yet,
   3669 					 * so the format is different.
   3670 					 */
   3671 					scsirate = (scsirate & SXFR) >> 4
   3672 						 | (ultraenb & mask)
   3673 						  ? 0x08 : 0x0
   3674 						 | (scsirate & WIDEXFER);
   3675 					offset = MAX_OFFSET_ULTRA2;
   3676 				} else
   3677 					offset = ahc_inb(ahc, TARG_OFFSET + i);
   3678 				maxsync = AHC_SYNCRATE_ULTRA2;
   3679 				if ((ahc->features & AHC_DT) != 0)
   3680 					maxsync = AHC_SYNCRATE_DT;
   3681 				tinfo->user.period =
   3682 				    ahc_find_period(ahc, scsirate, maxsync);
   3683 				if (offset == 0)
   3684 					tinfo->user.period = 0;
   3685 				else
   3686 					tinfo->user.offset = ~0;
   3687 			} else if ((scsirate & SOFS) != 0) {
   3688 				tinfo->user.period =
   3689 				    ahc_find_period(ahc, scsirate,
   3690 						    (ultraenb & mask)
   3691 						   ? AHC_SYNCRATE_ULTRA
   3692 						   : AHC_SYNCRATE_FAST);
   3693 				if (tinfo->user.period != 0)
   3694 					tinfo->user.offset = ~0;
   3695 			}
   3696 			if ((scsirate & WIDEXFER) != 0
   3697 			 && (ahc->features & AHC_WIDE) != 0)
   3698 				tinfo->user.width = MSG_EXT_WDTR_BUS_16_BIT;
   3699 		}
   3700 		tinfo->goal = tinfo->user; /* force negotiation */
   3701 		tstate->ultraenb = ultraenb;
   3702 		tstate->discenable = discenable;
   3703 		tstate->tagenable = 0; /* Wait until the XPT says its okay */
   3704 		tstate->tagdisable = 0;
   3705 	}
   3706 	ahc->user_discenable = discenable;
   3707 	ahc->user_tagenable = tagenable;
   3708 
   3709 	/*
   3710 	 * Tell the sequencer where it can find our arrays in memory.
   3711 	 */
   3712 	physaddr = ahc->scb_data->hscb_busaddr;
   3713 	ahc_outb(ahc, HSCB_ADDR, physaddr & 0xFF);
   3714 	ahc_outb(ahc, HSCB_ADDR + 1, (physaddr >> 8) & 0xFF);
   3715 	ahc_outb(ahc, HSCB_ADDR + 2, (physaddr >> 16) & 0xFF);
   3716 	ahc_outb(ahc, HSCB_ADDR + 3, (physaddr >> 24) & 0xFF);
   3717 
   3718 	physaddr = ahc->shared_data_busaddr;
   3719 	ahc_outb(ahc, SCBID_ADDR, physaddr & 0xFF);
   3720 	ahc_outb(ahc, SCBID_ADDR + 1, (physaddr >> 8) & 0xFF);
   3721 	ahc_outb(ahc, SCBID_ADDR + 2, (physaddr >> 16) & 0xFF);
   3722 	ahc_outb(ahc, SCBID_ADDR + 3, (physaddr >> 24) & 0xFF);
   3723 
   3724 	/* Target mode incomding command fifo */
   3725 	physaddr += 3 * 256 * sizeof(u_int8_t);
   3726 	ahc_outb(ahc, TMODE_CMDADDR, physaddr & 0xFF);
   3727 	ahc_outb(ahc, TMODE_CMDADDR + 1, (physaddr >> 8) & 0xFF);
   3728 	ahc_outb(ahc, TMODE_CMDADDR + 2, (physaddr >> 16) & 0xFF);
   3729 	ahc_outb(ahc, TMODE_CMDADDR + 3, (physaddr >> 24) & 0xFF);
   3730 
   3731 	/*
   3732 	 * Initialize the group code to command length table.
   3733 	 * This overrides the values in TARG_SCSIRATE, so only
   3734 	 * setup the table after we have processed that information.
   3735 	 */
   3736 	ahc_outb(ahc, CMDSIZE_TABLE, 5);
   3737 	ahc_outb(ahc, CMDSIZE_TABLE + 1, 9);
   3738 	ahc_outb(ahc, CMDSIZE_TABLE + 2, 9);
   3739 	ahc_outb(ahc, CMDSIZE_TABLE + 3, 0);
   3740 	ahc_outb(ahc, CMDSIZE_TABLE + 4, 15);
   3741 	ahc_outb(ahc, CMDSIZE_TABLE + 5, 11);
   3742 	ahc_outb(ahc, CMDSIZE_TABLE + 6, 0);
   3743 	ahc_outb(ahc, CMDSIZE_TABLE + 7, 0);
   3744 
   3745 	/* Tell the sequencer of our initial queue positions */
   3746 	ahc_outb(ahc, KERNEL_QINPOS, 0);
   3747 	ahc_outb(ahc, QINPOS, 0);
   3748 	ahc_outb(ahc, QOUTPOS, 0);
   3749 
   3750 #ifdef AHC_DEBUG
   3751 	if (ahc_debug & AHC_SHOWMISC)
   3752 		printf("DISCENABLE == 0x%x\nULTRAENB == 0x%x\n",
   3753 		       discenable, ultraenb);
   3754 #endif
   3755 
   3756 	/* Don't have any special messages to send to targets */
   3757 	ahc_outb(ahc, TARGET_MSG_REQUEST, 0);
   3758 	ahc_outb(ahc, TARGET_MSG_REQUEST + 1, 0);
   3759 
   3760 	/*
   3761 	 * Use the built in queue management registers
   3762 	 * if they are available.
   3763 	 */
   3764 	if ((ahc->features & AHC_QUEUE_REGS) != 0) {
   3765 		ahc_outb(ahc, QOFF_CTLSTA, SCB_QSIZE_256);
   3766 		ahc_outb(ahc, SDSCB_QOFF, 0);
   3767 		ahc_outb(ahc, SNSCB_QOFF, 0);
   3768 		ahc_outb(ahc, HNSCB_QOFF, 0);
   3769 	}
   3770 
   3771 
   3772 	/* We don't have any waiting selections */
   3773 	ahc_outb(ahc, WAITING_SCBH, SCB_LIST_NULL);
   3774 
   3775 	/* Our disconnection list is empty too */
   3776 	ahc_outb(ahc, DISCONNECTED_SCBH, SCB_LIST_NULL);
   3777 
   3778 	/* Message out buffer starts empty */
   3779 	ahc_outb(ahc, MSG_OUT, MSG_NOOP);
   3780 
   3781 	/*
   3782 	 * Setup the allowed SCSI Sequences based on operational mode.
   3783 	 * If we are a target, we'll enable select in operations once
   3784 	 * we've had a lun enabled.
   3785 	 */
   3786 	scsiseq_template = ENSELO|ENAUTOATNO|ENAUTOATNP;
   3787 	if ((ahc->flags & AHC_INITIATORMODE) != 0)
   3788 		scsiseq_template |= ENRSELI;
   3789 	ahc_outb(ahc, SCSISEQ_TEMPLATE, scsiseq_template);
   3790 
   3791 	/*
   3792 	 * Load the Sequencer program and Enable the adapter
   3793 	 * in "fast" mode.
   3794          */
   3795 #ifdef AHC_DEBUG
   3796 	printf("%s: Downloading Sequencer Program...",
   3797 	       ahc_name(ahc));
   3798 #endif
   3799 
   3800 	ahc_loadseq(ahc);
   3801 
   3802 	/* We have to wait until after any system dumps... */
   3803 	shutdownhook_establish(ahc_shutdown, ahc);
   3804 
   3805 	return (0);
   3806 }
   3807 
   3808 static int
   3809 ahc_ioctl(struct scsipi_channel *channel, u_long cmd, caddr_t addr, int flag,
   3810 	  struct proc *p)
   3811 {
   3812 	struct ahc_softc *ahc = (void *)channel->chan_adapter->adapt_dev;
   3813 	int s, ret = ENOTTY;
   3814 
   3815 	switch (cmd) {
   3816 	case SCBUSIORESET:
   3817 		s = splbio();
   3818 		ahc_reset_channel(ahc, channel->chan_channel == 1 ? 'B' : 'A',
   3819 		    TRUE);
   3820 		splx(s);
   3821 		ret = 0;
   3822 		break;
   3823 	default:
   3824 		break;
   3825 	}
   3826 
   3827 	return ret;
   3828 }
   3829 
   3830 
   3831 /*
   3832  * XXX fvdl the busy_tcl checks and settings should only be done
   3833  * for the non-tagged queueing case, but we don't do tagged queueing
   3834  * yet, so..
   3835  */
   3836 static void
   3837 ahc_action(struct scsipi_channel *chan, scsipi_adapter_req_t req, void *arg)
   3838 {
   3839 	struct scsipi_xfer *xs;
   3840 	struct scsipi_periph *periph;
   3841 	struct ahc_softc *ahc = (void *)chan->chan_adapter->adapt_dev;
   3842 	struct scb *scb;
   3843 	struct hardware_scb *hscb;
   3844 	struct ahc_initiator_tinfo *tinfo;
   3845 	struct tmode_tstate *tstate;
   3846 	u_int target_id;
   3847 	u_int our_id;
   3848 	int s, tcl;
   3849 	u_int16_t mask;
   3850 	char channel;
   3851 
   3852 	switch (req) {
   3853 	case ADAPTER_REQ_RUN_XFER:
   3854 		xs = arg;
   3855 		periph = xs->xs_periph;
   3856 
   3857 		SC_DEBUG(xs->xs_periph, SCSIPI_DB3, ("ahc_action\n"));
   3858 
   3859 		/* must protect the queue */
   3860 		s = splbio();
   3861 
   3862 		tcl = XS_TCL(ahc, xs);
   3863 
   3864 		if (!ahc_istagged_device(ahc, xs, 0) &&
   3865 		     ahc_index_busy_tcl(ahc, tcl, FALSE) != SCB_LIST_NULL) {
   3866 			panic("ahc_action: not tagged and device busy");
   3867 		}
   3868 
   3869 
   3870 		target_id = periph->periph_target;
   3871 		our_id = SIM_SCSI_ID(ahc, periph);
   3872 
   3873 		/*
   3874 		 * get an scb to use.
   3875 		 */
   3876 		if ((scb = ahcgetscb(ahc)) == NULL) {
   3877 			xs->error = XS_RESOURCE_SHORTAGE;
   3878 			scsipi_done(xs);
   3879 			splx(s);
   3880 			return;
   3881 		}
   3882 
   3883 		tcl = XS_TCL(ahc, xs);
   3884 
   3885 #ifdef DIAGNOSTIC
   3886 		if (!ahc_istagged_device(ahc, xs, 0) &&
   3887 		    ahc_index_busy_tcl(ahc, tcl, FALSE) != SCB_LIST_NULL)
   3888 			panic("ahc: queuing for busy target");
   3889 #endif
   3890 
   3891 		scb->xs = xs;
   3892 		hscb = scb->hscb;
   3893 		hscb->tcl = tcl;
   3894 
   3895 		if (xs->xs_tag_type) {
   3896 #ifdef DIAGNOSTIC
   3897 		if (ahc_istagged_device(ahc, xs, 0) == 0)
   3898 			panic("ahc_action: taggged command for untagged device");
   3899 #endif
   3900 			scb->hscb->control |= TAG_ENB;
   3901 		} else
   3902 			ahc_busy_tcl(ahc, scb);
   3903 
   3904 		splx(s);
   3905 
   3906 		channel = SIM_CHANNEL(ahc, periph);
   3907 		if (ahc->inited_channels[channel - 'A'] == 0) {
   3908 			if ((channel == 'A' &&
   3909 			     (ahc->flags & AHC_RESET_BUS_A)) ||
   3910 			    (channel == 'B' &&
   3911 			     (ahc->flags & AHC_RESET_BUS_B))) {
   3912 				s = splbio();
   3913 				ahc_reset_channel(ahc, channel, TRUE);
   3914 				splx(s);
   3915 			}
   3916 			ahc->inited_channels[channel - 'A'] = 1;
   3917 		}
   3918 
   3919 		/*
   3920 		 * Put all the arguments for the xfer in the scb
   3921 		 */
   3922 
   3923 		mask = SCB_TARGET_MASK(scb);
   3924 		tinfo = ahc_fetch_transinfo(ahc,
   3925 			    SIM_CHANNEL(ahc, periph),
   3926 			    our_id, target_id, &tstate);
   3927 		if (ahc->inited_targets[target_id] == 0) {
   3928 			struct ahc_devinfo devinfo;
   3929 			s = splbio();
   3930 			ahc_compile_devinfo(&devinfo, our_id, target_id,
   3931 			    periph->periph_lun,
   3932 			    SIM_CHANNEL(ahc, periph),
   3933 			    ROLE_INITIATOR);
   3934 			ahc_update_target_msg_request(ahc, &devinfo, tinfo,
   3935 			    TRUE, FALSE);
   3936 			ahc->inited_targets[target_id] = 1;
   3937 			splx(s);
   3938 		}
   3939 		hscb->scsirate = tinfo->scsirate;
   3940 		hscb->scsioffset = tinfo->current.offset;
   3941 		if ((tstate->ultraenb & mask) != 0)
   3942 			hscb->control |= ULTRAENB;
   3943 
   3944 		if ((tstate->discenable & mask) != 0)
   3945 			hscb->control |= DISCENB;
   3946 
   3947 		if (xs->xs_control & XS_CTL_RESET) {
   3948 			hscb->cmdpointer = 0;
   3949 			scb->flags |= SCB_DEVICE_RESET;
   3950 			hscb->control |= MK_MESSAGE;
   3951 			ahc_execute_scb(scb, NULL, 0);
   3952 		}
   3953 
   3954 		ahc_setup_data(ahc, xs, scb);
   3955 		return;
   3956 	case ADAPTER_REQ_GROW_RESOURCES:
   3957 		/* XXX not supported */
   3958 		return;
   3959 	case ADAPTER_REQ_SET_XFER_MODE:
   3960 	{
   3961 		struct scsipi_xfer_mode *xm = arg;
   3962 		struct ahc_devinfo devinfo;
   3963 		int target_id, our_id;
   3964 		char channel;
   3965 
   3966 		target_id = xm->xm_target;
   3967 		our_id = chan->chan_id;
   3968 		channel = (chan->chan_channel == 1) ? 'B' : 'A';
   3969 		s = splbio();
   3970 		tinfo = ahc_fetch_transinfo(ahc, channel, our_id, target_id,
   3971 		    &tstate);
   3972 		ahc_compile_devinfo(&devinfo, our_id, target_id,
   3973 		    0, channel, ROLE_INITIATOR);
   3974 		ahc->inited_targets[target_id] = 2;
   3975 		if (xm->xm_mode & PERIPH_CAP_TQING &&
   3976 		    (tstate->tagdisable & devinfo.target_mask) == 0) {
   3977 			ahc_set_tags(ahc, &devinfo, TRUE);
   3978 		}
   3979 		splx(s);
   3980 		ahc_update_xfer_mode(ahc, &devinfo);
   3981 	}
   3982 	}
   3983 }
   3984 
   3985 static void
   3986 ahc_execute_scb(void *arg, bus_dma_segment_t *dm_segs, int nsegments)
   3987 {
   3988 	struct	 scb *scb;
   3989 	struct scsipi_xfer *xs;
   3990 	struct	 ahc_softc *ahc;
   3991 	int	 s;
   3992 
   3993 	scb = (struct scb *)arg;
   3994 	xs = scb->xs;
   3995 	ahc = (void *)xs->xs_periph->periph_channel->chan_adapter->adapt_dev;
   3996 
   3997 
   3998 	if (nsegments != 0) {
   3999 		struct	  ahc_dma_seg *sg;
   4000 		bus_dma_segment_t *end_seg;
   4001 		int op;
   4002 
   4003 		end_seg = dm_segs + nsegments;
   4004 
   4005 		/* Copy the first SG into the data pointer area */
   4006 		scb->hscb->data = dm_segs->ds_addr;
   4007 		scb->hscb->datalen = dm_segs->ds_len;
   4008 
   4009 		/* Copy the segments into our SG list */
   4010 		sg = scb->sg_list;
   4011 		while (dm_segs < end_seg) {
   4012 			sg->addr = dm_segs->ds_addr;
   4013 			sg->len = dm_segs->ds_len;
   4014 			ahc_swap_sg(sg);
   4015 			sg++;
   4016 			dm_segs++;
   4017 		}
   4018 
   4019 		/* Note where to find the SG entries in bus space */
   4020 		scb->hscb->SG_pointer = scb->sg_list_phys;
   4021 
   4022 		if (xs->xs_control & XS_CTL_DATA_IN)
   4023 			op = BUS_DMASYNC_PREREAD;
   4024 		else
   4025 			op = BUS_DMASYNC_PREWRITE;
   4026 
   4027 		bus_dmamap_sync(ahc->parent_dmat, scb->dmamap, 0,
   4028 		    scb->dmamap->dm_mapsize, op);
   4029 
   4030 	} else {
   4031 		scb->hscb->SG_pointer = 0;
   4032 		scb->hscb->data = 0;
   4033 		scb->hscb->datalen = 0;
   4034 	}
   4035 
   4036 	scb->sg_count = scb->hscb->SG_count = nsegments;
   4037 
   4038 	s = splbio();
   4039 
   4040 	/*
   4041 	 * Last time we need to check if this SCB needs to
   4042 	 * be aborted.
   4043 	 */
   4044 	if (xs->xs_status & XS_STS_DONE) {
   4045 		if (!ahc_istagged_device(ahc, xs, 0))
   4046 			ahc_index_busy_tcl(ahc, scb->hscb->tcl, TRUE);
   4047 		if (nsegments != 0)
   4048 			bus_dmamap_unload(ahc->parent_dmat, scb->dmamap);
   4049 		ahcfreescb(ahc, scb);
   4050 		splx(s);
   4051 		return;
   4052 	}
   4053 
   4054 #ifdef DIAGNOSTIC
   4055 	if (scb->sg_count > 255)
   4056 		panic("ahc bad sg_count");
   4057 #endif
   4058 
   4059 	ahc_swap_hscb(scb->hscb);
   4060 
   4061 	LIST_INSERT_HEAD(&ahc->pending_ccbs, scb, plinks);
   4062 
   4063 	scb->flags |= SCB_ACTIVE;
   4064 
   4065 	if (!(xs->xs_control & XS_CTL_POLL))
   4066 		callout_reset(&scb->xs->xs_callout, (xs->timeout * hz) / 1000,
   4067 		    ahc_timeout, scb);
   4068 
   4069 	if ((scb->flags & SCB_TARGET_IMMEDIATE) != 0) {
   4070 #if 0
   4071 		printf("Continueing Immediate Command %d:%d\n",
   4072 		       xs->xs_periph->periph_target,
   4073 		       xs->xs_periph->periph_lun);
   4074 #endif
   4075 		pause_sequencer(ahc);
   4076 		if ((ahc->flags & AHC_PAGESCBS) == 0)
   4077 			ahc_outb(ahc, SCBPTR, scb->hscb->tag);
   4078 		ahc_outb(ahc, SCB_TAG, scb->hscb->tag);
   4079 		ahc_outb(ahc, RETURN_1, CONT_MSG_LOOP);
   4080 		unpause_sequencer(ahc);
   4081 	} else {
   4082 
   4083 #if 0
   4084 		printf("tag %x at qpos %u vaddr %p paddr 0x%lx\n",
   4085 		    scb->hscb->tag, ahc->qinfifonext,
   4086 		    &ahc->qinfifo[ahc->qinfifonext],
   4087 		    ahc->shared_data_busaddr + 1024 + ahc->qinfifonext);
   4088 #endif
   4089 
   4090 		ahc->qinfifo[ahc->qinfifonext++] = scb->hscb->tag;
   4091 
   4092 		bus_dmamap_sync(ahc->parent_dmat, ahc->shared_data_dmamap,
   4093 		    QINFIFO_OFFSET * 256, 256, BUS_DMASYNC_PREWRITE);
   4094 
   4095 		if ((ahc->features & AHC_QUEUE_REGS) != 0) {
   4096 			ahc_outb(ahc, HNSCB_QOFF, ahc->qinfifonext);
   4097 		} else {
   4098 			pause_sequencer(ahc);
   4099 			ahc_outb(ahc, KERNEL_QINPOS, ahc->qinfifonext);
   4100 			unpause_sequencer(ahc);
   4101 		}
   4102 	}
   4103 
   4104 #ifdef AHC_DEBUG
   4105 	if (ahc_debug & AHC_SHOWCMDS) {
   4106 		scsi_print_addr(xs->xs_periph);
   4107 		printf("opcode %d tag %x len %d flags %x control %x fpos %u"
   4108 		    " rate %x\n",
   4109 		    xs->cmdstore.opcode, scb->hscb->tag, scb->hscb->datalen,
   4110 		    scb->flags, scb->hscb->control, ahc->qinfifonext,
   4111 		    scb->hscb->scsirate);
   4112 	}
   4113 #endif
   4114 
   4115 	if (!(xs->xs_control & XS_CTL_POLL)) {
   4116 		splx(s);
   4117 		return;
   4118 	}
   4119 	/*
   4120 	 * If we can't use interrupts, poll for completion
   4121 	 */
   4122 	SC_DEBUG(xs->xs_periph, SCSIPI_DB3, ("cmd_poll\n"));
   4123 	do {
   4124 		if (ahc_poll(ahc, xs->timeout)) {
   4125 			if (!(xs->xs_control & XS_CTL_SILENT))
   4126 				printf("cmd fail\n");
   4127 			ahc_timeout(scb);
   4128 			break;
   4129 		}
   4130 	} while (!(xs->xs_status & XS_STS_DONE));
   4131 	splx(s);
   4132 	return;
   4133 }
   4134 
   4135 static int
   4136 ahc_poll(struct ahc_softc *ahc, int wait)
   4137 {
   4138 	while (--wait) {
   4139 		DELAY(1000);
   4140 		if (ahc_inb(ahc, INTSTAT) & INT_PEND)
   4141 			break;
   4142 	}
   4143 
   4144 	if (wait == 0) {
   4145 		printf("%s: board is not responding\n", ahc_name(ahc));
   4146 		return (EIO);
   4147 	}
   4148 
   4149 	ahc_intr((void *)ahc);
   4150 	return (0);
   4151 }
   4152 
   4153 static void
   4154 ahc_setup_data(struct ahc_softc *ahc, struct scsipi_xfer *xs,
   4155 	       struct scb *scb)
   4156 {
   4157 	struct hardware_scb *hscb;
   4158 
   4159 	hscb = scb->hscb;
   4160 	xs->resid = xs->status = 0;
   4161 
   4162 	hscb->cmdlen = xs->cmdlen;
   4163 	memcpy(hscb->cmdstore, xs->cmd, xs->cmdlen);
   4164 	hscb->cmdpointer = hscb->cmdstore_busaddr;
   4165 
   4166 	/* Only use S/G if there is a transfer */
   4167 	if (xs->datalen) {
   4168 		int error;
   4169 
   4170 		error = bus_dmamap_load(ahc->parent_dmat,
   4171 			    scb->dmamap, xs->data,
   4172 			    xs->datalen, NULL,
   4173 			    ((xs->xs_control & XS_CTL_NOSLEEP) ?
   4174 			     BUS_DMA_NOWAIT : BUS_DMA_WAITOK) |
   4175 			    BUS_DMA_STREAMING);
   4176 		if (error) {
   4177 			if (!ahc_istagged_device(ahc, xs, 0))
   4178 				ahc_index_busy_tcl(ahc, hscb->tcl, TRUE);
   4179 			xs->error = XS_RESOURCE_SHORTAGE;	/* XXX fvdl */
   4180 			scsipi_done(xs);
   4181 			return;
   4182 		}
   4183 		ahc_execute_scb(scb,
   4184 		    scb->dmamap->dm_segs,
   4185 		    scb->dmamap->dm_nsegs);
   4186 	} else {
   4187 		ahc_execute_scb(scb, NULL, 0);
   4188 	}
   4189 }
   4190 
   4191 static void
   4192 ahc_freeze_devq(struct ahc_softc *ahc, struct scsipi_periph *periph)
   4193 {
   4194 	int	target;
   4195 	char	channel;
   4196 	int	lun;
   4197 
   4198 	target = periph->periph_target;
   4199 	lun = periph->periph_lun;
   4200 	channel = periph->periph_channel->chan_channel;
   4201 
   4202 	ahc_search_qinfifo(ahc, target, channel, lun,
   4203 			   /*tag*/SCB_LIST_NULL, ROLE_UNKNOWN,
   4204 			   SCB_REQUEUE, SEARCH_COMPLETE);
   4205 }
   4206 
   4207 static void
   4208 ahcallocscbs(struct ahc_softc *ahc)
   4209 {
   4210 	struct scb_data *scb_data;
   4211 	struct scb *next_scb;
   4212 	struct sg_map_node *sg_map;
   4213 	bus_addr_t physaddr;
   4214 	struct ahc_dma_seg *segs;
   4215 	int newcount;
   4216 	int i;
   4217 
   4218 	scb_data = ahc->scb_data;
   4219 	if (scb_data->numscbs >= AHC_SCB_MAX)
   4220 		/* Can't allocate any more */
   4221 		return;
   4222 
   4223 	next_scb = &scb_data->scbarray[scb_data->numscbs];
   4224 
   4225 	sg_map = malloc(sizeof(*sg_map), M_DEVBUF, M_NOWAIT);
   4226 
   4227 	if (sg_map == NULL)
   4228 		return;
   4229 
   4230 	if (ahc_createdmamem(ahc->parent_dmat, PAGE_SIZE, ahc->sc_dmaflags,
   4231 	    &sg_map->sg_dmamap,
   4232 	    (caddr_t *)&sg_map->sg_vaddr, &sg_map->sg_physaddr,
   4233 	    &sg_map->sg_dmasegs, &sg_map->sg_nseg, ahc_name(ahc),
   4234 	    "SG space") < 0) {
   4235 		free(sg_map, M_DEVBUF);
   4236 		return;
   4237 	}
   4238 
   4239 	SLIST_INSERT_HEAD(&scb_data->sg_maps, sg_map, links);
   4240 
   4241 	segs = sg_map->sg_vaddr;
   4242 	physaddr = sg_map->sg_physaddr;
   4243 
   4244 	newcount = (PAGE_SIZE / (AHC_NSEG * sizeof(struct ahc_dma_seg)));
   4245 	for (i = 0; scb_data->numscbs < AHC_SCB_MAX && i < newcount; i++) {
   4246 		int error;
   4247 
   4248 		next_scb->sg_list = segs;
   4249 		/*
   4250 		 * The sequencer always starts with the second entry.
   4251 		 * The first entry is embedded in the scb.
   4252 		 */
   4253 		next_scb->sg_list_phys = physaddr + sizeof(struct ahc_dma_seg);
   4254 		next_scb->flags = SCB_FREE;
   4255 		error = bus_dmamap_create(ahc->parent_dmat,
   4256 			    AHC_MAXTRANSFER_SIZE, AHC_NSEG, MAXBSIZE, 0,
   4257 			    BUS_DMA_NOWAIT|BUS_DMA_ALLOCNOW|ahc->sc_dmaflags,
   4258 			    &next_scb->dmamap);
   4259 		if (error != 0)
   4260 			break;
   4261 		next_scb->hscb = &scb_data->hscbs[scb_data->numscbs];
   4262 		next_scb->hscb->tag = ahc->scb_data->numscbs;
   4263 		next_scb->hscb->cmdstore_busaddr =
   4264 		    ahc_hscb_busaddr(ahc, next_scb->hscb->tag)
   4265 		  + offsetof(struct hardware_scb, cmdstore);
   4266 		next_scb->hscb->cmdstore_busaddr =
   4267 		    htole32(next_scb->hscb->cmdstore_busaddr);
   4268 		SLIST_INSERT_HEAD(&ahc->scb_data->free_scbs, next_scb, links);
   4269 		segs += AHC_NSEG;
   4270 		physaddr += (AHC_NSEG * sizeof(struct ahc_dma_seg));
   4271 		next_scb++;
   4272 		ahc->scb_data->numscbs++;
   4273 	}
   4274 #ifdef AHC_DEBUG
   4275 	if (ahc_debug & AHC_SHOWSCBALLOC)
   4276 		printf("%s: allocated %d new SCBs count now %d\n",
   4277 		    ahc_name(ahc), i - 1, ahc->scb_data->numscbs);
   4278 #endif
   4279 }
   4280 
   4281 #ifdef AHC_DUMP_SEQ
   4282 static void
   4283 ahc_dumpseq(struct ahc_softc* ahc)
   4284 {
   4285 	int i;
   4286 	int max_prog;
   4287 
   4288 	if ((ahc->chip & AHC_BUS_MASK) < AHC_PCI)
   4289 		max_prog = 448;
   4290 	else if ((ahc->features & AHC_ULTRA2) != 0)
   4291 		max_prog = 768;
   4292 	else
   4293 		max_prog = 512;
   4294 
   4295 	ahc_outb(ahc, SEQCTL, PERRORDIS|FAILDIS|FASTMODE|LOADRAM);
   4296 	ahc_outb(ahc, SEQADDR0, 0);
   4297 	ahc_outb(ahc, SEQADDR1, 0);
   4298 	for (i = 0; i < max_prog; i++) {
   4299 		u_int8_t ins_bytes[4];
   4300 
   4301 		ahc_insb(ahc, SEQRAM, ins_bytes, 4);
   4302 		printf("0x%08x\n", ins_bytes[0] << 24
   4303 				 | ins_bytes[1] << 16
   4304 				 | ins_bytes[2] << 8
   4305 				 | ins_bytes[3]);
   4306 	}
   4307 }
   4308 #endif
   4309 
   4310 static void
   4311 ahc_loadseq(struct ahc_softc *ahc)
   4312 {
   4313 	const struct patch *cur_patch;
   4314 	int i;
   4315 	int downloaded;
   4316 	int skip_addr;
   4317 	u_int8_t download_consts[4];
   4318 
   4319 	/* Setup downloadable constant table */
   4320 #if 0
   4321 	/* No downloaded constants are currently defined. */
   4322 	download_consts[TMODE_NUMCMDS] = ahc->num_targetcmds;
   4323 #endif
   4324 
   4325 	cur_patch = patches;
   4326 	downloaded = 0;
   4327 	skip_addr = 0;
   4328 	ahc_outb(ahc, SEQCTL, PERRORDIS|FAILDIS|FASTMODE|LOADRAM);
   4329 	ahc_outb(ahc, SEQADDR0, 0);
   4330 	ahc_outb(ahc, SEQADDR1, 0);
   4331 
   4332 	for (i = 0; i < sizeof(seqprog)/4; i++) {
   4333 		if (ahc_check_patch(ahc, &cur_patch, i, &skip_addr) == 0) {
   4334 			/*
   4335 			 * Don't download this instruction as it
   4336 			 * is in a patch that was removed.
   4337 			 */
   4338                         continue;
   4339 		}
   4340 		ahc_download_instr(ahc, i, download_consts);
   4341 		downloaded++;
   4342 	}
   4343 	ahc_outb(ahc, SEQCTL, PERRORDIS|FAILDIS|FASTMODE);
   4344 	restart_sequencer(ahc);
   4345 
   4346 #ifdef AHC_DEBUG
   4347 	printf(" %d instructions downloaded\n", downloaded);
   4348 #endif
   4349 }
   4350 
   4351 static int
   4352 ahc_check_patch(struct ahc_softc *ahc, const struct patch **start_patch,
   4353 		int start_instr, int *skip_addr)
   4354 {
   4355 	const struct	patch *cur_patch;
   4356 	const struct	patch *last_patch;
   4357 	int	num_patches;
   4358 
   4359 	num_patches = sizeof(patches)/sizeof(struct patch);
   4360 	last_patch = &patches[num_patches];
   4361 	cur_patch = *start_patch;
   4362 
   4363 	while (cur_patch < last_patch && start_instr == cur_patch->begin) {
   4364 
   4365 		if (cur_patch->patch_func(ahc) == 0) {
   4366 
   4367 			/* Start rejecting code */
   4368 			*skip_addr = start_instr + cur_patch->skip_instr;
   4369 			cur_patch += cur_patch->skip_patch;
   4370 		} else {
   4371 			/* Accepted this patch.  Advance to the next
   4372 			 * one and wait for our intruction pointer to
   4373 			 * hit this point.
   4374 			 */
   4375 			cur_patch++;
   4376 		}
   4377 	}
   4378 
   4379 	*start_patch = cur_patch;
   4380 	if (start_instr < *skip_addr)
   4381 		/* Still skipping */
   4382 		return (0);
   4383 
   4384 	return (1);
   4385 }
   4386 
   4387 static void
   4388 ahc_download_instr(struct ahc_softc *ahc, int instrptr, u_int8_t *dconsts)
   4389 {
   4390 	union	ins_formats instr;
   4391 	struct	ins_format1 *fmt1_ins;
   4392 	struct	ins_format3 *fmt3_ins;
   4393 	u_int	opcode;
   4394 
   4395 	/* Structure copy */
   4396 	memcpy(&instr, &seqprog[instrptr * 4], sizeof instr);
   4397 
   4398 	instr.integer = le32toh(instr.integer);
   4399 
   4400 	fmt1_ins = &instr.format1;
   4401 	fmt3_ins = NULL;
   4402 
   4403 	/* Pull the opcode */
   4404 	opcode = instr.format1.opcode;
   4405 	switch (opcode) {
   4406 	case AIC_OP_JMP:
   4407 	case AIC_OP_JC:
   4408 	case AIC_OP_JNC:
   4409 	case AIC_OP_CALL:
   4410 	case AIC_OP_JNE:
   4411 	case AIC_OP_JNZ:
   4412 	case AIC_OP_JE:
   4413 	case AIC_OP_JZ:
   4414 	{
   4415 		const struct patch *cur_patch;
   4416 		int address_offset;
   4417 		u_int address;
   4418 		int skip_addr;
   4419 		int i;
   4420 
   4421 		fmt3_ins = &instr.format3;
   4422 		address_offset = 0;
   4423 		address = fmt3_ins->address;
   4424 		cur_patch = patches;
   4425 		skip_addr = 0;
   4426 
   4427 		for (i = 0; i < address;) {
   4428 
   4429 			ahc_check_patch(ahc, &cur_patch, i, &skip_addr);
   4430 
   4431 			if (skip_addr > i) {
   4432 				int end_addr;
   4433 
   4434 				end_addr = MIN(address, skip_addr);
   4435 				address_offset += end_addr - i;
   4436 				i = skip_addr;
   4437 			} else {
   4438 				i++;
   4439 			}
   4440 		}
   4441 		address -= address_offset;
   4442 		fmt3_ins->address = address;
   4443 		/* FALLTHROUGH */
   4444 	}
   4445 	case AIC_OP_OR:
   4446 	case AIC_OP_AND:
   4447 	case AIC_OP_XOR:
   4448 	case AIC_OP_ADD:
   4449 	case AIC_OP_ADC:
   4450 	case AIC_OP_BMOV:
   4451 		if (fmt1_ins->parity != 0) {
   4452 			fmt1_ins->immediate = dconsts[fmt1_ins->immediate];
   4453 		}
   4454 		fmt1_ins->parity = 0;
   4455 		/* FALLTHROUGH */
   4456 	case AIC_OP_ROL:
   4457 		if ((ahc->features & AHC_ULTRA2) != 0) {
   4458 			int i, count;
   4459 
   4460 			/* Calculate odd parity for the instruction */
   4461 			for (i = 0, count = 0; i < 31; i++) {
   4462 				u_int32_t mask;
   4463 
   4464 				mask = 0x01 << i;
   4465 				if ((instr.integer & mask) != 0)
   4466 					count++;
   4467 			}
   4468 			if ((count & 0x01) == 0)
   4469 				instr.format1.parity = 1;
   4470 		} else {
   4471 			/* Compress the instruction for older sequencers */
   4472 			if (fmt3_ins != NULL) {
   4473 				instr.integer =
   4474 					fmt3_ins->immediate
   4475 				      | (fmt3_ins->source << 8)
   4476 				      | (fmt3_ins->address << 16)
   4477 				      |	(fmt3_ins->opcode << 25);
   4478 			} else {
   4479 				instr.integer =
   4480 					fmt1_ins->immediate
   4481 				      | (fmt1_ins->source << 8)
   4482 				      | (fmt1_ins->destination << 16)
   4483 				      |	(fmt1_ins->ret << 24)
   4484 				      |	(fmt1_ins->opcode << 25);
   4485 			}
   4486 		}
   4487 		instr.integer = htole32(instr.integer);
   4488 		ahc_outsb(ahc, SEQRAM, instr.bytes, 4);
   4489 		break;
   4490 	default:
   4491 		panic("Unknown opcode encountered in seq program");
   4492 		break;
   4493 	}
   4494 }
   4495 
   4496 static void
   4497 ahc_set_recoveryscb(struct ahc_softc *ahc, struct scb *scb)
   4498 {
   4499 
   4500 	if ((scb->flags & SCB_RECOVERY_SCB) == 0) {
   4501 		struct scb *scbp;
   4502 
   4503 		scb->flags |= SCB_RECOVERY_SCB;
   4504 
   4505 		/*
   4506 		 * Take all queued, but not sent SCBs out of the equation.
   4507 		 * Also ensure that no new CCBs are queued to us while we
   4508 		 * try to fix this problem.
   4509 		 */
   4510 		scsipi_channel_freeze(&ahc->sc_channel, 1);
   4511 		if (ahc->features & AHC_TWIN)
   4512 			scsipi_channel_freeze(&ahc->sc_channel_b, 1);
   4513 
   4514 		/*
   4515 		 * Go through all of our pending SCBs and remove
   4516 		 * any scheduled timeouts for them.  We will reschedule
   4517 		 * them after we've successfully fixed this problem.
   4518 		 */
   4519 		scbp = ahc->pending_ccbs.lh_first;
   4520 		while (scbp != NULL) {
   4521 			callout_stop(&scbp->xs->xs_callout);
   4522 			scbp = scbp->plinks.le_next;
   4523 		}
   4524 	}
   4525 }
   4526 
   4527 static void
   4528 ahc_timeout(void *arg)
   4529 {
   4530 	struct	scb *scb;
   4531 	struct	ahc_softc *ahc;
   4532 	int	s, found;
   4533 	u_int	last_phase;
   4534 	int	target;
   4535 	int	lun;
   4536 	int	i;
   4537 	char	channel;
   4538 
   4539 	scb = (struct scb *)arg;
   4540 	ahc =
   4541 	    (void *)scb->xs->xs_periph->periph_channel->chan_adapter->adapt_dev;
   4542 
   4543 	s = splbio();
   4544 
   4545 	/*
   4546 	 * Ensure that the card doesn't do anything
   4547 	 * behind our back.  Also make sure that we
   4548 	 * didn't "just" miss an interrupt that would
   4549 	 * affect this timeout.
   4550 	 */
   4551 	do {
   4552 		ahc_intr(ahc);
   4553 		pause_sequencer(ahc);
   4554 	} while (ahc_inb(ahc, INTSTAT) & INT_PEND);
   4555 
   4556 	if ((scb->flags & SCB_ACTIVE) == 0) {
   4557 		/* Previous timeout took care of me already */
   4558 		printf("Timedout SCB handled by another timeout\n");
   4559 		unpause_sequencer(ahc);
   4560 		splx(s);
   4561 		return;
   4562 	}
   4563 
   4564 	target = SCB_TARGET(scb);
   4565 	channel = SCB_CHANNEL(scb);
   4566 	lun = SCB_LUN(scb);
   4567 
   4568 	scsipi_printaddr(scb->xs->xs_periph);
   4569 	printf("SCB %x - timed out ", scb->hscb->tag);
   4570 	/*
   4571 	 * Take a snapshot of the bus state and print out
   4572 	 * some information so we can track down driver bugs.
   4573 	 */
   4574 	last_phase = ahc_inb(ahc, LASTPHASE);
   4575 
   4576 	for (i = 0; i < num_phases; i++) {
   4577 		if (last_phase == phase_table[i].phase)
   4578 			break;
   4579 	}
   4580 	printf("%s", phase_table[i].phasemsg);
   4581 
   4582 	printf(", SEQADDR == 0x%x\n",
   4583 	       ahc_inb(ahc, SEQADDR0) | (ahc_inb(ahc, SEQADDR1) << 8));
   4584 	printf("SCSIRATE == 0x%x\n", ahc_inb(ahc, SCSIRATE));
   4585 
   4586 #ifdef AHC_DEBUG
   4587 	ahc_print_scb(scb);
   4588 #endif
   4589 
   4590 #if 0
   4591 	printf("SSTAT1 == 0x%x\n", ahc_inb(ahc, SSTAT1));
   4592 	printf("SSTAT3 == 0x%x\n", ahc_inb(ahc, SSTAT3));
   4593 	printf("SCSIPHASE == 0x%x\n", ahc_inb(ahc, SCSIPHASE));
   4594 	printf("SCSIOFFSET == 0x%x\n", ahc_inb(ahc, SCSIOFFSET));
   4595 	printf("SEQ_FLAGS == 0x%x\n", ahc_inb(ahc, SEQ_FLAGS));
   4596 	printf("SCB_DATAPTR == 0x%x\n", ahc_inb(ahc, SCB_DATAPTR)
   4597 				      | ahc_inb(ahc, SCB_DATAPTR + 1) << 8
   4598 				      | ahc_inb(ahc, SCB_DATAPTR + 2) << 16
   4599 				      | ahc_inb(ahc, SCB_DATAPTR + 3) << 24);
   4600 	printf("SCB_DATACNT == 0x%x\n", ahc_inb(ahc, SCB_DATACNT)
   4601 				      | ahc_inb(ahc, SCB_DATACNT + 1) << 8
   4602 				      | ahc_inb(ahc, SCB_DATACNT + 2) << 16);
   4603 	printf("SCB_SGCOUNT == 0x%x\n", ahc_inb(ahc, SCB_SGCOUNT));
   4604 	printf("CCSCBCTL == 0x%x\n", ahc_inb(ahc, CCSCBCTL));
   4605 	printf("CCSCBCNT == 0x%x\n", ahc_inb(ahc, CCSCBCNT));
   4606 	printf("DFCNTRL == 0x%x\n", ahc_inb(ahc, DFCNTRL));
   4607 	printf("DFSTATUS == 0x%x\n", ahc_inb(ahc, DFSTATUS));
   4608 	printf("CCHCNT == 0x%x\n", ahc_inb(ahc, CCHCNT));
   4609 	if (scb->sg_count > 0) {
   4610 		for (i = 0; i < scb->sg_count; i++) {
   4611 			printf("sg[%d] - Addr 0x%x : Length %d\n",
   4612 			       i,
   4613 			       le32toh(scb->sg_list[i].addr),
   4614 			       le32toh(scb->sg_list[i].len));
   4615 		}
   4616 	}
   4617 #endif
   4618 	if (scb->flags & (SCB_DEVICE_RESET|SCB_ABORT)) {
   4619 		/*
   4620 		 * Been down this road before.
   4621 		 * Do a full bus reset.
   4622 		 */
   4623 bus_reset:
   4624 		ahcsetccbstatus(scb->xs, XS_TIMEOUT);
   4625 		found = ahc_reset_channel(ahc, channel, /*Initiate Reset*/TRUE);
   4626 		printf("%s: Issued Channel %c Bus Reset. "
   4627 		       "%d SCBs aborted\n", ahc_name(ahc), channel, found);
   4628 	} else {
   4629 		/*
   4630 		 * If we are a target, transition to bus free and report
   4631 		 * the timeout.
   4632 		 *
   4633 		 * The target/initiator that is holding up the bus may not
   4634 		 * be the same as the one that triggered this timeout
   4635 		 * (different commands have different timeout lengths).
   4636 		 * If the bus is idle and we are actiing as the initiator
   4637 		 * for this request, queue a BDR message to the timed out
   4638 		 * target.  Otherwise, if the timed out transaction is
   4639 		 * active:
   4640 		 *   Initiator transaction:
   4641 		 *	Stuff the message buffer with a BDR message and assert
   4642 		 *	ATN in the hopes that the target will let go of the bus
   4643 		 *	and go to the mesgout phase.  If this fails, we'll
   4644 		 *	get another timeout 2 seconds later which will attempt
   4645 		 *	a bus reset.
   4646 		 *
   4647 		 *   Target transaction:
   4648 		 *	Transition to BUS FREE and report the error.
   4649 		 *	It's good to be the target!
   4650 		 */
   4651 		u_int active_scb_index;
   4652 
   4653 		active_scb_index = ahc_inb(ahc, SCB_TAG);
   4654 
   4655 		if (last_phase != P_BUSFREE
   4656 		  && (active_scb_index < ahc->scb_data->numscbs)) {
   4657 			struct scb *active_scb;
   4658 
   4659 			/*
   4660 			 * If the active SCB is not from our device,
   4661 			 * assume that another device is hogging the bus
   4662 			 * and wait for it's timeout to expire before
   4663 			 * taking additional action.
   4664 			 */
   4665 			active_scb = &ahc->scb_data->scbarray[active_scb_index];
   4666 			if (active_scb->hscb->tcl != scb->hscb->tcl) {
   4667 				u_int	newtimeout;
   4668 
   4669 				scsipi_printaddr(scb->xs->xs_periph);
   4670 				printf("Other SCB Timeout%s",
   4671 			 	       (scb->flags & SCB_OTHERTCL_TIMEOUT) != 0
   4672 				       ? " again\n" : "\n");
   4673 				scb->flags |= SCB_OTHERTCL_TIMEOUT;
   4674 				newtimeout = MAX(active_scb->xs->timeout,
   4675 						 scb->xs->timeout);
   4676 				callout_reset(&scb->xs->xs_callout,
   4677 				    (newtimeout * hz) / 1000,
   4678 				    ahc_timeout, scb);
   4679 				splx(s);
   4680 				return;
   4681 			}
   4682 
   4683 			/* It's us */
   4684 			if ((scb->hscb->control & TARGET_SCB) != 0) {
   4685 
   4686 				/*
   4687 				 * Send back any queued up transactions
   4688 				 * and properly record the error condition.
   4689 				 */
   4690 				ahc_freeze_devq(ahc, scb->xs->xs_periph);
   4691 				ahcsetccbstatus(scb->xs, XS_TIMEOUT);
   4692 				ahc_freeze_ccb(scb);
   4693 				ahc_done(ahc, scb);
   4694 
   4695 				/* Will clear us from the bus */
   4696 				restart_sequencer(ahc);
   4697 				splx(s);
   4698 				return;
   4699 			}
   4700 
   4701 			ahc_set_recoveryscb(ahc, active_scb);
   4702 			ahc_outb(ahc, MSG_OUT, MSG_BUS_DEV_RESET);
   4703 			ahc_outb(ahc, SCSISIGO, last_phase|ATNO);
   4704 			scsipi_printaddr(active_scb->xs->xs_periph);
   4705 			printf("BDR message in message buffer\n");
   4706 			active_scb->flags |=  SCB_DEVICE_RESET;
   4707 			callout_reset(&active_scb->xs->xs_callout,
   4708 			    2 * hz, ahc_timeout, active_scb);
   4709 			unpause_sequencer(ahc);
   4710 		} else {
   4711 			int	 disconnected;
   4712 
   4713 			/* XXX Shouldn't panic.  Just punt instead */
   4714 			if ((scb->hscb->control & TARGET_SCB) != 0)
   4715 				panic("Timed-out target SCB but bus idle");
   4716 
   4717 			if (last_phase != P_BUSFREE
   4718 			 && (ahc_inb(ahc, SSTAT0) & TARGET) != 0) {
   4719 				/* XXX What happened to the SCB? */
   4720 				/* Hung target selection.  Goto busfree */
   4721 				printf("%s: Hung target selection\n",
   4722 				       ahc_name(ahc));
   4723 				restart_sequencer(ahc);
   4724 				splx(s);
   4725 				return;
   4726 			}
   4727 
   4728 			if (ahc_search_qinfifo(ahc, target, channel, lun,
   4729 					       scb->hscb->tag, ROLE_INITIATOR,
   4730 					       /*status*/0, SEARCH_COUNT) > 0) {
   4731 				disconnected = FALSE;
   4732 			} else {
   4733 				disconnected = TRUE;
   4734 			}
   4735 
   4736 			if (disconnected) {
   4737 				u_int active_scb;
   4738 
   4739 				ahc_set_recoveryscb(ahc, scb);
   4740 				/*
   4741 				 * Simply set the MK_MESSAGE control bit.
   4742 				 */
   4743 				scb->hscb->control |= MK_MESSAGE;
   4744 				scb->flags |= SCB_QUEUED_MSG
   4745 					   |  SCB_DEVICE_RESET;
   4746 
   4747 				/*
   4748 				 * Mark the cached copy of this SCB in the
   4749 				 * disconnected list too, so that a reconnect
   4750 				 * at this point causes a BDR or abort.
   4751 				 */
   4752 				active_scb = ahc_inb(ahc, SCBPTR);
   4753 				if (ahc_search_disc_list(ahc, target,
   4754 							 channel, lun,
   4755 							 scb->hscb->tag,
   4756 							 /*stop_on_first*/TRUE,
   4757 							 /*remove*/FALSE,
   4758 							 /*save_state*/FALSE)) {
   4759 					u_int scb_control;
   4760 
   4761 					scb_control = ahc_inb(ahc, SCB_CONTROL);
   4762 					scb_control |= MK_MESSAGE;
   4763 					ahc_outb(ahc, SCB_CONTROL, scb_control);
   4764 				}
   4765 				ahc_outb(ahc, SCBPTR, active_scb);
   4766 				ahc_index_busy_tcl(ahc, scb->hscb->tcl,
   4767 						   /*unbusy*/TRUE);
   4768 
   4769 				/*
   4770 				 * Actually re-queue this SCB in case we can
   4771 				 * select the device before it reconnects.
   4772 				 * Clear out any entries in the QINFIFO first
   4773 				 * so we are the next SCB for this target
   4774 				 * to run.
   4775 				 */
   4776 				ahc_search_qinfifo(ahc, SCB_TARGET(scb),
   4777 						   channel, SCB_LUN(scb),
   4778 						   SCB_LIST_NULL,
   4779 						   ROLE_INITIATOR,
   4780 						   SCB_REQUEUE,
   4781 						   SEARCH_COMPLETE);
   4782 				scsipi_printaddr(scb->xs->xs_periph);
   4783 				printf("Queuing a BDR SCB\n");
   4784 				ahc->qinfifo[ahc->qinfifonext++] =
   4785 				    scb->hscb->tag;
   4786 
   4787 				bus_dmamap_sync(ahc->parent_dmat,
   4788 				    ahc->shared_data_dmamap,
   4789 				    QINFIFO_OFFSET * 256, 256,
   4790 				    BUS_DMASYNC_PREWRITE);
   4791 
   4792 				if ((ahc->features & AHC_QUEUE_REGS) != 0) {
   4793 					ahc_outb(ahc, HNSCB_QOFF,
   4794 						 ahc->qinfifonext);
   4795 				} else {
   4796 					ahc_outb(ahc, KERNEL_QINPOS,
   4797 						 ahc->qinfifonext);
   4798 				}
   4799 				callout_reset(&scb->xs->xs_callout, 2 * hz,
   4800 				    ahc_timeout, scb);
   4801 				unpause_sequencer(ahc);
   4802 			} else {
   4803 				/* Go "immediatly" to the bus reset */
   4804 				/* This shouldn't happen */
   4805 				ahc_set_recoveryscb(ahc, scb);
   4806 				scsipi_printaddr(scb->xs->xs_periph);
   4807 				printf("SCB %x: Immediate reset.  "
   4808 					"Flags = 0x%x\n", scb->hscb->tag,
   4809 					scb->flags);
   4810 				goto bus_reset;
   4811 			}
   4812 		}
   4813 	}
   4814 	splx(s);
   4815 }
   4816 
   4817 static int
   4818 ahc_search_qinfifo(struct ahc_softc *ahc, int target, char channel,
   4819 		   int lun, u_int tag, role_t role, scb_flag status,
   4820 		   ahc_search_action action)
   4821 {
   4822 	struct	 scb *scbp;
   4823 	u_int8_t qinpos;
   4824 	u_int8_t qintail;
   4825 	int	 found;
   4826 
   4827 	qinpos = ahc_inb(ahc, QINPOS);
   4828 	qintail = ahc->qinfifonext;
   4829 	found = 0;
   4830 
   4831 	/*
   4832 	 * Start with an empty queue.  Entries that are not chosen
   4833 	 * for removal will be re-added to the queue as we go.
   4834 	 */
   4835 	ahc->qinfifonext = qinpos;
   4836 
   4837 	bus_dmamap_sync(ahc->parent_dmat, ahc->shared_data_dmamap,
   4838 	    QINFIFO_OFFSET * 256, 256, BUS_DMASYNC_POSTREAD);
   4839 
   4840 	while (qinpos != qintail) {
   4841 		scbp = &ahc->scb_data->scbarray[ahc->qinfifo[qinpos]];
   4842 		if (ahc_match_scb(scbp, target, channel, lun, tag, role)) {
   4843 			/*
   4844 			 * We found an scb that needs to be removed.
   4845 			 */
   4846 			switch (action) {
   4847 			case SEARCH_COMPLETE:
   4848 				if (!(scbp->xs->xs_status & XS_STS_DONE)) {
   4849 					scbp->flags |= status;
   4850 					scbp->xs->error = XS_NOERROR;
   4851 				}
   4852 				ahc_freeze_ccb(scbp);
   4853 				ahc_done(ahc, scbp);
   4854 				break;
   4855 			case SEARCH_COUNT:
   4856 				ahc->qinfifo[ahc->qinfifonext++] =
   4857 				    scbp->hscb->tag;
   4858 				break;
   4859 			case SEARCH_REMOVE:
   4860 				break;
   4861 			}
   4862 			found++;
   4863 		} else {
   4864 			ahc->qinfifo[ahc->qinfifonext++] = scbp->hscb->tag;
   4865 		}
   4866 		qinpos++;
   4867 	}
   4868 
   4869 	bus_dmamap_sync(ahc->parent_dmat, ahc->shared_data_dmamap,
   4870 	    QINFIFO_OFFSET * 256, 256, BUS_DMASYNC_PREWRITE);
   4871 
   4872 	if ((ahc->features & AHC_QUEUE_REGS) != 0) {
   4873 		ahc_outb(ahc, HNSCB_QOFF, ahc->qinfifonext);
   4874 	} else {
   4875 		ahc_outb(ahc, KERNEL_QINPOS, ahc->qinfifonext);
   4876 	}
   4877 
   4878 	return (found);
   4879 }
   4880 
   4881 /*
   4882  * Abort all SCBs that match the given description (target/channel/lun/tag),
   4883  * setting their status to the passed in status if the status has not already
   4884  * been modified from CAM_REQ_INPROG.  This routine assumes that the sequencer
   4885  * is paused before it is called.
   4886  */
   4887 static int
   4888 ahc_abort_scbs(struct ahc_softc *ahc, int target, char channel,
   4889 	       int lun, u_int tag, role_t role, int status)
   4890 {
   4891 	struct	scb *scbp;
   4892 	u_int	active_scb;
   4893 	int	i;
   4894 	int	found;
   4895 
   4896 	/* restore this when we're done */
   4897 	active_scb = ahc_inb(ahc, SCBPTR);
   4898 
   4899 	found = ahc_search_qinfifo(ahc, target, channel, lun, SCB_LIST_NULL,
   4900 				   role, SCB_REQUEUE, SEARCH_COMPLETE);
   4901 
   4902 	/*
   4903 	 * Search waiting for selection list.
   4904 	 */
   4905 	{
   4906 		u_int8_t next, prev;
   4907 
   4908 		next = ahc_inb(ahc, WAITING_SCBH);  /* Start at head of list. */
   4909 		prev = SCB_LIST_NULL;
   4910 
   4911 		while (next != SCB_LIST_NULL) {
   4912 			u_int8_t scb_index;
   4913 
   4914 			ahc_outb(ahc, SCBPTR, next);
   4915 			scb_index = ahc_inb(ahc, SCB_TAG);
   4916 			if (scb_index >= ahc->scb_data->numscbs) {
   4917 				panic("Waiting List inconsistency. "
   4918 				      "SCB index == %d, yet numscbs == %d.",
   4919 				      scb_index, ahc->scb_data->numscbs);
   4920 			}
   4921 			scbp = &ahc->scb_data->scbarray[scb_index];
   4922 			if (ahc_match_scb(scbp, target, channel,
   4923 					  lun, SCB_LIST_NULL, role)) {
   4924 
   4925 				next = ahc_abort_wscb(ahc, next, prev);
   4926 			} else {
   4927 
   4928 				prev = next;
   4929 				next = ahc_inb(ahc, SCB_NEXT);
   4930 			}
   4931 		}
   4932 	}
   4933 	/*
   4934 	 * Go through the disconnected list and remove any entries we
   4935 	 * have queued for completion, 0'ing their control byte too.
   4936 	 * We save the active SCB and restore it ourselves, so there
   4937 	 * is no reason for this search to restore it too.
   4938 	 */
   4939 	ahc_search_disc_list(ahc, target, channel, lun, tag,
   4940 			     /*stop_on_first*/FALSE, /*remove*/TRUE,
   4941 			     /*save_state*/FALSE);
   4942 
   4943 	/*
   4944 	 * Go through the hardware SCB array looking for commands that
   4945 	 * were active but not on any list.
   4946 	 */
   4947 	for(i = 0; i < ahc->scb_data->maxhscbs; i++) {
   4948 		u_int scbid;
   4949 
   4950 		ahc_outb(ahc, SCBPTR, i);
   4951 		scbid = ahc_inb(ahc, SCB_TAG);
   4952 		scbp = &ahc->scb_data->scbarray[scbid];
   4953 		if (scbid < ahc->scb_data->numscbs
   4954 		 && ahc_match_scb(scbp, target, channel, lun, tag, role))
   4955 			ahc_add_curscb_to_free_list(ahc);
   4956 	}
   4957 
   4958 	/*
   4959 	 * Go through the pending CCB list and look for
   4960 	 * commands for this target that are still active.
   4961 	 * These are other tagged commands that were
   4962 	 * disconnected when the reset occured.
   4963 	 */
   4964 	{
   4965 		struct scb *scb;
   4966 
   4967 		scb = ahc->pending_ccbs.lh_first;
   4968 		while (scb != NULL) {
   4969 			scbp = scb;
   4970 			scb = scb->plinks.le_next;
   4971 			if (ahc_match_scb(scbp, target, channel,
   4972 					  lun, tag, role)) {
   4973 				if (!(scbp->xs->xs_status & XS_STS_DONE))
   4974 					ahcsetccbstatus(scbp->xs, status);
   4975 				ahc_freeze_ccb(scbp);
   4976 				ahc_done(ahc, scbp);
   4977 				found++;
   4978 			}
   4979 		}
   4980 	}
   4981 	ahc_outb(ahc, SCBPTR, active_scb);
   4982 	return found;
   4983 }
   4984 
   4985 static int
   4986 ahc_search_disc_list(struct ahc_softc *ahc, int target, char channel,
   4987 		     int lun, u_int tag, int stop_on_first, int remove,
   4988 		     int save_state)
   4989 {
   4990 	struct	scb *scbp;
   4991 	u_int	next;
   4992 	u_int	prev;
   4993 	u_int	count;
   4994 	u_int	active_scb;
   4995 
   4996 	count = 0;
   4997 	next = ahc_inb(ahc, DISCONNECTED_SCBH);
   4998 	prev = SCB_LIST_NULL;
   4999 
   5000 	if (save_state) {
   5001 		/* restore this when we're done */
   5002 		active_scb = ahc_inb(ahc, SCBPTR);
   5003 	} else
   5004 		/* Silence compiler */
   5005 		active_scb = SCB_LIST_NULL;
   5006 
   5007 	while (next != SCB_LIST_NULL) {
   5008 		u_int scb_index;
   5009 
   5010 		ahc_outb(ahc, SCBPTR, next);
   5011 		scb_index = ahc_inb(ahc, SCB_TAG);
   5012 		if (scb_index >= ahc->scb_data->numscbs) {
   5013 			panic("Disconnected List inconsistency. "
   5014 			      "SCB index == %d, yet numscbs == %d.",
   5015 			      scb_index, ahc->scb_data->numscbs);
   5016 		}
   5017 		scbp = &ahc->scb_data->scbarray[scb_index];
   5018 		if (ahc_match_scb(scbp, target, channel, lun,
   5019 				  tag, ROLE_INITIATOR)) {
   5020 			count++;
   5021 			if (remove) {
   5022 				next =
   5023 				    ahc_rem_scb_from_disc_list(ahc, prev, next);
   5024 			} else {
   5025 				prev = next;
   5026 				next = ahc_inb(ahc, SCB_NEXT);
   5027 			}
   5028 			if (stop_on_first)
   5029 				break;
   5030 		} else {
   5031 			prev = next;
   5032 			next = ahc_inb(ahc, SCB_NEXT);
   5033 		}
   5034 	}
   5035 	if (save_state)
   5036 		ahc_outb(ahc, SCBPTR, active_scb);
   5037 	return (count);
   5038 }
   5039 
   5040 static u_int
   5041 ahc_rem_scb_from_disc_list(struct ahc_softc *ahc, u_int prev, u_int scbptr)
   5042 {
   5043 	u_int next;
   5044 
   5045 	ahc_outb(ahc, SCBPTR, scbptr);
   5046 	next = ahc_inb(ahc, SCB_NEXT);
   5047 
   5048 	ahc_outb(ahc, SCB_CONTROL, 0);
   5049 
   5050 	ahc_add_curscb_to_free_list(ahc);
   5051 
   5052 	if (prev != SCB_LIST_NULL) {
   5053 		ahc_outb(ahc, SCBPTR, prev);
   5054 		ahc_outb(ahc, SCB_NEXT, next);
   5055 	} else
   5056 		ahc_outb(ahc, DISCONNECTED_SCBH, next);
   5057 
   5058 	return (next);
   5059 }
   5060 
   5061 static void
   5062 ahc_add_curscb_to_free_list(struct ahc_softc *ahc)
   5063 {
   5064 	/* Invalidate the tag so that ahc_find_scb doesn't think it's active */
   5065 	ahc_outb(ahc, SCB_TAG, SCB_LIST_NULL);
   5066 
   5067 	ahc_outb(ahc, SCB_NEXT, ahc_inb(ahc, FREE_SCBH));
   5068 	ahc_outb(ahc, FREE_SCBH, ahc_inb(ahc, SCBPTR));
   5069 }
   5070 
   5071 /*
   5072  * Manipulate the waiting for selection list and return the
   5073  * scb that follows the one that we remove.
   5074  */
   5075 static u_int
   5076 ahc_abort_wscb(struct ahc_softc *ahc, u_int scbpos, u_int prev)
   5077 {
   5078 	u_int curscb, next;
   5079 
   5080 	/*
   5081 	 * Select the SCB we want to abort and
   5082 	 * pull the next pointer out of it.
   5083 	 */
   5084 	curscb = ahc_inb(ahc, SCBPTR);
   5085 	ahc_outb(ahc, SCBPTR, scbpos);
   5086 	next = ahc_inb(ahc, SCB_NEXT);
   5087 
   5088 	/* Clear the necessary fields */
   5089 	ahc_outb(ahc, SCB_CONTROL, 0);
   5090 
   5091 	ahc_add_curscb_to_free_list(ahc);
   5092 
   5093 	/* update the waiting list */
   5094 	if (prev == SCB_LIST_NULL) {
   5095 		/* First in the list */
   5096 		ahc_outb(ahc, WAITING_SCBH, next);
   5097 
   5098 		/*
   5099 		 * Ensure we aren't attempting to perform
   5100 		 * selection for this entry.
   5101 		 */
   5102 		ahc_outb(ahc, SCSISEQ, (ahc_inb(ahc, SCSISEQ) & ~ENSELO));
   5103 	} else {
   5104 		/*
   5105 		 * Select the scb that pointed to us
   5106 		 * and update its next pointer.
   5107 		 */
   5108 		ahc_outb(ahc, SCBPTR, prev);
   5109 		ahc_outb(ahc, SCB_NEXT, next);
   5110 	}
   5111 
   5112 	/*
   5113 	 * Point us back at the original scb position.
   5114 	 */
   5115 	ahc_outb(ahc, SCBPTR, curscb);
   5116 	return next;
   5117 }
   5118 
   5119 static void
   5120 ahc_clear_intstat(struct ahc_softc *ahc)
   5121 {
   5122 	/* Clear any interrupt conditions this may have caused */
   5123 	ahc_outb(ahc, CLRSINT0, CLRSELDO|CLRSELDI|CLRSELINGO);
   5124 	ahc_outb(ahc, CLRSINT1, CLRSELTIMEO|CLRATNO|CLRSCSIRSTI
   5125 				|CLRBUSFREE|CLRSCSIPERR|CLRPHASECHG|
   5126 				CLRREQINIT);
   5127 	ahc_outb(ahc, CLRINT, CLRSCSIINT);
   5128 }
   5129 
   5130 static void
   5131 ahc_reset_current_bus(struct ahc_softc *ahc)
   5132 {
   5133 	u_int8_t scsiseq;
   5134 
   5135 	ahc_outb(ahc, SIMODE1, ahc_inb(ahc, SIMODE1) & ~ENSCSIRST);
   5136 	scsiseq = ahc_inb(ahc, SCSISEQ);
   5137 	ahc_outb(ahc, SCSISEQ, scsiseq | SCSIRSTO);
   5138 	DELAY(AHC_BUSRESET_DELAY);
   5139 	/* Turn off the bus reset */
   5140 	ahc_outb(ahc, SCSISEQ, scsiseq & ~SCSIRSTO);
   5141 
   5142 	ahc_clear_intstat(ahc);
   5143 
   5144 	/* Re-enable reset interrupts */
   5145 	ahc_outb(ahc, SIMODE1, ahc_inb(ahc, SIMODE1) | ENSCSIRST);
   5146 }
   5147 
   5148 static int
   5149 ahc_reset_channel(struct ahc_softc *ahc, char channel, int initiate_reset)
   5150 {
   5151 	u_int	initiator, target, max_scsiid;
   5152 	u_int	sblkctl;
   5153 	u_int	our_id;
   5154 	int	found;
   5155 	int	restart_needed;
   5156 	char	cur_channel;
   5157 
   5158 	ahc->pending_device = NULL;
   5159 
   5160 	pause_sequencer(ahc);
   5161 
   5162 	/*
   5163 	 * Run our command complete fifos to ensure that we perform
   5164 	 * completion processing on any commands that 'completed'
   5165 	 * before the reset occurred.
   5166 	 */
   5167 	ahc_run_qoutfifo(ahc);
   5168 
   5169 	/*
   5170 	 * Reset the bus if we are initiating this reset
   5171 	 */
   5172 	sblkctl = ahc_inb(ahc, SBLKCTL);
   5173 	cur_channel = 'A';
   5174 	if ((ahc->features & AHC_TWIN) != 0
   5175 	 && ((sblkctl & SELBUSB) != 0))
   5176 	    cur_channel = 'B';
   5177 	if (cur_channel != channel) {
   5178 		/* Case 1: Command for another bus is active
   5179 		 * Stealthily reset the other bus without
   5180 		 * upsetting the current bus.
   5181 		 */
   5182 		ahc_outb(ahc, SBLKCTL, sblkctl ^ SELBUSB);
   5183 		ahc_outb(ahc, SIMODE1, ahc_inb(ahc, SIMODE1) & ~ENBUSFREE);
   5184 		ahc_outb(ahc, SCSISEQ,
   5185 			 ahc_inb(ahc, SCSISEQ) & (ENSELI|ENRSELI|ENAUTOATNP));
   5186 		if (initiate_reset)
   5187 			ahc_reset_current_bus(ahc);
   5188 		ahc_clear_intstat(ahc);
   5189 		ahc_outb(ahc, SBLKCTL, sblkctl);
   5190 		restart_needed = FALSE;
   5191 	} else {
   5192 		/* Case 2: A command from this bus is active or we're idle */
   5193 		ahc_clear_msg_state(ahc);
   5194 		ahc_outb(ahc, SIMODE1, ahc_inb(ahc, SIMODE1) & ~ENBUSFREE);
   5195 		ahc_outb(ahc, SCSISEQ,
   5196 			 ahc_inb(ahc, SCSISEQ) & (ENSELI|ENRSELI|ENAUTOATNP));
   5197 		if (initiate_reset)
   5198 			ahc_reset_current_bus(ahc);
   5199 		ahc_clear_intstat(ahc);
   5200 
   5201 		/*
   5202 		 * Since we are going to restart the sequencer, avoid
   5203 		 * a race in the sequencer that could cause corruption
   5204 		 * of our Q pointers by starting over from index 0.
   5205 		 */
   5206 		ahc->qoutfifonext = 0;
   5207 		if ((ahc->features & AHC_QUEUE_REGS) != 0)
   5208 			ahc_outb(ahc, SDSCB_QOFF, 0);
   5209 		else
   5210 			ahc_outb(ahc, QOUTPOS, 0);
   5211 		restart_needed = TRUE;
   5212 	}
   5213 
   5214 	/*
   5215 	 * Clean up all the state information for the
   5216 	 * pending transactions on this bus.
   5217 	 */
   5218 	found = ahc_abort_scbs(ahc, AHC_TARGET_WILDCARD, channel,
   5219 			       AHC_LUN_WILDCARD, SCB_LIST_NULL,
   5220 			       ROLE_UNKNOWN, XS_RESET);
   5221 	if (channel == 'B') {
   5222 		our_id = ahc->our_id_b;
   5223 	} else {
   5224 		our_id = ahc->our_id;
   5225 	}
   5226 
   5227 	max_scsiid = (ahc->features & AHC_WIDE) ? 15 : 7;
   5228 
   5229 	/*
   5230 	 * Revert to async/narrow transfers until we renegotiate.
   5231 	 */
   5232 	for (target = 0; target <= max_scsiid; target++) {
   5233 
   5234 		if (ahc->enabled_targets[target] == NULL)
   5235 			continue;
   5236 		for (initiator = 0; initiator <= max_scsiid; initiator++) {
   5237 			struct ahc_devinfo devinfo;
   5238 
   5239 			ahc_compile_devinfo(&devinfo, target, initiator,
   5240 					    AHC_LUN_WILDCARD,
   5241 					    channel, ROLE_UNKNOWN);
   5242 			ahc_set_width(ahc, &devinfo,
   5243 				      MSG_EXT_WDTR_BUS_8_BIT,
   5244 				      AHC_TRANS_CUR, /*paused*/TRUE, FALSE);
   5245 			ahc_set_syncrate(ahc, &devinfo,
   5246 					 /*syncrate*/NULL, /*period*/0,
   5247 					 /*offset*/0, AHC_TRANS_CUR,
   5248 					 /*paused*/TRUE, FALSE);
   5249 			ahc_update_xfer_mode(ahc, &devinfo);
   5250 		}
   5251 	}
   5252 
   5253 	if (restart_needed)
   5254 		restart_sequencer(ahc);
   5255 	else
   5256 		unpause_sequencer(ahc);
   5257 	return found;
   5258 }
   5259 
   5260 static int
   5261 ahc_match_scb(struct scb *scb, int target, char channel,
   5262 	      int lun, u_int tag, role_t role)
   5263 {
   5264 	int targ = SCB_TARGET(scb);
   5265 	char chan = SCB_CHANNEL(scb);
   5266 	int slun = SCB_LUN(scb);
   5267 	int match;
   5268 
   5269 	match = ((chan == channel) || (channel == ALL_CHANNELS));
   5270 	if (match != 0)
   5271 		match = ((targ == target) || (target == AHC_TARGET_WILDCARD));
   5272 	if (match != 0)
   5273 		match = ((lun == slun) || (lun == AHC_LUN_WILDCARD));
   5274 
   5275 	return match;
   5276 }
   5277 
   5278 static void
   5279 ahc_construct_sdtr(struct ahc_softc *ahc, u_int period, u_int offset)
   5280 {
   5281 	ahc->msgout_buf[ahc->msgout_index++] = MSG_EXTENDED;
   5282 	ahc->msgout_buf[ahc->msgout_index++] = MSG_EXT_SDTR_LEN;
   5283 	ahc->msgout_buf[ahc->msgout_index++] = MSG_EXT_SDTR;
   5284 	ahc->msgout_buf[ahc->msgout_index++] = period;
   5285 	ahc->msgout_buf[ahc->msgout_index++] = offset;
   5286 	ahc->msgout_len += 5;
   5287 }
   5288 
   5289 static void
   5290 ahc_construct_wdtr(struct ahc_softc *ahc, u_int bus_width)
   5291 {
   5292 	ahc->msgout_buf[ahc->msgout_index++] = MSG_EXTENDED;
   5293 	ahc->msgout_buf[ahc->msgout_index++] = MSG_EXT_WDTR_LEN;
   5294 	ahc->msgout_buf[ahc->msgout_index++] = MSG_EXT_WDTR;
   5295 	ahc->msgout_buf[ahc->msgout_index++] = bus_width;
   5296 	ahc->msgout_len += 4;
   5297 }
   5298 
   5299 static void
   5300 ahc_calc_residual(struct scb *scb)
   5301 {
   5302 	struct	hardware_scb *hscb;
   5303 
   5304 	hscb = scb->hscb;
   5305 
   5306 	/*
   5307 	 * If the disconnected flag is still set, this is bogus
   5308 	 * residual information left over from a sequencer
   5309 	 * pagin/pageout, so ignore this case.
   5310 	 */
   5311 	if ((scb->hscb->control & DISCONNECTED) == 0) {
   5312 		u_int32_t resid;
   5313 		int	  resid_sgs;
   5314 		int	  sg;
   5315 
   5316 		/*
   5317 		 * Remainder of the SG where the transfer
   5318 		 * stopped.
   5319 		 */
   5320 		resid = (hscb->residual_data_count[2] << 16)
   5321 		      |	(hscb->residual_data_count[1] <<8)
   5322 		      |	(hscb->residual_data_count[0]);
   5323 
   5324 		/*
   5325 		 * Add up the contents of all residual
   5326 		 * SG segments that are after the SG where
   5327 		 * the transfer stopped.
   5328 		 */
   5329 		resid_sgs = scb->hscb->residual_SG_count - 1/*current*/;
   5330 		sg = scb->sg_count - resid_sgs;
   5331 		while (resid_sgs > 0) {
   5332 
   5333 			resid += le32toh(scb->sg_list[sg].len);
   5334 			sg++;
   5335 			resid_sgs--;
   5336 		}
   5337 		scb->xs->resid = resid;
   5338 	}
   5339 
   5340 	/*
   5341 	 * Clean out the residual information in this SCB for its
   5342 	 * next consumer.
   5343 	 */
   5344 	hscb->residual_SG_count = 0;
   5345 
   5346 #ifdef AHC_DEBUG
   5347 	if (ahc_debug & AHC_SHOWMISC) {
   5348 		scsipi_printaddr(scb->xs->xs_periph);
   5349 		printf("Handled Residual of %ld bytes\n" ,(long)scb->xs->resid);
   5350 	}
   5351 #endif
   5352 }
   5353 
   5354 static void
   5355 ahc_update_pending_syncrates(struct ahc_softc *ahc)
   5356 {
   5357 	struct	scb *scb;
   5358 	int	pending_ccb_count;
   5359 	int	i;
   5360 	u_int	saved_scbptr;
   5361 
   5362 	/*
   5363 	 * Traverse the pending SCB list and ensure that all of the
   5364 	 * SCBs there have the proper settings.
   5365 	 */
   5366 	scb = LIST_FIRST(&ahc->pending_ccbs);
   5367 	pending_ccb_count = 0;
   5368 	while (scb != NULL) {
   5369 		struct ahc_devinfo devinfo;
   5370 		struct scsipi_xfer *xs;
   5371 		struct scb *pending_scb;
   5372 		struct hardware_scb *pending_hscb;
   5373 		struct ahc_initiator_tinfo *tinfo;
   5374 		struct tmode_tstate *tstate;
   5375 		u_int  our_id, remote_id;
   5376 
   5377 		xs = scb->xs;
   5378 		pending_scb = scb;
   5379 		pending_hscb = pending_scb->hscb;
   5380 		our_id = SCB_IS_SCSIBUS_B(pending_scb)
   5381 		       ? ahc->our_id_b : ahc->our_id;
   5382 		remote_id = xs->xs_periph->periph_target;
   5383 		ahc_compile_devinfo(&devinfo, our_id, remote_id,
   5384 				    SCB_LUN(pending_scb),
   5385 				    SCB_CHANNEL(pending_scb),
   5386 				    ROLE_UNKNOWN);
   5387 		tinfo = ahc_fetch_transinfo(ahc, devinfo.channel,
   5388 					    our_id, remote_id, &tstate);
   5389 		pending_hscb->control &= ~ULTRAENB;
   5390 		if ((tstate->ultraenb & devinfo.target_mask) != 0)
   5391 			pending_hscb->control |= ULTRAENB;
   5392 		pending_hscb->scsirate = tinfo->scsirate;
   5393 		pending_hscb->scsioffset = tinfo->current.offset;
   5394 		pending_ccb_count++;
   5395 		scb = LIST_NEXT(scb, plinks);
   5396 	}
   5397 
   5398 	if (pending_ccb_count == 0)
   5399 		return;
   5400 
   5401 	saved_scbptr = ahc_inb(ahc, SCBPTR);
   5402 	/* Ensure that the hscbs down on the card match the new information */
   5403 	for (i = 0; i < ahc->scb_data->maxhscbs; i++) {
   5404 		u_int scb_tag;
   5405 
   5406 		ahc_outb(ahc, SCBPTR, i);
   5407 		scb_tag = ahc_inb(ahc, SCB_TAG);
   5408 		if (scb_tag != SCB_LIST_NULL) {
   5409 			struct	ahc_devinfo devinfo;
   5410 			struct	scb *pending_scb;
   5411 			struct scsipi_xfer *xs;
   5412 			struct	hardware_scb *pending_hscb;
   5413 			struct	ahc_initiator_tinfo *tinfo;
   5414 			struct	tmode_tstate *tstate;
   5415 			u_int	our_id, remote_id;
   5416 			u_int	control;
   5417 
   5418 			pending_scb = &ahc->scb_data->scbarray[scb_tag];
   5419 			if (pending_scb->flags == SCB_FREE)
   5420 				continue;
   5421 			pending_hscb = pending_scb->hscb;
   5422 			xs = pending_scb->xs;
   5423 			our_id = SCB_IS_SCSIBUS_B(pending_scb)
   5424 			       ? ahc->our_id_b : ahc->our_id;
   5425 			remote_id = xs->xs_periph->periph_target;
   5426 			ahc_compile_devinfo(&devinfo, our_id, remote_id,
   5427 					    SCB_LUN(pending_scb),
   5428 					    SCB_CHANNEL(pending_scb),
   5429 					    ROLE_UNKNOWN);
   5430 			tinfo = ahc_fetch_transinfo(ahc, devinfo.channel,
   5431 						    our_id, remote_id, &tstate);
   5432 			control = ahc_inb(ahc, SCB_CONTROL);
   5433 			control &= ~ULTRAENB;
   5434 			if ((tstate->ultraenb & devinfo.target_mask) != 0)
   5435 				control |= ULTRAENB;
   5436 			ahc_outb(ahc, SCB_CONTROL, control);
   5437 			ahc_outb(ahc, SCB_SCSIRATE, tinfo->scsirate);
   5438 			ahc_outb(ahc, SCB_SCSIOFFSET, tinfo->current.offset);
   5439 		}
   5440 	}
   5441 	ahc_outb(ahc, SCBPTR, saved_scbptr);
   5442 }
   5443 
   5444 #if UNUSED
   5445 static void
   5446 ahc_dump_targcmd(struct target_cmd *cmd)
   5447 {
   5448 	u_int8_t *byte;
   5449 	u_int8_t *last_byte;
   5450 	int i;
   5451 
   5452 	byte = &cmd->initiator_channel;
   5453 	/* Debugging info for received commands */
   5454 	last_byte = &cmd[1].initiator_channel;
   5455 
   5456 	i = 0;
   5457 	while (byte < last_byte) {
   5458 		if (i == 0)
   5459 			printf("\t");
   5460 		printf("%#x", *byte++);
   5461 		i++;
   5462 		if (i == 8) {
   5463 			printf("\n");
   5464 			i = 0;
   5465 		} else {
   5466 			printf(", ");
   5467 		}
   5468 	}
   5469 }
   5470 #endif
   5471 
   5472 static void
   5473 ahc_shutdown(void *arg)
   5474 {
   5475 	struct	ahc_softc *ahc;
   5476 	int	i;
   5477 	u_int	sxfrctl1_a, sxfrctl1_b;
   5478 
   5479 	ahc = (struct ahc_softc *)arg;
   5480 
   5481 	pause_sequencer(ahc);
   5482 
   5483 	/*
   5484 	 * Preserve the value of the SXFRCTL1 register for all channels.
   5485 	 * It contains settings that affect termination and we don't want
   5486 	 * to disturb the integrity of the bus during shutdown in case
   5487 	 * we are in a multi-initiator setup.
   5488 	 */
   5489 	sxfrctl1_b = 0;
   5490 	if ((ahc->features & AHC_TWIN) != 0) {
   5491 		u_int sblkctl;
   5492 
   5493 		sblkctl = ahc_inb(ahc, SBLKCTL);
   5494 		ahc_outb(ahc, SBLKCTL, sblkctl | SELBUSB);
   5495 		sxfrctl1_b = ahc_inb(ahc, SXFRCTL1);
   5496 		ahc_outb(ahc, SBLKCTL, sblkctl & ~SELBUSB);
   5497 	}
   5498 
   5499 	sxfrctl1_a = ahc_inb(ahc, SXFRCTL1);
   5500 
   5501 	/* This will reset most registers to 0, but not all */
   5502 	ahc_reset(ahc);
   5503 
   5504 	if ((ahc->features & AHC_TWIN) != 0) {
   5505 		u_int sblkctl;
   5506 
   5507 		sblkctl = ahc_inb(ahc, SBLKCTL);
   5508 		ahc_outb(ahc, SBLKCTL, sblkctl | SELBUSB);
   5509 		ahc_outb(ahc, SXFRCTL1, sxfrctl1_b);
   5510 		ahc_outb(ahc, SBLKCTL, sblkctl & ~SELBUSB);
   5511 	}
   5512 	ahc_outb(ahc, SXFRCTL1, sxfrctl1_a);
   5513 
   5514 	ahc_outb(ahc, SCSISEQ, 0);
   5515 	ahc_outb(ahc, SXFRCTL0, 0);
   5516 	ahc_outb(ahc, DSPCISTATUS, 0);
   5517 
   5518 	for (i = TARG_SCSIRATE; i < HA_274_BIOSCTRL; i++)
   5519 		ahc_outb(ahc, i, 0);
   5520 }
   5521 
   5522 #if defined(AHC_DEBUG) && 0
   5523 static void
   5524 ahc_dumptinfo(struct ahc_softc *ahc, struct ahc_initiator_tinfo *tinfo)
   5525 {
   5526 	printf("%s: tinfo: rate %u\n", ahc_name(ahc), tinfo->scsirate);
   5527 
   5528 	printf("\tcurrent:\n");
   5529 	printf("\t\twidth %u period %u offset %u flags %x\n",
   5530 	    tinfo->current.width, tinfo->current.period,
   5531 	    tinfo->current.offset, tinfo->current.ppr_flags);
   5532 
   5533 	printf("\tgoal:\n");
   5534 	printf("\t\twidth %u period %u offset %u flags %x\n",
   5535 	    tinfo->goal.width, tinfo->goal.period,
   5536 	    tinfo->goal.offset, tinfo->goal.ppr_flags);
   5537 
   5538 	printf("\tuser:\n");
   5539 	printf("\t\twidth %u period %u offset %u flags %x\n",
   5540 	    tinfo->user.width, tinfo->user.period,
   5541 	    tinfo->user.offset, tinfo->user.ppr_flags);
   5542 }
   5543 #endif
   5544 
   5545 static int
   5546 ahc_istagged_device(struct ahc_softc *ahc, struct scsipi_xfer *xs,
   5547 		    int nocmdcheck)
   5548 {
   5549 #ifdef AHC_NO_TAGS
   5550 	return 0;
   5551 #else
   5552 	char channel;
   5553 	u_int our_id, target;
   5554 	struct tmode_tstate *tstate;
   5555 	struct ahc_devinfo devinfo;
   5556 
   5557 	channel = SIM_CHANNEL(ahc, xs->xs_periph);
   5558 	our_id = SIM_SCSI_ID(ahc, xs->xs_periph);
   5559 	target = xs->xs_periph->periph_target;
   5560 	(void)ahc_fetch_transinfo(ahc, channel, our_id, target, &tstate);
   5561 
   5562 	ahc_compile_devinfo(&devinfo, our_id, target,
   5563 	    xs->xs_periph->periph_lun, channel, ROLE_INITIATOR);
   5564 
   5565 	return (tstate->tagenable & devinfo.target_mask);
   5566 #endif
   5567 }
   5568