xref: /netbsd-src/sys/arch/acorn32/podulebus/sfas.c (revision 08c81a9c2dc8c7300e893321eb65c0925d60871c)
1 /*	$NetBSD: sfas.c,v 1.7 2002/08/22 01:13:54 thorpej Exp $	*/
2 
3 /*
4  * Copyright (c) 1995 Scott Stevens
5  * Copyright (c) 1995 Daniel Widenfalk
6  * Copyright (c) 1994 Christian E. Hopps
7  * Copyright (c) 1990 The Regents of the University of California.
8  * All rights reserved.
9  *
10  * This code is derived from software contributed to Berkeley by
11  * Van Jacobson of Lawrence Berkeley Laboratory.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. All advertising materials mentioning features or use of this software
22  *    must display the following acknowledgement:
23  *	This product includes software developed by the University of
24  *	California, Berkeley and its contributors.
25  * 4. Neither the name of the University nor the names of its contributors
26  *    may be used to endorse or promote products derived from this software
27  *    without specific prior written permission.
28  *
29  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39  * SUCH DAMAGE.
40  *
41  *	@(#)scsi.c	7.5 (Berkeley) 5/4/91
42  */
43 
44 /*
45  * Emulex FAS216 scsi adaptor driver
46  */
47 
48 /*
49  * Modified for NetBSD/arm32 by Scott Stevens
50  */
51 
52 #include <sys/param.h>
53 #include <sys/systm.h>
54 #include <sys/device.h>
55 #include <sys/buf.h>
56 #include <sys/proc.h>
57 
58 #include <dev/scsipi/scsi_all.h>
59 #include <dev/scsipi/scsipi_all.h>
60 #include <dev/scsipi/scsiconf.h>
61 
62 #include <uvm/uvm_extern.h>
63 
64 #include <machine/pmap.h>
65 #include <machine/cpu.h>
66 #include <machine/io.h>
67 #include <machine/intr.h>
68 #include <arm/arm32/katelib.h>
69 #include <acorn32/podulebus/podulebus.h>
70 #include <acorn32/podulebus/sfasreg.h>
71 #include <acorn32/podulebus/sfasvar.h>
72 
73 void sfasinitialize __P((struct sfas_softc *));
74 void sfas_minphys   __P((struct buf *bp));
75 void sfas_scsi_request __P((struct scsipi_channel *,
76 					scsipi_adapter_req_t, void *));
77 void sfas_donextcmd __P((struct sfas_softc *dev, struct sfas_pending *pendp));
78 void sfas_scsidone  __P((struct sfas_softc *dev, struct scsipi_xfer *xs,
79 			 int stat));
80 void sfasintr	    __P((struct sfas_softc *dev));
81 void sfasiwait	    __P((struct sfas_softc *dev));
82 void sfas_ixfer	    __P((struct sfas_softc *dev, int polling));
83 void sfasreset	    __P((struct sfas_softc *dev, int how));
84 int  sfasselect	    __P((struct sfas_softc *dev, struct sfas_pending *pendp,
85 			 unsigned char *cbuf, int clen,
86 			 unsigned char *buf, int len, int mode));
87 void sfasicmd	    __P((struct sfas_softc *dev, struct sfas_pending *pendp));
88 void sfasgo         __P((struct sfas_softc *dev, struct sfas_pending *pendp));
89 
90 /*
91  * Initialize these to make 'em patchable. Defaults to enable sync and discon.
92  */
93 u_char	sfas_inhibit_sync[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
94 u_char	sfas_inhibit_disc[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
95 
96 #define DEBUG
97 #ifdef DEBUG
98 #define QPRINTF(a) if (sfas_debug > 1) printf a
99 int	sfas_debug = 2;
100 #else
101 #define QPRINTF
102 #endif
103 
104 /*
105  * default minphys routine for sfas based controllers
106  */
107 void
108 sfas_minphys(bp)
109 	struct buf *bp;
110 {
111 
112 	/*
113 	 * No max transfer at this level.
114 	 */
115 	minphys(bp);
116 }
117 
118 /*
119  * Initialize the nexus structs.
120  */
121 void
122 sfas_init_nexus(dev, nexus)
123 	struct sfas_softc *dev;
124 	struct nexus	  *nexus;
125 {
126 	bzero(nexus, sizeof(struct nexus));
127 
128 	nexus->state	= SFAS_NS_IDLE;
129 	nexus->period	= 200;
130 	nexus->offset	= 0;
131 	nexus->syncper	= 5;
132 	nexus->syncoff	= 0;
133 	nexus->config3	= dev->sc_config3 & ~SFAS_CFG3_FASTSCSI;
134 }
135 
136 void
137 sfasinitialize(dev)
138 	struct sfas_softc *dev;
139 {
140 	u_int		*pte;
141 	int		 i;
142 
143 	dev->sc_led_status = 0;
144 
145 	TAILQ_INIT(&dev->sc_xs_pending);
146 	TAILQ_INIT(&dev->sc_xs_free);
147 
148 /*
149  * Initialize the sfas_pending structs and link them into the free list. We
150  * have to set vm_link_data.pages to 0 or the vm FIX won't work.
151  */
152 	for(i=0; i<MAXPENDING; i++) {
153 		TAILQ_INSERT_TAIL(&dev->sc_xs_free, &dev->sc_xs_store[i],
154 				  link);
155 	}
156 
157 /*
158  * Calculate the correct clock conversion factor 2 <= factor <= 8, i.e. set
159  * the factor to clock_freq / 5 (int).
160  */
161 	if (dev->sc_clock_freq <= 10)
162 		dev->sc_clock_conv_fact = 2;
163 	if (dev->sc_clock_freq <= 40)
164 		dev->sc_clock_conv_fact = 2+((dev->sc_clock_freq-10)/5);
165 	else
166 		panic("sfasinitialize: Clock frequence too high");
167 
168 /* Setup and save the basic configuration registers */
169 	dev->sc_config1 = (dev->sc_host_id & SFAS_CFG1_BUS_ID_MASK);
170 	dev->sc_config2 = SFAS_CFG2_FEATURES_ENABLE;
171 	dev->sc_config3 = (dev->sc_clock_freq > 25 ? SFAS_CFG3_FASTCLK : 0);
172 
173 /* Precalculate timeout value and clock period. */
174 /* Ekkk ... floating point in the kernel !!!! */
175 /*	dev->sc_timeout_val  = 1+dev->sc_timeout*dev->sc_clock_freq/
176 				 (7.682*dev->sc_clock_conv_fact);*/
177 	dev->sc_timeout_val  = 1+dev->sc_timeout*dev->sc_clock_freq/
178 				 ((7682*dev->sc_clock_conv_fact)/1000);
179 	dev->sc_clock_period = 1000/dev->sc_clock_freq;
180 
181 	sfasreset(dev, 1 | 2);	/* Reset Chip and Bus */
182 
183 	dev->sc_units_disconnected = 0;
184 	dev->sc_msg_in_len = 0;
185 	dev->sc_msg_out_len = 0;
186 
187 	dev->sc_flags = 0;
188 
189 	for(i=0; i<8; i++)
190 		sfas_init_nexus(dev, &dev->sc_nexus[i]);
191 
192 	if (dev->sc_ixfer == NULL)
193 		dev->sc_ixfer = sfas_ixfer;
194 
195 /*
196  * Setup bump buffer.
197  */
198 	dev->sc_bump_va = (u_char *)uvm_km_zalloc(kernel_map, dev->sc_bump_sz);
199 	(void) pmap_extract(pmap_kernel(), (vaddr_t)dev->sc_bump_va,
200 	    (paddr_t *)&dev->sc_bump_pa);
201 
202 /*
203  * Setup pages to noncachable, that way we don't have to flush the cache
204  * every time we need "bumped" transfer.
205  */
206 	pte = vtopte((vaddr_t) dev->sc_bump_va);
207 	*pte &= ~(L2_C | L2_B);
208 	PTE_SYNC(pte);
209 	cpu_tlb_flushD();
210 	cpu_dcache_wbinv_range((vm_offset_t)dev->sc_bump_va, NBPG);
211 
212 	printf(" dmabuf V0x%08x P0x%08x", (u_int)dev->sc_bump_va, (u_int)dev->sc_bump_pa);
213 }
214 
215 
216 /*
217  * used by specific sfas controller
218  */
219 void
220 sfas_scsi_request(struct scsipi_channel *chan, scsipi_adapter_req_t req,
221 								void *arg)
222 {
223 	struct scsipi_xfer *xs;
224 	struct sfas_softc	*dev = (void *)chan->chan_adapter->adapt_dev;
225 	struct scsipi_periph	*periph;
226 	struct sfas_pending	*pendp;
227 	int			 flags, s, target;
228 
229 	switch (req) {
230 	case ADAPTER_REQ_RUN_XFER:
231 		xs = arg;
232 		periph = xs->xs_periph;
233 		flags = xs->xs_control;
234 		target = periph->periph_target;
235 
236 		if (flags & XS_CTL_DATA_UIO)
237 			panic("sfas: scsi data uio requested");
238 
239 		if ((flags & XS_CTL_POLL) && (dev->sc_flags & SFAS_ACTIVE))
240 			panic("sfas_scsicmd: busy");
241 
242 /* Get hold of a sfas_pending block. */
243 		s = splbio();
244 		pendp = dev->sc_xs_free.tqh_first;
245 		if (pendp == NULL) {
246 			xs->error = XS_RESOURCE_SHORTAGE;
247 			scsipi_done(xs);
248 			splx(s);
249 			return;
250 		}
251 		TAILQ_REMOVE(&dev->sc_xs_free, pendp, link);
252 		pendp->xs = xs;
253 		splx(s);
254 
255 
256 /* If the chip if busy OR the unit is busy, we have to wait for out turn. */
257 		if ((dev->sc_flags & SFAS_ACTIVE) ||
258 		    (dev->sc_nexus[target].flags & SFAS_NF_UNIT_BUSY)) {
259 			s = splbio();
260 			TAILQ_INSERT_TAIL(&dev->sc_xs_pending, pendp, link);
261 			splx(s);
262 		} else
263 			sfas_donextcmd(dev, pendp);
264 
265 		return;
266 
267 	case ADAPTER_REQ_GROW_RESOURCES:
268 	case ADAPTER_REQ_SET_XFER_MODE:
269 		/* XXX Not supported. */
270 		return;
271 	}
272 }
273 
274 /*
275  * Actually select the unit, whereby the whole scsi-process is started.
276  */
277 void
278 sfas_donextcmd(dev, pendp)
279 	struct sfas_softc	*dev;
280 	struct sfas_pending	*pendp;
281 {
282 	int	s;
283 
284 /*
285  * Special case for scsi unit reset. I think this is waterproof. We first
286  * select the unit during splbio. We then cycle through the generated
287  * interrupts until the interrupt routine signals that the unit has
288  * acknowledged the reset. After that we have to wait a reset to select
289  * delay before anything else can happend.
290  */
291 	if (pendp->xs->xs_control & XS_CTL_RESET) {
292 		struct nexus	*nexus;
293 
294 		s = splbio();
295 		while(!sfasselect(dev, pendp, 0, 0, 0, 0, SFAS_SELECT_K)) {
296 			splx(s);
297 			delay(10);
298 			s = splbio();
299 		}
300 
301 		nexus = dev->sc_cur_nexus;
302 		while(nexus->flags & SFAS_NF_UNIT_BUSY) {
303 			sfasiwait(dev);
304 			sfasintr(dev);
305 		}
306 
307 		nexus->flags |= SFAS_NF_UNIT_BUSY;
308 		splx(s);
309 
310 		sfasreset(dev, 0);
311 
312 		s = splbio();
313 		nexus->flags &= ~SFAS_NF_UNIT_BUSY;
314 		splx(s);
315 	}
316 
317 /*
318  * If we are polling, go to splbio and perform the command, else we poke
319  * the scsi-bus via sfasgo to get the interrupt machine going.
320  */
321 	if (pendp->xs->xs_control & XS_CTL_POLL) {
322 		s = splbio();
323 		sfasicmd(dev, pendp);
324 		TAILQ_INSERT_TAIL(&dev->sc_xs_free, pendp, link);
325 		splx(s);
326 	} else {
327 		sfasgo(dev, pendp);
328 	}
329 }
330 
331 void
332 sfas_scsidone(dev, xs, stat)
333 	struct sfas_softc *dev;
334 	struct scsipi_xfer *xs;
335 	int		 stat;
336 {
337 	struct sfas_pending	*pendp;
338 	int			 s;
339 
340 	xs->status = stat;
341 
342 	if (stat == 0)
343 		xs->resid = 0;
344 	else {
345 		switch(stat) {
346 		case SCSI_CHECK:
347 		case SCSI_BUSY:
348 			xs->error = XS_BUSY;
349 			break;
350 		case -1:
351 			xs->error = XS_DRIVER_STUFFUP;
352 			QPRINTF(("sfas_scsicmd() bad %x\n", stat));
353 			break;
354 		default:
355 			xs->error = XS_TIMEOUT;
356 			break;
357 		}
358 	}
359 
360 /* Steal the next command from the queue so that one unit can't hog the bus. */
361 	s = splbio();
362 	pendp = dev->sc_xs_pending.tqh_first;
363 	while(pendp) {
364 		if (!(dev->sc_nexus[pendp->xs->xs_periph->periph_target].flags &
365 		      SFAS_NF_UNIT_BUSY))
366 			break;
367 		pendp = pendp->link.tqe_next;
368 	}
369 
370 	if (pendp != NULL) {
371 		TAILQ_REMOVE(&dev->sc_xs_pending, pendp, link);
372 	}
373 
374 	splx(s);
375 	scsipi_done(xs);
376 
377 	if (pendp)
378 		sfas_donextcmd(dev, pendp);
379 }
380 
381 /*
382  * There are two kinds of reset:
383  *  1) CHIP-bus reset. This also implies a SCSI-bus reset.
384  *  2) SCSI-bus reset.
385  * After the appropriate resets have been performed we wait a reset to select
386  * delay time.
387  */
388 void
389 sfasreset(dev, how)
390 	struct sfas_softc *dev;
391 	int		 how;
392 {
393 	sfas_regmap_p	rp;
394 	int		i, s;
395 
396 	rp = dev->sc_fas;
397 
398 	if (how & 1) {
399 		for(i=0; i<8; i++)
400 			sfas_init_nexus(dev, &dev->sc_nexus[i]);
401 
402 		*rp->sfas_command = SFAS_CMD_RESET_CHIP;
403 		delay(1);
404 		*rp->sfas_command = SFAS_CMD_NOP;
405 
406 		*rp->sfas_config1 = dev->sc_config1;
407 		*rp->sfas_config2 = dev->sc_config2;
408 		*rp->sfas_config3 = dev->sc_config3;
409 		*rp->sfas_timeout = dev->sc_timeout_val;
410 		*rp->sfas_clkconv = dev->sc_clock_conv_fact &
411 					SFAS_CLOCK_CONVERSION_MASK;
412 	}
413 
414 	if (how & 2) {
415 		for(i=0; i<8; i++)
416 			sfas_init_nexus(dev, &dev->sc_nexus[i]);
417 
418 		s = splbio();
419 
420 		*rp->sfas_command = SFAS_CMD_RESET_SCSI_BUS;
421 		delay(100);
422 
423 /* Skip interrupt generated by RESET_SCSI_BUS */
424 		while(*rp->sfas_status & SFAS_STAT_INTERRUPT_PENDING) {
425 			dev->sc_status = *rp->sfas_status;
426 			dev->sc_interrupt = *rp->sfas_interrupt;
427 
428 			delay(100);
429 		}
430 
431 		dev->sc_status = *rp->sfas_status;
432 		dev->sc_interrupt = *rp->sfas_interrupt;
433 
434 		splx(s);
435 	}
436 
437 	if (dev->sc_config_flags & SFAS_SLOW_START)
438 		delay(4*250000); /* RESET to SELECT DELAY*4 for slow devices */
439 	else
440 		delay(250000);	 /* RESET to SELECT DELAY */
441 }
442 
443 /*
444  * Save active data pointers to the nexus block currently active.
445  */
446 void
447 sfas_save_pointers(dev)
448 	struct sfas_softc *dev;
449 {
450 	struct nexus	*nx;
451 
452 	nx = dev->sc_cur_nexus;
453 	if (nx) {
454 		nx->cur_link	= dev->sc_cur_link;
455 		nx->max_link	= dev->sc_max_link;
456 		nx->buf		= dev->sc_buf;
457 		nx->len		= dev->sc_len;
458 		nx->dma_len	= dev->sc_dma_len;
459 		nx->dma_buf	= dev->sc_dma_buf;
460 		nx->dma_blk_flg	= dev->sc_dma_blk_flg;
461 		nx->dma_blk_len	= dev->sc_dma_blk_len;
462 		nx->dma_blk_ptr	= dev->sc_dma_blk_ptr;
463 	}
464 }
465 
466 /*
467  * Restore data pointers from the currently active nexus block.
468  */
469 void
470 sfas_restore_pointers(dev)
471 	struct sfas_softc *dev;
472 {
473 	struct nexus	*nx;
474 
475 	nx = dev->sc_cur_nexus;
476 	if (nx) {
477 		dev->sc_cur_link    = nx->cur_link;
478 		dev->sc_max_link    = nx->max_link;
479 		dev->sc_buf	    = nx->buf;
480 		dev->sc_len	    = nx->len;
481 		dev->sc_dma_len	    = nx->dma_len;
482 		dev->sc_dma_buf	    = nx->dma_buf;
483 		dev->sc_dma_blk_flg = nx->dma_blk_flg;
484 		dev->sc_dma_blk_len = nx->dma_blk_len;
485 		dev->sc_dma_blk_ptr = nx->dma_blk_ptr;
486 		dev->sc_chain	    = nx->dma;
487 		dev->sc_unit	    = (nx->lun_unit & 0x0F);
488 		dev->sc_lun	    = (nx->lun_unit & 0xF0) >> 4;
489 	}
490 }
491 
492 /*
493  * sfasiwait is used during interrupt and polled IO to wait for an event from
494  * the FAS chip. This function MUST NOT BE CALLED without interrupt disabled.
495  */
496 void
497 sfasiwait(dev)
498 	struct sfas_softc *dev;
499 {
500 	sfas_regmap_p	rp;
501 
502 /*
503  * If SFAS_DONT_WAIT is set, we have already grabbed the interrupt info
504  * elsewhere. So we don't have to wait for it.
505  */
506 	if (dev->sc_flags & SFAS_DONT_WAIT) {
507 		dev->sc_flags &= ~SFAS_DONT_WAIT;
508 		return;
509 	}
510 
511 	rp = dev->sc_fas;
512 
513 /* Wait for FAS chip to signal an interrupt. */
514 	while(!(*rp->sfas_status & SFAS_STAT_INTERRUPT_PENDING))
515 		delay(1);
516 
517 /* Grab interrupt info from chip. */
518 	dev->sc_status = *rp->sfas_status;
519 	dev->sc_interrupt = *rp->sfas_interrupt;
520 	if (dev->sc_interrupt & SFAS_INT_RESELECTED) {
521 		dev->sc_resel[0] = *rp->sfas_fifo;
522 		dev->sc_resel[1] = *rp->sfas_fifo;
523 	}
524 }
525 
526 /*
527  * Transfer info to/from device. sfas_ixfer uses polled IO+sfasiwait so the
528  * rules that apply to sfasiwait also applies here.
529  */
530 void
531 sfas_ixfer(dev, polling)
532 	struct sfas_softc *dev;
533 	int polling;
534 {
535 	sfas_regmap_p	 rp;
536 	u_char		*buf;
537 	int		 len, mode, phase;
538 
539 	rp = dev->sc_fas;
540 	buf = dev->sc_buf;
541 	len = dev->sc_len;
542 
543 /*
544  * Decode the scsi phase to determine whether we are reading or writing.
545  * mode == 1 => READ, mode == 0 => WRITE
546  */
547 	phase = dev->sc_status & SFAS_STAT_PHASE_MASK;
548 	mode = (phase == SFAS_PHASE_DATA_IN);
549 
550 	while(len && ((dev->sc_status & SFAS_STAT_PHASE_MASK) == phase))
551 		if (mode) {
552 			*rp->sfas_command = SFAS_CMD_TRANSFER_INFO;
553 
554 			sfasiwait(dev);
555 
556 			*buf++ = *rp->sfas_fifo;
557 			len--;
558 		} else {
559 			len--;
560 			*rp->sfas_fifo = *buf++;
561 			*rp->sfas_command = SFAS_CMD_TRANSFER_INFO;
562 
563 			sfasiwait(dev);
564 		}
565 
566 /* Update buffer pointers to reflect the sent/received data. */
567 	dev->sc_buf = buf;
568 	dev->sc_len = len;
569 
570 /*
571  * Since the last sfasiwait will be a phase-change, we can't wait for it
572  * again later, so we have to signal that.
573  * Since this may be called from an interrupt initiated routine then we
574  * must call sfasintr again to avoid losing an interrupt. Phew!
575  */
576 	if(polling)
577 		dev->sc_flags |= SFAS_DONT_WAIT;
578 	else
579 		sfasintr(dev);
580 }
581 
582 /*
583  * Build a Synchronous Data Transfer Request message
584  */
585 void
586 sfas_build_sdtrm(dev, period, offset)
587 	struct sfas_softc *dev;
588 	int		  period;
589 	int		  offset;
590 {
591 	dev->sc_msg_out[0] = 0x01;
592 	dev->sc_msg_out[1] = 0x03;
593 	dev->sc_msg_out[2] = 0x01;
594 	dev->sc_msg_out[3] = period/4;
595 	dev->sc_msg_out[4] = offset;
596 	dev->sc_msg_out_len= 5;
597 }
598 
599 /*
600  * Arbitate the scsi bus and select the unit
601  */
602 int
603 sfas_select_unit(dev, target)
604 	struct sfas_softc *dev;
605 	short		  target;
606 {
607 	sfas_regmap_p	 rp;
608 	struct nexus	*nexus;
609 	int		 s, retcode, i;
610 	u_char		 cmd;
611 
612 	s = splbio();	/* Do this at splbio so that we won't be disturbed. */
613 
614 	retcode = 0;
615 
616 	nexus = &dev->sc_nexus[target];
617 
618 /*
619  * Check if the chip is busy. If not the we mark it as so and hope that nobody
620  * reselects us until we have grabbed the bus.
621  */
622 	if (!(dev->sc_flags & SFAS_ACTIVE) && !dev->sc_sel_nexus) {
623 		dev->sc_flags |= SFAS_ACTIVE;
624 
625 		rp = dev->sc_fas;
626 
627 		*rp->sfas_syncper = nexus->syncper;
628 		*rp->sfas_syncoff = nexus->syncoff;
629 		*rp->sfas_config3 = nexus->config3;
630 
631 		*rp->sfas_config1 = dev->sc_config1;
632 		*rp->sfas_timeout = dev->sc_timeout_val;
633 		*rp->sfas_dest_id = target;
634 
635 /* If nobody has stolen the bus, we can send a select command to the chip. */
636 		if (!(*rp->sfas_status & SFAS_STAT_INTERRUPT_PENDING)) {
637 			*rp->sfas_fifo = nexus->ID;
638 			if ((nexus->flags & (SFAS_NF_DO_SDTR | SFAS_NF_RESET))
639 			    || (dev->sc_msg_out_len != 0))
640 				cmd = SFAS_CMD_SEL_ATN_STOP;
641 			else {
642 				for(i=0; i<nexus->clen; i++)
643 					*rp->sfas_fifo = nexus->cbuf[i];
644 
645 				cmd = SFAS_CMD_SEL_ATN;
646 			}
647 
648 			dev->sc_sel_nexus = nexus;
649 
650 			*rp->sfas_command = cmd;
651 			retcode = 1;
652 			nexus->flags &= ~SFAS_NF_RETRY_SELECT;
653 		} else
654 			nexus->flags |= SFAS_NF_RETRY_SELECT;
655 	} else
656 		nexus->flags |= SFAS_NF_RETRY_SELECT;
657 
658 	splx(s);
659 	return(retcode);
660 }
661 
662 /*
663  * Grab the nexus if available else return 0.
664  */
665 struct nexus *
666 sfas_arbitate_target(dev, target)
667 	struct sfas_softc *dev;
668 	int		  target;
669 {
670 	struct nexus	*nexus;
671 	int		 s;
672 
673 /*
674  * This is realy simple. Raise interrupt level to splbio. Grab the nexus and
675  * leave.
676  */
677 	nexus = &dev->sc_nexus[target];
678 
679 	s = splbio();
680 
681 	if (nexus->flags & SFAS_NF_UNIT_BUSY)
682 		nexus = 0;
683 	else
684 		nexus->flags |= SFAS_NF_UNIT_BUSY;
685 
686 	splx(s);
687 	return(nexus);
688 }
689 
690 /*
691  * Setup a nexus for use. Initializes command, buffer pointers and dma chain.
692  */
693 void
694 sfas_setup_nexus(dev, nexus, pendp, cbuf, clen, buf, len, mode)
695 	struct sfas_softc	*dev;
696 	struct nexus		*nexus;
697 	struct sfas_pending	*pendp;
698 	unsigned char		*cbuf;
699 	int			 clen;
700 	unsigned char		*buf;
701 	int			 len;
702 	int			 mode;
703 {
704 	char	sync, target, lun;
705 
706 	target = pendp->xs->xs_periph->periph_target;
707 	lun    = pendp->xs->xs_periph->periph_lun;
708 
709 /*
710  * Adopt mode to reflect the config flags.
711  * If we can't use DMA we can't use synch transfer. Also check the
712  * sfas_inhibit_xxx[target] flags.
713  */
714 	if ((dev->sc_config_flags & (SFAS_NO_SYNCH | SFAS_NO_DMA)) ||
715 	    sfas_inhibit_sync[(int)target])
716 		mode &= ~SFAS_SELECT_S;
717 
718 	if ((dev->sc_config_flags & SFAS_NO_RESELECT) ||
719 	    sfas_inhibit_disc[(int)target])
720 		mode &= ~SFAS_SELECT_R;
721 
722 	nexus->xs		= pendp->xs;
723 
724 /* Setup the nexus struct. */
725 	nexus->ID	   = ((mode & SFAS_SELECT_R) ? 0xC0 : 0x80) | lun;
726 	nexus->clen	   = clen;
727 	bcopy(cbuf, nexus->cbuf, nexus->clen);
728 	nexus->cbuf[1] |= lun << 5;		/* Fix the lun bits */
729 	nexus->cur_link	   = 0;
730 	nexus->dma_len	   = 0;
731 	nexus->dma_buf	   = 0;
732 	nexus->dma_blk_len = 0;
733 	nexus->dma_blk_ptr = 0;
734 	nexus->len	   = len;
735 	nexus->buf	   = buf;
736 	nexus->lun_unit	   = (lun << 4) | target;
737 	nexus->state	   = SFAS_NS_SELECTED;
738 
739 /* We must keep these flags. All else must be zero. */
740 	nexus->flags	  &= SFAS_NF_UNIT_BUSY
741 			   | SFAS_NF_SYNC_TESTED | SFAS_NF_SELECT_ME;
742 
743 	if (mode & SFAS_SELECT_I)
744 		nexus->flags |= SFAS_NF_IMMEDIATE;
745 	if (mode & SFAS_SELECT_K)
746 		nexus->flags |= SFAS_NF_RESET;
747 
748 	sync  = ((mode & SFAS_SELECT_S) ? 1 : 0);
749 
750 /* We can't use sync during polled IO. */
751 	if (sync && (mode & SFAS_SELECT_I))
752 		sync = 0;
753 
754 	if (!sync &&
755 	    ((nexus->flags & SFAS_NF_SYNC_TESTED) && (nexus->offset != 0))) {
756 		/*
757 		 * If the scsi unit is set to synch transfer and we don't want
758 		 * that, we have to renegotiate.
759 		 */
760 
761 		nexus->flags |= SFAS_NF_DO_SDTR;
762 		nexus->period = 200;
763 		nexus->offset = 0;
764 	} else if (sync && !(nexus->flags & SFAS_NF_SYNC_TESTED)) {
765 		/*
766 		 * If the scsi unit is not set to synch transfer and we want
767 		 * that, we have to negotiate. This should realy base the
768 		 * period on the clock frequence rather than just check if
769 		 * >25Mhz
770 		 */
771 
772 		nexus->flags |= SFAS_NF_DO_SDTR;
773 		nexus->period = ((dev->sc_clock_freq>25) ? 100 : 200);
774 		nexus->offset = 8;
775 
776 		/* If the user has a long cable, we want to limit the period */
777 		if ((nexus->period == 100) &&
778 		    (dev->sc_config_flags & SFAS_SLOW_CABLE))
779 			nexus->period = 200;
780 	}
781 
782 /*
783  * Fake a dma-block for polled IO. This way we can use the same code to handle
784  * reselection. Much nicer this way.
785  */
786 	if ((mode & SFAS_SELECT_I) || (dev->sc_config_flags & SFAS_NO_DMA)) {
787 		nexus->dma[0].ptr = (vm_offset_t)buf;
788 		nexus->dma[0].len = len;
789 		nexus->dma[0].flg = SFAS_CHAIN_PRG;
790 		nexus->max_link   = 1;
791 	} else {
792 		nexus->max_link = dev->sc_build_dma_chain(dev, nexus->dma,
793 							  buf, len);
794 	}
795 
796 /* Flush the caches. */
797 
798 	if (len && !(mode & SFAS_SELECT_I))
799 		cpu_dcache_wbinv_range((vm_offset_t)buf, len);
800 }
801 
802 int
803 sfasselect(dev, pendp, cbuf, clen, buf, len, mode)
804 	struct sfas_softc	*dev;
805 	struct sfas_pending	*pendp;
806 	unsigned char		*cbuf;
807 	int			 clen;
808 	unsigned char		*buf;
809 	int			 len;
810 	int			 mode;
811 {
812 	struct nexus	*nexus;
813 
814 /* Get the nexus struct. */
815 	nexus = sfas_arbitate_target(dev, pendp->xs->xs_periph->periph_target);
816 	if (nexus == NULL)
817 		return(0);
818 
819 /* Setup the nexus struct. */
820 	sfas_setup_nexus(dev, nexus, pendp, cbuf, clen, buf, len, mode);
821 
822 /* Post it to the interrupt machine. */
823 	sfas_select_unit(dev, pendp->xs->xs_periph->periph_target);
824 
825 	return(1);
826 }
827 
828 void
829 sfasgo(dev, pendp)
830 	struct sfas_softc   *dev;
831 	struct sfas_pending *pendp;
832 {
833 	int	 s;
834 	char	*buf;
835 
836 	buf    = pendp->xs->data;
837 
838 	if (sfasselect(dev, pendp, (char *)pendp->xs->cmd, pendp->xs->cmdlen,
839 		      buf, pendp->xs->datalen, SFAS_SELECT_RS)) {
840 		/*
841 		 * We got the command going so the sfas_pending struct is now
842 		 * free to reuse.
843 		 */
844 
845 		s = splbio();
846 		TAILQ_INSERT_TAIL(&dev->sc_xs_free, pendp, link);
847 		splx(s);
848 	} else {
849 		/*
850 		 * We couldn't make the command fly so we have to wait. The
851 		 * struct MUST be inserted at the head to keep the order of
852 		 * the commands.
853 		 */
854 
855 		s = splbio();
856 		TAILQ_INSERT_HEAD(&dev->sc_xs_pending, pendp, link);
857 		splx(s);
858 	}
859 
860 	return;
861 }
862 
863 /*
864  * Part one of the interrupt machine. Error checks and reselection test.
865  * We don't know if we have an active nexus here!
866  */
867 int
868 sfas_pretests(dev, rp)
869 	struct sfas_softc *dev;
870 	sfas_regmap_p	  rp;
871 {
872 	struct nexus	*nexus;
873 	int		 i, s;
874 
875 	if (dev->sc_interrupt & SFAS_INT_SCSI_RESET_DETECTED) {
876 		/*
877 		 * Cleanup and notify user. Lets hope that this is all we
878 		 * have to do
879 		 */
880 
881 		for(i=0; i<8; i++) {
882 			if (dev->sc_nexus[i].xs)
883 				sfas_scsidone(dev, dev->sc_nexus[i].xs, -2);
884 
885 			sfas_init_nexus(dev, &dev->sc_nexus[i]);
886 		}
887 		printf("sfasintr: SCSI-RESET detected!");
888 		return(-1);
889 	}
890 
891 	if (dev->sc_interrupt & SFAS_INT_ILLEGAL_COMMAND) {
892 		/* Something went terrible wrong! Dump some data and panic! */
893 
894 		printf("FIFO:");
895 		while(*rp->sfas_fifo_flags & SFAS_FIFO_COUNT_MASK)
896 			printf(" %x", *rp->sfas_fifo);
897 		printf("\n");
898 
899 		printf("CMD: %x\n", *rp->sfas_command);
900 		panic("sfasintr: ILLEGAL COMMAND!");
901 	}
902 
903 	if (dev->sc_interrupt & SFAS_INT_RESELECTED) {
904 		/* We were reselected. Set the chip as busy */
905 
906 		s = splbio();
907 		dev->sc_flags |= SFAS_ACTIVE;
908 		if (dev->sc_sel_nexus) {
909 			dev->sc_sel_nexus->flags |= SFAS_NF_SELECT_ME;
910 			dev->sc_sel_nexus = 0;
911 		}
912 		splx(s);
913 
914 		if (dev->sc_units_disconnected) {
915 			/* Find out who reselected us. */
916 
917 			dev->sc_resel[0] &= ~(1<<dev->sc_host_id);
918 
919 			for(i=0; i<8; i++)
920 				if (dev->sc_resel[0] & (1<<i))
921 					break;
922 
923 			if (i == 8)
924 				panic("Illegal reselection!");
925 
926 			if (dev->sc_nexus[i].state == SFAS_NS_DISCONNECTED) {
927 				/*
928 				 * This unit had disconnected, so we reconnect
929 				 * it.
930 				 */
931 
932 				dev->sc_cur_nexus = &dev->sc_nexus[i];
933 				nexus = dev->sc_cur_nexus;
934 
935 				*rp->sfas_syncper = nexus->syncper;
936 				*rp->sfas_syncoff = nexus->syncoff;
937 				*rp->sfas_config3 = nexus->config3;
938 
939 				*rp->sfas_dest_id = i & 7;
940 
941 				dev->sc_units_disconnected--;
942 				dev->sc_msg_in_len= 0;
943 
944 				/* Restore active pointers. */
945 				sfas_restore_pointers(dev);
946 
947 				nexus->state = SFAS_NS_RESELECTED;
948 
949 				*rp->sfas_command = SFAS_CMD_MESSAGE_ACCEPTED;
950 
951 				return(1);
952 			}
953 		}
954 
955 		/* Somehow we got an illegal reselection. Dump and panic. */
956 		printf("sfasintr: resel[0] %x resel[1] %x disconnected %d\n",
957 		       dev->sc_resel[0], dev->sc_resel[1],
958 		       dev->sc_units_disconnected);
959 		panic("sfasintr: Unexpected reselection!");
960 	}
961 
962 	return(0);
963 }
964 
965 /*
966  * Part two of the interrupt machine. Handle disconnection and post command
967  * processing. We know that we have an active nexus here.
968  */
969 int
970 sfas_midaction(dev, rp, nexus)
971 	struct sfas_softc *dev;
972 	sfas_regmap_p	  rp;
973 	struct nexus	 *nexus;
974 {
975 	int	i, left, len, s;
976 	u_char	status, msg;
977 
978 	if (dev->sc_interrupt & SFAS_INT_DISCONNECT) {
979 		s = splbio();
980 		dev->sc_cur_nexus = 0;
981 
982 		/* Mark chip as busy and clean up the chip FIFO. */
983 		dev->sc_flags &= ~SFAS_ACTIVE;
984 		*rp->sfas_command = SFAS_CMD_FLUSH_FIFO;
985 
986 		/* Let the nexus state reflect what we have to do. */
987 		switch(nexus->state) {
988 		case SFAS_NS_SELECTED:
989 			dev->sc_sel_nexus = 0;
990 			nexus->flags &= ~SFAS_NF_SELECT_ME;
991 
992 			/*
993 			 * We were trying to select the unit. Probably no unit
994 			 * at this ID.
995 			 */
996 			nexus->xs->resid = dev->sc_len;
997 
998 			nexus->status = -2;
999 			nexus->flags &= ~SFAS_NF_UNIT_BUSY;
1000 			nexus->state = SFAS_NS_FINISHED;
1001 			break;
1002 
1003 		case SFAS_NS_DONE:
1004 			/* All done. */
1005 			nexus->xs->resid = dev->sc_len;
1006 
1007 			nexus->flags &= ~SFAS_NF_UNIT_BUSY;
1008 			nexus->state  = SFAS_NS_FINISHED;
1009 			dev->sc_led(dev, 0);
1010 			break;
1011 
1012 		case SFAS_NS_DISCONNECTING:
1013 			/*
1014 			 * We have received a DISCONNECT message, so we are
1015 			 * doing a normal disconnection.
1016 			 */
1017 			nexus->state = SFAS_NS_DISCONNECTED;
1018 
1019 			dev->sc_units_disconnected++;
1020 			break;
1021 
1022 		case SFAS_NS_RESET:
1023 			/*
1024 			 * We were reseting this SCSI-unit. Clean up the
1025 			 * nexus struct.
1026 			 */
1027 			dev->sc_led(dev, 0);
1028 			sfas_init_nexus(dev, nexus);
1029 			break;
1030 
1031 		default:
1032 			/*
1033 			 * Unexpected disconnection! Cleanup and exit. This
1034 			 * shouldn't cause any problems.
1035 			 */
1036 			printf("sfasintr: Unexpected disconnection\n");
1037 			printf("sfasintr: u %x s %d p %d f %x c %x\n",
1038 			       nexus->lun_unit, nexus->state,
1039 			       dev->sc_status & SFAS_STAT_PHASE_MASK,
1040 			       nexus->flags, nexus->cbuf[0]);
1041 
1042 			nexus->xs->resid = dev->sc_len;
1043 
1044 			nexus->flags &= ~SFAS_NF_UNIT_BUSY;
1045 			nexus->state = SFAS_NS_FINISHED;
1046 			nexus->status = -3;
1047 
1048 			dev->sc_led(dev, 0);
1049 			break;
1050 		}
1051 
1052 		/*
1053 		 * If we have disconnected units, we MUST enable reselection
1054 		 * within 250ms.
1055 		 */
1056 		if (dev->sc_units_disconnected &&
1057 		    !(dev->sc_flags & SFAS_ACTIVE))
1058 			*rp->sfas_command = SFAS_CMD_ENABLE_RESEL;
1059 
1060 		splx(s);
1061 
1062 		/* Select the first pre-initialized nexus we find. */
1063 		for(i=0; i<8; i++)
1064 			if (dev->sc_nexus[i].flags & (SFAS_NF_SELECT_ME | SFAS_NF_RETRY_SELECT))
1065 				if (sfas_select_unit(dev, i) == 2)
1066 					break;
1067 
1068 		/* We are done with this nexus! */
1069 		if (nexus->state == SFAS_NS_FINISHED)
1070 			sfas_scsidone(dev, nexus->xs, nexus->status);
1071 
1072 		return(1);
1073 	}
1074 
1075 	switch(nexus->state) {
1076 	case SFAS_NS_SELECTED:
1077 		dev->sc_cur_nexus = nexus;
1078 		dev->sc_sel_nexus = 0;
1079 
1080 		nexus->flags &= ~SFAS_NF_SELECT_ME;
1081 
1082 		/*
1083 		 * We have selected a unit. Setup chip, restore pointers and
1084 		 * light the led.
1085 		 */
1086 		*rp->sfas_syncper = nexus->syncper;
1087 		*rp->sfas_syncoff = nexus->syncoff;
1088 		*rp->sfas_config3 = nexus->config3;
1089 
1090 		sfas_restore_pointers(dev);
1091 
1092 		nexus->status	= 0xFF;
1093 		dev->sc_msg_in[0] = 0xFF;
1094 		dev->sc_msg_in_len= 0;
1095 
1096 		dev->sc_led(dev, 1);
1097 
1098 		break;
1099 
1100 	case SFAS_NS_DATA_IN:
1101 	case SFAS_NS_DATA_OUT:
1102 		/* We have transfered data. */
1103 		if (dev->sc_dma_len)
1104 			if (dev->sc_cur_link < dev->sc_max_link) {
1105 				/*
1106 				 * Clean up dma and at the same time get how
1107 				 * many bytes that were NOT transfered.
1108 				 */
1109 			  left = dev->sc_setup_dma(dev, 0, 0, SFAS_DMA_CLEAR);
1110 			  len  = dev->sc_dma_len;
1111 
1112 			  if (nexus->state == SFAS_NS_DATA_IN) {
1113 			    /*
1114 			     * If we were bumping we may have had an odd length
1115 			     * which means that there may be bytes left in the
1116 			     * fifo. We also need to move the data from the
1117 			     * bump buffer to the actual memory.
1118 			     */
1119 			    if (dev->sc_dma_buf == dev->sc_bump_pa)
1120 			    {
1121 			      while((*rp->sfas_fifo_flags&SFAS_FIFO_COUNT_MASK)
1122 				    && left)
1123 				dev->sc_bump_va[len-(left--)] = *rp->sfas_fifo;
1124 
1125 			      bcopy(dev->sc_bump_va, dev->sc_buf, len-left);
1126 			    }
1127 			  } else {
1128 			    /* Count any unsent bytes and flush them. */
1129 			    left+= *rp->sfas_fifo_flags & SFAS_FIFO_COUNT_MASK;
1130 			    *rp->sfas_command = SFAS_CMD_FLUSH_FIFO;
1131 			  }
1132 
1133 			  /*
1134 			   * Update pointers/length to reflect the transfered
1135 			   * data.
1136 			   */
1137 			  dev->sc_len -= len-left;
1138 			  dev->sc_buf += len-left;
1139 
1140 			  dev->sc_dma_buf += len-left;
1141 			  dev->sc_dma_len  = left;
1142 
1143 			  dev->sc_dma_blk_ptr += len-left;
1144 			  dev->sc_dma_blk_len -= len-left;
1145 
1146 			  /*
1147 			   * If it was the end of a dma block, we select the
1148 			   * next to begin with.
1149 			   */
1150 			  if (!dev->sc_dma_blk_len)
1151 			    dev->sc_cur_link++;
1152 			}
1153 		break;
1154 
1155 	case SFAS_NS_STATUS:
1156 		/*
1157 		 * If we were not sensing, grab the status byte. If we were
1158 		 * sensing and we got a bad status, let the user know.
1159 		 */
1160 
1161 		status = *rp->sfas_fifo;
1162 		msg = *rp->sfas_fifo;
1163 
1164 		nexus->status = status;
1165 		if (status != 0)
1166 			nexus->status = -1;
1167 
1168 		/*
1169 		 * Preload the command complete message. Handeled in
1170 		 * sfas_postaction.
1171 		 */
1172 		dev->sc_msg_in[0] = msg;
1173 		dev->sc_msg_in_len = 1;
1174 		nexus->flags |= SFAS_NF_HAS_MSG;
1175 		break;
1176 
1177 	default:
1178 		break;
1179 	}
1180 
1181 	return(0);
1182 }
1183 
1184 /*
1185  * Part three of the interrupt machine. Handle phase changes (and repeated
1186  * phase passes). We know that we have an active nexus here.
1187  */
1188 int
1189 sfas_postaction(dev, rp, nexus)
1190 	struct sfas_softc *dev;
1191 	sfas_regmap_p	  rp;
1192 	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 			  bcopy(dev->sc_buf, dev->sc_bump_va, 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 adress 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 withing 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(dev)
1515 	struct sfas_softc *dev;
1516 {
1517 	sfas_regmap_p	 rp;
1518 	struct nexus	*nexus;
1519 
1520 	rp = dev->sc_fas;
1521 
1522 	if (!sfas_pretests(dev, rp)) {
1523 
1524 		nexus = dev->sc_cur_nexus;
1525 		if (nexus == NULL)
1526 			nexus = dev->sc_sel_nexus;
1527 
1528 		if (nexus)
1529 			if (!sfas_midaction(dev, rp, nexus))
1530 				sfas_postaction(dev, rp, nexus);
1531 	}
1532 }
1533 
1534 /*
1535  * sfasicmd is used to perform IO when we can't use interrupts. sfasicmd
1536  * emulates the normal environment by waiting for the chip and calling
1537  * sfasintr.
1538  */
1539 void
1540 sfasicmd(dev, pendp)
1541 	struct sfas_softc   *dev;
1542 	struct sfas_pending *pendp;
1543 {
1544 	sfas_regmap_p	 rp;
1545 	struct nexus	*nexus;
1546 
1547 	nexus = &dev->sc_nexus[pendp->xs->xs_periph->periph_target];
1548 	rp = dev->sc_fas;
1549 
1550 	if (!sfasselect(dev, pendp, (char *)pendp->xs->cmd, pendp->xs->cmdlen,
1551 			(char *)pendp->xs->data, pendp->xs->datalen,
1552 			SFAS_SELECT_I))
1553 		panic("sfasicmd: Couldn't select unit");
1554 
1555 	while(nexus->state != SFAS_NS_FINISHED) {
1556 		sfasiwait(dev);
1557 		sfasintr(dev);
1558 	}
1559 
1560 	nexus->flags &= ~SFAS_NF_SYNC_TESTED;
1561 }
1562 
1563 
1564 #ifdef SFAS_DEBUG
1565 
1566 void
1567 dump_nexus(nexus)
1568 	struct nexus *nexus;
1569 {
1570 	int loop;
1571 
1572 	printf("nexus=%08x\n", (u_int)nexus);
1573 	printf("scsi_fer=%08x\n", (u_int)nexus->xs);
1574 	printf("ID=%02x\n", nexus->ID);
1575 	printf("clen=%02x\n", nexus->clen);
1576 	printf("cbuf=");
1577 	for (loop = 0; loop< 14; ++loop)
1578 		printf(" %02x\n", nexus->cbuf[loop]);
1579 	printf("\n");
1580 	printf("dma:\n");
1581 	for (loop = 0; loop < MAXCHAIN; ++loop)
1582 		printf("dma_chain: %08x %04x %04x\n", nexus->dma[loop].ptr,
1583 		    nexus->dma[loop].len, nexus->dma[loop].flg);
1584 	printf("\n");
1585 
1586 	printf("max_link=%d\n", nexus->max_link);
1587 	printf("cur_link=%d\n", nexus->cur_link);
1588 
1589 	printf("buf=%08x\n", (u_int)nexus->buf);
1590 	printf("len=%08x\n", nexus->len);
1591 	printf("dma_buf=%08x\n", (u_int)nexus->dma_buf);
1592 	printf("dma_len=%08x\n", nexus->dma_len);
1593 	printf("dma_blk_ptr=%08x\n", (u_int)nexus->dma_blk_ptr);
1594 	printf("dma_blk_len=%08x\n", nexus->dma_blk_len);
1595 	printf("dma_blk_flag=%08x\n", nexus->dma_blk_flg);
1596 	printf("state=%02x\n", nexus->state);
1597 	printf("flags=%04x\n", nexus->flags);
1598 	printf("period=%d\n", nexus->period);
1599 	printf("offset=%d\n", nexus->offset);
1600 	printf("syncper=%d\n", nexus->syncper);
1601 	printf("syncoff=%d\n", nexus->syncoff);
1602 	printf("config3=%02x\n", nexus->config3);
1603 	printf("lun_unit=%d\n", nexus->lun_unit);
1604 	printf("status=%02x\n", nexus->status);
1605 	printf("\n");
1606 }
1607 
1608 void
1609 dump_nexii(sc)
1610 	struct sfas_softc *sc;
1611 {
1612 	int loop;
1613 
1614 	for (loop = 0; loop < 8; ++loop) {
1615 		dump_nexus(&sc->sc_nexus[loop]);
1616 	}
1617 }
1618 
1619 void
1620 dump_sfassoftc(sc)
1621 	struct sfas_softc *sc;
1622 {
1623 	printf("sfassoftc @ 0x%08x\n", (u_int)sc);
1624 	printf("clock_freq = %d\n", sc->sc_clock_freq);
1625 	printf("timeout = %d\n", sc->sc_timeout);
1626 	printf("host_id = %d\n", sc->sc_host_id);
1627 	printf("config_flags = 0x%08x\n", sc->sc_config_flags);
1628 	printf("led_status = %d\n", sc->sc_led_status);
1629 
1630 	dump_nexii(sc);
1631 	printf("cur_nexus = 0x%08x\n", (u_int)sc->sc_cur_nexus);
1632 	printf("sel_nexus = 0x%08x\n", (u_int)sc->sc_sel_nexus);
1633 	printf("\n");
1634 }
1635 
1636 #endif	/* SFAS_DEBUG */
1637