xref: /netbsd-src/sys/dev/ic/ncr53c9x.c (revision cef8759bd76c1b621f8eab8faa6f208faabc2e15)
1 /*	$NetBSD: ncr53c9x.c,v 1.153 2020/04/13 00:27:17 chs Exp $	*/
2 
3 /*-
4  * Copyright (c) 1998, 2002 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Charles M. Hannum.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Copyright (c) 1994 Peter Galbavy
34  * Copyright (c) 1995 Paul Kranenburg
35  * All rights reserved.
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  * 3. All advertising materials mentioning features or use of this software
46  *    must display the following acknowledgement:
47  *	This product includes software developed by Peter Galbavy
48  * 4. The name of the author may not be used to endorse or promote products
49  *    derived from this software without specific prior written permission.
50  *
51  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
52  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
53  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
54  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
55  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
56  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
57  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
58  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
59  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
60  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
61  * POSSIBILITY OF SUCH DAMAGE.
62  */
63 
64 /*
65  * Based on aic6360 by Jarle Greipsland
66  *
67  * Acknowledgements: Many of the algorithms used in this driver are
68  * inspired by the work of Julian Elischer (julian@tfs.com) and
69  * Charles Hannum (mycroft@duality.gnu.ai.mit.edu).  Thanks a million!
70  */
71 
72 #include <sys/cdefs.h>
73 __KERNEL_RCSID(0, "$NetBSD: ncr53c9x.c,v 1.153 2020/04/13 00:27:17 chs Exp $");
74 
75 #include <sys/param.h>
76 #include <sys/systm.h>
77 #include <sys/callout.h>
78 #include <sys/kernel.h>
79 #include <sys/errno.h>
80 #include <sys/ioctl.h>
81 #include <sys/device.h>
82 #include <sys/buf.h>
83 #include <sys/malloc.h>
84 #include <sys/proc.h>
85 #include <sys/queue.h>
86 #include <sys/pool.h>
87 #include <sys/scsiio.h>
88 
89 #include <dev/scsipi/scsi_spc.h>
90 #include <dev/scsipi/scsi_all.h>
91 #include <dev/scsipi/scsipi_all.h>
92 #include <dev/scsipi/scsiconf.h>
93 #include <dev/scsipi/scsi_message.h>
94 
95 #include <dev/ic/ncr53c9xreg.h>
96 #include <dev/ic/ncr53c9xvar.h>
97 
98 int ncr53c9x_debug = NCR_SHOWMISC; /*NCR_SHOWPHASE|NCR_SHOWMISC|NCR_SHOWTRAC|NCR_SHOWCMDS;*/
99 #ifdef DEBUG
100 int ncr53c9x_notag = 0;
101 #endif
102 
103 static void	ncr53c9x_readregs(struct ncr53c9x_softc *);
104 static void	ncr53c9x_select(struct ncr53c9x_softc *, struct ncr53c9x_ecb *);
105 static int	ncr53c9x_reselect(struct ncr53c9x_softc *, int, int, int);
106 #if 0
107 static void	ncr53c9x_scsi_reset(struct ncr53c9x_softc *);
108 #endif
109 static void	ncr53c9x_clear(struct ncr53c9x_softc *, scsipi_xfer_result_t);
110 static int	ncr53c9x_poll(struct ncr53c9x_softc *,
111 			      struct scsipi_xfer *, int);
112 static void	ncr53c9x_sched(struct ncr53c9x_softc *);
113 static void	ncr53c9x_done(struct ncr53c9x_softc *, struct ncr53c9x_ecb *);
114 static void	ncr53c9x_msgin(struct ncr53c9x_softc *);
115 static void	ncr53c9x_msgout(struct ncr53c9x_softc *);
116 static void	ncr53c9x_timeout(void *arg);
117 static void	ncr53c9x_watch(void *arg);
118 static void	ncr53c9x_dequeue(struct ncr53c9x_softc *,
119 				 struct ncr53c9x_ecb *);
120 static int	ncr53c9x_ioctl(struct scsipi_channel *, u_long,
121 			       void *, int, struct proc *);
122 
123 void ncr53c9x_sense(struct ncr53c9x_softc *, struct ncr53c9x_ecb *);
124 void ncr53c9x_free_ecb(struct ncr53c9x_softc *, struct ncr53c9x_ecb *);
125 struct ncr53c9x_ecb *ncr53c9x_get_ecb(struct ncr53c9x_softc *, int);
126 
127 static inline int ncr53c9x_stp2cpb(struct ncr53c9x_softc *, int);
128 static inline void ncr53c9x_setsync(struct ncr53c9x_softc *,
129 				    struct ncr53c9x_tinfo *);
130 void   ncr53c9x_update_xfer_mode (struct ncr53c9x_softc *, int);
131 static struct ncr53c9x_linfo *ncr53c9x_lunsearch(struct ncr53c9x_tinfo *,
132 						 int64_t lun);
133 
134 static void ncr53c9x_wrfifo(struct ncr53c9x_softc *, uint8_t *, int);
135 
136 static int  ncr53c9x_rdfifo(struct ncr53c9x_softc *, int);
137 #define NCR_RDFIFO_START   0
138 #define NCR_RDFIFO_CONTINUE 1
139 
140 
141 #define NCR_SET_COUNT(sc, size) do { \
142 		NCR_WRITE_REG((sc), NCR_TCL, (size));			\
143 		NCR_WRITE_REG((sc), NCR_TCM, (size) >> 8);		\
144 		if ((sc->sc_cfg2 & NCRCFG2_FE) ||			\
145 		    (sc->sc_rev == NCR_VARIANT_FAS366)) {		\
146 			NCR_WRITE_REG((sc), NCR_TCH, (size) >> 16);	\
147 		}							\
148 		if (sc->sc_rev == NCR_VARIANT_FAS366) {			\
149 			NCR_WRITE_REG(sc, NCR_RCH, 0);			\
150 		}							\
151 } while (/* CONSTCOND */0)
152 
153 static int ecb_pool_initialized = 0;
154 static struct pool ecb_pool;
155 
156 /*
157  * Names for the NCR53c9x variants, corresponding to the variant tags
158  * in ncr53c9xvar.h.
159  */
160 static const char *ncr53c9x_variant_names[] = {
161 	"ESP100",
162 	"ESP100A",
163 	"ESP200",
164 	"NCR53C94",
165 	"NCR53C96",
166 	"ESP406",
167 	"FAS408",
168 	"FAS216",
169 	"AM53C974",
170 	"FAS366/HME",
171 	"NCR53C90 (86C01)",
172 };
173 
174 /*
175  * Search linked list for LUN info by LUN id.
176  */
177 static struct ncr53c9x_linfo *
178 ncr53c9x_lunsearch(struct ncr53c9x_tinfo *ti, int64_t lun)
179 {
180 	struct ncr53c9x_linfo *li;
181 
182 	LIST_FOREACH(li, &ti->luns, link)
183 		if (li->lun == lun)
184 			return li;
185 	return NULL;
186 }
187 
188 /*
189  * Attach this instance, and then all the sub-devices
190  */
191 void
192 ncr53c9x_attach(struct ncr53c9x_softc *sc)
193 {
194 	struct scsipi_adapter *adapt = &sc->sc_adapter;
195 	struct scsipi_channel *chan = &sc->sc_channel;
196 
197 	mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_BIO);
198 
199 	callout_init(&sc->sc_watchdog, 0);
200 
201 	/*
202 	 * Note, the front-end has set us up to print the chip variation.
203 	 */
204 	if (sc->sc_rev >= NCR_VARIANT_MAX) {
205 		aprint_error(": unknown variant %d, devices not attached\n",
206 		    sc->sc_rev);
207 		return;
208 	}
209 
210 	aprint_normal(": %s, %dMHz, SCSI ID %d\n",
211 	    ncr53c9x_variant_names[sc->sc_rev], sc->sc_freq, sc->sc_id);
212 
213 	sc->sc_ntarg = (sc->sc_rev == NCR_VARIANT_FAS366) ? 16 : 8;
214 
215 	/*
216 	 * Allocate SCSI message buffers.
217 	 * Front-ends can override allocation to avoid alignment
218 	 * handling in the DMA engines. Note that that ncr53c9x_msgout()
219 	 * can request a 1 byte DMA transfer.
220 	 */
221 	if (sc->sc_omess == NULL)
222 		sc->sc_omess = malloc(NCR_MAX_MSG_LEN, M_DEVBUF, M_WAITOK);
223 
224 	if (sc->sc_imess == NULL)
225 		sc->sc_imess = malloc(NCR_MAX_MSG_LEN + 1, M_DEVBUF, M_WAITOK);
226 
227 	sc->sc_tinfo = malloc(sc->sc_ntarg * sizeof(sc->sc_tinfo[0]),
228 	    M_DEVBUF, M_WAITOK | M_ZERO);
229 
230 	/*
231 	 * Treat NCR53C90 with the 86C01 DMA chip exactly as ESP100
232 	 * from now on.
233 	 */
234 	if (sc->sc_rev == NCR_VARIANT_NCR53C90_86C01)
235 		sc->sc_rev = NCR_VARIANT_ESP100;
236 
237 	sc->sc_ccf = FREQTOCCF(sc->sc_freq);
238 
239 	/* The value *must not* be == 1. Make it 2 */
240 	if (sc->sc_ccf == 1)
241 		sc->sc_ccf = 2;
242 
243 	/*
244 	 * The recommended timeout is 250ms. This register is loaded
245 	 * with a value calculated as follows, from the docs:
246 	 *
247 	 *		(timout period) x (CLK frequency)
248 	 *	reg = -------------------------------------
249 	 *		 8192 x (Clock Conversion Factor)
250 	 *
251 	 * Since CCF has a linear relation to CLK, this generally computes
252 	 * to the constant of 153.
253 	 */
254 	sc->sc_timeout = ((250 * 1000) * sc->sc_freq) / (8192 * sc->sc_ccf);
255 
256 	/* CCF register only has 3 bits; 0 is actually 8 */
257 	sc->sc_ccf &= 7;
258 
259 	/*
260 	 * Fill in the scsipi_adapter.
261 	 */
262 	adapt->adapt_dev = sc->sc_dev;
263 	adapt->adapt_nchannels = 1;
264 	adapt->adapt_openings = 256;
265 	adapt->adapt_max_periph = 256;
266 	adapt->adapt_ioctl = ncr53c9x_ioctl;
267 	/* adapt_request initialized by front-end */
268 	/* adapt_minphys initialized by front-end */
269 
270 	/*
271 	 * Fill in the scsipi_channel.
272 	 */
273 	memset(chan, 0, sizeof(*chan));
274 	chan->chan_adapter = adapt;
275 	chan->chan_bustype = &scsi_bustype;
276 	chan->chan_channel = 0;
277 	chan->chan_ntargets = sc->sc_ntarg;
278 	chan->chan_nluns = 8;
279 	chan->chan_id = sc->sc_id;
280 
281 	/*
282 	 * Add reference to adapter so that we drop the reference after
283 	 * config_found() to make sure the adapter is disabled.
284 	 */
285 	if (scsipi_adapter_addref(adapt) != 0) {
286 		aprint_error_dev(sc->sc_dev, "unable to enable controller\n");
287 		return;
288 	}
289 
290 	/* Reset state & bus */
291 	sc->sc_cfflags = device_cfdata(sc->sc_dev)->cf_flags;
292 	sc->sc_state = 0;
293 	ncr53c9x_init(sc, 0);	/* no bus reset yet, leave that to scsibus* */
294 
295 	/*
296 	 * Now try to attach all the sub-devices
297 	 */
298 	sc->sc_child = config_found(sc->sc_dev, &sc->sc_channel, scsiprint);
299 
300 	scsipi_adapter_delref(adapt);
301 	callout_reset(&sc->sc_watchdog, 60 * hz, ncr53c9x_watch, sc);
302 }
303 
304 int
305 ncr53c9x_detach(struct ncr53c9x_softc *sc, int flags)
306 {
307 	struct ncr53c9x_linfo *li, *nextli;
308 	int t;
309 	int error;
310 
311 	callout_stop(&sc->sc_watchdog);
312 
313 	if (sc->sc_tinfo) {
314 		/* Cancel all commands. */
315 		ncr53c9x_clear(sc, XS_DRIVER_STUFFUP);
316 
317 		/* Free logical units. */
318 		for (t = 0; t < sc->sc_ntarg; t++) {
319 			for (li = LIST_FIRST(&sc->sc_tinfo[t].luns); li;
320 			    li = nextli) {
321 				nextli = LIST_NEXT(li, link);
322 				free(li, M_DEVBUF);
323 			}
324 		}
325 	}
326 
327 	if (sc->sc_child) {
328 		error = config_detach(sc->sc_child, flags);
329 		if (error)
330 			return error;
331 	}
332 
333 	if (sc->sc_imess)
334 		free(sc->sc_imess, M_DEVBUF);
335 	if (sc->sc_omess)
336 		free(sc->sc_omess, M_DEVBUF);
337 
338 	mutex_destroy(&sc->sc_lock);
339 
340 	return 0;
341 }
342 
343 /*
344  * This is the generic ncr53c9x reset function. It does not reset the SCSI bus,
345  * only this controller, but kills any on-going commands, and also stops
346  * and resets the DMA.
347  *
348  * After reset, registers are loaded with the defaults from the attach
349  * routine above.
350  */
351 void
352 ncr53c9x_reset(struct ncr53c9x_softc *sc)
353 {
354 
355 	/* reset DMA first */
356 	NCRDMA_RESET(sc);
357 
358 	/* reset SCSI chip */
359 	NCRCMD(sc, NCRCMD_RSTCHIP);
360 	NCRCMD(sc, NCRCMD_NOP);
361 	DELAY(500);
362 
363 	/* do these backwards, and fall through */
364 	switch (sc->sc_rev) {
365 	case NCR_VARIANT_ESP406:
366 	case NCR_VARIANT_FAS408:
367 		NCR_WRITE_REG(sc, NCR_CFG5, sc->sc_cfg5 | NCRCFG5_SINT);
368 		NCR_WRITE_REG(sc, NCR_CFG4, sc->sc_cfg4);
369 		/* FALLTHROUGH */
370 	case NCR_VARIANT_AM53C974:
371 	case NCR_VARIANT_FAS216:
372 	case NCR_VARIANT_NCR53C94:
373 	case NCR_VARIANT_NCR53C96:
374 	case NCR_VARIANT_ESP200:
375 		sc->sc_features |= NCR_F_HASCFG3;
376 		NCR_WRITE_REG(sc, NCR_CFG3, sc->sc_cfg3);
377 		/* FALLTHROUGH */
378 	case NCR_VARIANT_ESP100A:
379 		sc->sc_features |= NCR_F_SELATN3;
380 		NCR_WRITE_REG(sc, NCR_CFG2, sc->sc_cfg2);
381 		/* FALLTHROUGH */
382 	case NCR_VARIANT_ESP100:
383 		NCR_WRITE_REG(sc, NCR_CFG1, sc->sc_cfg1);
384 		NCR_WRITE_REG(sc, NCR_CCF, sc->sc_ccf);
385 		NCR_WRITE_REG(sc, NCR_SYNCOFF, 0);
386 		NCR_WRITE_REG(sc, NCR_TIMEOUT, sc->sc_timeout);
387 		break;
388 
389 	case NCR_VARIANT_FAS366:
390 		sc->sc_features |=
391 		    NCR_F_HASCFG3 | NCR_F_FASTSCSI | NCR_F_SELATN3;
392 		sc->sc_cfg3 = NCRFASCFG3_FASTCLK | NCRFASCFG3_OBAUTO;
393 		sc->sc_cfg3_fscsi = NCRFASCFG3_FASTSCSI;
394 		NCR_WRITE_REG(sc, NCR_CFG3, sc->sc_cfg3);
395 		sc->sc_cfg2 = 0; /* NCRCFG2_HMEFE| NCRCFG2_HME32 */
396 		NCR_WRITE_REG(sc, NCR_CFG2, sc->sc_cfg2);
397 		NCR_WRITE_REG(sc, NCR_CFG1, sc->sc_cfg1);
398 		NCR_WRITE_REG(sc, NCR_CCF, sc->sc_ccf);
399 		NCR_WRITE_REG(sc, NCR_SYNCOFF, 0);
400 		NCR_WRITE_REG(sc, NCR_TIMEOUT, sc->sc_timeout);
401 		break;
402 
403 	default:
404 		printf("%s: unknown revision code, assuming ESP100\n",
405 		    device_xname(sc->sc_dev));
406 		NCR_WRITE_REG(sc, NCR_CFG1, sc->sc_cfg1);
407 		NCR_WRITE_REG(sc, NCR_CCF, sc->sc_ccf);
408 		NCR_WRITE_REG(sc, NCR_SYNCOFF, 0);
409 		NCR_WRITE_REG(sc, NCR_TIMEOUT, sc->sc_timeout);
410 	}
411 
412 	if (sc->sc_rev == NCR_VARIANT_AM53C974)
413 		NCR_WRITE_REG(sc, NCR_AMDCFG4, sc->sc_cfg4);
414 
415 #if 0
416 	printf("%s: ncr53c9x_reset: revision %d\n",
417 	    device_xname(sc->sc_dev), sc->sc_rev);
418 	printf("%s: ncr53c9x_reset: cfg1 0x%x, cfg2 0x%x, cfg3 0x%x, "
419 	    "ccf 0x%x, timeout 0x%x\n",
420 	    device_xname(sc->sc_dev), sc->sc_cfg1, sc->sc_cfg2, sc->sc_cfg3,
421 	    sc->sc_ccf, sc->sc_timeout);
422 #endif
423 }
424 
425 #if 0
426 /*
427  * Reset the SCSI bus, but not the chip
428  */
429 void
430 ncr53c9x_scsi_reset(struct ncr53c9x_softc *sc)
431 {
432 
433 	(*sc->sc_glue->gl_dma_stop)(sc);
434 
435 	printf("%s: resetting SCSI bus\n", device_xname(sc->sc_dev));
436 	NCRCMD(sc, NCRCMD_RSTSCSI);
437 }
438 #endif
439 
440 /*
441  * Clear all commands
442  */
443 void
444 ncr53c9x_clear(struct ncr53c9x_softc *sc, scsipi_xfer_result_t result)
445 {
446 	struct ncr53c9x_ecb *ecb;
447 	struct ncr53c9x_linfo *li;
448 	int i, r;
449 
450 	/* Cancel any active commands. */
451 	sc->sc_state = NCR_CLEANING;
452 	sc->sc_msgify = 0;
453 	ecb = sc->sc_nexus;
454 	if (ecb != NULL) {
455 		ecb->xs->error = result;
456 		ncr53c9x_done(sc, ecb);
457 	}
458 	/* Cancel outstanding disconnected commands on each LUN */
459 	for (r = 0; r < sc->sc_ntarg; r++) {
460 		LIST_FOREACH(li, &sc->sc_tinfo[r].luns, link) {
461 			ecb = li->untagged;
462 			if (ecb != NULL) {
463 				li->untagged = NULL;
464 				/*
465 				 * XXXXXXX
466 				 *
467 				 * Should we terminate a command
468 				 * that never reached the disk?
469 				 */
470 				li->busy = 0;
471 				ecb->xs->error = result;
472 				ncr53c9x_done(sc, ecb);
473 			}
474 			for (i = 0; i < 256; i++) {
475 				ecb = li->queued[i];
476 				if (ecb != NULL) {
477 					li->queued[i] = NULL;
478 					ecb->xs->error = result;
479 					ncr53c9x_done(sc, ecb);
480 				}
481 			}
482 			li->used = 0;
483 		}
484 	}
485 }
486 
487 /*
488  * Initialize ncr53c9x state machine
489  */
490 void
491 ncr53c9x_init(struct ncr53c9x_softc *sc, int doreset)
492 {
493 	int r;
494 
495 	NCR_MISC(("[NCR_INIT(%d) %d] ", doreset, sc->sc_state));
496 
497 	if (!ecb_pool_initialized) {
498 		/* All instances share this pool */
499 		pool_init(&ecb_pool, sizeof(struct ncr53c9x_ecb), 0, 0, 0,
500 		    "ncr53c9x_ecb", NULL, IPL_BIO);
501 		/* make sure to always have some items to play with */
502 		pool_prime(&ecb_pool, 1);
503 		ecb_pool_initialized = 1;
504 	}
505 
506 	if (sc->sc_state == 0) {
507 		/* First time through; initialize. */
508 
509 		TAILQ_INIT(&sc->ready_list);
510 		sc->sc_nexus = NULL;
511 		memset(sc->sc_tinfo, 0, sizeof(*sc->sc_tinfo));
512 		for (r = 0; r < sc->sc_ntarg; r++) {
513 			LIST_INIT(&sc->sc_tinfo[r].luns);
514 		}
515 	} else {
516 		ncr53c9x_clear(sc, XS_TIMEOUT);
517 	}
518 
519 	/*
520 	 * reset the chip to a known state
521 	 */
522 	ncr53c9x_reset(sc);
523 
524 	sc->sc_flags = 0;
525 	sc->sc_msgpriq = sc->sc_msgout = sc->sc_msgoutq = 0;
526 	sc->sc_phase = sc->sc_prevphase = INVALID_PHASE;
527 
528 	/* XXXSMP scsipi */
529 	KERNEL_LOCK(1, curlwp);
530 
531 	for (r = 0; r < sc->sc_ntarg; r++) {
532 		struct ncr53c9x_tinfo *ti = &sc->sc_tinfo[r];
533 /* XXX - config flags per target: low bits: no reselect; high bits: no synch */
534 
535 		ti->flags = ((sc->sc_minsync &&
536 		    !(sc->sc_cfflags & (1 << ((r & 7) + 8)))) ?
537 		    0 : T_SYNCHOFF) |
538 		    ((sc->sc_cfflags & (1 << (r & 7))) ? T_RSELECTOFF : 0);
539 #ifdef DEBUG
540 		if (ncr53c9x_notag)
541 			ti->flags &= ~T_TAG;
542 #endif
543 		ti->period = sc->sc_minsync;
544 		ti->offset = 0;
545 		ti->cfg3   = 0;
546 
547 		ncr53c9x_update_xfer_mode(sc, r);
548 	}
549 
550 	if (doreset) {
551 		sc->sc_state = NCR_SBR;
552 		NCRCMD(sc, NCRCMD_RSTSCSI);
553 
554 		/* Notify upper layer */
555 		scsipi_async_event(&sc->sc_channel, ASYNC_EVENT_RESET, NULL);
556 	} else {
557 		sc->sc_state = NCR_IDLE;
558 		ncr53c9x_sched(sc);
559 	}
560 
561 	/* XXXSMP scsipi */
562 	KERNEL_UNLOCK_ONE(curlwp);
563 }
564 
565 /*
566  * Read the NCR registers, and save their contents for later use.
567  * NCR_STAT, NCR_STEP & NCR_INTR are mostly zeroed out when reading
568  * NCR_INTR - so make sure it is the last read.
569  *
570  * I think that (from reading the docs) most bits in these registers
571  * only make sense when he DMA CSR has an interrupt showing. Call only
572  * if an interrupt is pending.
573  */
574 inline void
575 ncr53c9x_readregs(struct ncr53c9x_softc *sc)
576 {
577 
578 	sc->sc_espstat = NCR_READ_REG(sc, NCR_STAT);
579 	/* Only the stepo bits are of interest */
580 	sc->sc_espstep = NCR_READ_REG(sc, NCR_STEP) & NCRSTEP_MASK;
581 
582 	if (sc->sc_rev == NCR_VARIANT_FAS366)
583 		sc->sc_espstat2 = NCR_READ_REG(sc, NCR_STAT2);
584 
585 	sc->sc_espintr = NCR_READ_REG(sc, NCR_INTR);
586 
587 	if (sc->sc_glue->gl_clear_latched_intr != NULL)
588 		(*sc->sc_glue->gl_clear_latched_intr)(sc);
589 
590 	/*
591 	 * Determine the SCSI bus phase, return either a real SCSI bus phase
592 	 * or some pseudo phase we use to detect certain exceptions.
593 	 */
594 
595 	sc->sc_phase = (sc->sc_espintr & NCRINTR_DIS) ?
596 	    /* Disconnected */ BUSFREE_PHASE : sc->sc_espstat & NCRSTAT_PHASE;
597 
598 	NCR_INTS(("regs[intr=%02x,stat=%02x,step=%02x,stat2=%02x] ",
599 	    sc->sc_espintr, sc->sc_espstat, sc->sc_espstep, sc->sc_espstat2));
600 }
601 
602 /*
603  * Convert Synchronous Transfer Period to chip register Clock Per Byte value.
604  */
605 static inline int
606 ncr53c9x_stp2cpb(struct ncr53c9x_softc *sc, int period)
607 {
608 	int v;
609 
610 	v = (sc->sc_freq * period) / 250;
611 	if (ncr53c9x_cpb2stp(sc, v) < period)
612 		/* Correct round-down error */
613 		v++;
614 	return v;
615 }
616 
617 static inline void
618 ncr53c9x_setsync(struct ncr53c9x_softc *sc, struct ncr53c9x_tinfo *ti)
619 {
620 	uint8_t syncoff, synctp;
621 	uint8_t cfg3 = sc->sc_cfg3 | ti->cfg3;
622 
623 	if (ti->flags & T_SYNCMODE) {
624 		syncoff = ti->offset;
625 		synctp = ncr53c9x_stp2cpb(sc, ti->period);
626 		if (sc->sc_features & NCR_F_FASTSCSI) {
627 			/*
628 			 * If the period is 200ns or less (ti->period <= 50),
629 			 * put the chip in Fast SCSI mode.
630 			 */
631 			if (ti->period <= 50)
632 				/*
633 				 * There are (at least) 4 variations of the
634 				 * configuration 3 register.  The drive attach
635 				 * routine sets the appropriate bit to put the
636 				 * chip into Fast SCSI mode so that it doesn't
637 				 * have to be figured out here each time.
638 				 */
639 				cfg3 |= sc->sc_cfg3_fscsi;
640 		}
641 
642 		/*
643 		 * Am53c974 requires different SYNCTP values when the
644 		 * FSCSI bit is off.
645 		 */
646 		if (sc->sc_rev == NCR_VARIANT_AM53C974 &&
647 		    (cfg3 & NCRAMDCFG3_FSCSI) == 0)
648 			synctp--;
649 	} else {
650 		syncoff = 0;
651 		synctp = 0;
652 	}
653 
654 	if (sc->sc_features & NCR_F_HASCFG3)
655 		NCR_WRITE_REG(sc, NCR_CFG3, cfg3);
656 
657 	NCR_WRITE_REG(sc, NCR_SYNCOFF, syncoff);
658 	NCR_WRITE_REG(sc, NCR_SYNCTP, synctp);
659 }
660 
661 /*
662  * Send a command to a target, set the driver state to NCR_SELECTING
663  * and let the caller take care of the rest.
664  *
665  * Keeping this as a function allows me to say that this may be done
666  * by DMA instead of programmed I/O soon.
667  */
668 void
669 ncr53c9x_select(struct ncr53c9x_softc *sc, struct ncr53c9x_ecb *ecb)
670 {
671 	struct scsipi_periph *periph = ecb->xs->xs_periph;
672 	int target = periph->periph_target;
673 	int lun = periph->periph_lun;
674 	struct ncr53c9x_tinfo *ti = &sc->sc_tinfo[target];
675 	int tiflags = ti->flags;
676 	uint8_t *cmd;
677 	int clen;
678 	bool selatn3, selatns;
679 	size_t dmasize;
680 
681 	NCR_TRACE(("[ncr53c9x_select(t%d,l%d,cmd:%x,tag:%x,%x)] ",
682 	    target, lun, ecb->cmd.cmd.opcode, ecb->tag[0], ecb->tag[1]));
683 
684 	sc->sc_state = NCR_SELECTING;
685 	/*
686 	 * Schedule the timeout now, the first time we will go away
687 	 * expecting to come back due to an interrupt, because it is
688 	 * always possible that the interrupt may never happen.
689 	 */
690 	if ((ecb->xs->xs_control & XS_CTL_POLL) == 0) {
691 		callout_reset(&ecb->xs->xs_callout, mstohz(ecb->timeout),
692 		    ncr53c9x_timeout, ecb);
693 	}
694 
695 	/*
696 	 * The docs say the target register is never reset, and I
697 	 * can't think of a better place to set it
698 	 */
699 	if (sc->sc_rev == NCR_VARIANT_FAS366) {
700 		NCRCMD(sc, NCRCMD_FLUSH);
701 		NCR_WRITE_REG(sc, NCR_SELID, target | NCR_BUSID_HME);
702 	} else {
703 		NCR_WRITE_REG(sc, NCR_SELID, target);
704 	}
705 	ncr53c9x_setsync(sc, ti);
706 
707 	if ((ecb->flags & ECB_SENSE) != 0) {
708 		/*
709 		 * For REQUEST SENSE, we should not send an IDENTIFY or
710 		 * otherwise mangle the target.  There should be no MESSAGE IN
711 		 * phase.
712 		 */
713 		if (sc->sc_features & NCR_F_DMASELECT) {
714 			/* setup DMA transfer for command */
715 			dmasize = clen = ecb->clen;
716 			sc->sc_cmdlen = clen;
717 			sc->sc_cmdp = (void *)&ecb->cmd.cmd;
718 
719 			NCRDMA_SETUP(sc, &sc->sc_cmdp, &sc->sc_cmdlen, 0,
720 			    &dmasize);
721 			/* Program the SCSI counter */
722 			NCR_SET_COUNT(sc, dmasize);
723 
724 			if (sc->sc_rev != NCR_VARIANT_FAS366)
725 				NCRCMD(sc, NCRCMD_NOP | NCRCMD_DMA);
726 
727 			/* And get the targets attention */
728 			NCRCMD(sc, NCRCMD_SELNATN | NCRCMD_DMA);
729 			NCRDMA_GO(sc);
730 		} else {
731 			ncr53c9x_wrfifo(sc, (uint8_t *)&ecb->cmd.cmd,
732 			    ecb->clen);
733 			sc->sc_cmdlen = 0;
734 			NCRCMD(sc, NCRCMD_SELNATN);
735 		}
736 		return;
737 	}
738 
739 	selatn3 = selatns = false;
740 	if (ecb->tag[0] != 0) {
741 		if (sc->sc_features & NCR_F_SELATN3)
742 			/* use SELATN3 to send tag messages */
743 			selatn3 = true;
744 		else
745 			/* We don't have SELATN3; use SELATNS to send tags */
746 			selatns = true;
747 	}
748 
749 	if (ti->flags & T_NEGOTIATE) {
750 		/* We have to use SELATNS to send sync/wide messages */
751 		selatn3 = false;
752 		selatns = true;
753 	}
754 
755 	cmd = (uint8_t *)&ecb->cmd.cmd;
756 
757 	if (selatn3) {
758 		/* We'll use tags with SELATN3 */
759 		clen = ecb->clen + 3;
760 		cmd -= 3;
761 		cmd[0] = MSG_IDENTIFY(lun, 1);	/* msg[0] */
762 		cmd[1] = ecb->tag[0];		/* msg[1] */
763 		cmd[2] = ecb->tag[1];		/* msg[2] */
764 	} else {
765 		/* We don't have tags, or will send messages with SELATNS */
766 		clen = ecb->clen + 1;
767 		cmd -= 1;
768 		cmd[0] = MSG_IDENTIFY(lun, (tiflags & T_RSELECTOFF) == 0);
769 	}
770 
771 	if ((sc->sc_features & NCR_F_DMASELECT) && !selatns) {
772 
773 		/* setup DMA transfer for command */
774 		dmasize = clen;
775 		sc->sc_cmdlen = clen;
776 		sc->sc_cmdp = cmd;
777 
778 		NCRDMA_SETUP(sc, &sc->sc_cmdp, &sc->sc_cmdlen, 0, &dmasize);
779 		/* Program the SCSI counter */
780 		NCR_SET_COUNT(sc, dmasize);
781 
782 		/* load the count in */
783 		/* if (sc->sc_rev != NCR_VARIANT_FAS366) */
784 			NCRCMD(sc, NCRCMD_NOP | NCRCMD_DMA);
785 
786 		/* And get the targets attention */
787 		if (selatn3) {
788 			sc->sc_msgout = SEND_TAG;
789 			sc->sc_flags |= NCR_ATN;
790 			NCRCMD(sc, NCRCMD_SELATN3 | NCRCMD_DMA);
791 		} else
792 			NCRCMD(sc, NCRCMD_SELATN | NCRCMD_DMA);
793 		NCRDMA_GO(sc);
794 		return;
795 	}
796 
797 	/*
798 	 * Who am I. This is where we tell the target that we are
799 	 * happy for it to disconnect etc.
800 	 */
801 
802 	/* Now get the command into the FIFO */
803 	sc->sc_cmdlen = 0;
804 	ncr53c9x_wrfifo(sc, cmd, clen);
805 
806 	/* And get the targets attention */
807 	if (selatns) {
808 		NCR_MSGS(("SELATNS \n"));
809 		/* Arbitrate, select and stop after IDENTIFY message */
810 		NCRCMD(sc, NCRCMD_SELATNS);
811 	} else if (selatn3) {
812 		sc->sc_msgout = SEND_TAG;
813 		sc->sc_flags |= NCR_ATN;
814 		NCRCMD(sc, NCRCMD_SELATN3);
815 	} else
816 		NCRCMD(sc, NCRCMD_SELATN);
817 }
818 
819 void
820 ncr53c9x_free_ecb(struct ncr53c9x_softc *sc, struct ncr53c9x_ecb *ecb)
821 {
822 	int s;
823 
824 	s = splbio();
825 	ecb->flags = 0;
826 	pool_put(&ecb_pool, (void *)ecb);
827 	splx(s);
828 	return;
829 }
830 
831 struct ncr53c9x_ecb *
832 ncr53c9x_get_ecb(struct ncr53c9x_softc *sc, int flags)
833 {
834 	struct ncr53c9x_ecb *ecb;
835 	int s;
836 
837 	s = splbio();
838 	ecb = pool_get(&ecb_pool, PR_NOWAIT | PR_ZERO);
839 	if (ecb)
840 		ecb->flags |= ECB_ALLOC;
841 	splx(s);
842 	return ecb;
843 }
844 
845 /*
846  * DRIVER FUNCTIONS CALLABLE FROM HIGHER LEVEL DRIVERS
847  */
848 
849 /*
850  * Start a SCSI-command
851  * This function is called by the higher level SCSI-driver to queue/run
852  * SCSI-commands.
853  */
854 
855 void
856 ncr53c9x_scsipi_request(struct scsipi_channel *chan, scsipi_adapter_req_t req,
857     void *arg)
858 {
859 	struct scsipi_xfer *xs;
860 	struct scsipi_periph *periph;
861 	struct ncr53c9x_softc *sc;
862 	struct ncr53c9x_ecb *ecb;
863 	int flags;
864 
865 	NCR_TRACE(("[ncr53c9x_scsipi_request] "));
866 
867 	sc = device_private(chan->chan_adapter->adapt_dev);
868 	mutex_enter(&sc->sc_lock);
869 
870 	switch (req) {
871 	case ADAPTER_REQ_RUN_XFER:
872 		xs = arg;
873 		periph = xs->xs_periph;
874 		flags = xs->xs_control;
875 
876 		NCR_CMDS(("[0x%x, %d]->%d ", (int)xs->cmd->opcode, xs->cmdlen,
877 		    periph->periph_target));
878 
879 		/* Get an ECB to use. */
880 		ecb = ncr53c9x_get_ecb(sc, xs->xs_control);
881 		/*
882 		 * This should never happen as we track resources
883 		 * in the mid-layer, but for now it can as pool_get()
884 		 * can fail.
885 		 */
886 		if (ecb == NULL) {
887 			scsipi_printaddr(periph);
888 			printf("%s: unable to allocate ecb\n",
889 			    device_xname(sc->sc_dev));
890 			xs->error = XS_RESOURCE_SHORTAGE;
891 			mutex_exit(&sc->sc_lock);
892 			scsipi_done(xs);
893 			return;
894 		}
895 
896 		/* Initialize ecb */
897 		ecb->xs = xs;
898 		ecb->timeout = xs->timeout;
899 
900 		if (flags & XS_CTL_RESET) {
901 			ecb->flags |= ECB_RESET;
902 			ecb->clen = 0;
903 			ecb->dleft = 0;
904 		} else {
905 			memcpy(&ecb->cmd.cmd, xs->cmd, xs->cmdlen);
906 			ecb->clen = xs->cmdlen;
907 			ecb->daddr = xs->data;
908 			ecb->dleft = xs->datalen;
909 		}
910 		ecb->stat = 0;
911 
912 		TAILQ_INSERT_TAIL(&sc->ready_list, ecb, chain);
913 		ecb->flags |= ECB_READY;
914 		if (sc->sc_state == NCR_IDLE)
915 			ncr53c9x_sched(sc);
916 
917 		if ((flags & XS_CTL_POLL) == 0)
918 			break;
919 
920 		/* Not allowed to use interrupts, use polling instead */
921 		if (ncr53c9x_poll(sc, xs, ecb->timeout)) {
922 			ncr53c9x_timeout(ecb);
923 			if (ncr53c9x_poll(sc, xs, ecb->timeout))
924 				ncr53c9x_timeout(ecb);
925 		}
926 		break;
927 
928 	case ADAPTER_REQ_GROW_RESOURCES:
929 		/* XXX Not supported. */
930 		break;
931 
932 	case ADAPTER_REQ_SET_XFER_MODE:
933 	    {
934 		struct ncr53c9x_tinfo *ti;
935 		struct scsipi_xfer_mode *xm = arg;
936 
937 		ti = &sc->sc_tinfo[xm->xm_target];
938 		ti->flags &= ~(T_NEGOTIATE|T_SYNCMODE);
939 		ti->period = 0;
940 		ti->offset = 0;
941 
942 		if ((sc->sc_cfflags & (1 << ((xm->xm_target & 7) + 16))) == 0 &&
943 		    (xm->xm_mode & PERIPH_CAP_TQING)) {
944 			NCR_MISC(("%s: target %d: tagged queuing\n",
945 			    device_xname(sc->sc_dev), xm->xm_target));
946 			ti->flags |= T_TAG;
947 		} else
948 			ti->flags &= ~T_TAG;
949 
950 		if ((xm->xm_mode & PERIPH_CAP_WIDE16) != 0) {
951 			NCR_MISC(("%s: target %d: wide scsi negotiation\n",
952 			    device_xname(sc->sc_dev), xm->xm_target));
953 			if (sc->sc_rev == NCR_VARIANT_FAS366) {
954 				ti->flags |= T_WIDE;
955 				ti->width = 1;
956 			}
957 		}
958 
959 		if ((xm->xm_mode & PERIPH_CAP_SYNC) != 0 &&
960 		    (ti->flags & T_SYNCHOFF) == 0 && sc->sc_minsync != 0) {
961 			NCR_MISC(("%s: target %d: sync negotiation\n",
962 			    device_xname(sc->sc_dev), xm->xm_target));
963 			ti->flags |= T_NEGOTIATE;
964 			ti->period = sc->sc_minsync;
965 		}
966 		/*
967 		 * If we're not going to negotiate, send the notification
968 		 * now, since it won't happen later.
969 		 */
970 		if ((ti->flags & T_NEGOTIATE) == 0)
971 			ncr53c9x_update_xfer_mode(sc, xm->xm_target);
972 	    }
973 		break;
974 	}
975 
976 	mutex_exit(&sc->sc_lock);
977 }
978 
979 void
980 ncr53c9x_update_xfer_mode(struct ncr53c9x_softc *sc, int target)
981 {
982 	struct scsipi_xfer_mode xm;
983 	struct ncr53c9x_tinfo *ti = &sc->sc_tinfo[target];
984 
985 	xm.xm_target = target;
986 	xm.xm_mode = 0;
987 	xm.xm_period = 0;
988 	xm.xm_offset = 0;
989 
990 	if (ti->flags & T_SYNCMODE) {
991 		xm.xm_mode |= PERIPH_CAP_SYNC;
992 		xm.xm_period = ti->period;
993 		xm.xm_offset = ti->offset;
994 	}
995 	if (ti->width)
996 		xm.xm_mode |= PERIPH_CAP_WIDE16;
997 
998 	if ((ti->flags & (T_RSELECTOFF|T_TAG)) == T_TAG)
999 		xm.xm_mode |= PERIPH_CAP_TQING;
1000 
1001 	scsipi_async_event(&sc->sc_channel, ASYNC_EVENT_XFER_MODE, &xm);
1002 }
1003 
1004 /*
1005  * Used when interrupt driven I/O isn't allowed, e.g. during boot.
1006  */
1007 int
1008 ncr53c9x_poll(struct ncr53c9x_softc *sc, struct scsipi_xfer *xs, int count)
1009 {
1010 
1011 	NCR_TRACE(("[ncr53c9x_poll] "));
1012 	while (count) {
1013 		if (NCRDMA_ISINTR(sc)) {
1014 			mutex_exit(&sc->sc_lock);
1015 			ncr53c9x_intr(sc);
1016 			mutex_enter(&sc->sc_lock);
1017 		}
1018 #if alternatively
1019 		if (NCR_READ_REG(sc, NCR_STAT) & NCRSTAT_INT)
1020 			ncr53c9x_intr(sc);
1021 #endif
1022 		if ((xs->xs_status & XS_STS_DONE) != 0)
1023 			return 0;
1024 		if (sc->sc_state == NCR_IDLE) {
1025 			NCR_TRACE(("[ncr53c9x_poll: rescheduling] "));
1026 			ncr53c9x_sched(sc);
1027 		}
1028 		DELAY(1000);
1029 		count--;
1030 	}
1031 	return 1;
1032 }
1033 
1034 int
1035 ncr53c9x_ioctl(struct scsipi_channel *chan, u_long cmd, void *arg,
1036     int flag, struct proc *p)
1037 {
1038 	struct ncr53c9x_softc *sc;
1039 	int error = 0;
1040 
1041 	sc = device_private(chan->chan_adapter->adapt_dev);
1042 	switch (cmd) {
1043 	case SCBUSIORESET:
1044 		mutex_enter(&sc->sc_lock);
1045 		ncr53c9x_init(sc, 1);
1046 		mutex_exit(&sc->sc_lock);
1047 		break;
1048 	default:
1049 		error = ENOTTY;
1050 		break;
1051 	}
1052 	return error;
1053 }
1054 
1055 
1056 /*
1057  * LOW LEVEL SCSI UTILITIES
1058  */
1059 
1060 /*
1061  * Schedule a scsi operation.  This has now been pulled out of the interrupt
1062  * handler so that we may call it from ncr53c9x_scsipi_request and
1063  * ncr53c9x_done.  This may save us an unnecessary interrupt just to get
1064  * things going.  Should only be called when state == NCR_IDLE and at bio pl.
1065  */
1066 void
1067 ncr53c9x_sched(struct ncr53c9x_softc *sc)
1068 {
1069 	struct ncr53c9x_ecb *ecb;
1070 	struct scsipi_periph *periph;
1071 	struct ncr53c9x_tinfo *ti;
1072 	struct ncr53c9x_linfo *li;
1073 	int lun;
1074 	int tag;
1075 
1076 	NCR_TRACE(("[ncr53c9x_sched] "));
1077 	if (sc->sc_state != NCR_IDLE)
1078 		panic("%s: not IDLE (state=%d)", __func__, sc->sc_state);
1079 
1080 	/*
1081 	 * Find first ecb in ready queue that is for a target/lunit
1082 	 * combinations that is not busy.
1083 	 */
1084 	for (ecb = TAILQ_FIRST(&sc->ready_list); ecb != NULL;
1085 	    ecb = TAILQ_NEXT(ecb, chain)) {
1086 		periph = ecb->xs->xs_periph;
1087 		ti = &sc->sc_tinfo[periph->periph_target];
1088 		lun = periph->periph_lun;
1089 
1090 		/* Select type of tag for this command */
1091 		if ((ti->flags & T_RSELECTOFF) != 0)
1092 			tag = 0;
1093 		else if ((ti->flags & T_TAG) == 0)
1094 			tag = 0;
1095 		else if ((ecb->flags & ECB_SENSE) != 0)
1096 			tag = 0;
1097 		else
1098 			tag = ecb->xs->xs_tag_type;
1099 #if 0
1100 		/* XXXX Use tags for polled commands? */
1101 		if (ecb->xs->xs_control & XS_CTL_POLL)
1102 			tag = 0;
1103 #endif
1104 
1105 		li = TINFO_LUN(ti, lun);
1106 		if (li == NULL) {
1107 			/* Initialize LUN info and add to list. */
1108 			li = malloc(sizeof(*li), M_DEVBUF, M_NOWAIT|M_ZERO);
1109 			if (li == NULL) {
1110 				continue;
1111 			}
1112 			li->lun = lun;
1113 
1114 			LIST_INSERT_HEAD(&ti->luns, li, link);
1115 			if (lun < NCR_NLUN)
1116 				ti->lun[lun] = li;
1117 		}
1118 		li->last_used = time_second;
1119 		if (tag == 0) {
1120 			/* Try to issue this as an un-tagged command */
1121 			if (li->untagged == NULL)
1122 				li->untagged = ecb;
1123 		}
1124 		if (li->untagged != NULL) {
1125 			tag = 0;
1126 			if ((li->busy != 1) && li->used == 0) {
1127 				/* We need to issue this untagged command now */
1128 				ecb = li->untagged;
1129 				periph = ecb->xs->xs_periph;
1130 			} else {
1131 				/* Not ready yet */
1132 				continue;
1133 			}
1134 		}
1135 		ecb->tag[0] = tag;
1136 		if (tag != 0) {
1137 			li->queued[ecb->xs->xs_tag_id] = ecb;
1138 			ecb->tag[1] = ecb->xs->xs_tag_id;
1139 			li->used++;
1140 		}
1141 		if (li->untagged != NULL && (li->busy != 1)) {
1142 			li->busy = 1;
1143 			TAILQ_REMOVE(&sc->ready_list, ecb, chain);
1144 			ecb->flags &= ~ECB_READY;
1145 			sc->sc_nexus = ecb;
1146 			ncr53c9x_select(sc, ecb);
1147 			break;
1148 		}
1149 		if (li->untagged == NULL && tag != 0) {
1150 			TAILQ_REMOVE(&sc->ready_list, ecb, chain);
1151 			ecb->flags &= ~ECB_READY;
1152 			sc->sc_nexus = ecb;
1153 			ncr53c9x_select(sc, ecb);
1154 			break;
1155 		} else {
1156 			NCR_TRACE(("%d:%d busy\n",
1157 			    periph->periph_target,
1158 			    periph->periph_lun));
1159 		}
1160 	}
1161 }
1162 
1163 void
1164 ncr53c9x_sense(struct ncr53c9x_softc *sc, struct ncr53c9x_ecb *ecb)
1165 {
1166 	struct scsipi_xfer *xs = ecb->xs;
1167 	struct scsipi_periph *periph = xs->xs_periph;
1168 	struct ncr53c9x_tinfo *ti = &sc->sc_tinfo[periph->periph_target];
1169 	struct scsi_request_sense *ss = (void *)&ecb->cmd.cmd;
1170 	struct ncr53c9x_linfo *li;
1171 	int lun = periph->periph_lun;
1172 
1173 	NCR_TRACE(("requesting sense "));
1174 	/* Next, setup a request sense command block */
1175 	memset(ss, 0, sizeof(*ss));
1176 	ss->opcode = SCSI_REQUEST_SENSE;
1177 	ss->byte2 = periph->periph_lun << SCSI_CMD_LUN_SHIFT;
1178 	ss->length = sizeof(struct scsi_sense_data);
1179 	ecb->clen = sizeof(*ss);
1180 	ecb->daddr = (uint8_t *)&xs->sense.scsi_sense;
1181 	ecb->dleft = sizeof(struct scsi_sense_data);
1182 	ecb->flags |= ECB_SENSE;
1183 	ecb->timeout = NCR_SENSE_TIMEOUT;
1184 	ti->senses++;
1185 	li = TINFO_LUN(ti, lun);
1186 	if (li->busy)
1187 		li->busy = 0;
1188 	ncr53c9x_dequeue(sc, ecb);
1189 	li->untagged = ecb; /* must be executed first to fix C/A */
1190 	li->busy = 2;
1191 	if (ecb == sc->sc_nexus) {
1192 		ncr53c9x_select(sc, ecb);
1193 	} else {
1194 		TAILQ_INSERT_HEAD(&sc->ready_list, ecb, chain);
1195 		ecb->flags |= ECB_READY;
1196 		if (sc->sc_state == NCR_IDLE)
1197 			ncr53c9x_sched(sc);
1198 	}
1199 }
1200 
1201 /*
1202  * POST PROCESSING OF SCSI_CMD (usually current)
1203  */
1204 void
1205 ncr53c9x_done(struct ncr53c9x_softc *sc, struct ncr53c9x_ecb *ecb)
1206 {
1207 	struct scsipi_xfer *xs = ecb->xs;
1208 	struct scsipi_periph *periph = xs->xs_periph;
1209 	struct ncr53c9x_tinfo *ti = &sc->sc_tinfo[periph->periph_target];
1210 	int lun = periph->periph_lun;
1211 	struct ncr53c9x_linfo *li = TINFO_LUN(ti, lun);
1212 
1213 	NCR_TRACE(("[ncr53c9x_done(error:%x)] ", xs->error));
1214 
1215 	if ((xs->xs_control & XS_CTL_POLL) == 0)
1216 		callout_stop(&xs->xs_callout);
1217 
1218 	/*
1219 	 * Now, if we've come here with no error code, i.e. we've kept the
1220 	 * initial XS_NOERROR, and the status code signals that we should
1221 	 * check sense, we'll need to set up a request sense cmd block and
1222 	 * push the command back into the ready queue *before* any other
1223 	 * commands for this target/lunit, else we lose the sense info.
1224 	 * We don't support chk sense conditions for the request sense cmd.
1225 	 */
1226 	if (xs->error == XS_NOERROR) {
1227 		xs->status = ecb->stat;
1228 		if ((ecb->flags & ECB_ABORT) != 0) {
1229 			xs->error = XS_TIMEOUT;
1230 		} else if ((ecb->flags & ECB_SENSE) != 0) {
1231 			xs->error = XS_SENSE;
1232 		} else if ((ecb->stat & ST_MASK) == SCSI_CHECK) {
1233 			/* First, save the return values */
1234 			xs->resid = ecb->dleft;
1235 			ncr53c9x_sense(sc, ecb);
1236 			return;
1237 		} else {
1238 			xs->resid = ecb->dleft;
1239 		}
1240 		if (xs->status == SCSI_QUEUE_FULL || xs->status == XS_BUSY)
1241 			xs->error = XS_BUSY;
1242 	}
1243 
1244 #ifdef NCR53C9X_DEBUG
1245 	if (ncr53c9x_debug & NCR_SHOWTRAC) {
1246 		if (xs->resid != 0)
1247 			printf("resid=%d ", xs->resid);
1248 		if (xs->error == XS_SENSE)
1249 			printf("sense=0x%02x\n",
1250 			    xs->sense.scsi_sense.response_code);
1251 		else
1252 			printf("error=%d\n", xs->error);
1253 	}
1254 #endif
1255 
1256 	/*
1257 	 * Remove the ECB from whatever queue it's on.
1258 	 */
1259 	ncr53c9x_dequeue(sc, ecb);
1260 	if (ecb == sc->sc_nexus) {
1261 		sc->sc_nexus = NULL;
1262 		if (sc->sc_state != NCR_CLEANING) {
1263 			sc->sc_state = NCR_IDLE;
1264 			ncr53c9x_sched(sc);
1265 		}
1266 	}
1267 
1268 	if (xs->error == XS_SELTIMEOUT) {
1269 		/* Selection timeout -- discard this LUN if empty */
1270 		if (li->untagged == NULL && li->used == 0) {
1271 			if (lun < NCR_NLUN)
1272 				ti->lun[lun] = NULL;
1273 			LIST_REMOVE(li, link);
1274 			free(li, M_DEVBUF);
1275 		}
1276 	}
1277 
1278 	ncr53c9x_free_ecb(sc, ecb);
1279 	ti->cmds++;
1280 	mutex_exit(&sc->sc_lock);
1281 	scsipi_done(xs);
1282 	mutex_enter(&sc->sc_lock);
1283 }
1284 
1285 void
1286 ncr53c9x_dequeue(struct ncr53c9x_softc *sc, struct ncr53c9x_ecb *ecb)
1287 {
1288 	struct ncr53c9x_tinfo *ti =
1289 	    &sc->sc_tinfo[ecb->xs->xs_periph->periph_target];
1290 	struct ncr53c9x_linfo *li;
1291 	int64_t lun = ecb->xs->xs_periph->periph_lun;
1292 
1293 	li = TINFO_LUN(ti, lun);
1294 #ifdef DIAGNOSTIC
1295 	if (li == NULL || li->lun != lun)
1296 		panic("%s: lun %" PRIx64 " for ecb %p does not exist",
1297 		    __func__, lun, ecb);
1298 #endif
1299 	if (li->untagged == ecb) {
1300 		li->busy = 0;
1301 		li->untagged = NULL;
1302 	}
1303 	if (ecb->tag[0] && li->queued[ecb->tag[1]] != NULL) {
1304 #ifdef DIAGNOSTIC
1305 		if (li->queued[ecb->tag[1]] != NULL &&
1306 		    (li->queued[ecb->tag[1]] != ecb))
1307 			panic("%s: slot %d for lun %" PRIx64 " has %p "
1308 			    "instead of ecb %p\n", __func__, ecb->tag[1],
1309 			    lun,
1310 			    li->queued[ecb->tag[1]], ecb);
1311 #endif
1312 		li->queued[ecb->tag[1]] = NULL;
1313 		li->used--;
1314 	}
1315 
1316 	if ((ecb->flags & ECB_READY) != 0) {
1317 		ecb->flags &= ~ECB_READY;
1318 		TAILQ_REMOVE(&sc->ready_list, ecb, chain);
1319 	}
1320 }
1321 
1322 /*
1323  * INTERRUPT/PROTOCOL ENGINE
1324  */
1325 
1326 /*
1327  * Schedule an outgoing message by prioritizing it, and asserting
1328  * attention on the bus. We can only do this when we are the initiator
1329  * else there will be an illegal command interrupt.
1330  */
1331 #define ncr53c9x_sched_msgout(m) \
1332 	do {							\
1333 		NCR_MSGS(("ncr53c9x_sched_msgout %x %d", m, __LINE__));	\
1334 		NCRCMD(sc, NCRCMD_SETATN);			\
1335 		sc->sc_flags |= NCR_ATN;			\
1336 		sc->sc_msgpriq |= (m);				\
1337 	} while (/* CONSTCOND */0)
1338 
1339 static void
1340 ncr53c9x_flushfifo(struct ncr53c9x_softc *sc)
1341 {
1342 
1343 	NCR_TRACE(("[flushfifo] "));
1344 
1345 	NCRCMD(sc, NCRCMD_FLUSH);
1346 
1347 	if (sc->sc_phase == COMMAND_PHASE ||
1348 	    sc->sc_phase == MESSAGE_OUT_PHASE)
1349 		DELAY(2);
1350 }
1351 
1352 static int
1353 ncr53c9x_rdfifo(struct ncr53c9x_softc *sc, int how)
1354 {
1355 	int i, n;
1356 	uint8_t *ibuf;
1357 
1358 	switch (how) {
1359 	case NCR_RDFIFO_START:
1360 		ibuf = sc->sc_imess;
1361 		sc->sc_imlen = 0;
1362 		break;
1363 	case NCR_RDFIFO_CONTINUE:
1364 		ibuf = sc->sc_imess + sc->sc_imlen;
1365 		break;
1366 	default:
1367 		panic("%s: bad flag", __func__);
1368 		break;
1369 	}
1370 
1371 	/*
1372 	 * XXX buffer (sc_imess) size for message
1373 	 */
1374 
1375 	n = NCR_READ_REG(sc, NCR_FFLAG) & NCRFIFO_FF;
1376 
1377 	if (sc->sc_rev == NCR_VARIANT_FAS366) {
1378 		n *= 2;
1379 
1380 		for (i = 0; i < n; i++)
1381 			ibuf[i] = NCR_READ_REG(sc, NCR_FIFO);
1382 
1383 		if (sc->sc_espstat2 & NCRFAS_STAT2_ISHUTTLE) {
1384 
1385 			NCR_WRITE_REG(sc, NCR_FIFO, 0);
1386 			ibuf[i++] = NCR_READ_REG(sc, NCR_FIFO);
1387 
1388 			NCR_READ_REG(sc, NCR_FIFO);
1389 
1390 			ncr53c9x_flushfifo(sc);
1391 		}
1392 	} else {
1393 		for (i = 0; i < n; i++)
1394 			ibuf[i] = NCR_READ_REG(sc, NCR_FIFO);
1395 	}
1396 
1397 	sc->sc_imlen += i;
1398 
1399 #if 0
1400 #ifdef NCR53C9X_DEBUG
1401 	{
1402 		int j;
1403 
1404 		NCR_TRACE(("\n[rdfifo %s (%d):",
1405 		    (how == NCR_RDFIFO_START) ? "start" : "cont",
1406 		    (int)sc->sc_imlen));
1407 		if (ncr53c9x_debug & NCR_SHOWTRAC) {
1408 			for (j = 0; j < sc->sc_imlen; j++)
1409 				printf(" %02x", sc->sc_imess[j]);
1410 			printf("]\n");
1411 		}
1412 	}
1413 #endif
1414 #endif
1415 	return sc->sc_imlen;
1416 }
1417 
1418 static void
1419 ncr53c9x_wrfifo(struct ncr53c9x_softc *sc, uint8_t *p, int len)
1420 {
1421 	int i;
1422 
1423 #ifdef NCR53C9X_DEBUG
1424 	NCR_MSGS(("[wrfifo(%d):", len));
1425 	if (ncr53c9x_debug & NCR_SHOWMSGS) {
1426 		for (i = 0; i < len; i++)
1427 			printf(" %02x", p[i]);
1428 		printf("]\n");
1429 	}
1430 #endif
1431 
1432 	for (i = 0; i < len; i++) {
1433 		NCR_WRITE_REG(sc, NCR_FIFO, p[i]);
1434 
1435 		if (sc->sc_rev == NCR_VARIANT_FAS366)
1436 			NCR_WRITE_REG(sc, NCR_FIFO, 0);
1437 	}
1438 }
1439 
1440 int
1441 ncr53c9x_reselect(struct ncr53c9x_softc *sc, int message, int tagtype,
1442     int tagid)
1443 {
1444 	uint8_t selid, target, lun;
1445 	struct ncr53c9x_ecb *ecb = NULL;
1446 	struct ncr53c9x_tinfo *ti;
1447 	struct ncr53c9x_linfo *li;
1448 
1449 	if (sc->sc_rev == NCR_VARIANT_FAS366) {
1450 		target = sc->sc_selid;
1451 	} else {
1452 		/*
1453 		 * The SCSI chip made a snapshot of the data bus
1454 		 * while the reselection was being negotiated.
1455 		 * This enables us to determine which target did
1456 		 * the reselect.
1457 		 */
1458 		selid = sc->sc_selid & ~(1 << sc->sc_id);
1459 		if (selid & (selid - 1)) {
1460 			printf("%s: reselect with invalid selid %02x;"
1461 			    " sending DEVICE RESET\n",
1462 			    device_xname(sc->sc_dev), selid);
1463 			goto reset;
1464 		}
1465 
1466 		target = ffs(selid) - 1;
1467 	}
1468 	lun = message & 0x07;
1469 
1470 	/*
1471 	 * Search wait queue for disconnected cmd
1472 	 * The list should be short, so I haven't bothered with
1473 	 * any more sophisticated structures than a simple
1474 	 * singly linked list.
1475 	 */
1476 	ti = &sc->sc_tinfo[target];
1477 	li = TINFO_LUN(ti, lun);
1478 
1479 	/*
1480 	 * We can get as far as the LUN with the IDENTIFY
1481 	 * message.  Check to see if we're running an
1482 	 * un-tagged command.  Otherwise ack the IDENTIFY
1483 	 * and wait for a tag message.
1484 	 */
1485 	if (li != NULL) {
1486 		if (li->untagged != NULL && li->busy)
1487 			ecb = li->untagged;
1488 		else if (tagtype != MSG_SIMPLE_Q_TAG) {
1489 			/* Wait for tag to come by */
1490 			sc->sc_state = NCR_IDENTIFIED;
1491 			return 0;
1492 		} else if (tagtype)
1493 			ecb = li->queued[tagid];
1494 	}
1495 	if (ecb == NULL) {
1496 		printf("%s: reselect from target %d lun %d tag %x:%x "
1497 		    "with no nexus; sending ABORT\n",
1498 		    device_xname(sc->sc_dev), target, lun, tagtype, tagid);
1499 		goto abort;
1500 	}
1501 
1502 	/* Make this nexus active again. */
1503 	sc->sc_state = NCR_CONNECTED;
1504 	sc->sc_nexus = ecb;
1505 	ncr53c9x_setsync(sc, ti);
1506 
1507 	if (ecb->flags & ECB_RESET)
1508 		ncr53c9x_sched_msgout(SEND_DEV_RESET);
1509 	else if (ecb->flags & ECB_ABORT)
1510 		ncr53c9x_sched_msgout(SEND_ABORT);
1511 
1512 	/* Do an implicit RESTORE POINTERS. */
1513 	sc->sc_dp = ecb->daddr;
1514 	sc->sc_dleft = ecb->dleft;
1515 
1516 	return 0;
1517 
1518 reset:
1519 	ncr53c9x_sched_msgout(SEND_DEV_RESET);
1520 	return 1;
1521 
1522 abort:
1523 	ncr53c9x_sched_msgout(SEND_ABORT);
1524 	return 1;
1525 }
1526 
1527 static inline int
1528 __verify_msg_format(uint8_t *p, int len)
1529 {
1530 
1531 	if (len == 1 && MSG_IS1BYTE(p[0]))
1532 		return 1;
1533 	if (len == 2 && MSG_IS2BYTE(p[0]))
1534 		return 1;
1535 	if (len >= 3 && MSG_ISEXTENDED(p[0]) &&
1536 	    len == p[1] + 2)
1537 		return 1;
1538 
1539 	return 0;
1540 }
1541 
1542 /*
1543  * Get an incoming message as initiator.
1544  *
1545  * The SCSI bus must already be in MESSAGE_IN_PHASE and there is a
1546  * byte in the FIFO
1547  */
1548 void
1549 ncr53c9x_msgin(struct ncr53c9x_softc *sc)
1550 {
1551 
1552 	NCR_TRACE(("[ncr53c9x_msgin(curmsglen:%ld)] ", (long)sc->sc_imlen));
1553 
1554 	if (sc->sc_imlen == 0) {
1555 		printf("%s: msgin: no msg byte available\n",
1556 		    device_xname(sc->sc_dev));
1557 		return;
1558 	}
1559 
1560 	/*
1561 	 * Prepare for a new message.  A message should (according
1562 	 * to the SCSI standard) be transmitted in one single
1563 	 * MESSAGE_IN_PHASE. If we have been in some other phase,
1564 	 * then this is a new message.
1565 	 */
1566 	if (sc->sc_prevphase != MESSAGE_IN_PHASE &&
1567 	    sc->sc_state != NCR_RESELECTED) {
1568 		printf("%s: phase change, dropping message, "
1569 		    "prev %d, state %d\n",
1570 		    device_xname(sc->sc_dev), sc->sc_prevphase, sc->sc_state);
1571 		sc->sc_flags &= ~NCR_DROP_MSGI;
1572 		sc->sc_imlen = 0;
1573 	}
1574 
1575 	/*
1576 	 * If we're going to reject the message, don't bother storing
1577 	 * the incoming bytes.  But still, we need to ACK them.
1578 	 */
1579 	if ((sc->sc_flags & NCR_DROP_MSGI) != 0) {
1580 		NCRCMD(sc, NCRCMD_MSGOK);
1581 		printf("<dropping msg byte %x>", sc->sc_imess[sc->sc_imlen]);
1582 		return;
1583 	}
1584 
1585 	if (sc->sc_imlen >= NCR_MAX_MSG_LEN) {
1586 		ncr53c9x_sched_msgout(SEND_REJECT);
1587 		sc->sc_flags |= NCR_DROP_MSGI;
1588 	} else {
1589 		uint8_t *pb;
1590 		int plen;
1591 
1592 		switch (sc->sc_state) {
1593 		/*
1594 		 * if received message is the first of reselection
1595 		 * then first byte is selid, and then message
1596 		 */
1597 		case NCR_RESELECTED:
1598 			pb = sc->sc_imess + 1;
1599 			plen = sc->sc_imlen - 1;
1600 			break;
1601 		default:
1602 			pb = sc->sc_imess;
1603 			plen = sc->sc_imlen;
1604 			break;
1605 		}
1606 
1607 		if (__verify_msg_format(pb, plen))
1608 			goto gotit;
1609 	}
1610 
1611 	/* Ack what we have so far */
1612 	NCRCMD(sc, NCRCMD_MSGOK);
1613 	return;
1614 
1615 gotit:
1616 	NCR_MSGS(("gotmsg(%x) state %d", sc->sc_imess[0], sc->sc_state));
1617 	/* we got complete message, flush the imess, */
1618 	/* XXX nobody uses imlen below */
1619 	sc->sc_imlen = 0;
1620 	/*
1621 	 * Now we should have a complete message (1 byte, 2 byte
1622 	 * and moderately long extended messages).  We only handle
1623 	 * extended messages which total length is shorter than
1624 	 * NCR_MAX_MSG_LEN.  Longer messages will be amputated.
1625 	 */
1626 	switch (sc->sc_state) {
1627 		struct ncr53c9x_ecb *ecb;
1628 		struct ncr53c9x_tinfo *ti;
1629 		struct ncr53c9x_linfo *li;
1630 		int lun;
1631 
1632 	case NCR_CONNECTED:
1633 		ecb = sc->sc_nexus;
1634 		ti = &sc->sc_tinfo[ecb->xs->xs_periph->periph_target];
1635 
1636 		switch (sc->sc_imess[0]) {
1637 		case MSG_CMDCOMPLETE:
1638 			NCR_MSGS(("cmdcomplete "));
1639 			if (sc->sc_dleft < 0) {
1640 				scsipi_printaddr(ecb->xs->xs_periph);
1641 				printf("%s: got %ld extra bytes\n",
1642 				    device_xname(sc->sc_dev),
1643 				    -(long)sc->sc_dleft);
1644 				sc->sc_dleft = 0;
1645 			}
1646 			ecb->dleft = (ecb->flags & ECB_TENTATIVE_DONE) ?
1647 			    0 : sc->sc_dleft;
1648 			if ((ecb->flags & ECB_SENSE) == 0)
1649 				ecb->xs->resid = ecb->dleft;
1650 			sc->sc_state = NCR_CMDCOMPLETE;
1651 			break;
1652 
1653 		case MSG_MESSAGE_REJECT:
1654 			NCR_MSGS(("msg reject (msgout=%x) ", sc->sc_msgout));
1655 			switch (sc->sc_msgout) {
1656 			case SEND_TAG:
1657 				/*
1658 				 * Target does not like tagged queuing.
1659 				 *  - Flush the command queue
1660 				 *  - Disable tagged queuing for the target
1661 				 *  - Dequeue ecb from the queued array.
1662 				 */
1663 				printf("%s: tagged queuing rejected: "
1664 				    "target %d\n",
1665 				    device_xname(sc->sc_dev),
1666 				    ecb->xs->xs_periph->periph_target);
1667 
1668 				NCR_MSGS(("(rejected sent tag)"));
1669 				NCRCMD(sc, NCRCMD_FLUSH);
1670 				DELAY(1);
1671 				ti->flags &= ~T_TAG;
1672 				lun = ecb->xs->xs_periph->periph_lun;
1673 				li = TINFO_LUN(ti, lun);
1674 				if (ecb->tag[0] &&
1675 				    li->queued[ecb->tag[1]] != NULL) {
1676 					li->queued[ecb->tag[1]] = NULL;
1677 					li->used--;
1678 				}
1679 				ecb->tag[0] = ecb->tag[1] = 0;
1680 				li->untagged = ecb;
1681 				li->busy = 1;
1682 				break;
1683 
1684 			case SEND_SDTR:
1685 				printf("%s: sync transfer rejected: "
1686 				    "target %d\n",
1687 				    device_xname(sc->sc_dev),
1688 				    ecb->xs->xs_periph->periph_target);
1689 
1690 				sc->sc_flags &= ~NCR_SYNCHNEGO;
1691 				ti->flags &= ~(T_NEGOTIATE | T_SYNCMODE);
1692 				ncr53c9x_setsync(sc, ti);
1693 				ncr53c9x_update_xfer_mode(sc,
1694 				    ecb->xs->xs_periph->periph_target);
1695 				break;
1696 
1697 			case SEND_WDTR:
1698 				printf("%s: wide transfer rejected: "
1699 				    "target %d\n",
1700 				    device_xname(sc->sc_dev),
1701 				    ecb->xs->xs_periph->periph_target);
1702 				ti->flags &= ~(T_WIDE | T_WDTRSENT);
1703 				ti->width = 0;
1704 				break;
1705 
1706 			case SEND_INIT_DET_ERR:
1707 				goto abort;
1708 			}
1709 			break;
1710 
1711 		case MSG_NOOP:
1712 			NCR_MSGS(("noop "));
1713 			break;
1714 
1715 		case MSG_HEAD_OF_Q_TAG:
1716 		case MSG_SIMPLE_Q_TAG:
1717 		case MSG_ORDERED_Q_TAG:
1718 			NCR_MSGS(("TAG %x:%x",
1719 			    sc->sc_imess[0], sc->sc_imess[1]));
1720 			break;
1721 
1722 		case MSG_DISCONNECT:
1723 			NCR_MSGS(("disconnect "));
1724 			ti->dconns++;
1725 			sc->sc_state = NCR_DISCONNECT;
1726 
1727 			/*
1728 			 * Mark the fact that all bytes have moved. The
1729 			 * target may not bother to do a SAVE POINTERS
1730 			 * at this stage. This flag will set the residual
1731 			 * count to zero on MSG COMPLETE.
1732 			 */
1733 			if (sc->sc_dleft == 0)
1734 				ecb->flags |= ECB_TENTATIVE_DONE;
1735 
1736 			break;
1737 
1738 		case MSG_SAVEDATAPOINTER:
1739 			NCR_MSGS(("save datapointer "));
1740 			ecb->daddr = sc->sc_dp;
1741 			ecb->dleft = sc->sc_dleft;
1742 			break;
1743 
1744 		case MSG_RESTOREPOINTERS:
1745 			NCR_MSGS(("restore datapointer "));
1746 			sc->sc_dp = ecb->daddr;
1747 			sc->sc_dleft = ecb->dleft;
1748 			break;
1749 
1750 		case MSG_EXTENDED:
1751 			NCR_MSGS(("extended(%x) ", sc->sc_imess[2]));
1752 			switch (sc->sc_imess[2]) {
1753 			case MSG_EXT_SDTR:
1754 				NCR_MSGS(("SDTR period %d, offset %d ",
1755 				    sc->sc_imess[3], sc->sc_imess[4]));
1756 				if (sc->sc_imess[1] != 3)
1757 					goto reject;
1758 				ti->period = sc->sc_imess[3];
1759 				ti->offset = sc->sc_imess[4];
1760 				ti->flags &= ~T_NEGOTIATE;
1761 				if (sc->sc_minsync == 0 ||
1762 				    ti->offset == 0 ||
1763 				    ti->period > 124) {
1764 #if 0
1765 #ifdef NCR53C9X_DEBUG
1766 					scsipi_printaddr(ecb->xs->xs_periph);
1767 					printf("async mode\n");
1768 #endif
1769 #endif
1770 					ti->flags &= ~T_SYNCMODE;
1771 					if ((sc->sc_flags&NCR_SYNCHNEGO) == 0) {
1772 						/*
1773 						 * target initiated negotiation
1774 						 */
1775 						ti->offset = 0;
1776 						ncr53c9x_sched_msgout(
1777 						    SEND_SDTR);
1778 					}
1779 				} else {
1780 					int p;
1781 
1782 					p = ncr53c9x_stp2cpb(sc, ti->period);
1783 					ti->period = ncr53c9x_cpb2stp(sc, p);
1784 					if ((sc->sc_flags&NCR_SYNCHNEGO) == 0) {
1785 						/*
1786 						 * target initiated negotiation
1787 						 */
1788 						if (ti->period <
1789 						    sc->sc_minsync)
1790 							ti->period =
1791 							    sc->sc_minsync;
1792 						if (ti->offset > 15)
1793 							ti->offset = 15;
1794 						ti->flags &= ~T_SYNCMODE;
1795 						ncr53c9x_sched_msgout(
1796 						    SEND_SDTR);
1797 					} else {
1798 						/* we are sync */
1799 						ti->flags |= T_SYNCMODE;
1800 					}
1801 				}
1802 				ncr53c9x_update_xfer_mode(sc,
1803 				    ecb->xs->xs_periph->periph_target);
1804 				sc->sc_flags &= ~NCR_SYNCHNEGO;
1805 				ncr53c9x_setsync(sc, ti);
1806 				break;
1807 
1808 			case MSG_EXT_WDTR:
1809 #ifdef NCR53C9X_DEBUG
1810 				printf("%s: wide mode %d\n",
1811 				    device_xname(sc->sc_dev), sc->sc_imess[3]);
1812 #endif
1813 				if (sc->sc_imess[3] == 1) {
1814 					ti->cfg3 |= NCRFASCFG3_EWIDE;
1815 					ncr53c9x_setsync(sc, ti);
1816 				} else
1817 					ti->width = 0;
1818 				/*
1819 				 * Device started width negotiation.
1820 				 */
1821 				if ((ti->flags & T_WDTRSENT) == 0)
1822 					ncr53c9x_sched_msgout(SEND_WDTR);
1823 				ti->flags &= ~(T_WIDE | T_WDTRSENT);
1824 				break;
1825 			default:
1826 				scsipi_printaddr(ecb->xs->xs_periph);
1827 				printf("%s: unrecognized MESSAGE EXTENDED;"
1828 				    " sending REJECT\n",
1829 				    device_xname(sc->sc_dev));
1830 				goto reject;
1831 			}
1832 			break;
1833 		case MSG_IGN_WIDE_RESIDUE:
1834 			NCR_MSGS(("ignore wide residue "));
1835 			break;
1836 
1837 		default:
1838 			NCR_MSGS(("ident "));
1839 			scsipi_printaddr(ecb->xs->xs_periph);
1840 			printf("%s: unrecognized MESSAGE (%x); sending REJECT\n",
1841 			    device_xname(sc->sc_dev), sc->sc_imess[0]);
1842 		reject:
1843 			ncr53c9x_sched_msgout(SEND_REJECT);
1844 			break;
1845 		}
1846 		break;
1847 
1848 	case NCR_IDENTIFIED:
1849 		/*
1850 		 * IDENTIFY message was received and queue tag is expected now
1851 		 */
1852 		if ((sc->sc_imess[0] != MSG_SIMPLE_Q_TAG) ||
1853 		    (sc->sc_msgify == 0)) {
1854 			printf("%s: TAG reselect without IDENTIFY;"
1855 			    " MSG %x;"
1856 			    " sending DEVICE RESET\n",
1857 			    device_xname(sc->sc_dev),
1858 			    sc->sc_imess[0]);
1859 			goto reset;
1860 		}
1861 		(void)ncr53c9x_reselect(sc, sc->sc_msgify,
1862 		    sc->sc_imess[0], sc->sc_imess[1]);
1863 		break;
1864 
1865 	case NCR_RESELECTED:
1866 		if (MSG_ISIDENTIFY(sc->sc_imess[1])) {
1867 			sc->sc_msgify = sc->sc_imess[1];
1868 		} else {
1869 			printf("%s: reselect without IDENTIFY;"
1870 			    " MSG %x;"
1871 			    " sending DEVICE RESET\n",
1872 			    device_xname(sc->sc_dev),
1873 			    sc->sc_imess[1]);
1874 			goto reset;
1875 		}
1876 		(void)ncr53c9x_reselect(sc, sc->sc_msgify, 0, 0);
1877 		break;
1878 
1879 	default:
1880 		printf("%s: unexpected MESSAGE IN; sending DEVICE RESET\n",
1881 		    device_xname(sc->sc_dev));
1882 	reset:
1883 		ncr53c9x_sched_msgout(SEND_DEV_RESET);
1884 		break;
1885 
1886 	abort:
1887 		ncr53c9x_sched_msgout(SEND_ABORT);
1888 		break;
1889 	}
1890 
1891 	/* if we have more messages to send set ATN */
1892 	if (sc->sc_msgpriq)
1893 		NCRCMD(sc, NCRCMD_SETATN);
1894 
1895 	/* Ack last message byte */
1896 	NCRCMD(sc, NCRCMD_MSGOK);
1897 
1898 	/* Done, reset message pointer. */
1899 	sc->sc_flags &= ~NCR_DROP_MSGI;
1900 	sc->sc_imlen = 0;
1901 }
1902 
1903 
1904 /*
1905  * Send the highest priority, scheduled message
1906  */
1907 void
1908 ncr53c9x_msgout(struct ncr53c9x_softc *sc)
1909 {
1910 	struct ncr53c9x_tinfo *ti;
1911 	struct ncr53c9x_ecb *ecb;
1912 	size_t size;
1913 
1914 	NCR_TRACE(("[ncr53c9x_msgout(priq:%x, prevphase:%x)]",
1915 	    sc->sc_msgpriq, sc->sc_prevphase));
1916 
1917 	/*
1918 	 * XXX - the NCR_ATN flag is not in sync with the actual ATN
1919 	 *	 condition on the SCSI bus. The 53c9x chip
1920 	 *	 automatically turns off ATN before sending the
1921 	 *	 message byte.  (see also the comment below in the
1922 	 *	 default case when picking out a message to send)
1923 	 */
1924 	if (sc->sc_flags & NCR_ATN) {
1925 		if (sc->sc_prevphase != MESSAGE_OUT_PHASE) {
1926 		new:
1927 			NCRCMD(sc, NCRCMD_FLUSH);
1928 #if 0
1929 			DELAY(1);
1930 #endif
1931 			sc->sc_msgoutq = 0;
1932 			sc->sc_omlen = 0;
1933 		}
1934 	} else {
1935 		if (sc->sc_prevphase == MESSAGE_OUT_PHASE) {
1936 			ncr53c9x_sched_msgout(sc->sc_msgoutq);
1937 			goto new;
1938 		} else {
1939 			printf("%s at line %d: unexpected MESSAGE OUT phase\n",
1940 			    device_xname(sc->sc_dev), __LINE__);
1941 		}
1942 	}
1943 
1944 	if (sc->sc_omlen == 0) {
1945 		/* Pick up highest priority message */
1946 		sc->sc_msgout = sc->sc_msgpriq & -sc->sc_msgpriq;
1947 		sc->sc_msgoutq |= sc->sc_msgout;
1948 		sc->sc_msgpriq &= ~sc->sc_msgout;
1949 		sc->sc_omlen = 1;		/* "Default" message len */
1950 		switch (sc->sc_msgout) {
1951 		case SEND_SDTR:
1952 			ecb = sc->sc_nexus;
1953 			ti = &sc->sc_tinfo[ecb->xs->xs_periph->periph_target];
1954 			sc->sc_omess[0] = MSG_EXTENDED;
1955 			sc->sc_omess[1] = MSG_EXT_SDTR_LEN;
1956 			sc->sc_omess[2] = MSG_EXT_SDTR;
1957 			sc->sc_omess[3] = ti->period;
1958 			sc->sc_omess[4] = ti->offset;
1959 			sc->sc_omlen = 5;
1960 			if ((sc->sc_flags & NCR_SYNCHNEGO) == 0) {
1961 				ti->flags |= T_SYNCMODE;
1962 				ncr53c9x_setsync(sc, ti);
1963 			}
1964 			break;
1965 		case SEND_WDTR:
1966 			ecb = sc->sc_nexus;
1967 			ti = &sc->sc_tinfo[ecb->xs->xs_periph->periph_target];
1968 			sc->sc_omess[0] = MSG_EXTENDED;
1969 			sc->sc_omess[1] = MSG_EXT_WDTR_LEN;
1970 			sc->sc_omess[2] = MSG_EXT_WDTR;
1971 			sc->sc_omess[3] = ti->width;
1972 			sc->sc_omlen = 4;
1973 			break;
1974 		case SEND_IDENTIFY:
1975 			if (sc->sc_state != NCR_CONNECTED) {
1976 				printf("%s at line %d: no nexus\n",
1977 				    device_xname(sc->sc_dev), __LINE__);
1978 			}
1979 			ecb = sc->sc_nexus;
1980 			sc->sc_omess[0] =
1981 			    MSG_IDENTIFY(ecb->xs->xs_periph->periph_lun, 0);
1982 			break;
1983 		case SEND_TAG:
1984 			if (sc->sc_state != NCR_CONNECTED) {
1985 				printf("%s at line %d: no nexus\n",
1986 				    device_xname(sc->sc_dev), __LINE__);
1987 			}
1988 			ecb = sc->sc_nexus;
1989 			sc->sc_omess[0] = ecb->tag[0];
1990 			sc->sc_omess[1] = ecb->tag[1];
1991 			sc->sc_omlen = 2;
1992 			break;
1993 		case SEND_DEV_RESET:
1994 			sc->sc_flags |= NCR_ABORTING;
1995 			sc->sc_omess[0] = MSG_BUS_DEV_RESET;
1996 			ecb = sc->sc_nexus;
1997 			ti = &sc->sc_tinfo[ecb->xs->xs_periph->periph_target];
1998 			ti->flags &= ~T_SYNCMODE;
1999 			ncr53c9x_update_xfer_mode(sc,
2000 			    ecb->xs->xs_periph->periph_target);
2001 			if ((ti->flags & T_SYNCHOFF) == 0)
2002 				/* We can re-start sync negotiation */
2003 				ti->flags |= T_NEGOTIATE;
2004 			break;
2005 		case SEND_PARITY_ERROR:
2006 			sc->sc_omess[0] = MSG_PARITY_ERROR;
2007 			break;
2008 		case SEND_ABORT:
2009 			sc->sc_flags |= NCR_ABORTING;
2010 			sc->sc_omess[0] = MSG_ABORT;
2011 			break;
2012 		case SEND_INIT_DET_ERR:
2013 			sc->sc_omess[0] = MSG_INITIATOR_DET_ERR;
2014 			break;
2015 		case SEND_REJECT:
2016 			sc->sc_omess[0] = MSG_MESSAGE_REJECT;
2017 			break;
2018 		default:
2019 			/*
2020 			 * We normally do not get here, since the chip
2021 			 * automatically turns off ATN before the last
2022 			 * byte of a message is sent to the target.
2023 			 * However, if the target rejects our (multi-byte)
2024 			 * message early by switching to MSG IN phase
2025 			 * ATN remains on, so the target may return to
2026 			 * MSG OUT phase. If there are no scheduled messages
2027 			 * left we send a NO-OP.
2028 			 *
2029 			 * XXX - Note that this leaves no useful purpose for
2030 			 * the NCR_ATN flag.
2031 			 */
2032 			sc->sc_flags &= ~NCR_ATN;
2033 			sc->sc_omess[0] = MSG_NOOP;
2034 			break;
2035 		}
2036 		sc->sc_omp = sc->sc_omess;
2037 	}
2038 
2039 #ifdef DEBUG
2040 	if (ncr53c9x_debug & NCR_SHOWMSGS) {
2041 		int i;
2042 
2043 		NCR_MSGS(("<msgout:"));
2044 		for (i = 0; i < sc->sc_omlen; i++)
2045 			NCR_MSGS((" %02x", sc->sc_omess[i]));
2046 		NCR_MSGS(("> "));
2047 	}
2048 #endif
2049 	if (sc->sc_rev == NCR_VARIANT_FAS366) {
2050 		/*
2051 		 * XXX fifo size
2052 		 */
2053 		ncr53c9x_flushfifo(sc);
2054 		ncr53c9x_wrfifo(sc, sc->sc_omp, sc->sc_omlen);
2055 		sc->sc_cmdlen = 0;
2056 		NCRCMD(sc, NCRCMD_TRANS);
2057 	} else {
2058 		/* (re)send the message */
2059 		size = uimin(sc->sc_omlen, sc->sc_maxxfer);
2060 		NCRDMA_SETUP(sc, &sc->sc_omp, &sc->sc_omlen, 0, &size);
2061 		/* Program the SCSI counter */
2062 		NCR_SET_COUNT(sc, size);
2063 
2064 		/* Load the count in and start the message-out transfer */
2065 		NCRCMD(sc, NCRCMD_NOP | NCRCMD_DMA);
2066 		NCRCMD(sc, NCRCMD_TRANS | NCRCMD_DMA);
2067 		NCRDMA_GO(sc);
2068 	}
2069 }
2070 
2071 /*
2072  * This is the most critical part of the driver, and has to know
2073  * how to deal with *all* error conditions and phases from the SCSI
2074  * bus. If there are no errors and the DMA was active, then call the
2075  * DMA pseudo-interrupt handler. If this returns 1, then that was it
2076  * and we can return from here without further processing.
2077  *
2078  * Most of this needs verifying.
2079  */
2080 int
2081 ncr53c9x_intr(void *arg)
2082 {
2083 	struct ncr53c9x_softc *sc = arg;
2084 	struct ncr53c9x_ecb *ecb;
2085 	struct scsipi_periph *periph;
2086 	struct ncr53c9x_tinfo *ti;
2087 	size_t size;
2088 	int nfifo;
2089 
2090 	NCR_INTS(("[ncr53c9x_intr: state %d]", sc->sc_state));
2091 
2092 	if (!NCRDMA_ISINTR(sc))
2093 		return 0;
2094 
2095 	mutex_enter(&sc->sc_lock);
2096 again:
2097 	/* and what do the registers say... */
2098 	ncr53c9x_readregs(sc);
2099 
2100 	sc->sc_intrcnt.ev_count++;
2101 
2102 	/*
2103 	 * At the moment, only a SCSI Bus Reset or Illegal
2104 	 * Command are classed as errors. A disconnect is a
2105 	 * valid condition, and we let the code check is the
2106 	 * "NCR_BUSFREE_OK" flag was set before declaring it
2107 	 * and error.
2108 	 *
2109 	 * Also, the status register tells us about "Gross
2110 	 * Errors" and "Parity errors". Only the Gross Error
2111 	 * is really bad, and the parity errors are dealt
2112 	 * with later
2113 	 *
2114 	 * TODO
2115 	 *	If there are too many parity error, go to slow
2116 	 *	cable mode ?
2117 	 */
2118 
2119 	/* SCSI Reset */
2120 	if ((sc->sc_espintr & NCRINTR_SBR) != 0) {
2121 		if ((NCR_READ_REG(sc, NCR_FFLAG) & NCRFIFO_FF) != 0) {
2122 			NCRCMD(sc, NCRCMD_FLUSH);
2123 			DELAY(1);
2124 		}
2125 		if (sc->sc_state != NCR_SBR) {
2126 			printf("%s: SCSI bus reset\n",
2127 			    device_xname(sc->sc_dev));
2128 			ncr53c9x_init(sc, 0); /* Restart everything */
2129 			goto out;
2130 		}
2131 #if 0
2132 /*XXX*/		printf("<expected bus reset: "
2133 		    "[intr %x, stat %x, step %d]>\n",
2134 		    sc->sc_espintr, sc->sc_espstat, sc->sc_espstep);
2135 #endif
2136 		if (sc->sc_nexus != NULL)
2137 			panic("%s: nexus in reset state",
2138 			    device_xname(sc->sc_dev));
2139 		goto sched;
2140 	}
2141 
2142 	ecb = sc->sc_nexus;
2143 
2144 #define NCRINTR_ERR (NCRINTR_SBR|NCRINTR_ILL)
2145 	if (sc->sc_espintr & NCRINTR_ERR ||
2146 	    sc->sc_espstat & NCRSTAT_GE) {
2147 
2148 		if ((sc->sc_espstat & NCRSTAT_GE) != 0) {
2149 			/* Gross Error; no target ? */
2150 			if (NCR_READ_REG(sc, NCR_FFLAG) & NCRFIFO_FF) {
2151 				NCRCMD(sc, NCRCMD_FLUSH);
2152 				DELAY(1);
2153 			}
2154 			if (sc->sc_state == NCR_CONNECTED ||
2155 			    sc->sc_state == NCR_SELECTING) {
2156 				ecb->xs->error = XS_TIMEOUT;
2157 				ncr53c9x_done(sc, ecb);
2158 			}
2159 			goto out;
2160 		}
2161 
2162 		if ((sc->sc_espintr & NCRINTR_ILL) != 0) {
2163 			if ((sc->sc_flags & NCR_EXPECT_ILLCMD) != 0) {
2164 				/*
2165 				 * Eat away "Illegal command" interrupt
2166 				 * on a ESP100 caused by a re-selection
2167 				 * while we were trying to select
2168 				 * another target.
2169 				 */
2170 #ifdef NCR53C9X_DEBUG
2171 				printf("%s: ESP100 work-around activated\n",
2172 					device_xname(sc->sc_dev));
2173 #endif
2174 				sc->sc_flags &= ~NCR_EXPECT_ILLCMD;
2175 				goto out;
2176 			}
2177 			/* illegal command, out of sync ? */
2178 			printf("%s: illegal command: 0x%x "
2179 			    "(state %d, phase %x, prevphase %x)\n",
2180 			    device_xname(sc->sc_dev), sc->sc_lastcmd,
2181 			    sc->sc_state, sc->sc_phase, sc->sc_prevphase);
2182 			if (NCR_READ_REG(sc, NCR_FFLAG) & NCRFIFO_FF) {
2183 				NCRCMD(sc, NCRCMD_FLUSH);
2184 				DELAY(1);
2185 			}
2186 			ncr53c9x_init(sc, 1); /* Restart everything */
2187 			goto out;
2188 		}
2189 	}
2190 	sc->sc_flags &= ~NCR_EXPECT_ILLCMD;
2191 
2192 	/*
2193 	 * Call if DMA is active.
2194 	 *
2195 	 * If DMA_INTR returns true, then maybe go 'round the loop
2196 	 * again in case there is no more DMA queued, but a phase
2197 	 * change is expected.
2198 	 */
2199 	if (NCRDMA_ISACTIVE(sc)) {
2200 		int r = NCRDMA_INTR(sc);
2201 		if (r == -1) {
2202 			printf("%s: DMA error; resetting\n",
2203 			    device_xname(sc->sc_dev));
2204 			ncr53c9x_init(sc, 1);
2205 			goto out;
2206 		}
2207 		/* If DMA active here, then go back to work... */
2208 		if (NCRDMA_ISACTIVE(sc))
2209 			goto out;
2210 
2211 		if ((sc->sc_espstat & NCRSTAT_TC) == 0) {
2212 			/*
2213 			 * DMA not completed.  If we can not find a
2214 			 * acceptable explanation, print a diagnostic.
2215 			 */
2216 			if (sc->sc_state == NCR_SELECTING)
2217 				/*
2218 				 * This can happen if we are reselected
2219 				 * while using DMA to select a target.
2220 				 */
2221 				/*void*/;
2222 			else if (sc->sc_prevphase == MESSAGE_OUT_PHASE) {
2223 				/*
2224 				 * Our (multi-byte) message (eg SDTR) was
2225 				 * interrupted by the target to send
2226 				 * a MSG REJECT.
2227 				 * Print diagnostic if current phase
2228 				 * is not MESSAGE IN.
2229 				 */
2230 				if (sc->sc_phase != MESSAGE_IN_PHASE)
2231 					printf("%s: !TC on MSG OUT"
2232 					    " [intr %x, stat %x, step %d]"
2233 					    " prevphase %x, resid %lx\n",
2234 					    device_xname(sc->sc_dev),
2235 					    sc->sc_espintr,
2236 					    sc->sc_espstat,
2237 					    sc->sc_espstep,
2238 					    sc->sc_prevphase,
2239 					    (u_long)sc->sc_omlen);
2240 			} else if (sc->sc_dleft == 0) {
2241 				/*
2242 				 * The DMA operation was started for
2243 				 * a DATA transfer. Print a diagnostic
2244 				 * if the DMA counter and TC bit
2245 				 * appear to be out of sync.
2246 				 */
2247 				printf("%s: !TC on DATA XFER"
2248 				    " [intr %x, stat %x, step %d]"
2249 				    " prevphase %x, resid %x\n",
2250 				    device_xname(sc->sc_dev),
2251 				    sc->sc_espintr,
2252 				    sc->sc_espstat,
2253 				    sc->sc_espstep,
2254 				    sc->sc_prevphase,
2255 				    ecb ? ecb->dleft : -1);
2256 			}
2257 		}
2258 	}
2259 
2260 	/*
2261 	 * Check for less serious errors.
2262 	 */
2263 	if ((sc->sc_espstat & NCRSTAT_PE) != 0) {
2264 		printf("%s: SCSI bus parity error\n", device_xname(sc->sc_dev));
2265 		if (sc->sc_prevphase == MESSAGE_IN_PHASE)
2266 			ncr53c9x_sched_msgout(SEND_PARITY_ERROR);
2267 		else
2268 			ncr53c9x_sched_msgout(SEND_INIT_DET_ERR);
2269 	}
2270 
2271 	if ((sc->sc_espintr & NCRINTR_DIS) != 0) {
2272 		sc->sc_msgify = 0;
2273 		NCR_INTS(("<DISC [intr %x, stat %x, step %d]>",
2274 		    sc->sc_espintr,sc->sc_espstat,sc->sc_espstep));
2275 		if (NCR_READ_REG(sc, NCR_FFLAG) & NCRFIFO_FF) {
2276 			NCRCMD(sc, NCRCMD_FLUSH);
2277 #if 0
2278 			DELAY(1);
2279 #endif
2280 		}
2281 		/*
2282 		 * This command must (apparently) be issued within
2283 		 * 250mS of a disconnect. So here you are...
2284 		 */
2285 		NCRCMD(sc, NCRCMD_ENSEL);
2286 
2287 		switch (sc->sc_state) {
2288 		case NCR_RESELECTED:
2289 			goto sched;
2290 
2291 		case NCR_SELECTING:
2292 		{
2293 			struct ncr53c9x_linfo *li;
2294 
2295 			ecb->xs->error = XS_SELTIMEOUT;
2296 
2297 			/* Selection timeout -- discard all LUNs if empty */
2298 			periph = ecb->xs->xs_periph;
2299 			ti = &sc->sc_tinfo[periph->periph_target];
2300 			li = LIST_FIRST(&ti->luns);
2301 			while (li != NULL) {
2302 				if (li->untagged == NULL && li->used == 0) {
2303 					if (li->lun < NCR_NLUN)
2304 						ti->lun[li->lun] = NULL;
2305 					LIST_REMOVE(li, link);
2306 					free(li, M_DEVBUF);
2307 					/*
2308 					 * Restart the search at the beginning
2309 					 */
2310 					li = LIST_FIRST(&ti->luns);
2311 					continue;
2312 				}
2313 				li = LIST_NEXT(li, link);
2314 			}
2315 			goto finish;
2316 		}
2317 		case NCR_CONNECTED:
2318 			if ((sc->sc_flags & NCR_SYNCHNEGO) != 0) {
2319 #ifdef NCR53C9X_DEBUG
2320 				if (ecb != NULL)
2321 					scsipi_printaddr(ecb->xs->xs_periph);
2322 				printf("sync nego not completed!\n");
2323 #endif
2324 				ti = &sc->sc_tinfo[
2325 				    ecb->xs->xs_periph->periph_target];
2326 				sc->sc_flags &= ~NCR_SYNCHNEGO;
2327 				ti->flags &= ~(T_NEGOTIATE | T_SYNCMODE);
2328 			}
2329 
2330 			/* it may be OK to disconnect */
2331 			if ((sc->sc_flags & NCR_ABORTING) == 0) {
2332 				/*
2333 				 * Section 5.1.1 of the SCSI 2 spec
2334 				 * suggests issuing a REQUEST SENSE
2335 				 * following an unexpected disconnect.
2336 				 * Some devices go into a contingent
2337 				 * allegiance condition when
2338 				 * disconnecting, and this is necessary
2339 				 * to clean up their state.
2340 				 */
2341 				printf("%s: unexpected disconnect "
2342 			"[state %d, intr %x, stat %x, phase(c %x, p %x)]; ",
2343 					device_xname(sc->sc_dev), sc->sc_state,
2344 					sc->sc_espintr, sc->sc_espstat,
2345 					sc->sc_phase, sc->sc_prevphase);
2346 
2347 				if ((ecb->flags & ECB_SENSE) != 0) {
2348 					printf("resetting\n");
2349 					goto reset;
2350 				}
2351 				printf("sending REQUEST SENSE\n");
2352 				callout_stop(&ecb->xs->xs_callout);
2353 				ncr53c9x_sense(sc, ecb);
2354 				goto out;
2355 			}
2356 
2357 			ecb->xs->error = XS_TIMEOUT;
2358 			goto finish;
2359 
2360 		case NCR_DISCONNECT:
2361 			sc->sc_nexus = NULL;
2362 			goto sched;
2363 
2364 		case NCR_CMDCOMPLETE:
2365 			goto finish;
2366 		}
2367 	}
2368 
2369 	switch (sc->sc_state) {
2370 
2371 	case NCR_SBR:
2372 		printf("%s: waiting for SCSI Bus Reset to happen\n",
2373 		    device_xname(sc->sc_dev));
2374 		goto out;
2375 
2376 	case NCR_RESELECTED:
2377 		/*
2378 		 * we must be continuing a message ?
2379 		 */
2380 		printf("%s: unhandled reselect continuation, "
2381 		    "state %d, intr %02x\n",
2382 		    device_xname(sc->sc_dev), sc->sc_state, sc->sc_espintr);
2383 		ncr53c9x_init(sc, 1);
2384 		goto out;
2385 
2386 	case NCR_IDENTIFIED:
2387 		ecb = sc->sc_nexus;
2388 		if (sc->sc_phase != MESSAGE_IN_PHASE) {
2389 			int i = (NCR_READ_REG(sc, NCR_FFLAG) & NCRFIFO_FF);
2390 			/*
2391 			 * Things are seriously screwed up.
2392 			 * Pull the brakes, i.e. reset
2393 			 */
2394 			printf("%s: target didn't send tag: %d bytes in fifo\n",
2395 			    device_xname(sc->sc_dev), i);
2396 			/* Drain and display fifo */
2397 			while (i-- > 0)
2398 				printf("[%d] ", NCR_READ_REG(sc, NCR_FIFO));
2399 
2400 			ncr53c9x_init(sc, 1);
2401 			goto out;
2402 		} else
2403 			goto msgin;
2404 
2405 	case NCR_IDLE:
2406 	case NCR_SELECTING:
2407 		ecb = sc->sc_nexus;
2408 		if (sc->sc_espintr & NCRINTR_RESEL) {
2409 			sc->sc_msgpriq = sc->sc_msgout = sc->sc_msgoutq = 0;
2410 			sc->sc_flags = 0;
2411 			/*
2412 			 * If we're trying to select a
2413 			 * target ourselves, push our command
2414 			 * back into the ready list.
2415 			 */
2416 			if (sc->sc_state == NCR_SELECTING) {
2417 				NCR_INTS(("backoff selector "));
2418 				callout_stop(&ecb->xs->xs_callout);
2419 				ncr53c9x_dequeue(sc, ecb);
2420 				TAILQ_INSERT_HEAD(&sc->ready_list, ecb, chain);
2421 				ecb->flags |= ECB_READY;
2422 				ecb = sc->sc_nexus = NULL;
2423 			}
2424 			sc->sc_state = NCR_RESELECTED;
2425 			if (sc->sc_phase != MESSAGE_IN_PHASE) {
2426 				/*
2427 				 * Things are seriously screwed up.
2428 				 * Pull the brakes, i.e. reset
2429 				 */
2430 				printf("%s: target didn't identify\n",
2431 				    device_xname(sc->sc_dev));
2432 				ncr53c9x_init(sc, 1);
2433 				goto out;
2434 			}
2435 			/*
2436 			 * The C90 only inhibits FIFO writes until reselection
2437 			 * is complete, instead of waiting until the interrupt
2438 			 * status register has been read.  So, if the reselect
2439 			 * happens while we were entering command bytes (for
2440 			 * another target) some of those bytes can appear in
2441 			 * the FIFO here, after the interrupt is taken.
2442 			 *
2443 			 * To remedy this situation, pull the Selection ID
2444 			 * and Identify message from the FIFO directly, and
2445 			 * ignore any extraneous fifo contents. Also, set
2446 			 * a flag that allows one Illegal Command Interrupt
2447 			 * to occur which the chip also generates as a result
2448 			 * of writing to the FIFO during a reselect.
2449 			 */
2450 			if (sc->sc_rev == NCR_VARIANT_ESP100) {
2451 				nfifo = NCR_READ_REG(sc, NCR_FFLAG) &
2452 				    NCRFIFO_FF;
2453 				sc->sc_imess[0] = NCR_READ_REG(sc, NCR_FIFO);
2454 				sc->sc_imess[1] = NCR_READ_REG(sc, NCR_FIFO);
2455 				sc->sc_imlen = 2;
2456 				if (nfifo != 2) {
2457 					/* Flush the rest */
2458 					NCRCMD(sc, NCRCMD_FLUSH);
2459 				}
2460 				sc->sc_flags |= NCR_EXPECT_ILLCMD;
2461 				if (nfifo > 2)
2462 					nfifo = 2; /* We fixed it.. */
2463 			} else
2464 				nfifo = ncr53c9x_rdfifo(sc, NCR_RDFIFO_START);
2465 
2466 			if (nfifo != 2) {
2467 				printf("%s: RESELECT: %d bytes in FIFO! "
2468 				    "[intr %x, stat %x, step %d, "
2469 				    "prevphase %x]\n",
2470 				    device_xname(sc->sc_dev),
2471 				    nfifo,
2472 				    sc->sc_espintr,
2473 				    sc->sc_espstat,
2474 				    sc->sc_espstep,
2475 				    sc->sc_prevphase);
2476 				ncr53c9x_init(sc, 1);
2477 				goto out;
2478 			}
2479 			sc->sc_selid = sc->sc_imess[0];
2480 			NCR_INTS(("selid=%02x ", sc->sc_selid));
2481 
2482 			/* Handle identify message */
2483 			ncr53c9x_msgin(sc);
2484 
2485 			if (sc->sc_state != NCR_CONNECTED &&
2486 			    sc->sc_state != NCR_IDENTIFIED) {
2487 				/* IDENTIFY fail?! */
2488 				printf("%s: identify failed, "
2489 				    "state %d, intr %02x\n",
2490 				    device_xname(sc->sc_dev),
2491 				    sc->sc_state, sc->sc_espintr);
2492 				ncr53c9x_init(sc, 1);
2493 				goto out;
2494 			}
2495 			goto shortcut; /* ie. next phase expected soon */
2496 		}
2497 
2498 #define	NCRINTR_DONE	(NCRINTR_FC | NCRINTR_BS)
2499 		if ((sc->sc_espintr & NCRINTR_DONE) == NCRINTR_DONE) {
2500 			/*
2501 			 * Arbitration won; examine the `step' register
2502 			 * to determine how far the selection could progress.
2503 			 */
2504 			ecb = sc->sc_nexus;
2505 			if (ecb == NULL)
2506 				panic("%s: no nexus", __func__);
2507 
2508 			periph = ecb->xs->xs_periph;
2509 			ti = &sc->sc_tinfo[periph->periph_target];
2510 
2511 			switch (sc->sc_espstep) {
2512 			case 0:
2513 				/*
2514 				 * The target did not respond with a
2515 				 * message out phase - probably an old
2516 				 * device that doesn't recognize ATN.
2517 				 * Clear ATN and just continue, the
2518 				 * target should be in the command
2519 				 * phase.
2520 				 * XXXX check for command phase?
2521 				 */
2522 				NCRCMD(sc, NCRCMD_RSTATN);
2523 				break;
2524 			case 1:
2525 				if ((ti->flags & T_NEGOTIATE) == 0 &&
2526 				    ecb->tag[0] == 0) {
2527 					printf("%s: step 1 & !NEG\n",
2528 					    device_xname(sc->sc_dev));
2529 					goto reset;
2530 				}
2531 				if (sc->sc_phase != MESSAGE_OUT_PHASE) {
2532 					printf("%s: !MSGOUT\n",
2533 					    device_xname(sc->sc_dev));
2534 					goto reset;
2535 				}
2536 				if (ti->flags & T_WIDE) {
2537 					ti->flags |= T_WDTRSENT;
2538 					ncr53c9x_sched_msgout(SEND_WDTR);
2539 				}
2540 				if (ti->flags & T_NEGOTIATE) {
2541 					/* Start negotiating */
2542 					ti->period = sc->sc_minsync;
2543 					ti->offset = 15;
2544 					sc->sc_flags |= NCR_SYNCHNEGO;
2545 					if (ecb->tag[0])
2546 						ncr53c9x_sched_msgout(
2547 						    SEND_TAG | SEND_SDTR);
2548 					else
2549 						ncr53c9x_sched_msgout(
2550 						    SEND_SDTR);
2551 				} else {
2552 					/* Could not do ATN3 so send TAG */
2553 					ncr53c9x_sched_msgout(SEND_TAG);
2554 				}
2555 				sc->sc_prevphase = MESSAGE_OUT_PHASE; /* XXXX */
2556 				break;
2557 			case 3:
2558 				/*
2559 				 * Grr, this is supposed to mean
2560 				 * "target left command phase  prematurely".
2561 				 * It seems to happen regularly when
2562 				 * sync mode is on.
2563 				 * Look at FIFO to see if command went out.
2564 				 * (Timing problems?)
2565 				 */
2566 				if (sc->sc_features & NCR_F_DMASELECT) {
2567 					if (sc->sc_cmdlen == 0)
2568 						/* Hope for the best.. */
2569 						break;
2570 				} else if ((NCR_READ_REG(sc, NCR_FFLAG)
2571 				    & NCRFIFO_FF) == 0) {
2572 					/* Hope for the best.. */
2573 					break;
2574 				}
2575 				printf("(%s:%d:%d): selection failed;"
2576 				    " %d left in FIFO "
2577 				    "[intr %x, stat %x, step %d]\n",
2578 				    device_xname(sc->sc_dev),
2579 				    periph->periph_target,
2580 				    periph->periph_lun,
2581 				    NCR_READ_REG(sc, NCR_FFLAG)
2582 				     & NCRFIFO_FF,
2583 				    sc->sc_espintr, sc->sc_espstat,
2584 				    sc->sc_espstep);
2585 				NCRCMD(sc, NCRCMD_FLUSH);
2586 				ncr53c9x_sched_msgout(SEND_ABORT);
2587 				goto out;
2588 			case 2:
2589 				/* Select stuck at Command Phase */
2590 				NCRCMD(sc, NCRCMD_FLUSH);
2591 				break;
2592 			case 4:
2593 				if (sc->sc_features & NCR_F_DMASELECT &&
2594 				    sc->sc_cmdlen != 0)
2595 					printf("(%s:%d:%d): select; "
2596 					    "%lu left in DMA buffer "
2597 					    "[intr %x, stat %x, step %d]\n",
2598 					    device_xname(sc->sc_dev),
2599 					    periph->periph_target,
2600 					    periph->periph_lun,
2601 					    (u_long)sc->sc_cmdlen,
2602 					    sc->sc_espintr,
2603 					    sc->sc_espstat,
2604 					    sc->sc_espstep);
2605 				/* So far, everything went fine */
2606 				break;
2607 			}
2608 
2609 			sc->sc_prevphase = INVALID_PHASE; /* ?? */
2610 			/* Do an implicit RESTORE POINTERS. */
2611 			sc->sc_dp = ecb->daddr;
2612 			sc->sc_dleft = ecb->dleft;
2613 			sc->sc_state = NCR_CONNECTED;
2614 			break;
2615 
2616 		} else {
2617 
2618 			printf("%s: unexpected status after select"
2619 			    ": [intr %x, stat %x, step %x]\n",
2620 			    device_xname(sc->sc_dev),
2621 			    sc->sc_espintr, sc->sc_espstat, sc->sc_espstep);
2622 			NCRCMD(sc, NCRCMD_FLUSH);
2623 			DELAY(1);
2624 			goto reset;
2625 		}
2626 		if (sc->sc_state == NCR_IDLE) {
2627 			printf("%s: stray interrupt\n",
2628 			    device_xname(sc->sc_dev));
2629 			mutex_exit(&sc->sc_lock);
2630 			return 0;
2631 		}
2632 		break;
2633 
2634 	case NCR_CONNECTED:
2635 		if ((sc->sc_flags & NCR_ICCS) != 0) {
2636 			/* "Initiate Command Complete Steps" in progress */
2637 			uint8_t msg;
2638 
2639 			sc->sc_flags &= ~NCR_ICCS;
2640 
2641 			if ((sc->sc_espintr & NCRINTR_DONE) == 0) {
2642 				printf("%s: ICCS: "
2643 				    ": [intr %x, stat %x, step %x]\n",
2644 				    device_xname(sc->sc_dev),
2645 				    sc->sc_espintr, sc->sc_espstat,
2646 				    sc->sc_espstep);
2647 			}
2648 			ncr53c9x_rdfifo(sc, NCR_RDFIFO_START);
2649 			if (sc->sc_imlen < 2)
2650 				printf("%s: can't get status, only %d bytes\n",
2651 				    device_xname(sc->sc_dev),
2652 				    (int)sc->sc_imlen);
2653 			ecb->stat = sc->sc_imess[sc->sc_imlen - 2];
2654 			msg = sc->sc_imess[sc->sc_imlen - 1];
2655 			NCR_PHASE(("<stat:(%x,%x)>", ecb->stat, msg));
2656 			if (msg == MSG_CMDCOMPLETE) {
2657 				ecb->dleft = (ecb->flags & ECB_TENTATIVE_DONE)
2658 				    ? 0 : sc->sc_dleft;
2659 				if ((ecb->flags & ECB_SENSE) == 0)
2660 					ecb->xs->resid = ecb->dleft;
2661 				sc->sc_state = NCR_CMDCOMPLETE;
2662 			} else
2663 				printf("%s: STATUS_PHASE: msg %d\n",
2664 				    device_xname(sc->sc_dev), msg);
2665 			sc->sc_imlen = 0;
2666 			NCRCMD(sc, NCRCMD_MSGOK);
2667 			goto shortcut; /* ie. wait for disconnect */
2668 		}
2669 		break;
2670 
2671 	default:
2672 		printf("%s: invalid state: %d [intr %x, phase(c %x, p %x)]\n",
2673 			device_xname(sc->sc_dev), sc->sc_state,
2674 			sc->sc_espintr, sc->sc_phase, sc->sc_prevphase);
2675 		goto reset;
2676 	}
2677 
2678 	/*
2679 	 * Driver is now in state NCR_CONNECTED, i.e. we
2680 	 * have a current command working the SCSI bus.
2681 	 */
2682 	if (sc->sc_state != NCR_CONNECTED || ecb == NULL) {
2683 		panic("%s: no nexus", __func__);
2684 	}
2685 
2686 	switch (sc->sc_phase) {
2687 	case MESSAGE_OUT_PHASE:
2688 		NCR_PHASE(("MESSAGE_OUT_PHASE "));
2689 		ncr53c9x_msgout(sc);
2690 		sc->sc_prevphase = MESSAGE_OUT_PHASE;
2691 		break;
2692 
2693 	case MESSAGE_IN_PHASE:
2694 msgin:
2695 		NCR_PHASE(("MESSAGE_IN_PHASE "));
2696 		if ((sc->sc_espintr & NCRINTR_BS) != 0) {
2697 			if ((sc->sc_rev != NCR_VARIANT_FAS366) ||
2698 			    (sc->sc_espstat2 & NCRFAS_STAT2_EMPTY) == 0) {
2699 				NCRCMD(sc, NCRCMD_FLUSH);
2700 			}
2701 			sc->sc_flags |= NCR_WAITI;
2702 			NCRCMD(sc, NCRCMD_TRANS);
2703 		} else if ((sc->sc_espintr & NCRINTR_FC) != 0) {
2704 			if ((sc->sc_flags & NCR_WAITI) == 0) {
2705 				printf("%s: MSGIN: unexpected FC bit: "
2706 				    "[intr %x, stat %x, step %x]\n",
2707 				    device_xname(sc->sc_dev),
2708 				    sc->sc_espintr, sc->sc_espstat,
2709 				    sc->sc_espstep);
2710 			}
2711 			sc->sc_flags &= ~NCR_WAITI;
2712 			ncr53c9x_rdfifo(sc,
2713 			    (sc->sc_prevphase == sc->sc_phase) ?
2714 			    NCR_RDFIFO_CONTINUE : NCR_RDFIFO_START);
2715 			ncr53c9x_msgin(sc);
2716 		} else {
2717 			printf("%s: MSGIN: weird bits: "
2718 			    "[intr %x, stat %x, step %x]\n",
2719 			    device_xname(sc->sc_dev),
2720 			    sc->sc_espintr, sc->sc_espstat, sc->sc_espstep);
2721 		}
2722 		sc->sc_prevphase = MESSAGE_IN_PHASE;
2723 		goto shortcut;	/* i.e. expect data to be ready */
2724 
2725 	case COMMAND_PHASE:
2726 		/*
2727 		 * Send the command block. Normally we don't see this
2728 		 * phase because the SEL_ATN command takes care of
2729 		 * all this. However, we end up here if either the
2730 		 * target or we wanted to exchange some more messages
2731 		 * first (e.g. to start negotiations).
2732 		 */
2733 
2734 		NCR_PHASE(("COMMAND_PHASE 0x%02x (%d) ",
2735 		    ecb->cmd.cmd.opcode, ecb->clen));
2736 		if (NCR_READ_REG(sc, NCR_FFLAG) & NCRFIFO_FF) {
2737 			NCRCMD(sc, NCRCMD_FLUSH);
2738 #if 0
2739 			DELAY(1);
2740 #endif
2741 		}
2742 		if (sc->sc_features & NCR_F_DMASELECT) {
2743 			/* setup DMA transfer for command */
2744 			size = ecb->clen;
2745 			sc->sc_cmdlen = size;
2746 			sc->sc_cmdp = (void *)&ecb->cmd.cmd;
2747 			NCRDMA_SETUP(sc, &sc->sc_cmdp, &sc->sc_cmdlen,
2748 			    0, &size);
2749 			/* Program the SCSI counter */
2750 			NCR_SET_COUNT(sc, size);
2751 
2752 			/* load the count in */
2753 			NCRCMD(sc, NCRCMD_NOP | NCRCMD_DMA);
2754 
2755 			/* start the command transfer */
2756 			NCRCMD(sc, NCRCMD_TRANS | NCRCMD_DMA);
2757 			NCRDMA_GO(sc);
2758 		} else {
2759 			ncr53c9x_wrfifo(sc, (uint8_t *)&ecb->cmd.cmd,
2760 			    ecb->clen);
2761 			sc->sc_cmdlen = 0;
2762 			NCRCMD(sc, NCRCMD_TRANS);
2763 		}
2764 		sc->sc_prevphase = COMMAND_PHASE;
2765 		break;
2766 
2767 	case DATA_OUT_PHASE:
2768 		NCR_PHASE(("DATA_OUT_PHASE [%ld] ",(long)sc->sc_dleft));
2769 		NCRCMD(sc, NCRCMD_FLUSH);
2770 		size = uimin(sc->sc_dleft, sc->sc_maxxfer);
2771 		NCRDMA_SETUP(sc, &sc->sc_dp, &sc->sc_dleft, 0, &size);
2772 		sc->sc_prevphase = DATA_OUT_PHASE;
2773 		goto setup_xfer;
2774 
2775 	case DATA_IN_PHASE:
2776 		NCR_PHASE(("DATA_IN_PHASE "));
2777 		if (sc->sc_rev == NCR_VARIANT_ESP100)
2778 			NCRCMD(sc, NCRCMD_FLUSH);
2779 		size = uimin(sc->sc_dleft, sc->sc_maxxfer);
2780 		NCRDMA_SETUP(sc, &sc->sc_dp, &sc->sc_dleft, 1, &size);
2781 		sc->sc_prevphase = DATA_IN_PHASE;
2782 	setup_xfer:
2783 		/* Target returned to data phase: wipe "done" memory */
2784 		ecb->flags &= ~ECB_TENTATIVE_DONE;
2785 
2786 		/* Program the SCSI counter */
2787 		NCR_SET_COUNT(sc, size);
2788 
2789 		/* load the count in */
2790 		NCRCMD(sc, NCRCMD_NOP | NCRCMD_DMA);
2791 
2792 		/*
2793 		 * Note that if `size' is 0, we've already transceived
2794 		 * all the bytes we want but we're still in DATA PHASE.
2795 		 * Apparently, the device needs padding. Also, a
2796 		 * transfer size of 0 means "maximum" to the chip
2797 		 * DMA logic.
2798 		 */
2799 		NCRCMD(sc,
2800 		    (size == 0 ? NCRCMD_TRPAD : NCRCMD_TRANS) | NCRCMD_DMA);
2801 		NCRDMA_GO(sc);
2802 		goto out;
2803 
2804 	case STATUS_PHASE:
2805 		NCR_PHASE(("STATUS_PHASE "));
2806 		sc->sc_flags |= NCR_ICCS;
2807 		NCRCMD(sc, NCRCMD_ICCS);
2808 		sc->sc_prevphase = STATUS_PHASE;
2809 		goto shortcut;	/* i.e. expect status results soon */
2810 
2811 	case INVALID_PHASE:
2812 		break;
2813 
2814 	default:
2815 		printf("%s: unexpected bus phase; resetting\n",
2816 		    device_xname(sc->sc_dev));
2817 		goto reset;
2818 	}
2819 
2820 out:
2821 	mutex_exit(&sc->sc_lock);
2822 	return 1;
2823 
2824 reset:
2825 	ncr53c9x_init(sc, 1);
2826 	goto out;
2827 
2828 finish:
2829 	ncr53c9x_done(sc, ecb);
2830 	goto out;
2831 
2832 sched:
2833 	sc->sc_state = NCR_IDLE;
2834 	ncr53c9x_sched(sc);
2835 	goto out;
2836 
2837 shortcut:
2838 	/*
2839 	 * The idea is that many of the SCSI operations take very little
2840 	 * time, and going away and getting interrupted is too high an
2841 	 * overhead to pay. For example, selecting, sending a message
2842 	 * and command and then doing some work can be done in one "pass".
2843 	 *
2844 	 * The delay is a heuristic. It is 2 when at 20MHz, 2 at 25MHz and 1
2845 	 * at 40MHz. This needs testing.
2846 	 */
2847 	{
2848 		struct timeval wait, cur;
2849 
2850 		microtime(&wait);
2851 		wait.tv_usec += 50 / sc->sc_freq;
2852 		if (wait.tv_usec > 1000000) {
2853 			wait.tv_sec++;
2854 			wait.tv_usec -= 1000000;
2855 		}
2856 		do {
2857 			if (NCRDMA_ISINTR(sc))
2858 				goto again;
2859 			microtime(&cur);
2860 		} while (timercmp(&cur, &wait, <=));
2861 	}
2862 	goto out;
2863 }
2864 
2865 void
2866 ncr53c9x_abort(struct ncr53c9x_softc *sc, struct ncr53c9x_ecb *ecb)
2867 {
2868 
2869 	/* 2 secs for the abort */
2870 	ecb->timeout = NCR_ABORT_TIMEOUT;
2871 	ecb->flags |= ECB_ABORT;
2872 
2873 	if (ecb == sc->sc_nexus) {
2874 		/*
2875 		 * If we're still selecting, the message will be scheduled
2876 		 * after selection is complete.
2877 		 */
2878 		if (sc->sc_state == NCR_CONNECTED)
2879 			ncr53c9x_sched_msgout(SEND_ABORT);
2880 
2881 		/*
2882 		 * Reschedule timeout.
2883 		 */
2884 		callout_reset(&ecb->xs->xs_callout, mstohz(ecb->timeout),
2885 		    ncr53c9x_timeout, ecb);
2886 	} else {
2887 		/*
2888 		 * Just leave the command where it is.
2889 		 * XXX - what choice do we have but to reset the SCSI
2890 		 *	 eventually?
2891 		 */
2892 		if (sc->sc_state == NCR_IDLE)
2893 			ncr53c9x_sched(sc);
2894 	}
2895 }
2896 
2897 void
2898 ncr53c9x_timeout(void *arg)
2899 {
2900 	struct ncr53c9x_ecb *ecb = arg;
2901 	struct scsipi_xfer *xs = ecb->xs;
2902 	struct scsipi_periph *periph = xs->xs_periph;
2903 	struct ncr53c9x_softc *sc;
2904 	struct ncr53c9x_tinfo *ti;
2905 
2906 	sc = device_private(periph->periph_channel->chan_adapter->adapt_dev);
2907 	ti = &sc->sc_tinfo[periph->periph_target];
2908 
2909 	scsipi_printaddr(periph);
2910 	printf("%s: timed out [ecb %p (flags 0x%x, dleft %x, stat %x)], "
2911 	    "<state %d, nexus %p, phase(l %x, c %x, p %x), resid %lx, "
2912 	    "msg(q %x,o %x) %s>",
2913 	    device_xname(sc->sc_dev),
2914 	    ecb, ecb->flags, ecb->dleft, ecb->stat,
2915 	    sc->sc_state, sc->sc_nexus,
2916 	    NCR_READ_REG(sc, NCR_STAT),
2917 	    sc->sc_phase, sc->sc_prevphase,
2918 	    (long)sc->sc_dleft, sc->sc_msgpriq, sc->sc_msgout,
2919 	    NCRDMA_ISACTIVE(sc) ? "DMA active" : "");
2920 #if NCR53C9X_DEBUG > 1
2921 	printf("TRACE: %s.", ecb->trace);
2922 #endif
2923 
2924 	mutex_enter(&sc->sc_lock);
2925 
2926 	if (ecb->flags & ECB_ABORT) {
2927 		/* abort timed out */
2928 		printf(" AGAIN\n");
2929 
2930 		ncr53c9x_init(sc, 1);
2931 	} else {
2932 		/* abort the operation that has timed out */
2933 		printf("\n");
2934 		xs->error = XS_TIMEOUT;
2935 		ncr53c9x_abort(sc, ecb);
2936 
2937 		/* Disable sync mode if stuck in a data phase */
2938 		if (ecb == sc->sc_nexus &&
2939 		    (ti->flags & T_SYNCMODE) != 0 &&
2940 		    (sc->sc_phase & (MSGI | CDI)) == 0) {
2941 			/* XXX ASYNC CALLBACK! */
2942 			scsipi_printaddr(periph);
2943 			printf("sync negotiation disabled\n");
2944 			sc->sc_cfflags |=
2945 			    (1 << ((periph->periph_target & 7) + 8));
2946 			ncr53c9x_update_xfer_mode(sc, periph->periph_target);
2947 		}
2948 	}
2949 
2950 	mutex_exit(&sc->sc_lock);
2951 }
2952 
2953 void
2954 ncr53c9x_watch(void *arg)
2955 {
2956 	struct ncr53c9x_softc *sc = arg;
2957 	struct ncr53c9x_tinfo *ti;
2958 	struct ncr53c9x_linfo *li;
2959 	int t;
2960 	/* Delete any structures that have not been used in 10min. */
2961 	time_t old = time_second - (10 * 60);
2962 
2963 	mutex_enter(&sc->sc_lock);
2964 	for (t = 0; t < sc->sc_ntarg; t++) {
2965 		ti = &sc->sc_tinfo[t];
2966 		li = LIST_FIRST(&ti->luns);
2967 		while (li) {
2968 			if (li->last_used < old &&
2969 			    li->untagged == NULL &&
2970 			    li->used == 0) {
2971 				if (li->lun < NCR_NLUN)
2972 					ti->lun[li->lun] = NULL;
2973 				LIST_REMOVE(li, link);
2974 				free(li, M_DEVBUF);
2975 				/* Restart the search at the beginning */
2976 				li = LIST_FIRST(&ti->luns);
2977 				continue;
2978 			}
2979 			li = LIST_NEXT(li, link);
2980 		}
2981 	}
2982 	mutex_exit(&sc->sc_lock);
2983 	callout_reset(&sc->sc_watchdog, 60 * hz, ncr53c9x_watch, sc);
2984 }
2985