xref: /original-bsd/sys/hp300/dev/scsi.c (revision b3f911e0)
1 /*
2  * Copyright (c) 1990 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Van Jacobson of Lawrence Berkeley Laboratory.
7  *
8  * %sccs.include.redist.c%
9  *
10  *	@(#)scsi.c	7.1 (Berkeley) 05/08/90
11  */
12 
13 /*
14  * HP9000/3xx 98658 SCSI host adaptor driver.
15  */
16 #include "scsi.h"
17 #if NSCSI > 0
18 
19 #ifndef lint
20 static char rcsid[] = "$Header: scsi.c,v 1.3 90/01/06 04:56:50 van Exp $";
21 #endif
22 
23 #include "param.h"
24 #include "systm.h"
25 #include "buf.h"
26 #include "device.h"
27 #include "scsivar.h"
28 #include "scsireg.h"
29 #include "dmavar.h"
30 
31 #include "machine/cpu.h"
32 #include "machine/isr.h"
33 
34 extern void isrlink();
35 extern void printf();
36 extern void _insque();
37 extern void _remque();
38 extern void bzero();
39 
40 int	scsiinit(), scsigo(), scsiintr(), scsixfer();
41 void	scsistart(), scsidone(), scsifree(), scsireset();
42 struct	driver scsidriver = {
43 	scsiinit, "scsi", (int (*)())scsistart, scsigo, scsiintr,
44 	(int (*)())scsidone,
45 };
46 
47 struct	scsi_softc scsi_softc[NSCSI];
48 struct	isr scsi_isr[NSCSI];
49 
50 int scsi_cmd_wait = 512;	/* microsec wait per step of 'immediate' cmds */
51 int scsi_data_wait = 512;	/* wait per data in/out step */
52 int scsi_nosync = 1;		/* inhibit sync xfers if 1 */
53 
54 #ifdef DEBUG
55 int	scsi_debug = 0;
56 #define WAITHIST
57 #endif
58 
59 #ifdef WAITHIST
60 #define MAXWAIT	2048
61 u_int	ixstart_wait[MAXWAIT+2];
62 u_int	ixin_wait[MAXWAIT+2];
63 u_int	ixout_wait[MAXWAIT+2];
64 u_int	mxin_wait[MAXWAIT+2];
65 u_int	cxin_wait[MAXWAIT+2];
66 u_int	fxfr_wait[MAXWAIT+2];
67 u_int	sgo_wait[MAXWAIT+2];
68 #define HIST(h,w) (++h[((w)>MAXWAIT? MAXWAIT : ((w) < 0 ? -1 : (w))) + 1]);
69 #else
70 #define HIST(h,w)
71 #endif
72 
73 #define	b_cylin		b_resid
74 
75 static void
76 scsiabort(hs, hd, where)
77 	register struct scsi_softc *hs;
78 	volatile register struct scsidevice *hd;
79 	char *where;
80 {
81 	int len;
82 	u_char junk;
83 
84 	printf("scsi%d: abort from %s: phase=0x%x, ssts=0x%x, ints=0x%x\n",
85 		hs->sc_hc->hp_unit, where, hd->scsi_psns, hd->scsi_ssts,
86 		hd->scsi_ints);
87 
88 	hd->scsi_ints = hd->scsi_ints;
89 	hd->scsi_csr = 0;
90 	if (hd->scsi_psns == 0 || (hd->scsi_ssts & SSTS_INITIATOR) == 0)
91 		/* no longer connected to scsi target */
92 		return;
93 
94 	/* get the number of bytes remaining in current xfer + fudge */
95 	len = (hd->scsi_tch << 16) | (hd->scsi_tcm << 8) | hd->scsi_tcl;
96 
97 	/* for that many bus cycles, try to send an abort msg */
98 	for (len += 1024; (hd->scsi_ssts & SSTS_INITIATOR) && --len >= 0; ) {
99 		hd->scsi_scmd = SCMD_SET_ATN;
100 		while ((hd->scsi_psns & PSNS_REQ) == 0) {
101 			if (! (hd->scsi_ssts & SSTS_INITIATOR))
102 				goto out;
103 			DELAY(1);
104 		}
105 		if ((hd->scsi_psns & PHASE) == MESG_OUT_PHASE)
106 			hd->scsi_scmd = SCMD_RST_ATN;
107 		hd->scsi_pctl = hd->scsi_psns & PHASE;
108 		if (hd->scsi_psns & PHASE_IO) {
109 			/* one of the input phases - read & discard a byte */
110 			hd->scsi_scmd = SCMD_SET_ACK;
111 			if (hd->scsi_tmod == 0)
112 				while (hd->scsi_psns & PSNS_REQ)
113 					DELAY(1);
114 			junk = hd->scsi_temp;
115 		} else {
116 			/* one of the output phases - send an abort msg */
117 			hd->scsi_temp = MSG_ABORT;
118 			hd->scsi_scmd = SCMD_SET_ACK;
119 			if (hd->scsi_tmod == 0)
120 				while (hd->scsi_psns & PSNS_REQ)
121 					DELAY(1);
122 		}
123 		hd->scsi_scmd = SCMD_RST_ACK;
124 	}
125 out:
126 	/*
127 	 * Either the abort was successful & the bus is disconnected or
128 	 * the device didn't listen.  If the latter, announce the problem.
129 	 * Either way, reset the card & the SPC.
130 	 */
131 	if (len < 0 && hs)
132 		printf("scsi%d: abort failed.  phase=0x%x, ssts=0x%x\n",
133 			hs->sc_hc->hp_unit, hd->scsi_psns, hd->scsi_ssts);
134 
135 	if (! ((junk = hd->scsi_ints) & INTS_RESEL)) {
136 		hd->scsi_sctl |= SCTL_CTRLRST;
137 		DELAY(1);
138 		hd->scsi_sctl &=~ SCTL_CTRLRST;
139 		hd->scsi_hconf = 0;
140 		hd->scsi_ints = hd->scsi_ints;
141 	}
142 }
143 
144 int
145 scsiinit(hc)
146 	register struct hp_ctlr *hc;
147 {
148 	register struct scsi_softc *hs = &scsi_softc[hc->hp_unit];
149 	register struct scsidevice *hd = (struct scsidevice *)hc->hp_addr;
150 
151 	if ((hd->scsi_id & ID_MASK) != SCSI_ID)
152 		return(0);
153 	hc->hp_ipl = SCSI_IPL(hd->scsi_csr);
154 	hs->sc_hc = hc;
155 	hs->sc_dq.dq_unit = hc->hp_unit;
156 	hs->sc_dq.dq_driver = &scsidriver;
157 	hs->sc_sq.dq_forw = hs->sc_sq.dq_back = &hs->sc_sq;
158 	scsi_isr[hc->hp_unit].isr_intr = scsiintr;
159 	scsi_isr[hc->hp_unit].isr_ipl = hc->hp_ipl;
160 	scsi_isr[hc->hp_unit].isr_arg = hc->hp_unit;
161 	isrlink(&scsi_isr[hc->hp_unit]);
162 	scsireset(hc->hp_unit);
163 	return(1);
164 }
165 
166 void
167 scsireset(unit)
168 	register int unit;
169 {
170 	register struct scsi_softc *hs = &scsi_softc[unit];
171 	volatile register struct scsidevice *hd =
172 				(struct scsidevice *)hs->sc_hc->hp_addr;
173 	u_int i;
174 
175 	if (hs->sc_flags & SCSI_ALIVE)
176 		scsiabort(hs, hd, "reset");
177 
178 	printf("scsi%d: ", unit);
179 
180 	hd->scsi_id = 0xFF;
181 	DELAY(100);
182 	/*
183 	 * Disable interrupts then reset the FUJI chip.
184 	 */
185 	hd->scsi_csr  = 0;
186 	hd->scsi_sctl = SCTL_DISABLE | SCTL_CTRLRST;
187 	hd->scsi_scmd = 0;
188 	hd->scsi_tmod = 0;
189 	hd->scsi_pctl = 0;
190 	hd->scsi_temp = 0;
191 	hd->scsi_tch  = 0;
192 	hd->scsi_tcm  = 0;
193 	hd->scsi_tcl  = 0;
194 	hd->scsi_ints = 0;
195 
196 	if ((hd->scsi_id & ID_WORD_DMA) == 0) {
197 		hs->sc_flags |= SCSI_DMA32;
198 		printf("32 bit dma, ");
199 	}
200 
201 	/* Determine Max Synchronous Transfer Rate */
202 	if (scsi_nosync)
203 		i = 3;
204 	else
205 		i = SCSI_SYNC_XFER(hd->scsi_hconf);
206 	switch (i) {
207 		case 0:
208 			hs->sc_sync = TMOD_SYNC | 0x3e; /* 250 nsecs */
209 			printf("250ns sync");
210 			break;
211 		case 1:
212 			hs->sc_sync = TMOD_SYNC | 0x5e; /* 375 nsecs */
213 			printf("375ns sync");
214 			break;
215 		case 2:
216 			hs->sc_sync = TMOD_SYNC | 0x7d; /* 500 nsecs */
217 			printf("500ns sync");
218 			break;
219 		case 3:
220 			hs->sc_sync = 0;
221 			printf("async");
222 			break;
223 		}
224 
225 	/*
226 	 * Configure the FUJI chip with its SCSI address, all
227 	 * interrupts enabled & appropriate parity.
228 	 */
229 	i = (~hd->scsi_hconf) & 0x7;
230 	hs->sc_scsi_addr = 1 << i;
231 	hd->scsi_bdid = i;
232 	if (hd->scsi_hconf & HCONF_PARITY)
233 		hd->scsi_sctl = SCTL_DISABLE | SCTL_ABRT_ENAB |
234 				SCTL_SEL_ENAB | SCTL_RESEL_ENAB |
235 				SCTL_INTR_ENAB | SCTL_PARITY_ENAB;
236 	else {
237 		hd->scsi_sctl = SCTL_DISABLE | SCTL_ABRT_ENAB |
238 				SCTL_SEL_ENAB | SCTL_RESEL_ENAB |
239 				SCTL_INTR_ENAB;
240 		printf(", no parity");
241 	}
242 	hd->scsi_sctl &=~ SCTL_DISABLE;
243 
244 	printf(", scsi id %d\n", i);
245 	hs->sc_flags |= SCSI_ALIVE;
246 }
247 
248 static void
249 scsierror(hs, hd, ints)
250 	register struct scsi_softc *hs;
251 	volatile register struct scsidevice *hd;
252 	u_char ints;
253 {
254 	int unit = hs->sc_hc->hp_unit;
255 	char *sep = "";
256 
257 	printf("scsi%d: ", unit);
258 	if (ints & INTS_RST) {
259 		DELAY(100);
260 		if (hd->scsi_hconf & HCONF_SD)
261 			printf("spurious RST interrupt");
262 		else
263 			printf("hardware error - check fuse");
264 		sep = ", ";
265 	}
266 	if ((ints & INTS_HARD_ERR) || hd->scsi_serr) {
267 		if (hd->scsi_serr & SERR_SCSI_PAR) {
268 			printf("%sparity err", sep);
269 			sep = ", ";
270 		}
271 		if (hd->scsi_serr & SERR_SPC_PAR) {
272 			printf("%sSPC parity err", sep);
273 			sep = ", ";
274 		}
275 		if (hd->scsi_serr & SERR_TC_PAR) {
276 			printf("%sTC parity err", sep);
277 			sep = ", ";
278 		}
279 		if (hd->scsi_serr & SERR_PHASE_ERR) {
280 			printf("%sphase err", sep);
281 			sep = ", ";
282 		}
283 		if (hd->scsi_serr & SERR_SHORT_XFR) {
284 			printf("%ssync short transfer err", sep);
285 			sep = ", ";
286 		}
287 		if (hd->scsi_serr & SERR_OFFSET) {
288 			printf("%ssync offset error", sep);
289 			sep = ", ";
290 		}
291 	}
292 	if (ints & INTS_TIMEOUT)
293 		printf("%sSPC select timeout error", sep);
294 	if (ints & INTS_SRV_REQ)
295 		printf("%sspurious SRV_REQ interrupt", sep);
296 	if (ints & INTS_CMD_DONE)
297 		printf("%sspurious CMD_DONE interrupt", sep);
298 	if (ints & INTS_DISCON)
299 		printf("%sspurious disconnect interrupt", sep);
300 	if (ints & INTS_RESEL)
301 		printf("%sspurious reselect interrupt", sep);
302 	if (ints & INTS_SEL)
303 		printf("%sspurious select interrupt", sep);
304 	printf("\n");
305 }
306 
307 static int
308 issue_select(hd, target, our_addr)
309 	volatile register struct scsidevice *hd;
310 	u_char target, our_addr;
311 {
312 	if (hd->scsi_ssts & (SSTS_INITIATOR|SSTS_TARGET|SSTS_BUSY))
313 		return (1);
314 
315 	if (hd->scsi_ints & INTS_DISCON)
316 		hd->scsi_ints = INTS_DISCON;
317 
318 	hd->scsi_pctl = 0;
319 	hd->scsi_temp = (1 << target) | our_addr;
320 	/* select timeout is hardcoded to 2ms */
321 	hd->scsi_tch = 0;
322 	hd->scsi_tcm = 32;
323 	hd->scsi_tcl = 4;
324 
325 	hd->scsi_scmd = SCMD_SELECT;
326 	return (0);
327 }
328 
329 static int
330 wait_for_select(hd)
331 	volatile register struct scsidevice *hd;
332 {
333 	u_char ints;
334 
335 	while ((ints = hd->scsi_ints) == 0)
336 		DELAY(1);
337 	hd->scsi_ints = ints;
338 	return (!(hd->scsi_ssts & SSTS_INITIATOR));
339 }
340 
341 static int
342 ixfer_start(hd, len, phase, wait)
343 	volatile register struct scsidevice *hd;
344 	int len;
345 	u_char phase;
346 	register int wait;
347 {
348 
349 	hd->scsi_tch = len >> 16;
350 	hd->scsi_tcm = len >> 8;
351 	hd->scsi_tcl = len;
352 	hd->scsi_pctl = phase;
353 	hd->scsi_tmod = 0; /*XXX*/
354 	hd->scsi_scmd = SCMD_XFR | SCMD_PROG_XFR;
355 
356 	/* wait for xfer to start or svc_req interrupt */
357 	while ((hd->scsi_ssts & SSTS_BUSY) == 0) {
358 		if (hd->scsi_ints || --wait < 0) {
359 #ifdef DEBUG
360 			if (scsi_debug)
361 				printf("ixfer_start fail: i%x, w%d\n",
362 				       hd->scsi_ints, wait);
363 #endif
364 			HIST(ixstart_wait, wait)
365 			return (0);
366 		}
367 		DELAY(1);
368 	}
369 	HIST(ixstart_wait, wait)
370 	return (1);
371 }
372 
373 static int
374 ixfer_out(hd, len, buf)
375 	volatile register struct scsidevice *hd;
376 	int len;
377 	register u_char *buf;
378 {
379 	register int wait = scsi_data_wait;
380 
381 	for (; len > 0; --len) {
382 		while (hd->scsi_ssts & SSTS_DREG_FULL) {
383 			if (hd->scsi_ints || --wait < 0) {
384 #ifdef DEBUG
385 				if (scsi_debug)
386 					printf("ixfer_out fail: l%d i%x w%d\n",
387 					       len, hd->scsi_ints, wait);
388 #endif
389 				HIST(ixout_wait, wait)
390 				return (len);
391 			}
392 			DELAY(1);
393 		}
394 		hd->scsi_dreg = *buf++;
395 	}
396 	HIST(ixout_wait, wait)
397 	return (0);
398 }
399 
400 static void
401 ixfer_in(hd, len, buf)
402 	volatile register struct scsidevice *hd;
403 	int len;
404 	register u_char *buf;
405 {
406 	register int wait = scsi_data_wait;
407 
408 	for (; len > 0; --len) {
409 		while (hd->scsi_ssts & SSTS_DREG_EMPTY) {
410 			if (hd->scsi_ints || --wait < 0) {
411 				while (! (hd->scsi_ssts & SSTS_DREG_EMPTY)) {
412 					*buf++ = hd->scsi_dreg;
413 					--len;
414 				}
415 #ifdef DEBUG
416 				if (scsi_debug)
417 					printf("ixfer_in fail: l%d i%x w%d\n",
418 					       len, hd->scsi_ints, wait);
419 #endif
420 				HIST(ixin_wait, wait)
421 				return;
422 			}
423 			DELAY(1);
424 		}
425 		*buf++ = hd->scsi_dreg;
426 	}
427 	HIST(ixin_wait, wait)
428 }
429 
430 static int
431 mxfer_in(hd, len, buf, phase)
432 	volatile register struct scsidevice *hd;
433 	register int len;
434 	register u_char *buf;
435 	register u_char phase;
436 {
437 	register int wait = scsi_cmd_wait;
438 	register int i;
439 
440 	hd->scsi_tmod = 0;
441 	for (i = 0; i < len; ++i) {
442 		/*
443 		 * wait for the request line (which says the target
444 		 * wants to give us data).  If the phase changes while
445 		 * we're waiting, we're done.
446 		 */
447 		while ((hd->scsi_psns & PSNS_REQ) == 0) {
448 			if (--wait < 0) {
449 				HIST(mxin_wait, wait)
450 				return (-1);
451 			}
452 			if ((hd->scsi_psns & PHASE) != phase ||
453 			    (hd->scsi_ssts & SSTS_INITIATOR) == 0)
454 				goto out;
455 
456 			DELAY(1);
457 		}
458 		/*
459 		 * set ack (which says we're ready for the data, wait for
460 		 * req to go away (target says data is available), grab the
461 		 * data, then reset ack (say we've got the data).
462 		 */
463 		hd->scsi_pctl = phase;
464 		hd->scsi_scmd = SCMD_SET_ACK;
465 		while (hd->scsi_psns & PSNS_REQ) {
466 			if (--wait < 0) {
467 				HIST(mxin_wait, wait)
468 				return (-2);
469 			}
470 			DELAY(1);
471 		}
472 		*buf++ = hd->scsi_temp;
473 		hd->scsi_scmd = SCMD_RST_ACK;
474 		if (hd->scsi_psns & PSNS_ATN)
475 			hd->scsi_scmd = SCMD_RST_ATN;
476 	}
477 out:
478 	HIST(mxin_wait, wait)
479 	return (i);
480 }
481 
482 /*
483  * SCSI 'immediate' command:  issue a command to some SCSI device
484  * and get back an 'immediate' response (i.e., do programmed xfer
485  * to get the response data).  'cbuf' is a buffer containing a scsi
486  * command of length clen bytes.  'buf' is a buffer of length 'len'
487  * bytes for data.  The transfer direction is determined by the device
488  * (i.e., by the scsi bus data xfer phase).  If 'len' is zero, the
489  * command must supply no data.  'xferphase' is the bus phase the
490  * caller expects to happen after the command is issued.  It should
491  * be one of DATA_IN_PHASE, DATA_OUT_PHASE or STATUS_PHASE.
492  */
493 static int
494 scsiicmd(hs, target, cbuf, clen, buf, len, xferphase)
495 	struct scsi_softc *hs;
496 	int target;
497 	u_char *cbuf;
498 	int clen;
499 	u_char *buf;
500 	int len;
501 	u_char xferphase;
502 {
503 	volatile register struct scsidevice *hd =
504 				(struct scsidevice *)hs->sc_hc->hp_addr;
505 	u_char phase, ints;
506 	register int wait;
507 
508 	/* select the SCSI bus (it's an error if bus isn't free) */
509 	if (issue_select(hd, target, hs->sc_scsi_addr))
510 		return (-1);
511 	if (wait_for_select(hd))
512 		return (-1);
513 	/*
514 	 * Wait for a phase change (or error) then let the device
515 	 * sequence us through the various SCSI phases.
516 	 */
517 	hs->sc_stat[0] = 0xff;
518 	hs->sc_msg[0] = 0xff;
519 	phase = CMD_PHASE;
520 	while (1) {
521 		wait = scsi_cmd_wait;
522 		switch (phase) {
523 
524 		case CMD_PHASE:
525 			if (ixfer_start(hd, clen, phase, wait))
526 				if (ixfer_out(hd, clen, cbuf))
527 					goto abort;
528 			phase = xferphase;
529 			break;
530 
531 		case DATA_IN_PHASE:
532 			if (len <= 0)
533 				goto abort;
534 			wait = scsi_data_wait;
535 			if (ixfer_start(hd, len, phase, wait) ||
536 			    !(hd->scsi_ssts & SSTS_DREG_EMPTY))
537 				ixfer_in(hd, len, buf);
538 			phase = STATUS_PHASE;
539 			break;
540 
541 		case DATA_OUT_PHASE:
542 			if (len <= 0)
543 				goto abort;
544 			wait = scsi_data_wait;
545 			if (ixfer_start(hd, len, phase, wait)) {
546 				if (ixfer_out(hd, len, buf))
547 					goto abort;
548 			}
549 			phase = STATUS_PHASE;
550 			break;
551 
552 		case STATUS_PHASE:
553 			wait = scsi_data_wait;
554 			if (ixfer_start(hd, sizeof(hs->sc_stat), phase, wait) ||
555 			    !(hd->scsi_ssts & SSTS_DREG_EMPTY))
556 				ixfer_in(hd, sizeof(hs->sc_stat), hs->sc_stat);
557 			phase = MESG_IN_PHASE;
558 			break;
559 
560 		case MESG_IN_PHASE:
561 			if (ixfer_start(hd, sizeof(hs->sc_msg), phase, wait) ||
562 			    !(hd->scsi_ssts & SSTS_DREG_EMPTY)) {
563 				ixfer_in(hd, sizeof(hs->sc_msg), hs->sc_msg);
564 				hd->scsi_scmd = SCMD_RST_ACK;
565 			}
566 			phase = BUS_FREE_PHASE;
567 			break;
568 
569 		case BUS_FREE_PHASE:
570 			goto out;
571 
572 		default:
573 			printf("scsi%d: unexpected phase %d in icmd from %d\n",
574 				hs->sc_hc->hp_unit, phase, target);
575 			goto abort;
576 		}
577 		/* wait for last command to complete */
578 		while ((ints = hd->scsi_ints) == 0) {
579 			if (--wait < 0) {
580 				HIST(cxin_wait, wait)
581 				goto abort;
582 			}
583 			DELAY(1);
584 		}
585 		HIST(cxin_wait, wait)
586 		hd->scsi_ints = ints;
587 		if (ints & INTS_SRV_REQ)
588 			phase = hd->scsi_psns & PHASE;
589 		else if (ints & INTS_DISCON)
590 			goto out;
591 		else if ((ints & INTS_CMD_DONE) == 0) {
592 			scsierror(hs, hd, ints);
593 			goto abort;
594 		}
595 	}
596 abort:
597 	scsiabort(hs, hd, "icmd");
598 out:
599 	return (hs->sc_stat[0]);
600 }
601 
602 /*
603  * Finish SCSI xfer command:  After the completion interrupt from
604  * a read/write operation, sequence through the final phases in
605  * programmed i/o.  This routine is a lot like scsiicmd except we
606  * skip (and don't allow) the select, cmd out and data in/out phases.
607  */
608 static void
609 finishxfer(hs, hd, target)
610 	struct scsi_softc *hs;
611 	volatile register struct scsidevice *hd;
612 	int target;
613 {
614 	u_char phase, ints;
615 
616 	/*
617 	 * We specified padding xfer so we ended with either a phase
618 	 * change interrupt (normal case) or an error interrupt (handled
619 	 * elsewhere).  Reset the board dma logic then try to get the
620 	 * completion status & command done msg.  The reset confuses
621 	 * the SPC REQ/ACK logic so we have to do any status/msg input
622 	 * operations via 'manual xfer'.
623 	 */
624 	if (hd->scsi_ssts & SSTS_BUSY) {
625 		int wait = scsi_cmd_wait;
626 
627 		/* wait for dma operation to finish */
628 		while (hd->scsi_ssts & SSTS_BUSY) {
629 			if (--wait < 0) {
630 #ifdef DEBUG
631 				if (scsi_debug)
632 					printf("finishxfer fail: ssts %x\n",
633 					       hd->scsi_ssts);
634 #endif
635 				HIST(fxfr_wait, wait)
636 				goto abort;
637 			}
638 		}
639 		HIST(fxfr_wait, wait)
640 	}
641 	hd->scsi_scmd |= SCMD_PROG_XFR;
642 	hd->scsi_sctl |= SCTL_CTRLRST;
643 	DELAY(1);
644 	hd->scsi_sctl &=~ SCTL_CTRLRST;
645 	hd->scsi_hconf = 0;
646 	hs->sc_stat[0] = 0xff;
647 	hs->sc_msg[0] = 0xff;
648 	hd->scsi_csr = 0;
649 	hd->scsi_ints = ints = hd->scsi_ints;
650 	while (1) {
651 		phase = hd->scsi_psns & PHASE;
652 		switch (phase) {
653 
654 		case STATUS_PHASE:
655 			if (mxfer_in(hd, sizeof(hs->sc_stat), hs->sc_stat,
656 				     phase) <= 0)
657 				goto abort;
658 			break;
659 
660 		case MESG_IN_PHASE:
661 			if (mxfer_in(hd, sizeof(hs->sc_msg), hs->sc_msg,
662 				     phase) < 0)
663 				goto abort;
664 			break;
665 
666 		case BUS_FREE_PHASE:
667 			return;
668 
669 		default:
670 			printf("scsi%d: unexpected phase %d in finishxfer from %d\n",
671 				hs->sc_hc->hp_unit, phase, target);
672 			goto abort;
673 		}
674 		if (ints = hd->scsi_ints) {
675 			hd->scsi_ints = ints;
676 			if (ints & INTS_DISCON)
677 				return;
678 			else if (ints & ~(INTS_SRV_REQ|INTS_CMD_DONE)) {
679 				scsierror(hs, hd, ints);
680 				break;
681 			}
682 		}
683 		if ((hd->scsi_ssts & SSTS_INITIATOR) == 0)
684 			return;
685 	}
686 abort:
687 	scsiabort(hs, hd, "finishxfer");
688 	hs->sc_stat[0] = 0xfe;
689 }
690 
691 int
692 scsi_test_unit_rdy(ctlr, slave, unit)
693 	int ctlr, slave, unit;
694 {
695 	register struct scsi_softc *hs = &scsi_softc[ctlr];
696 	static struct scsi_cdb6 cdb = { CMD_TEST_UNIT_READY };
697 
698 	cdb.lun = unit;
699 	return (scsiicmd(hs, slave, &cdb, sizeof(cdb), (u_char *)0, 0,
700 			 STATUS_PHASE));
701 }
702 
703 int
704 scsi_request_sense(ctlr, slave, unit, buf, len)
705 	int ctlr, slave, unit;
706 	u_char *buf;
707 	unsigned len;
708 {
709 	register struct scsi_softc *hs = &scsi_softc[ctlr];
710 	static struct scsi_cdb6 cdb = { CMD_REQUEST_SENSE };
711 
712 	cdb.lun = unit;
713 	cdb.len = len;
714 	return (scsiicmd(hs, slave, &cdb, sizeof(cdb), buf, len, DATA_IN_PHASE));
715 }
716 
717 int
718 scsi_immed_command(ctlr, slave, unit, cdb, buf, len, rd)
719 	int ctlr, slave, unit;
720 	struct scsi_fmt_cdb *cdb;
721 	u_char *buf;
722 	unsigned len;
723 {
724 	register struct scsi_softc *hs = &scsi_softc[ctlr];
725 
726 	cdb->cdb[1] |= unit << 5;
727 	return (scsiicmd(hs, slave, cdb->cdb, cdb->len, buf, len,
728 			 rd != 0? DATA_IN_PHASE : DATA_OUT_PHASE));
729 }
730 
731 /*
732  * The following routines are test-and-transfer i/o versions of read/write
733  * for things like reading disk labels and writing core dumps.  The
734  * routine scsigo should be used for normal data transfers, NOT these
735  * routines.
736  */
737 int
738 scsi_tt_read(ctlr, slave, unit, buf, len, blk, bshift)
739 	int ctlr, slave, unit;
740 	u_char *buf;
741 	u_int len;
742 	daddr_t blk;
743 	int bshift;
744 {
745 	register struct scsi_softc *hs = &scsi_softc[ctlr];
746 	struct scsi_cdb10 cdb;
747 	int stat;
748 	int old_wait = scsi_data_wait;
749 
750 	scsi_data_wait = 300000;
751 	bzero(&cdb, sizeof(cdb));
752 	cdb.cmd = CMD_READ_EXT;
753 	cdb.lun = unit;
754 	blk >>= bshift;
755 	cdb.lbah = blk >> 24;
756 	cdb.lbahm = blk >> 16;
757 	cdb.lbalm = blk >> 8;
758 	cdb.lbal = blk;
759 	cdb.lenh = len >> (8 + DEV_BSHIFT + bshift);
760 	cdb.lenl = len >> (DEV_BSHIFT + bshift);
761 	stat = scsiicmd(hs, slave, &cdb, sizeof(cdb), buf, len, DATA_IN_PHASE);
762 	scsi_data_wait = old_wait;
763 	return (stat);
764 }
765 
766 int
767 scsi_tt_write(ctlr, slave, unit, buf, len, blk, bshift)
768 	int ctlr, slave, unit;
769 	u_char *buf;
770 	u_int len;
771 	daddr_t blk;
772 	int bshift;
773 {
774 	register struct scsi_softc *hs = &scsi_softc[ctlr];
775 	struct scsi_cdb10 cdb;
776 	int stat;
777 	int old_wait = scsi_data_wait;
778 
779 	scsi_data_wait = 300000;
780 
781 	bzero(&cdb, sizeof(cdb));
782 	cdb.cmd = CMD_WRITE_EXT;
783 	cdb.lun = unit;
784 	blk >>= bshift;
785 	cdb.lbah = blk >> 24;
786 	cdb.lbahm = blk >> 16;
787 	cdb.lbalm = blk >> 8;
788 	cdb.lbal = blk;
789 	cdb.lenh = len >> (8 + DEV_BSHIFT + bshift);
790 	cdb.lenl = len >> (DEV_BSHIFT + bshift);
791 	stat = scsiicmd(hs, slave, &cdb, sizeof(cdb), buf, len, DATA_OUT_PHASE);
792 	scsi_data_wait = old_wait;
793 	return (stat);
794 }
795 
796 
797 int
798 scsireq(dq)
799 	register struct devqueue *dq;
800 {
801 	register struct devqueue *hq;
802 
803 	hq = &scsi_softc[dq->dq_ctlr].sc_sq;
804 	insque(dq, hq->dq_back);
805 	if (dq->dq_back == hq)
806 		return(1);
807 	return(0);
808 }
809 
810 int
811 scsiustart(unit)
812 	int unit;
813 {
814 	register struct scsi_softc *hs = &scsi_softc[unit];
815 
816 	hs->sc_dq.dq_ctlr = DMA0 | DMA1;
817 	if (dmareq(&hs->sc_dq))
818 		return(1);
819 	return(0);
820 }
821 
822 void
823 scsistart(unit)
824 	int unit;
825 {
826 	register struct devqueue *dq;
827 
828 	dq = scsi_softc[unit].sc_sq.dq_forw;
829 	(dq->dq_driver->d_go)(dq->dq_unit);
830 }
831 
832 int
833 scsigo(ctlr, slave, unit, bp, cdb, pad)
834 	int ctlr, slave, unit;
835 	struct buf *bp;
836 	struct scsi_fmt_cdb *cdb;
837 	int pad;
838 {
839 	register struct scsi_softc *hs = &scsi_softc[ctlr];
840 	volatile register struct scsidevice *hd =
841 				(struct scsidevice *)hs->sc_hc->hp_addr;
842 	int i, dmaflags;
843 	u_char phase, ints, cmd;
844 
845 	cdb->cdb[1] |= unit << 5;
846 
847 	/* select the SCSI bus (it's an error if bus isn't free) */
848 	if (issue_select(hd, slave, hs->sc_scsi_addr) || wait_for_select(hd)) {
849 		dmafree(&hs->sc_dq);
850 		return (1);
851 	}
852 	/*
853 	 * Wait for a phase change (or error) then let the device
854 	 * sequence us through command phase (we may have to take
855 	 * a msg in/out before doing the command).  If the disk has
856 	 * to do a seek, it may be a long time until we get a change
857 	 * to data phase so, in the absense of an explicit phase
858 	 * change, we assume data phase will be coming up and tell
859 	 * the SPC to start a transfer whenever it does.  We'll get
860 	 * a service required interrupt later if this assumption is
861 	 * wrong.  Otherwise we'll get a service required int when
862 	 * the transfer changes to status phase.
863 	 */
864 	phase = CMD_PHASE;
865 	while (1) {
866 		register int wait = scsi_cmd_wait;
867 
868 		switch (phase) {
869 
870 		case CMD_PHASE:
871 			if (ixfer_start(hd, cdb->len, phase, wait))
872 				if (ixfer_out(hd, cdb->len, cdb->cdb))
873 					goto abort;
874 			break;
875 
876 		case MESG_IN_PHASE:
877 			if (ixfer_start(hd, sizeof(hs->sc_msg), phase, wait)||
878 			    !(hd->scsi_ssts & SSTS_DREG_EMPTY)) {
879 				ixfer_in(hd, sizeof(hs->sc_msg), hs->sc_msg);
880 				hd->scsi_scmd = SCMD_RST_ACK;
881 			}
882 			phase = BUS_FREE_PHASE;
883 			break;
884 
885 		case DATA_IN_PHASE:
886 		case DATA_OUT_PHASE:
887 			goto out;
888 
889 		default:
890 			printf("scsi%d: unexpected phase %d in go from %d\n",
891 				hs->sc_hc->hp_unit, phase, slave);
892 			goto abort;
893 		}
894 		while ((ints = hd->scsi_ints) == 0) {
895 			if (--wait < 0) {
896 				HIST(sgo_wait, wait)
897 				goto abort;
898 			}
899 			DELAY(1);
900 		}
901 		HIST(sgo_wait, wait)
902 		hd->scsi_ints = ints;
903 		if (ints & INTS_SRV_REQ)
904 			phase = hd->scsi_psns & PHASE;
905 		else if (ints & INTS_CMD_DONE)
906 			goto out;
907 		else {
908 			scsierror(hs, hd, ints);
909 			goto abort;
910 		}
911 	}
912 out:
913 	/*
914 	 * Reset the card dma logic, setup the dma channel then
915 	 * get the dio part of the card set for a dma xfer.
916 	 */
917 	hd->scsi_hconf = 0;
918 	cmd = CSR_IE | (CSR_DE0 << hs->sc_dq.dq_ctlr);
919 	dmaflags = DMAGO_NOINT;
920 	if (bp->b_flags & B_READ)
921 		dmaflags |= DMAGO_READ;
922 	if ((hs->sc_flags & SCSI_DMA32) &&
923 	    ((int)bp->b_un.b_addr & 3) == 0 && (bp->b_bcount & 3) == 0) {
924 		cmd |= CSR_DMA32;
925 		dmaflags |= DMAGO_LWORD;
926 	} else
927 		dmaflags |= DMAGO_WORD;
928 	dmago(hs->sc_dq.dq_ctlr, bp->b_un.b_addr, bp->b_bcount, dmaflags);
929 
930 	if (bp->b_flags & B_READ) {
931 		cmd |= CSR_DMAIN;
932 		phase = DATA_IN_PHASE;
933 	} else
934 		phase = DATA_OUT_PHASE;
935 	hd->scsi_csr = cmd;
936 	/*
937 	 * Setup the SPC for the transfer.  We don't want to take
938 	 * first a command complete then a service required interrupt
939 	 * at the end of the transfer so we try to disable the cmd
940 	 * complete by setting the transfer counter to more bytes
941 	 * than we expect.  (XXX - This strategy may have to be
942 	 * modified to deal with devices that return variable length
943 	 * blocks, e.g., some tape drives.)
944 	 */
945 	cmd = SCMD_XFR;
946 	i = (unsigned)bp->b_bcount;
947 	if (pad) {
948 		cmd |= SCMD_PAD;
949 		/*
950 		 * XXX - If we don't do this, the last 2 or 4 bytes
951 		 * (depending on word/lword DMA) of a read get trashed.
952 		 * It looks like it is necessary for the DMA to complete
953 		 * before the SPC goes into "pad mode"???  Note: if we
954 		 * also do this on a write, the request never completes.
955 		 */
956 		if (bp->b_flags & B_READ)
957 			i += 2;
958 #ifdef DEBUG
959 		hs->sc_flags |= SCSI_PAD;
960 		if (i & 1)
961 			printf("scsi%d: odd byte count: %d bytes @ %d\n",
962 				ctlr, i, bp->b_cylin);
963 #endif
964 	} else
965 		i += 4;
966 	hd->scsi_tch = i >> 16;
967 	hd->scsi_tcm = i >> 8;
968 	hd->scsi_tcl = i;
969 	hd->scsi_pctl = phase;
970 	hd->scsi_tmod = 0;
971 	hd->scsi_scmd = cmd;
972 	hs->sc_flags |= SCSI_IO;
973 	return (0);
974 abort:
975 	scsiabort(hs, hd, "go");
976 	dmafree(&hs->sc_dq);
977 	return (1);
978 }
979 
980 void
981 scsidone(unit)
982 	register int unit;
983 {
984 	volatile register struct scsidevice *hd =
985 			(struct scsidevice *)scsi_softc[unit].sc_hc->hp_addr;
986 
987 	/* dma operation is done -- turn off card dma */
988 	hd->scsi_csr &=~ (CSR_DE1|CSR_DE0);
989 }
990 
991 int
992 scsiintr(unit)
993 	register int unit;
994 {
995 	register struct scsi_softc *hs = &scsi_softc[unit];
996 	volatile register struct scsidevice *hd =
997 				(struct scsidevice *)hs->sc_hc->hp_addr;
998 	register u_char ints;
999 	register struct devqueue *dq;
1000 
1001 	if ((hd->scsi_csr & (CSR_IE|CSR_IR)) != (CSR_IE|CSR_IR))
1002 		return (0);
1003 
1004 	ints = hd->scsi_ints;
1005 	if ((ints & INTS_SRV_REQ) && (hs->sc_flags & SCSI_IO)) {
1006 		/*
1007 		 * this should be the normal i/o completion case.
1008 		 * get the status & cmd complete msg then let the
1009 		 * device driver look at what happened.
1010 		 */
1011 #ifdef DEBUG
1012 		int len = (hd->scsi_tch << 16) | (hd->scsi_tcm << 8) |
1013 			  hd->scsi_tcl;
1014 		if (!(hs->sc_flags & SCSI_PAD))
1015 			len -= 4;
1016 		if (len)
1017 			printf("scsi%d: transfer length error %d\n", unit, len);
1018 		hs->sc_flags &=~ SCSI_PAD;
1019 #endif
1020 		dq = hs->sc_sq.dq_forw;
1021 		finishxfer(hs, hd, dq->dq_unit);
1022 		hs->sc_flags &=~ SCSI_IO;
1023 		dmafree(&hs->sc_dq);
1024 		(dq->dq_driver->d_intr)(dq->dq_unit, hs->sc_stat[0]);
1025 	} else {
1026 		/* Something unexpected happened -- deal with it. */
1027 		hd->scsi_ints = ints;
1028 		hd->scsi_csr = 0;
1029 		scsierror(hs, hd, ints);
1030 		scsiabort(hs, hd, "intr");
1031 		if (hs->sc_flags & SCSI_IO) {
1032 			hs->sc_flags &=~ SCSI_IO;
1033 			dmafree(&hs->sc_dq);
1034 			dq = hs->sc_sq.dq_forw;
1035 			(dq->dq_driver->d_intr)(dq->dq_unit, -1);
1036 		}
1037 	}
1038 	return(1);
1039 }
1040 
1041 void
1042 scsifree(dq)
1043 	register struct devqueue *dq;
1044 {
1045 	register struct devqueue *hq;
1046 
1047 	hq = &scsi_softc[dq->dq_ctlr].sc_sq;
1048 	remque(dq);
1049 	if ((dq = hq->dq_forw) != hq)
1050 		(dq->dq_driver->d_start)(dq->dq_unit);
1051 }
1052 #endif
1053