xref: /netbsd-src/sys/arch/amiga/dev/sci.c (revision eb7c1594f145c931049e1fd9eb056a5987e87e59)
1 /*	$NetBSD: sci.c,v 1.29 2003/08/07 16:26:43 agc 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  * 3. All advertising materials mentioning features or use of this software
52  *    must display the following acknowledgement:
53  *	This product includes software developed by the University of
54  *	California, Berkeley and its contributors.
55  * 4. Neither the name of the University nor the names of its contributors
56  *    may be used to endorse or promote products derived from this software
57  *    without specific prior written permission.
58  *
59  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
60  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
61  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
62  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
63  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
64  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
65  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
66  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
67  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
68  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
69  * SUCH DAMAGE.
70  *
71  *	@(#)scsi.c	7.5 (Berkeley) 5/4/91
72  */
73 
74 /*
75  * AMIGA NCR 5380 scsi adaptor driver
76  */
77 
78 #include <sys/cdefs.h>
79 __KERNEL_RCSID(0, "$NetBSD: sci.c,v 1.29 2003/08/07 16:26:43 agc Exp $");
80 
81 #include <sys/param.h>
82 #include <sys/systm.h>
83 #include <sys/device.h>
84 #include <sys/disklabel.h>
85 #include <sys/buf.h>
86 #include <dev/scsipi/scsi_all.h>
87 #include <dev/scsipi/scsipi_all.h>
88 #include <dev/scsipi/scsiconf.h>
89 #include <uvm/uvm_extern.h>
90 #include <machine/pmap.h>
91 #include <machine/cpu.h>
92 #include <amiga/amiga/device.h>
93 #include <amiga/amiga/custom.h>
94 #include <amiga/amiga/isr.h>
95 #include <amiga/dev/scireg.h>
96 #include <amiga/dev/scivar.h>
97 
98 /*
99  * SCSI delays
100  * In u-seconds, primarily for state changes on the SPC.
101  */
102 #define	SCI_CMD_WAIT	50000	/* wait per step of 'immediate' cmds */
103 #define	SCI_DATA_WAIT	50000	/* wait per data in/out step */
104 #define	SCI_INIT_WAIT	50000	/* wait per step (both) during init */
105 
106 int  sciicmd(struct sci_softc *, int, void *, int, void *, int,u_char);
107 int  scigo(struct sci_softc *, struct scsipi_xfer *);
108 int  sciselectbus(struct sci_softc *, u_char, u_char);
109 void sciabort(struct sci_softc *, char *);
110 void scierror(struct sci_softc *, u_char);
111 void scisetdelay(int);
112 void sci_scsidone(struct sci_softc *, int);
113 void sci_donextcmd(struct sci_softc *);
114 int  sci_ixfer_out(struct sci_softc *, int, register u_char *, int);
115 void sci_ixfer_in(struct sci_softc *, int, register u_char *, int);
116 
117 int sci_cmd_wait = SCI_CMD_WAIT;
118 int sci_data_wait = SCI_DATA_WAIT;
119 int sci_init_wait = SCI_INIT_WAIT;
120 
121 int sci_no_dma = 0;
122 
123 #ifdef DEBUG
124 #define QPRINTF(a) if (sci_debug > 1) printf a
125 int	sci_debug = 0;
126 #else
127 #define QPRINTF(a)
128 #endif
129 
130 /*
131  * default minphys routine for sci based controllers
132  */
133 void
134 sci_minphys(struct buf *bp)
135 {
136 
137 	/*
138 	 * No max transfer at this level.
139 	 */
140 	minphys(bp);
141 }
142 
143 /*
144  * used by specific sci controller
145  *
146  * it appears that the higher level code does nothing with LUN's
147  * so I will too.  I could plug it in, however so could they
148  * in scsi_scsipi_cmd().
149  */
150 void
151 sci_scsipi_request(struct scsipi_channel *chan, scsipi_adapter_req_t req,
152                    void *arg)
153 {
154 	struct scsipi_xfer *xs;
155 	struct scsipi_periph *periph;
156 	struct sci_softc *dev = (void *)chan->chan_adapter->adapt_dev;
157 	int flags, s;
158 
159 	switch (req) {
160 	case ADAPTER_REQ_RUN_XFER:
161 		xs = arg;
162 		periph = xs->xs_periph;
163 		flags = xs->xs_control;
164 
165 		if (flags & XS_CTL_DATA_UIO)
166 		panic("sci: scsi data uio requested");
167 
168 		if (dev->sc_xs && flags & XS_CTL_POLL)
169 			panic("sci_scsicmd: busy");
170 
171 #ifdef DIAGNOSTIC
172 		/*
173 		 * This should never happen as we track the resources
174 		 * in the mid-layer.
175 		 */
176 		if (dev->sc_xs) {
177 			scsipi_printaddr(periph);
178 			printf("unable to allocate scb\n");
179 			panic("sea_scsipi_request");
180 		}
181 #endif
182 
183 		dev->sc_xs = xs;
184 		splx(s);
185 
186 		/*
187 		 * nothing is pending do it now.
188 		 */
189 		sci_donextcmd(dev);
190 
191 		return;
192 
193 	case ADAPTER_REQ_GROW_RESOURCES:
194 		return;
195 
196 	case ADAPTER_REQ_SET_XFER_MODE:
197 		return;
198 	}
199 }
200 
201 /*
202  * entered with dev->sc_xs pointing to the next xfer to perform
203  */
204 void
205 sci_donextcmd(struct sci_softc *dev)
206 {
207 	struct scsipi_xfer *xs;
208 	struct scsipi_periph *periph;
209 	int flags, phase, stat;
210 
211 	xs = dev->sc_xs;
212 	periph = xs->xs_periph;
213 	flags = xs->xs_control;
214 
215 	if (flags & XS_CTL_DATA_IN)
216 		phase = DATA_IN_PHASE;
217 	else if (flags & XS_CTL_DATA_OUT)
218 		phase = DATA_OUT_PHASE;
219 	else
220 		phase = STATUS_PHASE;
221 
222 	if (flags & XS_CTL_RESET)
223 		scireset(dev);
224 
225 	dev->sc_stat[0] = -1;
226 	xs->cmd->bytes[0] |= periph->periph_lun << 5;
227 	if (phase == STATUS_PHASE || flags & XS_CTL_POLL)
228 		stat = sciicmd(dev, periph->periph_target, xs->cmd, xs->cmdlen,
229 		    xs->data, xs->datalen, phase);
230 	else if (scigo(dev, xs) == 0)
231 		return;
232 	else
233 		stat = dev->sc_stat[0];
234 
235 	sci_scsidone(dev, stat);
236 }
237 
238 void
239 sci_scsidone(struct sci_softc *dev, int stat)
240 {
241 	struct scsipi_xfer *xs;
242 
243 	xs = dev->sc_xs;
244 #ifdef DIAGNOSTIC
245 	if (xs == NULL)
246 		panic("sci_scsidone");
247 #endif
248 	xs->status = stat;
249 	if (stat == 0)
250 		xs->resid = 0;
251 	else {
252 		switch(stat) {
253 		case SCSI_CHECK:
254 			xs->resid = 0;
255 			/* FALLTHOUGH */
256 		case SCSI_BUSY:
257 			xs->error = XS_BUSY;
258 			break;
259 		default:
260 			xs->error = XS_DRIVER_STUFFUP;
261 			QPRINTF(("sci_scsicmd() bad %x\n", stat));
262 			break;
263 		}
264 	}
265 
266 	scsipi_done(xs);
267 
268 }
269 
270 void
271 sciabort(struct sci_softc *dev, char *where)
272 {
273 	printf ("%s: abort %s: csr = 0x%02x, bus = 0x%02x\n",
274 	  dev->sc_dev.dv_xname, where, *dev->sci_csr, *dev->sci_bus_csr);
275 
276 	if (dev->sc_flags & SCI_SELECTED) {
277 
278 		/* lets just hope it worked.. */
279 		dev->sc_flags &= ~SCI_SELECTED;
280 		/* XXX */
281 		scireset (dev);
282 	}
283 }
284 
285 /*
286  * XXX Set/reset long delays.
287  *
288  * if delay == 0, reset default delays
289  * if delay < 0,  set both delays to default long initialization values
290  * if delay > 0,  set both delays to this value
291  *
292  * Used when a devices is expected to respond slowly (e.g. during
293  * initialization).
294  */
295 void
296 scisetdelay(int del)
297 {
298 	static int saved_cmd_wait, saved_data_wait;
299 
300 	if (del) {
301 		saved_cmd_wait = sci_cmd_wait;
302 		saved_data_wait = sci_data_wait;
303 		if (del > 0)
304 			sci_cmd_wait = sci_data_wait = del;
305 		else
306 			sci_cmd_wait = sci_data_wait = sci_init_wait;
307 	} else {
308 		sci_cmd_wait = saved_cmd_wait;
309 		sci_data_wait = saved_data_wait;
310 	}
311 }
312 
313 void
314 scireset(struct sci_softc *dev)
315 {
316 	u_int s;
317 	u_char my_id;
318 
319 	dev->sc_flags &= ~SCI_SELECTED;
320 	if (dev->sc_flags & SCI_ALIVE)
321 		sciabort(dev, "reset");
322 
323 	printf("%s: ", dev->sc_dev.dv_xname);
324 
325 	s = splbio();
326 	/* preserve our ID for now */
327 	my_id = 7;
328 
329 	/*
330 	 * Reset the chip
331 	 */
332 	*dev->sci_icmd = SCI_ICMD_TEST;
333 	*dev->sci_icmd = SCI_ICMD_TEST | SCI_ICMD_RST;
334 	delay (25);
335 	*dev->sci_icmd = 0;
336 
337 	/*
338 	 * Set up various chip parameters
339 	 */
340 	*dev->sci_icmd = 0;
341 	*dev->sci_tcmd = 0;
342 	*dev->sci_sel_enb = 0;
343 
344 	/* anything else was zeroed by reset */
345 
346 	splx (s);
347 
348 	printf("sci id %d\n", my_id);
349 	dev->sc_flags |= SCI_ALIVE;
350 }
351 
352 void
353 scierror(struct sci_softc *dev, u_char csr)
354 {
355 	struct scsipi_xfer *xs;
356 
357 	xs = dev->sc_xs;
358 
359 #ifdef DIAGNOSTIC
360 	if (xs == NULL)
361 		panic("scierror");
362 #endif
363 	if (xs->xs_control & XS_CTL_SILENT)
364 		return;
365 
366 	printf("%s: ", dev->sc_dev.dv_xname);
367 	printf("csr == 0x%02i\n", csr);	/* XXX */
368 }
369 
370 /*
371  * select the bus, return when selected or error.
372  */
373 int
374 sciselectbus(struct sci_softc *dev, u_char target, u_char our_addr)
375 {
376 	register int timeo = 2500;
377 
378 	QPRINTF (("sciselectbus %d\n", target));
379 
380 	/* if we're already selected, return */
381 	if (dev->sc_flags & SCI_SELECTED)	/* XXXX */
382 		return 1;
383 
384 	if ((*dev->sci_bus_csr & (SCI_BUS_BSY|SCI_BUS_SEL)) &&
385 	    (*dev->sci_bus_csr & (SCI_BUS_BSY|SCI_BUS_SEL)) &&
386 	    (*dev->sci_bus_csr & (SCI_BUS_BSY|SCI_BUS_SEL)))
387 		return 1;
388 
389 	*dev->sci_tcmd = 0;
390 	*dev->sci_odata = 0x80 + (1 << target);
391 	*dev->sci_icmd = SCI_ICMD_DATA|SCI_ICMD_SEL;
392 	while ((*dev->sci_bus_csr & SCI_BUS_BSY) == 0) {
393 		if (--timeo > 0) {
394 			delay(100);
395 		} else {
396 			break;
397 		}
398 	}
399 	if (timeo) {
400 		*dev->sci_icmd = 0;
401 		dev->sc_flags |= SCI_SELECTED;
402 		return (0);
403 	}
404 	*dev->sci_icmd = 0;
405 	return (1);
406 }
407 
408 int
409 sci_ixfer_out(register struct sci_softc *dev, int len, register u_char *buf,
410               int phase)
411 {
412 	register int wait = sci_data_wait;
413 	u_char csr;
414 
415 	QPRINTF(("sci_ixfer_out {%d} %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
416 	  len, buf[0], buf[1], buf[2], buf[3], buf[4], buf[5],
417 	  buf[6], buf[7], buf[8], buf[9]));
418 
419 	*dev->sci_tcmd = phase;
420 	*dev->sci_icmd = SCI_ICMD_DATA;
421 	for (;len > 0; len--) {
422 		csr = *dev->sci_bus_csr;
423 		while (!(csr & SCI_BUS_REQ)) {
424 			if ((csr & SCI_BUS_BSY) == 0 || --wait < 0) {
425 #ifdef DEBUG
426 				if (sci_debug)
427 					printf("sci_ixfer_out fail: l%d i%x w%d\n",
428 					  len, csr, wait);
429 #endif
430 				return (len);
431 			}
432 			delay(1);
433 			csr = *dev->sci_bus_csr;
434 		}
435 
436 		if (!(*dev->sci_csr & SCI_CSR_PHASE_MATCH))
437 			break;
438 		*dev->sci_odata = *buf;
439 		*dev->sci_icmd = SCI_ICMD_DATA|SCI_ICMD_ACK;
440 		buf++;
441 		while (*dev->sci_bus_csr & SCI_BUS_REQ);
442 		*dev->sci_icmd = SCI_ICMD_DATA;
443 	}
444 
445 	QPRINTF(("sci_ixfer_out done\n"));
446 	return (0);
447 }
448 
449 void
450 sci_ixfer_in(struct sci_softc *dev, int len, register u_char *buf, int phase)
451 {
452 	int wait = sci_data_wait;
453 	u_char csr;
454 	volatile register u_char *sci_bus_csr = dev->sci_bus_csr;
455 	volatile register u_char *sci_data = dev->sci_data;
456 	volatile register u_char *sci_icmd = dev->sci_icmd;
457 #ifdef DEBUG
458 	u_char *obp = buf;
459 #endif
460 
461 	csr = *sci_bus_csr;
462 
463 	QPRINTF(("sci_ixfer_in %d, csr=%02x\n", len, csr));
464 
465 	*dev->sci_tcmd = phase;
466 	*sci_icmd = 0;
467 	for (;len > 0; len--) {
468 		csr = *sci_bus_csr;
469 		while (!(csr & SCI_BUS_REQ)) {
470 			if (!(csr & SCI_BUS_BSY) || --wait < 0) {
471 #ifdef DEBUG
472 				if (sci_debug)
473 					printf("sci_ixfer_in fail: l%d i%x w%d\n",
474 					len, csr, wait);
475 #endif
476 				return;
477 			}
478 
479 			delay(1);
480 			csr = *sci_bus_csr;
481 		}
482 
483 		if (!(*dev->sci_csr & SCI_CSR_PHASE_MATCH))
484 			break;
485 		*buf = *sci_data;
486 		*sci_icmd = SCI_ICMD_ACK;
487 		buf++;
488 		while (*sci_bus_csr & SCI_BUS_REQ);
489 		*sci_icmd = 0;
490 	}
491 
492 	QPRINTF(("sci_ixfer_in {%d} %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
493 	  len, obp[0], obp[1], obp[2], obp[3], obp[4], obp[5],
494 	  obp[6], obp[7], obp[8], obp[9]));
495 }
496 
497 /*
498  * SCSI 'immediate' command:  issue a command to some SCSI device
499  * and get back an 'immediate' response (i.e., do programmed xfer
500  * to get the response data).  'cbuf' is a buffer containing a scsi
501  * command of length clen bytes.  'buf' is a buffer of length 'len'
502  * bytes for data.  The transfer direction is determined by the device
503  * (i.e., by the scsi bus data xfer phase).  If 'len' is zero, the
504  * command must supply no data.  'xferphase' is the bus phase the
505  * caller expects to happen after the command is issued.  It should
506  * be one of DATA_IN_PHASE, DATA_OUT_PHASE or STATUS_PHASE.
507  */
508 int
509 sciicmd(struct sci_softc *dev, int target, void *cbuf, int clen, void *buf,
510         int len, u_char xferphase)
511 {
512 	u_char phase;
513 	register int wait;
514 
515 	/* select the SCSI bus (it's an error if bus isn't free) */
516 	if (sciselectbus (dev, target, dev->sc_scsi_addr))
517 		return -1;
518 	/*
519 	 * Wait for a phase change (or error) then let the device
520 	 * sequence us through the various SCSI phases.
521 	 */
522 	dev->sc_stat[0] = 0xff;
523 	dev->sc_msg[0] = 0xff;
524 	phase = CMD_PHASE;
525 	while (1) {
526 		wait = sci_cmd_wait;
527 
528 		while ((*dev->sci_bus_csr & (SCI_BUS_REQ|SCI_BUS_BSY)) == SCI_BUS_BSY);
529 
530 		QPRINTF((">CSR:%02x<", *dev->sci_bus_csr));
531 		if ((*dev->sci_bus_csr & SCI_BUS_REQ) == 0) {
532 			return -1;
533 		}
534 		phase = SCI_PHASE(*dev->sci_bus_csr);
535 
536 		switch (phase) {
537 		case CMD_PHASE:
538 			if (sci_ixfer_out (dev, clen, cbuf, phase))
539 				goto abort;
540 			phase = xferphase;
541 			break;
542 
543 		case DATA_IN_PHASE:
544 			if (len <= 0)
545 				goto abort;
546 			wait = sci_data_wait;
547 			sci_ixfer_in (dev, len, buf, phase);
548 			phase = STATUS_PHASE;
549 			break;
550 
551 		case DATA_OUT_PHASE:
552 			if (len <= 0)
553 				goto abort;
554 			wait = sci_data_wait;
555 			if (sci_ixfer_out (dev, len, buf, phase))
556 				goto abort;
557 			phase = STATUS_PHASE;
558 			break;
559 
560 		case MESG_IN_PHASE:
561 			dev->sc_msg[0] = 0xff;
562 			sci_ixfer_in (dev, 1, dev->sc_msg,phase);
563 			dev->sc_flags &= ~SCI_SELECTED;
564 			while (*dev->sci_bus_csr & SCI_BUS_BSY);
565 			goto out;
566 			break;
567 
568 		case MESG_OUT_PHASE:
569 			phase = STATUS_PHASE;
570 			break;
571 
572 		case STATUS_PHASE:
573 			sci_ixfer_in (dev, 1, dev->sc_stat, phase);
574 			phase = MESG_IN_PHASE;
575 			break;
576 
577 		case BUS_FREE_PHASE:
578 			goto out;
579 
580 		default:
581 		printf("sci: unexpected phase %d in icmd from %d\n",
582 		  phase, target);
583 		goto abort;
584 		}
585 #if 0
586 		if (wait <= 0)
587 			goto abort;
588 #endif
589 	}
590 
591 abort:
592 	sciabort(dev, "icmd");
593 out:
594 	QPRINTF(("=STS:%02x=", dev->sc_stat[0]));
595 	return (dev->sc_stat[0]);
596 }
597 
598 int
599 scigo(struct sci_softc *dev, struct scsipi_xfer *xs)
600 {
601 	int count, target;
602 	u_char phase, *addr;
603 
604 	target = xs->xs_periph->periph_target;
605 	count = xs->datalen;
606 	addr = xs->data;
607 
608 	if (sci_no_dma)	{
609 		sciicmd (dev, target, (u_char *) xs->cmd, xs->cmdlen,
610 		  addr, count,
611 		  xs->xs_control & XS_CTL_DATA_IN ? DATA_IN_PHASE : DATA_OUT_PHASE);
612 
613 		return (1);
614 	}
615 
616 	/* select the SCSI bus (it's an error if bus isn't free) */
617 	if (sciselectbus (dev, target, dev->sc_scsi_addr))
618 		return -1;
619 	/*
620 	 * Wait for a phase change (or error) then let the device
621 	 * sequence us through the various SCSI phases.
622 	 */
623 	dev->sc_stat[0] = 0xff;
624 	dev->sc_msg[0] = 0xff;
625 	phase = CMD_PHASE;
626 	while (1) {
627 		while ((*dev->sci_bus_csr & (SCI_BUS_REQ|SCI_BUS_BSY)) ==
628 		  SCI_BUS_BSY);
629 
630 		QPRINTF((">CSR:%02x<", *dev->sci_bus_csr));
631 		if ((*dev->sci_bus_csr & SCI_BUS_REQ) == 0) {
632 			goto abort;
633 		}
634 		phase = SCI_PHASE(*dev->sci_bus_csr);
635 
636 		switch (phase) {
637 		case CMD_PHASE:
638 			if (sci_ixfer_out (dev, xs->cmdlen, (u_char *) xs->cmd, phase))
639 				goto abort;
640 			phase = xs->xs_control & XS_CTL_DATA_IN ? DATA_IN_PHASE : DATA_OUT_PHASE;
641 			break;
642 
643 		case DATA_IN_PHASE:
644 			if (count <= 0)
645 				goto abort;
646 			/* XXX use psuedo DMA if available */
647 			if (count >= 128 && dev->dma_xfer_in)
648 				(*dev->dma_xfer_in)(dev, count, addr, phase);
649 			else
650 				sci_ixfer_in (dev, count, addr, phase);
651 			phase = STATUS_PHASE;
652 			break;
653 
654 		case DATA_OUT_PHASE:
655 			if (count <= 0)
656 				goto abort;
657 			/* XXX use psuedo DMA if available */
658 			if (count >= 128 && dev->dma_xfer_out)
659 				(*dev->dma_xfer_out)(dev, count, addr, phase);
660 			else
661 				if (sci_ixfer_out (dev, count, addr, phase))
662 					goto abort;
663 			phase = STATUS_PHASE;
664 			break;
665 
666 		case MESG_IN_PHASE:
667 			dev->sc_msg[0] = 0xff;
668 			sci_ixfer_in (dev, 1, dev->sc_msg,phase);
669 			dev->sc_flags &= ~SCI_SELECTED;
670 			while (*dev->sci_bus_csr & SCI_BUS_BSY);
671 			goto out;
672 			break;
673 
674 		case MESG_OUT_PHASE:
675 			phase = STATUS_PHASE;
676 			break;
677 
678 		case STATUS_PHASE:
679 			sci_ixfer_in (dev, 1, dev->sc_stat, phase);
680 			phase = MESG_IN_PHASE;
681 			break;
682 
683 		case BUS_FREE_PHASE:
684 			goto out;
685 
686 		default:
687 		printf("sci: unexpected phase %d in icmd from %d\n",
688 		  phase, target);
689 		goto abort;
690 		}
691 	}
692 
693 abort:
694 	sciabort(dev, "go");
695 out:
696 	QPRINTF(("=STS:%02x=", dev->sc_stat[0]));
697 	return (1);
698 }
699