xref: /netbsd-src/sys/arch/acorn32/podulebus/sfas.c (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 /*	$NetBSD: sfas.c,v 1.29 2020/07/22 01:24:39 msaitoh 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) 1995 Scott Stevens
39  * Copyright (c) 1995 Daniel Widenfalk
40  * Copyright (c) 1994 Christian E. Hopps
41  *
42  * This code is derived from software contributed to Berkeley by
43  * Van Jacobson of Lawrence Berkeley Laboratory.
44  *
45  * Redistribution and use in source and binary forms, with or without
46  * modification, are permitted provided that the following conditions
47  * are met:
48  * 1. Redistributions of source code must retain the above copyright
49  *    notice, this list of conditions and the following disclaimer.
50  * 2. Redistributions in binary form must reproduce the above copyright
51  *    notice, this list of conditions and the following disclaimer in the
52  *    documentation and/or other materials provided with the distribution.
53  * 3. All advertising materials mentioning features or use of this software
54  *    must display the following acknowledgement:
55  *	This product includes software developed by the University of
56  *	California, Berkeley and its contributors.
57  * 4. Neither the name of the University nor the names of its contributors
58  *    may be used to endorse or promote products derived from this software
59  *    without specific prior written permission.
60  *
61  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
62  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
63  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
64  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
65  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
66  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
67  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
68  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
69  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
70  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
71  * SUCH DAMAGE.
72  *
73  *	@(#)scsi.c	7.5 (Berkeley) 5/4/91
74  */
75 
76 /*
77  * Emulex FAS216 scsi adaptor driver
78  */
79 
80 /*
81  * Modified for NetBSD/arm32 by Scott Stevens
82  */
83 
84 #include <sys/cdefs.h>
85 __KERNEL_RCSID(0, "$NetBSD: sfas.c,v 1.29 2020/07/22 01:24:39 msaitoh Exp $");
86 
87 #include <sys/param.h>
88 #include <sys/systm.h>
89 #include <sys/device.h>
90 #include <sys/buf.h>
91 #include <sys/proc.h>
92 
93 #include <dev/scsipi/scsi_all.h>
94 #include <dev/scsipi/scsipi_all.h>
95 #include <dev/scsipi/scsiconf.h>
96 
97 #include <uvm/uvm_extern.h>
98 
99 #include <machine/pmap.h>
100 #include <machine/cpu.h>
101 #include <machine/io.h>
102 #include <machine/intr.h>
103 #include <acorn32/podulebus/podulebus.h>
104 #include <acorn32/podulebus/sfasreg.h>
105 #include <acorn32/podulebus/sfasvar.h>
106 
107 void sfas_minphys(struct buf *);
108 void sfas_init_nexus(struct sfas_softc *, struct nexus *);
109 void sfasinitialize(struct sfas_softc *);
110 void sfas_scsi_request(struct scsipi_channel *, scsipi_adapter_req_t, void *);
111 void sfas_donextcmd(struct sfas_softc *, struct sfas_pending *);
112 void sfas_scsidone(struct sfas_softc *, struct scsipi_xfer *, int);
113 void sfasintr(struct sfas_softc *);
114 void sfasiwait(struct sfas_softc *);
115 void sfas_ixfer(void *, int);
116 void sfasreset(struct sfas_softc *, int);
117 int  sfasselect(struct sfas_softc *, struct sfas_pending *, unsigned char *,
118 		int, unsigned char *, int, int);
119 void sfasicmd(struct sfas_softc *, struct sfas_pending *);
120 void sfasgo(struct sfas_softc *, struct sfas_pending *);
121 void sfas_save_pointers(struct sfas_softc *);
122 void sfas_restore_pointers(struct sfas_softc *);
123 void sfas_build_sdtrm(struct sfas_softc *, int, int);
124 int sfas_select_unit(struct sfas_softc *, short);
125 struct nexus *sfas_arbitate_target(struct sfas_softc *, int);
126 void sfas_setup_nexus(struct sfas_softc *, struct nexus *,
127 		      struct sfas_pending *, unsigned char *, int,
128 		      unsigned char *, int, int);
129 int sfas_pretests(struct sfas_softc *, sfas_regmap_p);
130 int sfas_midaction(struct sfas_softc *, sfas_regmap_p, struct nexus *);
131 int sfas_postaction(struct sfas_softc *, sfas_regmap_p, struct nexus *);
132 
133 /*
134  * Initialize these to make 'em patchable. Defaults to enable sync and discon.
135  */
136 u_char	sfas_inhibit_sync[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
137 u_char	sfas_inhibit_disc[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
138 
139 #undef DEBUG
140 #define DEBUG
141 #ifdef DEBUG
142 #define QPRINTF(a) if (sfas_debug > 1) printf a
143 int	sfas_debug = 2;
144 #else
145 #define QPRINTF
146 #endif
147 
148 /*
149  * default minphys routine for sfas based controllers
150  */
151 void
152 sfas_minphys(struct buf *bp)
153 {
154 
155 	/*
156 	 * No max transfer at this level.
157 	 */
158 	minphys(bp);
159 }
160 
161 /*
162  * Initialize the nexus structs.
163  */
164 void
165 sfas_init_nexus(struct sfas_softc *dev, struct nexus *nexus)
166 {
167 	memset(nexus, 0, sizeof(struct nexus));
168 
169 	nexus->state	= SFAS_NS_IDLE;
170 	nexus->period	= 200;
171 	nexus->offset	= 0;
172 	nexus->syncper	= 5;
173 	nexus->syncoff	= 0;
174 	nexus->config3	= dev->sc_config3 & ~SFAS_CFG3_FASTSCSI;
175 }
176 
177 void
178 sfasinitialize(struct sfas_softc *dev)
179 {
180 	int		 i;
181 
182 	dev->sc_led_status = 0;
183 
184 	TAILQ_INIT(&dev->sc_xs_pending);
185 	TAILQ_INIT(&dev->sc_xs_free);
186 
187 /*
188  * Initialize the sfas_pending structs and link them into the free list. We
189  * have to set vm_link_data.pages to 0 or the vm FIX won't work.
190  */
191 	for(i=0; i<MAXPENDING; i++) {
192 		TAILQ_INSERT_TAIL(&dev->sc_xs_free, &dev->sc_xs_store[i],
193 				  link);
194 	}
195 
196 /*
197  * Calculate the correct clock conversion factor 2 <= factor <= 8, i.e. set
198  * the factor to clock_freq / 5 (int).
199  */
200 	if (dev->sc_clock_freq <= 10)
201 		dev->sc_clock_conv_fact = 2;
202 	if (dev->sc_clock_freq <= 40)
203 		dev->sc_clock_conv_fact = 2+((dev->sc_clock_freq-10)/5);
204 	else
205 		panic("sfasinitialize: Clock frequence too high");
206 
207 /* Setup and save the basic configuration registers */
208 	dev->sc_config1 = (dev->sc_host_id & SFAS_CFG1_BUS_ID_MASK);
209 	dev->sc_config2 = SFAS_CFG2_FEATURES_ENABLE;
210 	dev->sc_config3 = (dev->sc_clock_freq > 25 ? SFAS_CFG3_FASTCLK : 0);
211 
212 /* Precalculate timeout value and clock period. */
213 /* Ekkk ... floating point in the kernel !!!! */
214 /*	dev->sc_timeout_val  = 1+dev->sc_timeout*dev->sc_clock_freq/
215 				 (7.682*dev->sc_clock_conv_fact);*/
216 	dev->sc_timeout_val  = 1+dev->sc_timeout*dev->sc_clock_freq/
217 				 ((7682*dev->sc_clock_conv_fact)/1000);
218 	dev->sc_clock_period = 1000/dev->sc_clock_freq;
219 
220 	sfasreset(dev, 1 | 2);	/* Reset Chip and Bus */
221 
222 	dev->sc_units_disconnected = 0;
223 	dev->sc_msg_in_len = 0;
224 	dev->sc_msg_out_len = 0;
225 
226 	dev->sc_flags = 0;
227 
228 	for(i=0; i<8; i++)
229 		sfas_init_nexus(dev, &dev->sc_nexus[i]);
230 
231 	if (dev->sc_ixfer == NULL)
232 		dev->sc_ixfer = sfas_ixfer;
233 
234 /*
235  * Setup bump buffer.
236  */
237 	dev->sc_bump_va = (u_char *)uvm_km_alloc(kernel_map, dev->sc_bump_sz, 0,
238 	    UVM_KMF_WIRED | UVM_KMF_ZERO);
239 	(void) pmap_extract(pmap_kernel(), (vaddr_t)dev->sc_bump_va,
240 	    (paddr_t *)&dev->sc_bump_pa);
241 
242 /*
243  * Setup pages to noncachable, that way we don't have to flush the cache
244  * every time we need "bumped" transfer.
245  */
246 	pt_entry_t * const ptep = vtopte((vaddr_t) dev->sc_bump_va);
247 	const pt_entry_t opte = *ptep;
248 	const pt_entry_t npte = opte & ~(L2_C | L2_B);
249 	l2pte_set(ptep, npte, opte);
250 	PTE_SYNC(ptep);
251 	cpu_tlb_flushD();
252 	cpu_dcache_wbinv_range((vaddr_t)dev->sc_bump_va, PAGE_SIZE);
253 
254 	printf(" dmabuf V0x%08x P0x%08x", (u_int)dev->sc_bump_va, (u_int)dev->sc_bump_pa);
255 }
256 
257 
258 /*
259  * used by specific sfas controller
260  */
261 void
262 sfas_scsi_request(struct scsipi_channel *chan, scsipi_adapter_req_t req,
263 								void *arg)
264 {
265 	struct scsipi_xfer *xs;
266 	struct sfas_softc	*dev = device_private(chan->chan_adapter->adapt_dev);
267 	struct scsipi_periph	*periph;
268 	struct sfas_pending	*pendp;
269 	int			 flags, s, target;
270 
271 	switch (req) {
272 	case ADAPTER_REQ_RUN_XFER:
273 		xs = arg;
274 		periph = xs->xs_periph;
275 		flags = xs->xs_control;
276 		target = periph->periph_target;
277 
278 		if (flags & XS_CTL_DATA_UIO)
279 			panic("sfas: scsi data uio requested");
280 
281 		if ((flags & XS_CTL_POLL) && (dev->sc_flags & SFAS_ACTIVE))
282 			panic("sfas_scsicmd: busy");
283 
284 /* Get hold of a sfas_pending block. */
285 		s = splbio();
286 		pendp = dev->sc_xs_free.tqh_first;
287 		if (pendp == NULL) {
288 			xs->error = XS_RESOURCE_SHORTAGE;
289 			scsipi_done(xs);
290 			splx(s);
291 			return;
292 		}
293 		TAILQ_REMOVE(&dev->sc_xs_free, pendp, link);
294 		pendp->xs = xs;
295 		splx(s);
296 
297 
298 /* If the chip if busy OR the unit is busy, we have to wait for out turn. */
299 		if ((dev->sc_flags & SFAS_ACTIVE) ||
300 		    (dev->sc_nexus[target].flags & SFAS_NF_UNIT_BUSY)) {
301 			s = splbio();
302 			TAILQ_INSERT_TAIL(&dev->sc_xs_pending, pendp, link);
303 			splx(s);
304 		} else
305 			sfas_donextcmd(dev, pendp);
306 
307 		return;
308 
309 	case ADAPTER_REQ_GROW_RESOURCES:
310 	case ADAPTER_REQ_SET_XFER_MODE:
311 		/* XXX Not supported. */
312 		return;
313 	}
314 }
315 
316 /*
317  * Actually select the unit, whereby the whole scsi-process is started.
318  */
319 void
320 sfas_donextcmd(struct sfas_softc *dev, struct sfas_pending *pendp)
321 {
322 	int	s;
323 
324 /*
325  * Special case for scsi unit reset. I think this is waterproof. We first
326  * select the unit during splbio. We then cycle through the generated
327  * interrupts until the interrupt routine signals that the unit has
328  * acknowledged the reset. After that we have to wait a reset to select
329  * delay before anything else can happend.
330  */
331 	if (pendp->xs->xs_control & XS_CTL_RESET) {
332 		struct nexus	*nexus;
333 
334 		s = splbio();
335 		while(!sfasselect(dev, pendp, 0, 0, 0, 0, SFAS_SELECT_K)) {
336 			splx(s);
337 			delay(10);
338 			s = splbio();
339 		}
340 
341 		nexus = dev->sc_cur_nexus;
342 		while(nexus->flags & SFAS_NF_UNIT_BUSY) {
343 			sfasiwait(dev);
344 			sfasintr(dev);
345 		}
346 
347 		nexus->flags |= SFAS_NF_UNIT_BUSY;
348 		splx(s);
349 
350 		sfasreset(dev, 0);
351 
352 		s = splbio();
353 		nexus->flags &= ~SFAS_NF_UNIT_BUSY;
354 		splx(s);
355 	}
356 
357 /*
358  * If we are polling, go to splbio and perform the command, else we poke
359  * the scsi-bus via sfasgo to get the interrupt machine going.
360  */
361 	if (pendp->xs->xs_control & XS_CTL_POLL) {
362 		s = splbio();
363 		sfasicmd(dev, pendp);
364 		TAILQ_INSERT_TAIL(&dev->sc_xs_free, pendp, link);
365 		splx(s);
366 	} else {
367 		sfasgo(dev, pendp);
368 	}
369 }
370 
371 void
372 sfas_scsidone(struct sfas_softc *dev, struct scsipi_xfer *xs, int stat)
373 {
374 	struct sfas_pending	*pendp;
375 	int			 s;
376 
377 	xs->status = stat;
378 
379 	if (stat == 0)
380 		xs->resid = 0;
381 	else {
382 		switch(stat) {
383 		case SCSI_CHECK:
384 		case SCSI_BUSY:
385 			xs->error = XS_BUSY;
386 			break;
387 		case -1:
388 			xs->error = XS_DRIVER_STUFFUP;
389 			QPRINTF(("sfas_scsicmd() bad %x\n", stat));
390 			break;
391 		default:
392 			xs->error = XS_TIMEOUT;
393 			break;
394 		}
395 	}
396 
397 /* Steal the next command from the queue so that one unit can't hog the bus. */
398 	s = splbio();
399 	pendp = dev->sc_xs_pending.tqh_first;
400 	while(pendp) {
401 		if (!(dev->sc_nexus[pendp->xs->xs_periph->periph_target].flags &
402 		      SFAS_NF_UNIT_BUSY))
403 			break;
404 		pendp = pendp->link.tqe_next;
405 	}
406 
407 	if (pendp != NULL) {
408 		TAILQ_REMOVE(&dev->sc_xs_pending, pendp, link);
409 	}
410 
411 	splx(s);
412 	scsipi_done(xs);
413 
414 	if (pendp)
415 		sfas_donextcmd(dev, pendp);
416 }
417 
418 /*
419  * There are two kinds of reset:
420  *  1) CHIP-bus reset. This also implies a SCSI-bus reset.
421  *  2) SCSI-bus reset.
422  * After the appropriate resets have been performed we wait a reset to select
423  * delay time.
424  */
425 void
426 sfasreset(struct sfas_softc *dev, int how)
427 {
428 	sfas_regmap_p	rp;
429 	int		i, s;
430 
431 	rp = dev->sc_fas;
432 
433 	if (how & 1) {
434 		for(i=0; i<8; i++)
435 			sfas_init_nexus(dev, &dev->sc_nexus[i]);
436 
437 		*rp->sfas_command = SFAS_CMD_RESET_CHIP;
438 		delay(1);
439 		*rp->sfas_command = SFAS_CMD_NOP;
440 
441 		*rp->sfas_config1 = dev->sc_config1;
442 		*rp->sfas_config2 = dev->sc_config2;
443 		*rp->sfas_config3 = dev->sc_config3;
444 		*rp->sfas_timeout = dev->sc_timeout_val;
445 		*rp->sfas_clkconv = dev->sc_clock_conv_fact &
446 					SFAS_CLOCK_CONVERSION_MASK;
447 	}
448 
449 	if (how & 2) {
450 		for(i=0; i<8; i++)
451 			sfas_init_nexus(dev, &dev->sc_nexus[i]);
452 
453 		s = splbio();
454 
455 		*rp->sfas_command = SFAS_CMD_RESET_SCSI_BUS;
456 		delay(100);
457 
458 /* Skip interrupt generated by RESET_SCSI_BUS */
459 		while(*rp->sfas_status & SFAS_STAT_INTERRUPT_PENDING) {
460 			dev->sc_status = *rp->sfas_status;
461 			dev->sc_interrupt = *rp->sfas_interrupt;
462 
463 			delay(100);
464 		}
465 
466 		dev->sc_status = *rp->sfas_status;
467 		dev->sc_interrupt = *rp->sfas_interrupt;
468 
469 		splx(s);
470 	}
471 
472 	if (dev->sc_config_flags & SFAS_SLOW_START)
473 		delay(4*250000); /* RESET to SELECT DELAY*4 for slow devices */
474 	else
475 		delay(250000);	 /* RESET to SELECT DELAY */
476 }
477 
478 /*
479  * Save active data pointers to the nexus block currently active.
480  */
481 void
482 sfas_save_pointers(struct sfas_softc *dev)
483 {
484 	struct nexus	*nx;
485 
486 	nx = dev->sc_cur_nexus;
487 	if (nx) {
488 		nx->cur_link	= dev->sc_cur_link;
489 		nx->max_link	= dev->sc_max_link;
490 		nx->buf		= dev->sc_buf;
491 		nx->len		= dev->sc_len;
492 		nx->dma_len	= dev->sc_dma_len;
493 		nx->dma_buf	= dev->sc_dma_buf;
494 		nx->dma_blk_flg	= dev->sc_dma_blk_flg;
495 		nx->dma_blk_len	= dev->sc_dma_blk_len;
496 		nx->dma_blk_ptr	= dev->sc_dma_blk_ptr;
497 	}
498 }
499 
500 /*
501  * Restore data pointers from the currently active nexus block.
502  */
503 void
504 sfas_restore_pointers(struct sfas_softc *dev)
505 {
506 	struct nexus	*nx;
507 
508 	nx = dev->sc_cur_nexus;
509 	if (nx) {
510 		dev->sc_cur_link    = nx->cur_link;
511 		dev->sc_max_link    = nx->max_link;
512 		dev->sc_buf	    = nx->buf;
513 		dev->sc_len	    = nx->len;
514 		dev->sc_dma_len	    = nx->dma_len;
515 		dev->sc_dma_buf	    = nx->dma_buf;
516 		dev->sc_dma_blk_flg = nx->dma_blk_flg;
517 		dev->sc_dma_blk_len = nx->dma_blk_len;
518 		dev->sc_dma_blk_ptr = nx->dma_blk_ptr;
519 		dev->sc_chain	    = nx->dma;
520 		dev->sc_unit	    = (nx->lun_unit & 0x0F);
521 		dev->sc_lun	    = (nx->lun_unit & 0xF0) >> 4;
522 	}
523 }
524 
525 /*
526  * sfasiwait is used during interrupt and polled IO to wait for an event from
527  * the FAS chip. This function MUST NOT BE CALLED without interrupt disabled.
528  */
529 void
530 sfasiwait(struct sfas_softc *dev)
531 {
532 	sfas_regmap_p	rp;
533 
534 /*
535  * If SFAS_DONT_WAIT is set, we have already grabbed the interrupt info
536  * elsewhere. So we don't have to wait for it.
537  */
538 	if (dev->sc_flags & SFAS_DONT_WAIT) {
539 		dev->sc_flags &= ~SFAS_DONT_WAIT;
540 		return;
541 	}
542 
543 	rp = dev->sc_fas;
544 
545 /* Wait for FAS chip to signal an interrupt. */
546 	while(!(*rp->sfas_status & SFAS_STAT_INTERRUPT_PENDING))
547 		delay(1);
548 
549 /* Grab interrupt info from chip. */
550 	dev->sc_status = *rp->sfas_status;
551 	dev->sc_interrupt = *rp->sfas_interrupt;
552 	if (dev->sc_interrupt & SFAS_INT_RESELECTED) {
553 		dev->sc_resel[0] = *rp->sfas_fifo;
554 		dev->sc_resel[1] = *rp->sfas_fifo;
555 	}
556 }
557 
558 /*
559  * Transfer info to/from device. sfas_ixfer uses polled IO+sfasiwait so the
560  * rules that apply to sfasiwait also applies here.
561  */
562 void
563 sfas_ixfer(void *v, int polling)
564 {
565 	struct sfas_softc *dev = v;
566 	sfas_regmap_p	 rp;
567 	u_char		*buf;
568 	int		 len, mode, phase;
569 
570 	rp = dev->sc_fas;
571 	buf = dev->sc_buf;
572 	len = dev->sc_len;
573 
574 /*
575  * Decode the scsi phase to determine whether we are reading or writing.
576  * mode == 1 => READ, mode == 0 => WRITE
577  */
578 	phase = dev->sc_status & SFAS_STAT_PHASE_MASK;
579 	mode = (phase == SFAS_PHASE_DATA_IN);
580 
581 	while(len && ((dev->sc_status & SFAS_STAT_PHASE_MASK) == phase))
582 		if (mode) {
583 			*rp->sfas_command = SFAS_CMD_TRANSFER_INFO;
584 
585 			sfasiwait(dev);
586 
587 			*buf++ = *rp->sfas_fifo;
588 			len--;
589 		} else {
590 			len--;
591 			*rp->sfas_fifo = *buf++;
592 			*rp->sfas_command = SFAS_CMD_TRANSFER_INFO;
593 
594 			sfasiwait(dev);
595 		}
596 
597 /* Update buffer pointers to reflect the sent/received data. */
598 	dev->sc_buf = buf;
599 	dev->sc_len = len;
600 
601 /*
602  * Since the last sfasiwait will be a phase-change, we can't wait for it
603  * again later, so we have to signal that.
604  * Since this may be called from an interrupt initiated routine then we
605  * must call sfasintr again to avoid losing an interrupt. Phew!
606  */
607 	if(polling)
608 		dev->sc_flags |= SFAS_DONT_WAIT;
609 	else
610 		sfasintr(dev);
611 }
612 
613 /*
614  * Build a Synchronous Data Transfer Request message
615  */
616 void
617 sfas_build_sdtrm(struct sfas_softc *dev, int period, int offset)
618 {
619 	dev->sc_msg_out[0] = 0x01;
620 	dev->sc_msg_out[1] = 0x03;
621 	dev->sc_msg_out[2] = 0x01;
622 	dev->sc_msg_out[3] = period/4;
623 	dev->sc_msg_out[4] = offset;
624 	dev->sc_msg_out_len= 5;
625 }
626 
627 /*
628  * Arbitate the scsi bus and select the unit
629  */
630 int
631 sfas_select_unit(struct sfas_softc *dev, short target)
632 {
633 	sfas_regmap_p	 rp;
634 	struct nexus	*nexus;
635 	int		 s, retcode, i;
636 	u_char		 cmd;
637 
638 	s = splbio();	/* Do this at splbio so that we won't be disturbed. */
639 
640 	retcode = 0;
641 
642 	nexus = &dev->sc_nexus[target];
643 
644 /*
645  * Check if the chip is busy. If not the we mark it as so and hope that nobody
646  * reselects us until we have grabbed the bus.
647  */
648 	if (!(dev->sc_flags & SFAS_ACTIVE) && !dev->sc_sel_nexus) {
649 		dev->sc_flags |= SFAS_ACTIVE;
650 
651 		rp = dev->sc_fas;
652 
653 		*rp->sfas_syncper = nexus->syncper;
654 		*rp->sfas_syncoff = nexus->syncoff;
655 		*rp->sfas_config3 = nexus->config3;
656 
657 		*rp->sfas_config1 = dev->sc_config1;
658 		*rp->sfas_timeout = dev->sc_timeout_val;
659 		*rp->sfas_dest_id = target;
660 
661 /* If nobody has stolen the bus, we can send a select command to the chip. */
662 		if (!(*rp->sfas_status & SFAS_STAT_INTERRUPT_PENDING)) {
663 			*rp->sfas_fifo = nexus->ID;
664 			if ((nexus->flags & (SFAS_NF_DO_SDTR | SFAS_NF_RESET))
665 			    || (dev->sc_msg_out_len != 0))
666 				cmd = SFAS_CMD_SEL_ATN_STOP;
667 			else {
668 				for(i=0; i<nexus->clen; i++)
669 					*rp->sfas_fifo = nexus->cbuf[i];
670 
671 				cmd = SFAS_CMD_SEL_ATN;
672 			}
673 
674 			dev->sc_sel_nexus = nexus;
675 
676 			*rp->sfas_command = cmd;
677 			retcode = 1;
678 			nexus->flags &= ~SFAS_NF_RETRY_SELECT;
679 		} else
680 			nexus->flags |= SFAS_NF_RETRY_SELECT;
681 	} else
682 		nexus->flags |= SFAS_NF_RETRY_SELECT;
683 
684 	splx(s);
685 	return(retcode);
686 }
687 
688 /*
689  * Grab the nexus if available else return 0.
690  */
691 struct nexus *
692 sfas_arbitate_target(struct sfas_softc *dev, int target)
693 {
694 	struct nexus	*nexus;
695 	int		 s;
696 
697 /*
698  * This is realy simple. Raise interrupt level to splbio. Grab the nexus and
699  * leave.
700  */
701 	nexus = &dev->sc_nexus[target];
702 
703 	s = splbio();
704 
705 	if (nexus->flags & SFAS_NF_UNIT_BUSY)
706 		nexus = 0;
707 	else
708 		nexus->flags |= SFAS_NF_UNIT_BUSY;
709 
710 	splx(s);
711 	return(nexus);
712 }
713 
714 /*
715  * Setup a nexus for use. Initializes command, buffer pointers and DMA chain.
716  */
717 void
718 sfas_setup_nexus(struct sfas_softc *dev, struct nexus *nexus, struct sfas_pending *pendp, unsigned char *cbuf, int clen, unsigned char *buf, int len, int mode)
719 {
720 	char	sync, target, lun;
721 
722 	target = pendp->xs->xs_periph->periph_target;
723 	lun    = pendp->xs->xs_periph->periph_lun;
724 
725 /*
726  * Adopt mode to reflect the config flags.
727  * If we can't use DMA we can't use synch transfer. Also check the
728  * sfas_inhibit_xxx[target] flags.
729  */
730 	if ((dev->sc_config_flags & (SFAS_NO_SYNCH | SFAS_NO_DMA)) ||
731 	    sfas_inhibit_sync[(int)target])
732 		mode &= ~SFAS_SELECT_S;
733 
734 	if ((dev->sc_config_flags & SFAS_NO_RESELECT) ||
735 	    sfas_inhibit_disc[(int)target])
736 		mode &= ~SFAS_SELECT_R;
737 
738 	nexus->xs		= pendp->xs;
739 
740 /* Setup the nexus struct. */
741 	nexus->ID	   = ((mode & SFAS_SELECT_R) ? 0xC0 : 0x80) | lun;
742 	nexus->clen	   = clen;
743 	memcpy(nexus->cbuf, cbuf, nexus->clen);
744 	nexus->cbuf[1] |= lun << 5;		/* Fix the lun bits */
745 	nexus->cur_link	   = 0;
746 	nexus->dma_len	   = 0;
747 	nexus->dma_buf	   = 0;
748 	nexus->dma_blk_len = 0;
749 	nexus->dma_blk_ptr = 0;
750 	nexus->len	   = len;
751 	nexus->buf	   = buf;
752 	nexus->lun_unit	   = (lun << 4) | target;
753 	nexus->state	   = SFAS_NS_SELECTED;
754 
755 /* We must keep these flags. All else must be zero. */
756 	nexus->flags	  &= SFAS_NF_UNIT_BUSY
757 			   | SFAS_NF_SYNC_TESTED | SFAS_NF_SELECT_ME;
758 
759 	if (mode & SFAS_SELECT_I)
760 		nexus->flags |= SFAS_NF_IMMEDIATE;
761 	if (mode & SFAS_SELECT_K)
762 		nexus->flags |= SFAS_NF_RESET;
763 
764 	sync  = ((mode & SFAS_SELECT_S) ? 1 : 0);
765 
766 /* We can't use sync during polled IO. */
767 	if (sync && (mode & SFAS_SELECT_I))
768 		sync = 0;
769 
770 	if (!sync &&
771 	    ((nexus->flags & SFAS_NF_SYNC_TESTED) && (nexus->offset != 0))) {
772 		/*
773 		 * If the scsi unit is set to synch transfer and we don't want
774 		 * that, we have to renegotiate.
775 		 */
776 
777 		nexus->flags |= SFAS_NF_DO_SDTR;
778 		nexus->period = 200;
779 		nexus->offset = 0;
780 	} else if (sync && !(nexus->flags & SFAS_NF_SYNC_TESTED)) {
781 		/*
782 		 * If the scsi unit is not set to synch transfer and we want
783 		 * that, we have to negotiate. This should realy base the
784 		 * period on the clock frequence rather than just check if
785 		 * >25 MHz
786 		 */
787 
788 		nexus->flags |= SFAS_NF_DO_SDTR;
789 		nexus->period = ((dev->sc_clock_freq>25) ? 100 : 200);
790 		nexus->offset = 8;
791 
792 		/* If the user has a long cable, we want to limit the period */
793 		if ((nexus->period == 100) &&
794 		    (dev->sc_config_flags & SFAS_SLOW_CABLE))
795 			nexus->period = 200;
796 	}
797 
798 /*
799  * Fake a DMA-block for polled IO. This way we can use the same code to handle
800  * reselection. Much nicer this way.
801  */
802 	if ((mode & SFAS_SELECT_I) || (dev->sc_config_flags & SFAS_NO_DMA)) {
803 		nexus->dma[0].ptr = buf;
804 		nexus->dma[0].len = len;
805 		nexus->dma[0].flg = SFAS_CHAIN_PRG;
806 		nexus->max_link   = 1;
807 	} else {
808 		nexus->max_link = dev->sc_build_dma_chain(dev, nexus->dma,
809 							  buf, len);
810 	}
811 
812 /* Flush the caches. */
813 
814 	if (len && !(mode & SFAS_SELECT_I))
815 		cpu_dcache_wbinv_range((vaddr_t)buf, len);
816 }
817 
818 int
819 sfasselect(struct sfas_softc *dev, struct sfas_pending *pendp, unsigned char *cbuf, int clen, unsigned char *buf, int len, int mode)
820 {
821 	struct nexus	*nexus;
822 
823 /* Get the nexus struct. */
824 	nexus = sfas_arbitate_target(dev, pendp->xs->xs_periph->periph_target);
825 	if (nexus == NULL)
826 		return(0);
827 
828 /* Setup the nexus struct. */
829 	sfas_setup_nexus(dev, nexus, pendp, cbuf, clen, buf, len, mode);
830 
831 /* Post it to the interrupt machine. */
832 	sfas_select_unit(dev, pendp->xs->xs_periph->periph_target);
833 
834 	return(1);
835 }
836 
837 void
838 sfasgo(struct sfas_softc *dev, struct sfas_pending *pendp)
839 {
840 	int	 s;
841 	char	*buf;
842 
843 	buf    = pendp->xs->data;
844 
845 	if (sfasselect(dev, pendp, (char *)pendp->xs->cmd, pendp->xs->cmdlen,
846 		      buf, pendp->xs->datalen, SFAS_SELECT_RS)) {
847 		/*
848 		 * We got the command going so the sfas_pending struct is now
849 		 * free to reuse.
850 		 */
851 
852 		s = splbio();
853 		TAILQ_INSERT_TAIL(&dev->sc_xs_free, pendp, link);
854 		splx(s);
855 	} else {
856 		/*
857 		 * We couldn't make the command fly so we have to wait. The
858 		 * struct MUST be inserted at the head to keep the order of
859 		 * the commands.
860 		 */
861 
862 		s = splbio();
863 		TAILQ_INSERT_HEAD(&dev->sc_xs_pending, pendp, link);
864 		splx(s);
865 	}
866 
867 	return;
868 }
869 
870 /*
871  * Part one of the interrupt machine. Error checks and reselection test.
872  * We don't know if we have an active nexus here!
873  */
874 int
875 sfas_pretests(struct sfas_softc *dev, sfas_regmap_p rp)
876 {
877 	struct nexus	*nexus;
878 	int		 i, s;
879 
880 	if (dev->sc_interrupt & SFAS_INT_SCSI_RESET_DETECTED) {
881 		/*
882 		 * Cleanup and notify user. Lets hope that this is all we
883 		 * have to do
884 		 */
885 
886 		for(i=0; i<8; i++) {
887 			if (dev->sc_nexus[i].xs)
888 				sfas_scsidone(dev, dev->sc_nexus[i].xs, -2);
889 
890 			sfas_init_nexus(dev, &dev->sc_nexus[i]);
891 		}
892 		printf("sfasintr: SCSI-RESET detected!");
893 		return(-1);
894 	}
895 
896 	if (dev->sc_interrupt & SFAS_INT_ILLEGAL_COMMAND) {
897 		/* Something went terrible wrong! Dump some data and panic! */
898 
899 		printf("FIFO:");
900 		while(*rp->sfas_fifo_flags & SFAS_FIFO_COUNT_MASK)
901 			printf(" %x", *rp->sfas_fifo);
902 		printf("\n");
903 
904 		printf("CMD: %x\n", *rp->sfas_command);
905 		panic("sfasintr: ILLEGAL COMMAND!");
906 	}
907 
908 	if (dev->sc_interrupt & SFAS_INT_RESELECTED) {
909 		/* We were reselected. Set the chip as busy */
910 
911 		s = splbio();
912 		dev->sc_flags |= SFAS_ACTIVE;
913 		if (dev->sc_sel_nexus) {
914 			dev->sc_sel_nexus->flags |= SFAS_NF_SELECT_ME;
915 			dev->sc_sel_nexus = 0;
916 		}
917 		splx(s);
918 
919 		if (dev->sc_units_disconnected) {
920 			/* Find out who reselected us. */
921 
922 			dev->sc_resel[0] &= ~(1<<dev->sc_host_id);
923 
924 			for(i=0; i<8; i++)
925 				if (dev->sc_resel[0] & (1<<i))
926 					break;
927 
928 			if (i == 8)
929 				panic("Illegal reselection!");
930 
931 			if (dev->sc_nexus[i].state == SFAS_NS_DISCONNECTED) {
932 				/*
933 				 * This unit had disconnected, so we reconnect
934 				 * it.
935 				 */
936 
937 				dev->sc_cur_nexus = &dev->sc_nexus[i];
938 				nexus = dev->sc_cur_nexus;
939 
940 				*rp->sfas_syncper = nexus->syncper;
941 				*rp->sfas_syncoff = nexus->syncoff;
942 				*rp->sfas_config3 = nexus->config3;
943 
944 				*rp->sfas_dest_id = i & 7;
945 
946 				dev->sc_units_disconnected--;
947 				dev->sc_msg_in_len= 0;
948 
949 				/* Restore active pointers. */
950 				sfas_restore_pointers(dev);
951 
952 				nexus->state = SFAS_NS_RESELECTED;
953 
954 				*rp->sfas_command = SFAS_CMD_MESSAGE_ACCEPTED;
955 
956 				return(1);
957 			}
958 		}
959 
960 		/* Somehow we got an illegal reselection. Dump and panic. */
961 		printf("sfasintr: resel[0] %x resel[1] %x disconnected %d\n",
962 		       dev->sc_resel[0], dev->sc_resel[1],
963 		       dev->sc_units_disconnected);
964 		panic("sfasintr: Unexpected reselection!");
965 	}
966 
967 	return(0);
968 }
969 
970 /*
971  * Part two of the interrupt machine. Handle disconnection and post command
972  * processing. We know that we have an active nexus here.
973  */
974 int
975 sfas_midaction(struct sfas_softc *dev, sfas_regmap_p rp, struct nexus *nexus)
976 {
977 	int	i, left, len, s;
978 	u_char	status, msg;
979 
980 	if (dev->sc_interrupt & SFAS_INT_DISCONNECT) {
981 		s = splbio();
982 		dev->sc_cur_nexus = 0;
983 
984 		/* Mark chip as busy and clean up the chip FIFO. */
985 		dev->sc_flags &= ~SFAS_ACTIVE;
986 		*rp->sfas_command = SFAS_CMD_FLUSH_FIFO;
987 
988 		/* Let the nexus state reflect what we have to do. */
989 		switch(nexus->state) {
990 		case SFAS_NS_SELECTED:
991 			dev->sc_sel_nexus = 0;
992 			nexus->flags &= ~SFAS_NF_SELECT_ME;
993 
994 			/*
995 			 * We were trying to select the unit. Probably no unit
996 			 * at this ID.
997 			 */
998 			nexus->xs->resid = dev->sc_len;
999 
1000 			nexus->status = -2;
1001 			nexus->flags &= ~SFAS_NF_UNIT_BUSY;
1002 			nexus->state = SFAS_NS_FINISHED;
1003 			break;
1004 
1005 		case SFAS_NS_DONE:
1006 			/* All done. */
1007 			nexus->xs->resid = dev->sc_len;
1008 
1009 			nexus->flags &= ~SFAS_NF_UNIT_BUSY;
1010 			nexus->state  = SFAS_NS_FINISHED;
1011 			dev->sc_led(dev, 0);
1012 			break;
1013 
1014 		case SFAS_NS_DISCONNECTING:
1015 			/*
1016 			 * We have received a DISCONNECT message, so we are
1017 			 * doing a normal disconnection.
1018 			 */
1019 			nexus->state = SFAS_NS_DISCONNECTED;
1020 
1021 			dev->sc_units_disconnected++;
1022 			break;
1023 
1024 		case SFAS_NS_RESET:
1025 			/*
1026 			 * We were resetting this SCSI-unit. Clean up the
1027 			 * nexus struct.
1028 			 */
1029 			dev->sc_led(dev, 0);
1030 			sfas_init_nexus(dev, nexus);
1031 			break;
1032 
1033 		default:
1034 			/*
1035 			 * Unexpected disconnection! Cleanup and exit. This
1036 			 * shouldn't cause any problems.
1037 			 */
1038 			printf("sfasintr: Unexpected disconnection\n");
1039 			printf("sfasintr: u %x s %d p %d f %x c %x\n",
1040 			       nexus->lun_unit, nexus->state,
1041 			       dev->sc_status & SFAS_STAT_PHASE_MASK,
1042 			       nexus->flags, nexus->cbuf[0]);
1043 
1044 			nexus->xs->resid = dev->sc_len;
1045 
1046 			nexus->flags &= ~SFAS_NF_UNIT_BUSY;
1047 			nexus->state = SFAS_NS_FINISHED;
1048 			nexus->status = -3;
1049 
1050 			dev->sc_led(dev, 0);
1051 			break;
1052 		}
1053 
1054 		/*
1055 		 * If we have disconnected units, we MUST enable reselection
1056 		 * within 250ms.
1057 		 */
1058 		if (dev->sc_units_disconnected &&
1059 		    !(dev->sc_flags & SFAS_ACTIVE))
1060 			*rp->sfas_command = SFAS_CMD_ENABLE_RESEL;
1061 
1062 		splx(s);
1063 
1064 		/* Select the first pre-initialized nexus we find. */
1065 		for(i=0; i<8; i++)
1066 			if (dev->sc_nexus[i].flags & (SFAS_NF_SELECT_ME | SFAS_NF_RETRY_SELECT))
1067 				if (sfas_select_unit(dev, i) == 2)
1068 					break;
1069 
1070 		/* We are done with this nexus! */
1071 		if (nexus->state == SFAS_NS_FINISHED)
1072 			sfas_scsidone(dev, nexus->xs, nexus->status);
1073 
1074 		return(1);
1075 	}
1076 
1077 	switch(nexus->state) {
1078 	case SFAS_NS_SELECTED:
1079 		dev->sc_cur_nexus = nexus;
1080 		dev->sc_sel_nexus = 0;
1081 
1082 		nexus->flags &= ~SFAS_NF_SELECT_ME;
1083 
1084 		/*
1085 		 * We have selected a unit. Setup chip, restore pointers and
1086 		 * light the led.
1087 		 */
1088 		*rp->sfas_syncper = nexus->syncper;
1089 		*rp->sfas_syncoff = nexus->syncoff;
1090 		*rp->sfas_config3 = nexus->config3;
1091 
1092 		sfas_restore_pointers(dev);
1093 
1094 		nexus->status	= 0xFF;
1095 		dev->sc_msg_in[0] = 0xFF;
1096 		dev->sc_msg_in_len= 0;
1097 
1098 		dev->sc_led(dev, 1);
1099 
1100 		break;
1101 
1102 	case SFAS_NS_DATA_IN:
1103 	case SFAS_NS_DATA_OUT:
1104 		/* We have transferred data. */
1105 		if (dev->sc_dma_len)
1106 			if (dev->sc_cur_link < dev->sc_max_link) {
1107 				/*
1108 				 * Clean up DMA and at the same time get how
1109 				 * many bytes that were NOT transferred.
1110 				 */
1111 			  left = dev->sc_setup_dma(dev, 0, 0, SFAS_DMA_CLEAR);
1112 			  len  = dev->sc_dma_len;
1113 
1114 			  if (nexus->state == SFAS_NS_DATA_IN) {
1115 			    /*
1116 			     * If we were bumping we may have had an odd length
1117 			     * which means that there may be bytes left in the
1118 			     * fifo. We also need to move the data from the
1119 			     * bump buffer to the actual memory.
1120 			     */
1121 			    if (dev->sc_dma_buf == dev->sc_bump_pa)
1122 			    {
1123 			      while((*rp->sfas_fifo_flags&SFAS_FIFO_COUNT_MASK)
1124 				    && left)
1125 				dev->sc_bump_va[len-(left--)] = *rp->sfas_fifo;
1126 
1127 			      memcpy(dev->sc_buf, dev->sc_bump_va, len-left);
1128 			    }
1129 			  } else {
1130 			    /* Count any unsent bytes and flush them. */
1131 			    left+= *rp->sfas_fifo_flags & SFAS_FIFO_COUNT_MASK;
1132 			    *rp->sfas_command = SFAS_CMD_FLUSH_FIFO;
1133 			  }
1134 
1135 			  /*
1136 			   * Update pointers/length to reflect the transferred
1137 			   * data.
1138 			   */
1139 			  dev->sc_len -= len-left;
1140 			  dev->sc_buf += len-left;
1141 
1142 			  dev->sc_dma_buf = (char *)dev->sc_dma_buf + len-left;
1143 			  dev->sc_dma_len = left;
1144 
1145 			  dev->sc_dma_blk_ptr = (char *)dev->sc_dma_blk_ptr +
1146 				  len-left;
1147 			  dev->sc_dma_blk_len -= len-left;
1148 
1149 			  /*
1150 			   * If it was the end of a DMA block, we select the
1151 			   * next to begin with.
1152 			   */
1153 			  if (!dev->sc_dma_blk_len)
1154 			    dev->sc_cur_link++;
1155 			}
1156 		break;
1157 
1158 	case SFAS_NS_STATUS:
1159 		/*
1160 		 * If we were not sensing, grab the status byte. If we were
1161 		 * sensing and we got a bad status, let the user know.
1162 		 */
1163 
1164 		status = *rp->sfas_fifo;
1165 		msg = *rp->sfas_fifo;
1166 
1167 		nexus->status = status;
1168 		if (status != 0)
1169 			nexus->status = -1;
1170 
1171 		/*
1172 		 * Preload the command complete message. Handeled in
1173 		 * sfas_postaction.
1174 		 */
1175 		dev->sc_msg_in[0] = msg;
1176 		dev->sc_msg_in_len = 1;
1177 		nexus->flags |= SFAS_NF_HAS_MSG;
1178 		break;
1179 
1180 	default:
1181 		break;
1182 	}
1183 
1184 	return(0);
1185 }
1186 
1187 /*
1188  * Part three of the interrupt machine. Handle phase changes (and repeated
1189  * phase passes). We know that we have an active nexus here.
1190  */
1191 int
1192 sfas_postaction(struct sfas_softc *dev, sfas_regmap_p rp, struct nexus *nexus)
1193 {
1194 	int	i, len;
1195 	u_char	cmd;
1196 	short	offset, period;
1197 
1198 	cmd = 0;
1199 
1200 	switch(dev->sc_status & SFAS_STAT_PHASE_MASK) {
1201 	case SFAS_PHASE_DATA_OUT:
1202 	case SFAS_PHASE_DATA_IN:
1203 		if ((dev->sc_status & SFAS_STAT_PHASE_MASK) ==
1204 		    SFAS_PHASE_DATA_OUT)
1205 			nexus->state = SFAS_NS_DATA_OUT;
1206 		else
1207 			nexus->state = SFAS_NS_DATA_IN;
1208 
1209 		/* Make DMA ready to accept new data. Load active pointers
1210 		 * from the DMA block. */
1211 		dev->sc_setup_dma(dev, 0, 0, SFAS_DMA_CLEAR);
1212 		if (dev->sc_cur_link < dev->sc_max_link) {
1213 		  if (!dev->sc_dma_blk_len) {
1214 		    dev->sc_dma_blk_ptr = dev->sc_chain[dev->sc_cur_link].ptr;
1215 		    dev->sc_dma_blk_len = dev->sc_chain[dev->sc_cur_link].len;
1216 		    dev->sc_dma_blk_flg = dev->sc_chain[dev->sc_cur_link].flg;
1217 		  }
1218 
1219 		  /* We should use polled IO here. */
1220 		  if (dev->sc_dma_blk_flg == SFAS_CHAIN_PRG) {
1221 			dev->sc_ixfer(dev, nexus->xs->xs_control & XS_CTL_POLL);
1222 			dev->sc_cur_link++;
1223 			dev->sc_dma_len = 0;
1224 			break;
1225 		  }
1226 		  else if (dev->sc_dma_blk_flg == SFAS_CHAIN_BUMP)
1227 			len = dev->sc_dma_blk_len;
1228 		  else
1229 			len = dev->sc_need_bump(dev, dev->sc_dma_blk_ptr,
1230 						dev->sc_dma_blk_len);
1231 
1232 		  /*
1233 		   * If len != 0 we must bump the data, else we just DMA it
1234 		   * straight into memory.
1235 		   */
1236 		  if (len) {
1237 			dev->sc_dma_buf = dev->sc_bump_pa;
1238 			dev->sc_dma_len = len;
1239 
1240 			if (nexus->state == SFAS_NS_DATA_OUT)
1241 			  memcpy(dev->sc_bump_va, dev->sc_buf, dev->sc_dma_len);
1242 		  } else {
1243 			dev->sc_dma_buf = dev->sc_dma_blk_ptr;
1244 			dev->sc_dma_len = dev->sc_dma_blk_len;
1245 		  }
1246 
1247 		  /* Load DMA with address and length of transfer. */
1248 		  dev->sc_setup_dma(dev, dev->sc_dma_buf, dev->sc_dma_len,
1249 				    ((nexus->state == SFAS_NS_DATA_OUT) ?
1250 				     SFAS_DMA_WRITE : SFAS_DMA_READ));
1251 
1252 /*		  printf("Using DMA !!!!\n");*/
1253 		  cmd = SFAS_CMD_TRANSFER_INFO | SFAS_CMD_DMA;
1254 		} else {
1255 			/*
1256 			 * Hmmm, the unit wants more info than we have or has
1257 			 * more than we want. Let the chip handle that.
1258 			 */
1259 
1260 			*rp->sfas_tc_low = 0; /* was 256 but this does not make sense */
1261 			*rp->sfas_tc_mid = 1;
1262 			*rp->sfas_tc_high = 0;
1263 			cmd = SFAS_CMD_TRANSFER_PAD;
1264 		}
1265 		break;
1266 
1267 	case SFAS_PHASE_COMMAND:
1268 		/* The scsi unit wants the command, send it. */
1269 		nexus->state = SFAS_NS_SVC;
1270 
1271 		*rp->sfas_command = SFAS_CMD_FLUSH_FIFO;
1272 		for(i=0; i<5; i++);
1273 
1274 		for(i=0; i<nexus->clen; i++)
1275 			*rp->sfas_fifo = nexus->cbuf[i];
1276 		cmd = SFAS_CMD_TRANSFER_INFO;
1277 		break;
1278 
1279 	case SFAS_PHASE_STATUS:
1280 		/*
1281 		 * We've got status phase. Request status and command
1282 		 * complete message.
1283 		 */
1284 		nexus->state = SFAS_NS_STATUS;
1285 		cmd = SFAS_CMD_COMMAND_COMPLETE;
1286 		break;
1287 
1288 	case SFAS_PHASE_MESSAGE_OUT:
1289 		/*
1290 		 * Either the scsi unit wants us to send a message or we have
1291 		 * asked for it by seting the ATN bit.
1292 		 */
1293 		nexus->state = SFAS_NS_MSG_OUT;
1294 
1295 		*rp->sfas_command = SFAS_CMD_FLUSH_FIFO;
1296 
1297 		if (nexus->flags & SFAS_NF_DO_SDTR) {
1298 			/* Send a Synchronous Data Transfer Request. */
1299 
1300 			sfas_build_sdtrm(dev, nexus->period, nexus->offset);
1301 			nexus->flags |= SFAS_NF_SDTR_SENT;
1302 			nexus->flags &= ~SFAS_NF_DO_SDTR;
1303 		} else if (nexus->flags & SFAS_NF_RESET) {
1304 			/* Send a reset scsi unit message. */
1305 
1306 			dev->sc_msg_out[0] = 0x0C;
1307 			dev->sc_msg_out_len = 1;
1308 			nexus->state = SFAS_NS_RESET;
1309 			nexus->flags &= ~SFAS_NF_RESET;
1310 		} else if (dev->sc_msg_out_len == 0) {
1311 			/* Don't know what to send so we send a NOP message. */
1312 
1313 			dev->sc_msg_out[0] = 0x08;
1314 			dev->sc_msg_out_len = 1;
1315 		}
1316 
1317 		cmd = SFAS_CMD_TRANSFER_INFO;
1318 
1319 		for(i=0; i<dev->sc_msg_out_len; i++)
1320 			*rp->sfas_fifo = dev->sc_msg_out[i];
1321 		dev->sc_msg_out_len = 0;
1322 
1323 		break;
1324 
1325 	case SFAS_PHASE_MESSAGE_IN:
1326 		/* Receive a message from the scsi unit. */
1327 		nexus->state = SFAS_NS_MSG_IN;
1328 
1329 		while(!(nexus->flags & SFAS_NF_HAS_MSG)) {
1330 			*rp->sfas_command = SFAS_CMD_TRANSFER_INFO;
1331 			sfasiwait(dev);
1332 
1333 			dev->sc_msg_in[dev->sc_msg_in_len++] = *rp->sfas_fifo;
1334 
1335 			/* Check if we got all the bytes in the message. */
1336 			if (dev->sc_msg_in[0] >= 0x80)       ;
1337 			else if (dev->sc_msg_in[0] >= 0x30)  ;
1338 			else if (((dev->sc_msg_in[0] >= 0x20) &&
1339 				  (dev->sc_msg_in_len == 2)) ||
1340 				 ((dev->sc_msg_in[0] != 0x01) &&
1341 				  (dev->sc_msg_in_len == 1))) {
1342 				nexus->flags |= SFAS_NF_HAS_MSG;
1343 				break;
1344 			} else {
1345 			  if (dev->sc_msg_in_len >= 2)
1346 			    if ((dev->sc_msg_in[1]+2) == dev->sc_msg_in_len) {
1347 				nexus->flags |= SFAS_NF_HAS_MSG;
1348 				break;
1349 			    }
1350 			}
1351 
1352 			*rp->sfas_command = SFAS_CMD_MESSAGE_ACCEPTED;
1353 			sfasiwait(dev);
1354 
1355 			if ((dev->sc_status & SFAS_STAT_PHASE_MASK) !=
1356 			    SFAS_PHASE_MESSAGE_IN)
1357 				break;
1358 		}
1359 
1360 		cmd = SFAS_CMD_MESSAGE_ACCEPTED;
1361 		if (nexus->flags & SFAS_NF_HAS_MSG) {
1362 			/* We have a message. Decode it. */
1363 
1364 			switch(dev->sc_msg_in[0]) {
1365 			case 0x00:	/* COMMAND COMPLETE */
1366 				nexus->state = SFAS_NS_DONE;
1367 				break;
1368 			case 0x04:	/* DISCONNECT */
1369 				nexus->state = SFAS_NS_DISCONNECTING;
1370 				break;
1371 			case 0x02:	/* SAVE DATA POINTER */
1372 				sfas_save_pointers(dev);
1373 				break;
1374 			case 0x03:	/* RESTORE DATA POINTERS */
1375 				sfas_restore_pointers(dev);
1376 				break;
1377 			case 0x07:	/* MESSAGE REJECT */
1378 				/*
1379 				 * If we had sent a SDTR and we got a message
1380 				 * reject, the scsi docs say that we must go
1381 				 * to async transfer.
1382 				 */
1383 				if (nexus->flags & SFAS_NF_SDTR_SENT) {
1384 					nexus->flags &= ~SFAS_NF_SDTR_SENT;
1385 
1386 					nexus->config3 &= ~SFAS_CFG3_FASTSCSI;
1387 					nexus->syncper = 5;
1388 					nexus->syncoff = 0;
1389 
1390 					*rp->sfas_syncper = nexus->syncper;
1391 					*rp->sfas_syncoff = nexus->syncoff;
1392 					*rp->sfas_config3 = nexus->config3;
1393 				} else
1394 				/*
1395 				 * Something was rejected but we don't know
1396 				 * what! PANIC!
1397 				 */
1398 				  panic("sfasintr: Unknown message rejected!");
1399 				break;
1400 			case 0x08:	/* MO OPERATION */
1401 				break;
1402 			case 0x01:	/* EXTENDED MESSAGE */
1403 				switch(dev->sc_msg_in[2]) {
1404 				case 0x01:/* SYNC. DATA TRANSFER REQUEST */
1405 					/* Decode the SDTR message. */
1406 					period = 4*dev->sc_msg_in[3];
1407 					offset = dev->sc_msg_in[4];
1408 
1409 					/*
1410 					 * Make sure that the specs are within
1411 					 * chip limits. Note that if we
1412 					 * initiated the negotiation the specs
1413 					 * WILL be within chip limits. If it
1414 					 * was the scsi unit that initiated
1415 					 * the negotiation, the specs may be
1416 					 * to high.
1417 					 */
1418 					if (offset > 16)
1419 						offset = 16;
1420 					if ((period < 200) &&
1421 					    (dev->sc_clock_freq <= 25))
1422 						period = 200;
1423 
1424 					if (offset == 0)
1425 					       period = 5*dev->sc_clock_period;
1426 
1427 					nexus->syncper = period/
1428 							  dev->sc_clock_period;
1429 					nexus->syncoff = offset;
1430 
1431 					if (period < 200)
1432 					  nexus->config3 |= SFAS_CFG3_FASTSCSI;
1433 					else
1434 					  nexus->config3 &=~SFAS_CFG3_FASTSCSI;
1435 
1436 					nexus->flags |= SFAS_NF_SYNC_TESTED;
1437 
1438 					*rp->sfas_syncper = nexus->syncper;
1439 					*rp->sfas_syncoff = nexus->syncoff;
1440 					*rp->sfas_config3 = nexus->config3;
1441 
1442 					/*
1443 					 * Hmmm, it seems that the scsi unit
1444 					 * initiated sync negotiation, so lets
1445 					 * reply acording to scsi-2 standard.
1446 					 */
1447 					if (!(nexus->flags& SFAS_NF_SDTR_SENT))
1448 					{
1449 					  if ((dev->sc_config_flags &
1450 					       SFAS_NO_SYNCH) ||
1451 					      (dev->sc_config_flags &
1452 					       SFAS_NO_DMA) ||
1453 					      sfas_inhibit_sync[
1454 							nexus->lun_unit & 7]) {
1455 					          period = 200;
1456 					          offset = 0;
1457 					  }
1458 
1459 					  nexus->offset = offset;
1460 					  nexus->period = period;
1461 					  nexus->flags |= SFAS_NF_DO_SDTR;
1462 					  *rp->sfas_command = SFAS_CMD_SET_ATN;
1463 					}
1464 
1465 					nexus->flags &= ~SFAS_NF_SDTR_SENT;
1466 					break;
1467 
1468 				case 0x00: /* MODIFY DATA POINTERS */
1469 				case 0x02: /* EXTENDED IDENTIFY (SCSI-1) */
1470 				case 0x03: /* WIDE DATA TRANSFER REQUEST */
1471 			        default:
1472 					/* Reject any unhandeled messages. */
1473 
1474 					dev->sc_msg_out[0] = 0x07;
1475 					dev->sc_msg_out_len = 1;
1476 					*rp->sfas_command = SFAS_CMD_SET_ATN;
1477 					cmd = SFAS_CMD_MESSAGE_ACCEPTED;
1478 					break;
1479 				}
1480 				break;
1481 
1482 			default:
1483 				/* Reject any unhandeled messages. */
1484 
1485 				dev->sc_msg_out[0] = 0x07;
1486 				dev->sc_msg_out_len = 1;
1487 				*rp->sfas_command = SFAS_CMD_SET_ATN;
1488 				cmd = SFAS_CMD_MESSAGE_ACCEPTED;
1489 				break;
1490 			}
1491 			nexus->flags &= ~SFAS_NF_HAS_MSG;
1492 			dev->sc_msg_in_len = 0;
1493 		}
1494 		break;
1495 	default:
1496 		printf("SFASINTR: UNKNOWN PHASE! phase: %d\n",
1497 		       dev->sc_status & SFAS_STAT_PHASE_MASK);
1498 		dev->sc_led(dev, 0);
1499 		sfas_scsidone(dev, nexus->xs, -4);
1500 
1501 		return(-1);
1502 	}
1503 
1504 	if (cmd)
1505 		*rp->sfas_command = cmd;
1506 
1507 	return(0);
1508 }
1509 
1510 /*
1511  * Stub for interrupt machine.
1512  */
1513 void
1514 sfasintr(struct sfas_softc *dev)
1515 {
1516 	sfas_regmap_p	 rp;
1517 	struct nexus	*nexus;
1518 
1519 	rp = dev->sc_fas;
1520 
1521 	if (!sfas_pretests(dev, rp)) {
1522 
1523 		nexus = dev->sc_cur_nexus;
1524 		if (nexus == NULL)
1525 			nexus = dev->sc_sel_nexus;
1526 
1527 		if (nexus)
1528 			if (!sfas_midaction(dev, rp, nexus))
1529 				sfas_postaction(dev, rp, nexus);
1530 	}
1531 }
1532 
1533 /*
1534  * sfasicmd is used to perform IO when we can't use interrupts. sfasicmd
1535  * emulates the normal environment by waiting for the chip and calling
1536  * sfasintr.
1537  */
1538 void
1539 sfasicmd(struct sfas_softc *dev, struct sfas_pending *pendp)
1540 {
1541 	struct nexus	*nexus;
1542 
1543 	nexus = &dev->sc_nexus[pendp->xs->xs_periph->periph_target];
1544 
1545 	if (!sfasselect(dev, pendp, (char *)pendp->xs->cmd, pendp->xs->cmdlen,
1546 			(char *)pendp->xs->data, pendp->xs->datalen,
1547 			SFAS_SELECT_I))
1548 		panic("sfasicmd: Couldn't select unit");
1549 
1550 	while(nexus->state != SFAS_NS_FINISHED) {
1551 		sfasiwait(dev);
1552 		sfasintr(dev);
1553 	}
1554 
1555 	nexus->flags &= ~SFAS_NF_SYNC_TESTED;
1556 }
1557 
1558 
1559 #ifdef SFAS_DEBUG
1560 
1561 void
1562 dump_nexus(struct nexus *nexus)
1563 {
1564 	int loop;
1565 
1566 	printf("nexus=%08x\n", (u_int)nexus);
1567 	printf("scsi_fer=%08x\n", (u_int)nexus->xs);
1568 	printf("ID=%02x\n", nexus->ID);
1569 	printf("clen=%02x\n", nexus->clen);
1570 	printf("cbuf=");
1571 	for (loop = 0; loop< 14; ++loop)
1572 		printf(" %02x\n", nexus->cbuf[loop]);
1573 	printf("\n");
1574 	printf("DMA:\n");
1575 	for (loop = 0; loop < MAXCHAIN; ++loop)
1576 		printf("dma_chain: %08x %04x %04x\n", nexus->dma[loop].ptr,
1577 		    nexus->dma[loop].len, nexus->dma[loop].flg);
1578 	printf("\n");
1579 
1580 	printf("max_link=%d\n", nexus->max_link);
1581 	printf("cur_link=%d\n", nexus->cur_link);
1582 
1583 	printf("buf=%08x\n", (u_int)nexus->buf);
1584 	printf("len=%08x\n", nexus->len);
1585 	printf("dma_buf=%08x\n", (u_int)nexus->dma_buf);
1586 	printf("dma_len=%08x\n", nexus->dma_len);
1587 	printf("dma_blk_ptr=%08x\n", (u_int)nexus->dma_blk_ptr);
1588 	printf("dma_blk_len=%08x\n", nexus->dma_blk_len);
1589 	printf("dma_blk_flag=%08x\n", nexus->dma_blk_flg);
1590 	printf("state=%02x\n", nexus->state);
1591 	printf("flags=%04x\n", nexus->flags);
1592 	printf("period=%d\n", nexus->period);
1593 	printf("offset=%d\n", nexus->offset);
1594 	printf("syncper=%d\n", nexus->syncper);
1595 	printf("syncoff=%d\n", nexus->syncoff);
1596 	printf("config3=%02x\n", nexus->config3);
1597 	printf("lun_unit=%d\n", nexus->lun_unit);
1598 	printf("status=%02x\n", nexus->status);
1599 	printf("\n");
1600 }
1601 
1602 void
1603 dump_nexii(struct sfas_softc *sc)
1604 {
1605 	int loop;
1606 
1607 	for (loop = 0; loop < 8; ++loop) {
1608 		dump_nexus(&sc->sc_nexus[loop]);
1609 	}
1610 }
1611 
1612 void
1613 dump_sfassoftc(struct sfas_softc *sc)
1614 {
1615 	printf("sfassoftc @ 0x%08x\n", (u_int)sc);
1616 	printf("clock_freq = %d\n", sc->sc_clock_freq);
1617 	printf("timeout = %d\n", sc->sc_timeout);
1618 	printf("host_id = %d\n", sc->sc_host_id);
1619 	printf("config_flags = 0x%08x\n", sc->sc_config_flags);
1620 	printf("led_status = %d\n", sc->sc_led_status);
1621 
1622 	dump_nexii(sc);
1623 	printf("cur_nexus = 0x%08x\n", (u_int)sc->sc_cur_nexus);
1624 	printf("sel_nexus = 0x%08x\n", (u_int)sc->sc_sel_nexus);
1625 	printf("\n");
1626 }
1627 
1628 #endif	/* SFAS_DEBUG */
1629