xref: /linux/drivers/scsi/esp_scsi.c (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
1 /* esp_scsi.c: ESP SCSI driver.
2  *
3  * Copyright (C) 2007 David S. Miller (davem@davemloft.net)
4  */
5 
6 #include <linux/kernel.h>
7 #include <linux/types.h>
8 #include <linux/slab.h>
9 #include <linux/delay.h>
10 #include <linux/list.h>
11 #include <linux/completion.h>
12 #include <linux/kallsyms.h>
13 #include <linux/module.h>
14 #include <linux/moduleparam.h>
15 #include <linux/init.h>
16 #include <linux/irqreturn.h>
17 
18 #include <asm/irq.h>
19 #include <asm/io.h>
20 #include <asm/dma.h>
21 
22 #include <scsi/scsi.h>
23 #include <scsi/scsi_host.h>
24 #include <scsi/scsi_cmnd.h>
25 #include <scsi/scsi_device.h>
26 #include <scsi/scsi_tcq.h>
27 #include <scsi/scsi_dbg.h>
28 #include <scsi/scsi_transport_spi.h>
29 
30 #include "esp_scsi.h"
31 
32 #define DRV_MODULE_NAME		"esp"
33 #define PFX DRV_MODULE_NAME	": "
34 #define DRV_VERSION		"2.000"
35 #define DRV_MODULE_RELDATE	"April 19, 2007"
36 
37 /* SCSI bus reset settle time in seconds.  */
38 static int esp_bus_reset_settle = 3;
39 
40 static u32 esp_debug;
41 #define ESP_DEBUG_INTR		0x00000001
42 #define ESP_DEBUG_SCSICMD	0x00000002
43 #define ESP_DEBUG_RESET		0x00000004
44 #define ESP_DEBUG_MSGIN		0x00000008
45 #define ESP_DEBUG_MSGOUT	0x00000010
46 #define ESP_DEBUG_CMDDONE	0x00000020
47 #define ESP_DEBUG_DISCONNECT	0x00000040
48 #define ESP_DEBUG_DATASTART	0x00000080
49 #define ESP_DEBUG_DATADONE	0x00000100
50 #define ESP_DEBUG_RECONNECT	0x00000200
51 #define ESP_DEBUG_AUTOSENSE	0x00000400
52 
53 #define esp_log_intr(f, a...) \
54 do {	if (esp_debug & ESP_DEBUG_INTR) \
55 		printk(f, ## a); \
56 } while (0)
57 
58 #define esp_log_reset(f, a...) \
59 do {	if (esp_debug & ESP_DEBUG_RESET) \
60 		printk(f, ## a); \
61 } while (0)
62 
63 #define esp_log_msgin(f, a...) \
64 do {	if (esp_debug & ESP_DEBUG_MSGIN) \
65 		printk(f, ## a); \
66 } while (0)
67 
68 #define esp_log_msgout(f, a...) \
69 do {	if (esp_debug & ESP_DEBUG_MSGOUT) \
70 		printk(f, ## a); \
71 } while (0)
72 
73 #define esp_log_cmddone(f, a...) \
74 do {	if (esp_debug & ESP_DEBUG_CMDDONE) \
75 		printk(f, ## a); \
76 } while (0)
77 
78 #define esp_log_disconnect(f, a...) \
79 do {	if (esp_debug & ESP_DEBUG_DISCONNECT) \
80 		printk(f, ## a); \
81 } while (0)
82 
83 #define esp_log_datastart(f, a...) \
84 do {	if (esp_debug & ESP_DEBUG_DATASTART) \
85 		printk(f, ## a); \
86 } while (0)
87 
88 #define esp_log_datadone(f, a...) \
89 do {	if (esp_debug & ESP_DEBUG_DATADONE) \
90 		printk(f, ## a); \
91 } while (0)
92 
93 #define esp_log_reconnect(f, a...) \
94 do {	if (esp_debug & ESP_DEBUG_RECONNECT) \
95 		printk(f, ## a); \
96 } while (0)
97 
98 #define esp_log_autosense(f, a...) \
99 do {	if (esp_debug & ESP_DEBUG_AUTOSENSE) \
100 		printk(f, ## a); \
101 } while (0)
102 
103 #define esp_read8(REG)		esp->ops->esp_read8(esp, REG)
104 #define esp_write8(VAL,REG)	esp->ops->esp_write8(esp, VAL, REG)
105 
106 static void esp_log_fill_regs(struct esp *esp,
107 			      struct esp_event_ent *p)
108 {
109 	p->sreg = esp->sreg;
110 	p->seqreg = esp->seqreg;
111 	p->sreg2 = esp->sreg2;
112 	p->ireg = esp->ireg;
113 	p->select_state = esp->select_state;
114 	p->event = esp->event;
115 }
116 
117 void scsi_esp_cmd(struct esp *esp, u8 val)
118 {
119 	struct esp_event_ent *p;
120 	int idx = esp->esp_event_cur;
121 
122 	p = &esp->esp_event_log[idx];
123 	p->type = ESP_EVENT_TYPE_CMD;
124 	p->val = val;
125 	esp_log_fill_regs(esp, p);
126 
127 	esp->esp_event_cur = (idx + 1) & (ESP_EVENT_LOG_SZ - 1);
128 
129 	esp_write8(val, ESP_CMD);
130 }
131 EXPORT_SYMBOL(scsi_esp_cmd);
132 
133 static void esp_event(struct esp *esp, u8 val)
134 {
135 	struct esp_event_ent *p;
136 	int idx = esp->esp_event_cur;
137 
138 	p = &esp->esp_event_log[idx];
139 	p->type = ESP_EVENT_TYPE_EVENT;
140 	p->val = val;
141 	esp_log_fill_regs(esp, p);
142 
143 	esp->esp_event_cur = (idx + 1) & (ESP_EVENT_LOG_SZ - 1);
144 
145 	esp->event = val;
146 }
147 
148 static void esp_dump_cmd_log(struct esp *esp)
149 {
150 	int idx = esp->esp_event_cur;
151 	int stop = idx;
152 
153 	printk(KERN_INFO PFX "esp%d: Dumping command log\n",
154 	       esp->host->unique_id);
155 	do {
156 		struct esp_event_ent *p = &esp->esp_event_log[idx];
157 
158 		printk(KERN_INFO PFX "esp%d: ent[%d] %s ",
159 		       esp->host->unique_id, idx,
160 		       p->type == ESP_EVENT_TYPE_CMD ? "CMD" : "EVENT");
161 
162 		printk("val[%02x] sreg[%02x] seqreg[%02x] "
163 		       "sreg2[%02x] ireg[%02x] ss[%02x] event[%02x]\n",
164 		       p->val, p->sreg, p->seqreg,
165 		       p->sreg2, p->ireg, p->select_state, p->event);
166 
167 		idx = (idx + 1) & (ESP_EVENT_LOG_SZ - 1);
168 	} while (idx != stop);
169 }
170 
171 static void esp_flush_fifo(struct esp *esp)
172 {
173 	scsi_esp_cmd(esp, ESP_CMD_FLUSH);
174 	if (esp->rev == ESP236) {
175 		int lim = 1000;
176 
177 		while (esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES) {
178 			if (--lim == 0) {
179 				printk(KERN_ALERT PFX "esp%d: ESP_FF_BYTES "
180 				       "will not clear!\n",
181 				       esp->host->unique_id);
182 				break;
183 			}
184 			udelay(1);
185 		}
186 	}
187 }
188 
189 static void hme_read_fifo(struct esp *esp)
190 {
191 	int fcnt = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;
192 	int idx = 0;
193 
194 	while (fcnt--) {
195 		esp->fifo[idx++] = esp_read8(ESP_FDATA);
196 		esp->fifo[idx++] = esp_read8(ESP_FDATA);
197 	}
198 	if (esp->sreg2 & ESP_STAT2_F1BYTE) {
199 		esp_write8(0, ESP_FDATA);
200 		esp->fifo[idx++] = esp_read8(ESP_FDATA);
201 		scsi_esp_cmd(esp, ESP_CMD_FLUSH);
202 	}
203 	esp->fifo_cnt = idx;
204 }
205 
206 static void esp_set_all_config3(struct esp *esp, u8 val)
207 {
208 	int i;
209 
210 	for (i = 0; i < ESP_MAX_TARGET; i++)
211 		esp->target[i].esp_config3 = val;
212 }
213 
214 /* Reset the ESP chip, _not_ the SCSI bus. */
215 static void esp_reset_esp(struct esp *esp)
216 {
217 	u8 family_code, version;
218 
219 	/* Now reset the ESP chip */
220 	scsi_esp_cmd(esp, ESP_CMD_RC);
221 	scsi_esp_cmd(esp, ESP_CMD_NULL | ESP_CMD_DMA);
222 	if (esp->rev == FAST)
223 		esp_write8(ESP_CONFIG2_FENAB, ESP_CFG2);
224 	scsi_esp_cmd(esp, ESP_CMD_NULL | ESP_CMD_DMA);
225 
226 	/* This is the only point at which it is reliable to read
227 	 * the ID-code for a fast ESP chip variants.
228 	 */
229 	esp->max_period = ((35 * esp->ccycle) / 1000);
230 	if (esp->rev == FAST) {
231 		version = esp_read8(ESP_UID);
232 		family_code = (version & 0xf8) >> 3;
233 		if (family_code == 0x02)
234 			esp->rev = FAS236;
235 		else if (family_code == 0x0a)
236 			esp->rev = FASHME; /* Version is usually '5'. */
237 		else
238 			esp->rev = FAS100A;
239 		esp->min_period = ((4 * esp->ccycle) / 1000);
240 	} else {
241 		esp->min_period = ((5 * esp->ccycle) / 1000);
242 	}
243 	esp->max_period = (esp->max_period + 3)>>2;
244 	esp->min_period = (esp->min_period + 3)>>2;
245 
246 	esp_write8(esp->config1, ESP_CFG1);
247 	switch (esp->rev) {
248 	case ESP100:
249 		/* nothing to do */
250 		break;
251 
252 	case ESP100A:
253 		esp_write8(esp->config2, ESP_CFG2);
254 		break;
255 
256 	case ESP236:
257 		/* Slow 236 */
258 		esp_write8(esp->config2, ESP_CFG2);
259 		esp->prev_cfg3 = esp->target[0].esp_config3;
260 		esp_write8(esp->prev_cfg3, ESP_CFG3);
261 		break;
262 
263 	case FASHME:
264 		esp->config2 |= (ESP_CONFIG2_HME32 | ESP_CONFIG2_HMEFENAB);
265 		/* fallthrough... */
266 
267 	case FAS236:
268 		/* Fast 236 or HME */
269 		esp_write8(esp->config2, ESP_CFG2);
270 		if (esp->rev == FASHME) {
271 			u8 cfg3 = esp->target[0].esp_config3;
272 
273 			cfg3 |= ESP_CONFIG3_FCLOCK | ESP_CONFIG3_OBPUSH;
274 			if (esp->scsi_id >= 8)
275 				cfg3 |= ESP_CONFIG3_IDBIT3;
276 			esp_set_all_config3(esp, cfg3);
277 		} else {
278 			u32 cfg3 = esp->target[0].esp_config3;
279 
280 			cfg3 |= ESP_CONFIG3_FCLK;
281 			esp_set_all_config3(esp, cfg3);
282 		}
283 		esp->prev_cfg3 = esp->target[0].esp_config3;
284 		esp_write8(esp->prev_cfg3, ESP_CFG3);
285 		if (esp->rev == FASHME) {
286 			esp->radelay = 80;
287 		} else {
288 			if (esp->flags & ESP_FLAG_DIFFERENTIAL)
289 				esp->radelay = 0;
290 			else
291 				esp->radelay = 96;
292 		}
293 		break;
294 
295 	case FAS100A:
296 		/* Fast 100a */
297 		esp_write8(esp->config2, ESP_CFG2);
298 		esp_set_all_config3(esp,
299 				    (esp->target[0].esp_config3 |
300 				     ESP_CONFIG3_FCLOCK));
301 		esp->prev_cfg3 = esp->target[0].esp_config3;
302 		esp_write8(esp->prev_cfg3, ESP_CFG3);
303 		esp->radelay = 32;
304 		break;
305 
306 	default:
307 		break;
308 	}
309 
310 	/* Reload the configuration registers */
311 	esp_write8(esp->cfact, ESP_CFACT);
312 
313 	esp->prev_stp = 0;
314 	esp_write8(esp->prev_stp, ESP_STP);
315 
316 	esp->prev_soff = 0;
317 	esp_write8(esp->prev_soff, ESP_SOFF);
318 
319 	esp_write8(esp->neg_defp, ESP_TIMEO);
320 
321 	/* Eat any bitrot in the chip */
322 	esp_read8(ESP_INTRPT);
323 	udelay(100);
324 }
325 
326 static void esp_map_dma(struct esp *esp, struct scsi_cmnd *cmd)
327 {
328 	struct esp_cmd_priv *spriv = ESP_CMD_PRIV(cmd);
329 	struct scatterlist *sg = scsi_sglist(cmd);
330 	int dir = cmd->sc_data_direction;
331 	int total, i;
332 
333 	if (dir == DMA_NONE)
334 		return;
335 
336 	spriv->u.num_sg = esp->ops->map_sg(esp, sg, scsi_sg_count(cmd), dir);
337 	spriv->cur_residue = sg_dma_len(sg);
338 	spriv->cur_sg = sg;
339 
340 	total = 0;
341 	for (i = 0; i < spriv->u.num_sg; i++)
342 		total += sg_dma_len(&sg[i]);
343 	spriv->tot_residue = total;
344 }
345 
346 static dma_addr_t esp_cur_dma_addr(struct esp_cmd_entry *ent,
347 				   struct scsi_cmnd *cmd)
348 {
349 	struct esp_cmd_priv *p = ESP_CMD_PRIV(cmd);
350 
351 	if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
352 		return ent->sense_dma +
353 			(ent->sense_ptr - cmd->sense_buffer);
354 	}
355 
356 	return sg_dma_address(p->cur_sg) +
357 		(sg_dma_len(p->cur_sg) -
358 		 p->cur_residue);
359 }
360 
361 static unsigned int esp_cur_dma_len(struct esp_cmd_entry *ent,
362 				    struct scsi_cmnd *cmd)
363 {
364 	struct esp_cmd_priv *p = ESP_CMD_PRIV(cmd);
365 
366 	if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
367 		return SCSI_SENSE_BUFFERSIZE -
368 			(ent->sense_ptr - cmd->sense_buffer);
369 	}
370 	return p->cur_residue;
371 }
372 
373 static void esp_advance_dma(struct esp *esp, struct esp_cmd_entry *ent,
374 			    struct scsi_cmnd *cmd, unsigned int len)
375 {
376 	struct esp_cmd_priv *p = ESP_CMD_PRIV(cmd);
377 
378 	if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
379 		ent->sense_ptr += len;
380 		return;
381 	}
382 
383 	p->cur_residue -= len;
384 	p->tot_residue -= len;
385 	if (p->cur_residue < 0 || p->tot_residue < 0) {
386 		printk(KERN_ERR PFX "esp%d: Data transfer overflow.\n",
387 		       esp->host->unique_id);
388 		printk(KERN_ERR PFX "esp%d: cur_residue[%d] tot_residue[%d] "
389 		       "len[%u]\n",
390 		       esp->host->unique_id,
391 		       p->cur_residue, p->tot_residue, len);
392 		p->cur_residue = 0;
393 		p->tot_residue = 0;
394 	}
395 	if (!p->cur_residue && p->tot_residue) {
396 		p->cur_sg++;
397 		p->cur_residue = sg_dma_len(p->cur_sg);
398 	}
399 }
400 
401 static void esp_unmap_dma(struct esp *esp, struct scsi_cmnd *cmd)
402 {
403 	struct esp_cmd_priv *spriv = ESP_CMD_PRIV(cmd);
404 	int dir = cmd->sc_data_direction;
405 
406 	if (dir == DMA_NONE)
407 		return;
408 
409 	esp->ops->unmap_sg(esp, scsi_sglist(cmd), spriv->u.num_sg, dir);
410 }
411 
412 static void esp_save_pointers(struct esp *esp, struct esp_cmd_entry *ent)
413 {
414 	struct scsi_cmnd *cmd = ent->cmd;
415 	struct esp_cmd_priv *spriv = ESP_CMD_PRIV(cmd);
416 
417 	if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
418 		ent->saved_sense_ptr = ent->sense_ptr;
419 		return;
420 	}
421 	ent->saved_cur_residue = spriv->cur_residue;
422 	ent->saved_cur_sg = spriv->cur_sg;
423 	ent->saved_tot_residue = spriv->tot_residue;
424 }
425 
426 static void esp_restore_pointers(struct esp *esp, struct esp_cmd_entry *ent)
427 {
428 	struct scsi_cmnd *cmd = ent->cmd;
429 	struct esp_cmd_priv *spriv = ESP_CMD_PRIV(cmd);
430 
431 	if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
432 		ent->sense_ptr = ent->saved_sense_ptr;
433 		return;
434 	}
435 	spriv->cur_residue = ent->saved_cur_residue;
436 	spriv->cur_sg = ent->saved_cur_sg;
437 	spriv->tot_residue = ent->saved_tot_residue;
438 }
439 
440 static void esp_check_command_len(struct esp *esp, struct scsi_cmnd *cmd)
441 {
442 	if (cmd->cmd_len == 6 ||
443 	    cmd->cmd_len == 10 ||
444 	    cmd->cmd_len == 12) {
445 		esp->flags &= ~ESP_FLAG_DOING_SLOWCMD;
446 	} else {
447 		esp->flags |= ESP_FLAG_DOING_SLOWCMD;
448 	}
449 }
450 
451 static void esp_write_tgt_config3(struct esp *esp, int tgt)
452 {
453 	if (esp->rev > ESP100A) {
454 		u8 val = esp->target[tgt].esp_config3;
455 
456 		if (val != esp->prev_cfg3) {
457 			esp->prev_cfg3 = val;
458 			esp_write8(val, ESP_CFG3);
459 		}
460 	}
461 }
462 
463 static void esp_write_tgt_sync(struct esp *esp, int tgt)
464 {
465 	u8 off = esp->target[tgt].esp_offset;
466 	u8 per = esp->target[tgt].esp_period;
467 
468 	if (off != esp->prev_soff) {
469 		esp->prev_soff = off;
470 		esp_write8(off, ESP_SOFF);
471 	}
472 	if (per != esp->prev_stp) {
473 		esp->prev_stp = per;
474 		esp_write8(per, ESP_STP);
475 	}
476 }
477 
478 static u32 esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len)
479 {
480 	if (esp->rev == FASHME) {
481 		/* Arbitrary segment boundaries, 24-bit counts.  */
482 		if (dma_len > (1U << 24))
483 			dma_len = (1U << 24);
484 	} else {
485 		u32 base, end;
486 
487 		/* ESP chip limits other variants by 16-bits of transfer
488 		 * count.  Actually on FAS100A and FAS236 we could get
489 		 * 24-bits of transfer count by enabling ESP_CONFIG2_FENAB
490 		 * in the ESP_CFG2 register but that causes other unwanted
491 		 * changes so we don't use it currently.
492 		 */
493 		if (dma_len > (1U << 16))
494 			dma_len = (1U << 16);
495 
496 		/* All of the DMA variants hooked up to these chips
497 		 * cannot handle crossing a 24-bit address boundary.
498 		 */
499 		base = dma_addr & ((1U << 24) - 1U);
500 		end = base + dma_len;
501 		if (end > (1U << 24))
502 			end = (1U <<24);
503 		dma_len = end - base;
504 	}
505 	return dma_len;
506 }
507 
508 static int esp_need_to_nego_wide(struct esp_target_data *tp)
509 {
510 	struct scsi_target *target = tp->starget;
511 
512 	return spi_width(target) != tp->nego_goal_width;
513 }
514 
515 static int esp_need_to_nego_sync(struct esp_target_data *tp)
516 {
517 	struct scsi_target *target = tp->starget;
518 
519 	/* When offset is zero, period is "don't care".  */
520 	if (!spi_offset(target) && !tp->nego_goal_offset)
521 		return 0;
522 
523 	if (spi_offset(target) == tp->nego_goal_offset &&
524 	    spi_period(target) == tp->nego_goal_period)
525 		return 0;
526 
527 	return 1;
528 }
529 
530 static int esp_alloc_lun_tag(struct esp_cmd_entry *ent,
531 			     struct esp_lun_data *lp)
532 {
533 	if (!ent->tag[0]) {
534 		/* Non-tagged, slot already taken?  */
535 		if (lp->non_tagged_cmd)
536 			return -EBUSY;
537 
538 		if (lp->hold) {
539 			/* We are being held by active tagged
540 			 * commands.
541 			 */
542 			if (lp->num_tagged)
543 				return -EBUSY;
544 
545 			/* Tagged commands completed, we can unplug
546 			 * the queue and run this untagged command.
547 			 */
548 			lp->hold = 0;
549 		} else if (lp->num_tagged) {
550 			/* Plug the queue until num_tagged decreases
551 			 * to zero in esp_free_lun_tag.
552 			 */
553 			lp->hold = 1;
554 			return -EBUSY;
555 		}
556 
557 		lp->non_tagged_cmd = ent;
558 		return 0;
559 	} else {
560 		/* Tagged command, see if blocked by a
561 		 * non-tagged one.
562 		 */
563 		if (lp->non_tagged_cmd || lp->hold)
564 			return -EBUSY;
565 	}
566 
567 	BUG_ON(lp->tagged_cmds[ent->tag[1]]);
568 
569 	lp->tagged_cmds[ent->tag[1]] = ent;
570 	lp->num_tagged++;
571 
572 	return 0;
573 }
574 
575 static void esp_free_lun_tag(struct esp_cmd_entry *ent,
576 			     struct esp_lun_data *lp)
577 {
578 	if (ent->tag[0]) {
579 		BUG_ON(lp->tagged_cmds[ent->tag[1]] != ent);
580 		lp->tagged_cmds[ent->tag[1]] = NULL;
581 		lp->num_tagged--;
582 	} else {
583 		BUG_ON(lp->non_tagged_cmd != ent);
584 		lp->non_tagged_cmd = NULL;
585 	}
586 }
587 
588 /* When a contingent allegiance conditon is created, we force feed a
589  * REQUEST_SENSE command to the device to fetch the sense data.  I
590  * tried many other schemes, relying on the scsi error handling layer
591  * to send out the REQUEST_SENSE automatically, but this was difficult
592  * to get right especially in the presence of applications like smartd
593  * which use SG_IO to send out their own REQUEST_SENSE commands.
594  */
595 static void esp_autosense(struct esp *esp, struct esp_cmd_entry *ent)
596 {
597 	struct scsi_cmnd *cmd = ent->cmd;
598 	struct scsi_device *dev = cmd->device;
599 	int tgt, lun;
600 	u8 *p, val;
601 
602 	tgt = dev->id;
603 	lun = dev->lun;
604 
605 
606 	if (!ent->sense_ptr) {
607 		esp_log_autosense("esp%d: Doing auto-sense for "
608 				  "tgt[%d] lun[%d]\n",
609 				  esp->host->unique_id, tgt, lun);
610 
611 		ent->sense_ptr = cmd->sense_buffer;
612 		ent->sense_dma = esp->ops->map_single(esp,
613 						      ent->sense_ptr,
614 						      SCSI_SENSE_BUFFERSIZE,
615 						      DMA_FROM_DEVICE);
616 	}
617 	ent->saved_sense_ptr = ent->sense_ptr;
618 
619 	esp->active_cmd = ent;
620 
621 	p = esp->command_block;
622 	esp->msg_out_len = 0;
623 
624 	*p++ = IDENTIFY(0, lun);
625 	*p++ = REQUEST_SENSE;
626 	*p++ = ((dev->scsi_level <= SCSI_2) ?
627 		(lun << 5) : 0);
628 	*p++ = 0;
629 	*p++ = 0;
630 	*p++ = SCSI_SENSE_BUFFERSIZE;
631 	*p++ = 0;
632 
633 	esp->select_state = ESP_SELECT_BASIC;
634 
635 	val = tgt;
636 	if (esp->rev == FASHME)
637 		val |= ESP_BUSID_RESELID | ESP_BUSID_CTR32BIT;
638 	esp_write8(val, ESP_BUSID);
639 
640 	esp_write_tgt_sync(esp, tgt);
641 	esp_write_tgt_config3(esp, tgt);
642 
643 	val = (p - esp->command_block);
644 
645 	if (esp->rev == FASHME)
646 		scsi_esp_cmd(esp, ESP_CMD_FLUSH);
647 	esp->ops->send_dma_cmd(esp, esp->command_block_dma,
648 			       val, 16, 0, ESP_CMD_DMA | ESP_CMD_SELA);
649 }
650 
651 static struct esp_cmd_entry *find_and_prep_issuable_command(struct esp *esp)
652 {
653 	struct esp_cmd_entry *ent;
654 
655 	list_for_each_entry(ent, &esp->queued_cmds, list) {
656 		struct scsi_cmnd *cmd = ent->cmd;
657 		struct scsi_device *dev = cmd->device;
658 		struct esp_lun_data *lp = dev->hostdata;
659 
660 		if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
661 			ent->tag[0] = 0;
662 			ent->tag[1] = 0;
663 			return ent;
664 		}
665 
666 		if (!scsi_populate_tag_msg(cmd, &ent->tag[0])) {
667 			ent->tag[0] = 0;
668 			ent->tag[1] = 0;
669 		}
670 
671 		if (esp_alloc_lun_tag(ent, lp) < 0)
672 			continue;
673 
674 		return ent;
675 	}
676 
677 	return NULL;
678 }
679 
680 static void esp_maybe_execute_command(struct esp *esp)
681 {
682 	struct esp_target_data *tp;
683 	struct esp_lun_data *lp;
684 	struct scsi_device *dev;
685 	struct scsi_cmnd *cmd;
686 	struct esp_cmd_entry *ent;
687 	int tgt, lun, i;
688 	u32 val, start_cmd;
689 	u8 *p;
690 
691 	if (esp->active_cmd ||
692 	    (esp->flags & ESP_FLAG_RESETTING))
693 		return;
694 
695 	ent = find_and_prep_issuable_command(esp);
696 	if (!ent)
697 		return;
698 
699 	if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
700 		esp_autosense(esp, ent);
701 		return;
702 	}
703 
704 	cmd = ent->cmd;
705 	dev = cmd->device;
706 	tgt = dev->id;
707 	lun = dev->lun;
708 	tp = &esp->target[tgt];
709 	lp = dev->hostdata;
710 
711 	list_move(&ent->list, &esp->active_cmds);
712 
713 	esp->active_cmd = ent;
714 
715 	esp_map_dma(esp, cmd);
716 	esp_save_pointers(esp, ent);
717 
718 	esp_check_command_len(esp, cmd);
719 
720 	p = esp->command_block;
721 
722 	esp->msg_out_len = 0;
723 	if (tp->flags & ESP_TGT_CHECK_NEGO) {
724 		/* Need to negotiate.  If the target is broken
725 		 * go for synchronous transfers and non-wide.
726 		 */
727 		if (tp->flags & ESP_TGT_BROKEN) {
728 			tp->flags &= ~ESP_TGT_DISCONNECT;
729 			tp->nego_goal_period = 0;
730 			tp->nego_goal_offset = 0;
731 			tp->nego_goal_width = 0;
732 			tp->nego_goal_tags = 0;
733 		}
734 
735 		/* If the settings are not changing, skip this.  */
736 		if (spi_width(tp->starget) == tp->nego_goal_width &&
737 		    spi_period(tp->starget) == tp->nego_goal_period &&
738 		    spi_offset(tp->starget) == tp->nego_goal_offset) {
739 			tp->flags &= ~ESP_TGT_CHECK_NEGO;
740 			goto build_identify;
741 		}
742 
743 		if (esp->rev == FASHME && esp_need_to_nego_wide(tp)) {
744 			esp->msg_out_len =
745 				spi_populate_width_msg(&esp->msg_out[0],
746 						       (tp->nego_goal_width ?
747 							1 : 0));
748 			tp->flags |= ESP_TGT_NEGO_WIDE;
749 		} else if (esp_need_to_nego_sync(tp)) {
750 			esp->msg_out_len =
751 				spi_populate_sync_msg(&esp->msg_out[0],
752 						      tp->nego_goal_period,
753 						      tp->nego_goal_offset);
754 			tp->flags |= ESP_TGT_NEGO_SYNC;
755 		} else {
756 			tp->flags &= ~ESP_TGT_CHECK_NEGO;
757 		}
758 
759 		/* Process it like a slow command.  */
760 		if (tp->flags & (ESP_TGT_NEGO_WIDE | ESP_TGT_NEGO_SYNC))
761 			esp->flags |= ESP_FLAG_DOING_SLOWCMD;
762 	}
763 
764 build_identify:
765 	/* If we don't have a lun-data struct yet, we're probing
766 	 * so do not disconnect.  Also, do not disconnect unless
767 	 * we have a tag on this command.
768 	 */
769 	if (lp && (tp->flags & ESP_TGT_DISCONNECT) && ent->tag[0])
770 		*p++ = IDENTIFY(1, lun);
771 	else
772 		*p++ = IDENTIFY(0, lun);
773 
774 	if (ent->tag[0] && esp->rev == ESP100) {
775 		/* ESP100 lacks select w/atn3 command, use select
776 		 * and stop instead.
777 		 */
778 		esp->flags |= ESP_FLAG_DOING_SLOWCMD;
779 	}
780 
781 	if (!(esp->flags & ESP_FLAG_DOING_SLOWCMD)) {
782 		start_cmd = ESP_CMD_DMA | ESP_CMD_SELA;
783 		if (ent->tag[0]) {
784 			*p++ = ent->tag[0];
785 			*p++ = ent->tag[1];
786 
787 			start_cmd = ESP_CMD_DMA | ESP_CMD_SA3;
788 		}
789 
790 		for (i = 0; i < cmd->cmd_len; i++)
791 			*p++ = cmd->cmnd[i];
792 
793 		esp->select_state = ESP_SELECT_BASIC;
794 	} else {
795 		esp->cmd_bytes_left = cmd->cmd_len;
796 		esp->cmd_bytes_ptr = &cmd->cmnd[0];
797 
798 		if (ent->tag[0]) {
799 			for (i = esp->msg_out_len - 1;
800 			     i >= 0; i--)
801 				esp->msg_out[i + 2] = esp->msg_out[i];
802 			esp->msg_out[0] = ent->tag[0];
803 			esp->msg_out[1] = ent->tag[1];
804 			esp->msg_out_len += 2;
805 		}
806 
807 		start_cmd = ESP_CMD_DMA | ESP_CMD_SELAS;
808 		esp->select_state = ESP_SELECT_MSGOUT;
809 	}
810 	val = tgt;
811 	if (esp->rev == FASHME)
812 		val |= ESP_BUSID_RESELID | ESP_BUSID_CTR32BIT;
813 	esp_write8(val, ESP_BUSID);
814 
815 	esp_write_tgt_sync(esp, tgt);
816 	esp_write_tgt_config3(esp, tgt);
817 
818 	val = (p - esp->command_block);
819 
820 	if (esp_debug & ESP_DEBUG_SCSICMD) {
821 		printk("ESP: tgt[%d] lun[%d] scsi_cmd [ ", tgt, lun);
822 		for (i = 0; i < cmd->cmd_len; i++)
823 			printk("%02x ", cmd->cmnd[i]);
824 		printk("]\n");
825 	}
826 
827 	if (esp->rev == FASHME)
828 		scsi_esp_cmd(esp, ESP_CMD_FLUSH);
829 	esp->ops->send_dma_cmd(esp, esp->command_block_dma,
830 			       val, 16, 0, start_cmd);
831 }
832 
833 static struct esp_cmd_entry *esp_get_ent(struct esp *esp)
834 {
835 	struct list_head *head = &esp->esp_cmd_pool;
836 	struct esp_cmd_entry *ret;
837 
838 	if (list_empty(head)) {
839 		ret = kzalloc(sizeof(struct esp_cmd_entry), GFP_ATOMIC);
840 	} else {
841 		ret = list_entry(head->next, struct esp_cmd_entry, list);
842 		list_del(&ret->list);
843 		memset(ret, 0, sizeof(*ret));
844 	}
845 	return ret;
846 }
847 
848 static void esp_put_ent(struct esp *esp, struct esp_cmd_entry *ent)
849 {
850 	list_add(&ent->list, &esp->esp_cmd_pool);
851 }
852 
853 static void esp_cmd_is_done(struct esp *esp, struct esp_cmd_entry *ent,
854 			    struct scsi_cmnd *cmd, unsigned int result)
855 {
856 	struct scsi_device *dev = cmd->device;
857 	int tgt = dev->id;
858 	int lun = dev->lun;
859 
860 	esp->active_cmd = NULL;
861 	esp_unmap_dma(esp, cmd);
862 	esp_free_lun_tag(ent, dev->hostdata);
863 	cmd->result = result;
864 
865 	if (ent->eh_done) {
866 		complete(ent->eh_done);
867 		ent->eh_done = NULL;
868 	}
869 
870 	if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
871 		esp->ops->unmap_single(esp, ent->sense_dma,
872 				       SCSI_SENSE_BUFFERSIZE, DMA_FROM_DEVICE);
873 		ent->sense_ptr = NULL;
874 
875 		/* Restore the message/status bytes to what we actually
876 		 * saw originally.  Also, report that we are providing
877 		 * the sense data.
878 		 */
879 		cmd->result = ((DRIVER_SENSE << 24) |
880 			       (DID_OK << 16) |
881 			       (COMMAND_COMPLETE << 8) |
882 			       (SAM_STAT_CHECK_CONDITION << 0));
883 
884 		ent->flags &= ~ESP_CMD_FLAG_AUTOSENSE;
885 		if (esp_debug & ESP_DEBUG_AUTOSENSE) {
886 			int i;
887 
888 			printk("esp%d: tgt[%d] lun[%d] AUTO SENSE[ ",
889 			       esp->host->unique_id, tgt, lun);
890 			for (i = 0; i < 18; i++)
891 				printk("%02x ", cmd->sense_buffer[i]);
892 			printk("]\n");
893 		}
894 	}
895 
896 	cmd->scsi_done(cmd);
897 
898 	list_del(&ent->list);
899 	esp_put_ent(esp, ent);
900 
901 	esp_maybe_execute_command(esp);
902 }
903 
904 static unsigned int compose_result(unsigned int status, unsigned int message,
905 				   unsigned int driver_code)
906 {
907 	return (status | (message << 8) | (driver_code << 16));
908 }
909 
910 static void esp_event_queue_full(struct esp *esp, struct esp_cmd_entry *ent)
911 {
912 	struct scsi_device *dev = ent->cmd->device;
913 	struct esp_lun_data *lp = dev->hostdata;
914 
915 	scsi_track_queue_full(dev, lp->num_tagged - 1);
916 }
917 
918 static int esp_queuecommand_lck(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
919 {
920 	struct scsi_device *dev = cmd->device;
921 	struct esp *esp = shost_priv(dev->host);
922 	struct esp_cmd_priv *spriv;
923 	struct esp_cmd_entry *ent;
924 
925 	ent = esp_get_ent(esp);
926 	if (!ent)
927 		return SCSI_MLQUEUE_HOST_BUSY;
928 
929 	ent->cmd = cmd;
930 
931 	cmd->scsi_done = done;
932 
933 	spriv = ESP_CMD_PRIV(cmd);
934 	spriv->u.dma_addr = ~(dma_addr_t)0x0;
935 
936 	list_add_tail(&ent->list, &esp->queued_cmds);
937 
938 	esp_maybe_execute_command(esp);
939 
940 	return 0;
941 }
942 
943 static DEF_SCSI_QCMD(esp_queuecommand)
944 
945 static int esp_check_gross_error(struct esp *esp)
946 {
947 	if (esp->sreg & ESP_STAT_SPAM) {
948 		/* Gross Error, could be one of:
949 		 * - top of fifo overwritten
950 		 * - top of command register overwritten
951 		 * - DMA programmed with wrong direction
952 		 * - improper phase change
953 		 */
954 		printk(KERN_ERR PFX "esp%d: Gross error sreg[%02x]\n",
955 		       esp->host->unique_id, esp->sreg);
956 		/* XXX Reset the chip. XXX */
957 		return 1;
958 	}
959 	return 0;
960 }
961 
962 static int esp_check_spur_intr(struct esp *esp)
963 {
964 	switch (esp->rev) {
965 	case ESP100:
966 	case ESP100A:
967 		/* The interrupt pending bit of the status register cannot
968 		 * be trusted on these revisions.
969 		 */
970 		esp->sreg &= ~ESP_STAT_INTR;
971 		break;
972 
973 	default:
974 		if (!(esp->sreg & ESP_STAT_INTR)) {
975 			esp->ireg = esp_read8(ESP_INTRPT);
976 			if (esp->ireg & ESP_INTR_SR)
977 				return 1;
978 
979 			/* If the DMA is indicating interrupt pending and the
980 			 * ESP is not, the only possibility is a DMA error.
981 			 */
982 			if (!esp->ops->dma_error(esp)) {
983 				printk(KERN_ERR PFX "esp%d: Spurious irq, "
984 				       "sreg=%02x.\n",
985 				       esp->host->unique_id, esp->sreg);
986 				return -1;
987 			}
988 
989 			printk(KERN_ERR PFX "esp%d: DMA error\n",
990 			       esp->host->unique_id);
991 
992 			/* XXX Reset the chip. XXX */
993 			return -1;
994 		}
995 		break;
996 	}
997 
998 	return 0;
999 }
1000 
1001 static void esp_schedule_reset(struct esp *esp)
1002 {
1003 	esp_log_reset("ESP: esp_schedule_reset() from %p\n",
1004 		      __builtin_return_address(0));
1005 	esp->flags |= ESP_FLAG_RESETTING;
1006 	esp_event(esp, ESP_EVENT_RESET);
1007 }
1008 
1009 /* In order to avoid having to add a special half-reconnected state
1010  * into the driver we just sit here and poll through the rest of
1011  * the reselection process to get the tag message bytes.
1012  */
1013 static struct esp_cmd_entry *esp_reconnect_with_tag(struct esp *esp,
1014 						    struct esp_lun_data *lp)
1015 {
1016 	struct esp_cmd_entry *ent;
1017 	int i;
1018 
1019 	if (!lp->num_tagged) {
1020 		printk(KERN_ERR PFX "esp%d: Reconnect w/num_tagged==0\n",
1021 		       esp->host->unique_id);
1022 		return NULL;
1023 	}
1024 
1025 	esp_log_reconnect("ESP: reconnect tag, ");
1026 
1027 	for (i = 0; i < ESP_QUICKIRQ_LIMIT; i++) {
1028 		if (esp->ops->irq_pending(esp))
1029 			break;
1030 	}
1031 	if (i == ESP_QUICKIRQ_LIMIT) {
1032 		printk(KERN_ERR PFX "esp%d: Reconnect IRQ1 timeout\n",
1033 		       esp->host->unique_id);
1034 		return NULL;
1035 	}
1036 
1037 	esp->sreg = esp_read8(ESP_STATUS);
1038 	esp->ireg = esp_read8(ESP_INTRPT);
1039 
1040 	esp_log_reconnect("IRQ(%d:%x:%x), ",
1041 			  i, esp->ireg, esp->sreg);
1042 
1043 	if (esp->ireg & ESP_INTR_DC) {
1044 		printk(KERN_ERR PFX "esp%d: Reconnect, got disconnect.\n",
1045 		       esp->host->unique_id);
1046 		return NULL;
1047 	}
1048 
1049 	if ((esp->sreg & ESP_STAT_PMASK) != ESP_MIP) {
1050 		printk(KERN_ERR PFX "esp%d: Reconnect, not MIP sreg[%02x].\n",
1051 		       esp->host->unique_id, esp->sreg);
1052 		return NULL;
1053 	}
1054 
1055 	/* DMA in the tag bytes... */
1056 	esp->command_block[0] = 0xff;
1057 	esp->command_block[1] = 0xff;
1058 	esp->ops->send_dma_cmd(esp, esp->command_block_dma,
1059 			       2, 2, 1, ESP_CMD_DMA | ESP_CMD_TI);
1060 
1061 	/* ACK the message.  */
1062 	scsi_esp_cmd(esp, ESP_CMD_MOK);
1063 
1064 	for (i = 0; i < ESP_RESELECT_TAG_LIMIT; i++) {
1065 		if (esp->ops->irq_pending(esp)) {
1066 			esp->sreg = esp_read8(ESP_STATUS);
1067 			esp->ireg = esp_read8(ESP_INTRPT);
1068 			if (esp->ireg & ESP_INTR_FDONE)
1069 				break;
1070 		}
1071 		udelay(1);
1072 	}
1073 	if (i == ESP_RESELECT_TAG_LIMIT) {
1074 		printk(KERN_ERR PFX "esp%d: Reconnect IRQ2 timeout\n",
1075 		       esp->host->unique_id);
1076 		return NULL;
1077 	}
1078 	esp->ops->dma_drain(esp);
1079 	esp->ops->dma_invalidate(esp);
1080 
1081 	esp_log_reconnect("IRQ2(%d:%x:%x) tag[%x:%x]\n",
1082 			  i, esp->ireg, esp->sreg,
1083 			  esp->command_block[0],
1084 			  esp->command_block[1]);
1085 
1086 	if (esp->command_block[0] < SIMPLE_QUEUE_TAG ||
1087 	    esp->command_block[0] > ORDERED_QUEUE_TAG) {
1088 		printk(KERN_ERR PFX "esp%d: Reconnect, bad tag "
1089 		       "type %02x.\n",
1090 		       esp->host->unique_id, esp->command_block[0]);
1091 		return NULL;
1092 	}
1093 
1094 	ent = lp->tagged_cmds[esp->command_block[1]];
1095 	if (!ent) {
1096 		printk(KERN_ERR PFX "esp%d: Reconnect, no entry for "
1097 		       "tag %02x.\n",
1098 		       esp->host->unique_id, esp->command_block[1]);
1099 		return NULL;
1100 	}
1101 
1102 	return ent;
1103 }
1104 
1105 static int esp_reconnect(struct esp *esp)
1106 {
1107 	struct esp_cmd_entry *ent;
1108 	struct esp_target_data *tp;
1109 	struct esp_lun_data *lp;
1110 	struct scsi_device *dev;
1111 	int target, lun;
1112 
1113 	BUG_ON(esp->active_cmd);
1114 	if (esp->rev == FASHME) {
1115 		/* FASHME puts the target and lun numbers directly
1116 		 * into the fifo.
1117 		 */
1118 		target = esp->fifo[0];
1119 		lun = esp->fifo[1] & 0x7;
1120 	} else {
1121 		u8 bits = esp_read8(ESP_FDATA);
1122 
1123 		/* Older chips put the lun directly into the fifo, but
1124 		 * the target is given as a sample of the arbitration
1125 		 * lines on the bus at reselection time.  So we should
1126 		 * see the ID of the ESP and the one reconnecting target
1127 		 * set in the bitmap.
1128 		 */
1129 		if (!(bits & esp->scsi_id_mask))
1130 			goto do_reset;
1131 		bits &= ~esp->scsi_id_mask;
1132 		if (!bits || (bits & (bits - 1)))
1133 			goto do_reset;
1134 
1135 		target = ffs(bits) - 1;
1136 		lun = (esp_read8(ESP_FDATA) & 0x7);
1137 
1138 		scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1139 		if (esp->rev == ESP100) {
1140 			u8 ireg = esp_read8(ESP_INTRPT);
1141 			/* This chip has a bug during reselection that can
1142 			 * cause a spurious illegal-command interrupt, which
1143 			 * we simply ACK here.  Another possibility is a bus
1144 			 * reset so we must check for that.
1145 			 */
1146 			if (ireg & ESP_INTR_SR)
1147 				goto do_reset;
1148 		}
1149 		scsi_esp_cmd(esp, ESP_CMD_NULL);
1150 	}
1151 
1152 	esp_write_tgt_sync(esp, target);
1153 	esp_write_tgt_config3(esp, target);
1154 
1155 	scsi_esp_cmd(esp, ESP_CMD_MOK);
1156 
1157 	if (esp->rev == FASHME)
1158 		esp_write8(target | ESP_BUSID_RESELID | ESP_BUSID_CTR32BIT,
1159 			   ESP_BUSID);
1160 
1161 	tp = &esp->target[target];
1162 	dev = __scsi_device_lookup_by_target(tp->starget, lun);
1163 	if (!dev) {
1164 		printk(KERN_ERR PFX "esp%d: Reconnect, no lp "
1165 		       "tgt[%u] lun[%u]\n",
1166 		       esp->host->unique_id, target, lun);
1167 		goto do_reset;
1168 	}
1169 	lp = dev->hostdata;
1170 
1171 	ent = lp->non_tagged_cmd;
1172 	if (!ent) {
1173 		ent = esp_reconnect_with_tag(esp, lp);
1174 		if (!ent)
1175 			goto do_reset;
1176 	}
1177 
1178 	esp->active_cmd = ent;
1179 
1180 	if (ent->flags & ESP_CMD_FLAG_ABORT) {
1181 		esp->msg_out[0] = ABORT_TASK_SET;
1182 		esp->msg_out_len = 1;
1183 		scsi_esp_cmd(esp, ESP_CMD_SATN);
1184 	}
1185 
1186 	esp_event(esp, ESP_EVENT_CHECK_PHASE);
1187 	esp_restore_pointers(esp, ent);
1188 	esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1189 	return 1;
1190 
1191 do_reset:
1192 	esp_schedule_reset(esp);
1193 	return 0;
1194 }
1195 
1196 static int esp_finish_select(struct esp *esp)
1197 {
1198 	struct esp_cmd_entry *ent;
1199 	struct scsi_cmnd *cmd;
1200 	u8 orig_select_state;
1201 
1202 	orig_select_state = esp->select_state;
1203 
1204 	/* No longer selecting.  */
1205 	esp->select_state = ESP_SELECT_NONE;
1206 
1207 	esp->seqreg = esp_read8(ESP_SSTEP) & ESP_STEP_VBITS;
1208 	ent = esp->active_cmd;
1209 	cmd = ent->cmd;
1210 
1211 	if (esp->ops->dma_error(esp)) {
1212 		/* If we see a DMA error during or as a result of selection,
1213 		 * all bets are off.
1214 		 */
1215 		esp_schedule_reset(esp);
1216 		esp_cmd_is_done(esp, ent, cmd, (DID_ERROR << 16));
1217 		return 0;
1218 	}
1219 
1220 	esp->ops->dma_invalidate(esp);
1221 
1222 	if (esp->ireg == (ESP_INTR_RSEL | ESP_INTR_FDONE)) {
1223 		struct esp_target_data *tp = &esp->target[cmd->device->id];
1224 
1225 		/* Carefully back out of the selection attempt.  Release
1226 		 * resources (such as DMA mapping & TAG) and reset state (such
1227 		 * as message out and command delivery variables).
1228 		 */
1229 		if (!(ent->flags & ESP_CMD_FLAG_AUTOSENSE)) {
1230 			esp_unmap_dma(esp, cmd);
1231 			esp_free_lun_tag(ent, cmd->device->hostdata);
1232 			tp->flags &= ~(ESP_TGT_NEGO_SYNC | ESP_TGT_NEGO_WIDE);
1233 			esp->flags &= ~ESP_FLAG_DOING_SLOWCMD;
1234 			esp->cmd_bytes_ptr = NULL;
1235 			esp->cmd_bytes_left = 0;
1236 		} else {
1237 			esp->ops->unmap_single(esp, ent->sense_dma,
1238 					       SCSI_SENSE_BUFFERSIZE,
1239 					       DMA_FROM_DEVICE);
1240 			ent->sense_ptr = NULL;
1241 		}
1242 
1243 		/* Now that the state is unwound properly, put back onto
1244 		 * the issue queue.  This command is no longer active.
1245 		 */
1246 		list_move(&ent->list, &esp->queued_cmds);
1247 		esp->active_cmd = NULL;
1248 
1249 		/* Return value ignored by caller, it directly invokes
1250 		 * esp_reconnect().
1251 		 */
1252 		return 0;
1253 	}
1254 
1255 	if (esp->ireg == ESP_INTR_DC) {
1256 		struct scsi_device *dev = cmd->device;
1257 
1258 		/* Disconnect.  Make sure we re-negotiate sync and
1259 		 * wide parameters if this target starts responding
1260 		 * again in the future.
1261 		 */
1262 		esp->target[dev->id].flags |= ESP_TGT_CHECK_NEGO;
1263 
1264 		scsi_esp_cmd(esp, ESP_CMD_ESEL);
1265 		esp_cmd_is_done(esp, ent, cmd, (DID_BAD_TARGET << 16));
1266 		return 1;
1267 	}
1268 
1269 	if (esp->ireg == (ESP_INTR_FDONE | ESP_INTR_BSERV)) {
1270 		/* Selection successful.  On pre-FAST chips we have
1271 		 * to do a NOP and possibly clean out the FIFO.
1272 		 */
1273 		if (esp->rev <= ESP236) {
1274 			int fcnt = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;
1275 
1276 			scsi_esp_cmd(esp, ESP_CMD_NULL);
1277 
1278 			if (!fcnt &&
1279 			    (!esp->prev_soff ||
1280 			     ((esp->sreg & ESP_STAT_PMASK) != ESP_DIP)))
1281 				esp_flush_fifo(esp);
1282 		}
1283 
1284 		/* If we are doing a slow command, negotiation, etc.
1285 		 * we'll do the right thing as we transition to the
1286 		 * next phase.
1287 		 */
1288 		esp_event(esp, ESP_EVENT_CHECK_PHASE);
1289 		return 0;
1290 	}
1291 
1292 	printk("ESP: Unexpected selection completion ireg[%x].\n",
1293 	       esp->ireg);
1294 	esp_schedule_reset(esp);
1295 	return 0;
1296 }
1297 
1298 static int esp_data_bytes_sent(struct esp *esp, struct esp_cmd_entry *ent,
1299 			       struct scsi_cmnd *cmd)
1300 {
1301 	int fifo_cnt, ecount, bytes_sent, flush_fifo;
1302 
1303 	fifo_cnt = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;
1304 	if (esp->prev_cfg3 & ESP_CONFIG3_EWIDE)
1305 		fifo_cnt <<= 1;
1306 
1307 	ecount = 0;
1308 	if (!(esp->sreg & ESP_STAT_TCNT)) {
1309 		ecount = ((unsigned int)esp_read8(ESP_TCLOW) |
1310 			  (((unsigned int)esp_read8(ESP_TCMED)) << 8));
1311 		if (esp->rev == FASHME)
1312 			ecount |= ((unsigned int)esp_read8(FAS_RLO)) << 16;
1313 	}
1314 
1315 	bytes_sent = esp->data_dma_len;
1316 	bytes_sent -= ecount;
1317 
1318 	if (!(ent->flags & ESP_CMD_FLAG_WRITE))
1319 		bytes_sent -= fifo_cnt;
1320 
1321 	flush_fifo = 0;
1322 	if (!esp->prev_soff) {
1323 		/* Synchronous data transfer, always flush fifo. */
1324 		flush_fifo = 1;
1325 	} else {
1326 		if (esp->rev == ESP100) {
1327 			u32 fflags, phase;
1328 
1329 			/* ESP100 has a chip bug where in the synchronous data
1330 			 * phase it can mistake a final long REQ pulse from the
1331 			 * target as an extra data byte.  Fun.
1332 			 *
1333 			 * To detect this case we resample the status register
1334 			 * and fifo flags.  If we're still in a data phase and
1335 			 * we see spurious chunks in the fifo, we return error
1336 			 * to the caller which should reset and set things up
1337 			 * such that we only try future transfers to this
1338 			 * target in synchronous mode.
1339 			 */
1340 			esp->sreg = esp_read8(ESP_STATUS);
1341 			phase = esp->sreg & ESP_STAT_PMASK;
1342 			fflags = esp_read8(ESP_FFLAGS);
1343 
1344 			if ((phase == ESP_DOP &&
1345 			     (fflags & ESP_FF_ONOTZERO)) ||
1346 			    (phase == ESP_DIP &&
1347 			     (fflags & ESP_FF_FBYTES)))
1348 				return -1;
1349 		}
1350 		if (!(ent->flags & ESP_CMD_FLAG_WRITE))
1351 			flush_fifo = 1;
1352 	}
1353 
1354 	if (flush_fifo)
1355 		esp_flush_fifo(esp);
1356 
1357 	return bytes_sent;
1358 }
1359 
1360 static void esp_setsync(struct esp *esp, struct esp_target_data *tp,
1361 			u8 scsi_period, u8 scsi_offset,
1362 			u8 esp_stp, u8 esp_soff)
1363 {
1364 	spi_period(tp->starget) = scsi_period;
1365 	spi_offset(tp->starget) = scsi_offset;
1366 	spi_width(tp->starget) = (tp->flags & ESP_TGT_WIDE) ? 1 : 0;
1367 
1368 	if (esp_soff) {
1369 		esp_stp &= 0x1f;
1370 		esp_soff |= esp->radelay;
1371 		if (esp->rev >= FAS236) {
1372 			u8 bit = ESP_CONFIG3_FSCSI;
1373 			if (esp->rev >= FAS100A)
1374 				bit = ESP_CONFIG3_FAST;
1375 
1376 			if (scsi_period < 50) {
1377 				if (esp->rev == FASHME)
1378 					esp_soff &= ~esp->radelay;
1379 				tp->esp_config3 |= bit;
1380 			} else {
1381 				tp->esp_config3 &= ~bit;
1382 			}
1383 			esp->prev_cfg3 = tp->esp_config3;
1384 			esp_write8(esp->prev_cfg3, ESP_CFG3);
1385 		}
1386 	}
1387 
1388 	tp->esp_period = esp->prev_stp = esp_stp;
1389 	tp->esp_offset = esp->prev_soff = esp_soff;
1390 
1391 	esp_write8(esp_soff, ESP_SOFF);
1392 	esp_write8(esp_stp, ESP_STP);
1393 
1394 	tp->flags &= ~(ESP_TGT_NEGO_SYNC | ESP_TGT_CHECK_NEGO);
1395 
1396 	spi_display_xfer_agreement(tp->starget);
1397 }
1398 
1399 static void esp_msgin_reject(struct esp *esp)
1400 {
1401 	struct esp_cmd_entry *ent = esp->active_cmd;
1402 	struct scsi_cmnd *cmd = ent->cmd;
1403 	struct esp_target_data *tp;
1404 	int tgt;
1405 
1406 	tgt = cmd->device->id;
1407 	tp = &esp->target[tgt];
1408 
1409 	if (tp->flags & ESP_TGT_NEGO_WIDE) {
1410 		tp->flags &= ~(ESP_TGT_NEGO_WIDE | ESP_TGT_WIDE);
1411 
1412 		if (!esp_need_to_nego_sync(tp)) {
1413 			tp->flags &= ~ESP_TGT_CHECK_NEGO;
1414 			scsi_esp_cmd(esp, ESP_CMD_RATN);
1415 		} else {
1416 			esp->msg_out_len =
1417 				spi_populate_sync_msg(&esp->msg_out[0],
1418 						      tp->nego_goal_period,
1419 						      tp->nego_goal_offset);
1420 			tp->flags |= ESP_TGT_NEGO_SYNC;
1421 			scsi_esp_cmd(esp, ESP_CMD_SATN);
1422 		}
1423 		return;
1424 	}
1425 
1426 	if (tp->flags & ESP_TGT_NEGO_SYNC) {
1427 		tp->flags &= ~(ESP_TGT_NEGO_SYNC | ESP_TGT_CHECK_NEGO);
1428 		tp->esp_period = 0;
1429 		tp->esp_offset = 0;
1430 		esp_setsync(esp, tp, 0, 0, 0, 0);
1431 		scsi_esp_cmd(esp, ESP_CMD_RATN);
1432 		return;
1433 	}
1434 
1435 	esp->msg_out[0] = ABORT_TASK_SET;
1436 	esp->msg_out_len = 1;
1437 	scsi_esp_cmd(esp, ESP_CMD_SATN);
1438 }
1439 
1440 static void esp_msgin_sdtr(struct esp *esp, struct esp_target_data *tp)
1441 {
1442 	u8 period = esp->msg_in[3];
1443 	u8 offset = esp->msg_in[4];
1444 	u8 stp;
1445 
1446 	if (!(tp->flags & ESP_TGT_NEGO_SYNC))
1447 		goto do_reject;
1448 
1449 	if (offset > 15)
1450 		goto do_reject;
1451 
1452 	if (offset) {
1453 		int one_clock;
1454 
1455 		if (period > esp->max_period) {
1456 			period = offset = 0;
1457 			goto do_sdtr;
1458 		}
1459 		if (period < esp->min_period)
1460 			goto do_reject;
1461 
1462 		one_clock = esp->ccycle / 1000;
1463 		stp = DIV_ROUND_UP(period << 2, one_clock);
1464 		if (stp && esp->rev >= FAS236) {
1465 			if (stp >= 50)
1466 				stp--;
1467 		}
1468 	} else {
1469 		stp = 0;
1470 	}
1471 
1472 	esp_setsync(esp, tp, period, offset, stp, offset);
1473 	return;
1474 
1475 do_reject:
1476 	esp->msg_out[0] = MESSAGE_REJECT;
1477 	esp->msg_out_len = 1;
1478 	scsi_esp_cmd(esp, ESP_CMD_SATN);
1479 	return;
1480 
1481 do_sdtr:
1482 	tp->nego_goal_period = period;
1483 	tp->nego_goal_offset = offset;
1484 	esp->msg_out_len =
1485 		spi_populate_sync_msg(&esp->msg_out[0],
1486 				      tp->nego_goal_period,
1487 				      tp->nego_goal_offset);
1488 	scsi_esp_cmd(esp, ESP_CMD_SATN);
1489 }
1490 
1491 static void esp_msgin_wdtr(struct esp *esp, struct esp_target_data *tp)
1492 {
1493 	int size = 8 << esp->msg_in[3];
1494 	u8 cfg3;
1495 
1496 	if (esp->rev != FASHME)
1497 		goto do_reject;
1498 
1499 	if (size != 8 && size != 16)
1500 		goto do_reject;
1501 
1502 	if (!(tp->flags & ESP_TGT_NEGO_WIDE))
1503 		goto do_reject;
1504 
1505 	cfg3 = tp->esp_config3;
1506 	if (size == 16) {
1507 		tp->flags |= ESP_TGT_WIDE;
1508 		cfg3 |= ESP_CONFIG3_EWIDE;
1509 	} else {
1510 		tp->flags &= ~ESP_TGT_WIDE;
1511 		cfg3 &= ~ESP_CONFIG3_EWIDE;
1512 	}
1513 	tp->esp_config3 = cfg3;
1514 	esp->prev_cfg3 = cfg3;
1515 	esp_write8(cfg3, ESP_CFG3);
1516 
1517 	tp->flags &= ~ESP_TGT_NEGO_WIDE;
1518 
1519 	spi_period(tp->starget) = 0;
1520 	spi_offset(tp->starget) = 0;
1521 	if (!esp_need_to_nego_sync(tp)) {
1522 		tp->flags &= ~ESP_TGT_CHECK_NEGO;
1523 		scsi_esp_cmd(esp, ESP_CMD_RATN);
1524 	} else {
1525 		esp->msg_out_len =
1526 			spi_populate_sync_msg(&esp->msg_out[0],
1527 					      tp->nego_goal_period,
1528 					      tp->nego_goal_offset);
1529 		tp->flags |= ESP_TGT_NEGO_SYNC;
1530 		scsi_esp_cmd(esp, ESP_CMD_SATN);
1531 	}
1532 	return;
1533 
1534 do_reject:
1535 	esp->msg_out[0] = MESSAGE_REJECT;
1536 	esp->msg_out_len = 1;
1537 	scsi_esp_cmd(esp, ESP_CMD_SATN);
1538 }
1539 
1540 static void esp_msgin_extended(struct esp *esp)
1541 {
1542 	struct esp_cmd_entry *ent = esp->active_cmd;
1543 	struct scsi_cmnd *cmd = ent->cmd;
1544 	struct esp_target_data *tp;
1545 	int tgt = cmd->device->id;
1546 
1547 	tp = &esp->target[tgt];
1548 	if (esp->msg_in[2] == EXTENDED_SDTR) {
1549 		esp_msgin_sdtr(esp, tp);
1550 		return;
1551 	}
1552 	if (esp->msg_in[2] == EXTENDED_WDTR) {
1553 		esp_msgin_wdtr(esp, tp);
1554 		return;
1555 	}
1556 
1557 	printk("ESP: Unexpected extended msg type %x\n",
1558 	       esp->msg_in[2]);
1559 
1560 	esp->msg_out[0] = ABORT_TASK_SET;
1561 	esp->msg_out_len = 1;
1562 	scsi_esp_cmd(esp, ESP_CMD_SATN);
1563 }
1564 
1565 /* Analyze msgin bytes received from target so far.  Return non-zero
1566  * if there are more bytes needed to complete the message.
1567  */
1568 static int esp_msgin_process(struct esp *esp)
1569 {
1570 	u8 msg0 = esp->msg_in[0];
1571 	int len = esp->msg_in_len;
1572 
1573 	if (msg0 & 0x80) {
1574 		/* Identify */
1575 		printk("ESP: Unexpected msgin identify\n");
1576 		return 0;
1577 	}
1578 
1579 	switch (msg0) {
1580 	case EXTENDED_MESSAGE:
1581 		if (len == 1)
1582 			return 1;
1583 		if (len < esp->msg_in[1] + 2)
1584 			return 1;
1585 		esp_msgin_extended(esp);
1586 		return 0;
1587 
1588 	case IGNORE_WIDE_RESIDUE: {
1589 		struct esp_cmd_entry *ent;
1590 		struct esp_cmd_priv *spriv;
1591 		if (len == 1)
1592 			return 1;
1593 
1594 		if (esp->msg_in[1] != 1)
1595 			goto do_reject;
1596 
1597 		ent = esp->active_cmd;
1598 		spriv = ESP_CMD_PRIV(ent->cmd);
1599 
1600 		if (spriv->cur_residue == sg_dma_len(spriv->cur_sg)) {
1601 			spriv->cur_sg--;
1602 			spriv->cur_residue = 1;
1603 		} else
1604 			spriv->cur_residue++;
1605 		spriv->tot_residue++;
1606 		return 0;
1607 	}
1608 	case NOP:
1609 		return 0;
1610 	case RESTORE_POINTERS:
1611 		esp_restore_pointers(esp, esp->active_cmd);
1612 		return 0;
1613 	case SAVE_POINTERS:
1614 		esp_save_pointers(esp, esp->active_cmd);
1615 		return 0;
1616 
1617 	case COMMAND_COMPLETE:
1618 	case DISCONNECT: {
1619 		struct esp_cmd_entry *ent = esp->active_cmd;
1620 
1621 		ent->message = msg0;
1622 		esp_event(esp, ESP_EVENT_FREE_BUS);
1623 		esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1624 		return 0;
1625 	}
1626 	case MESSAGE_REJECT:
1627 		esp_msgin_reject(esp);
1628 		return 0;
1629 
1630 	default:
1631 	do_reject:
1632 		esp->msg_out[0] = MESSAGE_REJECT;
1633 		esp->msg_out_len = 1;
1634 		scsi_esp_cmd(esp, ESP_CMD_SATN);
1635 		return 0;
1636 	}
1637 }
1638 
1639 static int esp_process_event(struct esp *esp)
1640 {
1641 	int write;
1642 
1643 again:
1644 	write = 0;
1645 	switch (esp->event) {
1646 	case ESP_EVENT_CHECK_PHASE:
1647 		switch (esp->sreg & ESP_STAT_PMASK) {
1648 		case ESP_DOP:
1649 			esp_event(esp, ESP_EVENT_DATA_OUT);
1650 			break;
1651 		case ESP_DIP:
1652 			esp_event(esp, ESP_EVENT_DATA_IN);
1653 			break;
1654 		case ESP_STATP:
1655 			esp_flush_fifo(esp);
1656 			scsi_esp_cmd(esp, ESP_CMD_ICCSEQ);
1657 			esp_event(esp, ESP_EVENT_STATUS);
1658 			esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1659 			return 1;
1660 
1661 		case ESP_MOP:
1662 			esp_event(esp, ESP_EVENT_MSGOUT);
1663 			break;
1664 
1665 		case ESP_MIP:
1666 			esp_event(esp, ESP_EVENT_MSGIN);
1667 			break;
1668 
1669 		case ESP_CMDP:
1670 			esp_event(esp, ESP_EVENT_CMD_START);
1671 			break;
1672 
1673 		default:
1674 			printk("ESP: Unexpected phase, sreg=%02x\n",
1675 			       esp->sreg);
1676 			esp_schedule_reset(esp);
1677 			return 0;
1678 		}
1679 		goto again;
1680 		break;
1681 
1682 	case ESP_EVENT_DATA_IN:
1683 		write = 1;
1684 		/* fallthru */
1685 
1686 	case ESP_EVENT_DATA_OUT: {
1687 		struct esp_cmd_entry *ent = esp->active_cmd;
1688 		struct scsi_cmnd *cmd = ent->cmd;
1689 		dma_addr_t dma_addr = esp_cur_dma_addr(ent, cmd);
1690 		unsigned int dma_len = esp_cur_dma_len(ent, cmd);
1691 
1692 		if (esp->rev == ESP100)
1693 			scsi_esp_cmd(esp, ESP_CMD_NULL);
1694 
1695 		if (write)
1696 			ent->flags |= ESP_CMD_FLAG_WRITE;
1697 		else
1698 			ent->flags &= ~ESP_CMD_FLAG_WRITE;
1699 
1700 		if (esp->ops->dma_length_limit)
1701 			dma_len = esp->ops->dma_length_limit(esp, dma_addr,
1702 							     dma_len);
1703 		else
1704 			dma_len = esp_dma_length_limit(esp, dma_addr, dma_len);
1705 
1706 		esp->data_dma_len = dma_len;
1707 
1708 		if (!dma_len) {
1709 			printk(KERN_ERR PFX "esp%d: DMA length is zero!\n",
1710 			       esp->host->unique_id);
1711 			printk(KERN_ERR PFX "esp%d: cur adr[%08llx] len[%08x]\n",
1712 			       esp->host->unique_id,
1713 			       (unsigned long long)esp_cur_dma_addr(ent, cmd),
1714 			       esp_cur_dma_len(ent, cmd));
1715 			esp_schedule_reset(esp);
1716 			return 0;
1717 		}
1718 
1719 		esp_log_datastart("ESP: start data addr[%08llx] len[%u] "
1720 				  "write(%d)\n",
1721 				  (unsigned long long)dma_addr, dma_len, write);
1722 
1723 		esp->ops->send_dma_cmd(esp, dma_addr, dma_len, dma_len,
1724 				       write, ESP_CMD_DMA | ESP_CMD_TI);
1725 		esp_event(esp, ESP_EVENT_DATA_DONE);
1726 		break;
1727 	}
1728 	case ESP_EVENT_DATA_DONE: {
1729 		struct esp_cmd_entry *ent = esp->active_cmd;
1730 		struct scsi_cmnd *cmd = ent->cmd;
1731 		int bytes_sent;
1732 
1733 		if (esp->ops->dma_error(esp)) {
1734 			printk("ESP: data done, DMA error, resetting\n");
1735 			esp_schedule_reset(esp);
1736 			return 0;
1737 		}
1738 
1739 		if (ent->flags & ESP_CMD_FLAG_WRITE) {
1740 			/* XXX parity errors, etc. XXX */
1741 
1742 			esp->ops->dma_drain(esp);
1743 		}
1744 		esp->ops->dma_invalidate(esp);
1745 
1746 		if (esp->ireg != ESP_INTR_BSERV) {
1747 			/* We should always see exactly a bus-service
1748 			 * interrupt at the end of a successful transfer.
1749 			 */
1750 			printk("ESP: data done, not BSERV, resetting\n");
1751 			esp_schedule_reset(esp);
1752 			return 0;
1753 		}
1754 
1755 		bytes_sent = esp_data_bytes_sent(esp, ent, cmd);
1756 
1757 		esp_log_datadone("ESP: data done flgs[%x] sent[%d]\n",
1758 				 ent->flags, bytes_sent);
1759 
1760 		if (bytes_sent < 0) {
1761 			/* XXX force sync mode for this target XXX */
1762 			esp_schedule_reset(esp);
1763 			return 0;
1764 		}
1765 
1766 		esp_advance_dma(esp, ent, cmd, bytes_sent);
1767 		esp_event(esp, ESP_EVENT_CHECK_PHASE);
1768 		goto again;
1769 	}
1770 
1771 	case ESP_EVENT_STATUS: {
1772 		struct esp_cmd_entry *ent = esp->active_cmd;
1773 
1774 		if (esp->ireg & ESP_INTR_FDONE) {
1775 			ent->status = esp_read8(ESP_FDATA);
1776 			ent->message = esp_read8(ESP_FDATA);
1777 			scsi_esp_cmd(esp, ESP_CMD_MOK);
1778 		} else if (esp->ireg == ESP_INTR_BSERV) {
1779 			ent->status = esp_read8(ESP_FDATA);
1780 			ent->message = 0xff;
1781 			esp_event(esp, ESP_EVENT_MSGIN);
1782 			return 0;
1783 		}
1784 
1785 		if (ent->message != COMMAND_COMPLETE) {
1786 			printk("ESP: Unexpected message %x in status\n",
1787 			       ent->message);
1788 			esp_schedule_reset(esp);
1789 			return 0;
1790 		}
1791 
1792 		esp_event(esp, ESP_EVENT_FREE_BUS);
1793 		esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1794 		break;
1795 	}
1796 	case ESP_EVENT_FREE_BUS: {
1797 		struct esp_cmd_entry *ent = esp->active_cmd;
1798 		struct scsi_cmnd *cmd = ent->cmd;
1799 
1800 		if (ent->message == COMMAND_COMPLETE ||
1801 		    ent->message == DISCONNECT)
1802 			scsi_esp_cmd(esp, ESP_CMD_ESEL);
1803 
1804 		if (ent->message == COMMAND_COMPLETE) {
1805 			esp_log_cmddone("ESP: Command done status[%x] "
1806 					"message[%x]\n",
1807 					ent->status, ent->message);
1808 			if (ent->status == SAM_STAT_TASK_SET_FULL)
1809 				esp_event_queue_full(esp, ent);
1810 
1811 			if (ent->status == SAM_STAT_CHECK_CONDITION &&
1812 			    !(ent->flags & ESP_CMD_FLAG_AUTOSENSE)) {
1813 				ent->flags |= ESP_CMD_FLAG_AUTOSENSE;
1814 				esp_autosense(esp, ent);
1815 			} else {
1816 				esp_cmd_is_done(esp, ent, cmd,
1817 						compose_result(ent->status,
1818 							       ent->message,
1819 							       DID_OK));
1820 			}
1821 		} else if (ent->message == DISCONNECT) {
1822 			esp_log_disconnect("ESP: Disconnecting tgt[%d] "
1823 					   "tag[%x:%x]\n",
1824 					   cmd->device->id,
1825 					   ent->tag[0], ent->tag[1]);
1826 
1827 			esp->active_cmd = NULL;
1828 			esp_maybe_execute_command(esp);
1829 		} else {
1830 			printk("ESP: Unexpected message %x in freebus\n",
1831 			       ent->message);
1832 			esp_schedule_reset(esp);
1833 			return 0;
1834 		}
1835 		if (esp->active_cmd)
1836 			esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1837 		break;
1838 	}
1839 	case ESP_EVENT_MSGOUT: {
1840 		scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1841 
1842 		if (esp_debug & ESP_DEBUG_MSGOUT) {
1843 			int i;
1844 			printk("ESP: Sending message [ ");
1845 			for (i = 0; i < esp->msg_out_len; i++)
1846 				printk("%02x ", esp->msg_out[i]);
1847 			printk("]\n");
1848 		}
1849 
1850 		if (esp->rev == FASHME) {
1851 			int i;
1852 
1853 			/* Always use the fifo.  */
1854 			for (i = 0; i < esp->msg_out_len; i++) {
1855 				esp_write8(esp->msg_out[i], ESP_FDATA);
1856 				esp_write8(0, ESP_FDATA);
1857 			}
1858 			scsi_esp_cmd(esp, ESP_CMD_TI);
1859 		} else {
1860 			if (esp->msg_out_len == 1) {
1861 				esp_write8(esp->msg_out[0], ESP_FDATA);
1862 				scsi_esp_cmd(esp, ESP_CMD_TI);
1863 			} else {
1864 				/* Use DMA. */
1865 				memcpy(esp->command_block,
1866 				       esp->msg_out,
1867 				       esp->msg_out_len);
1868 
1869 				esp->ops->send_dma_cmd(esp,
1870 						       esp->command_block_dma,
1871 						       esp->msg_out_len,
1872 						       esp->msg_out_len,
1873 						       0,
1874 						       ESP_CMD_DMA|ESP_CMD_TI);
1875 			}
1876 		}
1877 		esp_event(esp, ESP_EVENT_MSGOUT_DONE);
1878 		break;
1879 	}
1880 	case ESP_EVENT_MSGOUT_DONE:
1881 		if (esp->rev == FASHME) {
1882 			scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1883 		} else {
1884 			if (esp->msg_out_len > 1)
1885 				esp->ops->dma_invalidate(esp);
1886 		}
1887 
1888 		if (!(esp->ireg & ESP_INTR_DC)) {
1889 			if (esp->rev != FASHME)
1890 				scsi_esp_cmd(esp, ESP_CMD_NULL);
1891 		}
1892 		esp_event(esp, ESP_EVENT_CHECK_PHASE);
1893 		goto again;
1894 	case ESP_EVENT_MSGIN:
1895 		if (esp->ireg & ESP_INTR_BSERV) {
1896 			if (esp->rev == FASHME) {
1897 				if (!(esp_read8(ESP_STATUS2) &
1898 				      ESP_STAT2_FEMPTY))
1899 					scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1900 			} else {
1901 				scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1902 				if (esp->rev == ESP100)
1903 					scsi_esp_cmd(esp, ESP_CMD_NULL);
1904 			}
1905 			scsi_esp_cmd(esp, ESP_CMD_TI);
1906 			esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1907 			return 1;
1908 		}
1909 		if (esp->ireg & ESP_INTR_FDONE) {
1910 			u8 val;
1911 
1912 			if (esp->rev == FASHME)
1913 				val = esp->fifo[0];
1914 			else
1915 				val = esp_read8(ESP_FDATA);
1916 			esp->msg_in[esp->msg_in_len++] = val;
1917 
1918 			esp_log_msgin("ESP: Got msgin byte %x\n", val);
1919 
1920 			if (!esp_msgin_process(esp))
1921 				esp->msg_in_len = 0;
1922 
1923 			if (esp->rev == FASHME)
1924 				scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1925 
1926 			scsi_esp_cmd(esp, ESP_CMD_MOK);
1927 
1928 			if (esp->event != ESP_EVENT_FREE_BUS)
1929 				esp_event(esp, ESP_EVENT_CHECK_PHASE);
1930 		} else {
1931 			printk("ESP: MSGIN neither BSERV not FDON, resetting");
1932 			esp_schedule_reset(esp);
1933 			return 0;
1934 		}
1935 		break;
1936 	case ESP_EVENT_CMD_START:
1937 		memcpy(esp->command_block, esp->cmd_bytes_ptr,
1938 		       esp->cmd_bytes_left);
1939 		if (esp->rev == FASHME)
1940 			scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1941 		esp->ops->send_dma_cmd(esp, esp->command_block_dma,
1942 				       esp->cmd_bytes_left, 16, 0,
1943 				       ESP_CMD_DMA | ESP_CMD_TI);
1944 		esp_event(esp, ESP_EVENT_CMD_DONE);
1945 		esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1946 		break;
1947 	case ESP_EVENT_CMD_DONE:
1948 		esp->ops->dma_invalidate(esp);
1949 		if (esp->ireg & ESP_INTR_BSERV) {
1950 			esp_event(esp, ESP_EVENT_CHECK_PHASE);
1951 			goto again;
1952 		}
1953 		esp_schedule_reset(esp);
1954 		return 0;
1955 		break;
1956 
1957 	case ESP_EVENT_RESET:
1958 		scsi_esp_cmd(esp, ESP_CMD_RS);
1959 		break;
1960 
1961 	default:
1962 		printk("ESP: Unexpected event %x, resetting\n",
1963 		       esp->event);
1964 		esp_schedule_reset(esp);
1965 		return 0;
1966 		break;
1967 	}
1968 	return 1;
1969 }
1970 
1971 static void esp_reset_cleanup_one(struct esp *esp, struct esp_cmd_entry *ent)
1972 {
1973 	struct scsi_cmnd *cmd = ent->cmd;
1974 
1975 	esp_unmap_dma(esp, cmd);
1976 	esp_free_lun_tag(ent, cmd->device->hostdata);
1977 	cmd->result = DID_RESET << 16;
1978 
1979 	if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
1980 		esp->ops->unmap_single(esp, ent->sense_dma,
1981 				       SCSI_SENSE_BUFFERSIZE, DMA_FROM_DEVICE);
1982 		ent->sense_ptr = NULL;
1983 	}
1984 
1985 	cmd->scsi_done(cmd);
1986 	list_del(&ent->list);
1987 	esp_put_ent(esp, ent);
1988 }
1989 
1990 static void esp_clear_hold(struct scsi_device *dev, void *data)
1991 {
1992 	struct esp_lun_data *lp = dev->hostdata;
1993 
1994 	BUG_ON(lp->num_tagged);
1995 	lp->hold = 0;
1996 }
1997 
1998 static void esp_reset_cleanup(struct esp *esp)
1999 {
2000 	struct esp_cmd_entry *ent, *tmp;
2001 	int i;
2002 
2003 	list_for_each_entry_safe(ent, tmp, &esp->queued_cmds, list) {
2004 		struct scsi_cmnd *cmd = ent->cmd;
2005 
2006 		list_del(&ent->list);
2007 		cmd->result = DID_RESET << 16;
2008 		cmd->scsi_done(cmd);
2009 		esp_put_ent(esp, ent);
2010 	}
2011 
2012 	list_for_each_entry_safe(ent, tmp, &esp->active_cmds, list) {
2013 		if (ent == esp->active_cmd)
2014 			esp->active_cmd = NULL;
2015 		esp_reset_cleanup_one(esp, ent);
2016 	}
2017 
2018 	BUG_ON(esp->active_cmd != NULL);
2019 
2020 	/* Force renegotiation of sync/wide transfers.  */
2021 	for (i = 0; i < ESP_MAX_TARGET; i++) {
2022 		struct esp_target_data *tp = &esp->target[i];
2023 
2024 		tp->esp_period = 0;
2025 		tp->esp_offset = 0;
2026 		tp->esp_config3 &= ~(ESP_CONFIG3_EWIDE |
2027 				     ESP_CONFIG3_FSCSI |
2028 				     ESP_CONFIG3_FAST);
2029 		tp->flags &= ~ESP_TGT_WIDE;
2030 		tp->flags |= ESP_TGT_CHECK_NEGO;
2031 
2032 		if (tp->starget)
2033 			__starget_for_each_device(tp->starget, NULL,
2034 						  esp_clear_hold);
2035 	}
2036 	esp->flags &= ~ESP_FLAG_RESETTING;
2037 }
2038 
2039 /* Runs under host->lock */
2040 static void __esp_interrupt(struct esp *esp)
2041 {
2042 	int finish_reset, intr_done;
2043 	u8 phase;
2044 
2045 	esp->sreg = esp_read8(ESP_STATUS);
2046 
2047 	if (esp->flags & ESP_FLAG_RESETTING) {
2048 		finish_reset = 1;
2049 	} else {
2050 		if (esp_check_gross_error(esp))
2051 			return;
2052 
2053 		finish_reset = esp_check_spur_intr(esp);
2054 		if (finish_reset < 0)
2055 			return;
2056 	}
2057 
2058 	esp->ireg = esp_read8(ESP_INTRPT);
2059 
2060 	if (esp->ireg & ESP_INTR_SR)
2061 		finish_reset = 1;
2062 
2063 	if (finish_reset) {
2064 		esp_reset_cleanup(esp);
2065 		if (esp->eh_reset) {
2066 			complete(esp->eh_reset);
2067 			esp->eh_reset = NULL;
2068 		}
2069 		return;
2070 	}
2071 
2072 	phase = (esp->sreg & ESP_STAT_PMASK);
2073 	if (esp->rev == FASHME) {
2074 		if (((phase != ESP_DIP && phase != ESP_DOP) &&
2075 		     esp->select_state == ESP_SELECT_NONE &&
2076 		     esp->event != ESP_EVENT_STATUS &&
2077 		     esp->event != ESP_EVENT_DATA_DONE) ||
2078 		    (esp->ireg & ESP_INTR_RSEL)) {
2079 			esp->sreg2 = esp_read8(ESP_STATUS2);
2080 			if (!(esp->sreg2 & ESP_STAT2_FEMPTY) ||
2081 			    (esp->sreg2 & ESP_STAT2_F1BYTE))
2082 				hme_read_fifo(esp);
2083 		}
2084 	}
2085 
2086 	esp_log_intr("ESP: intr sreg[%02x] seqreg[%02x] "
2087 		     "sreg2[%02x] ireg[%02x]\n",
2088 		     esp->sreg, esp->seqreg, esp->sreg2, esp->ireg);
2089 
2090 	intr_done = 0;
2091 
2092 	if (esp->ireg & (ESP_INTR_S | ESP_INTR_SATN | ESP_INTR_IC)) {
2093 		printk("ESP: unexpected IREG %02x\n", esp->ireg);
2094 		if (esp->ireg & ESP_INTR_IC)
2095 			esp_dump_cmd_log(esp);
2096 
2097 		esp_schedule_reset(esp);
2098 	} else {
2099 		if (!(esp->ireg & ESP_INTR_RSEL)) {
2100 			/* Some combination of FDONE, BSERV, DC.  */
2101 			if (esp->select_state != ESP_SELECT_NONE)
2102 				intr_done = esp_finish_select(esp);
2103 		} else if (esp->ireg & ESP_INTR_RSEL) {
2104 			if (esp->active_cmd)
2105 				(void) esp_finish_select(esp);
2106 			intr_done = esp_reconnect(esp);
2107 		}
2108 	}
2109 	while (!intr_done)
2110 		intr_done = esp_process_event(esp);
2111 }
2112 
2113 irqreturn_t scsi_esp_intr(int irq, void *dev_id)
2114 {
2115 	struct esp *esp = dev_id;
2116 	unsigned long flags;
2117 	irqreturn_t ret;
2118 
2119 	spin_lock_irqsave(esp->host->host_lock, flags);
2120 	ret = IRQ_NONE;
2121 	if (esp->ops->irq_pending(esp)) {
2122 		ret = IRQ_HANDLED;
2123 		for (;;) {
2124 			int i;
2125 
2126 			__esp_interrupt(esp);
2127 			if (!(esp->flags & ESP_FLAG_QUICKIRQ_CHECK))
2128 				break;
2129 			esp->flags &= ~ESP_FLAG_QUICKIRQ_CHECK;
2130 
2131 			for (i = 0; i < ESP_QUICKIRQ_LIMIT; i++) {
2132 				if (esp->ops->irq_pending(esp))
2133 					break;
2134 			}
2135 			if (i == ESP_QUICKIRQ_LIMIT)
2136 				break;
2137 		}
2138 	}
2139 	spin_unlock_irqrestore(esp->host->host_lock, flags);
2140 
2141 	return ret;
2142 }
2143 EXPORT_SYMBOL(scsi_esp_intr);
2144 
2145 static void esp_get_revision(struct esp *esp)
2146 {
2147 	u8 val;
2148 
2149 	esp->config1 = (ESP_CONFIG1_PENABLE | (esp->scsi_id & 7));
2150 	esp->config2 = (ESP_CONFIG2_SCSI2ENAB | ESP_CONFIG2_REGPARITY);
2151 	esp_write8(esp->config2, ESP_CFG2);
2152 
2153 	val = esp_read8(ESP_CFG2);
2154 	val &= ~ESP_CONFIG2_MAGIC;
2155 	if (val != (ESP_CONFIG2_SCSI2ENAB | ESP_CONFIG2_REGPARITY)) {
2156 		/* If what we write to cfg2 does not come back, cfg2 is not
2157 		 * implemented, therefore this must be a plain esp100.
2158 		 */
2159 		esp->rev = ESP100;
2160 	} else {
2161 		esp->config2 = 0;
2162 		esp_set_all_config3(esp, 5);
2163 		esp->prev_cfg3 = 5;
2164 		esp_write8(esp->config2, ESP_CFG2);
2165 		esp_write8(0, ESP_CFG3);
2166 		esp_write8(esp->prev_cfg3, ESP_CFG3);
2167 
2168 		val = esp_read8(ESP_CFG3);
2169 		if (val != 5) {
2170 			/* The cfg2 register is implemented, however
2171 			 * cfg3 is not, must be esp100a.
2172 			 */
2173 			esp->rev = ESP100A;
2174 		} else {
2175 			esp_set_all_config3(esp, 0);
2176 			esp->prev_cfg3 = 0;
2177 			esp_write8(esp->prev_cfg3, ESP_CFG3);
2178 
2179 			/* All of cfg{1,2,3} implemented, must be one of
2180 			 * the fas variants, figure out which one.
2181 			 */
2182 			if (esp->cfact == 0 || esp->cfact > ESP_CCF_F5) {
2183 				esp->rev = FAST;
2184 				esp->sync_defp = SYNC_DEFP_FAST;
2185 			} else {
2186 				esp->rev = ESP236;
2187 			}
2188 			esp->config2 = 0;
2189 			esp_write8(esp->config2, ESP_CFG2);
2190 		}
2191 	}
2192 }
2193 
2194 static void esp_init_swstate(struct esp *esp)
2195 {
2196 	int i;
2197 
2198 	INIT_LIST_HEAD(&esp->queued_cmds);
2199 	INIT_LIST_HEAD(&esp->active_cmds);
2200 	INIT_LIST_HEAD(&esp->esp_cmd_pool);
2201 
2202 	/* Start with a clear state, domain validation (via ->slave_configure,
2203 	 * spi_dv_device()) will attempt to enable SYNC, WIDE, and tagged
2204 	 * commands.
2205 	 */
2206 	for (i = 0 ; i < ESP_MAX_TARGET; i++) {
2207 		esp->target[i].flags = 0;
2208 		esp->target[i].nego_goal_period = 0;
2209 		esp->target[i].nego_goal_offset = 0;
2210 		esp->target[i].nego_goal_width = 0;
2211 		esp->target[i].nego_goal_tags = 0;
2212 	}
2213 }
2214 
2215 /* This places the ESP into a known state at boot time. */
2216 static void esp_bootup_reset(struct esp *esp)
2217 {
2218 	u8 val;
2219 
2220 	/* Reset the DMA */
2221 	esp->ops->reset_dma(esp);
2222 
2223 	/* Reset the ESP */
2224 	esp_reset_esp(esp);
2225 
2226 	/* Reset the SCSI bus, but tell ESP not to generate an irq */
2227 	val = esp_read8(ESP_CFG1);
2228 	val |= ESP_CONFIG1_SRRDISAB;
2229 	esp_write8(val, ESP_CFG1);
2230 
2231 	scsi_esp_cmd(esp, ESP_CMD_RS);
2232 	udelay(400);
2233 
2234 	esp_write8(esp->config1, ESP_CFG1);
2235 
2236 	/* Eat any bitrot in the chip and we are done... */
2237 	esp_read8(ESP_INTRPT);
2238 }
2239 
2240 static void esp_set_clock_params(struct esp *esp)
2241 {
2242 	int fhz;
2243 	u8 ccf;
2244 
2245 	/* This is getting messy but it has to be done correctly or else
2246 	 * you get weird behavior all over the place.  We are trying to
2247 	 * basically figure out three pieces of information.
2248 	 *
2249 	 * a) Clock Conversion Factor
2250 	 *
2251 	 *    This is a representation of the input crystal clock frequency
2252 	 *    going into the ESP on this machine.  Any operation whose timing
2253 	 *    is longer than 400ns depends on this value being correct.  For
2254 	 *    example, you'll get blips for arbitration/selection during high
2255 	 *    load or with multiple targets if this is not set correctly.
2256 	 *
2257 	 * b) Selection Time-Out
2258 	 *
2259 	 *    The ESP isn't very bright and will arbitrate for the bus and try
2260 	 *    to select a target forever if you let it.  This value tells the
2261 	 *    ESP when it has taken too long to negotiate and that it should
2262 	 *    interrupt the CPU so we can see what happened.  The value is
2263 	 *    computed as follows (from NCR/Symbios chip docs).
2264 	 *
2265 	 *          (Time Out Period) *  (Input Clock)
2266 	 *    STO = ----------------------------------
2267 	 *          (8192) * (Clock Conversion Factor)
2268 	 *
2269 	 *    We use a time out period of 250ms (ESP_BUS_TIMEOUT).
2270 	 *
2271 	 * c) Imperical constants for synchronous offset and transfer period
2272          *    register values
2273 	 *
2274 	 *    This entails the smallest and largest sync period we could ever
2275 	 *    handle on this ESP.
2276 	 */
2277 	fhz = esp->cfreq;
2278 
2279 	ccf = ((fhz / 1000000) + 4) / 5;
2280 	if (ccf == 1)
2281 		ccf = 2;
2282 
2283 	/* If we can't find anything reasonable, just assume 20MHZ.
2284 	 * This is the clock frequency of the older sun4c's where I've
2285 	 * been unable to find the clock-frequency PROM property.  All
2286 	 * other machines provide useful values it seems.
2287 	 */
2288 	if (fhz <= 5000000 || ccf < 1 || ccf > 8) {
2289 		fhz = 20000000;
2290 		ccf = 4;
2291 	}
2292 
2293 	esp->cfact = (ccf == 8 ? 0 : ccf);
2294 	esp->cfreq = fhz;
2295 	esp->ccycle = ESP_HZ_TO_CYCLE(fhz);
2296 	esp->ctick = ESP_TICK(ccf, esp->ccycle);
2297 	esp->neg_defp = ESP_NEG_DEFP(fhz, ccf);
2298 	esp->sync_defp = SYNC_DEFP_SLOW;
2299 }
2300 
2301 static const char *esp_chip_names[] = {
2302 	"ESP100",
2303 	"ESP100A",
2304 	"ESP236",
2305 	"FAS236",
2306 	"FAS100A",
2307 	"FAST",
2308 	"FASHME",
2309 };
2310 
2311 static struct scsi_transport_template *esp_transport_template;
2312 
2313 int scsi_esp_register(struct esp *esp, struct device *dev)
2314 {
2315 	static int instance;
2316 	int err;
2317 
2318 	esp->host->transportt = esp_transport_template;
2319 	esp->host->max_lun = ESP_MAX_LUN;
2320 	esp->host->cmd_per_lun = 2;
2321 	esp->host->unique_id = instance;
2322 
2323 	esp_set_clock_params(esp);
2324 
2325 	esp_get_revision(esp);
2326 
2327 	esp_init_swstate(esp);
2328 
2329 	esp_bootup_reset(esp);
2330 
2331 	printk(KERN_INFO PFX "esp%u, regs[%1p:%1p] irq[%u]\n",
2332 	       esp->host->unique_id, esp->regs, esp->dma_regs,
2333 	       esp->host->irq);
2334 	printk(KERN_INFO PFX "esp%u is a %s, %u MHz (ccf=%u), SCSI ID %u\n",
2335 	       esp->host->unique_id, esp_chip_names[esp->rev],
2336 	       esp->cfreq / 1000000, esp->cfact, esp->scsi_id);
2337 
2338 	/* Let the SCSI bus reset settle. */
2339 	ssleep(esp_bus_reset_settle);
2340 
2341 	err = scsi_add_host(esp->host, dev);
2342 	if (err)
2343 		return err;
2344 
2345 	instance++;
2346 
2347 	scsi_scan_host(esp->host);
2348 
2349 	return 0;
2350 }
2351 EXPORT_SYMBOL(scsi_esp_register);
2352 
2353 void scsi_esp_unregister(struct esp *esp)
2354 {
2355 	scsi_remove_host(esp->host);
2356 }
2357 EXPORT_SYMBOL(scsi_esp_unregister);
2358 
2359 static int esp_target_alloc(struct scsi_target *starget)
2360 {
2361 	struct esp *esp = shost_priv(dev_to_shost(&starget->dev));
2362 	struct esp_target_data *tp = &esp->target[starget->id];
2363 
2364 	tp->starget = starget;
2365 
2366 	return 0;
2367 }
2368 
2369 static void esp_target_destroy(struct scsi_target *starget)
2370 {
2371 	struct esp *esp = shost_priv(dev_to_shost(&starget->dev));
2372 	struct esp_target_data *tp = &esp->target[starget->id];
2373 
2374 	tp->starget = NULL;
2375 }
2376 
2377 static int esp_slave_alloc(struct scsi_device *dev)
2378 {
2379 	struct esp *esp = shost_priv(dev->host);
2380 	struct esp_target_data *tp = &esp->target[dev->id];
2381 	struct esp_lun_data *lp;
2382 
2383 	lp = kzalloc(sizeof(*lp), GFP_KERNEL);
2384 	if (!lp)
2385 		return -ENOMEM;
2386 	dev->hostdata = lp;
2387 
2388 	spi_min_period(tp->starget) = esp->min_period;
2389 	spi_max_offset(tp->starget) = 15;
2390 
2391 	if (esp->flags & ESP_FLAG_WIDE_CAPABLE)
2392 		spi_max_width(tp->starget) = 1;
2393 	else
2394 		spi_max_width(tp->starget) = 0;
2395 
2396 	return 0;
2397 }
2398 
2399 static int esp_slave_configure(struct scsi_device *dev)
2400 {
2401 	struct esp *esp = shost_priv(dev->host);
2402 	struct esp_target_data *tp = &esp->target[dev->id];
2403 	int goal_tags, queue_depth;
2404 
2405 	goal_tags = 0;
2406 
2407 	if (dev->tagged_supported) {
2408 		/* XXX make this configurable somehow XXX */
2409 		goal_tags = ESP_DEFAULT_TAGS;
2410 
2411 		if (goal_tags > ESP_MAX_TAG)
2412 			goal_tags = ESP_MAX_TAG;
2413 	}
2414 
2415 	queue_depth = goal_tags;
2416 	if (queue_depth < dev->host->cmd_per_lun)
2417 		queue_depth = dev->host->cmd_per_lun;
2418 
2419 	if (goal_tags) {
2420 		scsi_set_tag_type(dev, MSG_ORDERED_TAG);
2421 		scsi_activate_tcq(dev, queue_depth);
2422 	} else {
2423 		scsi_deactivate_tcq(dev, queue_depth);
2424 	}
2425 	tp->flags |= ESP_TGT_DISCONNECT;
2426 
2427 	if (!spi_initial_dv(dev->sdev_target))
2428 		spi_dv_device(dev);
2429 
2430 	return 0;
2431 }
2432 
2433 static void esp_slave_destroy(struct scsi_device *dev)
2434 {
2435 	struct esp_lun_data *lp = dev->hostdata;
2436 
2437 	kfree(lp);
2438 	dev->hostdata = NULL;
2439 }
2440 
2441 static int esp_eh_abort_handler(struct scsi_cmnd *cmd)
2442 {
2443 	struct esp *esp = shost_priv(cmd->device->host);
2444 	struct esp_cmd_entry *ent, *tmp;
2445 	struct completion eh_done;
2446 	unsigned long flags;
2447 
2448 	/* XXX This helps a lot with debugging but might be a bit
2449 	 * XXX much for the final driver.
2450 	 */
2451 	spin_lock_irqsave(esp->host->host_lock, flags);
2452 	printk(KERN_ERR PFX "esp%d: Aborting command [%p:%02x]\n",
2453 	       esp->host->unique_id, cmd, cmd->cmnd[0]);
2454 	ent = esp->active_cmd;
2455 	if (ent)
2456 		printk(KERN_ERR PFX "esp%d: Current command [%p:%02x]\n",
2457 		       esp->host->unique_id, ent->cmd, ent->cmd->cmnd[0]);
2458 	list_for_each_entry(ent, &esp->queued_cmds, list) {
2459 		printk(KERN_ERR PFX "esp%d: Queued command [%p:%02x]\n",
2460 		       esp->host->unique_id, ent->cmd, ent->cmd->cmnd[0]);
2461 	}
2462 	list_for_each_entry(ent, &esp->active_cmds, list) {
2463 		printk(KERN_ERR PFX "esp%d: Active command [%p:%02x]\n",
2464 		       esp->host->unique_id, ent->cmd, ent->cmd->cmnd[0]);
2465 	}
2466 	esp_dump_cmd_log(esp);
2467 	spin_unlock_irqrestore(esp->host->host_lock, flags);
2468 
2469 	spin_lock_irqsave(esp->host->host_lock, flags);
2470 
2471 	ent = NULL;
2472 	list_for_each_entry(tmp, &esp->queued_cmds, list) {
2473 		if (tmp->cmd == cmd) {
2474 			ent = tmp;
2475 			break;
2476 		}
2477 	}
2478 
2479 	if (ent) {
2480 		/* Easiest case, we didn't even issue the command
2481 		 * yet so it is trivial to abort.
2482 		 */
2483 		list_del(&ent->list);
2484 
2485 		cmd->result = DID_ABORT << 16;
2486 		cmd->scsi_done(cmd);
2487 
2488 		esp_put_ent(esp, ent);
2489 
2490 		goto out_success;
2491 	}
2492 
2493 	init_completion(&eh_done);
2494 
2495 	ent = esp->active_cmd;
2496 	if (ent && ent->cmd == cmd) {
2497 		/* Command is the currently active command on
2498 		 * the bus.  If we already have an output message
2499 		 * pending, no dice.
2500 		 */
2501 		if (esp->msg_out_len)
2502 			goto out_failure;
2503 
2504 		/* Send out an abort, encouraging the target to
2505 		 * go to MSGOUT phase by asserting ATN.
2506 		 */
2507 		esp->msg_out[0] = ABORT_TASK_SET;
2508 		esp->msg_out_len = 1;
2509 		ent->eh_done = &eh_done;
2510 
2511 		scsi_esp_cmd(esp, ESP_CMD_SATN);
2512 	} else {
2513 		/* The command is disconnected.  This is not easy to
2514 		 * abort.  For now we fail and let the scsi error
2515 		 * handling layer go try a scsi bus reset or host
2516 		 * reset.
2517 		 *
2518 		 * What we could do is put together a scsi command
2519 		 * solely for the purpose of sending an abort message
2520 		 * to the target.  Coming up with all the code to
2521 		 * cook up scsi commands, special case them everywhere,
2522 		 * etc. is for questionable gain and it would be better
2523 		 * if the generic scsi error handling layer could do at
2524 		 * least some of that for us.
2525 		 *
2526 		 * Anyways this is an area for potential future improvement
2527 		 * in this driver.
2528 		 */
2529 		goto out_failure;
2530 	}
2531 
2532 	spin_unlock_irqrestore(esp->host->host_lock, flags);
2533 
2534 	if (!wait_for_completion_timeout(&eh_done, 5 * HZ)) {
2535 		spin_lock_irqsave(esp->host->host_lock, flags);
2536 		ent->eh_done = NULL;
2537 		spin_unlock_irqrestore(esp->host->host_lock, flags);
2538 
2539 		return FAILED;
2540 	}
2541 
2542 	return SUCCESS;
2543 
2544 out_success:
2545 	spin_unlock_irqrestore(esp->host->host_lock, flags);
2546 	return SUCCESS;
2547 
2548 out_failure:
2549 	/* XXX This might be a good location to set ESP_TGT_BROKEN
2550 	 * XXX since we know which target/lun in particular is
2551 	 * XXX causing trouble.
2552 	 */
2553 	spin_unlock_irqrestore(esp->host->host_lock, flags);
2554 	return FAILED;
2555 }
2556 
2557 static int esp_eh_bus_reset_handler(struct scsi_cmnd *cmd)
2558 {
2559 	struct esp *esp = shost_priv(cmd->device->host);
2560 	struct completion eh_reset;
2561 	unsigned long flags;
2562 
2563 	init_completion(&eh_reset);
2564 
2565 	spin_lock_irqsave(esp->host->host_lock, flags);
2566 
2567 	esp->eh_reset = &eh_reset;
2568 
2569 	/* XXX This is too simple... We should add lots of
2570 	 * XXX checks here so that if we find that the chip is
2571 	 * XXX very wedged we return failure immediately so
2572 	 * XXX that we can perform a full chip reset.
2573 	 */
2574 	esp->flags |= ESP_FLAG_RESETTING;
2575 	scsi_esp_cmd(esp, ESP_CMD_RS);
2576 
2577 	spin_unlock_irqrestore(esp->host->host_lock, flags);
2578 
2579 	ssleep(esp_bus_reset_settle);
2580 
2581 	if (!wait_for_completion_timeout(&eh_reset, 5 * HZ)) {
2582 		spin_lock_irqsave(esp->host->host_lock, flags);
2583 		esp->eh_reset = NULL;
2584 		spin_unlock_irqrestore(esp->host->host_lock, flags);
2585 
2586 		return FAILED;
2587 	}
2588 
2589 	return SUCCESS;
2590 }
2591 
2592 /* All bets are off, reset the entire device.  */
2593 static int esp_eh_host_reset_handler(struct scsi_cmnd *cmd)
2594 {
2595 	struct esp *esp = shost_priv(cmd->device->host);
2596 	unsigned long flags;
2597 
2598 	spin_lock_irqsave(esp->host->host_lock, flags);
2599 	esp_bootup_reset(esp);
2600 	esp_reset_cleanup(esp);
2601 	spin_unlock_irqrestore(esp->host->host_lock, flags);
2602 
2603 	ssleep(esp_bus_reset_settle);
2604 
2605 	return SUCCESS;
2606 }
2607 
2608 static const char *esp_info(struct Scsi_Host *host)
2609 {
2610 	return "esp";
2611 }
2612 
2613 struct scsi_host_template scsi_esp_template = {
2614 	.module			= THIS_MODULE,
2615 	.name			= "esp",
2616 	.info			= esp_info,
2617 	.queuecommand		= esp_queuecommand,
2618 	.target_alloc		= esp_target_alloc,
2619 	.target_destroy		= esp_target_destroy,
2620 	.slave_alloc		= esp_slave_alloc,
2621 	.slave_configure	= esp_slave_configure,
2622 	.slave_destroy		= esp_slave_destroy,
2623 	.eh_abort_handler	= esp_eh_abort_handler,
2624 	.eh_bus_reset_handler	= esp_eh_bus_reset_handler,
2625 	.eh_host_reset_handler	= esp_eh_host_reset_handler,
2626 	.can_queue		= 7,
2627 	.this_id		= 7,
2628 	.sg_tablesize		= SG_ALL,
2629 	.use_clustering		= ENABLE_CLUSTERING,
2630 	.max_sectors		= 0xffff,
2631 	.skip_settle_delay	= 1,
2632 };
2633 EXPORT_SYMBOL(scsi_esp_template);
2634 
2635 static void esp_get_signalling(struct Scsi_Host *host)
2636 {
2637 	struct esp *esp = shost_priv(host);
2638 	enum spi_signal_type type;
2639 
2640 	if (esp->flags & ESP_FLAG_DIFFERENTIAL)
2641 		type = SPI_SIGNAL_HVD;
2642 	else
2643 		type = SPI_SIGNAL_SE;
2644 
2645 	spi_signalling(host) = type;
2646 }
2647 
2648 static void esp_set_offset(struct scsi_target *target, int offset)
2649 {
2650 	struct Scsi_Host *host = dev_to_shost(target->dev.parent);
2651 	struct esp *esp = shost_priv(host);
2652 	struct esp_target_data *tp = &esp->target[target->id];
2653 
2654 	if (esp->flags & ESP_FLAG_DISABLE_SYNC)
2655 		tp->nego_goal_offset = 0;
2656 	else
2657 		tp->nego_goal_offset = offset;
2658 	tp->flags |= ESP_TGT_CHECK_NEGO;
2659 }
2660 
2661 static void esp_set_period(struct scsi_target *target, int period)
2662 {
2663 	struct Scsi_Host *host = dev_to_shost(target->dev.parent);
2664 	struct esp *esp = shost_priv(host);
2665 	struct esp_target_data *tp = &esp->target[target->id];
2666 
2667 	tp->nego_goal_period = period;
2668 	tp->flags |= ESP_TGT_CHECK_NEGO;
2669 }
2670 
2671 static void esp_set_width(struct scsi_target *target, int width)
2672 {
2673 	struct Scsi_Host *host = dev_to_shost(target->dev.parent);
2674 	struct esp *esp = shost_priv(host);
2675 	struct esp_target_data *tp = &esp->target[target->id];
2676 
2677 	tp->nego_goal_width = (width ? 1 : 0);
2678 	tp->flags |= ESP_TGT_CHECK_NEGO;
2679 }
2680 
2681 static struct spi_function_template esp_transport_ops = {
2682 	.set_offset		= esp_set_offset,
2683 	.show_offset		= 1,
2684 	.set_period		= esp_set_period,
2685 	.show_period		= 1,
2686 	.set_width		= esp_set_width,
2687 	.show_width		= 1,
2688 	.get_signalling		= esp_get_signalling,
2689 };
2690 
2691 static int __init esp_init(void)
2692 {
2693 	BUILD_BUG_ON(sizeof(struct scsi_pointer) <
2694 		     sizeof(struct esp_cmd_priv));
2695 
2696 	esp_transport_template = spi_attach_transport(&esp_transport_ops);
2697 	if (!esp_transport_template)
2698 		return -ENODEV;
2699 
2700 	return 0;
2701 }
2702 
2703 static void __exit esp_exit(void)
2704 {
2705 	spi_release_transport(esp_transport_template);
2706 }
2707 
2708 MODULE_DESCRIPTION("ESP SCSI driver core");
2709 MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
2710 MODULE_LICENSE("GPL");
2711 MODULE_VERSION(DRV_VERSION);
2712 
2713 module_param(esp_bus_reset_settle, int, 0);
2714 MODULE_PARM_DESC(esp_bus_reset_settle,
2715 		 "ESP scsi bus reset delay in seconds");
2716 
2717 module_param(esp_debug, int, 0);
2718 MODULE_PARM_DESC(esp_debug,
2719 "ESP bitmapped debugging message enable value:\n"
2720 "	0x00000001	Log interrupt events\n"
2721 "	0x00000002	Log scsi commands\n"
2722 "	0x00000004	Log resets\n"
2723 "	0x00000008	Log message in events\n"
2724 "	0x00000010	Log message out events\n"
2725 "	0x00000020	Log command completion\n"
2726 "	0x00000040	Log disconnects\n"
2727 "	0x00000080	Log data start\n"
2728 "	0x00000100	Log data done\n"
2729 "	0x00000200	Log reconnects\n"
2730 "	0x00000400	Log auto-sense data\n"
2731 );
2732 
2733 module_init(esp_init);
2734 module_exit(esp_exit);
2735