xref: /netbsd-src/sys/arch/amiga/dev/sci.c (revision 76dfffe33547c37f8bdd446e3e4ab0f3c16cea4b)
1 /*	$NetBSD: sci.c,v 1.19 1996/10/13 03:07:31 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1994 Michael L. Hitch
5  * Copyright (c) 1990 The Regents of the University of California.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Van Jacobson of Lawrence Berkeley Laboratory.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed by the University of
22  *	California, Berkeley and its contributors.
23  * 4. Neither the name of the University nor the names of its contributors
24  *    may be used to endorse or promote products derived from this software
25  *    without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37  * SUCH DAMAGE.
38  *
39  *	@(#)scsi.c	7.5 (Berkeley) 5/4/91
40  */
41 
42 /*
43  * AMIGA NCR 5380 scsi adaptor driver
44  */
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/device.h>
49 #include <sys/disklabel.h>
50 #include <sys/dkstat.h>
51 #include <sys/buf.h>
52 #include <scsi/scsi_all.h>
53 #include <scsi/scsiconf.h>
54 #include <vm/vm.h>
55 #include <vm/vm_kern.h>
56 #include <vm/vm_page.h>
57 #include <machine/pmap.h>
58 #include <machine/cpu.h>
59 #include <amiga/amiga/device.h>
60 #include <amiga/amiga/custom.h>
61 #include <amiga/amiga/isr.h>
62 #include <amiga/dev/scireg.h>
63 #include <amiga/dev/scivar.h>
64 
65 /*
66  * SCSI delays
67  * In u-seconds, primarily for state changes on the SPC.
68  */
69 #define	SCI_CMD_WAIT	50000	/* wait per step of 'immediate' cmds */
70 #define	SCI_DATA_WAIT	50000	/* wait per data in/out step */
71 #define	SCI_INIT_WAIT	50000	/* wait per step (both) during init */
72 
73 #define	b_cylin		b_resid
74 
75 int  sciicmd __P((struct sci_softc *, int, void *, int, void *, int,u_char));
76 int  scigo __P((struct sci_softc *, struct scsi_xfer *));
77 int  scigetsense __P((struct sci_softc *, struct scsi_xfer *));
78 int  sciselectbus __P((struct sci_softc *, u_char, u_char));
79 void sciabort __P((struct sci_softc *, char *));
80 void scierror __P((struct sci_softc *, u_char));
81 void scisetdelay __P((int));
82 void sci_scsidone __P((struct sci_softc *, int));
83 void sci_donextcmd __P((struct sci_softc *));
84 int  sci_ixfer_out __P((struct sci_softc *, int, register u_char *, int));
85 void sci_ixfer_in __P((struct sci_softc *, int, register u_char *, int));
86 
87 int sci_cmd_wait = SCI_CMD_WAIT;
88 int sci_data_wait = SCI_DATA_WAIT;
89 int sci_init_wait = SCI_INIT_WAIT;
90 
91 int sci_no_dma = 0;
92 
93 #ifdef DEBUG
94 #define QPRINTF(a) if (sci_debug > 1) printf a
95 int	sci_debug = 0;
96 #else
97 #define QPRINTF(a)
98 #endif
99 
100 /*
101  * default minphys routine for sci based controllers
102  */
103 void
104 sci_minphys(bp)
105 	struct buf *bp;
106 {
107 
108 	/*
109 	 * No max transfer at this level.
110 	 */
111 	minphys(bp);
112 }
113 
114 /*
115  * used by specific sci controller
116  *
117  * it appears that the higher level code does nothing with LUN's
118  * so I will too.  I could plug it in, however so could they
119  * in scsi_scsi_cmd().
120  */
121 int
122 sci_scsicmd(xs)
123 	struct scsi_xfer *xs;
124 {
125 	struct sci_pending *pendp;
126 	struct sci_softc *dev;
127 	struct scsi_link *slp;
128 	int flags, s;
129 
130 	slp = xs->sc_link;
131 	dev = slp->adapter_softc;
132 	flags = xs->flags;
133 
134 	if (flags & SCSI_DATA_UIO)
135 		panic("sci: scsi data uio requested");
136 
137 	if (dev->sc_xs && flags & SCSI_POLL)
138 		panic("sci_scsicmd: busy");
139 
140 	s = splbio();
141 	pendp = &dev->sc_xsstore[slp->target][slp->lun];
142 	if (pendp->xs) {
143 		splx(s);
144 		return(TRY_AGAIN_LATER);
145 	}
146 
147 	if (dev->sc_xs) {
148 		pendp->xs = xs;
149 		TAILQ_INSERT_TAIL(&dev->sc_xslist, pendp, link);
150 		splx(s);
151 		return(SUCCESSFULLY_QUEUED);
152 	}
153 	pendp->xs = NULL;
154 	dev->sc_xs = xs;
155 	splx(s);
156 
157 	/*
158 	 * nothing is pending do it now.
159 	 */
160 	sci_donextcmd(dev);
161 
162 	if (flags & SCSI_POLL)
163 		return(COMPLETE);
164 	return(SUCCESSFULLY_QUEUED);
165 }
166 
167 /*
168  * entered with dev->sc_xs pointing to the next xfer to perform
169  */
170 void
171 sci_donextcmd(dev)
172 	struct sci_softc *dev;
173 {
174 	struct scsi_xfer *xs;
175 	struct scsi_link *slp;
176 	int flags, phase, stat;
177 
178 	xs = dev->sc_xs;
179 	slp = xs->sc_link;
180 	flags = xs->flags;
181 
182 	if (flags & SCSI_DATA_IN)
183 		phase = DATA_IN_PHASE;
184 	else if (flags & SCSI_DATA_OUT)
185 		phase = DATA_OUT_PHASE;
186 	else
187 		phase = STATUS_PHASE;
188 
189 	if (flags & SCSI_RESET)
190 		scireset(dev);
191 
192 	dev->sc_stat[0] = -1;
193 	xs->cmd->bytes[0] |= slp->lun << 5;
194 	if (phase == STATUS_PHASE || flags & SCSI_POLL)
195 		stat = sciicmd(dev, slp->target, xs->cmd, xs->cmdlen,
196 		    xs->data, xs->datalen, phase);
197 	else if (scigo(dev, xs) == 0)
198 		return;
199 	else
200 		stat = dev->sc_stat[0];
201 
202 	sci_scsidone(dev, stat);
203 }
204 
205 void
206 sci_scsidone(dev, stat)
207 	struct sci_softc *dev;
208 	int stat;
209 {
210 	struct sci_pending *pendp;
211 	struct scsi_xfer *xs;
212 	int s, donext;
213 
214 	xs = dev->sc_xs;
215 #ifdef DIAGNOSTIC
216 	if (xs == NULL)
217 		panic("sci_scsidone");
218 #endif
219 	/*
220 	 * is this right?
221 	 */
222 	xs->status = stat;
223 
224 	if (stat == 0)
225 		xs->resid = 0;
226 	else {
227 		switch(stat) {
228 		case SCSI_CHECK:
229 			stat = scigetsense(dev, xs);
230 			if (stat != 0)
231 				goto bad_sense;
232 			xs->error = XS_SENSE;
233 			break;
234 		case SCSI_BUSY:
235 			xs->error = XS_BUSY;
236 			break;
237 		bad_sense:
238 		default:
239 			xs->error = XS_DRIVER_STUFFUP;
240 			QPRINTF(("sci_scsicmd() bad %x\n", stat));
241 			break;
242 		}
243 	}
244 	xs->flags |= ITSDONE;
245 
246 	/*
247 	 * grab next command before scsi_done()
248 	 * this way no single device can hog scsi resources.
249 	 */
250 	s = splbio();
251 	pendp = dev->sc_xslist.tqh_first;
252 	if (pendp == NULL) {
253 		donext = 0;
254 		dev->sc_xs = NULL;
255 	} else {
256 		donext = 1;
257 		TAILQ_REMOVE(&dev->sc_xslist, pendp, link);
258 		dev->sc_xs = pendp->xs;
259 		pendp->xs = NULL;
260 	}
261 	splx(s);
262 	scsi_done(xs);
263 
264 	if (donext)
265 		sci_donextcmd(dev);
266 }
267 
268 int
269 scigetsense(dev, xs)
270 	struct sci_softc *dev;
271 	struct scsi_xfer *xs;
272 {
273 	struct scsi_sense rqs;
274 	struct scsi_link *slp;
275 
276 	slp = xs->sc_link;
277 
278 	rqs.opcode = REQUEST_SENSE;
279 	rqs.byte2 = slp->lun << 5;
280 #ifdef not_yet
281 	rqs.length = xs->req_sense_length ? xs->req_sense_length :
282 	    sizeof(xs->sense);
283 #else
284 	rqs.length = sizeof(xs->sense);
285 #endif
286 
287 	rqs.unused[0] = rqs.unused[1] = rqs.control = 0;
288 
289 	return(sciicmd(dev, slp->target, &rqs, sizeof(rqs), &xs->sense,
290 	    rqs.length, DATA_IN_PHASE));
291 }
292 
293 void
294 sciabort(dev, where)
295 	struct sci_softc *dev;
296 	char *where;
297 {
298 	printf ("%s: abort %s: csr = 0x%02x, bus = 0x%02x\n",
299 	  dev->sc_dev.dv_xname, where, *dev->sci_csr, *dev->sci_bus_csr);
300 
301 	if (dev->sc_flags & SCI_SELECTED) {
302 
303 		/* lets just hope it worked.. */
304 		dev->sc_flags &= ~SCI_SELECTED;
305 		/* XXX */
306 		scireset (dev);
307 	}
308 }
309 
310 /*
311  * XXX Set/reset long delays.
312  *
313  * if delay == 0, reset default delays
314  * if delay < 0,  set both delays to default long initialization values
315  * if delay > 0,  set both delays to this value
316  *
317  * Used when a devices is expected to respond slowly (e.g. during
318  * initialization).
319  */
320 void
321 scisetdelay(del)
322 	int del;
323 {
324 	static int saved_cmd_wait, saved_data_wait;
325 
326 	if (del) {
327 		saved_cmd_wait = sci_cmd_wait;
328 		saved_data_wait = sci_data_wait;
329 		if (del > 0)
330 			sci_cmd_wait = sci_data_wait = del;
331 		else
332 			sci_cmd_wait = sci_data_wait = sci_init_wait;
333 	} else {
334 		sci_cmd_wait = saved_cmd_wait;
335 		sci_data_wait = saved_data_wait;
336 	}
337 }
338 
339 void
340 scireset(dev)
341 	struct sci_softc *dev;
342 {
343 	u_int s;
344 	u_char my_id;
345 
346 	dev->sc_flags &= ~SCI_SELECTED;
347 	if (dev->sc_flags & SCI_ALIVE)
348 		sciabort(dev, "reset");
349 
350 	printf("%s: ", dev->sc_dev.dv_xname);
351 
352 	s = splbio();
353 	/* preserve our ID for now */
354 	my_id = 7;
355 
356 	/*
357 	 * Reset the chip
358 	 */
359 	*dev->sci_icmd = SCI_ICMD_TEST;
360 	*dev->sci_icmd = SCI_ICMD_TEST | SCI_ICMD_RST;
361 	delay (25);
362 	*dev->sci_icmd = 0;
363 
364 	/*
365 	 * Set up various chip parameters
366 	 */
367 	*dev->sci_icmd = 0;
368 	*dev->sci_tcmd = 0;
369 	*dev->sci_sel_enb = 0;
370 
371 	/* anything else was zeroed by reset */
372 
373 	splx (s);
374 
375 	printf("sci id %d\n", my_id);
376 	dev->sc_flags |= SCI_ALIVE;
377 }
378 
379 void
380 scierror(dev, csr)
381 	struct sci_softc *dev;
382 	u_char csr;
383 {
384 	struct scsi_xfer *xs;
385 
386 	xs = dev->sc_xs;
387 
388 #ifdef DIAGNOSTIC
389 	if (xs == NULL)
390 		panic("scierror");
391 #endif
392 	if (xs->flags & SCSI_SILENT)
393 		return;
394 
395 	printf("%s: ", dev->sc_dev.dv_xname);
396 	printf("csr == 0x%02i\n", csr);	/* XXX */
397 }
398 
399 /*
400  * select the bus, return when selected or error.
401  */
402 int
403 sciselectbus(dev, target, our_addr)
404         struct sci_softc *dev;
405 	u_char target, our_addr;
406 {
407 	register int timeo = 2500;
408 
409 	QPRINTF (("sciselectbus %d\n", target));
410 
411 	/* if we're already selected, return */
412 	if (dev->sc_flags & SCI_SELECTED)	/* XXXX */
413 		return 1;
414 
415 	if ((*dev->sci_bus_csr & (SCI_BUS_BSY|SCI_BUS_SEL)) &&
416 	    (*dev->sci_bus_csr & (SCI_BUS_BSY|SCI_BUS_SEL)) &&
417 	    (*dev->sci_bus_csr & (SCI_BUS_BSY|SCI_BUS_SEL)))
418 		return 1;
419 
420 	*dev->sci_tcmd = 0;
421 	*dev->sci_odata = 0x80 + (1 << target);
422 	*dev->sci_icmd = SCI_ICMD_DATA|SCI_ICMD_SEL;
423 	while ((*dev->sci_bus_csr & SCI_BUS_BSY) == 0) {
424 		if (--timeo > 0) {
425 			delay(100);
426 		} else {
427 			break;
428 		}
429 	}
430 	if (timeo) {
431 		*dev->sci_icmd = 0;
432 		dev->sc_flags |= SCI_SELECTED;
433 		return (0);
434 	}
435 	*dev->sci_icmd = 0;
436 	return (1);
437 }
438 
439 int
440 sci_ixfer_out(dev, len, buf, phase)
441 	register struct sci_softc *dev;
442 	int len;
443 	register u_char *buf;
444 	int phase;
445 {
446 	register int wait = sci_data_wait;
447 	u_char csr;
448 
449 	QPRINTF(("sci_ixfer_out {%d} %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
450 	  len, buf[0], buf[1], buf[2], buf[3], buf[4], buf[5],
451 	  buf[6], buf[7], buf[8], buf[9]));
452 
453 	*dev->sci_tcmd = phase;
454 	*dev->sci_icmd = SCI_ICMD_DATA;
455 	for (;len > 0; len--) {
456 		csr = *dev->sci_bus_csr;
457 		while (!(csr & SCI_BUS_REQ)) {
458 			if ((csr & SCI_BUS_BSY) == 0 || --wait < 0) {
459 #ifdef DEBUG
460 				if (sci_debug)
461 					printf("sci_ixfer_out fail: l%d i%x w%d\n",
462 					  len, csr, wait);
463 #endif
464 				return (len);
465 			}
466 			delay(1);
467 			csr = *dev->sci_bus_csr;
468 		}
469 
470 		if (!(*dev->sci_csr & SCI_CSR_PHASE_MATCH))
471 			break;
472 		*dev->sci_odata = *buf;
473 		*dev->sci_icmd = SCI_ICMD_DATA|SCI_ICMD_ACK;
474 		buf++;
475 		while (*dev->sci_bus_csr & SCI_BUS_REQ);
476 		*dev->sci_icmd = SCI_ICMD_DATA;
477 	}
478 
479 	QPRINTF(("sci_ixfer_out done\n"));
480 	return (0);
481 }
482 
483 void
484 sci_ixfer_in(dev, len, buf, phase)
485 	struct sci_softc *dev;
486 	int len;
487 	register u_char *buf;
488 	int phase;
489 {
490 	int wait = sci_data_wait;
491 	u_char csr;
492 	volatile register u_char *sci_bus_csr = dev->sci_bus_csr;
493 	volatile register u_char *sci_data = dev->sci_data;
494 	volatile register u_char *sci_icmd = dev->sci_icmd;
495 #ifdef DEBUG
496 	u_char *obp = buf;
497 #endif
498 
499 	csr = *sci_bus_csr;
500 
501 	QPRINTF(("sci_ixfer_in %d, csr=%02x\n", len, csr));
502 
503 	*dev->sci_tcmd = phase;
504 	*sci_icmd = 0;
505 	for (;len > 0; len--) {
506 		csr = *sci_bus_csr;
507 		while (!(csr & SCI_BUS_REQ)) {
508 			if (!(csr & SCI_BUS_BSY) || --wait < 0) {
509 #ifdef DEBUG
510 				if (sci_debug)
511 					printf("sci_ixfer_in fail: l%d i%x w%d\n",
512 					len, csr, wait);
513 #endif
514 				return;
515 			}
516 
517 			delay(1);
518 			csr = *sci_bus_csr;
519 		}
520 
521 		if (!(*dev->sci_csr & SCI_CSR_PHASE_MATCH))
522 			break;
523 		*buf = *sci_data;
524 		*sci_icmd = SCI_ICMD_ACK;
525 		buf++;
526 		while (*sci_bus_csr & SCI_BUS_REQ);
527 		*sci_icmd = 0;
528 	}
529 
530 	QPRINTF(("sci_ixfer_in {%d} %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
531 	  len, obp[0], obp[1], obp[2], obp[3], obp[4], obp[5],
532 	  obp[6], obp[7], obp[8], obp[9]));
533 }
534 
535 /*
536  * SCSI 'immediate' command:  issue a command to some SCSI device
537  * and get back an 'immediate' response (i.e., do programmed xfer
538  * to get the response data).  'cbuf' is a buffer containing a scsi
539  * command of length clen bytes.  'buf' is a buffer of length 'len'
540  * bytes for data.  The transfer direction is determined by the device
541  * (i.e., by the scsi bus data xfer phase).  If 'len' is zero, the
542  * command must supply no data.  'xferphase' is the bus phase the
543  * caller expects to happen after the command is issued.  It should
544  * be one of DATA_IN_PHASE, DATA_OUT_PHASE or STATUS_PHASE.
545  */
546 int
547 sciicmd(dev, target, cbuf, clen, buf, len, xferphase)
548 	struct sci_softc *dev;
549 	void *cbuf, *buf;
550 	int clen, len;
551 	u_char xferphase;
552 {
553 	u_char phase;
554 	register int wait;
555 
556 	/* select the SCSI bus (it's an error if bus isn't free) */
557 	if (sciselectbus (dev, target, dev->sc_scsi_addr))
558 		return -1;
559 	/*
560 	 * Wait for a phase change (or error) then let the device
561 	 * sequence us through the various SCSI phases.
562 	 */
563 	dev->sc_stat[0] = 0xff;
564 	dev->sc_msg[0] = 0xff;
565 	phase = CMD_PHASE;
566 	while (1) {
567 		wait = sci_cmd_wait;
568 
569 		while ((*dev->sci_bus_csr & (SCI_BUS_REQ|SCI_BUS_BSY)) == SCI_BUS_BSY);
570 
571 		QPRINTF((">CSR:%02x<", *dev->sci_bus_csr));
572 		if ((*dev->sci_bus_csr & SCI_BUS_REQ) == 0) {
573 			return -1;
574 		}
575 		phase = SCI_PHASE(*dev->sci_bus_csr);
576 
577 		switch (phase) {
578 		case CMD_PHASE:
579 			if (sci_ixfer_out (dev, clen, cbuf, phase))
580 				goto abort;
581 			phase = xferphase;
582 			break;
583 
584 		case DATA_IN_PHASE:
585 			if (len <= 0)
586 				goto abort;
587 			wait = sci_data_wait;
588 			sci_ixfer_in (dev, len, buf, phase);
589 			phase = STATUS_PHASE;
590 			break;
591 
592 		case DATA_OUT_PHASE:
593 			if (len <= 0)
594 				goto abort;
595 			wait = sci_data_wait;
596 			if (sci_ixfer_out (dev, len, buf, phase))
597 				goto abort;
598 			phase = STATUS_PHASE;
599 			break;
600 
601 		case MESG_IN_PHASE:
602 			dev->sc_msg[0] = 0xff;
603 			sci_ixfer_in (dev, 1, dev->sc_msg,phase);
604 			dev->sc_flags &= ~SCI_SELECTED;
605 			while (*dev->sci_bus_csr & SCI_BUS_BSY);
606 			goto out;
607 			break;
608 
609 		case MESG_OUT_PHASE:
610 			phase = STATUS_PHASE;
611 			break;
612 
613 		case STATUS_PHASE:
614 			sci_ixfer_in (dev, 1, dev->sc_stat, phase);
615 			phase = MESG_IN_PHASE;
616 			break;
617 
618 		case BUS_FREE_PHASE:
619 			goto out;
620 
621 		default:
622 		printf("sci: unexpected phase %d in icmd from %d\n",
623 		  phase, target);
624 		goto abort;
625 		}
626 #if 0
627 		if (wait <= 0)
628 			goto abort;
629 #endif
630 	}
631 
632 abort:
633 	sciabort(dev, "icmd");
634 out:
635 	QPRINTF(("=STS:%02x=", dev->sc_stat[0]));
636 	return (dev->sc_stat[0]);
637 }
638 
639 int
640 scigo(dev, xs)
641 	struct sci_softc *dev;
642 	struct scsi_xfer *xs;
643 {
644 	int count, target;
645 	u_char phase, *addr;
646 
647 	target = xs->sc_link->target;
648 	count = xs->datalen;
649 	addr = xs->data;
650 
651 	if (sci_no_dma)	{
652 		sciicmd (dev, target, (u_char *) xs->cmd, xs->cmdlen,
653 		  addr, count,
654 		  xs->flags & SCSI_DATA_IN ? DATA_IN_PHASE : DATA_OUT_PHASE);
655 
656 		return (1);
657 	}
658 
659 	/* select the SCSI bus (it's an error if bus isn't free) */
660 	if (sciselectbus (dev, target, dev->sc_scsi_addr))
661 		return -1;
662 	/*
663 	 * Wait for a phase change (or error) then let the device
664 	 * sequence us through the various SCSI phases.
665 	 */
666 	dev->sc_stat[0] = 0xff;
667 	dev->sc_msg[0] = 0xff;
668 	phase = CMD_PHASE;
669 	while (1) {
670 		while ((*dev->sci_bus_csr & (SCI_BUS_REQ|SCI_BUS_BSY)) ==
671 		  SCI_BUS_BSY);
672 
673 		QPRINTF((">CSR:%02x<", *dev->sci_bus_csr));
674 		if ((*dev->sci_bus_csr & SCI_BUS_REQ) == 0) {
675 			goto abort;
676 		}
677 		phase = SCI_PHASE(*dev->sci_bus_csr);
678 
679 		switch (phase) {
680 		case CMD_PHASE:
681 			if (sci_ixfer_out (dev, xs->cmdlen, (u_char *) xs->cmd, phase))
682 				goto abort;
683 			phase = xs->flags & SCSI_DATA_IN ? DATA_IN_PHASE : DATA_OUT_PHASE;
684 			break;
685 
686 		case DATA_IN_PHASE:
687 			if (count <= 0)
688 				goto abort;
689 			/* XXX use psuedo DMA if available */
690 			if (count >= 128 && dev->dma_xfer_in)
691 				(*dev->dma_xfer_in)(dev, count, addr, phase);
692 			else
693 				sci_ixfer_in (dev, count, addr, phase);
694 			phase = STATUS_PHASE;
695 			break;
696 
697 		case DATA_OUT_PHASE:
698 			if (count <= 0)
699 				goto abort;
700 			/* XXX use psuedo DMA if available */
701 			if (count >= 128 && dev->dma_xfer_out)
702 				(*dev->dma_xfer_out)(dev, count, addr, phase);
703 			else
704 				if (sci_ixfer_out (dev, count, addr, phase))
705 					goto abort;
706 			phase = STATUS_PHASE;
707 			break;
708 
709 		case MESG_IN_PHASE:
710 			dev->sc_msg[0] = 0xff;
711 			sci_ixfer_in (dev, 1, dev->sc_msg,phase);
712 			dev->sc_flags &= ~SCI_SELECTED;
713 			while (*dev->sci_bus_csr & SCI_BUS_BSY);
714 			goto out;
715 			break;
716 
717 		case MESG_OUT_PHASE:
718 			phase = STATUS_PHASE;
719 			break;
720 
721 		case STATUS_PHASE:
722 			sci_ixfer_in (dev, 1, dev->sc_stat, phase);
723 			phase = MESG_IN_PHASE;
724 			break;
725 
726 		case BUS_FREE_PHASE:
727 			goto out;
728 
729 		default:
730 		printf("sci: unexpected phase %d in icmd from %d\n",
731 		  phase, target);
732 		goto abort;
733 		}
734 	}
735 
736 abort:
737 	sciabort(dev, "go");
738 out:
739 	QPRINTF(("=STS:%02x=", dev->sc_stat[0]));
740 	return (1);
741 }
742