xref: /netbsd-src/sys/arch/pmax/ibus/sii.c (revision 404fbe5fb94ca1e054339640cabb2801ce52dd30)
1 /*	$NetBSD: sii.c,v 1.4 2007/10/17 19:56:15 garbled Exp $	*/
2 
3 /*-
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Ralph Campbell and Rick Macklem.
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  *	@(#)sii.c	8.2 (Berkeley) 11/30/93
35  *
36  * from: Header: /sprite/src/kernel/dev/ds3100.md/RCS/devSII.c,
37  *	v 9.2 89/09/14 13:37:41 jhh Exp $ SPRITE (DECWRL)";
38  */
39 
40 #include <sys/cdefs.h>
41 __KERNEL_RCSID(0, "$NetBSD: sii.c,v 1.4 2007/10/17 19:56:15 garbled Exp $");
42 
43 #include "sii.h"
44 /*
45  * SCSI interface driver
46  */
47 #include <sys/param.h>
48 #include <sys/buf.h>
49 #include <sys/conf.h>
50 #include <sys/device.h>
51 #include <sys/systm.h>
52 
53 #include <machine/locore.h>
54 
55 #include <dev/scsipi/scsi_all.h>
56 #include <dev/scsipi/scsi_message.h>
57 #include <dev/scsipi/scsipi_all.h>
58 #include <dev/scsipi/scsipi_disk.h>
59 #include <dev/scsipi/scsiconf.h>
60 
61 /* old 4.4BSD/pmax scsi drivers */
62 #include <pmax/ibus/siireg.h>		/* device registers */
63 #include <pmax/ibus/siivar.h>		/* softc and prototypes */
64 
65 #include <pmax/pmax/machdep.h>		/* prom_scsiid prototype */
66 
67 /* XXX not in dev/scsipi/scsi_message.h */
68 #define	MSG_EXT_MODIFY_DATA_PTR		0x00
69 
70 extern struct cfdriver sii_cd;
71 
72 /*
73  * MACROS for timing out spin loops.
74  *
75  * Wait until expression is true.
76  *
77  * Control register bits can change at any time so when the CPU
78  * reads a register, the bits might change and
79  * invalidate the setup and hold times for the CPU.
80  * This macro reads the register twice to be sure the value is stable.
81  *
82  *	args:	var 		- variable to save control register contents
83  *		reg		- control register to read
84  *		expr 		- expression to spin on
85  *		spincount 	- maximum number of times through the loop
86  *		cntr		- variable for number of tries
87  */
88 #define	SII_WAIT_UNTIL(var, reg, expr, spincount, cntr) {	\
89 		u_int tmp = reg;				\
90 		for (cntr = 0; cntr < spincount; cntr++) {	\
91 			while (tmp != (var = reg))		\
92 				tmp = var;			\
93 			if (expr)				\
94 				break;				\
95 			if (cntr >= 100)			\
96 				DELAY(100);			\
97 		}						\
98 	}
99 
100 #ifdef DEBUG
101 int	sii_debug = 1;
102 int	sii_debug_cmd;
103 int	sii_debug_bn;
104 int	sii_debug_sz;
105 #define NLOG 16
106 struct sii_log {
107 	u_short	cstat;
108 	u_short	dstat;
109 	u_short	comm;
110 	u_short	msg;
111 	int	rlen;
112 	int	dlen;
113 	int	target;
114 } sii_log[NLOG], *sii_logp = sii_log;
115 #endif
116 
117 static u_char	sii_buf[256];	/* used for extended messages */
118 
119 #define NORESET	0
120 #define RESET	1
121 #define NOWAIT	0
122 #define WAIT	1
123 
124 
125 /*
126  * Define a safe address in the SCSI buffer for doing status & message DMA
127  * XXX why not add another field to softc?
128  */
129 #define SII_BUF_ADDR(sc)	((sc)->sc_buf + SII_MAX_DMA_XFER_LENGTH * 14)
130 
131 /*
132  * Forward references
133  */
134 
135 static void	sii_Reset __P((struct siisoftc *sc, int resetbus));
136 static void	sii_StartCmd __P((struct siisoftc *sc, int target));
137 static void	sii_CmdDone __P((struct siisoftc *sc, int target, int error));
138 static void	sii_DoIntr __P((struct siisoftc *sc, u_int dstat));
139 static void	sii_StateChg __P((struct siisoftc *sc, u_int cstat));
140 static int	sii_GetByte __P((SIIRegs *regs, int phase, int ack));
141 static void	sii_DoSync __P((SIIRegs *regs, State *state));
142 static void	sii_StartDMA __P((SIIRegs *regs, int phase, u_short *dmaAddr,
143 				  int size));
144 
145 #ifdef DEBUG
146 static void	sii_DumpLog __P((void));
147 #endif
148 
149 
150 /*
151  * Match driver based on name
152  */
153 void
154 siiattach(sc)
155 	struct siisoftc *sc;
156 {
157 	int i;
158 
159 	sc->sc_target = -1;	/* no command active */
160 
161 	/*
162 	 * Give each target its own DMA buffer region.
163 	 * Make it big enough for 2 max transfers so we can ping pong buffers
164 	 * while we copy the data.
165 	 */
166 	for (i = 0; i < SII_NCMD; i++) {
167 		sc->sc_st[i].dmaAddr[0] = (u_short *)
168 			sc->sc_buf + 2 * SII_MAX_DMA_XFER_LENGTH * i;
169 		sc->sc_st[i].dmaAddr[1] = sc->sc_st[i].dmaAddr[0] +
170 			SII_MAX_DMA_XFER_LENGTH;
171 	}
172 
173 	sii_Reset(sc, RESET);
174 	printf(": target %d\n", sc->sc_regs->id & SII_IDMSK);
175 
176 	sc->sc_adapter.adapt_dev = &sc->sc_dev;
177 	sc->sc_adapter.adapt_nchannels = 1;
178 	sc->sc_adapter.adapt_openings = 7;
179 	sc->sc_adapter.adapt_max_periph = 1;
180 	sc->sc_adapter.adapt_ioctl = NULL;
181 	sc->sc_adapter.adapt_minphys = minphys;
182 	sc->sc_adapter.adapt_request = sii_scsi_request;
183 
184 	sc->sc_channel.chan_adapter = &sc->sc_adapter;
185 	sc->sc_channel.chan_bustype = &scsi_bustype;
186 	sc->sc_channel.chan_channel = 0;
187 	sc->sc_channel.chan_ntargets = 8;
188 	sc->sc_channel.chan_nluns = 8;
189 	sc->sc_channel.chan_id = sc->sc_regs->id & SII_IDMSK;
190 
191 
192 	/*
193 	 * Now try to attach all the sub-devices
194 	 */
195 	config_found(&sc->sc_dev, &sc->sc_channel, scsiprint);
196 }
197 
198 /*
199  * Start activity on a SCSI device.
200  * We maintain information on each device separately since devices can
201  * connect/disconnect during an operation.
202  */
203 
204 void
205 sii_scsi_request(chan, req, arg)
206 	struct scsipi_channel *chan;
207 	scsipi_adapter_req_t req;
208 	void *arg;
209 {
210 	struct scsipi_xfer *xs;
211 	struct scsipi_periph *periph;
212 	struct siisoftc *sc = (void *)chan->chan_adapter->adapt_dev;
213 	int target;
214 	int s;
215 	int count;
216 
217 	switch (req) {
218 	case ADAPTER_REQ_RUN_XFER:
219 		xs = arg;
220 		periph = xs->xs_periph;
221 		target = periph->periph_target;
222 		s = splbio();
223 		if (sc->sc_cmd[target]) {
224 			splx(s);
225 			xs->error = XS_RESOURCE_SHORTAGE;
226 			scsipi_done(xs);
227 			printf("[busy at start]\n");
228 			return;
229 		}
230 		/*
231 		 * Build a ScsiCmd for this command and start it.
232 		 */
233 		sc->sc_xs[target] = xs;
234 		sc->sc_cmd[target] = &sc->sc_cmd_fake[target];	/* XXX */
235 		sc->sc_cmd[target]->unit = 0;
236 		sc->sc_cmd[target]->flags = 0;
237 		sc->sc_cmd[target]->buflen = xs->datalen;
238 		sc->sc_cmd[target]->buf = xs->data;
239 		sc->sc_cmd[target]->cmdlen = xs->cmdlen;
240 		sc->sc_cmd[target]->cmd = (u_char *)xs->cmd;
241 		sc->sc_cmd[target]->lun = xs->xs_periph->periph_lun;
242 		sii_StartCmd(sc, target);
243 		splx(s);
244 		if ((xs->xs_control & XS_CTL_POLL) == 0)
245 			return;
246 		count = xs->timeout;
247 		while (count) {
248 			if ((xs->xs_status & XS_STS_DONE) != 0)
249 				return;
250 			siiintr(sc);
251 			/* XXX schedule another command? */
252 			DELAY(1000);
253 			--count;
254 		}
255 		xs->error = XS_TIMEOUT;
256 		scsipi_done(xs);
257 		return;
258 	case ADAPTER_REQ_GROW_RESOURCES:
259 		/* XXX Not supported. */
260 		return;
261 
262 	case ADAPTER_REQ_SET_XFER_MODE:
263 		/* XXX Not supported. */
264 		return;
265 	}
266 }
267 
268 /*
269  * Check to see if any SII chips have pending interrupts
270  * and process as appropriate.
271  */
272 int
273 siiintr(xxxsc)
274 	void *xxxsc;
275 {
276 	struct siisoftc *sc = xxxsc;
277 	u_int dstat;
278 
279 	/*
280 	 * Find which controller caused the interrupt.
281 	 */
282 	dstat = sc->sc_regs->dstat;
283 	if (dstat & (SII_CI | SII_DI)) {
284 		sii_DoIntr(sc, dstat);
285 		return (0);	/* XXX */
286 	}
287 
288 	return (1);		/* XXX spurious interrupt? */
289 }
290 
291 /*
292  * Reset the SII chip and do a SCSI reset if 'reset' is true.
293  * NOTE: if !cold && reset, should probably probe for devices
294  * since a SCSI bus reset will set UNIT_ATTENTION.
295  */
296 static void
297 sii_Reset(sc, reset)
298 	struct siisoftc* sc;
299 	int reset;				/* TRUE => reset SCSI bus */
300 {
301 	SIIRegs *regs = sc->sc_regs;
302 
303 #ifdef DEBUG
304 	if (sii_debug > 1)
305 		printf("sii: RESET\n");
306 #endif
307 	/*
308 	 * Reset the SII chip.
309 	 */
310 	regs->comm = SII_CHRESET;
311 	/*
312 	 * Set arbitrated bus mode.
313 	 */
314 	regs->csr = SII_HPM;
315 	/*
316 	 * Set host adapter ID (from PROM sciiidN variable).
317 	 */
318 	/* XXX device_unit() abuse */
319 	regs->id = SII_ID_IO | prom_scsiid(device_unit(&sc->sc_dev));
320 	/*
321 	 * Enable SII to drive the SCSI bus.
322 	 */
323 	regs->dictrl = SII_PRE;
324 	regs->dmctrl = 0;
325 
326 	if (reset) {
327 		int i;
328 
329 		/*
330 		 * Assert SCSI bus reset for at least 25 Usec to clear the
331 		 * world. SII_DO_RST is self clearing.
332 		 * Delay 250 ms before doing any commands.
333 		 */
334 		regs->comm = SII_DO_RST;
335 		wbflush();
336 		DELAY(250000);
337 
338 		/* rearbitrate synchronous offset */
339 		for (i = 0; i < SII_NCMD; i++)
340 			sc->sc_st[i].dmaReqAck = 0;
341 	}
342 
343 	/*
344 	 * Clear any pending interrupts from the reset.
345 	 */
346 	regs->cstat = regs->cstat;
347 	regs->dstat = regs->dstat;
348 	/*
349 	 * Set up SII for arbitrated bus mode, SCSI parity checking,
350 	 * Reselect Enable, and Interrupt Enable.
351 	 */
352 	regs->csr = SII_HPM | SII_RSE | SII_PCE | SII_IE;
353 	wbflush();
354 }
355 
356 /*
357  * Start a SCSI command by sending the cmd data
358  * to a SCSI controller via the SII.
359  * Call the device done proceedure if it can't be started.
360  * NOTE: we should be called with interrupts disabled.
361  */
362 static void
363 sii_StartCmd(sc, target)
364 	struct siisoftc *sc;	/* which SII to use */
365 	int target;		/* which command to start */
366 {
367 	SIIRegs *regs;
368 	ScsiCmd *scsicmd;
369 	State *state;
370 	u_int status;
371 	int error, retval;
372 
373 	/* if another command is currently in progress, just wait */
374 	if (sc->sc_target >= 0)
375 		return;
376 
377 	/* initialize state information for this command */
378 	scsicmd = sc->sc_cmd[target];
379 	state = &sc->sc_st[target];
380 	state->flags = FIRST_DMA;
381 	state->prevComm = 0;
382 	state->dmalen = 0;
383 	state->dmaCurPhase = -1;
384 	state->dmaPrevPhase = -1;
385 	state->dmaBufIndex = 0;
386 	state->cmd = scsicmd->cmd;
387 	state->cmdlen = scsicmd->cmdlen;
388 	if ((state->buflen = scsicmd->buflen) == 0) {
389 		state->dmaDataPhase = -1; /* illegal phase. shouldn't happen */
390 		state->buf = (char *)0;
391 	} else {
392 		state->buf = scsicmd->buf;
393 	}
394 
395 #ifdef DEBUG
396 	if (sii_debug > 1) {
397 		printf("sii_StartCmd: %s target %d cmd 0x%x addr %p size %d DMA %d\n",
398 			sc->sc_dev.dv_xname,
399 			target, scsicmd->cmd[0], scsicmd->buf, scsicmd->buflen,
400 			state->dmaDataPhase);
401 	}
402 	sii_debug_cmd = scsicmd->cmd[0];
403 	if (scsicmd->cmd[0] == READ_10 ||
404 	    scsicmd->cmd[0] == WRITE_10) {
405 		sii_debug_bn = (scsicmd->cmd[2] << 24) |
406 			(scsicmd->cmd[3] << 16) |
407 			(scsicmd->cmd[4] << 8) |
408 			scsicmd->cmd[5];
409 		sii_debug_sz = (scsicmd->cmd[7] << 8) | scsicmd->cmd[8];
410 	} else {
411 		sii_debug_bn = 0;
412 		sii_debug_sz = 0;
413 	}
414 #endif
415 
416 	/* try to select the target */
417 	regs = sc->sc_regs;
418 
419 	/*
420 	 * Another device may have selected us; in which case,
421 	 * this command will be restarted later.
422 	 */
423 	if ((status = regs->dstat) & (SII_CI | SII_DI)) {
424 		sii_DoIntr(sc, status);
425 		return;
426 	}
427 
428 	sc->sc_target = target;
429 #if 0
430 	/* seem to have problems with synchronous transfers */
431 	if (scsicmd->flags & SCSICMD_USE_SYNC) {
432 		printf("sii_StartCmd: doing extended msg\n"); /* XXX */
433 		/*
434 		 * Setup to send both the identify message and the synchronous
435 		 * data transfer request.
436 		 */
437 		sii_buf[0] = MSG_IDENTIFYFLAG | MSG_IDENTIFY_DISCFLAG;
438 		sii_buf[1] = MSG_EXTENDED;
439 		sii_buf[2] = MSG_EXT_SDTR_LEN;
440 		sii_buf[3] = MSG_EXT_SDTR;
441 		sii_buf[4] = 0;
442 		sii_buf[5] = 3;		/* maximum SII chip supports */
443 
444 		state->dmaCurPhase = SII_MSG_OUT_PHASE,
445 		state->dmalen = 6;
446 		sc->sii_copytobuf((u_short *)sii_buf,
447 			(volatile u_short *)SII_BUF_ADDR(sc), 6);
448 		regs->slcsr = target;
449 		regs->dmctrl = state->dmaReqAck;
450 		regs->dmaddrl = (u_short)(SII_BUF_ADDR(sc) >> 1);
451 		regs->dmaddrh = (u_short)(SII_BUF_ADDR(sc) >> 17) & 03;
452 		regs->dmlotc = 6;
453 		regs->comm = SII_DMA | SII_INXFER | SII_SELECT | SII_ATN |
454 			SII_CON | SII_MSG_OUT_PHASE;
455 	} else
456 #endif
457 	{
458 		/* do a chained, select with ATN and programmed I/O command */
459 		regs->data = MSG_IDENTIFYFLAG | MSG_IDENTIFY_DISCFLAG |
460 		    scsicmd->lun;
461 		regs->slcsr = target;
462 		regs->dmctrl = state->dmaReqAck;
463 		regs->comm = SII_INXFER | SII_SELECT | SII_ATN | SII_CON |
464 			SII_MSG_OUT_PHASE;
465 	}
466 	wbflush();
467 
468 	/*
469 	 * Wait for something to happen
470 	 * (should happen soon or we would use interrupts).
471 	 */
472 	SII_WAIT_UNTIL(status, regs->cstat, status & (SII_CI | SII_DI),
473 		SII_WAIT_COUNT/4, retval);
474 
475 	/* check to see if we are connected OK */
476 	if ((status & (SII_RST | SII_SCH | SII_STATE_MSK)) ==
477 	    (SII_SCH | SII_CON)) {
478 		regs->cstat = status;
479 		wbflush();
480 
481 #ifdef DEBUG
482 		sii_logp->target = target;
483 		sii_logp->cstat = status;
484 		sii_logp->dstat = 0;
485 		sii_logp->comm = regs->comm;
486 		sii_logp->msg = -1;
487 		sii_logp->rlen = state->buflen;
488 		sii_logp->dlen = state->dmalen;
489 		if (++sii_logp >= &sii_log[NLOG])
490 			sii_logp = sii_log;
491 #endif
492 
493 		/* wait a short time for command phase */
494 		SII_WAIT_UNTIL(status, regs->dstat, status & SII_MIS,
495 			SII_WAIT_COUNT, retval);
496 #ifdef DEBUG
497 		if (sii_debug > 2)
498 			printf("sii_StartCmd: ds %x cnt %d\n", status, retval);
499 #endif
500 		if ((status & (SII_CI | SII_MIS | SII_PHASE_MSK)) !=
501 		    (SII_MIS | SII_CMD_PHASE)) {
502 			printf("sii_StartCmd: timeout cs %x ds %x cnt %d\n",
503 				regs->cstat, status, retval); /* XXX */
504 			/* process interrupt or continue until it happens */
505 			if (status & (SII_CI | SII_DI))
506 				sii_DoIntr(sc, status);
507 			return;
508 		}
509 		regs->dstat = SII_DNE;	/* clear Msg Out DMA done */
510 
511 		/* send command data */
512 		sc->sii_copytobuf((u_short *)state->cmd,
513 			(volatile u_short *)state->dmaAddr[0], state->cmdlen);
514 		sii_StartDMA(regs, state->dmaCurPhase = SII_CMD_PHASE,
515 			state->dmaAddr[0], state->dmalen = scsicmd->cmdlen);
516 
517 		/* wait a little while for DMA to finish */
518 		SII_WAIT_UNTIL(status, regs->dstat, status & (SII_CI | SII_DI),
519 			SII_WAIT_COUNT, retval);
520 #ifdef DEBUG
521 		if (sii_debug > 2)
522 			printf("sii_StartCmd: ds %x, cnt %d\n", status, retval);
523 #endif
524 		if (status & (SII_CI | SII_DI))
525 			sii_DoIntr(sc, status);
526 #ifdef DEBUG
527 		if (sii_debug > 2)
528 			printf("sii_StartCmd: DONE ds %x\n", regs->dstat);
529 #endif
530 		return;
531 	}
532 
533 	/*
534 	 * Another device may have selected us; in which case,
535 	 * this command will be restarted later.
536 	 */
537 	if (status & (SII_CI | SII_DI)) {
538 		sii_DoIntr(sc, regs->dstat);
539 		return;
540 	}
541 
542 	/*
543 	 * Disconnect if selection command still in progress.
544 	 */
545 	if (status & SII_SIP) {
546 		error = ENXIO;	/* device didn't respond */
547 		regs->comm = SII_DISCON;
548 		wbflush();
549 		SII_WAIT_UNTIL(status, regs->cstat,
550 			!(status & (SII_CON | SII_SIP)),
551 			SII_WAIT_COUNT, retval);
552 	} else
553 		error = EBUSY;	/* couldn't get the bus */
554 #ifdef DEBUG
555 	if (sii_debug > 1)
556 		printf("sii_StartCmd: Couldn't select target %d error %d\n",
557 			target, error);
558 #endif
559 	sc->sc_target = -1;
560 	regs->cstat = 0xffff;
561 	regs->dstat = 0xffff;
562 	regs->comm = 0;
563 	wbflush();
564 	sii_CmdDone(sc, target, error);
565 }
566 
567 /*
568  * Process interrupt conditions.
569  */
570 static void
571 sii_DoIntr(sc, dstat)
572 	struct siisoftc *sc;
573 	u_int dstat;
574 {
575 	SIIRegs *regs = sc->sc_regs;
576 	State *state;
577 	u_int cstat;
578 	int i, msg;
579 	u_int comm;
580 
581 again:
582 	comm = regs->comm;
583 
584 #ifdef DEBUG
585 	if (sii_debug > 3)
586 		printf("sii_DoIntr: cs %x, ds %x cm %x ",
587 			regs->cstat, dstat, comm);
588 	sii_logp->target = sc->sc_target;
589 	sii_logp->cstat = regs->cstat;
590 	sii_logp->dstat = dstat;
591 	sii_logp->comm = comm;
592 	sii_logp->msg = -1;
593 	if (sc->sc_target >= 0) {
594 		sii_logp->rlen = sc->sc_st[sc->sc_target].buflen;
595 		sii_logp->dlen = sc->sc_st[sc->sc_target].dmalen;
596 	} else {
597 		sii_logp->rlen = 0;
598 		sii_logp->dlen = 0;
599 	}
600 	if (++sii_logp >= &sii_log[NLOG])
601 		sii_logp = sii_log;
602 #endif
603 
604 	regs->dstat = dstat;	/* acknowledge everything */
605 	wbflush();
606 
607 	if (dstat & SII_CI) {
608 		/* deglitch cstat register */
609 		msg = regs->cstat;
610 		while (msg != (cstat = regs->cstat))
611 			msg = cstat;
612 		regs->cstat = cstat;	/* acknowledge everything */
613 		wbflush();
614 #ifdef DEBUG
615 		if (sii_logp > sii_log)
616 			sii_logp[-1].cstat = cstat;
617 		else
618 			sii_log[NLOG - 1].cstat = cstat;
619 #endif
620 
621 		/* check for a BUS RESET */
622 		if (cstat & SII_RST) {
623 			printf("%s: SCSI bus reset!!\n", sc->sc_dev.dv_xname);
624 			/* need to flush disconnected commands */
625 			for (i = 0; i < SII_NCMD; i++) {
626 				if (!sc->sc_cmd[i])
627 					continue;
628 				sii_CmdDone(sc, i, EIO);
629 			}
630 			/* rearbitrate synchronous offset */
631 			for (i = 0; i < SII_NCMD; i++)
632 				sc->sc_st[i].dmaReqAck = 0;
633 			sc->sc_target = -1;
634 			return;
635 		}
636 
637 #ifdef notdef
638 		/*
639 		 * Check for a BUS ERROR.
640 		 * According to DEC, this feature doesn't really work
641 		 * and to just clear the bit if it's set.
642 		 */
643 		if (cstat & SII_BER) {
644 			regs->cstat = SII_BER;
645 			wbflush();
646 		}
647 #endif
648 
649 		/* check for state change */
650 		if (cstat & SII_SCH) {
651 			sii_StateChg(sc, cstat);
652 			comm = regs->comm;
653 		}
654 	}
655 
656 	/* check for DMA completion */
657 	if (dstat & SII_DNE) {
658 		u_short *dma;
659 		char *buf;
660 
661 		/*
662 		 * There is a race condition with SII_SCH. There is a short
663 		 * window between the time a SII_SCH is seen after a disconnect
664 		 * and when the SII_SCH is cleared. A reselect can happen
665 		 * in this window and we will clear the SII_SCH without
666 		 * processing the reconnect.
667 		 */
668 		if (sc->sc_target < 0) {
669 			cstat = regs->cstat;
670 			printf("%s: target %d DNE?? dev %d,%d cs %x\n",
671 				sc->sc_dev.dv_xname, sc->sc_target,
672 				regs->slcsr, regs->destat,
673 				cstat); /* XXX */
674 			if (cstat & SII_DST) {
675 				sc->sc_target = regs->destat;
676 				state = &sc->sc_st[sc->sc_target];
677 				state->prevComm = 0;
678 			} else
679 				panic("sc_target 1");
680 		}
681 		state = &sc->sc_st[sc->sc_target];
682 		/* check for a PARITY ERROR */
683 		if (dstat & SII_IPE) {
684 			state->flags |= PARITY_ERR;
685 			printf("%s: Parity error!!\n", sc->sc_dev.dv_xname);
686 			goto abort;
687 		}
688 		/* dmalen = amount left to transfer, i = amount transfered */
689 		i = state->dmalen;
690 		state->dmalen = 0;
691 		state->dmaCurPhase = -1;
692 #ifdef DEBUG
693 		if (sii_debug > 4) {
694 			printf("DNE: amt %d ", i);
695 			if (!(dstat & SII_TCZ))
696 				printf("no TCZ?? (%d) ", regs->dmlotc);
697 		} else if (!(dstat & SII_TCZ)) {
698 			printf("%s: device %d: no TCZ?? (%d)\n",
699 				sc->sc_dev.dv_xname, sc->sc_target, regs->dmlotc);
700 			sii_DumpLog(); /* XXX */
701 		}
702 #endif
703 		switch (comm & SII_PHASE_MSK) {
704 		case SII_CMD_PHASE:
705 			state->cmdlen -= i;
706 			break;
707 
708 		case SII_DATA_IN_PHASE:
709 			/* check for more data for the same phase */
710 			dma = state->dmaAddr[state->dmaBufIndex];
711 			buf = state->buf;
712 			state->buf += i;
713 			state->buflen -= i;
714 			if (state->buflen > 0 && !(dstat & SII_MIS)) {
715 				int len;
716 
717 				/* start reading next chunk */
718 				len = state->buflen;
719 				if (len > SII_MAX_DMA_XFER_LENGTH)
720 					len = SII_MAX_DMA_XFER_LENGTH;
721 				state->dmaBufIndex = !state->dmaBufIndex;
722 				sii_StartDMA(regs,
723 					state->dmaCurPhase = SII_DATA_IN_PHASE,
724 					state->dmaAddr[state->dmaBufIndex],
725 					state->dmaCnt = state->dmalen = len);
726 				dstat &= ~(SII_IBF | SII_TBE);
727 			}
728 			/* copy in the data */
729 			sc->sii_copyfrombuf((volatile u_short *)dma, buf, i);
730 			break;
731 
732 		case SII_DATA_OUT_PHASE:
733 			state->dmaBufIndex = !state->dmaBufIndex;
734 			state->buf += i;
735 			state->buflen -= i;
736 
737 			/* check for more data for the same phase */
738 			if (state->buflen <= 0 || (dstat & SII_MIS))
739 				break;
740 
741 			/* start next chunk */
742 			i = state->buflen;
743 			if (i > SII_MAX_DMA_XFER_LENGTH) {
744 				sii_StartDMA(regs, state->dmaCurPhase =
745 					SII_DATA_OUT_PHASE,
746 					state->dmaAddr[state->dmaBufIndex],
747 					state->dmaCnt = state->dmalen =
748 					SII_MAX_DMA_XFER_LENGTH);
749 				/* prepare for next chunk */
750 				i -= SII_MAX_DMA_XFER_LENGTH;
751 				if (i > SII_MAX_DMA_XFER_LENGTH)
752 					i = SII_MAX_DMA_XFER_LENGTH;
753 				sc->sii_copytobuf((u_short *)(state->buf +
754 					SII_MAX_DMA_XFER_LENGTH),
755 					(volatile u_short *)
756 					state->dmaAddr[!state->dmaBufIndex], i);
757 			} else {
758 				sii_StartDMA(regs, state->dmaCurPhase =
759 					SII_DATA_OUT_PHASE,
760 					state->dmaAddr[state->dmaBufIndex],
761 					state->dmaCnt = state->dmalen = i);
762 			}
763 			dstat &= ~(SII_IBF | SII_TBE);
764 		}
765 	}
766 
767 	/* check for phase change or another MsgIn/Out */
768 	if (dstat & (SII_MIS | SII_IBF | SII_TBE)) {
769 		/*
770 		 * There is a race condition with SII_SCH. There is a short
771 		 * window between the time a SII_SCH is seen after a disconnect
772 		 * and when the SII_SCH is cleared. A reselect can happen
773 		 * in this window and we will clear the SII_SCH without
774 		 * processing the reconnect.
775 		 */
776 		if (sc->sc_target < 0) {
777 			cstat = regs->cstat;
778 			printf("%s: target %d MIS?? dev %d,%d cs %x ds %x\n",
779 				sc->sc_dev.dv_xname, sc->sc_target,
780 				regs->slcsr, regs->destat,
781 				cstat, dstat); /* XXX */
782 			if (cstat & SII_DST) {
783 				sc->sc_target = regs->destat;
784 				state = &sc->sc_st[sc->sc_target];
785 				state->prevComm = 0;
786 			} else {
787 #ifdef DEBUG
788 				sii_DumpLog();
789 #endif
790 				panic("sc_target 2");
791 			}
792 		}
793 		state = &sc->sc_st[sc->sc_target];
794 		switch (dstat & SII_PHASE_MSK) {
795 		case SII_CMD_PHASE:
796 			if (state->dmaPrevPhase >= 0) {
797 				/* restart DMA after disconnect/reconnect */
798 				if (state->dmaPrevPhase != SII_CMD_PHASE) {
799 					printf("%s: device %d: DMA reselect phase doesn't match\n",
800 						sc->sc_dev.dv_xname, sc->sc_target);
801 					goto abort;
802 				}
803 				state->dmaCurPhase = SII_CMD_PHASE;
804 				state->dmaPrevPhase = -1;
805 				regs->dmaddrl = state->dmaAddrL;
806 				regs->dmaddrh = state->dmaAddrH;
807 				regs->dmlotc = state->dmaCnt;
808 				if (state->dmaCnt & 1)
809 					regs->dmabyte = state->dmaByte;
810 				regs->comm = SII_DMA | SII_INXFER |
811 					(comm & SII_STATE_MSK) | SII_CMD_PHASE;
812 				wbflush();
813 #ifdef DEBUG
814 				if (sii_debug > 4)
815 					printf("Cmd dcnt %d dadr %x ",
816 						state->dmaCnt,
817 						(state->dmaAddrH << 16) |
818 							state->dmaAddrL);
819 #endif
820 			} else {
821 				/* send command data */
822 				i = state->cmdlen;
823 				if (i == 0) {
824 					printf("%s: device %d: cmd count exceeded\n",
825 						sc->sc_dev.dv_xname, sc->sc_target);
826 					goto abort;
827 				}
828 				sc->sii_copytobuf((u_short *)state->cmd,
829 					(volatile u_short *)state->dmaAddr[0],
830 					i);
831 				sii_StartDMA(regs, state->dmaCurPhase =
832 					SII_CMD_PHASE, state->dmaAddr[0],
833 					state->dmaCnt = state->dmalen = i);
834 			}
835 			/* wait a short time for XFER complete */
836 			SII_WAIT_UNTIL(dstat, regs->dstat,
837 				dstat & (SII_CI | SII_DI), SII_WAIT_COUNT, i);
838 			if (dstat & (SII_CI | SII_DI)) {
839 #ifdef DEBUG
840 				if (sii_debug > 4)
841 					printf("cnt %d\n", i);
842 				else if (sii_debug > 0)
843 					printf("sii_DoIntr: cmd wait ds %x cnt %d\n",
844 						dstat, i);
845 #endif
846 				goto again;
847 			}
848 			break;
849 
850 		case SII_DATA_IN_PHASE:
851 		case SII_DATA_OUT_PHASE:
852 			if (state->cmdlen > 0) {
853 				printf("%s: device %d: cmd %x: command data not all sent (%d) 1\n",
854 					sc->sc_dev.dv_xname, sc->sc_target,
855 					sc->sc_cmd[sc->sc_target]->cmd[0],
856 					state->cmdlen);
857 				state->cmdlen = 0;
858 #ifdef DEBUG
859 				sii_DumpLog();
860 #endif
861 			}
862 			if (state->dmaPrevPhase >= 0) {
863 				/* restart DMA after disconnect/reconnect */
864 				if (state->dmaPrevPhase !=
865 				    (dstat & SII_PHASE_MSK)) {
866 					printf("%s: device %d: DMA reselect phase doesn't match\n",
867 						sc->sc_dev.dv_xname, sc->sc_target);
868 					goto abort;
869 				}
870 				state->dmaCurPhase = state->dmaPrevPhase;
871 				state->dmaPrevPhase = -1;
872 				regs->dmaddrl = state->dmaAddrL;
873 				regs->dmaddrh = state->dmaAddrH;
874 				regs->dmlotc = state->dmaCnt;
875 				if (state->dmaCnt & 1)
876 					regs->dmabyte = state->dmaByte;
877 				regs->comm = SII_DMA | SII_INXFER |
878 					(comm & SII_STATE_MSK) |
879 					state->dmaCurPhase;
880 				wbflush();
881 #ifdef DEBUG
882 				if (sii_debug > 4)
883 					printf("Data %d dcnt %d dadr %x ",
884 						state->dmaDataPhase,
885 						state->dmaCnt,
886 						(state->dmaAddrH << 16) |
887 							state->dmaAddrL);
888 #endif
889 				break;
890 			}
891 #ifdef DEBUG
892 			if (sii_debug > 4) {
893 				printf("Data %d ", state->dmaDataPhase);
894 				if (sii_debug > 5)
895 					printf("\n");
896 			}
897 #endif
898 			i = state->buflen;
899 			if (i == 0) {
900 				printf("%s: device %d: data count exceeded\n",
901 					sc->sc_dev.dv_xname, sc->sc_target);
902 				goto abort;
903 			}
904 			if (i > SII_MAX_DMA_XFER_LENGTH)
905 				i = SII_MAX_DMA_XFER_LENGTH;
906 			if ((dstat & SII_PHASE_MSK) == SII_DATA_IN_PHASE) {
907 				sii_StartDMA(regs,
908 					state->dmaCurPhase = SII_DATA_IN_PHASE,
909 					state->dmaAddr[state->dmaBufIndex],
910 					state->dmaCnt = state->dmalen = i);
911 				break;
912 			}
913 			/* start first chunk */
914 			if (state->flags & FIRST_DMA) {
915 				state->flags &= ~FIRST_DMA;
916 				sc->sii_copytobuf((u_short *)state->buf,
917 					(volatile u_short *)
918 					state->dmaAddr[state->dmaBufIndex], i);
919 			}
920 			sii_StartDMA(regs,
921 				state->dmaCurPhase = SII_DATA_OUT_PHASE,
922 				state->dmaAddr[state->dmaBufIndex],
923 				state->dmaCnt = state->dmalen = i);
924 			i = state->buflen - SII_MAX_DMA_XFER_LENGTH;
925 			if (i > 0) {
926 				/* prepare for next chunk */
927 				if (i > SII_MAX_DMA_XFER_LENGTH)
928 					i = SII_MAX_DMA_XFER_LENGTH;
929 				sc->sii_copytobuf((u_short *)(state->buf +
930 					SII_MAX_DMA_XFER_LENGTH),
931 					(volatile u_short *)
932 					state->dmaAddr[!state->dmaBufIndex], i);
933 			}
934 			break;
935 
936 		case SII_STATUS_PHASE:
937 			if (state->cmdlen > 0) {
938 				printf("%s: device %d: cmd %x: command data not all sent (%d) 2\n",
939 					sc->sc_dev.dv_xname, sc->sc_target,
940 					sc->sc_cmd[sc->sc_target]->cmd[0],
941 					state->cmdlen);
942 				state->cmdlen = 0;
943 #ifdef DEBUG
944 				sii_DumpLog();
945 #endif
946 			}
947 
948 			/* read amount transfered if DMA didn't finish */
949 			if (state->dmalen > 0) {
950 				i = state->dmalen - regs->dmlotc;
951 				state->dmalen = 0;
952 				state->dmaCurPhase = -1;
953 				regs->dmlotc = 0;
954 				regs->comm = comm &
955 					(SII_STATE_MSK | SII_PHASE_MSK);
956 				wbflush();
957 				regs->dstat = SII_DNE;
958 				wbflush();
959 #ifdef DEBUG
960 				if (sii_debug > 4)
961 					printf("DMA amt %d ", i);
962 #endif
963 				switch (comm & SII_PHASE_MSK) {
964 				case SII_DATA_IN_PHASE:
965 					/* copy in the data */
966 					sc->sii_copyfrombuf((volatile u_short*)
967 					    state->dmaAddr[state->dmaBufIndex],
968 					    state->buf, i);
969 
970 				case SII_CMD_PHASE:
971 				case SII_DATA_OUT_PHASE:
972 					state->buflen -= i;
973 				}
974 			}
975 
976 			/* read a one byte status message */
977 			state->statusByte = msg =
978 				sii_GetByte(regs, SII_STATUS_PHASE, 1);
979 			if (msg < 0) {
980 				dstat = regs->dstat;
981 				goto again;
982 			}
983 #ifdef DEBUG
984 			if (sii_debug > 4)
985 				printf("Status %x ", msg);
986 			if (sii_logp > sii_log)
987 				sii_logp[-1].msg = msg;
988 			else
989 				sii_log[NLOG - 1].msg = msg;
990 #endif
991 
992 			/* do a quick wait for COMMAND_COMPLETE */
993 			SII_WAIT_UNTIL(dstat, regs->dstat,
994 				dstat & (SII_CI | SII_DI), SII_WAIT_COUNT, i);
995 			if (dstat & (SII_CI | SII_DI)) {
996 #ifdef DEBUG
997 				if (sii_debug > 4)
998 					printf("cnt2 %d\n", i);
999 #endif
1000 				goto again;
1001 			}
1002 			break;
1003 
1004 		case SII_MSG_IN_PHASE:
1005 			/*
1006 			 * Save DMA state if DMA didn't finish.
1007 			 * Be careful not to save state again after reconnect
1008 			 * and see RESTORE_POINTER message.
1009 			 * Note that the SII DMA address is not incremented
1010 			 * as DMA proceeds.
1011 			 */
1012 			if (state->dmaCurPhase >= 0) {
1013 				/* save DMA registers */
1014 				state->dmaPrevPhase = state->dmaCurPhase;
1015 				state->dmaCurPhase = -1;
1016 				if (dstat & SII_OBB)
1017 					state->dmaByte = regs->dmabyte;
1018 				i = regs->dmlotc;
1019 				if (i != 0)
1020 					i = state->dmaCnt - i;
1021 				/* note: no carry from dmaddrl to dmaddrh */
1022 				state->dmaAddrL = regs->dmaddrl + i;
1023 				state->dmaAddrH = regs->dmaddrh;
1024 				state->dmaCnt = regs->dmlotc;
1025 				if (state->dmaCnt == 0)
1026 					state->dmaCnt = SII_MAX_DMA_XFER_LENGTH;
1027 				regs->comm = comm &
1028 					(SII_STATE_MSK | SII_PHASE_MSK);
1029 				wbflush();
1030 				regs->dstat = SII_DNE;
1031 				wbflush();
1032 #ifdef DEBUG
1033 				if (sii_debug > 4) {
1034 					printf("SavP dcnt %d dadr %x ",
1035 						state->dmaCnt,
1036 						(state->dmaAddrH << 16) |
1037 						state->dmaAddrL);
1038 					if (((dstat & SII_OBB) != 0) ^
1039 					    (state->dmaCnt & 1))
1040 						printf("OBB??? ");
1041 				} else if (sii_debug > 0) {
1042 					if (((dstat & SII_OBB) != 0) ^
1043 					    (state->dmaCnt & 1)) {
1044 						printf("sii_DoIntr: OBB??? ds %x cnt %d\n",
1045 							dstat, state->dmaCnt);
1046 						sii_DumpLog();
1047 					}
1048 				}
1049 #endif
1050 			}
1051 
1052 			/* read a one byte message */
1053 			msg = sii_GetByte(regs, SII_MSG_IN_PHASE, 0);
1054 			if (msg < 0) {
1055 				dstat = regs->dstat;
1056 				goto again;
1057 			}
1058 #ifdef DEBUG
1059 			if (sii_debug > 4)
1060 				printf("MsgIn %x ", msg);
1061 			if (sii_logp > sii_log)
1062 				sii_logp[-1].msg = msg;
1063 			else
1064 				sii_log[NLOG - 1].msg = msg;
1065 #endif
1066 
1067 			/* process message */
1068 			switch (msg) {
1069 			case MSG_CMDCOMPLETE:
1070 				/* acknowledge last byte */
1071 				regs->comm = SII_INXFER | SII_MSG_IN_PHASE |
1072 					(comm & SII_STATE_MSK);
1073 				SII_WAIT_UNTIL(dstat, regs->dstat,
1074 					dstat & SII_DNE, SII_WAIT_COUNT, i);
1075 				regs->dstat = SII_DNE;
1076 				wbflush();
1077 				msg = sc->sc_target;
1078 				sc->sc_target = -1;
1079 				/*
1080 				 * Wait a short time for disconnect.
1081 				 * Don't be fooled if SII_BER happens first.
1082 				 * Note: a reselect may happen here.
1083 				 */
1084 				SII_WAIT_UNTIL(cstat, regs->cstat,
1085 					cstat & (SII_RST | SII_SCH),
1086 					SII_WAIT_COUNT, i);
1087 				if ((cstat & (SII_RST | SII_SCH |
1088 				    SII_STATE_MSK)) == SII_SCH) {
1089 					regs->cstat = SII_SCH | SII_BER;
1090 					regs->comm = 0;
1091 					wbflush();
1092 					/*
1093 					 * Double check that we didn't miss a
1094 					 * state change between seeing it and
1095 					 * clearing the SII_SCH bit.
1096 					 */
1097 					i = regs->cstat;
1098 					if (!(i & SII_SCH) &&
1099 					    (i & SII_STATE_MSK) !=
1100 					    (cstat & SII_STATE_MSK))
1101 						sii_StateChg(sc, i);
1102 				}
1103 #ifdef DEBUG
1104 				if (sii_debug > 4)
1105 					printf("cs %x\n", cstat);
1106 #endif
1107 				sii_CmdDone(sc, msg, 0);
1108 				break;
1109 
1110 			case MSG_EXTENDED:
1111 				/* acknowledge last byte */
1112 				regs->comm = SII_INXFER | SII_MSG_IN_PHASE |
1113 					(comm & SII_STATE_MSK);
1114 				SII_WAIT_UNTIL(dstat, regs->dstat,
1115 					dstat & SII_DNE, SII_WAIT_COUNT, i);
1116 				regs->dstat = SII_DNE;
1117 				wbflush();
1118 				/* read the message length */
1119 				msg = sii_GetByte(regs, SII_MSG_IN_PHASE, 1);
1120 				if (msg < 0) {
1121 					dstat = regs->dstat;
1122 					goto again;
1123 				}
1124 				sii_buf[1] = msg;	/* message length */
1125 				if (msg == 0)
1126 					msg = 256;
1127 				/*
1128 				 * We read and acknowlege all the bytes
1129 				 * except the last so we can assert ATN
1130 				 * if needed before acknowledging the last.
1131 				 */
1132 				for (i = 0; i < msg; i++) {
1133 					dstat = sii_GetByte(regs,
1134 						SII_MSG_IN_PHASE, i < msg - 1);
1135 					if ((int)dstat < 0) {
1136 						dstat = regs->dstat;
1137 						goto again;
1138 					}
1139 					sii_buf[i + 2] = dstat;
1140 				}
1141 
1142 				switch (sii_buf[2]) {
1143 				case MSG_EXT_MODIFY_DATA_PTR:
1144 					/* acknowledge last byte */
1145 					regs->comm = SII_INXFER |
1146 						SII_MSG_IN_PHASE |
1147 						(comm & SII_STATE_MSK);
1148 					SII_WAIT_UNTIL(dstat, regs->dstat,
1149 						dstat & SII_DNE,
1150 						SII_WAIT_COUNT, i);
1151 					regs->dstat = SII_DNE;
1152 					wbflush();
1153 					i = (sii_buf[3] << 24) |
1154 						(sii_buf[4] << 16) |
1155 						(sii_buf[5] << 8) |
1156 						sii_buf[6];
1157 					if (state->dmaPrevPhase >= 0) {
1158 						state->dmaAddrL += i;
1159 						state->dmaCnt -= i;
1160 					}
1161 					break;
1162 
1163 				case MSG_EXT_SDTR_LEN:
1164 					/*
1165 					 * Acknowledge last byte and
1166 					 * signal a request for MSG_OUT.
1167 					 */
1168 					regs->comm = SII_INXFER | SII_ATN |
1169 						SII_MSG_IN_PHASE |
1170 						(comm & SII_STATE_MSK);
1171 					SII_WAIT_UNTIL(dstat, regs->dstat,
1172 						dstat & SII_DNE,
1173 						SII_WAIT_COUNT, i);
1174 					regs->dstat = SII_DNE;
1175 					wbflush();
1176 					sii_DoSync(regs, state);
1177 					break;
1178 
1179 				default:
1180 				reject:
1181 					/*
1182 					 * Acknowledge last byte and
1183 					 * signal a request for MSG_OUT.
1184 					 */
1185 					regs->comm = SII_INXFER | SII_ATN |
1186 						SII_MSG_IN_PHASE |
1187 						(comm & SII_STATE_MSK);
1188 					SII_WAIT_UNTIL(dstat, regs->dstat,
1189 						dstat & SII_DNE,
1190 						SII_WAIT_COUNT, i);
1191 					regs->dstat = SII_DNE;
1192 					wbflush();
1193 
1194 					/* wait for MSG_OUT phase */
1195 					SII_WAIT_UNTIL(dstat, regs->dstat,
1196 						dstat & SII_TBE,
1197 						SII_WAIT_COUNT, i);
1198 
1199 					/* send a reject message */
1200 					regs->data = MSG_MESSAGE_REJECT;
1201 					regs->comm = SII_INXFER |
1202 						(regs->cstat & SII_STATE_MSK) |
1203 						SII_MSG_OUT_PHASE;
1204 					SII_WAIT_UNTIL(dstat, regs->dstat,
1205 						dstat & SII_DNE,
1206 						SII_WAIT_COUNT, i);
1207 					regs->dstat = SII_DNE;
1208 					wbflush();
1209 				}
1210 				break;
1211 
1212 			case MSG_SAVEDATAPOINTER:
1213 			case MSG_RESTOREPOINTERS:
1214 				/* acknowledge last byte */
1215 				regs->comm = SII_INXFER | SII_MSG_IN_PHASE |
1216 					(comm & SII_STATE_MSK);
1217 				SII_WAIT_UNTIL(dstat, regs->dstat,
1218 					dstat & SII_DNE, SII_WAIT_COUNT, i);
1219 				regs->dstat = SII_DNE;
1220 				wbflush();
1221 				/* wait a short time for another msg */
1222 				SII_WAIT_UNTIL(dstat, regs->dstat,
1223 					dstat & (SII_CI | SII_DI),
1224 					SII_WAIT_COUNT, i);
1225 				if (dstat & (SII_CI | SII_DI)) {
1226 #ifdef DEBUG
1227 					if (sii_debug > 4)
1228 						printf("cnt %d\n", i);
1229 #endif
1230 					goto again;
1231 				}
1232 				break;
1233 
1234 			case MSG_DISCONNECT:
1235 				/* acknowledge last byte */
1236 				regs->comm = SII_INXFER | SII_MSG_IN_PHASE |
1237 					(comm & SII_STATE_MSK);
1238 				SII_WAIT_UNTIL(dstat, regs->dstat,
1239 					dstat & SII_DNE, SII_WAIT_COUNT, i);
1240 				regs->dstat = SII_DNE;
1241 				wbflush();
1242 				state->prevComm = comm;
1243 #ifdef DEBUG
1244 				if (sii_debug > 4)
1245 					printf("disconn %d ", sc->sc_target);
1246 #endif
1247 				/*
1248 				 * Wait a short time for disconnect.
1249 				 * Don't be fooled if SII_BER happens first.
1250 				 * Note: a reselect may happen here.
1251 				 */
1252 				SII_WAIT_UNTIL(cstat, regs->cstat,
1253 					cstat & (SII_RST | SII_SCH),
1254 					SII_WAIT_COUNT, i);
1255 				if ((cstat & (SII_RST | SII_SCH |
1256 				    SII_STATE_MSK)) != SII_SCH) {
1257 #ifdef DEBUG
1258 					if (sii_debug > 4)
1259 						printf("cnt %d\n", i);
1260 #endif
1261 					dstat = regs->dstat;
1262 					goto again;
1263 				}
1264 				regs->cstat = SII_SCH | SII_BER;
1265 				regs->comm = 0;
1266 				wbflush();
1267 				sc->sc_target = -1;
1268 				/*
1269 				 * Double check that we didn't miss a state
1270 				 * change between seeing it and clearing
1271 				 * the SII_SCH bit.
1272 				 */
1273 				i = regs->cstat;
1274 				if (!(i & SII_SCH) && (i & SII_STATE_MSK) !=
1275 				    (cstat & SII_STATE_MSK))
1276 					sii_StateChg(sc, i);
1277 				break;
1278 
1279 			case MSG_MESSAGE_REJECT:
1280 				/* acknowledge last byte */
1281 				regs->comm = SII_INXFER | SII_MSG_IN_PHASE |
1282 					(comm & SII_STATE_MSK);
1283 				SII_WAIT_UNTIL(dstat, regs->dstat,
1284 					dstat & SII_DNE, SII_WAIT_COUNT, i);
1285 				regs->dstat = SII_DNE;
1286 				wbflush();
1287 				printf("%s: device %d: message reject.\n",
1288 					sc->sc_dev.dv_xname, sc->sc_target);
1289 				break;
1290 
1291 			default:
1292 				if (!(msg & MSG_IDENTIFYFLAG)) {
1293 					printf("%s: device %d: couldn't handle "
1294 					    "message 0x%x... rejecting.\n",
1295 					    sc->sc_dev.dv_xname, sc->sc_target,
1296 					    msg);
1297 #ifdef DEBUG
1298 					sii_DumpLog();
1299 #endif
1300 					goto reject;
1301 				}
1302 				/* acknowledge last byte */
1303 				regs->comm = SII_INXFER | SII_MSG_IN_PHASE |
1304 					(comm & SII_STATE_MSK);
1305 				SII_WAIT_UNTIL(dstat, regs->dstat,
1306 					dstat & SII_DNE, SII_WAIT_COUNT, i);
1307 				regs->dstat = SII_DNE;
1308 				wbflush();
1309 				/* may want to check LUN some day */
1310 				/* wait a short time for another msg */
1311 				SII_WAIT_UNTIL(dstat, regs->dstat,
1312 					dstat & (SII_CI | SII_DI),
1313 					SII_WAIT_COUNT, i);
1314 				if (dstat & (SII_CI | SII_DI)) {
1315 #ifdef DEBUG
1316 					if (sii_debug > 4)
1317 						printf("cnt %d\n", i);
1318 #endif
1319 					goto again;
1320 				}
1321 			}
1322 			break;
1323 
1324 		case SII_MSG_OUT_PHASE:
1325 #ifdef DEBUG
1326 			if (sii_debug > 4)
1327 				printf("MsgOut\n");
1328 #endif
1329 			printf("MsgOut %x\n", state->flags); /* XXX */
1330 
1331 			/*
1332 			 * Check for parity error.
1333 			 * Hardware will automatically set ATN
1334 			 * to request the device for a MSG_OUT phase.
1335 			 */
1336 			if (state->flags & PARITY_ERR) {
1337 				state->flags &= ~PARITY_ERR;
1338 				regs->data = MSG_PARITY_ERROR;
1339 			} else
1340 				regs->data = MSG_NOOP;
1341 			regs->comm = SII_INXFER | (comm & SII_STATE_MSK) |
1342 				SII_MSG_OUT_PHASE;
1343 			wbflush();
1344 
1345 			/* wait a short time for XFER complete */
1346 			SII_WAIT_UNTIL(dstat, regs->dstat, dstat & SII_DNE,
1347 				SII_WAIT_COUNT, i);
1348 #ifdef DEBUG
1349 			if (sii_debug > 4)
1350 				printf("ds %x i %d\n", dstat, i);
1351 #endif
1352 			/* just clear the DNE bit and check errors later */
1353 			if (dstat & SII_DNE) {
1354 				regs->dstat = SII_DNE;
1355 				wbflush();
1356 			}
1357 			break;
1358 
1359 		default:
1360 			printf("%s: Couldn't handle phase %d... ignoring.\n",
1361 				   sc->sc_dev.dv_xname, dstat & SII_PHASE_MSK);
1362 		}
1363 	}
1364 
1365 #ifdef DEBUG
1366 	if (sii_debug > 3)
1367 		printf("\n");
1368 #endif
1369 	/*
1370 	 * Check to make sure we won't be interrupted again.
1371 	 * Deglitch dstat register.
1372 	 */
1373 	msg = regs->dstat;
1374 	while (msg != (dstat = regs->dstat))
1375 		msg = dstat;
1376 	if (dstat & (SII_CI | SII_DI))
1377 		goto again;
1378 
1379 	if (sc->sc_target < 0) {
1380 		/* look for another device that is ready */
1381 		for (i = 0; i < SII_NCMD; i++) {
1382 			/* don't restart a disconnected command */
1383 			if (!sc->sc_cmd[i] || sc->sc_st[i].prevComm)
1384 				continue;
1385 			sii_StartCmd(sc, i);
1386 			break;
1387 		}
1388 	}
1389 	return;
1390 
1391 abort:
1392 	/* jump here to abort the current command */
1393 	printf("%s: device %d: current command terminated\n",
1394 		sc->sc_dev.dv_xname, sc->sc_target);
1395 #ifdef DEBUG
1396 	sii_DumpLog();
1397 #endif
1398 
1399 	if ((cstat = regs->cstat) & SII_CON) {
1400 		/* try to send an abort msg for awhile */
1401 		regs->dstat = SII_DNE;
1402 		regs->data = MSG_ABORT;
1403 		regs->comm = SII_INXFER | SII_ATN | (cstat & SII_STATE_MSK) |
1404 			SII_MSG_OUT_PHASE;
1405 		wbflush();
1406 		SII_WAIT_UNTIL(dstat, regs->dstat,
1407 			(dstat & (SII_DNE | SII_PHASE_MSK)) ==
1408 			(SII_DNE | SII_MSG_OUT_PHASE),
1409 			2 * SII_WAIT_COUNT, i);
1410 #ifdef DEBUG
1411 		if (sii_debug > 0)
1412 			printf("Abort: cs %x ds %x i %d\n", cstat, dstat, i);
1413 #endif
1414 		if ((dstat & (SII_DNE | SII_PHASE_MSK)) ==
1415 		    (SII_DNE | SII_MSG_OUT_PHASE)) {
1416 			/* disconnect if command in progress */
1417 			regs->comm = SII_DISCON;
1418 			wbflush();
1419 			SII_WAIT_UNTIL(cstat, regs->cstat,
1420 				!(cstat & SII_CON), SII_WAIT_COUNT, i);
1421 		}
1422 	} else {
1423 #ifdef DEBUG
1424 		if (sii_debug > 0)
1425 			printf("Abort: cs %x\n", cstat);
1426 #endif
1427 	}
1428 	regs->cstat = 0xffff;
1429 	regs->dstat = 0xffff;
1430 	regs->comm = 0;
1431 	wbflush();
1432 
1433 	i = sc->sc_target;
1434 	sc->sc_target = -1;
1435 	sii_CmdDone(sc, i, EIO);
1436 #ifdef DEBUG
1437 	if (sii_debug > 4)
1438 		printf("sii_DoIntr: after CmdDone target %d\n", sc->sc_target);
1439 #endif
1440 }
1441 
1442 static void
1443 sii_StateChg(sc, cstat)
1444 	struct siisoftc *sc;
1445 	u_int cstat;
1446 {
1447 	SIIRegs *regs = sc->sc_regs;
1448 	State *state;
1449 	int i;
1450 
1451 #ifdef DEBUG
1452 	if (sii_debug > 4)
1453 		printf("SCH: ");
1454 #endif
1455 
1456 	switch (cstat & SII_STATE_MSK) {
1457 	case 0:
1458 		/* disconnect */
1459 		i = sc->sc_target;
1460 		sc->sc_target = -1;
1461 #ifdef DEBUG
1462 		if (sii_debug > 4)
1463 			printf("disconn %d ", i);
1464 #endif
1465 		if (i >= 0 && !sc->sc_st[i].prevComm) {
1466 			printf("%s: device %d: spurrious disconnect (%d)\n",
1467 				sc->sc_dev.dv_xname, i, regs->slcsr);
1468 			sc->sc_st[i].prevComm = 0;
1469 		}
1470 		break;
1471 
1472 	case SII_CON:
1473 		/* connected as initiator */
1474 		i = regs->slcsr;
1475 		if (sc->sc_target == i)
1476 			break;
1477 		printf("%s: device %d: connect to device %d??\n",
1478 			sc->sc_dev.dv_xname, sc->sc_target, i);
1479 		sc->sc_target = i;
1480 		break;
1481 
1482 	case SII_DST:
1483 		/*
1484 		 * Wait for CON to become valid,
1485 		 * chip is slow sometimes.
1486 		 */
1487 		SII_WAIT_UNTIL(cstat, regs->cstat,
1488 			cstat & SII_CON, SII_WAIT_COUNT, i);
1489 		if (!(cstat & SII_CON))
1490 			panic("sii resel");
1491 		/* FALLTHROUGH */
1492 
1493 	case SII_CON | SII_DST:
1494 		/*
1495 		 * Its a reselection. Save the ID and wait for
1496 		 * interrupts to tell us what to do next
1497 		 * (should be MSG_IN of IDENTIFY).
1498 		 * NOTE: sc_target may be >= 0 if we were in
1499 		 * the process of trying to start a command
1500 		 * and were reselected before the select
1501 		 * command finished.
1502 		 */
1503 		sc->sc_target = i = regs->destat;
1504 		state = &sc->sc_st[i];
1505 		regs->comm = SII_CON | SII_DST | SII_MSG_IN_PHASE;
1506 		regs->dmctrl = state->dmaReqAck;
1507 		wbflush();
1508 		if (!state->prevComm) {
1509 			printf("%s: device %d: spurious reselection\n",
1510 				sc->sc_dev.dv_xname, i);
1511 			break;
1512 		}
1513 		state->prevComm = 0;
1514 #ifdef DEBUG
1515 		if (sii_debug > 4)
1516 			printf("resel %d ", sc->sc_target);
1517 #endif
1518 		break;
1519 
1520 #ifdef notyet
1521 	case SII_DST | SII_TGT:
1522 	case SII_CON | SII_DST | SII_TGT:
1523 		/* connected as target */
1524 		printf("%s: Selected by device %d as target!!\n",
1525 			sc->sc_dev.dv_xname, regs->destat);
1526 		regs->comm = SII_DISCON;
1527 		wbflush();
1528 		SII_WAIT_UNTIL(!(regs->cstat & SII_CON),
1529 			SII_WAIT_COUNT, i);
1530 		regs->cstat = 0xffff;
1531 		regs->dstat = 0xffff;
1532 		regs->comm = 0;
1533 		break;
1534 #endif
1535 
1536 	default:
1537 		printf("%s: Unknown state change (cs %x)!!\n",
1538 			sc->sc_dev.dv_xname, cstat);
1539 #ifdef DEBUG
1540 		sii_DumpLog();
1541 #endif
1542 	}
1543 }
1544 
1545 /*
1546  * Read one byte of data.
1547  * If 'ack' is true, acknowledge the byte.
1548  */
1549 static int
1550 sii_GetByte(regs, phase, ack)
1551 	SIIRegs *regs;
1552 	int phase, ack;
1553 {
1554 	u_int dstat;
1555 	u_int state;
1556 	int i;
1557 	int data;
1558 
1559 	dstat = regs->dstat;
1560 	state = regs->cstat & SII_STATE_MSK;
1561 	i = -1;
1562 	if (!(dstat & SII_IBF) || (dstat & SII_MIS)) {
1563 		regs->comm = state | phase;
1564 		wbflush();
1565 		/* wait a short time for IBF */
1566 		SII_WAIT_UNTIL(dstat, regs->dstat, dstat & SII_IBF,
1567 			SII_WAIT_COUNT, i);
1568 #ifdef DEBUG
1569 		if (!(dstat & SII_IBF))
1570 			printf("status no IBF\n");
1571 #endif
1572 	}
1573 	if (dstat & SII_DNE) { /* XXX */
1574 		printf("sii_GetByte: DNE set 5\n");
1575 #ifdef DEBUG
1576 		sii_DumpLog();
1577 #endif
1578 		regs->dstat = SII_DNE;
1579 	}
1580 	data = regs->data;
1581 	/* check for parity error */
1582 	if (dstat & SII_IPE) {
1583 #ifdef DEBUG
1584 		if (sii_debug > 4)
1585 			printf("cnt0 %d\n", i);
1586 #endif
1587 		printf("sii_GetByte: data %x ?? ds %x cm %x i %d\n",
1588 			data, dstat, regs->comm, i); /* XXX */
1589 		data = -1;
1590 		ack = 1;
1591 	}
1592 
1593 	if (ack) {
1594 		regs->comm = SII_INXFER | state | phase;
1595 		wbflush();
1596 
1597 		/* wait a short time for XFER complete */
1598 		SII_WAIT_UNTIL(dstat, regs->dstat, dstat & SII_DNE,
1599 			SII_WAIT_COUNT, i);
1600 
1601 		/* clear the DNE */
1602 		if (dstat & SII_DNE) {
1603 			regs->dstat = SII_DNE;
1604 			wbflush();
1605 		}
1606 	}
1607 
1608 	return (data);
1609 }
1610 
1611 /*
1612  * Exchange messages to initiate synchronous data transfers.
1613  */
1614 static void
1615 sii_DoSync(regs, state)
1616 	SIIRegs *regs;
1617 	State *state;
1618 {
1619 	u_int dstat, comm;
1620 	int i, j;
1621 	u_int len;
1622 
1623 #ifdef DEBUG
1624 	if (sii_debug)
1625 		printf("sii_DoSync: len %d per %d req/ack %d\n",
1626 			sii_buf[1], sii_buf[3], sii_buf[4]);
1627 #endif
1628 
1629 	/* SII chip can only handle a minimum transfer period of ??? */
1630 	if (sii_buf[3] < 64)
1631 		sii_buf[3] = 64;
1632 	/* SII chip can only handle a maximum REQ/ACK offset of 3 */
1633 	len = sii_buf[4];
1634 	if (len > 3)
1635 		len = 3;
1636 
1637 	sii_buf[0] = MSG_EXTENDED;
1638 	sii_buf[1] = MSG_EXT_SDTR_LEN;
1639 	sii_buf[2] = MSG_EXT_SDTR;
1640 	sii_buf[4] = len;
1641 #if 1
1642 	comm = SII_INXFER | SII_ATN | SII_MSG_OUT_PHASE |
1643 		(regs->cstat & SII_STATE_MSK);
1644 	regs->comm = comm & ~SII_INXFER;
1645 	for (j = 0; j < 5; j++) {
1646 		/* wait for target to request the next byte */
1647 		SII_WAIT_UNTIL(dstat, regs->dstat, dstat & SII_TBE,
1648 			SII_WAIT_COUNT, i);
1649 		if (!(dstat & SII_TBE) ||
1650 		    (dstat & SII_PHASE_MSK) != SII_MSG_OUT_PHASE) {
1651 			printf("sii_DoSync: TBE? ds %x cm %x i %d\n",
1652 				dstat, comm, i); /* XXX */
1653 			return;
1654 		}
1655 
1656 		/* the last message byte should have ATN off */
1657 		if (j == 4)
1658 			comm &= ~SII_ATN;
1659 
1660 		regs->data = sii_buf[j];
1661 		regs->comm = comm;
1662 		wbflush();
1663 
1664 		/* wait a short time for XFER complete */
1665 		SII_WAIT_UNTIL(dstat, regs->dstat, dstat & SII_DNE,
1666 			SII_WAIT_COUNT, i);
1667 
1668 		if (!(dstat & SII_DNE)) {
1669 			printf("sii_DoSync: DNE? ds %x cm %x i %d\n",
1670 				dstat, comm, i); /* XXX */
1671 			return;
1672 		}
1673 
1674 		/* clear the DNE, other errors handled later */
1675 		regs->dstat = SII_DNE;
1676 		wbflush();
1677 	}
1678 #else	/* 0 */
1679 	sc->sii_copytobuf((u_short *)sii_buf,
1680 		     (volatile u_short *)SII_BUF_ADDR(sc), 5);
1681 	printf("sii_DoSync: %x %x %x ds %x\n",
1682 		((volatile u_short *)SII_BUF_ADDR(sc))[0],
1683 		((volatile u_short *)SII_BUF_ADDR(sc))[2],
1684 		((volatile u_short *)SII_BUF_ADDR(sc))[4],
1685 		regs->dstat); /* XXX */
1686 	regs->dmaddrl = (u_short)(SII_BUF_ADDR(sc) >> 1);
1687 	regs->dmaddrh = (u_short)(SII_BUF_ADDR(sc) >> 17) & 03;
1688 	regs->dmlotc = 5;
1689 	regs->comm = SII_DMA | SII_INXFER | SII_ATN |
1690 		(regs->cstat & SII_STATE_MSK) | SII_MSG_OUT_PHASE;
1691 	wbflush();
1692 
1693 	/* wait a short time for XFER complete */
1694 	SII_WAIT_UNTIL(dstat, regs->dstat,
1695 		(dstat & (SII_DNE | SII_TCZ)) == (SII_DNE | SII_TCZ),
1696 		SII_WAIT_COUNT, i);
1697 
1698 	if ((dstat & (SII_DNE | SII_TCZ)) != (SII_DNE | SII_TCZ)) {
1699 		printf("sii_DoSync: ds %x cm %x i %d lotc %d\n",
1700 			dstat, regs->comm, i, regs->dmlotc); /* XXX */
1701 		sii_DumpLog(); /* XXX */
1702 		return;
1703 	}
1704 	/* clear the DNE, other errors handled later */
1705 	regs->dstat = SII_DNE;
1706 	wbflush();
1707 #endif	/* 0 */
1708 
1709 #if 0
1710 	SII_WAIT_UNTIL(dstat, regs->dstat, dstat & (SII_CI | SII_DI),
1711 		SII_WAIT_COUNT, i);
1712 	printf("sii_DoSync: ds %x cm %x i %d lotc %d\n",
1713 		dstat, regs->comm, i, regs->dmlotc); /* XXX */
1714 #endif
1715 
1716 	state->dmaReqAck = len;
1717 }
1718 
1719 /*
1720  * Issue the sequence of commands to the controller to start DMA.
1721  * NOTE: the data buffer should be word-aligned for DMA out.
1722  */
1723 static void
1724 sii_StartDMA(regs, phase, dmaAddr, size)
1725 	SIIRegs *regs;	/* which SII to use */
1726 	int phase;		/* phase to send/receive data */
1727 	u_short *dmaAddr;	/* DMA buffer address */
1728 	int size;		/* # of bytes to transfer */
1729 {
1730 
1731 	if (regs->dstat & SII_DNE) { /* XXX */
1732 		regs->dstat = SII_DNE;
1733 		printf("sii_StartDMA: DNE set\n");
1734 #ifdef DEBUG
1735 		sii_DumpLog();
1736 #endif
1737 	}
1738 	regs->dmaddrl = ((u_long)dmaAddr >> 1);
1739 	regs->dmaddrh = ((u_long)dmaAddr >> 17) & 03;
1740 	regs->dmlotc = size;
1741 	regs->comm = SII_DMA | SII_INXFER | (regs->cstat & SII_STATE_MSK) |
1742 		phase;
1743 	wbflush();
1744 
1745 #ifdef DEBUG
1746 	if (sii_debug > 5) {
1747 		printf("sii_StartDMA: cs 0x%x, ds 0x%x, cm 0x%x, size %d\n",
1748 			regs->cstat, regs->dstat, regs->comm, size);
1749 	}
1750 #endif
1751 }
1752 
1753 /*
1754  * Call the device driver's 'done' routine to let it know the command is done.
1755  * The 'done' routine may try to start another command.
1756  * To be fair, we should start pending commands for other devices
1757  * before allowing the same device to start another command.
1758  */
1759 static void
1760 sii_CmdDone(sc, target, error)
1761 	struct siisoftc *sc;	/* which SII to use */
1762 	int target;			/* which device is done */
1763 	int error;			/* error code if any errors */
1764 {
1765 	ScsiCmd *scsicmd;
1766 	int i;
1767 
1768 	scsicmd = sc->sc_cmd[target];
1769 #ifdef DIAGNOSTIC
1770 	if (target < 0 || !scsicmd)
1771 		panic("sii_CmdDone");
1772 #endif
1773 	sc->sc_cmd[target] = (ScsiCmd *)0;
1774 #ifdef DEBUG
1775 	if (sii_debug > 1) {
1776 		printf("sii_CmdDone: %s target %d cmd %x err %d resid %d\n",
1777 			sc->sc_dev.dv_xname,
1778 			target, scsicmd->cmd[0], error, sc->sc_st[target].buflen);
1779 	}
1780 #endif
1781 
1782 	/* look for another device that is ready */
1783 	for (i = 0; i < SII_NCMD; i++) {
1784 		/* don't restart a disconnected command */
1785 		if (!sc->sc_cmd[i] || sc->sc_st[i].prevComm)
1786 			continue;
1787 		sii_StartCmd(sc, i);
1788 		break;
1789 	}
1790 
1791 	sc->sc_xs[target]->status = sc->sc_st[target].statusByte;
1792 	/*
1793 	 * Convert SII driver error code to MI SCSI XS_*.
1794 	 */
1795 	switch (error) {
1796 	case 0:
1797 		sc->sc_xs[target]->error = XS_NOERROR;
1798 		break;
1799 	case ENXIO:
1800 		sc->sc_xs[target]->error = XS_SELTIMEOUT;
1801 		break;
1802 	case EBUSY:
1803 		sc->sc_xs[target]->error = XS_BUSY;
1804 		break;
1805 	case EIO:
1806 		sc->sc_xs[target]->error = XS_DRIVER_STUFFUP;
1807 		break;
1808 	default:
1809 		sc->sc_xs[target]->error = XS_DRIVER_STUFFUP;
1810 	}
1811 	sc->sc_xs[target]->resid = sc->sc_st[target].buflen;
1812 	scsipi_done(sc->sc_xs[target]);
1813 }
1814 
1815 #ifdef DEBUG
1816 static void
1817 sii_DumpLog()
1818 {
1819 	struct sii_log *lp;
1820 
1821 	printf("sii: cmd %x bn %d cnt %d\n", sii_debug_cmd, sii_debug_bn,
1822 		sii_debug_sz);
1823 	lp = sii_logp;
1824 	do {
1825 		printf("target %d cs %x ds %x cm %x msg %x rlen %x dlen %x\n",
1826 			lp->target, lp->cstat, lp->dstat, lp->comm, lp->msg,
1827 			lp->rlen, lp->dlen);
1828 		if (++lp >= &sii_log[NLOG])
1829 			lp = sii_log;
1830 	} while (lp != sii_logp);
1831 }
1832 #endif
1833