xref: /netbsd-src/sys/arch/amiga/dev/sci.c (revision 5bbd2a12505d72a8177929a37b5cee489d0a1cfd)
1 /*	$NetBSD: sci.c,v 1.34 2010/12/20 00:25:26 matt Exp $ */
2 
3 /*
4  * Copyright (c) 1990 The Regents of the University of California.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Van Jacobson of Lawrence Berkeley Laboratory.
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  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	@(#)scsi.c	7.5 (Berkeley) 5/4/91
35  */
36 
37 /*
38  * Copyright (c) 1994 Michael L. Hitch
39  *
40  * This code is derived from software contributed to Berkeley by
41  * Van Jacobson of Lawrence Berkeley Laboratory.
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  *    notice, this list of conditions and the following disclaimer in the
50  *    documentation and/or other materials provided with the distribution.
51  *
52  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
53  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
54  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
55  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
56  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
57  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
58  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
59  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
60  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
61  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
62  *
63  *	@(#)scsi.c	7.5 (Berkeley) 5/4/91
64  */
65 
66 /*
67  * AMIGA NCR 5380 scsi adaptor driver
68  */
69 
70 #include <sys/cdefs.h>
71 __KERNEL_RCSID(0, "$NetBSD: sci.c,v 1.34 2010/12/20 00:25:26 matt Exp $");
72 
73 #include <sys/param.h>
74 #include <sys/systm.h>
75 #include <sys/device.h>
76 #include <sys/disklabel.h>
77 #include <sys/buf.h>
78 #include <dev/scsipi/scsi_all.h>
79 #include <dev/scsipi/scsipi_all.h>
80 #include <dev/scsipi/scsiconf.h>
81 #include <machine/cpu.h>
82 #include <amiga/amiga/device.h>
83 #include <amiga/amiga/custom.h>
84 #include <amiga/amiga/isr.h>
85 #include <amiga/dev/scireg.h>
86 #include <amiga/dev/scivar.h>
87 
88 /*
89  * SCSI delays
90  * In u-seconds, primarily for state changes on the SPC.
91  */
92 #define	SCI_CMD_WAIT	50000	/* wait per step of 'immediate' cmds */
93 #define	SCI_DATA_WAIT	50000	/* wait per data in/out step */
94 #define	SCI_INIT_WAIT	50000	/* wait per step (both) during init */
95 
96 int  sciicmd(struct sci_softc *, int, void *, int, void *, int,u_char);
97 int  scigo(struct sci_softc *, struct scsipi_xfer *);
98 int  sciselectbus(struct sci_softc *, u_char, u_char);
99 void sciabort(struct sci_softc *, const char *);
100 void scierror(struct sci_softc *, u_char);
101 void scisetdelay(int);
102 void sci_scsidone(struct sci_softc *, int);
103 void sci_donextcmd(struct sci_softc *);
104 int  sci_ixfer_out(struct sci_softc *, int, register u_char *, int);
105 void sci_ixfer_in(struct sci_softc *, int, register u_char *, int);
106 
107 int sci_cmd_wait = SCI_CMD_WAIT;
108 int sci_data_wait = SCI_DATA_WAIT;
109 int sci_init_wait = SCI_INIT_WAIT;
110 
111 int sci_no_dma = 0;
112 
113 #ifdef DEBUG
114 #define QPRINTF(a) if (sci_debug > 1) printf a
115 int	sci_debug = 0;
116 #else
117 #define QPRINTF(a)
118 #endif
119 
120 /*
121  * default minphys routine for sci based controllers
122  */
123 void
124 sci_minphys(struct buf *bp)
125 {
126 
127 	/*
128 	 * No max transfer at this level.
129 	 */
130 	minphys(bp);
131 }
132 
133 /*
134  * used by specific sci controller
135  *
136  * it appears that the higher level code does nothing with LUN's
137  * so I will too.  I could plug it in, however so could they
138  * in scsi_scsipi_cmd().
139  */
140 void
141 sci_scsipi_request(struct scsipi_channel *chan, scsipi_adapter_req_t req,
142                    void *arg)
143 {
144 	struct scsipi_xfer *xs;
145 	struct scsipi_periph *periph;
146 	struct sci_softc *dev = (void *)chan->chan_adapter->adapt_dev;
147 	int flags, s;
148 
149 	switch (req) {
150 	case ADAPTER_REQ_RUN_XFER:
151 		xs = arg;
152 		periph = xs->xs_periph;
153 		flags = xs->xs_control;
154 
155 		if (flags & XS_CTL_DATA_UIO)
156 		panic("sci: scsi data uio requested");
157 
158 		s = splbio();
159 
160 		if (dev->sc_xs && flags & XS_CTL_POLL)
161 			panic("sci_scsicmd: busy");
162 
163 #ifdef DIAGNOSTIC
164 		/*
165 		 * This should never happen as we track the resources
166 		 * in the mid-layer.
167 		 */
168 		if (dev->sc_xs) {
169 			scsipi_printaddr(periph);
170 			printf("unable to allocate scb\n");
171 			panic("sea_scsipi_request");
172 		}
173 #endif
174 
175 		dev->sc_xs = xs;
176 		splx(s);
177 
178 		/*
179 		 * nothing is pending do it now.
180 		 */
181 		sci_donextcmd(dev);
182 
183 		return;
184 
185 	case ADAPTER_REQ_GROW_RESOURCES:
186 		return;
187 
188 	case ADAPTER_REQ_SET_XFER_MODE:
189 		return;
190 	}
191 }
192 
193 /*
194  * entered with dev->sc_xs pointing to the next xfer to perform
195  */
196 void
197 sci_donextcmd(struct sci_softc *dev)
198 {
199 	struct scsipi_xfer *xs;
200 	struct scsipi_periph *periph;
201 	int flags, phase, stat;
202 
203 	xs = dev->sc_xs;
204 	periph = xs->xs_periph;
205 	flags = xs->xs_control;
206 
207 	if (flags & XS_CTL_DATA_IN)
208 		phase = DATA_IN_PHASE;
209 	else if (flags & XS_CTL_DATA_OUT)
210 		phase = DATA_OUT_PHASE;
211 	else
212 		phase = STATUS_PHASE;
213 
214 	if (flags & XS_CTL_RESET)
215 		scireset(dev);
216 
217 	dev->sc_stat[0] = -1;
218 	xs->cmd->bytes[0] |= periph->periph_lun << 5;
219 	if (phase == STATUS_PHASE || flags & XS_CTL_POLL)
220 		stat = sciicmd(dev, periph->periph_target, xs->cmd, xs->cmdlen,
221 		    xs->data, xs->datalen, phase);
222 	else if (scigo(dev, xs) == 0)
223 		return;
224 	else
225 		stat = dev->sc_stat[0];
226 
227 	sci_scsidone(dev, stat);
228 }
229 
230 void
231 sci_scsidone(struct sci_softc *dev, int stat)
232 {
233 	struct scsipi_xfer *xs;
234 
235 	xs = dev->sc_xs;
236 #ifdef DIAGNOSTIC
237 	if (xs == NULL)
238 		panic("sci_scsidone");
239 #endif
240 	xs->status = stat;
241 	if (stat == 0)
242 		xs->resid = 0;
243 	else {
244 		switch(stat) {
245 		case SCSI_CHECK:
246 			xs->resid = 0;
247 			/* FALLTHROUGH */
248 		case SCSI_BUSY:
249 			xs->error = XS_BUSY;
250 			break;
251 		default:
252 			xs->error = XS_DRIVER_STUFFUP;
253 			QPRINTF(("sci_scsicmd() bad %x\n", stat));
254 			break;
255 		}
256 	}
257 
258 	scsipi_done(xs);
259 
260 }
261 
262 void
263 sciabort(struct sci_softc *dev, const char *where)
264 {
265 	printf ("%s: abort %s: csr = 0x%02x, bus = 0x%02x\n",
266 	  dev->sc_dev.dv_xname, where, *dev->sci_csr, *dev->sci_bus_csr);
267 
268 	if (dev->sc_flags & SCI_SELECTED) {
269 
270 		/* lets just hope it worked.. */
271 		dev->sc_flags &= ~SCI_SELECTED;
272 		/* XXX */
273 		scireset (dev);
274 	}
275 }
276 
277 /*
278  * XXX Set/reset long delays.
279  *
280  * if delay == 0, reset default delays
281  * if delay < 0,  set both delays to default long initialization values
282  * if delay > 0,  set both delays to this value
283  *
284  * Used when a devices is expected to respond slowly (e.g. during
285  * initialization).
286  */
287 void
288 scisetdelay(int del)
289 {
290 	static int saved_cmd_wait, saved_data_wait;
291 
292 	if (del) {
293 		saved_cmd_wait = sci_cmd_wait;
294 		saved_data_wait = sci_data_wait;
295 		if (del > 0)
296 			sci_cmd_wait = sci_data_wait = del;
297 		else
298 			sci_cmd_wait = sci_data_wait = sci_init_wait;
299 	} else {
300 		sci_cmd_wait = saved_cmd_wait;
301 		sci_data_wait = saved_data_wait;
302 	}
303 }
304 
305 void
306 scireset(struct sci_softc *dev)
307 {
308 	u_int s;
309 	u_char my_id;
310 
311 	dev->sc_flags &= ~SCI_SELECTED;
312 	if (dev->sc_flags & SCI_ALIVE)
313 		sciabort(dev, "reset");
314 
315 	printf("%s: ", dev->sc_dev.dv_xname);
316 
317 	s = splbio();
318 	/* preserve our ID for now */
319 	my_id = 7;
320 
321 	/*
322 	 * Reset the chip
323 	 */
324 	*dev->sci_icmd = SCI_ICMD_TEST;
325 	*dev->sci_icmd = SCI_ICMD_TEST | SCI_ICMD_RST;
326 	delay (25);
327 	*dev->sci_icmd = 0;
328 
329 	/*
330 	 * Set up various chip parameters
331 	 */
332 	*dev->sci_icmd = 0;
333 	*dev->sci_tcmd = 0;
334 	*dev->sci_sel_enb = 0;
335 
336 	/* anything else was zeroed by reset */
337 
338 	splx (s);
339 
340 	printf("sci id %d\n", my_id);
341 	dev->sc_flags |= SCI_ALIVE;
342 }
343 
344 void
345 scierror(struct sci_softc *dev, u_char csr)
346 {
347 	struct scsipi_xfer *xs;
348 
349 	xs = dev->sc_xs;
350 
351 #ifdef DIAGNOSTIC
352 	if (xs == NULL)
353 		panic("scierror");
354 #endif
355 	if (xs->xs_control & XS_CTL_SILENT)
356 		return;
357 
358 	printf("%s: ", dev->sc_dev.dv_xname);
359 	printf("csr == 0x%02i\n", csr);	/* XXX */
360 }
361 
362 /*
363  * select the bus, return when selected or error.
364  */
365 int
366 sciselectbus(struct sci_softc *dev, u_char target, u_char our_addr)
367 {
368 	register int timeo = 2500;
369 
370 	QPRINTF (("sciselectbus %d\n", target));
371 
372 	/* if we're already selected, return */
373 	if (dev->sc_flags & SCI_SELECTED)	/* XXXX */
374 		return 1;
375 
376 	if ((*dev->sci_bus_csr & (SCI_BUS_BSY|SCI_BUS_SEL)) &&
377 	    (*dev->sci_bus_csr & (SCI_BUS_BSY|SCI_BUS_SEL)) &&
378 	    (*dev->sci_bus_csr & (SCI_BUS_BSY|SCI_BUS_SEL)))
379 		return 1;
380 
381 	*dev->sci_tcmd = 0;
382 	*dev->sci_odata = 0x80 + (1 << target);
383 	*dev->sci_icmd = SCI_ICMD_DATA|SCI_ICMD_SEL;
384 	while ((*dev->sci_bus_csr & SCI_BUS_BSY) == 0) {
385 		if (--timeo > 0) {
386 			delay(100);
387 		} else {
388 			break;
389 		}
390 	}
391 	if (timeo) {
392 		*dev->sci_icmd = 0;
393 		dev->sc_flags |= SCI_SELECTED;
394 		return (0);
395 	}
396 	*dev->sci_icmd = 0;
397 	return (1);
398 }
399 
400 int
401 sci_ixfer_out(register struct sci_softc *dev, int len, register u_char *buf,
402               int phase)
403 {
404 	register int wait = sci_data_wait;
405 	u_char csr;
406 
407 	QPRINTF(("sci_ixfer_out {%d} %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
408 	  len, buf[0], buf[1], buf[2], buf[3], buf[4], buf[5],
409 	  buf[6], buf[7], buf[8], buf[9]));
410 
411 	*dev->sci_tcmd = phase;
412 	*dev->sci_icmd = SCI_ICMD_DATA;
413 	for (;len > 0; len--) {
414 		csr = *dev->sci_bus_csr;
415 		while (!(csr & SCI_BUS_REQ)) {
416 			if ((csr & SCI_BUS_BSY) == 0 || --wait < 0) {
417 #ifdef DEBUG
418 				if (sci_debug)
419 					printf("sci_ixfer_out fail: l%d i%x w%d\n",
420 					  len, csr, wait);
421 #endif
422 				return (len);
423 			}
424 			delay(1);
425 			csr = *dev->sci_bus_csr;
426 		}
427 
428 		if (!(*dev->sci_csr & SCI_CSR_PHASE_MATCH))
429 			break;
430 		*dev->sci_odata = *buf;
431 		*dev->sci_icmd = SCI_ICMD_DATA|SCI_ICMD_ACK;
432 		buf++;
433 		while (*dev->sci_bus_csr & SCI_BUS_REQ);
434 		*dev->sci_icmd = SCI_ICMD_DATA;
435 	}
436 
437 	QPRINTF(("sci_ixfer_out done\n"));
438 	return (0);
439 }
440 
441 void
442 sci_ixfer_in(struct sci_softc *dev, int len, register u_char *buf, int phase)
443 {
444 	int wait = sci_data_wait;
445 	u_char csr;
446 	volatile register u_char *sci_bus_csr = dev->sci_bus_csr;
447 	volatile register u_char *sci_data = dev->sci_data;
448 	volatile register u_char *sci_icmd = dev->sci_icmd;
449 #ifdef DEBUG
450 	u_char *obp = buf;
451 #endif
452 
453 	csr = *sci_bus_csr;
454 
455 	QPRINTF(("sci_ixfer_in %d, csr=%02x\n", len, csr));
456 
457 	*dev->sci_tcmd = phase;
458 	*sci_icmd = 0;
459 	for (;len > 0; len--) {
460 		csr = *sci_bus_csr;
461 		while (!(csr & SCI_BUS_REQ)) {
462 			if (!(csr & SCI_BUS_BSY) || --wait < 0) {
463 #ifdef DEBUG
464 				if (sci_debug)
465 					printf("sci_ixfer_in fail: l%d i%x w%d\n",
466 					len, csr, wait);
467 #endif
468 				return;
469 			}
470 
471 			delay(1);
472 			csr = *sci_bus_csr;
473 		}
474 
475 		if (!(*dev->sci_csr & SCI_CSR_PHASE_MATCH))
476 			break;
477 		*buf = *sci_data;
478 		*sci_icmd = SCI_ICMD_ACK;
479 		buf++;
480 		while (*sci_bus_csr & SCI_BUS_REQ);
481 		*sci_icmd = 0;
482 	}
483 
484 	QPRINTF(("sci_ixfer_in {%d} %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
485 	  len, obp[0], obp[1], obp[2], obp[3], obp[4], obp[5],
486 	  obp[6], obp[7], obp[8], obp[9]));
487 }
488 
489 /*
490  * SCSI 'immediate' command:  issue a command to some SCSI device
491  * and get back an 'immediate' response (i.e., do programmed xfer
492  * to get the response data).  'cbuf' is a buffer containing a scsi
493  * command of length clen bytes.  'buf' is a buffer of length 'len'
494  * bytes for data.  The transfer direction is determined by the device
495  * (i.e., by the scsi bus data xfer phase).  If 'len' is zero, the
496  * command must supply no data.  'xferphase' is the bus phase the
497  * caller expects to happen after the command is issued.  It should
498  * be one of DATA_IN_PHASE, DATA_OUT_PHASE or STATUS_PHASE.
499  */
500 int
501 sciicmd(struct sci_softc *dev, int target, void *cbuf, int clen, void *buf,
502         int len, u_char xferphase)
503 {
504 	u_char phase;
505 	register int wait;
506 
507 	/* select the SCSI bus (it's an error if bus isn't free) */
508 	if (sciselectbus (dev, target, dev->sc_scsi_addr))
509 		return -1;
510 	/*
511 	 * Wait for a phase change (or error) then let the device
512 	 * sequence us through the various SCSI phases.
513 	 */
514 	dev->sc_stat[0] = 0xff;
515 	dev->sc_msg[0] = 0xff;
516 	phase = CMD_PHASE;
517 	while (1) {
518 		wait = sci_cmd_wait;
519 
520 		while ((*dev->sci_bus_csr & (SCI_BUS_REQ|SCI_BUS_BSY)) == SCI_BUS_BSY);
521 
522 		QPRINTF((">CSR:%02x<", *dev->sci_bus_csr));
523 		if ((*dev->sci_bus_csr & SCI_BUS_REQ) == 0) {
524 			return -1;
525 		}
526 		phase = SCI_PHASE(*dev->sci_bus_csr);
527 
528 		switch (phase) {
529 		case CMD_PHASE:
530 			if (sci_ixfer_out (dev, clen, cbuf, phase))
531 				goto abort;
532 			phase = xferphase;
533 			break;
534 
535 		case DATA_IN_PHASE:
536 			if (len <= 0)
537 				goto abort;
538 			wait = sci_data_wait;
539 			sci_ixfer_in (dev, len, buf, phase);
540 			phase = STATUS_PHASE;
541 			break;
542 
543 		case DATA_OUT_PHASE:
544 			if (len <= 0)
545 				goto abort;
546 			wait = sci_data_wait;
547 			if (sci_ixfer_out (dev, len, buf, phase))
548 				goto abort;
549 			phase = STATUS_PHASE;
550 			break;
551 
552 		case MESG_IN_PHASE:
553 			dev->sc_msg[0] = 0xff;
554 			sci_ixfer_in (dev, 1, dev->sc_msg,phase);
555 			dev->sc_flags &= ~SCI_SELECTED;
556 			while (*dev->sci_bus_csr & SCI_BUS_BSY);
557 			goto out;
558 			break;
559 
560 		case MESG_OUT_PHASE:
561 			phase = STATUS_PHASE;
562 			break;
563 
564 		case STATUS_PHASE:
565 			sci_ixfer_in (dev, 1, dev->sc_stat, phase);
566 			phase = MESG_IN_PHASE;
567 			break;
568 
569 		case BUS_FREE_PHASE:
570 			goto out;
571 
572 		default:
573 		printf("sci: unexpected phase %d in icmd from %d\n",
574 		  phase, target);
575 		goto abort;
576 		}
577 #if 0
578 		if (wait <= 0)
579 			goto abort;
580 #endif
581 	}
582 
583 abort:
584 	sciabort(dev, "icmd");
585 out:
586 	QPRINTF(("=STS:%02x=", dev->sc_stat[0]));
587 	return (dev->sc_stat[0]);
588 }
589 
590 int
591 scigo(struct sci_softc *dev, struct scsipi_xfer *xs)
592 {
593 	int count, target;
594 	u_char phase, *addr;
595 
596 	target = xs->xs_periph->periph_target;
597 	count = xs->datalen;
598 	addr = xs->data;
599 
600 	if (sci_no_dma)	{
601 		sciicmd (dev, target, (u_char *) xs->cmd, xs->cmdlen,
602 		  addr, count,
603 		  xs->xs_control & XS_CTL_DATA_IN ? DATA_IN_PHASE : DATA_OUT_PHASE);
604 
605 		return (1);
606 	}
607 
608 	/* select the SCSI bus (it's an error if bus isn't free) */
609 	if (sciselectbus (dev, target, dev->sc_scsi_addr))
610 		return -1;
611 	/*
612 	 * Wait for a phase change (or error) then let the device
613 	 * sequence us through the various SCSI phases.
614 	 */
615 	dev->sc_stat[0] = 0xff;
616 	dev->sc_msg[0] = 0xff;
617 	phase = CMD_PHASE;
618 	while (1) {
619 		while ((*dev->sci_bus_csr & (SCI_BUS_REQ|SCI_BUS_BSY)) ==
620 		  SCI_BUS_BSY);
621 
622 		QPRINTF((">CSR:%02x<", *dev->sci_bus_csr));
623 		if ((*dev->sci_bus_csr & SCI_BUS_REQ) == 0) {
624 			goto abort;
625 		}
626 		phase = SCI_PHASE(*dev->sci_bus_csr);
627 
628 		switch (phase) {
629 		case CMD_PHASE:
630 			if (sci_ixfer_out (dev, xs->cmdlen, (u_char *) xs->cmd, phase))
631 				goto abort;
632 			phase = xs->xs_control & XS_CTL_DATA_IN ? DATA_IN_PHASE : DATA_OUT_PHASE;
633 			break;
634 
635 		case DATA_IN_PHASE:
636 			if (count <= 0)
637 				goto abort;
638 			/* XXX use psuedo DMA if available */
639 			if (count >= 128 && dev->dma_xfer_in)
640 				(*dev->dma_xfer_in)(dev, count, addr, phase);
641 			else
642 				sci_ixfer_in (dev, count, addr, phase);
643 			phase = STATUS_PHASE;
644 			break;
645 
646 		case DATA_OUT_PHASE:
647 			if (count <= 0)
648 				goto abort;
649 			/* XXX use psuedo DMA if available */
650 			if (count >= 128 && dev->dma_xfer_out)
651 				(*dev->dma_xfer_out)(dev, count, addr, phase);
652 			else
653 				if (sci_ixfer_out (dev, count, addr, phase))
654 					goto abort;
655 			phase = STATUS_PHASE;
656 			break;
657 
658 		case MESG_IN_PHASE:
659 			dev->sc_msg[0] = 0xff;
660 			sci_ixfer_in (dev, 1, dev->sc_msg,phase);
661 			dev->sc_flags &= ~SCI_SELECTED;
662 			while (*dev->sci_bus_csr & SCI_BUS_BSY);
663 			goto out;
664 			break;
665 
666 		case MESG_OUT_PHASE:
667 			phase = STATUS_PHASE;
668 			break;
669 
670 		case STATUS_PHASE:
671 			sci_ixfer_in (dev, 1, dev->sc_stat, phase);
672 			phase = MESG_IN_PHASE;
673 			break;
674 
675 		case BUS_FREE_PHASE:
676 			goto out;
677 
678 		default:
679 		printf("sci: unexpected phase %d in icmd from %d\n",
680 		  phase, target);
681 		goto abort;
682 		}
683 	}
684 
685 abort:
686 	sciabort(dev, "go");
687 out:
688 	QPRINTF(("=STS:%02x=", dev->sc_stat[0]));
689 	return (1);
690 }
691