xref: /netbsd-src/sys/arch/acorn32/podulebus/sfas.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*	$NetBSD: sfas.c,v 1.20 2009/05/16 16:40:58 cegger 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 1.20 2009/05/16 16:40:58 cegger 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 <arm/arm32/katelib.h>
104 #include <acorn32/podulebus/podulebus.h>
105 #include <acorn32/podulebus/sfasreg.h>
106 #include <acorn32/podulebus/sfasvar.h>
107 
108 void sfas_minphys(struct buf *);
109 void sfas_init_nexus(struct sfas_softc *, struct nexus *);
110 void sfasinitialize(struct sfas_softc *);
111 void sfas_scsi_request(struct scsipi_channel *, scsipi_adapter_req_t, void *);
112 void sfas_donextcmd(struct sfas_softc *, struct sfas_pending *);
113 void sfas_scsidone(struct sfas_softc *, struct scsipi_xfer *, int);
114 void sfasintr(struct sfas_softc *);
115 void sfasiwait(struct sfas_softc *);
116 void sfas_ixfer(void *, int);
117 void sfasreset(struct sfas_softc *, int);
118 int  sfasselect(struct sfas_softc *, struct sfas_pending *, unsigned char *,
119 		int, unsigned char *, int, int);
120 void sfasicmd(struct sfas_softc *, struct sfas_pending *);
121 void sfasgo(struct sfas_softc *, struct sfas_pending *);
122 void sfas_save_pointers(struct sfas_softc *);
123 void sfas_restore_pointers(struct sfas_softc *);
124 void sfas_build_sdtrm(struct sfas_softc *, int, int);
125 int sfas_select_unit(struct sfas_softc *, short);
126 struct nexus *sfas_arbitate_target(struct sfas_softc *, int);
127 void sfas_setup_nexus(struct sfas_softc *, struct nexus *,
128 		      struct sfas_pending *, unsigned char *, int,
129 		      unsigned char *, int, int);
130 int sfas_pretests(struct sfas_softc *, sfas_regmap_p);
131 int sfas_midaction(struct sfas_softc *, sfas_regmap_p, struct nexus *);
132 int sfas_postaction(struct sfas_softc *, sfas_regmap_p, struct nexus *);
133 
134 /*
135  * Initialize these to make 'em patchable. Defaults to enable sync and discon.
136  */
137 u_char	sfas_inhibit_sync[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
138 u_char	sfas_inhibit_disc[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
139 
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 	u_int		*pte;
181 	int		 i;
182 
183 	dev->sc_led_status = 0;
184 
185 	TAILQ_INIT(&dev->sc_xs_pending);
186 	TAILQ_INIT(&dev->sc_xs_free);
187 
188 /*
189  * Initialize the sfas_pending structs and link them into the free list. We
190  * have to set vm_link_data.pages to 0 or the vm FIX won't work.
191  */
192 	for(i=0; i<MAXPENDING; i++) {
193 		TAILQ_INSERT_TAIL(&dev->sc_xs_free, &dev->sc_xs_store[i],
194 				  link);
195 	}
196 
197 /*
198  * Calculate the correct clock conversion factor 2 <= factor <= 8, i.e. set
199  * the factor to clock_freq / 5 (int).
200  */
201 	if (dev->sc_clock_freq <= 10)
202 		dev->sc_clock_conv_fact = 2;
203 	if (dev->sc_clock_freq <= 40)
204 		dev->sc_clock_conv_fact = 2+((dev->sc_clock_freq-10)/5);
205 	else
206 		panic("sfasinitialize: Clock frequence too high");
207 
208 /* Setup and save the basic configuration registers */
209 	dev->sc_config1 = (dev->sc_host_id & SFAS_CFG1_BUS_ID_MASK);
210 	dev->sc_config2 = SFAS_CFG2_FEATURES_ENABLE;
211 	dev->sc_config3 = (dev->sc_clock_freq > 25 ? SFAS_CFG3_FASTCLK : 0);
212 
213 /* Precalculate timeout value and clock period. */
214 /* Ekkk ... floating point in the kernel !!!! */
215 /*	dev->sc_timeout_val  = 1+dev->sc_timeout*dev->sc_clock_freq/
216 				 (7.682*dev->sc_clock_conv_fact);*/
217 	dev->sc_timeout_val  = 1+dev->sc_timeout*dev->sc_clock_freq/
218 				 ((7682*dev->sc_clock_conv_fact)/1000);
219 	dev->sc_clock_period = 1000/dev->sc_clock_freq;
220 
221 	sfasreset(dev, 1 | 2);	/* Reset Chip and Bus */
222 
223 	dev->sc_units_disconnected = 0;
224 	dev->sc_msg_in_len = 0;
225 	dev->sc_msg_out_len = 0;
226 
227 	dev->sc_flags = 0;
228 
229 	for(i=0; i<8; i++)
230 		sfas_init_nexus(dev, &dev->sc_nexus[i]);
231 
232 	if (dev->sc_ixfer == NULL)
233 		dev->sc_ixfer = sfas_ixfer;
234 
235 /*
236  * Setup bump buffer.
237  */
238 	dev->sc_bump_va = (u_char *)uvm_km_alloc(kernel_map, dev->sc_bump_sz, 0,
239 	    UVM_KMF_WIRED | UVM_KMF_ZERO);
240 	(void) pmap_extract(pmap_kernel(), (vaddr_t)dev->sc_bump_va,
241 	    (paddr_t *)&dev->sc_bump_pa);
242 
243 /*
244  * Setup pages to noncachable, that way we don't have to flush the cache
245  * every time we need "bumped" transfer.
246  */
247 	pte = vtopte((vaddr_t) dev->sc_bump_va);
248 	*pte &= ~(L2_C | L2_B);
249 	PTE_SYNC(pte);
250 	cpu_tlb_flushD();
251 	cpu_dcache_wbinv_range((vm_offset_t)dev->sc_bump_va, PAGE_SIZE);
252 
253 	printf(" dmabuf V0x%08x P0x%08x", (u_int)dev->sc_bump_va, (u_int)dev->sc_bump_pa);
254 }
255 
256 
257 /*
258  * used by specific sfas controller
259  */
260 void
261 sfas_scsi_request(struct scsipi_channel *chan, scsipi_adapter_req_t req,
262 								void *arg)
263 {
264 	struct scsipi_xfer *xs;
265 	struct sfas_softc	*dev = (void *)chan->chan_adapter->adapt_dev;
266 	struct scsipi_periph	*periph;
267 	struct sfas_pending	*pendp;
268 	int			 flags, s, target;
269 
270 	switch (req) {
271 	case ADAPTER_REQ_RUN_XFER:
272 		xs = arg;
273 		periph = xs->xs_periph;
274 		flags = xs->xs_control;
275 		target = periph->periph_target;
276 
277 		if (flags & XS_CTL_DATA_UIO)
278 			panic("sfas: scsi data uio requested");
279 
280 		if ((flags & XS_CTL_POLL) && (dev->sc_flags & SFAS_ACTIVE))
281 			panic("sfas_scsicmd: busy");
282 
283 /* Get hold of a sfas_pending block. */
284 		s = splbio();
285 		pendp = dev->sc_xs_free.tqh_first;
286 		if (pendp == NULL) {
287 			xs->error = XS_RESOURCE_SHORTAGE;
288 			scsipi_done(xs);
289 			splx(s);
290 			return;
291 		}
292 		TAILQ_REMOVE(&dev->sc_xs_free, pendp, link);
293 		pendp->xs = xs;
294 		splx(s);
295 
296 
297 /* If the chip if busy OR the unit is busy, we have to wait for out turn. */
298 		if ((dev->sc_flags & SFAS_ACTIVE) ||
299 		    (dev->sc_nexus[target].flags & SFAS_NF_UNIT_BUSY)) {
300 			s = splbio();
301 			TAILQ_INSERT_TAIL(&dev->sc_xs_pending, pendp, link);
302 			splx(s);
303 		} else
304 			sfas_donextcmd(dev, pendp);
305 
306 		return;
307 
308 	case ADAPTER_REQ_GROW_RESOURCES:
309 	case ADAPTER_REQ_SET_XFER_MODE:
310 		/* XXX Not supported. */
311 		return;
312 	}
313 }
314 
315 /*
316  * Actually select the unit, whereby the whole scsi-process is started.
317  */
318 void
319 sfas_donextcmd(struct sfas_softc *dev, struct sfas_pending *pendp)
320 {
321 	int	s;
322 
323 /*
324  * Special case for scsi unit reset. I think this is waterproof. We first
325  * select the unit during splbio. We then cycle through the generated
326  * interrupts until the interrupt routine signals that the unit has
327  * acknowledged the reset. After that we have to wait a reset to select
328  * delay before anything else can happend.
329  */
330 	if (pendp->xs->xs_control & XS_CTL_RESET) {
331 		struct nexus	*nexus;
332 
333 		s = splbio();
334 		while(!sfasselect(dev, pendp, 0, 0, 0, 0, SFAS_SELECT_K)) {
335 			splx(s);
336 			delay(10);
337 			s = splbio();
338 		}
339 
340 		nexus = dev->sc_cur_nexus;
341 		while(nexus->flags & SFAS_NF_UNIT_BUSY) {
342 			sfasiwait(dev);
343 			sfasintr(dev);
344 		}
345 
346 		nexus->flags |= SFAS_NF_UNIT_BUSY;
347 		splx(s);
348 
349 		sfasreset(dev, 0);
350 
351 		s = splbio();
352 		nexus->flags &= ~SFAS_NF_UNIT_BUSY;
353 		splx(s);
354 	}
355 
356 /*
357  * If we are polling, go to splbio and perform the command, else we poke
358  * the scsi-bus via sfasgo to get the interrupt machine going.
359  */
360 	if (pendp->xs->xs_control & XS_CTL_POLL) {
361 		s = splbio();
362 		sfasicmd(dev, pendp);
363 		TAILQ_INSERT_TAIL(&dev->sc_xs_free, pendp, link);
364 		splx(s);
365 	} else {
366 		sfasgo(dev, pendp);
367 	}
368 }
369 
370 void
371 sfas_scsidone(struct sfas_softc *dev, struct scsipi_xfer *xs, int stat)
372 {
373 	struct sfas_pending	*pendp;
374 	int			 s;
375 
376 	xs->status = stat;
377 
378 	if (stat == 0)
379 		xs->resid = 0;
380 	else {
381 		switch(stat) {
382 		case SCSI_CHECK:
383 		case SCSI_BUSY:
384 			xs->error = XS_BUSY;
385 			break;
386 		case -1:
387 			xs->error = XS_DRIVER_STUFFUP;
388 			QPRINTF(("sfas_scsicmd() bad %x\n", stat));
389 			break;
390 		default:
391 			xs->error = XS_TIMEOUT;
392 			break;
393 		}
394 	}
395 
396 /* Steal the next command from the queue so that one unit can't hog the bus. */
397 	s = splbio();
398 	pendp = dev->sc_xs_pending.tqh_first;
399 	while(pendp) {
400 		if (!(dev->sc_nexus[pendp->xs->xs_periph->periph_target].flags &
401 		      SFAS_NF_UNIT_BUSY))
402 			break;
403 		pendp = pendp->link.tqe_next;
404 	}
405 
406 	if (pendp != NULL) {
407 		TAILQ_REMOVE(&dev->sc_xs_pending, pendp, link);
408 	}
409 
410 	splx(s);
411 	scsipi_done(xs);
412 
413 	if (pendp)
414 		sfas_donextcmd(dev, pendp);
415 }
416 
417 /*
418  * There are two kinds of reset:
419  *  1) CHIP-bus reset. This also implies a SCSI-bus reset.
420  *  2) SCSI-bus reset.
421  * After the appropriate resets have been performed we wait a reset to select
422  * delay time.
423  */
424 void
425 sfasreset(struct sfas_softc *dev, int how)
426 {
427 	sfas_regmap_p	rp;
428 	int		i, s;
429 
430 	rp = dev->sc_fas;
431 
432 	if (how & 1) {
433 		for(i=0; i<8; i++)
434 			sfas_init_nexus(dev, &dev->sc_nexus[i]);
435 
436 		*rp->sfas_command = SFAS_CMD_RESET_CHIP;
437 		delay(1);
438 		*rp->sfas_command = SFAS_CMD_NOP;
439 
440 		*rp->sfas_config1 = dev->sc_config1;
441 		*rp->sfas_config2 = dev->sc_config2;
442 		*rp->sfas_config3 = dev->sc_config3;
443 		*rp->sfas_timeout = dev->sc_timeout_val;
444 		*rp->sfas_clkconv = dev->sc_clock_conv_fact &
445 					SFAS_CLOCK_CONVERSION_MASK;
446 	}
447 
448 	if (how & 2) {
449 		for(i=0; i<8; i++)
450 			sfas_init_nexus(dev, &dev->sc_nexus[i]);
451 
452 		s = splbio();
453 
454 		*rp->sfas_command = SFAS_CMD_RESET_SCSI_BUS;
455 		delay(100);
456 
457 /* Skip interrupt generated by RESET_SCSI_BUS */
458 		while(*rp->sfas_status & SFAS_STAT_INTERRUPT_PENDING) {
459 			dev->sc_status = *rp->sfas_status;
460 			dev->sc_interrupt = *rp->sfas_interrupt;
461 
462 			delay(100);
463 		}
464 
465 		dev->sc_status = *rp->sfas_status;
466 		dev->sc_interrupt = *rp->sfas_interrupt;
467 
468 		splx(s);
469 	}
470 
471 	if (dev->sc_config_flags & SFAS_SLOW_START)
472 		delay(4*250000); /* RESET to SELECT DELAY*4 for slow devices */
473 	else
474 		delay(250000);	 /* RESET to SELECT DELAY */
475 }
476 
477 /*
478  * Save active data pointers to the nexus block currently active.
479  */
480 void
481 sfas_save_pointers(struct sfas_softc *dev)
482 {
483 	struct nexus	*nx;
484 
485 	nx = dev->sc_cur_nexus;
486 	if (nx) {
487 		nx->cur_link	= dev->sc_cur_link;
488 		nx->max_link	= dev->sc_max_link;
489 		nx->buf		= dev->sc_buf;
490 		nx->len		= dev->sc_len;
491 		nx->dma_len	= dev->sc_dma_len;
492 		nx->dma_buf	= dev->sc_dma_buf;
493 		nx->dma_blk_flg	= dev->sc_dma_blk_flg;
494 		nx->dma_blk_len	= dev->sc_dma_blk_len;
495 		nx->dma_blk_ptr	= dev->sc_dma_blk_ptr;
496 	}
497 }
498 
499 /*
500  * Restore data pointers from the currently active nexus block.
501  */
502 void
503 sfas_restore_pointers(struct sfas_softc *dev)
504 {
505 	struct nexus	*nx;
506 
507 	nx = dev->sc_cur_nexus;
508 	if (nx) {
509 		dev->sc_cur_link    = nx->cur_link;
510 		dev->sc_max_link    = nx->max_link;
511 		dev->sc_buf	    = nx->buf;
512 		dev->sc_len	    = nx->len;
513 		dev->sc_dma_len	    = nx->dma_len;
514 		dev->sc_dma_buf	    = nx->dma_buf;
515 		dev->sc_dma_blk_flg = nx->dma_blk_flg;
516 		dev->sc_dma_blk_len = nx->dma_blk_len;
517 		dev->sc_dma_blk_ptr = nx->dma_blk_ptr;
518 		dev->sc_chain	    = nx->dma;
519 		dev->sc_unit	    = (nx->lun_unit & 0x0F);
520 		dev->sc_lun	    = (nx->lun_unit & 0xF0) >> 4;
521 	}
522 }
523 
524 /*
525  * sfasiwait is used during interrupt and polled IO to wait for an event from
526  * the FAS chip. This function MUST NOT BE CALLED without interrupt disabled.
527  */
528 void
529 sfasiwait(struct sfas_softc *dev)
530 {
531 	sfas_regmap_p	rp;
532 
533 /*
534  * If SFAS_DONT_WAIT is set, we have already grabbed the interrupt info
535  * elsewhere. So we don't have to wait for it.
536  */
537 	if (dev->sc_flags & SFAS_DONT_WAIT) {
538 		dev->sc_flags &= ~SFAS_DONT_WAIT;
539 		return;
540 	}
541 
542 	rp = dev->sc_fas;
543 
544 /* Wait for FAS chip to signal an interrupt. */
545 	while(!(*rp->sfas_status & SFAS_STAT_INTERRUPT_PENDING))
546 		delay(1);
547 
548 /* Grab interrupt info from chip. */
549 	dev->sc_status = *rp->sfas_status;
550 	dev->sc_interrupt = *rp->sfas_interrupt;
551 	if (dev->sc_interrupt & SFAS_INT_RESELECTED) {
552 		dev->sc_resel[0] = *rp->sfas_fifo;
553 		dev->sc_resel[1] = *rp->sfas_fifo;
554 	}
555 }
556 
557 /*
558  * Transfer info to/from device. sfas_ixfer uses polled IO+sfasiwait so the
559  * rules that apply to sfasiwait also applies here.
560  */
561 void
562 sfas_ixfer(void *v, int polling)
563 {
564 	struct sfas_softc *dev = v;
565 	sfas_regmap_p	 rp;
566 	u_char		*buf;
567 	int		 len, mode, phase;
568 
569 	rp = dev->sc_fas;
570 	buf = dev->sc_buf;
571 	len = dev->sc_len;
572 
573 /*
574  * Decode the scsi phase to determine whether we are reading or writing.
575  * mode == 1 => READ, mode == 0 => WRITE
576  */
577 	phase = dev->sc_status & SFAS_STAT_PHASE_MASK;
578 	mode = (phase == SFAS_PHASE_DATA_IN);
579 
580 	while(len && ((dev->sc_status & SFAS_STAT_PHASE_MASK) == phase))
581 		if (mode) {
582 			*rp->sfas_command = SFAS_CMD_TRANSFER_INFO;
583 
584 			sfasiwait(dev);
585 
586 			*buf++ = *rp->sfas_fifo;
587 			len--;
588 		} else {
589 			len--;
590 			*rp->sfas_fifo = *buf++;
591 			*rp->sfas_command = SFAS_CMD_TRANSFER_INFO;
592 
593 			sfasiwait(dev);
594 		}
595 
596 /* Update buffer pointers to reflect the sent/received data. */
597 	dev->sc_buf = buf;
598 	dev->sc_len = len;
599 
600 /*
601  * Since the last sfasiwait will be a phase-change, we can't wait for it
602  * again later, so we have to signal that.
603  * Since this may be called from an interrupt initiated routine then we
604  * must call sfasintr again to avoid losing an interrupt. Phew!
605  */
606 	if(polling)
607 		dev->sc_flags |= SFAS_DONT_WAIT;
608 	else
609 		sfasintr(dev);
610 }
611 
612 /*
613  * Build a Synchronous Data Transfer Request message
614  */
615 void
616 sfas_build_sdtrm(struct sfas_softc *dev, int period, int offset)
617 {
618 	dev->sc_msg_out[0] = 0x01;
619 	dev->sc_msg_out[1] = 0x03;
620 	dev->sc_msg_out[2] = 0x01;
621 	dev->sc_msg_out[3] = period/4;
622 	dev->sc_msg_out[4] = offset;
623 	dev->sc_msg_out_len= 5;
624 }
625 
626 /*
627  * Arbitate the scsi bus and select the unit
628  */
629 int
630 sfas_select_unit(struct sfas_softc *dev, short target)
631 {
632 	sfas_regmap_p	 rp;
633 	struct nexus	*nexus;
634 	int		 s, retcode, i;
635 	u_char		 cmd;
636 
637 	s = splbio();	/* Do this at splbio so that we won't be disturbed. */
638 
639 	retcode = 0;
640 
641 	nexus = &dev->sc_nexus[target];
642 
643 /*
644  * Check if the chip is busy. If not the we mark it as so and hope that nobody
645  * reselects us until we have grabbed the bus.
646  */
647 	if (!(dev->sc_flags & SFAS_ACTIVE) && !dev->sc_sel_nexus) {
648 		dev->sc_flags |= SFAS_ACTIVE;
649 
650 		rp = dev->sc_fas;
651 
652 		*rp->sfas_syncper = nexus->syncper;
653 		*rp->sfas_syncoff = nexus->syncoff;
654 		*rp->sfas_config3 = nexus->config3;
655 
656 		*rp->sfas_config1 = dev->sc_config1;
657 		*rp->sfas_timeout = dev->sc_timeout_val;
658 		*rp->sfas_dest_id = target;
659 
660 /* If nobody has stolen the bus, we can send a select command to the chip. */
661 		if (!(*rp->sfas_status & SFAS_STAT_INTERRUPT_PENDING)) {
662 			*rp->sfas_fifo = nexus->ID;
663 			if ((nexus->flags & (SFAS_NF_DO_SDTR | SFAS_NF_RESET))
664 			    || (dev->sc_msg_out_len != 0))
665 				cmd = SFAS_CMD_SEL_ATN_STOP;
666 			else {
667 				for(i=0; i<nexus->clen; i++)
668 					*rp->sfas_fifo = nexus->cbuf[i];
669 
670 				cmd = SFAS_CMD_SEL_ATN;
671 			}
672 
673 			dev->sc_sel_nexus = nexus;
674 
675 			*rp->sfas_command = cmd;
676 			retcode = 1;
677 			nexus->flags &= ~SFAS_NF_RETRY_SELECT;
678 		} else
679 			nexus->flags |= SFAS_NF_RETRY_SELECT;
680 	} else
681 		nexus->flags |= SFAS_NF_RETRY_SELECT;
682 
683 	splx(s);
684 	return(retcode);
685 }
686 
687 /*
688  * Grab the nexus if available else return 0.
689  */
690 struct nexus *
691 sfas_arbitate_target(struct sfas_softc *dev, int target)
692 {
693 	struct nexus	*nexus;
694 	int		 s;
695 
696 /*
697  * This is realy simple. Raise interrupt level to splbio. Grab the nexus and
698  * leave.
699  */
700 	nexus = &dev->sc_nexus[target];
701 
702 	s = splbio();
703 
704 	if (nexus->flags & SFAS_NF_UNIT_BUSY)
705 		nexus = 0;
706 	else
707 		nexus->flags |= SFAS_NF_UNIT_BUSY;
708 
709 	splx(s);
710 	return(nexus);
711 }
712 
713 /*
714  * Setup a nexus for use. Initializes command, buffer pointers and DMA chain.
715  */
716 void
717 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)
718 {
719 	char	sync, target, lun;
720 
721 	target = pendp->xs->xs_periph->periph_target;
722 	lun    = pendp->xs->xs_periph->periph_lun;
723 
724 /*
725  * Adopt mode to reflect the config flags.
726  * If we can't use DMA we can't use synch transfer. Also check the
727  * sfas_inhibit_xxx[target] flags.
728  */
729 	if ((dev->sc_config_flags & (SFAS_NO_SYNCH | SFAS_NO_DMA)) ||
730 	    sfas_inhibit_sync[(int)target])
731 		mode &= ~SFAS_SELECT_S;
732 
733 	if ((dev->sc_config_flags & SFAS_NO_RESELECT) ||
734 	    sfas_inhibit_disc[(int)target])
735 		mode &= ~SFAS_SELECT_R;
736 
737 	nexus->xs		= pendp->xs;
738 
739 /* Setup the nexus struct. */
740 	nexus->ID	   = ((mode & SFAS_SELECT_R) ? 0xC0 : 0x80) | lun;
741 	nexus->clen	   = clen;
742 	memcpy(nexus->cbuf, cbuf, nexus->clen);
743 	nexus->cbuf[1] |= lun << 5;		/* Fix the lun bits */
744 	nexus->cur_link	   = 0;
745 	nexus->dma_len	   = 0;
746 	nexus->dma_buf	   = 0;
747 	nexus->dma_blk_len = 0;
748 	nexus->dma_blk_ptr = 0;
749 	nexus->len	   = len;
750 	nexus->buf	   = buf;
751 	nexus->lun_unit	   = (lun << 4) | target;
752 	nexus->state	   = SFAS_NS_SELECTED;
753 
754 /* We must keep these flags. All else must be zero. */
755 	nexus->flags	  &= SFAS_NF_UNIT_BUSY
756 			   | SFAS_NF_SYNC_TESTED | SFAS_NF_SELECT_ME;
757 
758 	if (mode & SFAS_SELECT_I)
759 		nexus->flags |= SFAS_NF_IMMEDIATE;
760 	if (mode & SFAS_SELECT_K)
761 		nexus->flags |= SFAS_NF_RESET;
762 
763 	sync  = ((mode & SFAS_SELECT_S) ? 1 : 0);
764 
765 /* We can't use sync during polled IO. */
766 	if (sync && (mode & SFAS_SELECT_I))
767 		sync = 0;
768 
769 	if (!sync &&
770 	    ((nexus->flags & SFAS_NF_SYNC_TESTED) && (nexus->offset != 0))) {
771 		/*
772 		 * If the scsi unit is set to synch transfer and we don't want
773 		 * that, we have to renegotiate.
774 		 */
775 
776 		nexus->flags |= SFAS_NF_DO_SDTR;
777 		nexus->period = 200;
778 		nexus->offset = 0;
779 	} else if (sync && !(nexus->flags & SFAS_NF_SYNC_TESTED)) {
780 		/*
781 		 * If the scsi unit is not set to synch transfer and we want
782 		 * that, we have to negotiate. This should realy base the
783 		 * period on the clock frequence rather than just check if
784 		 * >25 MHz
785 		 */
786 
787 		nexus->flags |= SFAS_NF_DO_SDTR;
788 		nexus->period = ((dev->sc_clock_freq>25) ? 100 : 200);
789 		nexus->offset = 8;
790 
791 		/* If the user has a long cable, we want to limit the period */
792 		if ((nexus->period == 100) &&
793 		    (dev->sc_config_flags & SFAS_SLOW_CABLE))
794 			nexus->period = 200;
795 	}
796 
797 /*
798  * Fake a DMA-block for polled IO. This way we can use the same code to handle
799  * reselection. Much nicer this way.
800  */
801 	if ((mode & SFAS_SELECT_I) || (dev->sc_config_flags & SFAS_NO_DMA)) {
802 		nexus->dma[0].ptr = buf;
803 		nexus->dma[0].len = len;
804 		nexus->dma[0].flg = SFAS_CHAIN_PRG;
805 		nexus->max_link   = 1;
806 	} else {
807 		nexus->max_link = dev->sc_build_dma_chain(dev, nexus->dma,
808 							  buf, len);
809 	}
810 
811 /* Flush the caches. */
812 
813 	if (len && !(mode & SFAS_SELECT_I))
814 		cpu_dcache_wbinv_range((vm_offset_t)buf, len);
815 }
816 
817 int
818 sfasselect(struct sfas_softc *dev, struct sfas_pending *pendp, unsigned char *cbuf, int clen, unsigned char *buf, int len, int mode)
819 {
820 	struct nexus	*nexus;
821 
822 /* Get the nexus struct. */
823 	nexus = sfas_arbitate_target(dev, pendp->xs->xs_periph->periph_target);
824 	if (nexus == NULL)
825 		return(0);
826 
827 /* Setup the nexus struct. */
828 	sfas_setup_nexus(dev, nexus, pendp, cbuf, clen, buf, len, mode);
829 
830 /* Post it to the interrupt machine. */
831 	sfas_select_unit(dev, pendp->xs->xs_periph->periph_target);
832 
833 	return(1);
834 }
835 
836 void
837 sfasgo(struct sfas_softc *dev, struct sfas_pending *pendp)
838 {
839 	int	 s;
840 	char	*buf;
841 
842 	buf    = pendp->xs->data;
843 
844 	if (sfasselect(dev, pendp, (char *)pendp->xs->cmd, pendp->xs->cmdlen,
845 		      buf, pendp->xs->datalen, SFAS_SELECT_RS)) {
846 		/*
847 		 * We got the command going so the sfas_pending struct is now
848 		 * free to reuse.
849 		 */
850 
851 		s = splbio();
852 		TAILQ_INSERT_TAIL(&dev->sc_xs_free, pendp, link);
853 		splx(s);
854 	} else {
855 		/*
856 		 * We couldn't make the command fly so we have to wait. The
857 		 * struct MUST be inserted at the head to keep the order of
858 		 * the commands.
859 		 */
860 
861 		s = splbio();
862 		TAILQ_INSERT_HEAD(&dev->sc_xs_pending, pendp, link);
863 		splx(s);
864 	}
865 
866 	return;
867 }
868 
869 /*
870  * Part one of the interrupt machine. Error checks and reselection test.
871  * We don't know if we have an active nexus here!
872  */
873 int
874 sfas_pretests(struct sfas_softc *dev, sfas_regmap_p rp)
875 {
876 	struct nexus	*nexus;
877 	int		 i, s;
878 
879 	if (dev->sc_interrupt & SFAS_INT_SCSI_RESET_DETECTED) {
880 		/*
881 		 * Cleanup and notify user. Lets hope that this is all we
882 		 * have to do
883 		 */
884 
885 		for(i=0; i<8; i++) {
886 			if (dev->sc_nexus[i].xs)
887 				sfas_scsidone(dev, dev->sc_nexus[i].xs, -2);
888 
889 			sfas_init_nexus(dev, &dev->sc_nexus[i]);
890 		}
891 		printf("sfasintr: SCSI-RESET detected!");
892 		return(-1);
893 	}
894 
895 	if (dev->sc_interrupt & SFAS_INT_ILLEGAL_COMMAND) {
896 		/* Something went terrible wrong! Dump some data and panic! */
897 
898 		printf("FIFO:");
899 		while(*rp->sfas_fifo_flags & SFAS_FIFO_COUNT_MASK)
900 			printf(" %x", *rp->sfas_fifo);
901 		printf("\n");
902 
903 		printf("CMD: %x\n", *rp->sfas_command);
904 		panic("sfasintr: ILLEGAL COMMAND!");
905 	}
906 
907 	if (dev->sc_interrupt & SFAS_INT_RESELECTED) {
908 		/* We were reselected. Set the chip as busy */
909 
910 		s = splbio();
911 		dev->sc_flags |= SFAS_ACTIVE;
912 		if (dev->sc_sel_nexus) {
913 			dev->sc_sel_nexus->flags |= SFAS_NF_SELECT_ME;
914 			dev->sc_sel_nexus = 0;
915 		}
916 		splx(s);
917 
918 		if (dev->sc_units_disconnected) {
919 			/* Find out who reselected us. */
920 
921 			dev->sc_resel[0] &= ~(1<<dev->sc_host_id);
922 
923 			for(i=0; i<8; i++)
924 				if (dev->sc_resel[0] & (1<<i))
925 					break;
926 
927 			if (i == 8)
928 				panic("Illegal reselection!");
929 
930 			if (dev->sc_nexus[i].state == SFAS_NS_DISCONNECTED) {
931 				/*
932 				 * This unit had disconnected, so we reconnect
933 				 * it.
934 				 */
935 
936 				dev->sc_cur_nexus = &dev->sc_nexus[i];
937 				nexus = dev->sc_cur_nexus;
938 
939 				*rp->sfas_syncper = nexus->syncper;
940 				*rp->sfas_syncoff = nexus->syncoff;
941 				*rp->sfas_config3 = nexus->config3;
942 
943 				*rp->sfas_dest_id = i & 7;
944 
945 				dev->sc_units_disconnected--;
946 				dev->sc_msg_in_len= 0;
947 
948 				/* Restore active pointers. */
949 				sfas_restore_pointers(dev);
950 
951 				nexus->state = SFAS_NS_RESELECTED;
952 
953 				*rp->sfas_command = SFAS_CMD_MESSAGE_ACCEPTED;
954 
955 				return(1);
956 			}
957 		}
958 
959 		/* Somehow we got an illegal reselection. Dump and panic. */
960 		printf("sfasintr: resel[0] %x resel[1] %x disconnected %d\n",
961 		       dev->sc_resel[0], dev->sc_resel[1],
962 		       dev->sc_units_disconnected);
963 		panic("sfasintr: Unexpected reselection!");
964 	}
965 
966 	return(0);
967 }
968 
969 /*
970  * Part two of the interrupt machine. Handle disconnection and post command
971  * processing. We know that we have an active nexus here.
972  */
973 int
974 sfas_midaction(struct sfas_softc *dev, sfas_regmap_p rp, struct nexus *nexus)
975 {
976 	int	i, left, len, s;
977 	u_char	status, msg;
978 
979 	if (dev->sc_interrupt & SFAS_INT_DISCONNECT) {
980 		s = splbio();
981 		dev->sc_cur_nexus = 0;
982 
983 		/* Mark chip as busy and clean up the chip FIFO. */
984 		dev->sc_flags &= ~SFAS_ACTIVE;
985 		*rp->sfas_command = SFAS_CMD_FLUSH_FIFO;
986 
987 		/* Let the nexus state reflect what we have to do. */
988 		switch(nexus->state) {
989 		case SFAS_NS_SELECTED:
990 			dev->sc_sel_nexus = 0;
991 			nexus->flags &= ~SFAS_NF_SELECT_ME;
992 
993 			/*
994 			 * We were trying to select the unit. Probably no unit
995 			 * at this ID.
996 			 */
997 			nexus->xs->resid = dev->sc_len;
998 
999 			nexus->status = -2;
1000 			nexus->flags &= ~SFAS_NF_UNIT_BUSY;
1001 			nexus->state = SFAS_NS_FINISHED;
1002 			break;
1003 
1004 		case SFAS_NS_DONE:
1005 			/* All done. */
1006 			nexus->xs->resid = dev->sc_len;
1007 
1008 			nexus->flags &= ~SFAS_NF_UNIT_BUSY;
1009 			nexus->state  = SFAS_NS_FINISHED;
1010 			dev->sc_led(dev, 0);
1011 			break;
1012 
1013 		case SFAS_NS_DISCONNECTING:
1014 			/*
1015 			 * We have received a DISCONNECT message, so we are
1016 			 * doing a normal disconnection.
1017 			 */
1018 			nexus->state = SFAS_NS_DISCONNECTED;
1019 
1020 			dev->sc_units_disconnected++;
1021 			break;
1022 
1023 		case SFAS_NS_RESET:
1024 			/*
1025 			 * We were reseting this SCSI-unit. Clean up the
1026 			 * nexus struct.
1027 			 */
1028 			dev->sc_led(dev, 0);
1029 			sfas_init_nexus(dev, nexus);
1030 			break;
1031 
1032 		default:
1033 			/*
1034 			 * Unexpected disconnection! Cleanup and exit. This
1035 			 * shouldn't cause any problems.
1036 			 */
1037 			printf("sfasintr: Unexpected disconnection\n");
1038 			printf("sfasintr: u %x s %d p %d f %x c %x\n",
1039 			       nexus->lun_unit, nexus->state,
1040 			       dev->sc_status & SFAS_STAT_PHASE_MASK,
1041 			       nexus->flags, nexus->cbuf[0]);
1042 
1043 			nexus->xs->resid = dev->sc_len;
1044 
1045 			nexus->flags &= ~SFAS_NF_UNIT_BUSY;
1046 			nexus->state = SFAS_NS_FINISHED;
1047 			nexus->status = -3;
1048 
1049 			dev->sc_led(dev, 0);
1050 			break;
1051 		}
1052 
1053 		/*
1054 		 * If we have disconnected units, we MUST enable reselection
1055 		 * within 250ms.
1056 		 */
1057 		if (dev->sc_units_disconnected &&
1058 		    !(dev->sc_flags & SFAS_ACTIVE))
1059 			*rp->sfas_command = SFAS_CMD_ENABLE_RESEL;
1060 
1061 		splx(s);
1062 
1063 		/* Select the first pre-initialized nexus we find. */
1064 		for(i=0; i<8; i++)
1065 			if (dev->sc_nexus[i].flags & (SFAS_NF_SELECT_ME | SFAS_NF_RETRY_SELECT))
1066 				if (sfas_select_unit(dev, i) == 2)
1067 					break;
1068 
1069 		/* We are done with this nexus! */
1070 		if (nexus->state == SFAS_NS_FINISHED)
1071 			sfas_scsidone(dev, nexus->xs, nexus->status);
1072 
1073 		return(1);
1074 	}
1075 
1076 	switch(nexus->state) {
1077 	case SFAS_NS_SELECTED:
1078 		dev->sc_cur_nexus = nexus;
1079 		dev->sc_sel_nexus = 0;
1080 
1081 		nexus->flags &= ~SFAS_NF_SELECT_ME;
1082 
1083 		/*
1084 		 * We have selected a unit. Setup chip, restore pointers and
1085 		 * light the led.
1086 		 */
1087 		*rp->sfas_syncper = nexus->syncper;
1088 		*rp->sfas_syncoff = nexus->syncoff;
1089 		*rp->sfas_config3 = nexus->config3;
1090 
1091 		sfas_restore_pointers(dev);
1092 
1093 		nexus->status	= 0xFF;
1094 		dev->sc_msg_in[0] = 0xFF;
1095 		dev->sc_msg_in_len= 0;
1096 
1097 		dev->sc_led(dev, 1);
1098 
1099 		break;
1100 
1101 	case SFAS_NS_DATA_IN:
1102 	case SFAS_NS_DATA_OUT:
1103 		/* We have transfered data. */
1104 		if (dev->sc_dma_len)
1105 			if (dev->sc_cur_link < dev->sc_max_link) {
1106 				/*
1107 				 * Clean up DMA and at the same time get how
1108 				 * many bytes that were NOT transfered.
1109 				 */
1110 			  left = dev->sc_setup_dma(dev, 0, 0, SFAS_DMA_CLEAR);
1111 			  len  = dev->sc_dma_len;
1112 
1113 			  if (nexus->state == SFAS_NS_DATA_IN) {
1114 			    /*
1115 			     * If we were bumping we may have had an odd length
1116 			     * which means that there may be bytes left in the
1117 			     * fifo. We also need to move the data from the
1118 			     * bump buffer to the actual memory.
1119 			     */
1120 			    if (dev->sc_dma_buf == dev->sc_bump_pa)
1121 			    {
1122 			      while((*rp->sfas_fifo_flags&SFAS_FIFO_COUNT_MASK)
1123 				    && left)
1124 				dev->sc_bump_va[len-(left--)] = *rp->sfas_fifo;
1125 
1126 			      memcpy(dev->sc_buf, dev->sc_bump_va, len-left);
1127 			    }
1128 			  } else {
1129 			    /* Count any unsent bytes and flush them. */
1130 			    left+= *rp->sfas_fifo_flags & SFAS_FIFO_COUNT_MASK;
1131 			    *rp->sfas_command = SFAS_CMD_FLUSH_FIFO;
1132 			  }
1133 
1134 			  /*
1135 			   * Update pointers/length to reflect the transfered
1136 			   * data.
1137 			   */
1138 			  dev->sc_len -= len-left;
1139 			  dev->sc_buf += len-left;
1140 
1141 			  dev->sc_dma_buf = (char *)dev->sc_dma_buf + len-left;
1142 			  dev->sc_dma_len = left;
1143 
1144 			  dev->sc_dma_blk_ptr = (char *)dev->sc_dma_blk_ptr +
1145 				  len-left;
1146 			  dev->sc_dma_blk_len -= len-left;
1147 
1148 			  /*
1149 			   * If it was the end of a DMA block, we select the
1150 			   * next to begin with.
1151 			   */
1152 			  if (!dev->sc_dma_blk_len)
1153 			    dev->sc_cur_link++;
1154 			}
1155 		break;
1156 
1157 	case SFAS_NS_STATUS:
1158 		/*
1159 		 * If we were not sensing, grab the status byte. If we were
1160 		 * sensing and we got a bad status, let the user know.
1161 		 */
1162 
1163 		status = *rp->sfas_fifo;
1164 		msg = *rp->sfas_fifo;
1165 
1166 		nexus->status = status;
1167 		if (status != 0)
1168 			nexus->status = -1;
1169 
1170 		/*
1171 		 * Preload the command complete message. Handeled in
1172 		 * sfas_postaction.
1173 		 */
1174 		dev->sc_msg_in[0] = msg;
1175 		dev->sc_msg_in_len = 1;
1176 		nexus->flags |= SFAS_NF_HAS_MSG;
1177 		break;
1178 
1179 	default:
1180 		break;
1181 	}
1182 
1183 	return(0);
1184 }
1185 
1186 /*
1187  * Part three of the interrupt machine. Handle phase changes (and repeated
1188  * phase passes). We know that we have an active nexus here.
1189  */
1190 int
1191 sfas_postaction(struct sfas_softc *dev, sfas_regmap_p rp, struct nexus *nexus)
1192 {
1193 	int	i, len;
1194 	u_char	cmd;
1195 	short	offset, period;
1196 
1197 	cmd = 0;
1198 
1199 	switch(dev->sc_status & SFAS_STAT_PHASE_MASK) {
1200 	case SFAS_PHASE_DATA_OUT:
1201 	case SFAS_PHASE_DATA_IN:
1202 		if ((dev->sc_status & SFAS_STAT_PHASE_MASK) ==
1203 		    SFAS_PHASE_DATA_OUT)
1204 			nexus->state = SFAS_NS_DATA_OUT;
1205 		else
1206 			nexus->state = SFAS_NS_DATA_IN;
1207 
1208 		/* Make DMA ready to accept new data. Load active pointers
1209 		 * from the DMA block. */
1210 		dev->sc_setup_dma(dev, 0, 0, SFAS_DMA_CLEAR);
1211 		if (dev->sc_cur_link < dev->sc_max_link) {
1212 		  if (!dev->sc_dma_blk_len) {
1213 		    dev->sc_dma_blk_ptr = dev->sc_chain[dev->sc_cur_link].ptr;
1214 		    dev->sc_dma_blk_len = dev->sc_chain[dev->sc_cur_link].len;
1215 		    dev->sc_dma_blk_flg = dev->sc_chain[dev->sc_cur_link].flg;
1216 		  }
1217 
1218 		  /* We should use polled IO here. */
1219 		  if (dev->sc_dma_blk_flg == SFAS_CHAIN_PRG) {
1220 			dev->sc_ixfer(dev, nexus->xs->xs_control & XS_CTL_POLL);
1221 			dev->sc_cur_link++;
1222 			dev->sc_dma_len = 0;
1223 			break;
1224 		  }
1225 		  else if (dev->sc_dma_blk_flg == SFAS_CHAIN_BUMP)
1226 			len = dev->sc_dma_blk_len;
1227 		  else
1228 			len = dev->sc_need_bump(dev, dev->sc_dma_blk_ptr,
1229 						dev->sc_dma_blk_len);
1230 
1231 		  /*
1232 		   * If len != 0 we must bump the data, else we just DMA it
1233 		   * straight into memory.
1234 		   */
1235 		  if (len) {
1236 			dev->sc_dma_buf = dev->sc_bump_pa;
1237 			dev->sc_dma_len = len;
1238 
1239 			if (nexus->state == SFAS_NS_DATA_OUT)
1240 			  memcpy(dev->sc_bump_va, dev->sc_buf, dev->sc_dma_len);
1241 		  } else {
1242 			dev->sc_dma_buf = dev->sc_dma_blk_ptr;
1243 			dev->sc_dma_len = dev->sc_dma_blk_len;
1244 		  }
1245 
1246 		  /* Load DMA with address and length of transfer. */
1247 		  dev->sc_setup_dma(dev, dev->sc_dma_buf, dev->sc_dma_len,
1248 				    ((nexus->state == SFAS_NS_DATA_OUT) ?
1249 				     SFAS_DMA_WRITE : SFAS_DMA_READ));
1250 
1251 /*		  printf("Using DMA !!!!\n");*/
1252 		  cmd = SFAS_CMD_TRANSFER_INFO | SFAS_CMD_DMA;
1253 		} else {
1254 			/*
1255 			 * Hmmm, the unit wants more info than we have or has
1256 			 * more than we want. Let the chip handle that.
1257 			 */
1258 
1259 			*rp->sfas_tc_low = 0; /* was 256 but this does not make sense */
1260 			*rp->sfas_tc_mid = 1;
1261 			*rp->sfas_tc_high = 0;
1262 			cmd = SFAS_CMD_TRANSFER_PAD;
1263 		}
1264 		break;
1265 
1266 	case SFAS_PHASE_COMMAND:
1267 		/* The scsi unit wants the command, send it. */
1268 		nexus->state = SFAS_NS_SVC;
1269 
1270 		*rp->sfas_command = SFAS_CMD_FLUSH_FIFO;
1271 		for(i=0; i<5; i++);
1272 
1273 		for(i=0; i<nexus->clen; i++)
1274 			*rp->sfas_fifo = nexus->cbuf[i];
1275 		cmd = SFAS_CMD_TRANSFER_INFO;
1276 		break;
1277 
1278 	case SFAS_PHASE_STATUS:
1279 		/*
1280 		 * We've got status phase. Request status and command
1281 		 * complete message.
1282 		 */
1283 		nexus->state = SFAS_NS_STATUS;
1284 		cmd = SFAS_CMD_COMMAND_COMPLETE;
1285 		break;
1286 
1287 	case SFAS_PHASE_MESSAGE_OUT:
1288 		/*
1289 		 * Either the scsi unit wants us to send a message or we have
1290 		 * asked for it by seting the ATN bit.
1291 		 */
1292 		nexus->state = SFAS_NS_MSG_OUT;
1293 
1294 		*rp->sfas_command = SFAS_CMD_FLUSH_FIFO;
1295 
1296 		if (nexus->flags & SFAS_NF_DO_SDTR) {
1297 			/* Send a Synchronous Data Transfer Request. */
1298 
1299 			sfas_build_sdtrm(dev, nexus->period, nexus->offset);
1300 			nexus->flags |= SFAS_NF_SDTR_SENT;
1301 			nexus->flags &= ~SFAS_NF_DO_SDTR;
1302 		} else if (nexus->flags & SFAS_NF_RESET) {
1303 			/* Send a reset scsi unit message. */
1304 
1305 			dev->sc_msg_out[0] = 0x0C;
1306 			dev->sc_msg_out_len = 1;
1307 			nexus->state = SFAS_NS_RESET;
1308 			nexus->flags &= ~SFAS_NF_RESET;
1309 		} else if (dev->sc_msg_out_len == 0) {
1310 			/* Don't know what to send so we send a NOP message. */
1311 
1312 			dev->sc_msg_out[0] = 0x08;
1313 			dev->sc_msg_out_len = 1;
1314 		}
1315 
1316 		cmd = SFAS_CMD_TRANSFER_INFO;
1317 
1318 		for(i=0; i<dev->sc_msg_out_len; i++)
1319 			*rp->sfas_fifo = dev->sc_msg_out[i];
1320 		dev->sc_msg_out_len = 0;
1321 
1322 		break;
1323 
1324 	case SFAS_PHASE_MESSAGE_IN:
1325 		/* Receive a message from the scsi unit. */
1326 		nexus->state = SFAS_NS_MSG_IN;
1327 
1328 		while(!(nexus->flags & SFAS_NF_HAS_MSG)) {
1329 			*rp->sfas_command = SFAS_CMD_TRANSFER_INFO;
1330 			sfasiwait(dev);
1331 
1332 			dev->sc_msg_in[dev->sc_msg_in_len++] = *rp->sfas_fifo;
1333 
1334 			/* Check if we got all the bytes in the message. */
1335 			if (dev->sc_msg_in[0] >= 0x80)       ;
1336 			else if (dev->sc_msg_in[0] >= 0x30)  ;
1337 			else if (((dev->sc_msg_in[0] >= 0x20) &&
1338 				  (dev->sc_msg_in_len == 2)) ||
1339 				 ((dev->sc_msg_in[0] != 0x01) &&
1340 				  (dev->sc_msg_in_len == 1))) {
1341 				nexus->flags |= SFAS_NF_HAS_MSG;
1342 				break;
1343 			} else {
1344 			  if (dev->sc_msg_in_len >= 2)
1345 			    if ((dev->sc_msg_in[1]+2) == dev->sc_msg_in_len) {
1346 				nexus->flags |= SFAS_NF_HAS_MSG;
1347 				break;
1348 			    }
1349 			}
1350 
1351 			*rp->sfas_command = SFAS_CMD_MESSAGE_ACCEPTED;
1352 			sfasiwait(dev);
1353 
1354 			if ((dev->sc_status & SFAS_STAT_PHASE_MASK) !=
1355 			    SFAS_PHASE_MESSAGE_IN)
1356 				break;
1357 		}
1358 
1359 		cmd = SFAS_CMD_MESSAGE_ACCEPTED;
1360 		if (nexus->flags & SFAS_NF_HAS_MSG) {
1361 			/* We have a message. Decode it. */
1362 
1363 			switch(dev->sc_msg_in[0]) {
1364 			case 0x00:	/* COMMAND COMPLETE */
1365 				nexus->state = SFAS_NS_DONE;
1366 				break;
1367 			case 0x04:	/* DISCONNECT */
1368 				nexus->state = SFAS_NS_DISCONNECTING;
1369 				break;
1370 			case 0x02:	/* SAVE DATA POINTER */
1371 				sfas_save_pointers(dev);
1372 				break;
1373 			case 0x03:	/* RESTORE DATA POINTERS */
1374 				sfas_restore_pointers(dev);
1375 				break;
1376 			case 0x07:	/* MESSAGE REJECT */
1377 				/*
1378 				 * If we had sent a SDTR and we got a message
1379 				 * reject, the scsi docs say that we must go
1380 				 * to async transfer.
1381 				 */
1382 				if (nexus->flags & SFAS_NF_SDTR_SENT) {
1383 					nexus->flags &= ~SFAS_NF_SDTR_SENT;
1384 
1385 					nexus->config3 &= ~SFAS_CFG3_FASTSCSI;
1386 					nexus->syncper = 5;
1387 					nexus->syncoff = 0;
1388 
1389 					*rp->sfas_syncper = nexus->syncper;
1390 					*rp->sfas_syncoff = nexus->syncoff;
1391 					*rp->sfas_config3 = nexus->config3;
1392 				} else
1393 				/*
1394 				 * Something was rejected but we don't know
1395 				 * what! PANIC!
1396 				 */
1397 				  panic("sfasintr: Unknown message rejected!");
1398 				break;
1399 			case 0x08:	/* MO OPERATION */
1400 				break;
1401 			case 0x01:	/* EXTENDED MESSAGE */
1402 				switch(dev->sc_msg_in[2]) {
1403 				case 0x01:/* SYNC. DATA TRANSFER REQUEST */
1404 					/* Decode the SDTR message. */
1405 					period = 4*dev->sc_msg_in[3];
1406 					offset = dev->sc_msg_in[4];
1407 
1408 					/*
1409 					 * Make sure that the specs are within
1410 					 * chip limits. Note that if we
1411 					 * initiated the negotiation the specs
1412 					 * WILL be withing chip limits. If it
1413 					 * was the scsi unit that initiated
1414 					 * the negotiation, the specs may be
1415 					 * to high.
1416 					 */
1417 					if (offset > 16)
1418 						offset = 16;
1419 					if ((period < 200) &&
1420 					    (dev->sc_clock_freq <= 25))
1421 						period = 200;
1422 
1423 					if (offset == 0)
1424 					       period = 5*dev->sc_clock_period;
1425 
1426 					nexus->syncper = period/
1427 							  dev->sc_clock_period;
1428 					nexus->syncoff = offset;
1429 
1430 					if (period < 200)
1431 					  nexus->config3 |= SFAS_CFG3_FASTSCSI;
1432 					else
1433 					  nexus->config3 &=~SFAS_CFG3_FASTSCSI;
1434 
1435 					nexus->flags |= SFAS_NF_SYNC_TESTED;
1436 
1437 					*rp->sfas_syncper = nexus->syncper;
1438 					*rp->sfas_syncoff = nexus->syncoff;
1439 					*rp->sfas_config3 = nexus->config3;
1440 
1441 					/*
1442 					 * Hmmm, it seems that the scsi unit
1443 					 * initiated sync negotiation, so lets
1444 					 * reply acording to scsi-2 standard.
1445 					 */
1446 					if (!(nexus->flags& SFAS_NF_SDTR_SENT))
1447 					{
1448 					  if ((dev->sc_config_flags &
1449 					       SFAS_NO_SYNCH) ||
1450 					      (dev->sc_config_flags &
1451 					       SFAS_NO_DMA) ||
1452 					      sfas_inhibit_sync[
1453 							nexus->lun_unit & 7]) {
1454 					          period = 200;
1455 					          offset = 0;
1456 					  }
1457 
1458 					  nexus->offset = offset;
1459 					  nexus->period = period;
1460 					  nexus->flags |= SFAS_NF_DO_SDTR;
1461 					  *rp->sfas_command = SFAS_CMD_SET_ATN;
1462 					}
1463 
1464 					nexus->flags &= ~SFAS_NF_SDTR_SENT;
1465 					break;
1466 
1467 				case 0x00: /* MODIFY DATA POINTERS */
1468 				case 0x02: /* EXTENDED IDENTIFY (SCSI-1) */
1469 				case 0x03: /* WIDE DATA TRANSFER REQUEST */
1470 			        default:
1471 					/* Reject any unhandeled messages. */
1472 
1473 					dev->sc_msg_out[0] = 0x07;
1474 					dev->sc_msg_out_len = 1;
1475 					*rp->sfas_command = SFAS_CMD_SET_ATN;
1476 					cmd = SFAS_CMD_MESSAGE_ACCEPTED;
1477 					break;
1478 				}
1479 				break;
1480 
1481 			default:
1482 				/* Reject any unhandeled messages. */
1483 
1484 				dev->sc_msg_out[0] = 0x07;
1485 				dev->sc_msg_out_len = 1;
1486 				*rp->sfas_command = SFAS_CMD_SET_ATN;
1487 				cmd = SFAS_CMD_MESSAGE_ACCEPTED;
1488 				break;
1489 			}
1490 			nexus->flags &= ~SFAS_NF_HAS_MSG;
1491 			dev->sc_msg_in_len = 0;
1492 		}
1493 		break;
1494 	default:
1495 		printf("SFASINTR: UNKNOWN PHASE! phase: %d\n",
1496 		       dev->sc_status & SFAS_STAT_PHASE_MASK);
1497 		dev->sc_led(dev, 0);
1498 		sfas_scsidone(dev, nexus->xs, -4);
1499 
1500 		return(-1);
1501 	}
1502 
1503 	if (cmd)
1504 		*rp->sfas_command = cmd;
1505 
1506 	return(0);
1507 }
1508 
1509 /*
1510  * Stub for interrupt machine.
1511  */
1512 void
1513 sfasintr(struct sfas_softc *dev)
1514 {
1515 	sfas_regmap_p	 rp;
1516 	struct nexus	*nexus;
1517 
1518 	rp = dev->sc_fas;
1519 
1520 	if (!sfas_pretests(dev, rp)) {
1521 
1522 		nexus = dev->sc_cur_nexus;
1523 		if (nexus == NULL)
1524 			nexus = dev->sc_sel_nexus;
1525 
1526 		if (nexus)
1527 			if (!sfas_midaction(dev, rp, nexus))
1528 				sfas_postaction(dev, rp, nexus);
1529 	}
1530 }
1531 
1532 /*
1533  * sfasicmd is used to perform IO when we can't use interrupts. sfasicmd
1534  * emulates the normal environment by waiting for the chip and calling
1535  * sfasintr.
1536  */
1537 void
1538 sfasicmd(struct sfas_softc *dev, struct sfas_pending *pendp)
1539 {
1540 	sfas_regmap_p	 rp;
1541 	struct nexus	*nexus;
1542 
1543 	nexus = &dev->sc_nexus[pendp->xs->xs_periph->periph_target];
1544 	rp = dev->sc_fas;
1545 
1546 	if (!sfasselect(dev, pendp, (char *)pendp->xs->cmd, pendp->xs->cmdlen,
1547 			(char *)pendp->xs->data, pendp->xs->datalen,
1548 			SFAS_SELECT_I))
1549 		panic("sfasicmd: Couldn't select unit");
1550 
1551 	while(nexus->state != SFAS_NS_FINISHED) {
1552 		sfasiwait(dev);
1553 		sfasintr(dev);
1554 	}
1555 
1556 	nexus->flags &= ~SFAS_NF_SYNC_TESTED;
1557 }
1558 
1559 
1560 #ifdef SFAS_DEBUG
1561 
1562 void
1563 dump_nexus(struct nexus *nexus)
1564 {
1565 	int loop;
1566 
1567 	printf("nexus=%08x\n", (u_int)nexus);
1568 	printf("scsi_fer=%08x\n", (u_int)nexus->xs);
1569 	printf("ID=%02x\n", nexus->ID);
1570 	printf("clen=%02x\n", nexus->clen);
1571 	printf("cbuf=");
1572 	for (loop = 0; loop< 14; ++loop)
1573 		printf(" %02x\n", nexus->cbuf[loop]);
1574 	printf("\n");
1575 	printf("DMA:\n");
1576 	for (loop = 0; loop < MAXCHAIN; ++loop)
1577 		printf("dma_chain: %08x %04x %04x\n", nexus->dma[loop].ptr,
1578 		    nexus->dma[loop].len, nexus->dma[loop].flg);
1579 	printf("\n");
1580 
1581 	printf("max_link=%d\n", nexus->max_link);
1582 	printf("cur_link=%d\n", nexus->cur_link);
1583 
1584 	printf("buf=%08x\n", (u_int)nexus->buf);
1585 	printf("len=%08x\n", nexus->len);
1586 	printf("dma_buf=%08x\n", (u_int)nexus->dma_buf);
1587 	printf("dma_len=%08x\n", nexus->dma_len);
1588 	printf("dma_blk_ptr=%08x\n", (u_int)nexus->dma_blk_ptr);
1589 	printf("dma_blk_len=%08x\n", nexus->dma_blk_len);
1590 	printf("dma_blk_flag=%08x\n", nexus->dma_blk_flg);
1591 	printf("state=%02x\n", nexus->state);
1592 	printf("flags=%04x\n", nexus->flags);
1593 	printf("period=%d\n", nexus->period);
1594 	printf("offset=%d\n", nexus->offset);
1595 	printf("syncper=%d\n", nexus->syncper);
1596 	printf("syncoff=%d\n", nexus->syncoff);
1597 	printf("config3=%02x\n", nexus->config3);
1598 	printf("lun_unit=%d\n", nexus->lun_unit);
1599 	printf("status=%02x\n", nexus->status);
1600 	printf("\n");
1601 }
1602 
1603 void
1604 dump_nexii(struct sfas_softc *sc)
1605 {
1606 	int loop;
1607 
1608 	for (loop = 0; loop < 8; ++loop) {
1609 		dump_nexus(&sc->sc_nexus[loop]);
1610 	}
1611 }
1612 
1613 void
1614 dump_sfassoftc(struct sfas_softc *sc)
1615 {
1616 	printf("sfassoftc @ 0x%08x\n", (u_int)sc);
1617 	printf("clock_freq = %d\n", sc->sc_clock_freq);
1618 	printf("timeout = %d\n", sc->sc_timeout);
1619 	printf("host_id = %d\n", sc->sc_host_id);
1620 	printf("config_flags = 0x%08x\n", sc->sc_config_flags);
1621 	printf("led_status = %d\n", sc->sc_led_status);
1622 
1623 	dump_nexii(sc);
1624 	printf("cur_nexus = 0x%08x\n", (u_int)sc->sc_cur_nexus);
1625 	printf("sel_nexus = 0x%08x\n", (u_int)sc->sc_sel_nexus);
1626 	printf("\n");
1627 }
1628 
1629 #endif	/* SFAS_DEBUG */
1630