xref: /netbsd-src/sys/arch/amiga/dev/sci.c (revision d9158b13b5dfe46201430699a3f7a235ecf28df3)
1 /*
2  * Copyright (c) 1994 Michael L. Hitch
3  * Copyright (c) 1990 The Regents of the University of California.
4  * All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * Van Jacobson of Lawrence Berkeley Laboratory.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed by the University of
20  *	California, Berkeley and its contributors.
21  * 4. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  *
37  *	@(#)scsi.c	7.5 (Berkeley) 5/4/91
38  *	$Id: sci.c,v 1.6 1994/06/13 08:13:05 chopps Exp $
39  */
40 
41 /*
42  * AMIGA NCR 5380 scsi adaptor driver
43  */
44 
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/device.h>
48 #include <sys/buf.h>
49 #include <scsi/scsi_all.h>
50 #include <scsi/scsiconf.h>
51 #include <vm/vm.h>
52 #include <vm/vm_kern.h>
53 #include <vm/vm_page.h>
54 #include <machine/pmap.h>
55 #include <machine/cpu.h>
56 #include <amiga/amiga/device.h>
57 #include <amiga/amiga/custom.h>
58 #include <amiga/dev/scireg.h>
59 #include <amiga/dev/scivar.h>
60 
61 /*
62  * SCSI delays
63  * In u-seconds, primarily for state changes on the SPC.
64  */
65 #define	SCI_CMD_WAIT	50000	/* wait per step of 'immediate' cmds */
66 #define	SCI_DATA_WAIT	50000	/* wait per data in/out step */
67 #define	SCI_INIT_WAIT	50000	/* wait per step (both) during init */
68 
69 #define	b_cylin		b_resid
70 
71 int  sciicmd __P((struct sci_softc *, int, void *, int, void *, int,u_char));
72 int  scigo __P((struct sci_softc *, struct scsi_xfer *));
73 int  scigetsense __P((struct sci_softc *, struct scsi_xfer *));
74 int  sciselectbus __P((struct sci_softc *, u_char, u_char));
75 void sciabort __P((struct sci_softc *, char *));
76 void scierror __P((struct sci_softc *, u_char));
77 void scireset __P((struct sci_softc *));
78 void scisetdelay __P((int));
79 void sci_scsidone __P((struct sci_softc *, int));
80 void sci_donextcmd __P((struct sci_softc *));
81 
82 int sci_cmd_wait = SCI_CMD_WAIT;
83 int sci_data_wait = SCI_DATA_WAIT;
84 int sci_init_wait = SCI_INIT_WAIT;
85 
86 int sci_no_dma = 0;
87 
88 #ifdef DEBUG
89 #define QPRINTF(a) if (sci_debug > 1) printf a
90 int	sci_debug = 0;
91 #else
92 #define QPRINTF
93 #endif
94 
95 /*
96  * default minphys routine for sci based controllers
97  */
98 void
99 sci_minphys(bp)
100 	struct buf *bp;
101 {
102 	/*
103 	 * no max transfer at this level
104 	 */
105 }
106 
107 /*
108  * must be used
109  */
110 u_int
111 sci_adinfo()
112 {
113 	/*
114 	 * one request at a time please
115 	 */
116 	return(1);
117 }
118 
119 /*
120  * used by specific sci controller
121  *
122  * it appears that the higher level code does nothing with LUN's
123  * so I will too.  I could plug it in, however so could they
124  * in scsi_scsi_cmd().
125  */
126 int
127 sci_scsicmd(xs)
128 	struct scsi_xfer *xs;
129 {
130 	struct sci_pending *pendp;
131 	struct sci_softc *dev;
132 	struct scsi_link *slp;
133 	int flags, s;
134 
135 	slp = xs->sc_link;
136 	dev = slp->adapter_softc;
137 	flags = xs->flags;
138 
139 	if (flags & SCSI_DATA_UIO)
140 		panic("sci: scsi data uio requested");
141 
142 	if (dev->sc_xs && flags & SCSI_NOMASK)
143 		panic("sci_scsicmd: busy");
144 
145 	s = splbio();
146 	pendp = &dev->sc_xsstore[slp->target][slp->lun];
147 	if (pendp->xs) {
148 		splx(s);
149 		return(TRY_AGAIN_LATER);
150 	}
151 
152 	if (dev->sc_xs) {
153 		pendp->xs = xs;
154 		TAILQ_INSERT_TAIL(&dev->sc_xslist, pendp, link);
155 		splx(s);
156 		return(SUCCESSFULLY_QUEUED);
157 	}
158 	pendp->xs = NULL;
159 	dev->sc_xs = xs;
160 	splx(s);
161 
162 	/*
163 	 * nothing is pending do it now.
164 	 */
165 	sci_donextcmd(dev);
166 
167 	if (flags & SCSI_NOMASK)
168 		return(COMPLETE);
169 	return(SUCCESSFULLY_QUEUED);
170 }
171 
172 /*
173  * entered with dev->sc_xs pointing to the next xfer to perform
174  */
175 void
176 sci_donextcmd(dev)
177 	struct sci_softc *dev;
178 {
179 	struct scsi_xfer *xs;
180 	struct scsi_link *slp;
181 	int flags, phase, stat;
182 
183 	xs = dev->sc_xs;
184 	slp = xs->sc_link;
185 	flags = xs->flags;
186 
187 	if (flags & SCSI_DATA_IN)
188 		phase = DATA_IN_PHASE;
189 	else if (flags & SCSI_DATA_OUT)
190 		phase = DATA_OUT_PHASE;
191 	else
192 		phase = STATUS_PHASE;
193 
194 	if (flags & SCSI_RESET)
195 		scireset(dev);
196 
197 	dev->sc_stat[0] = -1;
198 	if (phase == STATUS_PHASE || flags & SCSI_NOMASK)
199 		stat = sciicmd(dev, slp->target, xs->cmd, xs->cmdlen,
200 		    xs->data, xs->datalen, phase);
201 	else if (scigo(dev, xs) == 0)
202 		return;
203 	else
204 		stat = dev->sc_stat[0];
205 
206 	sci_scsidone(dev, stat);
207 }
208 
209 void
210 sci_scsidone(dev, stat)
211 	struct sci_softc *dev;
212 	int stat;
213 {
214 	struct sci_pending *pendp;
215 	struct scsi_xfer *xs;
216 	int s, donext;
217 
218 	xs = dev->sc_xs;
219 #ifdef DIAGNOSTIC
220 	if (xs == NULL)
221 		panic("sci_scsidone");
222 #endif
223 	/*
224 	 * is this right?
225 	 */
226 	xs->status = stat;
227 
228 	if (stat == 0 || xs->flags & SCSI_ERR_OK)
229 		xs->resid = 0;
230 	else {
231 		switch(stat) {
232 		case SCSI_CHECK:
233 			if (stat = scigetsense(dev, xs))
234 				goto bad_sense;
235 			xs->error = XS_SENSE;
236 			break;
237 		case SCSI_BUSY:
238 			xs->error = XS_BUSY;
239 			break;
240 		bad_sense:
241 		default:
242 			xs->error = XS_DRIVER_STUFFUP;
243 			QPRINTF(("sci_scsicmd() bad %x\n", stat));
244 			break;
245 		}
246 	}
247 	xs->flags |= ITSDONE;
248 
249 	/*
250 	 * grab next command before scsi_done()
251 	 * this way no single device can hog scsi resources.
252 	 */
253 	s = splbio();
254 	pendp = dev->sc_xslist.tqh_first;
255 	if (pendp == NULL) {
256 		donext = 0;
257 		dev->sc_xs = NULL;
258 	} else {
259 		donext = 1;
260 		TAILQ_REMOVE(&dev->sc_xslist, pendp, link);
261 		dev->sc_xs = pendp->xs;
262 		pendp->xs = NULL;
263 	}
264 	splx(s);
265 	scsi_done(xs);
266 
267 	if (donext)
268 		sci_donextcmd(dev);
269 }
270 
271 int
272 scigetsense(dev, xs)
273 	struct sci_softc *dev;
274 	struct scsi_xfer *xs;
275 {
276 	struct scsi_sense rqs;
277 	struct scsi_link *slp;
278 	int stat;
279 
280 	slp = xs->sc_link;
281 
282 	rqs.op_code = REQUEST_SENSE;
283 	rqs.byte2 = slp->lun << 5;
284 #ifdef not_yet
285 	rqs.length = xs->req_sense_length ? xs->req_sense_length :
286 	    sizeof(xs->sense);
287 #else
288 	rqs.length = sizeof(xs->sense);
289 #endif
290 
291 	rqs.unused[0] = rqs.unused[1] = rqs.control = 0;
292 
293 	return(sciicmd(dev, slp->target, &rqs, sizeof(rqs), &xs->sense,
294 	    rqs.length, DATA_IN_PHASE));
295 }
296 
297 void
298 sciabort(dev, where)
299 	struct sci_softc *dev;
300 	char *where;
301 {
302 	printf ("%s: abort %s: csr = 0x%02x, bus = 0x%02x\n",
303 	  dev->sc_dev.dv_xname, where, *dev->sci_csr, *dev->sci_bus_csr);
304 
305 	if (dev->sc_flags & SCI_SELECTED) {
306 
307 		/* XXX */
308 		scireset (dev);
309 		/* lets just hope it worked.. */
310 		dev->sc_flags &= ~SCI_SELECTED;
311 	}
312 }
313 
314 /*
315  * XXX Set/reset long delays.
316  *
317  * if delay == 0, reset default delays
318  * if delay < 0,  set both delays to default long initialization values
319  * if delay > 0,  set both delays to this value
320  *
321  * Used when a devices is expected to respond slowly (e.g. during
322  * initialization).
323  */
324 void
325 scisetdelay(del)
326 	int del;
327 {
328 	static int saved_cmd_wait, saved_data_wait;
329 
330 	if (del) {
331 		saved_cmd_wait = sci_cmd_wait;
332 		saved_data_wait = sci_data_wait;
333 		if (del > 0)
334 			sci_cmd_wait = sci_data_wait = del;
335 		else
336 			sci_cmd_wait = sci_data_wait = sci_init_wait;
337 	} else {
338 		sci_cmd_wait = saved_cmd_wait;
339 		sci_data_wait = saved_data_wait;
340 	}
341 }
342 
343 void
344 scireset(dev)
345 	struct sci_softc *dev;
346 {
347 	u_int i, s;
348 	u_char my_id, csr;
349 
350 	if (dev->sc_flags & SCI_ALIVE)
351 		sciabort(dev, "reset");
352 
353 	printf("%s: ", dev->sc_dev.dv_xname);
354 
355 	s = splbio();
356 	/* preserve our ID for now */
357 	my_id = 7;
358 
359 	/*
360 	 * Reset the chip
361 	 */
362 	*dev->sci_icmd = SCI_ICMD_TEST;
363 	*dev->sci_icmd = SCI_ICMD_TEST | SCI_ICMD_RST;
364 	delay (25);
365 	*dev->sci_icmd = 0;
366 
367 	/*
368 	 * Set up various chip parameters
369 	 */
370 	*dev->sci_icmd = 0;
371 	*dev->sci_tcmd = 0;
372 	*dev->sci_sel_enb = 0;
373 
374 	/* anything else was zeroed by reset */
375 
376 	splx (s);
377 
378 	printf("sci id %d\n", my_id);
379 	dev->sc_flags |= SCI_ALIVE;
380 	dev->sc_flags &= ~SCI_SELECTED;
381 }
382 
383 void
384 scierror(dev, csr)
385 	struct sci_softc *dev;
386 	u_char csr;
387 {
388 	struct scsi_xfer *xs;
389 
390 	xs = dev->sc_xs;
391 
392 #ifdef DIAGNOSTIC
393 	if (xs == NULL)
394 		panic("scierror");
395 #endif
396 	if (xs->flags & SCSI_SILENT)
397 		return;
398 
399 	printf("%s: ", dev->sc_dev.dv_xname);
400 	printf("csr == 0x%02i\n", csr);	/* XXX */
401 }
402 
403 /*
404  * select the bus, return when selected or error.
405  */
406 int
407 sciselectbus(dev, target, our_addr)
408         struct sci_softc *dev;
409 	u_char target, our_addr;
410 {
411 	register int timeo = 2500;
412 
413 	QPRINTF (("sciselectbus %d\n", target));
414 
415 	/* if we're already selected, return */
416 	if (dev->sc_flags & SCI_SELECTED)	/* XXXX */
417 		return 1;
418 
419 	if ((*dev->sci_bus_csr & (SCI_BUS_BSY|SCI_BUS_SEL)) &&
420 	    (*dev->sci_bus_csr & (SCI_BUS_BSY|SCI_BUS_SEL)) &&
421 	    (*dev->sci_bus_csr & (SCI_BUS_BSY|SCI_BUS_SEL)))
422 		return 1;
423 
424 	*dev->sci_tcmd = 0;
425 	*dev->sci_odata = 0x80 + (1 << target);
426 	*dev->sci_icmd = SCI_ICMD_DATA|SCI_ICMD_SEL;
427 	while ((*dev->sci_bus_csr & SCI_BUS_BSY) == 0) {
428 		if (--timeo > 0) {
429 			delay(100);
430 		} else {
431 			break;
432 		}
433 	}
434 	if (timeo) {
435 		*dev->sci_icmd = 0;
436 		dev->sc_flags |= SCI_SELECTED;
437 		return (0);
438 	}
439 	*dev->sci_icmd = 0;
440 	return (1);
441 }
442 
443 int
444 sci_ixfer_out(dev, len, buf, phase)
445 	register struct sci_softc *dev;
446 	int len;
447 	register u_char *buf;
448 	int phase;
449 {
450 	register int wait = sci_data_wait;
451 	u_char csr;
452 
453 	QPRINTF(("sci_ixfer_out {%d} %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
454 	  len, buf[0], buf[1], buf[2], buf[3], buf[4], buf[5],
455 	  buf[6], buf[7], buf[8], buf[9]));
456 
457 	*dev->sci_tcmd = phase;
458 	*dev->sci_icmd = SCI_ICMD_DATA;
459 	for (;len > 0; len--) {
460 		csr = *dev->sci_bus_csr;
461 		while (!(csr & SCI_BUS_REQ)) {
462 			if ((csr & SCI_BUS_BSY) == 0 || --wait < 0) {
463 #ifdef DEBUG
464 				if (sci_debug)
465 					printf("sci_ixfer_out fail: l%d i%x w%d\n",
466 					  len, csr, wait);
467 #endif
468 				return (len);
469 			}
470 			delay(1);
471 			csr = *dev->sci_bus_csr;
472 		}
473 
474 		if (!(*dev->sci_csr & SCI_CSR_PHASE_MATCH))
475 			break;
476 		*dev->sci_odata = *buf;
477 		*dev->sci_icmd = SCI_ICMD_DATA|SCI_ICMD_ACK;
478 		buf++;
479 		while (*dev->sci_bus_csr & SCI_BUS_REQ);
480 		*dev->sci_icmd = SCI_ICMD_DATA;
481 	}
482 
483 	QPRINTF(("sci_ixfer_out done\n"));
484 	return (0);
485 }
486 
487 void
488 sci_ixfer_in(dev, len, buf, phase)
489 	struct sci_softc *dev;
490 	int len;
491 	register u_char *buf;
492 	int phase;
493 {
494 	int wait = sci_data_wait;
495 	u_char *obp = buf;
496 	u_char csr;
497 	volatile register u_char *sci_bus_csr = dev->sci_bus_csr;
498 	volatile register u_char *sci_data = dev->sci_data;
499 	volatile register u_char *sci_icmd = dev->sci_icmd;
500 
501 	csr = *sci_bus_csr;
502 
503 	QPRINTF(("sci_ixfer_in %d, csr=%02x\n", len, csr));
504 
505 	*dev->sci_tcmd = phase;
506 	*sci_icmd = 0;
507 	for (;len > 0; len--) {
508 		csr = *sci_bus_csr;
509 		while (!(csr & SCI_BUS_REQ)) {
510 			if (!(csr & SCI_BUS_BSY) || --wait < 0) {
511 #ifdef DEBUG
512 				if (sci_debug)
513 					printf("sci_ixfer_in fail: l%d i%x w%d\n",
514 					len, csr, wait);
515 #endif
516 				return;
517 			}
518 
519 			delay(1);
520 			csr = *sci_bus_csr;
521 		}
522 
523 		if (!(*dev->sci_csr & SCI_CSR_PHASE_MATCH))
524 			break;
525 		*buf = *sci_data;
526 		*sci_icmd = SCI_ICMD_ACK;
527 		buf++;
528 		while (*sci_bus_csr & SCI_BUS_REQ);
529 		*sci_icmd = 0;
530 	}
531 
532 	QPRINTF(("sci_ixfer_in {%d} %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
533 	  len, obp[0], obp[1], obp[2], obp[3], obp[4], obp[5],
534 	  obp[6], obp[7], obp[8], obp[9]));
535 }
536 
537 /*
538  * SCSI 'immediate' command:  issue a command to some SCSI device
539  * and get back an 'immediate' response (i.e., do programmed xfer
540  * to get the response data).  'cbuf' is a buffer containing a scsi
541  * command of length clen bytes.  'buf' is a buffer of length 'len'
542  * bytes for data.  The transfer direction is determined by the device
543  * (i.e., by the scsi bus data xfer phase).  If 'len' is zero, the
544  * command must supply no data.  'xferphase' is the bus phase the
545  * caller expects to happen after the command is issued.  It should
546  * be one of DATA_IN_PHASE, DATA_OUT_PHASE or STATUS_PHASE.
547  */
548 int
549 sciicmd(dev, target, cbuf, clen, buf, len, xferphase)
550 	struct sci_softc *dev;
551 	void *cbuf, *buf;
552 	int clen, len;
553 	u_char xferphase;
554 {
555 	u_char phase, csr, asr;
556 	register int wait;
557 
558 	/* select the SCSI bus (it's an error if bus isn't free) */
559 	if (sciselectbus (dev, target, dev->sc_scsi_addr))
560 		return -1;
561 	/*
562 	 * Wait for a phase change (or error) then let the device
563 	 * sequence us through the various SCSI phases.
564 	 */
565 	dev->sc_stat[0] = 0xff;
566 	dev->sc_msg[0] = 0xff;
567 	phase = CMD_PHASE;
568 	while (1) {
569 		wait = sci_cmd_wait;
570 
571 		while ((*dev->sci_bus_csr & (SCI_BUS_REQ|SCI_BUS_BSY)) == SCI_BUS_BSY);
572 
573 		QPRINTF((">CSR:%02x<", *dev->sci_bus_csr));
574 		if ((*dev->sci_bus_csr & SCI_BUS_REQ) == 0) {
575 			return -1;
576 		}
577 		phase = SCI_PHASE(*dev->sci_bus_csr);
578 
579 		switch (phase) {
580 		case CMD_PHASE:
581 			if (sci_ixfer_out (dev, clen, cbuf, phase))
582 				goto abort;
583 			phase = xferphase;
584 			break;
585 
586 		case DATA_IN_PHASE:
587 			if (len <= 0)
588 				goto abort;
589 			wait = sci_data_wait;
590 			sci_ixfer_in (dev, len, buf, phase);
591 			phase = STATUS_PHASE;
592 			break;
593 
594 		case DATA_OUT_PHASE:
595 			if (len <= 0)
596 				goto abort;
597 			wait = sci_data_wait;
598 			if (sci_ixfer_out (dev, len, buf, phase))
599 				goto abort;
600 			phase = STATUS_PHASE;
601 			break;
602 
603 		case MESG_IN_PHASE:
604 			dev->sc_msg[0] = 0xff;
605 			sci_ixfer_in (dev, 1, dev->sc_msg,phase);
606 			dev->sc_flags &= ~SCI_SELECTED;
607 			while (*dev->sci_bus_csr & SCI_BUS_BSY);
608 			goto out;
609 			break;
610 
611 		case MESG_OUT_PHASE:
612 			phase = STATUS_PHASE;
613 			break;
614 
615 		case STATUS_PHASE:
616 			sci_ixfer_in (dev, 1, dev->sc_stat, phase);
617 			phase = MESG_IN_PHASE;
618 			break;
619 
620 		case BUS_FREE_PHASE:
621 			goto out;
622 
623 		default:
624 		printf("sci: unexpected phase %d in icmd from %d\n",
625 		  phase, target);
626 		goto abort;
627 		}
628 #if 0
629 		if (wait <= 0)
630 			goto abort;
631 #endif
632 	}
633 
634 abort:
635 	sciabort(dev, "icmd");
636 out:
637 	QPRINTF(("=STS:%02x=", dev->sc_stat[0]));
638 	return (dev->sc_stat[0]);
639 }
640 
641 int
642 scigo(dev, xs)
643 	struct sci_softc *dev;
644 	struct scsi_xfer *xs;
645 {
646 	int i, count, target;
647 	u_char phase, csr, asr, cmd, *addr;
648 	int wait;
649 
650 	target = xs->sc_link->target;
651 	count = xs->datalen;
652 	addr = xs->data;
653 
654 	if (sci_no_dma)	{
655 		sciicmd (dev, target, (u_char *) xs->cmd, xs->cmdlen,
656 		  addr, count,
657 		  xs->flags & SCSI_DATA_IN ? DATA_IN_PHASE : DATA_OUT_PHASE);
658 
659 		return (1);
660 	}
661 
662 	/* select the SCSI bus (it's an error if bus isn't free) */
663 	if (sciselectbus (dev, target, dev->sc_scsi_addr))
664 		return -1;
665 	/*
666 	 * Wait for a phase change (or error) then let the device
667 	 * sequence us through the various SCSI phases.
668 	 */
669 	dev->sc_stat[0] = 0xff;
670 	dev->sc_msg[0] = 0xff;
671 	phase = CMD_PHASE;
672 	while (1) {
673 		while ((*dev->sci_bus_csr & (SCI_BUS_REQ|SCI_BUS_BSY)) ==
674 		  SCI_BUS_BSY);
675 
676 		QPRINTF((">CSR:%02x<", *dev->sci_bus_csr));
677 		if ((*dev->sci_bus_csr & SCI_BUS_REQ) == 0) {
678 			goto abort;
679 		}
680 		phase = SCI_PHASE(*dev->sci_bus_csr);
681 
682 		switch (phase) {
683 		case CMD_PHASE:
684 			if (sci_ixfer_out (dev, xs->cmdlen, xs->cmd, phase))
685 				goto abort;
686 			phase = xs->flags & SCSI_DATA_IN ? DATA_IN_PHASE : DATA_OUT_PHASE;
687 			break;
688 
689 		case DATA_IN_PHASE:
690 			if (count <= 0)
691 				goto abort;
692 			/* XXX use psuedo DMA if available */
693 			if (count >= 128 && dev->dma_xfer_in)
694 				(*dev->dma_xfer_in)(dev, count, addr, phase);
695 			else
696 				sci_ixfer_in (dev, count, addr, phase);
697 			phase = STATUS_PHASE;
698 			break;
699 
700 		case DATA_OUT_PHASE:
701 			if (count <= 0)
702 				goto abort;
703 			/* XXX use psuedo DMA if available */
704 			if (count >= 128 && dev->dma_xfer_out)
705 				(*dev->dma_xfer_out)(dev, count, addr, phase);
706 			else
707 				if (sci_ixfer_out (dev, count, addr, phase))
708 					goto abort;
709 			phase = STATUS_PHASE;
710 			break;
711 
712 		case MESG_IN_PHASE:
713 			dev->sc_msg[0] = 0xff;
714 			sci_ixfer_in (dev, 1, dev->sc_msg,phase);
715 			dev->sc_flags &= ~SCI_SELECTED;
716 			while (*dev->sci_bus_csr & SCI_BUS_BSY);
717 			goto out;
718 			break;
719 
720 		case MESG_OUT_PHASE:
721 			phase = STATUS_PHASE;
722 			break;
723 
724 		case STATUS_PHASE:
725 			sci_ixfer_in (dev, 1, dev->sc_stat, phase);
726 			phase = MESG_IN_PHASE;
727 			break;
728 
729 		case BUS_FREE_PHASE:
730 			goto out;
731 
732 		default:
733 		printf("sci: unexpected phase %d in icmd from %d\n",
734 		  phase, target);
735 		goto abort;
736 		}
737 	}
738 
739 abort:
740 	sciabort(dev, "go");
741 out:
742 	QPRINTF(("=STS:%02x=", dev->sc_stat[0]));
743 	return (1);
744 }
745