xref: /netbsd-src/sys/arch/acorn32/podulebus/esc.c (revision 8324be4c9b4069049ae6d55cdb253887a4478026)
1 /*	$NetBSD: esc.c,v 1.34 2021/08/21 11:55:24 andvar 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  * AMD AM53CF94 scsi adaptor driver
78  *
79  * Functionally compatible with the FAS216
80  *
81  * Apart from a very small patch to set up control register 4
82  */
83 
84 /*
85  * Modified for NetBSD/arm32 by Scott Stevens
86  */
87 
88 #include <sys/cdefs.h>
89 __KERNEL_RCSID(0, "$NetBSD: esc.c,v 1.34 2021/08/21 11:55:24 andvar Exp $");
90 
91 #include <sys/param.h>
92 #include <sys/systm.h>
93 #include <sys/device.h>
94 #include <sys/buf.h>
95 #include <sys/proc.h>
96 #include <dev/scsipi/scsi_all.h>
97 #include <dev/scsipi/scsipi_all.h>
98 #include <dev/scsipi/scsiconf.h>
99 
100 #include <uvm/uvm_extern.h>
101 
102 #include <machine/pmap.h>
103 #include <machine/cpu.h>
104 #include <machine/io.h>
105 #include <machine/intr.h>
106 #include <acorn32/podulebus/podulebus.h>
107 #include <acorn32/podulebus/escreg.h>
108 #include <acorn32/podulebus/escvar.h>
109 
110 void escinitialize(struct esc_softc *);
111 void esc_minphys(struct buf *bp);
112 void esc_scsi_request(struct scsipi_channel *,
113 				scsipi_adapter_req_t, void *);
114 void esc_donextcmd(struct esc_softc *dev, struct esc_pending *pendp);
115 void esc_scsidone(struct esc_softc *dev, struct scsipi_xfer *xs,
116 			 int stat);
117 void escintr(struct esc_softc *dev);
118 void esciwait(struct esc_softc *dev);
119 void escreset(struct esc_softc *dev, int how);
120 int  escselect(struct esc_softc *dev, struct esc_pending *pendp,
121 			 unsigned char *cbuf, int clen,
122 			 unsigned char *buf, int len, int mode);
123 void escicmd(struct esc_softc *dev, struct esc_pending *pendp);
124 int escgo(struct esc_softc *dev, struct esc_pending *pendp);
125 
126 void esc_init_nexus(struct esc_softc *, struct nexus *);
127 void esc_save_pointers(struct esc_softc *);
128 void esc_restore_pointers(struct esc_softc *);
129 void esc_ixfer(struct esc_softc *);
130 void esc_build_sdtrm(struct esc_softc *, int, int);
131 int esc_select_unit(struct esc_softc *,	short);
132 struct nexus *esc_arbitate_target(struct esc_softc *, int);
133 void esc_setup_nexus(struct esc_softc *, struct nexus *, struct esc_pending *,
134     unsigned char *, int, unsigned char *, int, int);
135 int esc_pretests(struct esc_softc *, esc_regmap_p);
136 int esc_midaction(struct esc_softc *, esc_regmap_p, struct nexus *);
137 int esc_postaction(struct esc_softc *, esc_regmap_p, struct nexus *);
138 
139 
140 /*
141  * Initialize these to make 'em patchable. Defaults to enable sync and discon.
142  */
143 u_char	esc_inhibit_sync[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
144 u_char	esc_inhibit_disc[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
145 
146 #undef DEBUG
147 #define DEBUG
148 #ifdef DEBUG
149 #define QPRINTF(a) if (esc_debug > 1) printf a
150 int	esc_debug = 2;
151 #else
152 #define QPRINTF
153 #endif
154 
155 /*
156  * default minphys routine for esc based controllers
157  */
158 void
esc_minphys(struct buf * bp)159 esc_minphys(struct buf *bp)
160 {
161 
162 	/*
163 	 * No max transfer at this level.
164 	 */
165 	minphys(bp);
166 }
167 
168 /*
169  * Initialize the nexus structs.
170  */
171 void
esc_init_nexus(struct esc_softc * dev,struct nexus * nexus)172 esc_init_nexus(struct esc_softc *dev, struct nexus *nexus)
173 {
174 	memset(nexus, 0, sizeof(struct nexus));
175 
176 	nexus->state	= ESC_NS_IDLE;
177 	nexus->period	= 200;
178 	nexus->offset	= 0;
179 	nexus->syncper	= 5;
180 	nexus->syncoff	= 0;
181 	nexus->config3	= dev->sc_config3 & ~ESC_CFG3_FASTSCSI;
182 }
183 
184 void
escinitialize(struct esc_softc * dev)185 escinitialize(struct esc_softc *dev)
186 {
187 	int		 i;
188 
189 	dev->sc_led_status = 0;
190 
191 	TAILQ_INIT(&dev->sc_xs_pending);
192 	TAILQ_INIT(&dev->sc_xs_free);
193 
194 /*
195  * Initialize the esc_pending structs and link them into the free list. We
196  * have to set vm_link_data.pages to 0 or the vm FIX won't work.
197  */
198 	for(i=0; i<MAXPENDING; i++) {
199 		TAILQ_INSERT_TAIL(&dev->sc_xs_free, &dev->sc_xs_store[i],
200 				  link);
201 	}
202 
203 /*
204  * Calculate the correct clock conversion factor 2 <= factor <= 8, i.e. set
205  * the factor to clock_freq / 5 (int).
206  */
207 	if (dev->sc_clock_freq <= 10)
208 		dev->sc_clock_conv_fact = 2;
209 	if (dev->sc_clock_freq <= 40)
210 		dev->sc_clock_conv_fact = 2+((dev->sc_clock_freq-10)/5);
211 	else
212 		panic("escinitialize: Clock frequency too high");
213 
214 /* Setup and save the basic configuration registers */
215 	dev->sc_config1 = (dev->sc_host_id & ESC_CFG1_BUS_ID_MASK);
216 	dev->sc_config2 = ESC_CFG2_FEATURES_ENABLE;
217 	dev->sc_config3 = (dev->sc_clock_freq > 25 ? ESC_CFG3_FASTCLK : 0);
218 
219 /* Precalculate timeout value and clock period. */
220 /* Ekkk ... floating point in the kernel !!!! */
221 /*	dev->sc_timeout_val  = 1+dev->sc_timeout*dev->sc_clock_freq/
222 				 (7.682*dev->sc_clock_conv_fact);*/
223 	dev->sc_timeout_val  = 1+dev->sc_timeout*dev->sc_clock_freq/
224 				 ((7682*dev->sc_clock_conv_fact)/1000);
225 	dev->sc_clock_period = 1000/dev->sc_clock_freq;
226 
227 	escreset(dev, 1 | 2);	/* Reset Chip and Bus */
228 
229 	dev->sc_units_disconnected = 0;
230 	dev->sc_msg_in_len = 0;
231 	dev->sc_msg_out_len = 0;
232 
233 	dev->sc_flags = 0;
234 
235 	for(i=0; i<8; i++)
236 		esc_init_nexus(dev, &dev->sc_nexus[i]);
237 
238 /*
239  * Setup bump buffer.
240  */
241 	dev->sc_bump_va = (u_char *)uvm_km_alloc(kernel_map, dev->sc_bump_sz, 0,
242 	    UVM_KMF_WIRED | UVM_KMF_ZERO);
243 	(void) pmap_extract(pmap_kernel(), (vaddr_t)dev->sc_bump_va,
244 	    (paddr_t *)&dev->sc_bump_pa);
245 
246 /*
247  * Setup pages to noncachable, that way we don't have to flush the cache
248  * every time we need "bumped" transfer.
249  */
250 	pt_entry_t * const ptep = vtopte((vaddr_t) dev->sc_bump_va);
251 	const pt_entry_t opte = *ptep;
252 	const pt_entry_t npte = opte & ~L2_C;
253 	l2pte_set(ptep, npte, opte);
254 	PTE_SYNC(ptep);
255 	cpu_tlb_flushD();
256 	cpu_dcache_wbinv_range((vaddr_t)dev->sc_bump_va, PAGE_SIZE);
257 
258 	printf(" dmabuf V0x%08x P0x%08x", (u_int)dev->sc_bump_va, (u_int)dev->sc_bump_pa);
259 }
260 
261 
262 /*
263  * used by specific esc controller
264  */
265 void
esc_scsi_request(struct scsipi_channel * chan,scsipi_adapter_req_t req,void * arg)266 esc_scsi_request(struct scsipi_channel *chan, scsipi_adapter_req_t req,
267  								void *arg)
268 {
269 	struct scsipi_xfer *xs;
270 	struct esc_softc	*dev = device_private(chan->chan_adapter->adapt_dev);
271 	struct scsipi_periph	*periph;
272 	struct esc_pending	*pendp;
273 	int			 flags, s, target;
274 
275 	switch (req) {
276 	case ADAPTER_REQ_RUN_XFER:
277 		xs = arg;
278 		periph = xs->xs_periph;
279 		flags = xs->xs_control;
280 		target = periph->periph_target;
281 
282 		if (flags & XS_CTL_DATA_UIO)
283 			panic("esc: scsi data uio requested");
284 
285 		if ((flags & XS_CTL_POLL) && (dev->sc_flags & ESC_ACTIVE))
286 			panic("esc_scsicmd: busy");
287 
288 /* Get hold of a esc_pending block. */
289 		s = splbio();
290 		pendp = dev->sc_xs_free.tqh_first;
291 		if (pendp == NULL) {
292 			splx(s);
293 			xs->error = XS_RESOURCE_SHORTAGE;
294 			scsipi_done(xs);
295 			return;
296 		}
297 		TAILQ_REMOVE(&dev->sc_xs_free, pendp, link);
298 		pendp->xs = xs;
299 		splx(s);
300 
301 
302 /* If the chip if busy OR the unit is busy, we have to wait for out turn. */
303 		if ((dev->sc_flags & ESC_ACTIVE) ||
304 		    (dev->sc_nexus[target].flags & ESC_NF_UNIT_BUSY)) {
305 			s = splbio();
306 			TAILQ_INSERT_TAIL(&dev->sc_xs_pending, pendp, link);
307 			splx(s);
308 		} else
309 			esc_donextcmd(dev, pendp);
310 
311 		return;
312 	case ADAPTER_REQ_GROW_RESOURCES:
313 	case ADAPTER_REQ_SET_XFER_MODE:
314 		/* XXX Not supported. */
315 		return;
316 	}
317 
318 }
319 
320 /*
321  * Actually select the unit, whereby the whole scsi-process is started.
322  */
323 void
esc_donextcmd(struct esc_softc * dev,struct esc_pending * pendp)324 esc_donextcmd(struct esc_softc *dev, struct esc_pending *pendp)
325 {
326 	int	s;
327 
328 /*
329  * Special case for scsi unit reset. I think this is waterproof. We first
330  * select the unit during splbio. We then cycle through the generated
331  * interrupts until the interrupt routine signals that the unit has
332  * acknowledged the reset. After that we have to wait a reset to select
333  * delay before anything else can happen.
334  */
335 	if (pendp->xs->xs_control & XS_CTL_RESET) {
336 		struct nexus	*nexus;
337 
338 		s = splbio();
339 		while(!escselect(dev, pendp, 0, 0, 0, 0, ESC_SELECT_K)) {
340 			splx(s);
341 			delay(10);
342 			s = splbio();
343 		}
344 
345 		nexus = dev->sc_cur_nexus;
346 		while(nexus->flags & ESC_NF_UNIT_BUSY) {
347 			esciwait(dev);
348 			escintr(dev);
349 		}
350 
351 		nexus->flags |= ESC_NF_UNIT_BUSY;
352 		splx(s);
353 
354 		escreset(dev, 0);
355 
356 		s = splbio();
357 		nexus->flags &= ~ESC_NF_UNIT_BUSY;
358 		splx(s);
359 	}
360 
361 /*
362  * If we are polling, go to splbio and perform the command, else we poke
363  * the scsi-bus via escgo to get the interrupt machine going.
364  */
365 	if (pendp->xs->xs_control & XS_CTL_POLL) {
366 		s = splbio();
367 		escicmd(dev, pendp);
368 		TAILQ_INSERT_TAIL(&dev->sc_xs_free, pendp, link);
369 		splx(s);
370 	} else {
371 		escgo(dev, pendp);
372 		return;
373 	}
374 }
375 
376 void
esc_scsidone(struct esc_softc * dev,struct scsipi_xfer * xs,int stat)377 esc_scsidone(struct esc_softc *dev, struct scsipi_xfer *xs, int stat)
378 {
379 	struct esc_pending	*pendp;
380 	int			 s;
381 
382 	xs->status = stat;
383 
384 	if (stat == 0)
385 		xs->resid = 0;
386 	else {
387 		switch(stat) {
388 		case SCSI_CHECK:
389 		case SCSI_BUSY:
390 			xs->error = XS_BUSY;
391 			break;
392 		case -1:
393 			xs->error = XS_DRIVER_STUFFUP;
394 			QPRINTF(("esc_scsicmd() bad %x\n", stat));
395 			break;
396 		default:
397 			xs->error = XS_TIMEOUT;
398 			break;
399 		}
400 	}
401 
402 /* Steal the next command from the queue so that one unit can't hog the bus. */
403 	s = splbio();
404 	pendp = dev->sc_xs_pending.tqh_first;
405 	while(pendp) {
406 		if (!(dev->sc_nexus[pendp->xs->xs_periph->periph_target].flags &
407 		      ESC_NF_UNIT_BUSY))
408 			break;
409 		pendp = pendp->link.tqe_next;
410 	}
411 
412 	if (pendp != NULL) {
413 		TAILQ_REMOVE(&dev->sc_xs_pending, pendp, link);
414 	}
415 
416 	splx(s);
417 	scsipi_done(xs);
418 
419 	if (pendp)
420 		esc_donextcmd(dev, pendp);
421 }
422 
423 /*
424  * There are two kinds of reset:
425  *  1) CHIP-bus reset. This also implies a SCSI-bus reset.
426  *  2) SCSI-bus reset.
427  * After the appropriate resets have been performed we wait a reset to select
428  * delay time.
429  */
430 void
escreset(struct esc_softc * dev,int how)431 escreset(struct esc_softc *dev, int how)
432 {
433 	esc_regmap_p	rp;
434 	int		i, s;
435 
436 	rp = dev->sc_esc;
437 
438 	if (how & 1) {
439 		for(i=0; i<8; i++)
440 			esc_init_nexus(dev, &dev->sc_nexus[i]);
441 
442 		*rp->esc_command = ESC_CMD_RESET_CHIP;
443 		delay(1);
444 		*rp->esc_command = ESC_CMD_NOP;
445 
446 		*rp->esc_config1 = dev->sc_config1;
447 		*rp->esc_config2 = dev->sc_config2;
448 		*rp->esc_config3 = dev->sc_config3;
449 		*rp->esc_config4 = dev->sc_config4;
450 		*rp->esc_timeout = dev->sc_timeout_val;
451 		*rp->esc_clkconv = dev->sc_clock_conv_fact &
452 					ESC_CLOCK_CONVERSION_MASK;
453 	}
454 
455 	if (how & 2) {
456 		for(i=0; i<8; i++)
457 			esc_init_nexus(dev, &dev->sc_nexus[i]);
458 
459 		s = splbio();
460 
461 		*rp->esc_command = ESC_CMD_RESET_SCSI_BUS;
462 		delay(100);
463 
464 /* Skip interrupt generated by RESET_SCSI_BUS */
465 		while(*rp->esc_status & ESC_STAT_INTERRUPT_PENDING) {
466 			dev->sc_status = *rp->esc_status;
467 			dev->sc_interrupt = *rp->esc_interrupt;
468 
469 			delay(100);
470 		}
471 
472 		dev->sc_status = *rp->esc_status;
473 		dev->sc_interrupt = *rp->esc_interrupt;
474 
475 		splx(s);
476 	}
477 
478 	if (dev->sc_config_flags & ESC_SLOW_START)
479 		delay(4*250000); /* RESET to SELECT DELAY*4 for slow devices */
480 	else
481 		delay(250000);	 /* RESET to SELECT DELAY */
482 }
483 
484 /*
485  * Save active data pointers to the nexus block currently active.
486  */
487 void
esc_save_pointers(struct esc_softc * dev)488 esc_save_pointers(struct esc_softc *dev)
489 {
490 	struct nexus	*nx;
491 
492 	nx = dev->sc_cur_nexus;
493 	if (nx) {
494 		nx->cur_link	= dev->sc_cur_link;
495 		nx->max_link	= dev->sc_max_link;
496 		nx->buf		= dev->sc_buf;
497 		nx->len		= dev->sc_len;
498 		nx->dma_len	= dev->sc_dma_len;
499 		nx->dma_buf	= dev->sc_dma_buf;
500 		nx->dma_blk_flg	= dev->sc_dma_blk_flg;
501 		nx->dma_blk_len	= dev->sc_dma_blk_len;
502 		nx->dma_blk_ptr	= dev->sc_dma_blk_ptr;
503 	}
504 }
505 
506 /*
507  * Restore data pointers from the currently active nexus block.
508  */
509 void
esc_restore_pointers(struct esc_softc * dev)510 esc_restore_pointers(struct esc_softc *dev)
511 {
512 	struct nexus	*nx;
513 
514 	nx = dev->sc_cur_nexus;
515 	if (nx) {
516 		dev->sc_cur_link    = nx->cur_link;
517 		dev->sc_max_link    = nx->max_link;
518 		dev->sc_buf	    = nx->buf;
519 		dev->sc_len	    = nx->len;
520 		dev->sc_dma_len	    = nx->dma_len;
521 		dev->sc_dma_buf	    = nx->dma_buf;
522 		dev->sc_dma_blk_flg = nx->dma_blk_flg;
523 		dev->sc_dma_blk_len = nx->dma_blk_len;
524 		dev->sc_dma_blk_ptr = nx->dma_blk_ptr;
525 		dev->sc_chain	    = nx->dma;
526 		dev->sc_unit	    = (nx->lun_unit & 0x0F);
527 		dev->sc_lun	    = (nx->lun_unit & 0xF0) >> 4;
528 	}
529 }
530 
531 /*
532  * esciwait is used during interrupt and polled IO to wait for an event from
533  * the FAS chip. This function MUST NOT BE CALLED without interrupt disabled.
534  */
535 void
esciwait(struct esc_softc * dev)536 esciwait(struct esc_softc *dev)
537 {
538 	esc_regmap_p	rp;
539 
540 /*
541  * If ESC_DONT_WAIT is set, we have already grabbed the interrupt info
542  * elsewhere. So we don't have to wait for it.
543  */
544 	if (dev->sc_flags & ESC_DONT_WAIT) {
545 		dev->sc_flags &= ~ESC_DONT_WAIT;
546 		return;
547 	}
548 
549 	rp = dev->sc_esc;
550 
551 /* Wait for FAS chip to signal an interrupt. */
552 	while(!(*rp->esc_status & ESC_STAT_INTERRUPT_PENDING));
553 /*		delay(1);*/
554 
555 /* Grab interrupt info from chip. */
556 	dev->sc_status = *rp->esc_status;
557 	dev->sc_interrupt = *rp->esc_interrupt;
558 	if (dev->sc_interrupt & ESC_INT_RESELECTED) {
559 		dev->sc_resel[0] = *rp->esc_fifo;
560 		dev->sc_resel[1] = *rp->esc_fifo;
561 	}
562 }
563 
564 #if 0
565 /*
566  * Transfer info to/from device. esc_ixfer uses polled IO+esciwait so the
567  * rules that apply to esciwait also applies here.
568  */
569 void
570 esc_ixfer(struct esc_softc *dev)
571 {
572 	esc_regmap_p	 rp;
573 	u_char		*buf;
574 	int		 len, mode, phase;
575 
576 	rp = dev->sc_esc;
577 	buf = dev->sc_buf;
578 	len = dev->sc_len;
579 
580 /*
581  * Decode the scsi phase to determine whether we are reading or writing.
582  * mode == 1 => READ, mode == 0 => WRITE
583  */
584 	phase = dev->sc_status & ESC_STAT_PHASE_MASK;
585 	mode = (phase == ESC_PHASE_DATA_IN);
586 
587 	while(len && ((dev->sc_status & ESC_STAT_PHASE_MASK) == phase))
588 		if (mode) {
589 			*rp->esc_command = ESC_CMD_TRANSFER_INFO;
590 
591 			esciwait(dev);
592 
593 			*buf++ = *rp->esc_fifo;
594 			len--;
595 		} else {
596 			len--;
597 			*rp->esc_fifo = *buf++;
598 			*rp->esc_command = ESC_CMD_TRANSFER_INFO;
599 
600 			esciwait(dev);
601 		}
602 
603 /* Update buffer pointers to reflect the sent/received data. */
604 	dev->sc_buf = buf;
605 	dev->sc_len = len;
606 
607 /*
608  * Since the last esciwait will be a phase-change, we can't wait for it
609  * again later, so we have to signal that.
610  */
611 
612 	dev->sc_flags |= ESC_DONT_WAIT;
613 }
614 #else
615 /*
616  * Transfer info to/from device. esc_ixfer uses polled IO+esciwait so the
617  * rules that apply to esciwait also applies here.
618  */
619 void
esc_ixfer(struct esc_softc * dev)620 esc_ixfer(struct esc_softc *dev)
621 {
622 	esc_regmap_p	 rp;
623 	vu_char		*esc_status;
624 	vu_char		*esc_command;
625 	vu_char		*esc_interrupt;
626 	vu_char		*esc_fifo;
627 	u_char		*buf;
628 	int		 len, mode, phase;
629 
630 	rp = dev->sc_esc;
631 	buf = dev->sc_buf;
632 	len = dev->sc_len;
633 
634 	/* Use discrete variables for better optimisation */
635 
636 	esc_status = rp->esc_status;
637 	esc_command = rp->esc_command;
638 	esc_interrupt = rp->esc_interrupt;
639 	esc_fifo = rp->esc_fifo;
640 
641 /*
642  * Decode the scsi phase to determine whether we are reading or writing.
643  * mode == 1 => READ, mode == 0 => WRITE
644  */
645 	phase = dev->sc_status & ESC_STAT_PHASE_MASK;
646 	mode = (phase == ESC_PHASE_DATA_IN);
647 
648 	if (mode) {
649 		while(len && ((dev->sc_status & ESC_STAT_PHASE_MASK) == phase)) {
650 			*esc_command = ESC_CMD_TRANSFER_INFO;
651 
652 			/* Wait for FAS chip to signal an interrupt. */
653 			while(!(*esc_status & ESC_STAT_INTERRUPT_PENDING));
654 /*				delay(1);*/
655 
656 			/* Grab interrupt info from chip. */
657 			dev->sc_status = *esc_status;
658 			dev->sc_interrupt = *esc_interrupt;
659 
660 			*buf++ = *esc_fifo;
661 			len--;
662 		}
663 	} else {
664 		while(len && ((dev->sc_status & ESC_STAT_PHASE_MASK) == phase)) {
665 			len--;
666 			*esc_fifo = *buf++;
667 			*esc_command = ESC_CMD_TRANSFER_INFO;
668 
669 			/* Wait for FAS chip to signal an interrupt. */
670 			while(!(*esc_status & ESC_STAT_INTERRUPT_PENDING));
671 /*				delay(1);*/
672 
673 			/* Grab interrupt info from chip. */
674 			dev->sc_status = *esc_status;
675 			dev->sc_interrupt = *esc_interrupt;
676 		}
677 	}
678 
679 /* Update buffer pointers to reflect the sent/received data. */
680 	dev->sc_buf = buf;
681 	dev->sc_len = len;
682 
683 /*
684  * Since the last esciwait will be a phase-change, we can't wait for it
685  * again later, so we have to signal that.
686  */
687 
688 	dev->sc_flags |= ESC_DONT_WAIT;
689 }
690 #endif
691 
692 /*
693  * Build a Synchronous Data Transfer Request message
694  */
695 void
esc_build_sdtrm(struct esc_softc * dev,int period,int offset)696 esc_build_sdtrm(struct esc_softc *dev, int period, int offset)
697 {
698 	dev->sc_msg_out[0] = 0x01;
699 	dev->sc_msg_out[1] = 0x03;
700 	dev->sc_msg_out[2] = 0x01;
701 	dev->sc_msg_out[3] = period/4;
702 	dev->sc_msg_out[4] = offset;
703 	dev->sc_msg_out_len= 5;
704 }
705 
706 /*
707  * Arbitate the scsi bus and select the unit
708  */
709 int
esc_select_unit(struct esc_softc * dev,short target)710 esc_select_unit(struct esc_softc *dev, short target)
711 {
712 	esc_regmap_p	 rp;
713 	struct nexus	*nexus;
714 	int		 s, retcode, i;
715 	u_char		 cmd;
716 
717 	s = splbio();	/* Do this at splbio so that we won't be disturbed. */
718 
719 	retcode = 0;
720 
721 	nexus = &dev->sc_nexus[target];
722 
723 /*
724  * Check if the chip is busy. If not the we mark it as so and hope that nobody
725  * reselects us until we have grabbed the bus.
726  */
727 	if (!(dev->sc_flags & ESC_ACTIVE) && !dev->sc_sel_nexus) {
728 		dev->sc_flags |= ESC_ACTIVE;
729 
730 		rp = dev->sc_esc;
731 
732 		*rp->esc_syncper = nexus->syncper;
733 		*rp->esc_syncoff = nexus->syncoff;
734 		*rp->esc_config3 = nexus->config3;
735 
736 		*rp->esc_config1 = dev->sc_config1;
737 		*rp->esc_timeout = dev->sc_timeout_val;
738 		*rp->esc_dest_id = target;
739 
740 /* If nobody has stolen the bus, we can send a select command to the chip. */
741 		if (!(*rp->esc_status & ESC_STAT_INTERRUPT_PENDING)) {
742 			*rp->esc_fifo = nexus->ID;
743 			if ((nexus->flags & (ESC_NF_DO_SDTR | ESC_NF_RESET))
744 			    || (dev->sc_msg_out_len != 0))
745 				cmd = ESC_CMD_SEL_ATN_STOP;
746 			else {
747 				for(i=0; i<nexus->clen; i++)
748 					*rp->esc_fifo = nexus->cbuf[i];
749 
750 				cmd = ESC_CMD_SEL_ATN;
751 			}
752 
753 			dev->sc_sel_nexus = nexus;
754 
755 			*rp->esc_command = cmd;
756 			retcode = 1;
757 			nexus->flags &= ~ESC_NF_RETRY_SELECT;
758 		} else
759 			nexus->flags |= ESC_NF_RETRY_SELECT;
760 	} else
761 		nexus->flags |= ESC_NF_RETRY_SELECT;
762 
763 	splx(s);
764 	return(retcode);
765 }
766 
767 /*
768  * Grab the nexus if available else return 0.
769  */
770 struct nexus *
esc_arbitate_target(struct esc_softc * dev,int target)771 esc_arbitate_target(struct esc_softc *dev, int target)
772 {
773 	struct nexus	*nexus;
774 	int		 s;
775 
776 /*
777  * This is really simple. Raise interrupt level to splbio. Grab the nexus and
778  * leave.
779  */
780 	nexus = &dev->sc_nexus[target];
781 
782 	s = splbio();
783 
784 	if (nexus->flags & ESC_NF_UNIT_BUSY)
785 		nexus = 0;
786 	else
787 		nexus->flags |= ESC_NF_UNIT_BUSY;
788 
789 	splx(s);
790 	return(nexus);
791 }
792 
793 /*
794  * Setup a nexus for use. Initializes command, buffer pointers and DMA chain.
795  */
796 void
esc_setup_nexus(struct esc_softc * dev,struct nexus * nexus,struct esc_pending * pendp,unsigned char * cbuf,int clen,unsigned char * buf,int len,int mode)797 esc_setup_nexus(struct esc_softc *dev, struct nexus *nexus, struct esc_pending *pendp, unsigned char *cbuf, int clen, unsigned char *buf, int len, int mode)
798 {
799 	int	sync, target, lun;
800 
801 	target = pendp->xs->xs_periph->periph_target;
802 	lun    = pendp->xs->xs_periph->periph_lun;
803 
804 /*
805  * Adopt mode to reflect the config flags.
806  * If we can't use DMA we can't use synch transfer. Also check the
807  * esc_inhibit_xxx[target] flags.
808  */
809 	if ((dev->sc_config_flags & (ESC_NO_SYNCH | ESC_NO_DMA)) ||
810 	    esc_inhibit_sync[(int)target])
811 		mode &= ~ESC_SELECT_S;
812 
813 	if ((dev->sc_config_flags & ESC_NO_RESELECT) ||
814 	    esc_inhibit_disc[(int)target])
815 		mode &= ~ESC_SELECT_R;
816 
817 	nexus->xs		= pendp->xs;
818 
819 /* Setup the nexus struct. */
820 	nexus->ID	   = ((mode & ESC_SELECT_R) ? 0xC0 : 0x80) | lun;
821 	nexus->clen	   = clen;
822 	memcpy(nexus->cbuf, cbuf, nexus->clen);
823 	nexus->cbuf[1] |= lun << 5;		/* Fix the lun bits */
824 	nexus->cur_link	   = 0;
825 	nexus->dma_len	   = 0;
826 	nexus->dma_buf	   = 0;
827 	nexus->dma_blk_len = 0;
828 	nexus->dma_blk_ptr = 0;
829 	nexus->len	   = len;
830 	nexus->buf	   = buf;
831 	nexus->lun_unit	   = (lun << 4) | target;
832 	nexus->state	   = ESC_NS_SELECTED;
833 
834 /* We must keep these flags. All else must be zero. */
835 	nexus->flags	  &= ESC_NF_UNIT_BUSY
836 			   | ESC_NF_SYNC_TESTED | ESC_NF_SELECT_ME;
837 
838 	if (mode & ESC_SELECT_I)
839 		nexus->flags |= ESC_NF_IMMEDIATE;
840 	if (mode & ESC_SELECT_K)
841 		nexus->flags |= ESC_NF_RESET;
842 
843 	sync  = ((mode & ESC_SELECT_S) ? 1 : 0);
844 
845 /* We can't use sync during polled IO. */
846 	if (sync && (mode & ESC_SELECT_I))
847 		sync = 0;
848 
849 	if (!sync &&
850 	    ((nexus->flags & ESC_NF_SYNC_TESTED) && (nexus->offset != 0))) {
851 		/*
852 		 * If the scsi unit is set to synch transfer and we don't want
853 		 * that, we have to renegotiate.
854 		 */
855 
856 		nexus->flags |= ESC_NF_DO_SDTR;
857 		nexus->period = 200;
858 		nexus->offset = 0;
859 	} else if (sync && !(nexus->flags & ESC_NF_SYNC_TESTED)) {
860 		/*
861 		 * If the scsi unit is not set to synch transfer and we want
862 		 * that, we have to negotiate. This should really base the
863 		 * period on the clock frequency rather than just check if
864 		 * >25 MHz
865 		 */
866 
867 		nexus->flags |= ESC_NF_DO_SDTR;
868 		nexus->period = ((dev->sc_clock_freq>25) ? 100 : 200);
869 		nexus->offset = 8;
870 
871 		/* If the user has a long cable, we want to limit the period */
872 		if ((nexus->period == 100) &&
873 		    (dev->sc_config_flags & ESC_SLOW_CABLE))
874 			nexus->period = 200;
875 	}
876 
877 /*
878  * Fake a DMA-block for polled IO. This way we can use the same code to handle
879  * reselection. Much nicer this way.
880  */
881 	if ((mode & ESC_SELECT_I) || (dev->sc_config_flags & ESC_NO_DMA)) {
882 		nexus->dma[0].ptr = buf;
883 		nexus->dma[0].len = len;
884 		nexus->dma[0].flg = ESC_CHAIN_PRG;
885 		nexus->max_link   = 1;
886 	} else {
887 		nexus->max_link = dev->sc_build_dma_chain(dev, nexus->dma,
888 							  buf, len);
889 	}
890 
891 /* Flush the caches. */
892 
893 	if (len && !(mode & ESC_SELECT_I))
894 		cpu_dcache_wbinv_range((vaddr_t)buf, len);
895 }
896 
897 int
escselect(struct esc_softc * dev,struct esc_pending * pendp,unsigned char * cbuf,int clen,unsigned char * buf,int len,int mode)898 escselect(struct esc_softc *dev, struct esc_pending *pendp, unsigned char *cbuf, int clen, unsigned char *buf, int len, int mode)
899 {
900 	struct nexus	*nexus;
901 
902 /* Get the nexus struct. */
903 	nexus = esc_arbitate_target(dev, pendp->xs->xs_periph->periph_target);
904 	if (nexus == NULL)
905 		return(0);
906 
907 /* Setup the nexus struct. */
908 	esc_setup_nexus(dev, nexus, pendp, cbuf, clen, buf, len, mode);
909 
910 /* Post it to the interrupt machine. */
911 	esc_select_unit(dev, pendp->xs->xs_periph->periph_target);
912 
913 	return(1);
914 }
915 
916 int
escgo(struct esc_softc * dev,struct esc_pending * pendp)917 escgo(struct esc_softc *dev, struct esc_pending *pendp)
918 {
919 	int	 s;
920 	char	*buf;
921 
922 	buf    = pendp->xs->data;
923 
924 	if (escselect(dev, pendp, (char *)pendp->xs->cmd, pendp->xs->cmdlen,
925 		      buf, pendp->xs->datalen, ESC_SELECT_RS)) {
926 		/*
927 		 * We got the command going so the esc_pending struct is now
928 		 * free to reuse.
929 		 */
930 
931 		s = splbio();
932 		TAILQ_INSERT_TAIL(&dev->sc_xs_free, pendp, link);
933 		splx(s);
934 	} else {
935 		/*
936 		 * We couldn't make the command fly so we have to wait. The
937 		 * struct MUST be inserted at the head to keep the order of
938 		 * the commands.
939 		 */
940 
941 		s = splbio();
942 		TAILQ_INSERT_HEAD(&dev->sc_xs_pending, pendp, link);
943 		splx(s);
944 	}
945 
946 	return(0);
947 }
948 
949 /*
950  * Part one of the interrupt machine. Error checks and reselection test.
951  * We don't know if we have an active nexus here!
952  */
953 int
esc_pretests(struct esc_softc * dev,esc_regmap_p rp)954 esc_pretests(struct esc_softc *dev, esc_regmap_p rp)
955 {
956 	struct nexus	*nexus;
957 	int		 i, s;
958 
959 	if (dev->sc_interrupt & ESC_INT_SCSI_RESET_DETECTED) {
960 		/*
961 		 * Cleanup and notify user. Lets hope that this is all we
962 		 * have to do
963 		 */
964 
965 		for(i=0; i<8; i++) {
966 			if (dev->sc_nexus[i].xs)
967 				esc_scsidone(dev, dev->sc_nexus[i].xs, -2);
968 
969 			esc_init_nexus(dev, &dev->sc_nexus[i]);
970 		}
971 		printf("escintr: SCSI-RESET detected!");
972 		return(-1);
973 	}
974 
975 	if (dev->sc_interrupt & ESC_INT_ILLEGAL_COMMAND) {
976 		/* Something went terrible wrong! Dump some data and panic! */
977 
978 		printf("FIFO:");
979 		while(*rp->esc_fifo_flags & ESC_FIFO_COUNT_MASK)
980 			printf(" %x", *rp->esc_fifo);
981 		printf("\n");
982 
983 		printf("CMD: %x\n", *rp->esc_command);
984 		panic("escintr: ILLEGAL COMMAND!");
985 	}
986 
987 	if (dev->sc_interrupt & ESC_INT_RESELECTED) {
988 		/* We were reselected. Set the chip as busy */
989 
990 		s = splbio();
991 		dev->sc_flags |= ESC_ACTIVE;
992 		if (dev->sc_sel_nexus) {
993 			dev->sc_sel_nexus->flags |= ESC_NF_SELECT_ME;
994 			dev->sc_sel_nexus = 0;
995 		}
996 		splx(s);
997 
998 		if (dev->sc_units_disconnected) {
999 			/* Find out who reselected us. */
1000 
1001 			dev->sc_resel[0] &= ~(1<<dev->sc_host_id);
1002 
1003 			for(i=0; i<8; i++)
1004 				if (dev->sc_resel[0] & (1<<i))
1005 					break;
1006 
1007 			if (i == 8)
1008 				panic("Illegal reselection!");
1009 
1010 			if (dev->sc_nexus[i].state == ESC_NS_DISCONNECTED) {
1011 				/*
1012 				 * This unit had disconnected, so we reconnect
1013 				 * it.
1014 				 */
1015 
1016 				dev->sc_cur_nexus = &dev->sc_nexus[i];
1017 				nexus = dev->sc_cur_nexus;
1018 
1019 				*rp->esc_syncper = nexus->syncper;
1020 				*rp->esc_syncoff = nexus->syncoff;
1021 				*rp->esc_config3 = nexus->config3;
1022 
1023 				*rp->esc_dest_id = i & 7;
1024 
1025 				dev->sc_units_disconnected--;
1026 				dev->sc_msg_in_len= 0;
1027 
1028 				/* Restore active pointers. */
1029 				esc_restore_pointers(dev);
1030 
1031 				nexus->state = ESC_NS_RESELECTED;
1032 
1033 				*rp->esc_command = ESC_CMD_MESSAGE_ACCEPTED;
1034 
1035 				return(1);
1036 			}
1037 		}
1038 
1039 		/* Somehow we got an illegal reselection. Dump and panic. */
1040 		printf("escintr: resel[0] %x resel[1] %x disconnected %d\n",
1041 		       dev->sc_resel[0], dev->sc_resel[1],
1042 		       dev->sc_units_disconnected);
1043 		panic("escintr: Unexpected reselection!");
1044 	}
1045 
1046 	return(0);
1047 }
1048 
1049 /*
1050  * Part two of the interrupt machine. Handle disconnection and post command
1051  * processing. We know that we have an active nexus here.
1052  */
1053 int
esc_midaction(struct esc_softc * dev,esc_regmap_p rp,struct nexus * nexus)1054 esc_midaction(struct esc_softc *dev, esc_regmap_p rp, struct nexus *nexus)
1055 {
1056 	int	i, left, len, s;
1057 	u_char	status, msg;
1058 
1059 	if (dev->sc_interrupt & ESC_INT_DISCONNECT) {
1060 		s = splbio();
1061 		dev->sc_cur_nexus = 0;
1062 
1063 		/* Mark chip as busy and clean up the chip FIFO. */
1064 		dev->sc_flags &= ~ESC_ACTIVE;
1065 		*rp->esc_command = ESC_CMD_FLUSH_FIFO;
1066 
1067 		/* Let the nexus state reflect what we have to do. */
1068 		switch(nexus->state) {
1069 		case ESC_NS_SELECTED:
1070 			dev->sc_sel_nexus = 0;
1071 			nexus->flags &= ~ESC_NF_SELECT_ME;
1072 
1073 			/*
1074 			 * We were trying to select the unit. Probably no unit
1075 			 * at this ID.
1076 			 */
1077 			nexus->xs->resid = dev->sc_len;
1078 
1079 			nexus->status = -2;
1080 			nexus->flags &= ~ESC_NF_UNIT_BUSY;
1081 			nexus->state = ESC_NS_FINISHED;
1082 			break;
1083 
1084 		case ESC_NS_DONE:
1085 			/* All done. */
1086 			nexus->xs->resid = dev->sc_len;
1087 
1088 			nexus->flags &= ~ESC_NF_UNIT_BUSY;
1089 			nexus->state  = ESC_NS_FINISHED;
1090 			dev->sc_led(dev, 0);
1091 			break;
1092 
1093 		case ESC_NS_DISCONNECTING:
1094 			/*
1095 			 * We have received a DISCONNECT message, so we are
1096 			 * doing a normal disconnection.
1097 			 */
1098 			nexus->state = ESC_NS_DISCONNECTED;
1099 
1100 			dev->sc_units_disconnected++;
1101 			break;
1102 
1103 		case ESC_NS_RESET:
1104 			/*
1105 			 * We were resetting this SCSI-unit. Clean up the
1106 			 * nexus struct.
1107 			 */
1108 			dev->sc_led(dev, 0);
1109 			esc_init_nexus(dev, nexus);
1110 			break;
1111 
1112 		default:
1113 			/*
1114 			 * Unexpected disconnection! Cleanup and exit. This
1115 			 * shouldn't cause any problems.
1116 			 */
1117 			printf("escintr: Unexpected disconnection\n");
1118 			printf("escintr: u %x s %d p %d f %x c %x\n",
1119 			       nexus->lun_unit, nexus->state,
1120 			       dev->sc_status & ESC_STAT_PHASE_MASK,
1121 			       nexus->flags, nexus->cbuf[0]);
1122 
1123 			nexus->xs->resid = dev->sc_len;
1124 
1125 			nexus->flags &= ~ESC_NF_UNIT_BUSY;
1126 			nexus->state = ESC_NS_FINISHED;
1127 			nexus->status = -3;
1128 
1129 			dev->sc_led(dev, 0);
1130 			break;
1131 		}
1132 
1133 		/*
1134 		 * If we have disconnected units, we MUST enable reselection
1135 		 * within 250ms.
1136 		 */
1137 		if (dev->sc_units_disconnected &&
1138 		    !(dev->sc_flags & ESC_ACTIVE))
1139 			*rp->esc_command = ESC_CMD_ENABLE_RESEL;
1140 
1141 		splx(s);
1142 
1143 		/* Select the first pre-initialized nexus we find. */
1144 		for(i=0; i<8; i++)
1145 			if (dev->sc_nexus[i].flags & (ESC_NF_SELECT_ME | ESC_NF_RETRY_SELECT))
1146 				if (esc_select_unit(dev, i) == 2)
1147 					break;
1148 
1149 		/* We are done with this nexus! */
1150 		if (nexus->state == ESC_NS_FINISHED)
1151 			esc_scsidone(dev, nexus->xs, nexus->status);
1152 
1153 		return(1);
1154 	}
1155 
1156 	switch(nexus->state) {
1157 	case ESC_NS_SELECTED:
1158 		dev->sc_cur_nexus = nexus;
1159 		dev->sc_sel_nexus = 0;
1160 
1161 		nexus->flags &= ~ESC_NF_SELECT_ME;
1162 
1163 		/*
1164 		 * We have selected a unit. Setup chip, restore pointers and
1165 		 * light the led.
1166 		 */
1167 		*rp->esc_syncper = nexus->syncper;
1168 		*rp->esc_syncoff = nexus->syncoff;
1169 		*rp->esc_config3 = nexus->config3;
1170 
1171 		esc_restore_pointers(dev);
1172 
1173 		nexus->status	= 0xFF;
1174 		dev->sc_msg_in[0] = 0xFF;
1175 		dev->sc_msg_in_len= 0;
1176 
1177 		dev->sc_led(dev, 1);
1178 
1179 		break;
1180 
1181 	case ESC_NS_DATA_IN:
1182 	case ESC_NS_DATA_OUT:
1183 		/* We have transferred data. */
1184 		if (dev->sc_dma_len)
1185 			if (dev->sc_cur_link < dev->sc_max_link) {
1186 				/*
1187 				 * Clean up DMA and at the same time get how
1188 				 * many bytes that were NOT transferred.
1189 				 */
1190 			  left = dev->sc_setup_dma(dev, 0, 0, ESC_DMA_CLEAR);
1191 			  len  = dev->sc_dma_len;
1192 
1193 			  if (nexus->state == ESC_NS_DATA_IN) {
1194 			    /*
1195 			     * If we were bumping we may have had an odd length
1196 			     * which means that there may be bytes left in the
1197 			     * fifo. We also need to move the data from the
1198 			     * bump buffer to the actual memory.
1199 			     */
1200 			    if (dev->sc_dma_buf == dev->sc_bump_pa)
1201 			    {
1202 			      while((*rp->esc_fifo_flags&ESC_FIFO_COUNT_MASK)
1203 				    && left)
1204 				dev->sc_bump_va[len-(left--)] = *rp->esc_fifo;
1205 
1206 			      memcpy(dev->sc_buf, dev->sc_bump_va, len-left);
1207 			    }
1208 			  } else {
1209 			    /* Count any unsent bytes and flush them. */
1210 			    left+= *rp->esc_fifo_flags & ESC_FIFO_COUNT_MASK;
1211 			    *rp->esc_command = ESC_CMD_FLUSH_FIFO;
1212 			  }
1213 
1214 			  /*
1215 			   * Update pointers/length to reflect the transferred
1216 			   * data.
1217 			   */
1218 			  dev->sc_len -= len-left;
1219 			  dev->sc_buf += len-left;
1220 
1221 			  dev->sc_dma_buf = (char *)dev->sc_dma_buf + len-left;
1222 			  dev->sc_dma_len = left;
1223 
1224 			  dev->sc_dma_blk_ptr = (char *)dev->sc_dma_blk_ptr +
1225 				  len-left;
1226 			  dev->sc_dma_blk_len -= len-left;
1227 
1228 			  /*
1229 			   * If it was the end of a DMA block, we select the
1230 			   * next to begin with.
1231 			   */
1232 			  if (!dev->sc_dma_blk_len)
1233 			    dev->sc_cur_link++;
1234 			}
1235 		break;
1236 
1237 	case ESC_NS_STATUS:
1238 		/*
1239 		 * If we were not sensing, grab the status byte. If we were
1240 		 * sensing and we got a bad status, let the user know.
1241 		 */
1242 
1243 		status = *rp->esc_fifo;
1244 		msg = *rp->esc_fifo;
1245 
1246 		nexus->status = status;
1247 		if (status != 0)
1248 			nexus->status = -1;
1249 
1250 		/*
1251 		 * Preload the command complete message. Handled in
1252 		 * esc_postaction.
1253 		 */
1254 		dev->sc_msg_in[0] = msg;
1255 		dev->sc_msg_in_len = 1;
1256 		nexus->flags |= ESC_NF_HAS_MSG;
1257 		break;
1258 
1259 	default:
1260 		break;
1261 	}
1262 
1263 	return(0);
1264 }
1265 
1266 /*
1267  * Part three of the interrupt machine. Handle phase changes (and repeated
1268  * phase passes). We know that we have an active nexus here.
1269  */
1270 int
esc_postaction(struct esc_softc * dev,esc_regmap_p rp,struct nexus * nexus)1271 esc_postaction(struct esc_softc *dev, esc_regmap_p rp, struct nexus *nexus)
1272 {
1273 	int	i, len;
1274 	u_char	cmd;
1275 	short	offset, period;
1276 
1277 	cmd = 0;
1278 
1279 	switch(dev->sc_status & ESC_STAT_PHASE_MASK) {
1280 	case ESC_PHASE_DATA_OUT:
1281 	case ESC_PHASE_DATA_IN:
1282 		if ((dev->sc_status & ESC_STAT_PHASE_MASK) ==
1283 		    ESC_PHASE_DATA_OUT)
1284 			nexus->state = ESC_NS_DATA_OUT;
1285 		else
1286 			nexus->state = ESC_NS_DATA_IN;
1287 
1288 		/* Make DMA ready to accept new data. Load active pointers
1289 		 * from the DMA block. */
1290 		dev->sc_setup_dma(dev, 0, 0, ESC_DMA_CLEAR);
1291 		if (dev->sc_cur_link < dev->sc_max_link) {
1292 		  if (!dev->sc_dma_blk_len) {
1293 		    dev->sc_dma_blk_ptr = dev->sc_chain[dev->sc_cur_link].ptr;
1294 		    dev->sc_dma_blk_len = dev->sc_chain[dev->sc_cur_link].len;
1295 		    dev->sc_dma_blk_flg = dev->sc_chain[dev->sc_cur_link].flg;
1296 		  }
1297 
1298 		  /* We should use polled IO here. */
1299 		  if (dev->sc_dma_blk_flg == ESC_CHAIN_PRG) {
1300 			esc_ixfer(dev/*, nexus->xs->xs_control & XS_CTL_POLL*/);
1301 			dev->sc_cur_link++;
1302 			dev->sc_dma_len = 0;
1303 			break;
1304 		  }
1305 		  else if (dev->sc_dma_blk_flg == ESC_CHAIN_BUMP)
1306 			len = dev->sc_dma_blk_len;
1307 		  else
1308 			len = dev->sc_need_bump(dev,
1309 						(void *)dev->sc_dma_blk_ptr,
1310 						dev->sc_dma_blk_len);
1311 
1312 		  /*
1313 		   * If len != 0 we must bump the data, else we just DMA it
1314 		   * straight into memory.
1315 		   */
1316 		  if (len) {
1317 			dev->sc_dma_buf = dev->sc_bump_pa;
1318 			dev->sc_dma_len = len;
1319 
1320 			if (nexus->state == ESC_NS_DATA_OUT)
1321 			  memcpy(dev->sc_bump_va, dev->sc_buf, dev->sc_dma_len);
1322 		  } else {
1323 			dev->sc_dma_buf = dev->sc_dma_blk_ptr;
1324 			dev->sc_dma_len = dev->sc_dma_blk_len;
1325 		  }
1326 
1327 		  /* Load DMA with address and length of transfer. */
1328 		  dev->sc_setup_dma(dev, (void *)dev->sc_dma_buf,
1329 		  		    dev->sc_dma_len,
1330 				    ((nexus->state == ESC_NS_DATA_OUT) ?
1331 				     ESC_DMA_WRITE : ESC_DMA_READ));
1332 
1333 		  printf("Using DMA !!!!\n");
1334 		  cmd = ESC_CMD_TRANSFER_INFO | ESC_CMD_DMA;
1335 		} else {
1336 			/*
1337 			 * Hmmm, the unit wants more info than we have or has
1338 			 * more than we want. Let the chip handle that.
1339 			 */
1340 
1341 			*rp->esc_tc_low = 0;
1342 			*rp->esc_tc_mid = 1;
1343 			*rp->esc_tc_high = 0;
1344 			cmd = ESC_CMD_TRANSFER_PAD;
1345 		}
1346 		break;
1347 
1348 	case ESC_PHASE_COMMAND:
1349 		/* The scsi unit wants the command, send it. */
1350 		nexus->state = ESC_NS_SVC;
1351 
1352 		*rp->esc_command = ESC_CMD_FLUSH_FIFO;
1353 		for(i=0; i<5; i++);
1354 
1355 		for(i=0; i<nexus->clen; i++)
1356 			*rp->esc_fifo = nexus->cbuf[i];
1357 		cmd = ESC_CMD_TRANSFER_INFO;
1358 		break;
1359 
1360 	case ESC_PHASE_STATUS:
1361 		/*
1362 		 * We've got status phase. Request status and command
1363 		 * complete message.
1364 		 */
1365 		nexus->state = ESC_NS_STATUS;
1366 		cmd = ESC_CMD_COMMAND_COMPLETE;
1367 		break;
1368 
1369 	case ESC_PHASE_MESSAGE_OUT:
1370 		/*
1371 		 * Either the scsi unit wants us to send a message or we have
1372 		 * asked for it by setting the ATN bit.
1373 		 */
1374 		nexus->state = ESC_NS_MSG_OUT;
1375 
1376 		*rp->esc_command = ESC_CMD_FLUSH_FIFO;
1377 
1378 		if (nexus->flags & ESC_NF_DO_SDTR) {
1379 			/* Send a Synchronous Data Transfer Request. */
1380 
1381 			esc_build_sdtrm(dev, nexus->period, nexus->offset);
1382 			nexus->flags |= ESC_NF_SDTR_SENT;
1383 			nexus->flags &= ~ESC_NF_DO_SDTR;
1384 		} else if (nexus->flags & ESC_NF_RESET) {
1385 			/* Send a reset scsi unit message. */
1386 
1387 			dev->sc_msg_out[0] = 0x0C;
1388 			dev->sc_msg_out_len = 1;
1389 			nexus->state = ESC_NS_RESET;
1390 			nexus->flags &= ~ESC_NF_RESET;
1391 		} else if (dev->sc_msg_out_len == 0) {
1392 			/* Don't know what to send so we send a NOP message. */
1393 
1394 			dev->sc_msg_out[0] = 0x08;
1395 			dev->sc_msg_out_len = 1;
1396 		}
1397 
1398 		cmd = ESC_CMD_TRANSFER_INFO;
1399 
1400 		for(i=0; i<dev->sc_msg_out_len; i++)
1401 			*rp->esc_fifo = dev->sc_msg_out[i];
1402 		dev->sc_msg_out_len = 0;
1403 
1404 		break;
1405 
1406 	case ESC_PHASE_MESSAGE_IN:
1407 		/* Receive a message from the scsi unit. */
1408 		nexus->state = ESC_NS_MSG_IN;
1409 
1410 		while(!(nexus->flags & ESC_NF_HAS_MSG)) {
1411 			*rp->esc_command = ESC_CMD_TRANSFER_INFO;
1412 			esciwait(dev);
1413 
1414 			dev->sc_msg_in[dev->sc_msg_in_len++] = *rp->esc_fifo;
1415 
1416 			/* Check if we got all the bytes in the message. */
1417 			if (dev->sc_msg_in[0] >= 0x80)       ;
1418 			else if (dev->sc_msg_in[0] >= 0x30)  ;
1419 			else if (((dev->sc_msg_in[0] >= 0x20) &&
1420 				  (dev->sc_msg_in_len == 2)) ||
1421 				 ((dev->sc_msg_in[0] != 0x01) &&
1422 				  (dev->sc_msg_in_len == 1))) {
1423 				nexus->flags |= ESC_NF_HAS_MSG;
1424 				break;
1425 			} else {
1426 			  if (dev->sc_msg_in_len >= 2)
1427 			    if ((dev->sc_msg_in[1]+2) == dev->sc_msg_in_len) {
1428 				nexus->flags |= ESC_NF_HAS_MSG;
1429 				break;
1430 			    }
1431 			}
1432 
1433 			*rp->esc_command = ESC_CMD_MESSAGE_ACCEPTED;
1434 			esciwait(dev);
1435 
1436 			if ((dev->sc_status & ESC_STAT_PHASE_MASK) !=
1437 			    ESC_PHASE_MESSAGE_IN)
1438 				break;
1439 		}
1440 
1441 		cmd = ESC_CMD_MESSAGE_ACCEPTED;
1442 		if (nexus->flags & ESC_NF_HAS_MSG) {
1443 			/* We have a message. Decode it. */
1444 
1445 			switch(dev->sc_msg_in[0]) {
1446 			case 0x00:	/* COMMAND COMPLETE */
1447 				nexus->state = ESC_NS_DONE;
1448 				break;
1449 			case 0x04:	/* DISCONNECT */
1450 				nexus->state = ESC_NS_DISCONNECTING;
1451 				break;
1452 			case 0x02:	/* SAVE DATA POINTER */
1453 				esc_save_pointers(dev);
1454 				break;
1455 			case 0x03:	/* RESTORE DATA POINTERS */
1456 				esc_restore_pointers(dev);
1457 				break;
1458 			case 0x07:	/* MESSAGE REJECT */
1459 				/*
1460 				 * If we had sent a SDTR and we got a message
1461 				 * reject, the scsi docs say that we must go
1462 				 * to async transfer.
1463 				 */
1464 				if (nexus->flags & ESC_NF_SDTR_SENT) {
1465 					nexus->flags &= ~ESC_NF_SDTR_SENT;
1466 
1467 					nexus->config3 &= ~ESC_CFG3_FASTSCSI;
1468 					nexus->syncper = 5;
1469 					nexus->syncoff = 0;
1470 
1471 					*rp->esc_syncper = nexus->syncper;
1472 					*rp->esc_syncoff = nexus->syncoff;
1473 					*rp->esc_config3 = nexus->config3;
1474 				} else
1475 				/*
1476 				 * Something was rejected but we don't know
1477 				 * what! PANIC!
1478 				 */
1479 				  panic("escintr: Unknown message rejected!");
1480 				break;
1481 			case 0x08:	/* MO OPERATION */
1482 				break;
1483 			case 0x01:	/* EXTENDED MESSAGE */
1484 				switch(dev->sc_msg_in[2]) {
1485 				case 0x01:/* SYNC. DATA TRANSFER REQUEST */
1486 					/* Decode the SDTR message. */
1487 					period = 4*dev->sc_msg_in[3];
1488 					offset = dev->sc_msg_in[4];
1489 
1490 					/*
1491 					 * Make sure that the specs are within
1492 					 * chip limits. Note that if we
1493 					 * initiated the negotiation the specs
1494 					 * WILL be within chip limits. If it
1495 					 * was the scsi unit that initiated
1496 					 * the negotiation, the specs may be
1497 					 * to high.
1498 					 */
1499 					if (offset > 16)
1500 						offset = 16;
1501 					if ((period < 200) &&
1502 					    (dev->sc_clock_freq <= 25))
1503 						period = 200;
1504 
1505 					if (offset == 0)
1506 					       period = 5*dev->sc_clock_period;
1507 
1508 					nexus->syncper = period/
1509 							  dev->sc_clock_period;
1510 					nexus->syncoff = offset;
1511 
1512 					if (period < 200)
1513 					  nexus->config3 |= ESC_CFG3_FASTSCSI;
1514 					else
1515 					  nexus->config3 &=~ESC_CFG3_FASTSCSI;
1516 
1517 					nexus->flags |= ESC_NF_SYNC_TESTED;
1518 
1519 					*rp->esc_syncper = nexus->syncper;
1520 					*rp->esc_syncoff = nexus->syncoff;
1521 					*rp->esc_config3 = nexus->config3;
1522 
1523 					/*
1524 					 * Hmmm, it seems that the scsi unit
1525 					 * initiated sync negotiation, so lets
1526 					 * reply according to scsi-2 standard.
1527 					 */
1528 					if (!(nexus->flags& ESC_NF_SDTR_SENT))
1529 					{
1530 					  if ((dev->sc_config_flags &
1531 					       ESC_NO_SYNCH) ||
1532 					      (dev->sc_config_flags &
1533 					       ESC_NO_DMA) ||
1534 					      esc_inhibit_sync[
1535 							nexus->lun_unit & 7]) {
1536 					          period = 200;
1537 					          offset = 0;
1538 					  }
1539 
1540 					  nexus->offset = offset;
1541 					  nexus->period = period;
1542 					  nexus->flags |= ESC_NF_DO_SDTR;
1543 					  *rp->esc_command = ESC_CMD_SET_ATN;
1544 					}
1545 
1546 					nexus->flags &= ~ESC_NF_SDTR_SENT;
1547 					break;
1548 
1549 				case 0x00: /* MODIFY DATA POINTERS */
1550 				case 0x02: /* EXTENDED IDENTIFY (SCSI-1) */
1551 				case 0x03: /* WIDE DATA TRANSFER REQUEST */
1552 			        default:
1553 					/* Reject any unhandled messages. */
1554 
1555 					dev->sc_msg_out[0] = 0x07;
1556 					dev->sc_msg_out_len = 1;
1557 					*rp->esc_command = ESC_CMD_SET_ATN;
1558 					cmd = ESC_CMD_MESSAGE_ACCEPTED;
1559 					break;
1560 				}
1561 				break;
1562 
1563 			default:
1564 				/* Reject any unhandled messages. */
1565 
1566 				dev->sc_msg_out[0] = 0x07;
1567 				dev->sc_msg_out_len = 1;
1568 				*rp->esc_command = ESC_CMD_SET_ATN;
1569 				cmd = ESC_CMD_MESSAGE_ACCEPTED;
1570 				break;
1571 			}
1572 			nexus->flags &= ~ESC_NF_HAS_MSG;
1573 			dev->sc_msg_in_len = 0;
1574 		}
1575 		break;
1576 	default:
1577 		printf("ESCINTR: UNKNOWN PHASE! phase: %d\n",
1578 		       dev->sc_status & ESC_STAT_PHASE_MASK);
1579 		dev->sc_led(dev, 0);
1580 		esc_scsidone(dev, nexus->xs, -4);
1581 
1582 		return(-1);
1583 	}
1584 
1585 	if (cmd)
1586 		*rp->esc_command = cmd;
1587 
1588 	return(0);
1589 }
1590 
1591 /*
1592  * Stub for interrupt machine.
1593  */
1594 void
escintr(struct esc_softc * dev)1595 escintr(struct esc_softc *dev)
1596 {
1597 	esc_regmap_p	 rp;
1598 	struct nexus	*nexus;
1599 
1600 	rp = dev->sc_esc;
1601 
1602 	if (!esc_pretests(dev, rp)) {
1603 
1604 		nexus = dev->sc_cur_nexus;
1605 		if (nexus == NULL)
1606 			nexus = dev->sc_sel_nexus;
1607 
1608 		if (nexus)
1609 			if (!esc_midaction(dev, rp, nexus))
1610 				esc_postaction(dev, rp, nexus);
1611 	}
1612 }
1613 
1614 /*
1615  * escicmd is used to perform IO when we can't use interrupts. escicmd
1616  * emulates the normal environment by waiting for the chip and calling
1617  * escintr.
1618  */
1619 void
escicmd(struct esc_softc * dev,struct esc_pending * pendp)1620 escicmd(struct esc_softc *dev, struct esc_pending *pendp)
1621 {
1622 	struct nexus	*nexus;
1623 
1624 	nexus = &dev->sc_nexus[pendp->xs->xs_periph->periph_target];
1625 
1626 	if (!escselect(dev, pendp, (char *)pendp->xs->cmd, pendp->xs->cmdlen,
1627 			(char *)pendp->xs->data, pendp->xs->datalen,
1628 			ESC_SELECT_I))
1629 		panic("escicmd: Couldn't select unit");
1630 
1631 	while(nexus->state != ESC_NS_FINISHED) {
1632 		esciwait(dev);
1633 		escintr(dev);
1634 	}
1635 
1636 	nexus->flags &= ~ESC_NF_SYNC_TESTED;
1637 }
1638