xref: /openbsd-src/sys/dev/ic/aic6360.c (revision f2da64fbbbf1b03f09f390ab01267c93dfd77c4c)
1 /*	$OpenBSD: aic6360.c,v 1.27 2014/09/14 14:17:24 jsg Exp $	*/
2 /*	$NetBSD: aic6360.c,v 1.52 1996/12/10 21:27:51 thorpej Exp $	*/
3 
4 #ifdef DDB
5 #define	integrate
6 #else
7 #define	integrate	static inline
8 #endif
9 
10 /*
11  * Copyright (c) 1994, 1995, 1996 Charles Hannum.  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  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. All advertising materials mentioning features or use of this software
22  *    must display the following acknowledgement:
23  *	This product includes software developed by Charles M. Hannum.
24  * 4. The name of the author may not be used to endorse or promote products
25  *    derived from this software without specific prior written permission.
26  *
27  * Copyright (c) 1994 Jarle Greipsland
28  * All rights reserved.
29  *
30  * Redistribution and use in source and binary forms, with or without
31  * modification, are permitted provided that the following conditions
32  * are met:
33  * 1. Redistributions of source code must retain the above copyright
34  *    notice, this list of conditions and the following disclaimer.
35  * 2. Redistributions in binary form must reproduce the above copyright
36  *    notice, this list of conditions and the following disclaimer in the
37  *    documentation and/or other materials provided with the distribution.
38  * 3. The name of the author may not be used to endorse or promote products
39  *    derived from this software without specific prior written permission.
40  *
41  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
42  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
43  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
44  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
45  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
46  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
47  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
50  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
51  * POSSIBILITY OF SUCH DAMAGE.
52  */
53 
54 /*
55  * Acknowledgements: Many of the algorithms used in this driver are
56  * inspired by the work of Julian Elischer (julian@tfs.com) and
57  * Charles Hannum (mycroft@duality.gnu.ai.mit.edu).  Thanks a million!
58  */
59 
60 /* TODO list:
61  * 1) Get the DMA stuff working.
62  * 2) Get the iov/uio stuff working. Is this a good thing ???
63  * 3) Get the synch stuff working.
64  * 4) Rewrite it to use malloc for the acb structs instead of static alloc.?
65  */
66 
67 /*
68  * A few customizable items:
69  */
70 
71 /* Use doubleword transfers to/from SCSI chip.  Note: This requires
72  * motherboard support.  Basicly, some motherboard chipsets are able to
73  * split a 32 bit I/O operation into two 16 bit I/O operations,
74  * transparently to the processor.  This speeds up some things, notably long
75  * data transfers.
76  */
77 #define AIC_USE_DWORDS		0
78 
79 /* Synchronous data transfers? */
80 #define AIC_USE_SYNCHRONOUS	0
81 #define AIC_SYNC_REQ_ACK_OFS 	8
82 
83 /* Wide data transfers? */
84 #define	AIC_USE_WIDE		0
85 #define	AIC_MAX_WIDTH		0
86 
87 /* Max attempts made to transmit a message */
88 #define AIC_MSG_MAX_ATTEMPT	3 /* Not used now XXX */
89 
90 /* Use DMA (else we do programmed I/O using string instructions) (not yet!)*/
91 #define AIC_USE_EISA_DMA	0
92 #define AIC_USE_ISA_DMA		0
93 
94 /* How to behave on the (E)ISA bus when/if DMAing (on<<4) + off in us */
95 #define EISA_BRST_TIM ((15<<4) + 1)	/* 15us on, 1us off */
96 
97 /* Some spin loop parameters (essentially how long to wait some places)
98  * The problem(?) is that sometimes we expect either to be able to transmit a
99  * byte or to get a new one from the SCSI bus pretty soon.  In order to avoid
100  * returning from the interrupt just to get yanked back for the next byte we
101  * may spin in the interrupt routine waiting for this byte to come.  How long?
102  * This is really (SCSI) device and processor dependent.  Tuneable, I guess.
103  */
104 #define AIC_MSGIN_SPIN		1 	/* Spin upto ?ms for a new msg byte */
105 #define AIC_MSGOUT_SPIN		1
106 
107 /* Include debug functions?  At the end of this file there are a bunch of
108  * functions that will print out various information regarding queued SCSI
109  * commands, driver state and chip contents.  You can call them from the
110  * kernel debugger.  If you set AIC_DEBUG to 0 they are not included (the
111  * kernel uses less memory) but you lose the debugging facilities.
112  */
113 #ifndef SMALL_KERNEL
114 #define AIC_DEBUG		1
115 #endif
116 
117 #define	AIC_ABORT_TIMEOUT	2000	/* time to wait for abort */
118 
119 /* End of customizable parameters */
120 
121 #if AIC_USE_EISA_DMA || AIC_USE_ISA_DMA
122 #error "I said not yet! Start paying attention... grumble"
123 #endif
124 
125 #include <sys/types.h>
126 #include <sys/param.h>
127 #include <sys/systm.h>
128 #include <sys/kernel.h>
129 #include <sys/errno.h>
130 #include <sys/ioctl.h>
131 #include <sys/device.h>
132 #include <sys/buf.h>
133 #include <sys/queue.h>
134 
135 #include <machine/bus.h>
136 #include <machine/intr.h>
137 
138 #include <scsi/scsi_all.h>
139 #include <scsi/scsi_message.h>
140 #include <scsi/scsiconf.h>
141 
142 #include <dev/isa/isavar.h>
143 
144 #include <dev/ic/aic6360reg.h>
145 #include <dev/ic/aic6360var.h>
146 
147 #ifndef DDB
148 #define	Debugger() panic("should call debugger here (aic6360.c)")
149 #endif /* ! DDB */
150 
151 #ifdef AIC_DEBUG
152 int aic_debug = 0x00; /* AIC_SHOWSTART|AIC_SHOWMISC|AIC_SHOWTRACE; */
153 #endif
154 
155 void	aic_minphys(struct buf *, struct scsi_link *);
156 void 	aic_init(struct aic_softc *);
157 void	aic_done(struct aic_softc *, struct aic_acb *);
158 void	aic_dequeue(struct aic_softc *, struct aic_acb *);
159 void	aic_scsi_cmd(struct scsi_xfer *);
160 int	aic_poll(struct aic_softc *, struct scsi_xfer *, int);
161 integrate void	aic_sched_msgout(struct aic_softc *, u_char);
162 integrate void	aic_setsync(struct aic_softc *, struct aic_tinfo *);
163 void	aic_select(struct aic_softc *, struct aic_acb *);
164 void	aic_timeout(void *);
165 void	aic_sched(struct aic_softc *);
166 void	aic_scsi_reset(struct aic_softc *);
167 void	aic_reset(struct aic_softc *);
168 void	aic_acb_free(void *, void *);
169 void	*aic_acb_alloc(void *);
170 int	aic_reselect(struct aic_softc *, int);
171 void	aic_sense(struct aic_softc *, struct aic_acb *);
172 void	aic_msgin(struct aic_softc *);
173 void	aic_abort(struct aic_softc *, struct aic_acb *);
174 void	aic_msgout(struct aic_softc *);
175 int	aic_dataout_pio(struct aic_softc *, u_char *, int);
176 int	aic_datain_pio(struct aic_softc *, u_char *, int);
177 #ifdef AIC_DEBUG
178 void	aic_print_acb(struct aic_acb *);
179 void	aic_dump_driver(struct aic_softc *);
180 void	aic_dump6360(struct aic_softc *);
181 void	aic_show_scsi_cmd(struct aic_acb *);
182 void	aic_print_active_acb(void);
183 #endif
184 
185 struct cfdriver aic_cd = {
186 	NULL, "aic", DV_DULL
187 };
188 
189 struct scsi_adapter aic_switch = {
190 	aic_scsi_cmd,
191 #ifdef notyet
192 	aic_minphys,
193 #else
194 	scsi_minphys,
195 #endif
196 	0,
197 	0,
198 };
199 
200 /*
201  * Do the real search-for-device.
202  */
203 int
204 aic_find(bus_space_tag_t iot, bus_space_handle_t ioh)
205 {
206 	char chip_id[sizeof(IDSTRING)];	/* For chips that support it */
207 	int i;
208 
209 	/* Remove aic6360 from possible powerdown mode */
210 	bus_space_write_1(iot, ioh, DMACNTRL0, 0);
211 
212 	/* Thanks to mark@aggregate.com for the new method for detecting
213 	 * whether the chip is present or not.  Bonus: may also work for
214 	 * the AIC-6260!
215  	 */
216 	AIC_TRACE(("aic: probing for aic-chip\n"));
217  	/*
218  	 * Linux also init's the stack to 1-16 and then clears it,
219      	 *  6260's don't appear to have an ID reg - mpg
220  	 */
221 	/* Push the sequence 0,1,..,15 on the stack */
222 #define STSIZE 16
223 	bus_space_write_1(iot, ioh, DMACNTRL1, 0); /* Reset stack pointer */
224 	for (i = 0; i < STSIZE; i++)
225 		bus_space_write_1(iot, ioh, STACK, i);
226 
227 	/* See if we can pull out the same sequence */
228 	bus_space_write_1(iot, ioh, DMACNTRL1, 0);
229  	for (i = 0; i < STSIZE && bus_space_read_1(iot, ioh, STACK) == i; i++)
230 		;
231 	if (i != STSIZE) {
232 		AIC_START(("STACK futzed at %d.\n", i));
233 		return (0);
234 	}
235 
236 	/* See if we can pull the id string out of the ID register,
237 	 * now only used for informational purposes.
238 	 */
239 	bzero(chip_id, sizeof(chip_id));
240 	bus_space_read_multi_1(iot, ioh, ID, chip_id, sizeof(IDSTRING) - 1);
241 	AIC_START(("AIC ID: %s ", chip_id));
242 	AIC_START(("chip revision %d\n",
243 	    (int)bus_space_read_1(iot, ioh, REV)));
244 
245 	return (1);
246 }
247 
248 /*
249  * Attach the AIC6360, fill out some high and low level data structures
250  */
251 void
252 aicattach(struct aic_softc *sc)
253 {
254 	struct scsibus_attach_args saa;
255 	AIC_TRACE(("aicattach  "));
256 	sc->sc_state = AIC_INIT;
257 
258 	sc->sc_initiator = 7;
259 	sc->sc_freq = 20;	/* XXXX assume 20 MHz. */
260 
261 	/*
262 	 * These are the bounds of the sync period, based on the frequency of
263 	 * the chip's clock input and the size and offset of the sync period
264 	 * register.
265 	 *
266 	 * For a 20MHz clock, this gives us 25, or 100nS, or 10MB/s, as a
267 	 * maximum transfer rate, and 112.5, or 450nS, or 2.22MB/s, as a
268 	 * minimum transfer rate.
269 	 */
270 	sc->sc_minsync = (2 * 250) / sc->sc_freq;
271 	sc->sc_maxsync = (9 * 250) / sc->sc_freq;
272 
273 	aic_init(sc);	/* init chip and driver */
274 
275 	/*
276 	 * Fill in the prototype scsi_link
277 	 */
278 	sc->sc_link.adapter_softc = sc;
279 	sc->sc_link.adapter_target = sc->sc_initiator;
280 	sc->sc_link.adapter = &aic_switch;
281 	sc->sc_link.openings = 2;
282 	sc->sc_link.pool = &sc->sc_iopool;
283 
284 	bzero(&saa, sizeof(saa));
285 	saa.saa_sc_link = &sc->sc_link;
286 
287 	config_found(&sc->sc_dev, &saa, scsiprint);
288 }
289 
290 int
291 aic_detach(struct device *self, int flags)
292 {
293 	struct aic_softc *sc = (struct aic_softc *) self;
294 	int rv = 0;
295 
296 	rv = config_detach_children(&sc->sc_dev, flags);
297 
298 	return (rv);
299 }
300 
301 /* Initialize AIC6360 chip itself
302  * The following conditions should hold:
303  * aicprobe should have succeeded, i.e. the ioh handle in aic_softc must
304  * be valid.
305  */
306 void
307 aic_reset(struct aic_softc *sc)
308 {
309 	bus_space_tag_t iot = sc->sc_iot;
310 	bus_space_handle_t ioh = sc->sc_ioh;
311 
312 	/*
313 	 * Doc. recommends to clear these two registers before operations
314 	 * commence
315 	 */
316 	bus_space_write_1(iot, ioh, SCSITEST, 0);
317 	bus_space_write_1(iot, ioh, TEST, 0);
318 
319 	/* Reset SCSI-FIFO and abort any transfers */
320 	bus_space_write_1(iot, ioh, SXFRCTL0, CHEN | CLRCH | CLRSTCNT);
321 
322 	/* Reset DMA-FIFO */
323 	bus_space_write_1(iot, ioh, DMACNTRL0, RSTFIFO);
324 	bus_space_write_1(iot, ioh, DMACNTRL1, 0);
325 
326 	/* Disable all selection features */
327 	bus_space_write_1(iot, ioh, SCSISEQ, 0);
328 	bus_space_write_1(iot, ioh, SXFRCTL1, 0);
329 
330 	/* Disable some interrupts */
331 	bus_space_write_1(iot, ioh, SIMODE0, 0x00);
332 	/* Clear a slew of interrupts */
333 	bus_space_write_1(iot, ioh, CLRSINT0, 0x7f);
334 
335 	/* Disable some more interrupts */
336 	bus_space_write_1(iot, ioh, SIMODE1, 0x00);
337 	/* Clear another slew of interrupts */
338 	bus_space_write_1(iot, ioh, CLRSINT1, 0xef);
339 
340 	/* Disable synchronous transfers */
341 	bus_space_write_1(iot, ioh, SCSIRATE, 0);
342 
343 	/* Haven't seen ant errors (yet) */
344 	bus_space_write_1(iot, ioh, CLRSERR, 0x07);
345 
346 	/* Set our SCSI-ID */
347 	bus_space_write_1(iot, ioh, SCSIID, sc->sc_initiator << OID_S);
348 	bus_space_write_1(iot, ioh, BRSTCNTRL, EISA_BRST_TIM);
349 }
350 
351 /* Pull the SCSI RST line for 500 us */
352 void
353 aic_scsi_reset(struct aic_softc *sc)
354 {
355 	bus_space_tag_t iot = sc->sc_iot;
356 	bus_space_handle_t ioh = sc->sc_ioh;
357 
358 	bus_space_write_1(iot, ioh, SCSISEQ, SCSIRSTO);
359 	delay(500);
360 	bus_space_write_1(iot, ioh, SCSISEQ, 0);
361 	delay(50);
362 }
363 
364 /*
365  * Initialize aic SCSI driver.
366  */
367 void
368 aic_init(struct aic_softc *sc)
369 {
370 	bus_space_tag_t iot = sc->sc_iot;
371 	bus_space_handle_t ioh = sc->sc_ioh;
372 	struct aic_acb *acb;
373 	int r;
374 
375 	aic_reset(sc);
376 	aic_scsi_reset(sc);
377 	aic_reset(sc);
378 
379 	if (sc->sc_state == AIC_INIT) {
380 		/* First time through; initialize. */
381 		TAILQ_INIT(&sc->ready_list);
382 		TAILQ_INIT(&sc->nexus_list);
383 		TAILQ_INIT(&sc->free_list);
384 		mtx_init(&sc->sc_acb_mtx, IPL_BIO);
385 		scsi_iopool_init(&sc->sc_iopool, sc, aic_acb_alloc,
386 		    aic_acb_free);
387 		sc->sc_nexus = NULL;
388 		acb = sc->sc_acb;
389 		bzero(acb, sizeof(sc->sc_acb));
390 		for (r = 0; r < sizeof(sc->sc_acb) / sizeof(*acb); r++) {
391 			TAILQ_INSERT_TAIL(&sc->free_list, acb, chain);
392 			acb++;
393 		}
394 		bzero(&sc->sc_tinfo, sizeof(sc->sc_tinfo));
395 	} else {
396 		/* Cancel any active commands. */
397 		sc->sc_state = AIC_CLEANING;
398 		if ((acb = sc->sc_nexus) != NULL) {
399 			acb->xs->error = XS_DRIVER_STUFFUP;
400 			timeout_del(&acb->xs->stimeout);
401 			aic_done(sc, acb);
402 		}
403 		while ((acb = TAILQ_FIRST(&sc->nexus_list)) != NULL) {
404 			acb->xs->error = XS_DRIVER_STUFFUP;
405 			timeout_del(&acb->xs->stimeout);
406 			aic_done(sc, acb);
407 		}
408 	}
409 
410 	sc->sc_prevphase = PH_INVALID;
411 	for (r = 0; r < 8; r++) {
412 		struct aic_tinfo *ti = &sc->sc_tinfo[r];
413 
414 		ti->flags = 0;
415 #if AIC_USE_SYNCHRONOUS
416 		ti->flags |= DO_SYNC;
417 		ti->period = sc->sc_minsync;
418 		ti->offset = AIC_SYNC_REQ_ACK_OFS;
419 #else
420 		ti->period = ti->offset = 0;
421 #endif
422 #if AIC_USE_WIDE
423 		ti->flags |= DO_WIDE;
424 		ti->width = AIC_MAX_WIDTH;
425 #else
426 		ti->width = 0;
427 #endif
428 	}
429 
430 	sc->sc_state = AIC_IDLE;
431 	bus_space_write_1(iot, ioh, DMACNTRL0, INTEN);
432 }
433 
434 void
435 aic_acb_free(void *xsc, void *xacb)
436 {
437 	struct aic_softc *sc = xsc;
438 	struct aic_acb *acb = xacb;
439 
440 	mtx_enter(&sc->sc_acb_mtx);
441 	acb->flags = 0;
442 	TAILQ_INSERT_HEAD(&sc->free_list, acb, chain);
443 	mtx_leave(&sc->sc_acb_mtx);
444 }
445 
446 void *
447 aic_acb_alloc(void *xsc)
448 {
449 	struct aic_softc *sc = xsc;
450 	struct aic_acb *acb;
451 
452 	mtx_enter(&sc->sc_acb_mtx);
453 	acb = TAILQ_FIRST(&sc->free_list);
454 	if (acb) {
455 		TAILQ_REMOVE(&sc->free_list, acb, chain);
456 		acb->flags |= ACB_ALLOC;
457 	}
458 	mtx_leave(&sc->sc_acb_mtx);
459 
460 	return acb;
461 }
462 
463 /*
464  * DRIVER FUNCTIONS CALLABLE FROM HIGHER LEVEL DRIVERS
465  */
466 
467 /*
468  * Expected sequence:
469  * 1) Command inserted into ready list
470  * 2) Command selected for execution
471  * 3) Command won arbitration and has selected target device
472  * 4) Send message out (identify message, eventually also sync.negotiations)
473  * 5) Send command
474  * 5a) Receive disconnect message, disconnect.
475  * 5b) Reselected by target
476  * 5c) Receive identify message from target.
477  * 6) Send or receive data
478  * 7) Receive status
479  * 8) Receive message (command complete etc.)
480  * 9) If status == SCSI_CHECK construct a synthetic request sense SCSI cmd.
481  *    Repeat 2-8 (no disconnects please...)
482  */
483 
484 /*
485  * Start a SCSI-command
486  * This function is called by the higher level SCSI-driver to queue/run
487  * SCSI-commands.
488  */
489 void
490 aic_scsi_cmd(struct scsi_xfer *xs)
491 {
492 	struct scsi_link *sc_link = xs->sc_link;
493 	struct aic_softc *sc = sc_link->adapter_softc;
494 	struct aic_acb *acb;
495 	int s, flags;
496 
497 	AIC_TRACE(("aic_scsi_cmd  "));
498 	AIC_CMDS(("[0x%x, %d]->%d ", (int)xs->cmd->opcode, xs->cmdlen,
499 	    sc_link->target));
500 
501 	flags = xs->flags;
502 	acb = xs->io;
503 
504 	/* Initialize acb */
505 	acb->xs = xs;
506 	acb->timeout = xs->timeout;
507 	timeout_set(&xs->stimeout, aic_timeout, acb);
508 
509 	if (xs->flags & SCSI_RESET) {
510 		acb->flags |= ACB_RESET;
511 		acb->scsi_cmd_length = 0;
512 		acb->data_length = 0;
513 	} else {
514 		bcopy(xs->cmd, &acb->scsi_cmd, xs->cmdlen);
515 		acb->scsi_cmd_length = xs->cmdlen;
516 		acb->data_addr = xs->data;
517 		acb->data_length = xs->datalen;
518 	}
519 	acb->target_stat = 0;
520 
521 	s = splbio();
522 
523 	TAILQ_INSERT_TAIL(&sc->ready_list, acb, chain);
524 	if (sc->sc_state == AIC_IDLE)
525 		aic_sched(sc);
526 
527 	splx(s);
528 
529 	if ((flags & SCSI_POLL) == 0)
530 		return;
531 
532 	/* Not allowed to use interrupts, use polling instead */
533 	if (aic_poll(sc, xs, acb->timeout)) {
534 		aic_timeout(acb);
535 		if (aic_poll(sc, xs, acb->timeout))
536 			aic_timeout(acb);
537 	}
538 }
539 
540 #ifdef notyet
541 /*
542  * Adjust transfer size in buffer structure
543  */
544 void
545 aic_minphys(struct buf *bp, struct scsi_link *sl)
546 {
547 
548 	AIC_TRACE(("aic_minphys  "));
549 	if (bp->b_bcount > (AIC_NSEG << PGSHIFT))
550 		bp->b_bcount = (AIC_NSEG << PGSHIFT);
551 	minphys(bp);
552 }
553 #endif
554 
555 /*
556  * Used when interrupt driven I/O isn't allowed, e.g. during boot.
557  */
558 int
559 aic_poll(struct aic_softc *sc, struct scsi_xfer *xs, int count)
560 {
561 	bus_space_tag_t iot = sc->sc_iot;
562 	bus_space_handle_t ioh = sc->sc_ioh;
563 	int s;
564 
565 	AIC_TRACE(("aic_poll  "));
566 	while (count) {
567 		/*
568 		 * If we had interrupts enabled, would we
569 		 * have got an interrupt?
570 		 */
571 		if ((bus_space_read_1(iot, ioh, DMASTAT) & INTSTAT) != 0) {
572 			s = splbio();
573 			aicintr(sc);
574 			splx(s);
575 		}
576 		if ((xs->flags & ITSDONE) != 0)
577 			return 0;
578 		delay(1000);
579 		count--;
580 	}
581 	return 1;
582 }
583 
584 /*
585  * LOW LEVEL SCSI UTILITIES
586  */
587 
588 integrate void
589 aic_sched_msgout(struct aic_softc *sc, u_char m)
590 {
591 	bus_space_tag_t iot = sc->sc_iot;
592 	bus_space_handle_t ioh = sc->sc_ioh;
593 
594 	if (sc->sc_msgpriq == 0)
595 		bus_space_write_1(iot, ioh, SCSISIG, sc->sc_phase | ATNO);
596 	sc->sc_msgpriq |= m;
597 }
598 
599 /*
600  * Set synchronous transfer offset and period.
601  */
602 integrate void
603 aic_setsync(struct aic_softc *sc, struct aic_tinfo *ti)
604 {
605 #if AIC_USE_SYNCHRONOUS
606 	bus_space_tag_t iot = sc->sc_iot;
607 	bus_space_handle_t ioh = sc->sc_ioh;
608 
609 	if (ti->offset != 0)
610 		bus_space_write_1(iot, ioh, SCSIRATE,
611 		    ((ti->period * sc->sc_freq) / 250 - 2) << 4 | ti->offset);
612 	else
613 		bus_space_write_1(iot, ioh, SCSIRATE, 0);
614 #endif
615 }
616 
617 /*
618  * Start a selection.  This is used by aic_sched() to select an idle target,
619  * and by aic_done() to immediately reselect a target to get sense information.
620  */
621 void
622 aic_select(struct aic_softc *sc, struct aic_acb *acb)
623 {
624 	bus_space_tag_t iot = sc->sc_iot;
625 	bus_space_handle_t ioh = sc->sc_ioh;
626 	struct scsi_link *sc_link = acb->xs->sc_link;
627 	int target = sc_link->target;
628 	struct aic_tinfo *ti = &sc->sc_tinfo[target];
629 
630 	bus_space_write_1(iot, ioh, SCSIID,
631 	    sc->sc_initiator << OID_S | target);
632 	aic_setsync(sc, ti);
633 	bus_space_write_1(iot, ioh, SXFRCTL1, STIMO_256ms | ENSTIMER);
634 
635 	/* Always enable reselections. */
636 	bus_space_write_1(iot, ioh, SIMODE0, ENSELDI | ENSELDO);
637 	bus_space_write_1(iot, ioh, SIMODE1, ENSCSIRST | ENSELTIMO);
638 	bus_space_write_1(iot, ioh, SCSISEQ, ENRESELI | ENSELO | ENAUTOATNO);
639 
640 	sc->sc_state = AIC_SELECTING;
641 }
642 
643 int
644 aic_reselect(struct aic_softc *sc, int message)
645 {
646 	u_char selid, target, lun;
647 	struct aic_acb *acb;
648 	struct scsi_link *sc_link;
649 	struct aic_tinfo *ti;
650 
651 	/*
652 	 * The SCSI chip made a snapshot of the data bus while the reselection
653 	 * was being negotiated.  This enables us to determine which target did
654 	 * the reselect.
655 	 */
656 	selid = sc->sc_selid & ~(1 << sc->sc_initiator);
657 	if (selid & (selid - 1)) {
658 		printf("%s: reselect with invalid selid %02x; ",
659 		    sc->sc_dev.dv_xname, selid);
660 		printf("sending DEVICE RESET\n");
661 		AIC_BREAK();
662 		goto reset;
663 	}
664 
665 	/* Search wait queue for disconnected cmd
666 	 * The list should be short, so I haven't bothered with
667 	 * any more sophisticated structures than a simple
668 	 * singly linked list.
669 	 */
670 	target = ffs(selid) - 1;
671 	lun = message & 0x07;
672 	TAILQ_FOREACH(acb, &sc->nexus_list, chain) {
673 		sc_link = acb->xs->sc_link;
674 		if (sc_link->target == target && sc_link->lun == lun)
675 			break;
676 	}
677 	if (acb == NULL) {
678 		printf("%s: reselect from target %d lun %d with no nexus; ",
679 		    sc->sc_dev.dv_xname, target, lun);
680 		printf("sending ABORT\n");
681 		AIC_BREAK();
682 		goto abort;
683 	}
684 
685 	/* Make this nexus active again. */
686 	TAILQ_REMOVE(&sc->nexus_list, acb, chain);
687 	sc->sc_state = AIC_CONNECTED;
688 	sc->sc_nexus = acb;
689 	ti = &sc->sc_tinfo[target];
690 	ti->lubusy |= (1 << lun);
691 	aic_setsync(sc, ti);
692 
693 	if (acb->flags & ACB_RESET)
694 		aic_sched_msgout(sc, SEND_DEV_RESET);
695 	else if (acb->flags & ACB_ABORT)
696 		aic_sched_msgout(sc, SEND_ABORT);
697 
698 	/* Do an implicit RESTORE POINTERS. */
699 	sc->sc_dp = acb->data_addr;
700 	sc->sc_dleft = acb->data_length;
701 	sc->sc_cp = (u_char *)&acb->scsi_cmd;
702 	sc->sc_cleft = acb->scsi_cmd_length;
703 
704 	return (0);
705 
706 reset:
707 	aic_sched_msgout(sc, SEND_DEV_RESET);
708 	return (1);
709 
710 abort:
711 	aic_sched_msgout(sc, SEND_ABORT);
712 	return (1);
713 }
714 
715 /*
716  * Schedule a SCSI operation.  This has now been pulled out of the interrupt
717  * handler so that we may call it from aic_scsi_cmd and aic_done.  This may
718  * save us an unnecessary interrupt just to get things going.  Should only be
719  * called when state == AIC_IDLE and at bio pl.
720  */
721 void
722 aic_sched(struct aic_softc *sc)
723 {
724 	bus_space_tag_t iot = sc->sc_iot;
725 	bus_space_handle_t ioh = sc->sc_ioh;
726 	struct aic_acb *acb;
727 	struct scsi_link *sc_link;
728 	struct aic_tinfo *ti;
729 
730 	/*
731 	 * Find first acb in ready queue that is for a target/lunit pair that
732 	 * is not busy.
733 	 */
734 	bus_space_write_1(iot, ioh, CLRSINT1,
735 	    CLRSELTIMO | CLRBUSFREE | CLRSCSIPERR);
736 	TAILQ_FOREACH(acb, &sc->ready_list, chain) {
737 		sc_link = acb->xs->sc_link;
738 		ti = &sc->sc_tinfo[sc_link->target];
739 		if ((ti->lubusy & (1 << sc_link->lun)) == 0) {
740 			AIC_MISC(("selecting %d:%d  ",
741 			    sc_link->target, sc_link->lun));
742 			TAILQ_REMOVE(&sc->ready_list, acb, chain);
743 			sc->sc_nexus = acb;
744 			aic_select(sc, acb);
745 			return;
746 		} else
747 			AIC_MISC(("%d:%d busy\n",
748 			    sc_link->target, sc_link->lun));
749 	}
750 	AIC_MISC(("idle  "));
751 	/* Nothing to start; just enable reselections and wait. */
752 	bus_space_write_1(iot, ioh, SIMODE0, ENSELDI);
753 	bus_space_write_1(iot, ioh, SIMODE1, ENSCSIRST);
754 	bus_space_write_1(iot, ioh, SCSISEQ, ENRESELI);
755 }
756 
757 void
758 aic_sense(struct aic_softc *sc, struct aic_acb *acb)
759 {
760 	struct scsi_xfer *xs = acb->xs;
761 	struct scsi_link *sc_link = xs->sc_link;
762 	struct aic_tinfo *ti = &sc->sc_tinfo[sc_link->target];
763 	struct scsi_sense *ss = (void *)&acb->scsi_cmd;
764 
765 	AIC_MISC(("requesting sense  "));
766 	/* Next, setup a request sense command block */
767 	bzero(ss, sizeof(*ss));
768 	ss->opcode = REQUEST_SENSE;
769 	ss->byte2 = sc_link->lun << 5;
770 	ss->length = sizeof(struct scsi_sense_data);
771 	acb->scsi_cmd_length = sizeof(*ss);
772 	acb->data_addr = (char *)&xs->sense;
773 	acb->data_length = sizeof(struct scsi_sense_data);
774 	acb->flags |= ACB_SENSE;
775 	ti->senses++;
776 	if (acb->flags & ACB_NEXUS)
777 		ti->lubusy &= ~(1 << sc_link->lun);
778 	if (acb == sc->sc_nexus) {
779 		aic_select(sc, acb);
780 	} else {
781 		aic_dequeue(sc, acb);
782 		TAILQ_INSERT_HEAD(&sc->ready_list, acb, chain);
783 		if (sc->sc_state == AIC_IDLE)
784 			aic_sched(sc);
785 	}
786 }
787 
788 /*
789  * POST PROCESSING OF SCSI_CMD (usually current)
790  */
791 void
792 aic_done(struct aic_softc *sc, struct aic_acb *acb)
793 {
794 	struct scsi_xfer *xs = acb->xs;
795 	struct scsi_link *sc_link = xs->sc_link;
796 	struct aic_tinfo *ti = &sc->sc_tinfo[sc_link->target];
797 
798 	AIC_TRACE(("aic_done  "));
799 
800 	/*
801 	 * Now, if we've come here with no error code, i.e. we've kept the
802 	 * initial XS_NOERROR, and the status code signals that we should
803 	 * check sense, we'll need to set up a request sense cmd block and
804 	 * push the command back into the ready queue *before* any other
805 	 * commands for this target/lunit, else we lose the sense info.
806 	 * We don't support chk sense conditions for the request sense cmd.
807 	 */
808 	if (xs->error == XS_NOERROR) {
809 		if (acb->flags & ACB_ABORT) {
810 			xs->error = XS_DRIVER_STUFFUP;
811 		} else if (acb->flags & ACB_SENSE) {
812 			xs->error = XS_SENSE;
813 		} else if (acb->target_stat == SCSI_CHECK) {
814 			/* First, save the return values */
815 			xs->resid = acb->data_length;
816 			xs->status = acb->target_stat;
817 			aic_sense(sc, acb);
818 			return;
819 		} else {
820 			xs->resid = acb->data_length;
821 		}
822 	}
823 
824 #ifdef AIC_DEBUG
825 	if ((aic_debug & AIC_SHOWMISC) != 0) {
826 		if (xs->resid != 0)
827 			printf("resid=%lu ", (u_long)xs->resid);
828 		if (xs->error == XS_SENSE)
829 			printf("sense=0x%02x\n", xs->sense.error_code);
830 		else
831 			printf("error=%d\n", xs->error);
832 	}
833 #endif
834 
835 	/*
836 	 * Remove the ACB from whatever queue it happens to be on.
837 	 */
838 	if (acb->flags & ACB_NEXUS)
839 		ti->lubusy &= ~(1 << sc_link->lun);
840 	if (acb == sc->sc_nexus) {
841 		sc->sc_nexus = NULL;
842 		sc->sc_state = AIC_IDLE;
843 		aic_sched(sc);
844 	} else
845 		aic_dequeue(sc, acb);
846 
847 	ti->cmds++;
848 	scsi_done(xs);
849 }
850 
851 void
852 aic_dequeue(struct aic_softc *sc, struct aic_acb *acb)
853 {
854 
855 	if (acb->flags & ACB_NEXUS) {
856 		TAILQ_REMOVE(&sc->nexus_list, acb, chain);
857 	} else {
858 		TAILQ_REMOVE(&sc->ready_list, acb, chain);
859 	}
860 }
861 
862 /*
863  * INTERRUPT/PROTOCOL ENGINE
864  */
865 
866 /*
867  * Precondition:
868  * The SCSI bus is already in the MSGI phase and there is a message byte
869  * on the bus, along with an asserted REQ signal.
870  */
871 void
872 aic_msgin(struct aic_softc *sc)
873 {
874 	bus_space_tag_t iot = sc->sc_iot;
875 	bus_space_handle_t ioh = sc->sc_ioh;
876 	u_char sstat1;
877 	int n;
878 
879 	AIC_TRACE(("aic_msgin  "));
880 
881 	if (sc->sc_prevphase == PH_MSGIN) {
882 		/* This is a continuation of the previous message. */
883 		n = sc->sc_imp - sc->sc_imess;
884 		goto nextbyte;
885 	}
886 
887 	/* This is a new MESSAGE IN phase.  Clean up our state. */
888 	sc->sc_flags &= ~AIC_DROP_MSGIN;
889 
890 nextmsg:
891 	n = 0;
892 	sc->sc_imp = &sc->sc_imess[n];
893 
894 nextbyte:
895 	/*
896 	 * Read a whole message, but don't ack the last byte.  If we reject the
897 	 * message, we have to assert ATN during the message transfer phase
898 	 * itself.
899 	 */
900 	for (;;) {
901 		for (;;) {
902 			sstat1 = bus_space_read_1(iot, ioh, SSTAT1);
903 			if ((sstat1 & (REQINIT | PHASECHG | BUSFREE)) != 0)
904 				break;
905 			/* Wait for REQINIT.  XXX Need timeout. */
906 		}
907 		if ((sstat1 & (PHASECHG | BUSFREE)) != 0) {
908 			/*
909 			 * Target left MESSAGE IN, probably because it
910 			 * a) noticed our ATN signal, or
911 			 * b) ran out of messages.
912 			 */
913 			goto out;
914 		}
915 
916 		/* If parity error, just dump everything on the floor. */
917 		if ((sstat1 & SCSIPERR) != 0) {
918 			sc->sc_flags |= AIC_DROP_MSGIN;
919 			aic_sched_msgout(sc, SEND_PARITY_ERROR);
920 		}
921 
922 		/* Gather incoming message bytes if needed. */
923 		if ((sc->sc_flags & AIC_DROP_MSGIN) == 0) {
924 			if (n >= AIC_MAX_MSG_LEN) {
925 				(void) bus_space_read_1(iot, ioh, SCSIDAT);
926 				sc->sc_flags |= AIC_DROP_MSGIN;
927 				aic_sched_msgout(sc, SEND_REJECT);
928 			} else {
929 				*sc->sc_imp++ = bus_space_read_1(iot, ioh,
930 				    SCSIDAT);
931 				n++;
932 				/*
933 				 * This testing is suboptimal, but most
934 				 * messages will be of the one byte variety, so
935 				 * it should not affect performance
936 				 * significantly.
937 				 */
938 				if (n == 1 && IS1BYTEMSG(sc->sc_imess[0]))
939 					break;
940 				if (n == 2 && IS2BYTEMSG(sc->sc_imess[0]))
941 					break;
942 				if (n >= 3 && ISEXTMSG(sc->sc_imess[0]) &&
943 				    n == sc->sc_imess[1] + 2)
944 					break;
945 			}
946 		} else
947 			(void) bus_space_read_1(iot, ioh, SCSIDAT);
948 
949 		/*
950 		 * If we reach this spot we're either:
951 		 * a) in the middle of a multi-byte message, or
952 		 * b) dropping bytes.
953 		 */
954 		bus_space_write_1(iot, ioh, SXFRCTL0, CHEN | SPIOEN);
955 		/* Ack the last byte read. */
956 		(void) bus_space_read_1(iot, ioh, SCSIDAT);
957 		bus_space_write_1(iot, ioh, SXFRCTL0, CHEN);
958 		while ((bus_space_read_1(iot, ioh, SCSISIG) & ACKI) != 0)
959 			;
960 	}
961 
962 	AIC_MISC(("n=%d imess=0x%02x  ", n, sc->sc_imess[0]));
963 
964 	/* We now have a complete message.  Parse it. */
965 	switch (sc->sc_state) {
966 		struct aic_acb *acb;
967 		struct scsi_link *sc_link;
968 		struct aic_tinfo *ti;
969 
970 	case AIC_CONNECTED:
971 		AIC_ASSERT(sc->sc_nexus != NULL);
972 		acb = sc->sc_nexus;
973 		ti = &sc->sc_tinfo[acb->xs->sc_link->target];
974 
975 		switch (sc->sc_imess[0]) {
976 		case MSG_CMDCOMPLETE:
977 			if ((long)sc->sc_dleft < 0) {
978 				sc_link = acb->xs->sc_link;
979 				printf("%s: %lu extra bytes from %d:%d\n",
980 				    sc->sc_dev.dv_xname, (u_long)-sc->sc_dleft,
981 				    sc_link->target, sc_link->lun);
982 				acb->data_length = 0;
983 			}
984 			acb->xs->resid = acb->data_length = sc->sc_dleft;
985 			sc->sc_state = AIC_CMDCOMPLETE;
986 			break;
987 
988 		case MSG_PARITY_ERROR:
989 			/* Resend the last message. */
990 			aic_sched_msgout(sc, sc->sc_lastmsg);
991 			break;
992 
993 		case MSG_MESSAGE_REJECT:
994 			AIC_MISC(("message rejected %02x  ", sc->sc_lastmsg));
995 			switch (sc->sc_lastmsg) {
996 #if AIC_USE_SYNCHRONOUS + AIC_USE_WIDE
997 			case SEND_IDENTIFY:
998 				ti->flags &= ~(DO_SYNC | DO_WIDE);
999 				ti->period = ti->offset = 0;
1000 				aic_setsync(sc, ti);
1001 				ti->width = 0;
1002 				break;
1003 #endif
1004 #if AIC_USE_SYNCHRONOUS
1005 			case SEND_SDTR:
1006 				ti->flags &= ~DO_SYNC;
1007 				ti->period = ti->offset = 0;
1008 				aic_setsync(sc, ti);
1009 				break;
1010 #endif
1011 #if AIC_USE_WIDE
1012 			case SEND_WDTR:
1013 				ti->flags &= ~DO_WIDE;
1014 				ti->width = 0;
1015 				break;
1016 #endif
1017 			case SEND_INIT_DET_ERR:
1018 				aic_sched_msgout(sc, SEND_ABORT);
1019 				break;
1020 			}
1021 			break;
1022 
1023 		case MSG_NOOP:
1024 			break;
1025 
1026 		case MSG_DISCONNECT:
1027 			ti->dconns++;
1028 			sc->sc_state = AIC_DISCONNECT;
1029 			break;
1030 
1031 		case MSG_SAVEDATAPOINTER:
1032 			acb->data_addr = sc->sc_dp;
1033 			acb->data_length = sc->sc_dleft;
1034 			break;
1035 
1036 		case MSG_RESTOREPOINTERS:
1037 			sc->sc_dp = acb->data_addr;
1038 			sc->sc_dleft = acb->data_length;
1039 			sc->sc_cp = (u_char *)&acb->scsi_cmd;
1040 			sc->sc_cleft = acb->scsi_cmd_length;
1041 			break;
1042 
1043 		case MSG_EXTENDED:
1044 			switch (sc->sc_imess[2]) {
1045 #if AIC_USE_SYNCHRONOUS
1046 			case MSG_EXT_SDTR:
1047 				if (sc->sc_imess[1] != 3)
1048 					goto reject;
1049 				ti->period = sc->sc_imess[3];
1050 				ti->offset = sc->sc_imess[4];
1051 				ti->flags &= ~DO_SYNC;
1052 				if (ti->offset == 0) {
1053 				} else if (ti->period < sc->sc_minsync ||
1054 				    ti->period > sc->sc_maxsync ||
1055 				    ti->offset > 8) {
1056 					ti->period = ti->offset = 0;
1057 					aic_sched_msgout(sc, SEND_SDTR);
1058 				} else {
1059 					sc_print_addr(acb->xs->sc_link);
1060 					printf("sync, offset %d, ",
1061 					    ti->offset);
1062 					printf("period %dnsec\n",
1063 					    ti->period * 4);
1064 				}
1065 				aic_setsync(sc, ti);
1066 				break;
1067 #endif
1068 
1069 #if AIC_USE_WIDE
1070 			case MSG_EXT_WDTR:
1071 				if (sc->sc_imess[1] != 2)
1072 					goto reject;
1073 				ti->width = sc->sc_imess[3];
1074 				ti->flags &= ~DO_WIDE;
1075 				if (ti->width == 0) {
1076 				} else if (ti->width > AIC_MAX_WIDTH) {
1077 					ti->width = 0;
1078 					aic_sched_msgout(sc, SEND_WDTR);
1079 				} else {
1080 					sc_print_addr(acb->xs->sc_link);
1081 					printf("wide, width %d\n",
1082 					    1 << (3 + ti->width));
1083 				}
1084 				break;
1085 #endif
1086 
1087 			default:
1088 				printf("%s: unrecognized MESSAGE EXTENDED; ",
1089 				    sc->sc_dev.dv_xname);
1090 				printf("sending REJECT\n");
1091 				AIC_BREAK();
1092 				goto reject;
1093 			}
1094 			break;
1095 
1096 		default:
1097 			printf("%s: unrecognized MESSAGE; sending REJECT\n",
1098 			    sc->sc_dev.dv_xname);
1099 			AIC_BREAK();
1100 		reject:
1101 			aic_sched_msgout(sc, SEND_REJECT);
1102 			break;
1103 		}
1104 		break;
1105 
1106 	case AIC_RESELECTED:
1107 		if (!MSG_ISIDENTIFY(sc->sc_imess[0])) {
1108 			printf("%s: reselect without IDENTIFY; ",
1109 			    sc->sc_dev.dv_xname);
1110 			printf("sending DEVICE RESET\n");
1111 			AIC_BREAK();
1112 			goto reset;
1113 		}
1114 
1115 		(void) aic_reselect(sc, sc->sc_imess[0]);
1116 		break;
1117 
1118 	default:
1119 		printf("%s: unexpected MESSAGE IN; sending DEVICE RESET\n",
1120 		    sc->sc_dev.dv_xname);
1121 		AIC_BREAK();
1122 	reset:
1123 		aic_sched_msgout(sc, SEND_DEV_RESET);
1124 		break;
1125 
1126 #ifdef notdef
1127 	abort:
1128 		aic_sched_msgout(sc, SEND_ABORT);
1129 		break;
1130 #endif
1131 	}
1132 
1133 	bus_space_write_1(iot, ioh, SXFRCTL0, CHEN | SPIOEN);
1134 	/* Ack the last message byte. */
1135 	(void) bus_space_read_1(iot, ioh, SCSIDAT);
1136 	bus_space_write_1(iot, ioh, SXFRCTL0, CHEN);
1137 	while ((bus_space_read_1(iot, ioh, SCSISIG) & ACKI) != 0)
1138 		;
1139 
1140 	/* Go get the next message, if any. */
1141 	goto nextmsg;
1142 
1143 out:
1144 	AIC_MISC(("n=%d imess=0x%02x  ", n, sc->sc_imess[0]));
1145 }
1146 
1147 /*
1148  * Send the highest priority, scheduled message.
1149  */
1150 void
1151 aic_msgout(struct aic_softc *sc)
1152 {
1153 	bus_space_tag_t iot = sc->sc_iot;
1154 	bus_space_handle_t ioh = sc->sc_ioh;
1155 #if AIC_USE_SYNCHRONOUS
1156 	struct aic_tinfo *ti;
1157 #endif
1158 	u_char sstat1;
1159 	int n;
1160 
1161 	AIC_TRACE(("aic_msgout  "));
1162 
1163 	/* Reset the FIFO. */
1164 	bus_space_write_1(iot, ioh, DMACNTRL0, RSTFIFO);
1165 	/* Enable REQ/ACK protocol. */
1166 	bus_space_write_1(iot, ioh, SXFRCTL0, CHEN | SPIOEN);
1167 
1168 	if (sc->sc_prevphase == PH_MSGOUT) {
1169 		if (sc->sc_omp == sc->sc_omess) {
1170 			/*
1171 			 * This is a retransmission.
1172 			 *
1173 			 * We get here if the target stayed in MESSAGE OUT
1174 			 * phase.  Section 5.1.9.2 of the SCSI 2 spec indicates
1175 			 * that all of the previously transmitted messages must
1176 			 * be sent again, in the same order.  Therefore, we
1177 			 * requeue all the previously transmitted messages, and
1178 			 * start again from the top.  Our simple priority
1179 			 * scheme keeps the messages in the right order.
1180 			 */
1181 			AIC_MISC(("retransmitting  "));
1182 			sc->sc_msgpriq |= sc->sc_msgoutq;
1183 			/*
1184 			 * Set ATN.  If we're just sending a trivial 1-byte
1185 			 * message, we'll clear ATN later on anyway.
1186 			 */
1187 			bus_space_write_1(iot, ioh, SCSISIG, PH_MSGOUT | ATNO);
1188 		} else {
1189 			/* This is a continuation of the previous message. */
1190 			n = sc->sc_omp - sc->sc_omess;
1191 			goto nextbyte;
1192 		}
1193 	}
1194 
1195 	/* No messages transmitted so far. */
1196 	sc->sc_msgoutq = 0;
1197 	sc->sc_lastmsg = 0;
1198 
1199 nextmsg:
1200 	/* Pick up highest priority message. */
1201 	sc->sc_currmsg = sc->sc_msgpriq & -sc->sc_msgpriq;
1202 	sc->sc_msgpriq &= ~sc->sc_currmsg;
1203 	sc->sc_msgoutq |= sc->sc_currmsg;
1204 
1205 	/* Build the outgoing message data. */
1206 	switch (sc->sc_currmsg) {
1207 	case SEND_IDENTIFY:
1208 		AIC_ASSERT(sc->sc_nexus != NULL);
1209 		sc->sc_omess[0] =
1210 		    MSG_IDENTIFY(sc->sc_nexus->xs->sc_link->lun, 1);
1211 		n = 1;
1212 		break;
1213 
1214 #if AIC_USE_SYNCHRONOUS
1215 	case SEND_SDTR:
1216 		AIC_ASSERT(sc->sc_nexus != NULL);
1217 		ti = &sc->sc_tinfo[sc->sc_nexus->xs->sc_link->target];
1218 		sc->sc_omess[4] = MSG_EXTENDED;
1219 		sc->sc_omess[3] = 3;
1220 		sc->sc_omess[2] = MSG_EXT_SDTR;
1221 		sc->sc_omess[1] = ti->period >> 2;
1222 		sc->sc_omess[0] = ti->offset;
1223 		n = 5;
1224 		break;
1225 #endif
1226 
1227 #if AIC_USE_WIDE
1228 	case SEND_WDTR:
1229 		AIC_ASSERT(sc->sc_nexus != NULL);
1230 		ti = &sc->sc_tinfo[sc->sc_nexus->xs->sc_link->target];
1231 		sc->sc_omess[3] = MSG_EXTENDED;
1232 		sc->sc_omess[2] = 2;
1233 		sc->sc_omess[1] = MSG_EXT_WDTR;
1234 		sc->sc_omess[0] = ti->width;
1235 		n = 4;
1236 		break;
1237 #endif
1238 
1239 	case SEND_DEV_RESET:
1240 		sc->sc_flags |= AIC_ABORTING;
1241 		sc->sc_omess[0] = MSG_BUS_DEV_RESET;
1242 		n = 1;
1243 		break;
1244 
1245 	case SEND_REJECT:
1246 		sc->sc_omess[0] = MSG_MESSAGE_REJECT;
1247 		n = 1;
1248 		break;
1249 
1250 	case SEND_PARITY_ERROR:
1251 		sc->sc_omess[0] = MSG_PARITY_ERROR;
1252 		n = 1;
1253 		break;
1254 
1255 	case SEND_INIT_DET_ERR:
1256 		sc->sc_omess[0] = MSG_INITIATOR_DET_ERR;
1257 		n = 1;
1258 		break;
1259 
1260 	case SEND_ABORT:
1261 		sc->sc_flags |= AIC_ABORTING;
1262 		sc->sc_omess[0] = MSG_ABORT;
1263 		n = 1;
1264 		break;
1265 
1266 	default:
1267 		printf("%s: unexpected MESSAGE OUT; sending NOOP\n",
1268 		    sc->sc_dev.dv_xname);
1269 		AIC_BREAK();
1270 		sc->sc_omess[0] = MSG_NOOP;
1271 		n = 1;
1272 		break;
1273 	}
1274 	sc->sc_omp = &sc->sc_omess[n];
1275 
1276 nextbyte:
1277 	/* Send message bytes. */
1278 	for (;;) {
1279 		for (;;) {
1280 			sstat1 = bus_space_read_1(iot, ioh, SSTAT1);
1281 			if ((sstat1 & (REQINIT | PHASECHG | BUSFREE)) != 0)
1282 				break;
1283 			/* Wait for REQINIT.  XXX Need timeout. */
1284 		}
1285 		if ((sstat1 & (PHASECHG | BUSFREE)) != 0) {
1286 			/*
1287 			 * Target left MESSAGE OUT, possibly to reject
1288 			 * our message.
1289 			 *
1290 			 * If this is the last message being sent, then we
1291 			 * deassert ATN, since either the target is going to
1292 			 * ignore this message, or it's going to ask for a
1293 			 * retransmission via MESSAGE PARITY ERROR (in which
1294 			 * case we reassert ATN anyway).
1295 			 */
1296 			if (sc->sc_msgpriq == 0)
1297 				bus_space_write_1(iot, ioh, CLRSINT1, CLRATNO);
1298 			goto out;
1299 		}
1300 
1301 		/* Clear ATN before last byte if this is the last message. */
1302 		if (n == 1 && sc->sc_msgpriq == 0)
1303 			bus_space_write_1(iot, ioh, CLRSINT1, CLRATNO);
1304 		/* Send message byte. */
1305 		bus_space_write_1(iot, ioh, SCSIDAT, *--sc->sc_omp);
1306 		--n;
1307 		/* Keep track of the last message we've sent any bytes of. */
1308 		sc->sc_lastmsg = sc->sc_currmsg;
1309 		/* Wait for ACK to be negated.  XXX Need timeout. */
1310 		while ((bus_space_read_1(iot, ioh, SCSISIG) & ACKI) != 0)
1311 			;
1312 
1313 		if (n == 0)
1314 			break;
1315 	}
1316 
1317 	/* We get here only if the entire message has been transmitted. */
1318 	if (sc->sc_msgpriq != 0) {
1319 		/* There are more outgoing messages. */
1320 		goto nextmsg;
1321 	}
1322 
1323 	/*
1324 	 * The last message has been transmitted.  We need to remember the last
1325 	 * message transmitted (in case the target switches to MESSAGE IN phase
1326 	 * and sends a MESSAGE REJECT), and the list of messages transmitted
1327 	 * this time around (in case the target stays in MESSAGE OUT phase to
1328 	 * request a retransmit).
1329 	 */
1330 
1331 out:
1332 	/* Disable REQ/ACK protocol. */
1333 	bus_space_write_1(iot, ioh, SXFRCTL0, CHEN);
1334 }
1335 
1336 /* aic_dataout_pio: perform a data transfer using the FIFO datapath in the aic6360
1337  * Precondition: The SCSI bus should be in the DOUT phase, with REQ asserted
1338  * and ACK deasserted (i.e. waiting for a data byte).
1339  * This new revision has been optimized (I tried) to make the common case fast,
1340  * and the rarer cases (as a result) somewhat more complex.
1341  */
1342 int
1343 aic_dataout_pio(struct aic_softc *sc, u_char *p, int n)
1344 {
1345 	bus_space_tag_t iot = sc->sc_iot;
1346 	bus_space_handle_t ioh = sc->sc_ioh;
1347 	u_char dmastat = 0;
1348 	int out = 0;
1349 #define DOUTAMOUNT 128		/* Full FIFO */
1350 
1351 	AIC_MISC(("%02x%02x  ", bus_space_read_1(iot, ioh, FIFOSTAT),
1352 	    bus_space_read_1(iot, ioh, SSTAT2)));
1353 
1354 	/* Clear host FIFO and counter. */
1355 	bus_space_write_1(iot, ioh, DMACNTRL0, RSTFIFO | WRITE);
1356 	/* Enable FIFOs. */
1357 	bus_space_write_1(iot, ioh, DMACNTRL0, ENDMA | DWORDPIO | WRITE);
1358 	bus_space_write_1(iot, ioh, SXFRCTL0, SCSIEN | DMAEN | CHEN);
1359 
1360 	/* Turn off ENREQINIT for now. */
1361 	bus_space_write_1(iot, ioh, SIMODE1,
1362 	    ENSCSIRST | ENSCSIPERR | ENBUSFREE | ENPHASECHG);
1363 
1364 	/* I have tried to make the main loop as tight as possible.  This
1365 	 * means that some of the code following the loop is a bit more
1366 	 * complex than otherwise.
1367 	 */
1368 	while (n > 0) {
1369 		for (;;) {
1370 			dmastat = bus_space_read_1(iot, ioh, DMASTAT);
1371 			if ((dmastat & (DFIFOEMP | INTSTAT)) != 0)
1372 				break;
1373 		}
1374 
1375 		if ((dmastat & INTSTAT) != 0)
1376 			goto phasechange;
1377 
1378 		if (n >= DOUTAMOUNT) {
1379 			n -= DOUTAMOUNT;
1380 			out += DOUTAMOUNT;
1381 
1382 #if AIC_USE_DWORDS
1383 			bus_space_write_multi_4(iot, ioh, DMADATALONG,
1384 			    (u_int32_t *)p, DOUTAMOUNT >> 2);
1385 #else
1386 			bus_space_write_multi_2(iot, ioh, DMADATA,
1387 			    (u_int16_t *)p, DOUTAMOUNT >> 1);
1388 #endif
1389 
1390 			p += DOUTAMOUNT;
1391 		} else {
1392 			int xfer;
1393 
1394 			xfer = n;
1395 			AIC_MISC(("%d> ", xfer));
1396 
1397 			n -= xfer;
1398 			out += xfer;
1399 
1400 #if AIC_USE_DWORDS
1401 			if (xfer >= 12) {
1402 				bus_space_write_multi_4(iot, ioh, DMADATALONG,
1403 				    (u_int32_t *)p, xfer >> 2);
1404 				p += xfer & ~3;
1405 				xfer &= 3;
1406 			}
1407 #else
1408 			if (xfer >= 8) {
1409 				bus_space_write_multi_2(iot, ioh,  DMADATA,
1410 				    (u_int16_t *)p, xfer >> 1);
1411 				p += xfer & ~1;
1412 				xfer &= 1;
1413 			}
1414 #endif
1415 
1416 			if (xfer > 0) {
1417 				bus_space_write_1(iot, ioh, DMACNTRL0,
1418 				    ENDMA | B8MODE | WRITE);
1419 				bus_space_write_multi_1(iot, ioh,  DMADATA, p,
1420 				    xfer);
1421 				p += xfer;
1422 				bus_space_write_1(iot, ioh, DMACNTRL0,
1423 				    ENDMA | DWORDPIO | WRITE);
1424 			}
1425 		}
1426 	}
1427 
1428 	if (out == 0) {
1429 		bus_space_write_1(iot, ioh, SXFRCTL1, BITBUCKET);
1430 		for (;;) {
1431 			if ((bus_space_read_1(iot, ioh, DMASTAT) & INTSTAT) !=
1432 			    0)
1433 				break;
1434 		}
1435 		bus_space_write_1(iot, ioh, SXFRCTL1, 0);
1436 		AIC_MISC(("extra data  "));
1437 	} else {
1438 		/* See the bytes off chip */
1439 		for (;;) {
1440 			dmastat = bus_space_read_1(iot, ioh, DMASTAT);
1441 			if ((dmastat & INTSTAT) != 0)
1442 				goto phasechange;
1443 			if ((dmastat & DFIFOEMP) != 0 &&
1444 			    (bus_space_read_1(iot, ioh, SSTAT2) & SEMPTY) != 0)
1445 				break;
1446 		}
1447 	}
1448 
1449 phasechange:
1450 	if ((dmastat & INTSTAT) != 0) {
1451 		/* Some sort of phase change. */
1452 		int amount;
1453 
1454 		/* Stop transfers, do some accounting */
1455 		amount = bus_space_read_1(iot, ioh, FIFOSTAT) +
1456 		    (bus_space_read_1(iot, ioh, SSTAT2) & 15);
1457 		if (amount > 0) {
1458 			out -= amount;
1459 			bus_space_write_1(iot, ioh, DMACNTRL0,
1460 			    RSTFIFO | WRITE);
1461 			bus_space_write_1(iot, ioh, SXFRCTL0, CHEN | CLRCH);
1462 			AIC_MISC(("+%d ", amount));
1463 		}
1464 	}
1465 
1466 	/* Turn on ENREQINIT again. */
1467 	bus_space_write_1(iot, ioh, SIMODE1,
1468 	    ENSCSIRST | ENSCSIPERR | ENBUSFREE | ENREQINIT | ENPHASECHG);
1469 
1470 	/* Stop the FIFO data path. */
1471 	bus_space_write_1(iot, ioh, SXFRCTL0, CHEN);
1472 	bus_space_write_1(iot, ioh, DMACNTRL0, 0);
1473 
1474 	return out;
1475 }
1476 
1477 /* aic_datain_pio: perform data transfers using the FIFO datapath in the aic6360
1478  * Precondition: The SCSI bus should be in the DIN phase, with REQ asserted
1479  * and ACK deasserted (i.e. at least one byte is ready).
1480  * For now, uses a pretty dumb algorithm, hangs around until all data has been
1481  * transferred.  This, is OK for fast targets, but not so smart for slow
1482  * targets which don't disconnect or for huge transfers.
1483  */
1484 int
1485 aic_datain_pio(struct aic_softc *sc, u_char *p, int n)
1486 {
1487 	bus_space_tag_t iot = sc->sc_iot;
1488 	bus_space_handle_t ioh = sc->sc_ioh;
1489 	u_char dmastat;
1490 	int in = 0;
1491 #define DINAMOUNT 128		/* Full FIFO */
1492 
1493 	AIC_MISC(("%02x%02x  ", bus_space_read_1(iot, ioh, FIFOSTAT),
1494 	    bus_space_read_1(iot, ioh, SSTAT2)));
1495 
1496 	/* Clear host FIFO and counter. */
1497 	bus_space_write_1(iot, ioh, DMACNTRL0, RSTFIFO);
1498 	/* Enable FIFOs. */
1499 	bus_space_write_1(iot, ioh, DMACNTRL0, ENDMA | DWORDPIO);
1500 	bus_space_write_1(iot, ioh, SXFRCTL0, SCSIEN | DMAEN | CHEN);
1501 
1502 	/* Turn off ENREQINIT for now. */
1503 	bus_space_write_1(iot, ioh, SIMODE1,
1504 	    ENSCSIRST | ENSCSIPERR | ENBUSFREE | ENPHASECHG);
1505 
1506 	/* We leave this loop if one or more of the following is true:
1507 	 * a) phase != PH_DATAIN && FIFOs are empty
1508 	 * b) SCSIRSTI is set (a reset has occurred) or busfree is detected.
1509 	 */
1510 	while (n > 0) {
1511 		/* Wait for fifo half full or phase mismatch */
1512 		for (;;) {
1513 			dmastat = bus_space_read_1(iot, ioh, DMASTAT);
1514 			if ((dmastat & (DFIFOFULL | INTSTAT)) != 0)
1515 				break;
1516 		}
1517 
1518 		if ((dmastat & DFIFOFULL) != 0) {
1519 			n -= DINAMOUNT;
1520 			in += DINAMOUNT;
1521 
1522 #if AIC_USE_DWORDS
1523 			bus_space_read_multi_4(iot, ioh, DMADATALONG,
1524 			    (u_int32_t *)p, DINAMOUNT >> 2);
1525 #else
1526 			bus_space_read_multi_2(iot, ioh, DMADATA,
1527 			    (u_int16_t *)p, DINAMOUNT >> 1);
1528 #endif
1529 
1530 			p += DINAMOUNT;
1531 		} else {
1532 			int xfer;
1533 
1534 			xfer = min(bus_space_read_1(iot, ioh, FIFOSTAT), n);
1535 			AIC_MISC((">%d ", xfer));
1536 
1537 			n -= xfer;
1538 			in += xfer;
1539 
1540 #if AIC_USE_DWORDS
1541 			if (xfer >= 12) {
1542 				bus_space_read_multi_4(iot, ioh, DMADATALONG,
1543 				    (u_int32_t *)p, xfer >> 2);
1544 				p += xfer & ~3;
1545 				xfer &= 3;
1546 			}
1547 #else
1548 			if (xfer >= 8) {
1549 				bus_space_read_multi_2(iot, ioh, DMADATA,
1550 				    (u_int16_t *)p, xfer >> 1);
1551 				p += xfer & ~1;
1552 				xfer &= 1;
1553 			}
1554 #endif
1555 
1556 			if (xfer > 0) {
1557 				bus_space_write_1(iot, ioh, DMACNTRL0,
1558 				    ENDMA | B8MODE);
1559 				bus_space_read_multi_1(iot, ioh, DMADATA, p,
1560 				    xfer);
1561 				p += xfer;
1562 				bus_space_write_1(iot, ioh, DMACNTRL0,
1563 				    ENDMA | DWORDPIO);
1564 			}
1565 		}
1566 
1567 		if ((dmastat & INTSTAT) != 0)
1568 			goto phasechange;
1569 	}
1570 
1571 	/* Some SCSI-devices are rude enough to transfer more data than what
1572 	 * was requested, e.g. 2048 bytes from a CD-ROM instead of the
1573 	 * requested 512.  Test for progress, i.e. real transfers.  If no real
1574 	 * transfers have been performed (n is probably already zero) and the
1575 	 * FIFO is not empty, waste some bytes....
1576 	 */
1577 	if (in == 0) {
1578 		bus_space_write_1(iot, ioh, SXFRCTL1, BITBUCKET);
1579 		for (;;) {
1580 			if ((bus_space_read_1(iot, ioh, DMASTAT) & INTSTAT) !=
1581 			    0)
1582 				break;
1583 		}
1584 		bus_space_write_1(iot, ioh, SXFRCTL1, 0);
1585 		AIC_MISC(("extra data  "));
1586 	}
1587 
1588 phasechange:
1589 	/* Turn on ENREQINIT again. */
1590 	bus_space_write_1(iot, ioh, SIMODE1,
1591 	    ENSCSIRST | ENSCSIPERR | ENBUSFREE | ENREQINIT | ENPHASECHG);
1592 
1593 	/* Stop the FIFO data path. */
1594 	bus_space_write_1(iot, ioh, SXFRCTL0, CHEN);
1595 	bus_space_write_1(iot, ioh, DMACNTRL0, 0);
1596 
1597 	return in;
1598 }
1599 
1600 /*
1601  * This is the workhorse routine of the driver.
1602  * Deficiencies (for now):
1603  * 1) always uses programmed I/O
1604  */
1605 int
1606 aicintr(void *arg)
1607 {
1608 	struct aic_softc *sc = arg;
1609 	bus_space_tag_t iot = sc->sc_iot;
1610 	bus_space_handle_t ioh = sc->sc_ioh;
1611 	u_char sstat0, sstat1;
1612 	struct aic_acb *acb;
1613 	struct scsi_link *sc_link;
1614 	struct aic_tinfo *ti;
1615 	int n;
1616 
1617 	/*
1618 	 * Clear INTEN.  We enable it again before returning.  This makes the
1619 	 * interrupt esssentially level-triggered.
1620 	 */
1621 	bus_space_write_1(iot, ioh, DMACNTRL0, 0);
1622 
1623 	AIC_TRACE(("aicintr  "));
1624 
1625 loop:
1626 	/*
1627 	 * First check for abnormal conditions, such as reset.
1628 	 */
1629 	sstat1 = bus_space_read_1(iot, ioh, SSTAT1);
1630 	AIC_MISC(("sstat1:0x%02x ", sstat1));
1631 
1632 	if ((sstat1 & SCSIRSTI) != 0) {
1633 		printf("%s: SCSI bus reset\n", sc->sc_dev.dv_xname);
1634 		goto reset;
1635 	}
1636 
1637 	/*
1638 	 * Check for less serious errors.
1639 	 */
1640 	if ((sstat1 & SCSIPERR) != 0) {
1641 		printf("%s: SCSI bus parity error\n", sc->sc_dev.dv_xname);
1642 		bus_space_write_1(iot, ioh, CLRSINT1, CLRSCSIPERR);
1643 		if (sc->sc_prevphase == PH_MSGIN) {
1644 			sc->sc_flags |= AIC_DROP_MSGIN;
1645 			aic_sched_msgout(sc, SEND_PARITY_ERROR);
1646 		} else
1647 			aic_sched_msgout(sc, SEND_INIT_DET_ERR);
1648 	}
1649 
1650 	/*
1651 	 * If we're not already busy doing something test for the following
1652 	 * conditions:
1653 	 * 1) We have been reselected by something
1654 	 * 2) We have selected something successfully
1655 	 * 3) Our selection process has timed out
1656 	 * 4) This is really a bus free interrupt just to get a new command
1657 	 *    going?
1658 	 * 5) Spurious interrupt?
1659 	 */
1660 	switch (sc->sc_state) {
1661 	case AIC_IDLE:
1662 	case AIC_SELECTING:
1663 		sstat0 = bus_space_read_1(iot, ioh, SSTAT0);
1664 		AIC_MISC(("sstat0:0x%02x ", sstat0));
1665 
1666 		if ((sstat0 & TARGET) != 0) {
1667 			/*
1668 			 * We don't currently support target mode.
1669 			 */
1670 			printf("%s: target mode selected; going to BUS FREE\n",
1671 			    sc->sc_dev.dv_xname);
1672 			bus_space_write_1(iot, ioh, SCSISIG, 0);
1673 
1674 			goto sched;
1675 		} else if ((sstat0 & SELDI) != 0) {
1676 			AIC_MISC(("reselected  "));
1677 
1678 			/*
1679 			 * If we're trying to select a target ourselves,
1680 			 * push our command back into the ready list.
1681 			 */
1682 			if (sc->sc_state == AIC_SELECTING) {
1683 				AIC_MISC(("backoff selector  "));
1684 				AIC_ASSERT(sc->sc_nexus != NULL);
1685 				acb = sc->sc_nexus;
1686 				sc->sc_nexus = NULL;
1687 				TAILQ_INSERT_HEAD(&sc->ready_list, acb, chain);
1688 			}
1689 
1690 			/* Save reselection ID. */
1691 			sc->sc_selid = bus_space_read_1(iot, ioh, SELID);
1692 
1693 			sc->sc_state = AIC_RESELECTED;
1694 		} else if ((sstat0 & SELDO) != 0) {
1695 			AIC_MISC(("selected  "));
1696 
1697 			/* We have selected a target. Things to do:
1698 			 * a) Determine what message(s) to send.
1699 			 * b) Verify that we're still selecting the target.
1700 			 * c) Mark device as busy.
1701 			 */
1702 			if (sc->sc_state != AIC_SELECTING) {
1703 				printf("%s: selection out while idle; ",
1704 				    sc->sc_dev.dv_xname);
1705 				printf("resetting\n");
1706 				AIC_BREAK();
1707 				goto reset;
1708 			}
1709 			AIC_ASSERT(sc->sc_nexus != NULL);
1710 			acb = sc->sc_nexus;
1711 			sc_link = acb->xs->sc_link;
1712 			ti = &sc->sc_tinfo[sc_link->target];
1713 
1714 			sc->sc_msgpriq = SEND_IDENTIFY;
1715 			if (acb->flags & ACB_RESET)
1716 				sc->sc_msgpriq |= SEND_DEV_RESET;
1717 			else if (acb->flags & ACB_ABORT)
1718 				sc->sc_msgpriq |= SEND_ABORT;
1719 			else {
1720 #if AIC_USE_SYNCHRONOUS
1721 				if ((ti->flags & DO_SYNC) != 0)
1722 					sc->sc_msgpriq |= SEND_SDTR;
1723 #endif
1724 #if AIC_USE_WIDE
1725 				if ((ti->flags & DO_WIDE) != 0)
1726 					sc->sc_msgpriq |= SEND_WDTR;
1727 #endif
1728 			}
1729 
1730 			acb->flags |= ACB_NEXUS;
1731 			ti->lubusy |= (1 << sc_link->lun);
1732 
1733 			/* Do an implicit RESTORE POINTERS. */
1734 			sc->sc_dp = acb->data_addr;
1735 			sc->sc_dleft = acb->data_length;
1736 			sc->sc_cp = (u_char *)&acb->scsi_cmd;
1737 			sc->sc_cleft = acb->scsi_cmd_length;
1738 
1739 			/* On our first connection, schedule a timeout. */
1740 			if ((acb->xs->flags & SCSI_POLL) == 0)
1741 				timeout_add_msec(&acb->xs->stimeout, acb->timeout);
1742 
1743 			sc->sc_state = AIC_CONNECTED;
1744 		} else if ((sstat1 & SELTO) != 0) {
1745 			AIC_MISC(("selection timeout  "));
1746 
1747 			if (sc->sc_state != AIC_SELECTING) {
1748 				printf("%s: selection timeout while idle; ",
1749 				    sc->sc_dev.dv_xname);
1750 				printf("resetting\n");
1751 				AIC_BREAK();
1752 				goto reset;
1753 			}
1754 			AIC_ASSERT(sc->sc_nexus != NULL);
1755 			acb = sc->sc_nexus;
1756 
1757 			bus_space_write_1(iot, ioh, SXFRCTL1, 0);
1758 			bus_space_write_1(iot, ioh, SCSISEQ, ENRESELI);
1759 			bus_space_write_1(iot, ioh, CLRSINT1, CLRSELTIMO);
1760 			delay(250);
1761 
1762 			acb->xs->error = XS_SELTIMEOUT;
1763 			goto finish;
1764 		} else {
1765 			if (sc->sc_state != AIC_IDLE) {
1766 				printf("%s: BUS FREE while not idle; ",
1767 				    sc->sc_dev.dv_xname);
1768 				printf("state=%d\n", sc->sc_state);
1769 				AIC_BREAK();
1770 				goto out;
1771 			}
1772 
1773 			goto sched;
1774 		}
1775 
1776 		/*
1777 		 * Turn off selection stuff, and prepare to catch bus free
1778 		 * interrupts, parity errors, and phase changes.
1779 		 */
1780 		bus_space_write_1(iot, ioh, SXFRCTL0, CHEN | CLRSTCNT | CLRCH);
1781 		bus_space_write_1(iot, ioh, SXFRCTL1, 0);
1782 		bus_space_write_1(iot, ioh, SCSISEQ, ENAUTOATNP);
1783 		bus_space_write_1(iot, ioh, CLRSINT0, CLRSELDI | CLRSELDO);
1784 		bus_space_write_1(iot, ioh, CLRSINT1,
1785 		    CLRBUSFREE | CLRPHASECHG);
1786 		bus_space_write_1(iot, ioh, SIMODE0, 0);
1787 		bus_space_write_1(iot, ioh, SIMODE1,
1788 		    ENSCSIRST | ENSCSIPERR | ENBUSFREE | ENREQINIT |
1789 		    ENPHASECHG);
1790 
1791 		sc->sc_flags = 0;
1792 		sc->sc_prevphase = PH_INVALID;
1793 		goto dophase;
1794 	}
1795 
1796 	if ((sstat1 & BUSFREE) != 0) {
1797 		/* We've gone to BUS FREE phase. */
1798 		bus_space_write_1(iot, ioh, CLRSINT1,
1799 		    CLRBUSFREE | CLRPHASECHG);
1800 
1801 		switch (sc->sc_state) {
1802 		case AIC_RESELECTED:
1803 			goto sched;
1804 
1805 		case AIC_CONNECTED:
1806 			AIC_ASSERT(sc->sc_nexus != NULL);
1807 			acb = sc->sc_nexus;
1808 
1809 #if AIC_USE_SYNCHRONOUS + AIC_USE_WIDE
1810 			if (sc->sc_prevphase == PH_MSGOUT) {
1811 				/*
1812 				 * If the target went to BUS FREE phase during
1813 				 * or immediately after sending a SDTR or WDTR
1814 				 * message, disable negotiation.
1815 				 */
1816 				sc_link = acb->xs->sc_link;
1817 				ti = &sc->sc_tinfo[sc_link->target];
1818 				switch (sc->sc_lastmsg) {
1819 #if AIC_USE_SYNCHRONOUS
1820 				case SEND_SDTR:
1821 					ti->flags &= ~DO_SYNC;
1822 					ti->period = ti->offset = 0;
1823 					break;
1824 #endif
1825 #if AIC_USE_WIDE
1826 				case SEND_WDTR:
1827 					ti->flags &= ~DO_WIDE;
1828 					ti->width = 0;
1829 					break;
1830 #endif
1831 				}
1832 			}
1833 #endif
1834 
1835 			if ((sc->sc_flags & AIC_ABORTING) == 0) {
1836 				/*
1837 				 * Section 5.1.1 of the SCSI 2 spec suggests
1838 				 * issuing a REQUEST SENSE following an
1839 				 * unexpected disconnect.  Some devices go into
1840 				 * a contingent allegiance condition when
1841 				 * disconnecting, and this is necessary to
1842 				 * clean up their state.
1843 				 */
1844 				printf("%s: unexpected disconnect; ",
1845 				    sc->sc_dev.dv_xname);
1846 				printf("sending REQUEST SENSE\n");
1847 				AIC_BREAK();
1848 				aic_sense(sc, acb);
1849 				goto out;
1850 			}
1851 
1852 			acb->xs->error = XS_DRIVER_STUFFUP;
1853 			goto finish;
1854 
1855 		case AIC_DISCONNECT:
1856 			AIC_ASSERT(sc->sc_nexus != NULL);
1857 			acb = sc->sc_nexus;
1858 #if 1 /* XXXX */
1859 			acb->data_addr = sc->sc_dp;
1860 			acb->data_length = sc->sc_dleft;
1861 #endif
1862 			TAILQ_INSERT_HEAD(&sc->nexus_list, acb, chain);
1863 			sc->sc_nexus = NULL;
1864 			goto sched;
1865 
1866 		case AIC_CMDCOMPLETE:
1867 			AIC_ASSERT(sc->sc_nexus != NULL);
1868 			acb = sc->sc_nexus;
1869 			goto finish;
1870 		}
1871 	}
1872 
1873 	bus_space_write_1(iot, ioh, CLRSINT1, CLRPHASECHG);
1874 
1875 dophase:
1876 	if ((sstat1 & REQINIT) == 0) {
1877 		/* Wait for REQINIT. */
1878 		goto out;
1879 	}
1880 
1881 	sc->sc_phase = bus_space_read_1(iot, ioh, SCSISIG) & PH_MASK;
1882 	bus_space_write_1(iot, ioh, SCSISIG, sc->sc_phase);
1883 
1884 	switch (sc->sc_phase) {
1885 	case PH_MSGOUT:
1886 		if (sc->sc_state != AIC_CONNECTED &&
1887 		    sc->sc_state != AIC_RESELECTED)
1888 			break;
1889 		aic_msgout(sc);
1890 		sc->sc_prevphase = PH_MSGOUT;
1891 		goto loop;
1892 
1893 	case PH_MSGIN:
1894 		if (sc->sc_state != AIC_CONNECTED &&
1895 		    sc->sc_state != AIC_RESELECTED)
1896 			break;
1897 		aic_msgin(sc);
1898 		sc->sc_prevphase = PH_MSGIN;
1899 		goto loop;
1900 
1901 	case PH_CMD:
1902 		if (sc->sc_state != AIC_CONNECTED)
1903 			break;
1904 #ifdef AIC_DEBUG
1905 		if ((aic_debug & AIC_SHOWMISC) != 0) {
1906 			AIC_ASSERT(sc->sc_nexus != NULL);
1907 			acb = sc->sc_nexus;
1908 			printf("cmd=0x%02x+%d ",
1909 			    acb->scsi_cmd.opcode, acb->scsi_cmd_length-1);
1910 		}
1911 #endif
1912 		n = aic_dataout_pio(sc, sc->sc_cp, sc->sc_cleft);
1913 		sc->sc_cp += n;
1914 		sc->sc_cleft -= n;
1915 		sc->sc_prevphase = PH_CMD;
1916 		goto loop;
1917 
1918 	case PH_DATAOUT:
1919 		if (sc->sc_state != AIC_CONNECTED)
1920 			break;
1921 		AIC_MISC(("dataout dleft=%lu ", (u_long)sc->sc_dleft));
1922 		n = aic_dataout_pio(sc, sc->sc_dp, sc->sc_dleft);
1923 		sc->sc_dp += n;
1924 		sc->sc_dleft -= n;
1925 		sc->sc_prevphase = PH_DATAOUT;
1926 		goto loop;
1927 
1928 	case PH_DATAIN:
1929 		if (sc->sc_state != AIC_CONNECTED)
1930 			break;
1931 		AIC_MISC(("datain %lu ", (u_long)sc->sc_dleft));
1932 		n = aic_datain_pio(sc, sc->sc_dp, sc->sc_dleft);
1933 		sc->sc_dp += n;
1934 		sc->sc_dleft -= n;
1935 		sc->sc_prevphase = PH_DATAIN;
1936 		goto loop;
1937 
1938 	case PH_STAT:
1939 		if (sc->sc_state != AIC_CONNECTED)
1940 			break;
1941 		AIC_ASSERT(sc->sc_nexus != NULL);
1942 		acb = sc->sc_nexus;
1943 		bus_space_write_1(iot, ioh, SXFRCTL0, CHEN | SPIOEN);
1944 		acb->target_stat = bus_space_read_1(iot, ioh, SCSIDAT);
1945 		bus_space_write_1(iot, ioh, SXFRCTL0, CHEN);
1946 		AIC_MISC(("target_stat=0x%02x ", acb->target_stat));
1947 		sc->sc_prevphase = PH_STAT;
1948 		goto loop;
1949 	}
1950 
1951 	printf("%s: unexpected bus phase; resetting\n", sc->sc_dev.dv_xname);
1952 	AIC_BREAK();
1953 reset:
1954 	aic_init(sc);
1955 	return 1;
1956 
1957 finish:
1958 	timeout_del(&acb->xs->stimeout);
1959 	aic_done(sc, acb);
1960 	goto out;
1961 
1962 sched:
1963 	sc->sc_state = AIC_IDLE;
1964 	aic_sched(sc);
1965 	goto out;
1966 
1967 out:
1968 	bus_space_write_1(iot, ioh, DMACNTRL0, INTEN);
1969 	return 1;
1970 }
1971 
1972 void
1973 aic_abort(struct aic_softc *sc, struct aic_acb *acb)
1974 {
1975 
1976 	/* 2 secs for the abort */
1977 	acb->timeout = AIC_ABORT_TIMEOUT;
1978 	acb->flags |= ACB_ABORT;
1979 
1980 	if (acb == sc->sc_nexus) {
1981 		/*
1982 		 * If we're still selecting, the message will be scheduled
1983 		 * after selection is complete.
1984 		 */
1985 		if (sc->sc_state == AIC_CONNECTED)
1986 			aic_sched_msgout(sc, SEND_ABORT);
1987 	} else {
1988 		aic_dequeue(sc, acb);
1989 		TAILQ_INSERT_HEAD(&sc->ready_list, acb, chain);
1990 		if (sc->sc_state == AIC_IDLE)
1991 			aic_sched(sc);
1992 	}
1993 }
1994 
1995 void
1996 aic_timeout(void *arg)
1997 {
1998 	struct aic_acb *acb = arg;
1999 	struct scsi_xfer *xs = acb->xs;
2000 	struct scsi_link *sc_link = xs->sc_link;
2001 	struct aic_softc *sc = sc_link->adapter_softc;
2002 	int s;
2003 
2004 	sc_print_addr(sc_link);
2005 	printf("timed out");
2006 
2007 	s = splbio();
2008 
2009 	if (acb->flags & ACB_ABORT) {
2010 		/* abort timed out */
2011 		printf(" AGAIN\n");
2012 		/* XXX Must reset! */
2013 	} else {
2014 		/* abort the operation that has timed out */
2015 		printf("\n");
2016 		acb->xs->error = XS_TIMEOUT;
2017 		aic_abort(sc, acb);
2018 	}
2019 
2020 	splx(s);
2021 }
2022 
2023 #ifdef AIC_DEBUG
2024 /*
2025  * The following functions are mostly used for debugging purposes, either
2026  * directly called from the driver or from the kernel debugger.
2027  */
2028 
2029 void
2030 aic_show_scsi_cmd(struct aic_acb *acb)
2031 {
2032 	u_char  *b = (u_char *)&acb->scsi_cmd;
2033 	struct scsi_link *sc_link = acb->xs->sc_link;
2034 	int i;
2035 
2036 	sc_print_addr(sc_link);
2037 	if ((acb->xs->flags & SCSI_RESET) == 0) {
2038 		for (i = 0; i < acb->scsi_cmd_length; i++) {
2039 			if (i)
2040 				printf(",");
2041 			printf("%x", b[i]);
2042 		}
2043 		printf("\n");
2044 	} else
2045 		printf("RESET\n");
2046 }
2047 
2048 void
2049 aic_print_acb(struct aic_acb *acb)
2050 {
2051 
2052 	printf("acb@%p xs=%p flags=%x", acb, acb->xs, acb->flags);
2053 	printf(" dp=%p dleft=%d target_stat=%x\n",
2054 	       acb->data_addr, acb->data_length, acb->target_stat);
2055 	aic_show_scsi_cmd(acb);
2056 }
2057 
2058 void
2059 aic_print_active_acb(void)
2060 {
2061 	struct aic_acb *acb;
2062 	struct aic_softc *sc = aic_cd.cd_devs[0];
2063 
2064 	printf("ready list:\n");
2065 	TAILQ_FOREACH(acb, &sc->ready_list, chain)
2066 		aic_print_acb(acb);
2067 	printf("nexus:\n");
2068 	if (sc->sc_nexus != NULL)
2069 		aic_print_acb(sc->sc_nexus);
2070 	printf("nexus list:\n");
2071 	TAILQ_FOREACH(acb, &sc->nexus_list, chain)
2072 		aic_print_acb(acb);
2073 }
2074 
2075 void
2076 aic_dump6360(struct aic_softc *sc)
2077 {
2078 	bus_space_tag_t iot = sc->sc_iot;
2079 	bus_space_handle_t ioh = sc->sc_ioh;
2080 
2081 	printf("aic6360: SCSISEQ=%x SXFRCTL0=%x SXFRCTL1=%x SCSISIG=%x\n",
2082 	    bus_space_read_1(iot, ioh, SCSISEQ),
2083 	    bus_space_read_1(iot, ioh, SXFRCTL0),
2084 	    bus_space_read_1(iot, ioh, SXFRCTL1),
2085 	    bus_space_read_1(iot, ioh, SCSISIG));
2086 	printf("         SSTAT0=%x SSTAT1=%x SSTAT2=%x SSTAT3=%x SSTAT4=%x\n",
2087 	    bus_space_read_1(iot, ioh, SSTAT0),
2088 	    bus_space_read_1(iot, ioh, SSTAT1),
2089 	    bus_space_read_1(iot, ioh, SSTAT2),
2090 	    bus_space_read_1(iot, ioh, SSTAT3),
2091 	    bus_space_read_1(iot, ioh, SSTAT4));
2092 	printf("         SIMODE0=%x SIMODE1=%x ",
2093 	    bus_space_read_1(iot, ioh, SIMODE0),
2094 	    bus_space_read_1(iot, ioh, SIMODE1));
2095 	printf("DMACNTRL0=%x DMACNTRL1=%x DMASTAT=%x\n",
2096 	    bus_space_read_1(iot, ioh, DMACNTRL0),
2097 	    bus_space_read_1(iot, ioh, DMACNTRL1),
2098 	    bus_space_read_1(iot, ioh, DMASTAT));
2099 	printf("         FIFOSTAT=%d SCSIBUS=0x%x\n",
2100 	    bus_space_read_1(iot, ioh, FIFOSTAT),
2101 	    bus_space_read_1(iot, ioh, SCSIBUS));
2102 }
2103 
2104 void
2105 aic_dump_driver(struct aic_softc *sc)
2106 {
2107 	struct aic_tinfo *ti;
2108 	int i;
2109 
2110 	printf("nexus=%p prevphase=%x\n", sc->sc_nexus, sc->sc_prevphase);
2111 	printf("state=%x msgin=%x ", sc->sc_state, sc->sc_imess[0]);
2112 	printf("msgpriq=%x msgoutq=%x lastmsg=%x currmsg=%x\n", sc->sc_msgpriq,
2113 	    sc->sc_msgoutq, sc->sc_lastmsg, sc->sc_currmsg);
2114 	for (i = 0; i < 7; i++) {
2115 		ti = &sc->sc_tinfo[i];
2116 		printf("tinfo%d: %d cmds %d disconnects %d timeouts",
2117 		    i, ti->cmds, ti->dconns, ti->touts);
2118 		printf(" %d senses flags=%x\n", ti->senses, ti->flags);
2119 	}
2120 }
2121 #endif
2122