xref: /openbmc/linux/drivers/scsi/esp_scsi.c (revision 3b465a14)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* esp_scsi.c: ESP SCSI driver.
3  *
4  * Copyright (C) 2007 David S. Miller (davem@davemloft.net)
5  */
6 
7 #include <linux/kernel.h>
8 #include <linux/types.h>
9 #include <linux/slab.h>
10 #include <linux/delay.h>
11 #include <linux/list.h>
12 #include <linux/completion.h>
13 #include <linux/kallsyms.h>
14 #include <linux/module.h>
15 #include <linux/moduleparam.h>
16 #include <linux/init.h>
17 #include <linux/irqreturn.h>
18 
19 #include <asm/irq.h>
20 #include <asm/io.h>
21 #include <asm/dma.h>
22 
23 #include <scsi/scsi.h>
24 #include <scsi/scsi_host.h>
25 #include <scsi/scsi_cmnd.h>
26 #include <scsi/scsi_device.h>
27 #include <scsi/scsi_tcq.h>
28 #include <scsi/scsi_dbg.h>
29 #include <scsi/scsi_transport_spi.h>
30 
31 #include "esp_scsi.h"
32 
33 #define DRV_MODULE_NAME		"esp"
34 #define PFX DRV_MODULE_NAME	": "
35 #define DRV_VERSION		"2.000"
36 #define DRV_MODULE_RELDATE	"April 19, 2007"
37 
38 /* SCSI bus reset settle time in seconds.  */
39 static int esp_bus_reset_settle = 3;
40 
41 static u32 esp_debug;
42 #define ESP_DEBUG_INTR		0x00000001
43 #define ESP_DEBUG_SCSICMD	0x00000002
44 #define ESP_DEBUG_RESET		0x00000004
45 #define ESP_DEBUG_MSGIN		0x00000008
46 #define ESP_DEBUG_MSGOUT	0x00000010
47 #define ESP_DEBUG_CMDDONE	0x00000020
48 #define ESP_DEBUG_DISCONNECT	0x00000040
49 #define ESP_DEBUG_DATASTART	0x00000080
50 #define ESP_DEBUG_DATADONE	0x00000100
51 #define ESP_DEBUG_RECONNECT	0x00000200
52 #define ESP_DEBUG_AUTOSENSE	0x00000400
53 #define ESP_DEBUG_EVENT		0x00000800
54 #define ESP_DEBUG_COMMAND	0x00001000
55 
56 #define esp_log_intr(f, a...) \
57 do {	if (esp_debug & ESP_DEBUG_INTR) \
58 		shost_printk(KERN_DEBUG, esp->host, f, ## a);	\
59 } while (0)
60 
61 #define esp_log_reset(f, a...) \
62 do {	if (esp_debug & ESP_DEBUG_RESET) \
63 		shost_printk(KERN_DEBUG, esp->host, f, ## a);	\
64 } while (0)
65 
66 #define esp_log_msgin(f, a...) \
67 do {	if (esp_debug & ESP_DEBUG_MSGIN) \
68 		shost_printk(KERN_DEBUG, esp->host, f, ## a);	\
69 } while (0)
70 
71 #define esp_log_msgout(f, a...) \
72 do {	if (esp_debug & ESP_DEBUG_MSGOUT) \
73 		shost_printk(KERN_DEBUG, esp->host, f, ## a);	\
74 } while (0)
75 
76 #define esp_log_cmddone(f, a...) \
77 do {	if (esp_debug & ESP_DEBUG_CMDDONE) \
78 		shost_printk(KERN_DEBUG, esp->host, f, ## a);	\
79 } while (0)
80 
81 #define esp_log_disconnect(f, a...) \
82 do {	if (esp_debug & ESP_DEBUG_DISCONNECT) \
83 		shost_printk(KERN_DEBUG, esp->host, f, ## a);	\
84 } while (0)
85 
86 #define esp_log_datastart(f, a...) \
87 do {	if (esp_debug & ESP_DEBUG_DATASTART) \
88 		shost_printk(KERN_DEBUG, esp->host, f, ## a);	\
89 } while (0)
90 
91 #define esp_log_datadone(f, a...) \
92 do {	if (esp_debug & ESP_DEBUG_DATADONE) \
93 		shost_printk(KERN_DEBUG, esp->host, f, ## a);	\
94 } while (0)
95 
96 #define esp_log_reconnect(f, a...) \
97 do {	if (esp_debug & ESP_DEBUG_RECONNECT) \
98 		shost_printk(KERN_DEBUG, esp->host, f, ## a);	\
99 } while (0)
100 
101 #define esp_log_autosense(f, a...) \
102 do {	if (esp_debug & ESP_DEBUG_AUTOSENSE) \
103 		shost_printk(KERN_DEBUG, esp->host, f, ## a);	\
104 } while (0)
105 
106 #define esp_log_event(f, a...) \
107 do {   if (esp_debug & ESP_DEBUG_EVENT)	\
108 		shost_printk(KERN_DEBUG, esp->host, f, ## a);	\
109 } while (0)
110 
111 #define esp_log_command(f, a...) \
112 do {   if (esp_debug & ESP_DEBUG_COMMAND)	\
113 		shost_printk(KERN_DEBUG, esp->host, f, ## a);	\
114 } while (0)
115 
116 #define esp_read8(REG)		esp->ops->esp_read8(esp, REG)
117 #define esp_write8(VAL,REG)	esp->ops->esp_write8(esp, VAL, REG)
118 
esp_log_fill_regs(struct esp * esp,struct esp_event_ent * p)119 static void esp_log_fill_regs(struct esp *esp,
120 			      struct esp_event_ent *p)
121 {
122 	p->sreg = esp->sreg;
123 	p->seqreg = esp->seqreg;
124 	p->sreg2 = esp->sreg2;
125 	p->ireg = esp->ireg;
126 	p->select_state = esp->select_state;
127 	p->event = esp->event;
128 }
129 
scsi_esp_cmd(struct esp * esp,u8 val)130 void scsi_esp_cmd(struct esp *esp, u8 val)
131 {
132 	struct esp_event_ent *p;
133 	int idx = esp->esp_event_cur;
134 
135 	p = &esp->esp_event_log[idx];
136 	p->type = ESP_EVENT_TYPE_CMD;
137 	p->val = val;
138 	esp_log_fill_regs(esp, p);
139 
140 	esp->esp_event_cur = (idx + 1) & (ESP_EVENT_LOG_SZ - 1);
141 
142 	esp_log_command("cmd[%02x]\n", val);
143 	esp_write8(val, ESP_CMD);
144 }
145 EXPORT_SYMBOL(scsi_esp_cmd);
146 
esp_send_dma_cmd(struct esp * esp,int len,int max_len,int cmd)147 static void esp_send_dma_cmd(struct esp *esp, int len, int max_len, int cmd)
148 {
149 	if (esp->flags & ESP_FLAG_USE_FIFO) {
150 		int i;
151 
152 		scsi_esp_cmd(esp, ESP_CMD_FLUSH);
153 		for (i = 0; i < len; i++)
154 			esp_write8(esp->command_block[i], ESP_FDATA);
155 		scsi_esp_cmd(esp, cmd);
156 	} else {
157 		if (esp->rev == FASHME)
158 			scsi_esp_cmd(esp, ESP_CMD_FLUSH);
159 		cmd |= ESP_CMD_DMA;
160 		esp->ops->send_dma_cmd(esp, esp->command_block_dma,
161 				       len, max_len, 0, cmd);
162 	}
163 }
164 
esp_event(struct esp * esp,u8 val)165 static void esp_event(struct esp *esp, u8 val)
166 {
167 	struct esp_event_ent *p;
168 	int idx = esp->esp_event_cur;
169 
170 	p = &esp->esp_event_log[idx];
171 	p->type = ESP_EVENT_TYPE_EVENT;
172 	p->val = val;
173 	esp_log_fill_regs(esp, p);
174 
175 	esp->esp_event_cur = (idx + 1) & (ESP_EVENT_LOG_SZ - 1);
176 
177 	esp->event = val;
178 }
179 
esp_dump_cmd_log(struct esp * esp)180 static void esp_dump_cmd_log(struct esp *esp)
181 {
182 	int idx = esp->esp_event_cur;
183 	int stop = idx;
184 
185 	shost_printk(KERN_INFO, esp->host, "Dumping command log\n");
186 	do {
187 		struct esp_event_ent *p = &esp->esp_event_log[idx];
188 
189 		shost_printk(KERN_INFO, esp->host,
190 			     "ent[%d] %s val[%02x] sreg[%02x] seqreg[%02x] "
191 			     "sreg2[%02x] ireg[%02x] ss[%02x] event[%02x]\n",
192 			     idx,
193 			     p->type == ESP_EVENT_TYPE_CMD ? "CMD" : "EVENT",
194 			     p->val, p->sreg, p->seqreg,
195 			     p->sreg2, p->ireg, p->select_state, p->event);
196 
197 		idx = (idx + 1) & (ESP_EVENT_LOG_SZ - 1);
198 	} while (idx != stop);
199 }
200 
esp_flush_fifo(struct esp * esp)201 static void esp_flush_fifo(struct esp *esp)
202 {
203 	scsi_esp_cmd(esp, ESP_CMD_FLUSH);
204 	if (esp->rev == ESP236) {
205 		int lim = 1000;
206 
207 		while (esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES) {
208 			if (--lim == 0) {
209 				shost_printk(KERN_ALERT, esp->host,
210 					     "ESP_FF_BYTES will not clear!\n");
211 				break;
212 			}
213 			udelay(1);
214 		}
215 	}
216 }
217 
hme_read_fifo(struct esp * esp)218 static void hme_read_fifo(struct esp *esp)
219 {
220 	int fcnt = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;
221 	int idx = 0;
222 
223 	while (fcnt--) {
224 		esp->fifo[idx++] = esp_read8(ESP_FDATA);
225 		esp->fifo[idx++] = esp_read8(ESP_FDATA);
226 	}
227 	if (esp->sreg2 & ESP_STAT2_F1BYTE) {
228 		esp_write8(0, ESP_FDATA);
229 		esp->fifo[idx++] = esp_read8(ESP_FDATA);
230 		scsi_esp_cmd(esp, ESP_CMD_FLUSH);
231 	}
232 	esp->fifo_cnt = idx;
233 }
234 
esp_set_all_config3(struct esp * esp,u8 val)235 static void esp_set_all_config3(struct esp *esp, u8 val)
236 {
237 	int i;
238 
239 	for (i = 0; i < ESP_MAX_TARGET; i++)
240 		esp->target[i].esp_config3 = val;
241 }
242 
243 /* Reset the ESP chip, _not_ the SCSI bus. */
esp_reset_esp(struct esp * esp)244 static void esp_reset_esp(struct esp *esp)
245 {
246 	/* Now reset the ESP chip */
247 	scsi_esp_cmd(esp, ESP_CMD_RC);
248 	scsi_esp_cmd(esp, ESP_CMD_NULL | ESP_CMD_DMA);
249 	if (esp->rev == FAST)
250 		esp_write8(ESP_CONFIG2_FENAB, ESP_CFG2);
251 	scsi_esp_cmd(esp, ESP_CMD_NULL | ESP_CMD_DMA);
252 
253 	/* This is the only point at which it is reliable to read
254 	 * the ID-code for a fast ESP chip variants.
255 	 */
256 	esp->max_period = ((35 * esp->ccycle) / 1000);
257 	if (esp->rev == FAST) {
258 		u8 family_code = ESP_FAMILY(esp_read8(ESP_UID));
259 
260 		if (family_code == ESP_UID_F236) {
261 			esp->rev = FAS236;
262 		} else if (family_code == ESP_UID_HME) {
263 			esp->rev = FASHME; /* Version is usually '5'. */
264 		} else if (family_code == ESP_UID_FSC) {
265 			esp->rev = FSC;
266 			/* Enable Active Negation */
267 			esp_write8(ESP_CONFIG4_RADE, ESP_CFG4);
268 		} else {
269 			esp->rev = FAS100A;
270 		}
271 		esp->min_period = ((4 * esp->ccycle) / 1000);
272 	} else {
273 		esp->min_period = ((5 * esp->ccycle) / 1000);
274 	}
275 	if (esp->rev == FAS236) {
276 		/*
277 		 * The AM53c974 chip returns the same ID as FAS236;
278 		 * try to configure glitch eater.
279 		 */
280 		u8 config4 = ESP_CONFIG4_GE1;
281 		esp_write8(config4, ESP_CFG4);
282 		config4 = esp_read8(ESP_CFG4);
283 		if (config4 & ESP_CONFIG4_GE1) {
284 			esp->rev = PCSCSI;
285 			esp_write8(esp->config4, ESP_CFG4);
286 		}
287 	}
288 	esp->max_period = (esp->max_period + 3)>>2;
289 	esp->min_period = (esp->min_period + 3)>>2;
290 
291 	esp_write8(esp->config1, ESP_CFG1);
292 	switch (esp->rev) {
293 	case ESP100:
294 		/* nothing to do */
295 		break;
296 
297 	case ESP100A:
298 		esp_write8(esp->config2, ESP_CFG2);
299 		break;
300 
301 	case ESP236:
302 		/* Slow 236 */
303 		esp_write8(esp->config2, ESP_CFG2);
304 		esp->prev_cfg3 = esp->target[0].esp_config3;
305 		esp_write8(esp->prev_cfg3, ESP_CFG3);
306 		break;
307 
308 	case FASHME:
309 		esp->config2 |= (ESP_CONFIG2_HME32 | ESP_CONFIG2_HMEFENAB);
310 		fallthrough;
311 
312 	case FAS236:
313 	case PCSCSI:
314 	case FSC:
315 		esp_write8(esp->config2, ESP_CFG2);
316 		if (esp->rev == FASHME) {
317 			u8 cfg3 = esp->target[0].esp_config3;
318 
319 			cfg3 |= ESP_CONFIG3_FCLOCK | ESP_CONFIG3_OBPUSH;
320 			if (esp->scsi_id >= 8)
321 				cfg3 |= ESP_CONFIG3_IDBIT3;
322 			esp_set_all_config3(esp, cfg3);
323 		} else {
324 			u32 cfg3 = esp->target[0].esp_config3;
325 
326 			cfg3 |= ESP_CONFIG3_FCLK;
327 			esp_set_all_config3(esp, cfg3);
328 		}
329 		esp->prev_cfg3 = esp->target[0].esp_config3;
330 		esp_write8(esp->prev_cfg3, ESP_CFG3);
331 		if (esp->rev == FASHME) {
332 			esp->radelay = 80;
333 		} else {
334 			if (esp->flags & ESP_FLAG_DIFFERENTIAL)
335 				esp->radelay = 0;
336 			else
337 				esp->radelay = 96;
338 		}
339 		break;
340 
341 	case FAS100A:
342 		/* Fast 100a */
343 		esp_write8(esp->config2, ESP_CFG2);
344 		esp_set_all_config3(esp,
345 				    (esp->target[0].esp_config3 |
346 				     ESP_CONFIG3_FCLOCK));
347 		esp->prev_cfg3 = esp->target[0].esp_config3;
348 		esp_write8(esp->prev_cfg3, ESP_CFG3);
349 		esp->radelay = 32;
350 		break;
351 
352 	default:
353 		break;
354 	}
355 
356 	/* Reload the configuration registers */
357 	esp_write8(esp->cfact, ESP_CFACT);
358 
359 	esp->prev_stp = 0;
360 	esp_write8(esp->prev_stp, ESP_STP);
361 
362 	esp->prev_soff = 0;
363 	esp_write8(esp->prev_soff, ESP_SOFF);
364 
365 	esp_write8(esp->neg_defp, ESP_TIMEO);
366 
367 	/* Eat any bitrot in the chip */
368 	esp_read8(ESP_INTRPT);
369 	udelay(100);
370 }
371 
esp_map_dma(struct esp * esp,struct scsi_cmnd * cmd)372 static void esp_map_dma(struct esp *esp, struct scsi_cmnd *cmd)
373 {
374 	struct esp_cmd_priv *spriv = ESP_CMD_PRIV(cmd);
375 	struct scatterlist *sg = scsi_sglist(cmd);
376 	int total = 0, i;
377 	struct scatterlist *s;
378 
379 	if (cmd->sc_data_direction == DMA_NONE)
380 		return;
381 
382 	if (esp->flags & ESP_FLAG_NO_DMA_MAP) {
383 		/*
384 		 * For pseudo DMA and PIO we need the virtual address instead of
385 		 * a dma address, so perform an identity mapping.
386 		 */
387 		spriv->num_sg = scsi_sg_count(cmd);
388 
389 		scsi_for_each_sg(cmd, s, spriv->num_sg, i) {
390 			s->dma_address = (uintptr_t)sg_virt(s);
391 			total += sg_dma_len(s);
392 		}
393 	} else {
394 		spriv->num_sg = scsi_dma_map(cmd);
395 		scsi_for_each_sg(cmd, s, spriv->num_sg, i)
396 			total += sg_dma_len(s);
397 	}
398 	spriv->cur_residue = sg_dma_len(sg);
399 	spriv->prv_sg = NULL;
400 	spriv->cur_sg = sg;
401 	spriv->tot_residue = total;
402 }
403 
esp_cur_dma_addr(struct esp_cmd_entry * ent,struct scsi_cmnd * cmd)404 static dma_addr_t esp_cur_dma_addr(struct esp_cmd_entry *ent,
405 				   struct scsi_cmnd *cmd)
406 {
407 	struct esp_cmd_priv *p = ESP_CMD_PRIV(cmd);
408 
409 	if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
410 		return ent->sense_dma +
411 			(ent->sense_ptr - cmd->sense_buffer);
412 	}
413 
414 	return sg_dma_address(p->cur_sg) +
415 		(sg_dma_len(p->cur_sg) -
416 		 p->cur_residue);
417 }
418 
esp_cur_dma_len(struct esp_cmd_entry * ent,struct scsi_cmnd * cmd)419 static unsigned int esp_cur_dma_len(struct esp_cmd_entry *ent,
420 				    struct scsi_cmnd *cmd)
421 {
422 	struct esp_cmd_priv *p = ESP_CMD_PRIV(cmd);
423 
424 	if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
425 		return SCSI_SENSE_BUFFERSIZE -
426 			(ent->sense_ptr - cmd->sense_buffer);
427 	}
428 	return p->cur_residue;
429 }
430 
esp_advance_dma(struct esp * esp,struct esp_cmd_entry * ent,struct scsi_cmnd * cmd,unsigned int len)431 static void esp_advance_dma(struct esp *esp, struct esp_cmd_entry *ent,
432 			    struct scsi_cmnd *cmd, unsigned int len)
433 {
434 	struct esp_cmd_priv *p = ESP_CMD_PRIV(cmd);
435 
436 	if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
437 		ent->sense_ptr += len;
438 		return;
439 	}
440 
441 	p->cur_residue -= len;
442 	p->tot_residue -= len;
443 	if (p->cur_residue < 0 || p->tot_residue < 0) {
444 		shost_printk(KERN_ERR, esp->host,
445 			     "Data transfer overflow.\n");
446 		shost_printk(KERN_ERR, esp->host,
447 			     "cur_residue[%d] tot_residue[%d] len[%u]\n",
448 			     p->cur_residue, p->tot_residue, len);
449 		p->cur_residue = 0;
450 		p->tot_residue = 0;
451 	}
452 	if (!p->cur_residue && p->tot_residue) {
453 		p->prv_sg = p->cur_sg;
454 		p->cur_sg = sg_next(p->cur_sg);
455 		p->cur_residue = sg_dma_len(p->cur_sg);
456 	}
457 }
458 
esp_unmap_dma(struct esp * esp,struct scsi_cmnd * cmd)459 static void esp_unmap_dma(struct esp *esp, struct scsi_cmnd *cmd)
460 {
461 	if (!(esp->flags & ESP_FLAG_NO_DMA_MAP))
462 		scsi_dma_unmap(cmd);
463 }
464 
esp_save_pointers(struct esp * esp,struct esp_cmd_entry * ent)465 static void esp_save_pointers(struct esp *esp, struct esp_cmd_entry *ent)
466 {
467 	struct scsi_cmnd *cmd = ent->cmd;
468 	struct esp_cmd_priv *spriv = ESP_CMD_PRIV(cmd);
469 
470 	if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
471 		ent->saved_sense_ptr = ent->sense_ptr;
472 		return;
473 	}
474 	ent->saved_cur_residue = spriv->cur_residue;
475 	ent->saved_prv_sg = spriv->prv_sg;
476 	ent->saved_cur_sg = spriv->cur_sg;
477 	ent->saved_tot_residue = spriv->tot_residue;
478 }
479 
esp_restore_pointers(struct esp * esp,struct esp_cmd_entry * ent)480 static void esp_restore_pointers(struct esp *esp, struct esp_cmd_entry *ent)
481 {
482 	struct scsi_cmnd *cmd = ent->cmd;
483 	struct esp_cmd_priv *spriv = ESP_CMD_PRIV(cmd);
484 
485 	if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
486 		ent->sense_ptr = ent->saved_sense_ptr;
487 		return;
488 	}
489 	spriv->cur_residue = ent->saved_cur_residue;
490 	spriv->prv_sg = ent->saved_prv_sg;
491 	spriv->cur_sg = ent->saved_cur_sg;
492 	spriv->tot_residue = ent->saved_tot_residue;
493 }
494 
esp_write_tgt_config3(struct esp * esp,int tgt)495 static void esp_write_tgt_config3(struct esp *esp, int tgt)
496 {
497 	if (esp->rev > ESP100A) {
498 		u8 val = esp->target[tgt].esp_config3;
499 
500 		if (val != esp->prev_cfg3) {
501 			esp->prev_cfg3 = val;
502 			esp_write8(val, ESP_CFG3);
503 		}
504 	}
505 }
506 
esp_write_tgt_sync(struct esp * esp,int tgt)507 static void esp_write_tgt_sync(struct esp *esp, int tgt)
508 {
509 	u8 off = esp->target[tgt].esp_offset;
510 	u8 per = esp->target[tgt].esp_period;
511 
512 	if (off != esp->prev_soff) {
513 		esp->prev_soff = off;
514 		esp_write8(off, ESP_SOFF);
515 	}
516 	if (per != esp->prev_stp) {
517 		esp->prev_stp = per;
518 		esp_write8(per, ESP_STP);
519 	}
520 }
521 
esp_dma_length_limit(struct esp * esp,u32 dma_addr,u32 dma_len)522 static u32 esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len)
523 {
524 	if (esp->rev == FASHME) {
525 		/* Arbitrary segment boundaries, 24-bit counts.  */
526 		if (dma_len > (1U << 24))
527 			dma_len = (1U << 24);
528 	} else {
529 		u32 base, end;
530 
531 		/* ESP chip limits other variants by 16-bits of transfer
532 		 * count.  Actually on FAS100A and FAS236 we could get
533 		 * 24-bits of transfer count by enabling ESP_CONFIG2_FENAB
534 		 * in the ESP_CFG2 register but that causes other unwanted
535 		 * changes so we don't use it currently.
536 		 */
537 		if (dma_len > (1U << 16))
538 			dma_len = (1U << 16);
539 
540 		/* All of the DMA variants hooked up to these chips
541 		 * cannot handle crossing a 24-bit address boundary.
542 		 */
543 		base = dma_addr & ((1U << 24) - 1U);
544 		end = base + dma_len;
545 		if (end > (1U << 24))
546 			end = (1U <<24);
547 		dma_len = end - base;
548 	}
549 	return dma_len;
550 }
551 
esp_need_to_nego_wide(struct esp_target_data * tp)552 static int esp_need_to_nego_wide(struct esp_target_data *tp)
553 {
554 	struct scsi_target *target = tp->starget;
555 
556 	return spi_width(target) != tp->nego_goal_width;
557 }
558 
esp_need_to_nego_sync(struct esp_target_data * tp)559 static int esp_need_to_nego_sync(struct esp_target_data *tp)
560 {
561 	struct scsi_target *target = tp->starget;
562 
563 	/* When offset is zero, period is "don't care".  */
564 	if (!spi_offset(target) && !tp->nego_goal_offset)
565 		return 0;
566 
567 	if (spi_offset(target) == tp->nego_goal_offset &&
568 	    spi_period(target) == tp->nego_goal_period)
569 		return 0;
570 
571 	return 1;
572 }
573 
esp_alloc_lun_tag(struct esp_cmd_entry * ent,struct esp_lun_data * lp)574 static int esp_alloc_lun_tag(struct esp_cmd_entry *ent,
575 			     struct esp_lun_data *lp)
576 {
577 	if (!ent->orig_tag[0]) {
578 		/* Non-tagged, slot already taken?  */
579 		if (lp->non_tagged_cmd)
580 			return -EBUSY;
581 
582 		if (lp->hold) {
583 			/* We are being held by active tagged
584 			 * commands.
585 			 */
586 			if (lp->num_tagged)
587 				return -EBUSY;
588 
589 			/* Tagged commands completed, we can unplug
590 			 * the queue and run this untagged command.
591 			 */
592 			lp->hold = 0;
593 		} else if (lp->num_tagged) {
594 			/* Plug the queue until num_tagged decreases
595 			 * to zero in esp_free_lun_tag.
596 			 */
597 			lp->hold = 1;
598 			return -EBUSY;
599 		}
600 
601 		lp->non_tagged_cmd = ent;
602 		return 0;
603 	}
604 
605 	/* Tagged command. Check that it isn't blocked by a non-tagged one. */
606 	if (lp->non_tagged_cmd || lp->hold)
607 		return -EBUSY;
608 
609 	BUG_ON(lp->tagged_cmds[ent->orig_tag[1]]);
610 
611 	lp->tagged_cmds[ent->orig_tag[1]] = ent;
612 	lp->num_tagged++;
613 
614 	return 0;
615 }
616 
esp_free_lun_tag(struct esp_cmd_entry * ent,struct esp_lun_data * lp)617 static void esp_free_lun_tag(struct esp_cmd_entry *ent,
618 			     struct esp_lun_data *lp)
619 {
620 	if (ent->orig_tag[0]) {
621 		BUG_ON(lp->tagged_cmds[ent->orig_tag[1]] != ent);
622 		lp->tagged_cmds[ent->orig_tag[1]] = NULL;
623 		lp->num_tagged--;
624 	} else {
625 		BUG_ON(lp->non_tagged_cmd != ent);
626 		lp->non_tagged_cmd = NULL;
627 	}
628 }
629 
esp_map_sense(struct esp * esp,struct esp_cmd_entry * ent)630 static void esp_map_sense(struct esp *esp, struct esp_cmd_entry *ent)
631 {
632 	ent->sense_ptr = ent->cmd->sense_buffer;
633 	if (esp->flags & ESP_FLAG_NO_DMA_MAP) {
634 		ent->sense_dma = (uintptr_t)ent->sense_ptr;
635 		return;
636 	}
637 
638 	ent->sense_dma = dma_map_single(esp->dev, ent->sense_ptr,
639 					SCSI_SENSE_BUFFERSIZE, DMA_FROM_DEVICE);
640 }
641 
esp_unmap_sense(struct esp * esp,struct esp_cmd_entry * ent)642 static void esp_unmap_sense(struct esp *esp, struct esp_cmd_entry *ent)
643 {
644 	if (!(esp->flags & ESP_FLAG_NO_DMA_MAP))
645 		dma_unmap_single(esp->dev, ent->sense_dma,
646 				 SCSI_SENSE_BUFFERSIZE, DMA_FROM_DEVICE);
647 	ent->sense_ptr = NULL;
648 }
649 
650 /* When a contingent allegiance condition is created, we force feed a
651  * REQUEST_SENSE command to the device to fetch the sense data.  I
652  * tried many other schemes, relying on the scsi error handling layer
653  * to send out the REQUEST_SENSE automatically, but this was difficult
654  * to get right especially in the presence of applications like smartd
655  * which use SG_IO to send out their own REQUEST_SENSE commands.
656  */
esp_autosense(struct esp * esp,struct esp_cmd_entry * ent)657 static void esp_autosense(struct esp *esp, struct esp_cmd_entry *ent)
658 {
659 	struct scsi_cmnd *cmd = ent->cmd;
660 	struct scsi_device *dev = cmd->device;
661 	int tgt, lun;
662 	u8 *p, val;
663 
664 	tgt = dev->id;
665 	lun = dev->lun;
666 
667 
668 	if (!ent->sense_ptr) {
669 		esp_log_autosense("Doing auto-sense for tgt[%d] lun[%d]\n",
670 				  tgt, lun);
671 		esp_map_sense(esp, ent);
672 	}
673 	ent->saved_sense_ptr = ent->sense_ptr;
674 
675 	esp->active_cmd = ent;
676 
677 	p = esp->command_block;
678 	esp->msg_out_len = 0;
679 
680 	*p++ = IDENTIFY(0, lun);
681 	*p++ = REQUEST_SENSE;
682 	*p++ = ((dev->scsi_level <= SCSI_2) ?
683 		(lun << 5) : 0);
684 	*p++ = 0;
685 	*p++ = 0;
686 	*p++ = SCSI_SENSE_BUFFERSIZE;
687 	*p++ = 0;
688 
689 	esp->select_state = ESP_SELECT_BASIC;
690 
691 	val = tgt;
692 	if (esp->rev == FASHME)
693 		val |= ESP_BUSID_RESELID | ESP_BUSID_CTR32BIT;
694 	esp_write8(val, ESP_BUSID);
695 
696 	esp_write_tgt_sync(esp, tgt);
697 	esp_write_tgt_config3(esp, tgt);
698 
699 	val = (p - esp->command_block);
700 
701 	esp_send_dma_cmd(esp, val, 16, ESP_CMD_SELA);
702 }
703 
find_and_prep_issuable_command(struct esp * esp)704 static struct esp_cmd_entry *find_and_prep_issuable_command(struct esp *esp)
705 {
706 	struct esp_cmd_entry *ent;
707 
708 	list_for_each_entry(ent, &esp->queued_cmds, list) {
709 		struct scsi_cmnd *cmd = ent->cmd;
710 		struct scsi_device *dev = cmd->device;
711 		struct esp_lun_data *lp = dev->hostdata;
712 
713 		if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
714 			ent->tag[0] = 0;
715 			ent->tag[1] = 0;
716 			return ent;
717 		}
718 
719 		if (!spi_populate_tag_msg(&ent->tag[0], cmd)) {
720 			ent->tag[0] = 0;
721 			ent->tag[1] = 0;
722 		}
723 		ent->orig_tag[0] = ent->tag[0];
724 		ent->orig_tag[1] = ent->tag[1];
725 
726 		if (esp_alloc_lun_tag(ent, lp) < 0)
727 			continue;
728 
729 		return ent;
730 	}
731 
732 	return NULL;
733 }
734 
esp_maybe_execute_command(struct esp * esp)735 static void esp_maybe_execute_command(struct esp *esp)
736 {
737 	struct esp_target_data *tp;
738 	struct scsi_device *dev;
739 	struct scsi_cmnd *cmd;
740 	struct esp_cmd_entry *ent;
741 	bool select_and_stop = false;
742 	int tgt, lun, i;
743 	u32 val, start_cmd;
744 	u8 *p;
745 
746 	if (esp->active_cmd ||
747 	    (esp->flags & ESP_FLAG_RESETTING))
748 		return;
749 
750 	ent = find_and_prep_issuable_command(esp);
751 	if (!ent)
752 		return;
753 
754 	if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
755 		esp_autosense(esp, ent);
756 		return;
757 	}
758 
759 	cmd = ent->cmd;
760 	dev = cmd->device;
761 	tgt = dev->id;
762 	lun = dev->lun;
763 	tp = &esp->target[tgt];
764 
765 	list_move(&ent->list, &esp->active_cmds);
766 
767 	esp->active_cmd = ent;
768 
769 	esp_map_dma(esp, cmd);
770 	esp_save_pointers(esp, ent);
771 
772 	if (!(cmd->cmd_len == 6 || cmd->cmd_len == 10 || cmd->cmd_len == 12))
773 		select_and_stop = true;
774 
775 	p = esp->command_block;
776 
777 	esp->msg_out_len = 0;
778 	if (tp->flags & ESP_TGT_CHECK_NEGO) {
779 		/* Need to negotiate.  If the target is broken
780 		 * go for synchronous transfers and non-wide.
781 		 */
782 		if (tp->flags & ESP_TGT_BROKEN) {
783 			tp->flags &= ~ESP_TGT_DISCONNECT;
784 			tp->nego_goal_period = 0;
785 			tp->nego_goal_offset = 0;
786 			tp->nego_goal_width = 0;
787 			tp->nego_goal_tags = 0;
788 		}
789 
790 		/* If the settings are not changing, skip this.  */
791 		if (spi_width(tp->starget) == tp->nego_goal_width &&
792 		    spi_period(tp->starget) == tp->nego_goal_period &&
793 		    spi_offset(tp->starget) == tp->nego_goal_offset) {
794 			tp->flags &= ~ESP_TGT_CHECK_NEGO;
795 			goto build_identify;
796 		}
797 
798 		if (esp->rev == FASHME && esp_need_to_nego_wide(tp)) {
799 			esp->msg_out_len =
800 				spi_populate_width_msg(&esp->msg_out[0],
801 						       (tp->nego_goal_width ?
802 							1 : 0));
803 			tp->flags |= ESP_TGT_NEGO_WIDE;
804 		} else if (esp_need_to_nego_sync(tp)) {
805 			esp->msg_out_len =
806 				spi_populate_sync_msg(&esp->msg_out[0],
807 						      tp->nego_goal_period,
808 						      tp->nego_goal_offset);
809 			tp->flags |= ESP_TGT_NEGO_SYNC;
810 		} else {
811 			tp->flags &= ~ESP_TGT_CHECK_NEGO;
812 		}
813 
814 		/* If there are multiple message bytes, use Select and Stop */
815 		if (esp->msg_out_len)
816 			select_and_stop = true;
817 	}
818 
819 build_identify:
820 	*p++ = IDENTIFY(tp->flags & ESP_TGT_DISCONNECT, lun);
821 
822 	if (ent->tag[0] && esp->rev == ESP100) {
823 		/* ESP100 lacks select w/atn3 command, use select
824 		 * and stop instead.
825 		 */
826 		select_and_stop = true;
827 	}
828 
829 	if (select_and_stop) {
830 		esp->cmd_bytes_left = cmd->cmd_len;
831 		esp->cmd_bytes_ptr = &cmd->cmnd[0];
832 
833 		if (ent->tag[0]) {
834 			for (i = esp->msg_out_len - 1;
835 			     i >= 0; i--)
836 				esp->msg_out[i + 2] = esp->msg_out[i];
837 			esp->msg_out[0] = ent->tag[0];
838 			esp->msg_out[1] = ent->tag[1];
839 			esp->msg_out_len += 2;
840 		}
841 
842 		start_cmd = ESP_CMD_SELAS;
843 		esp->select_state = ESP_SELECT_MSGOUT;
844 	} else {
845 		start_cmd = ESP_CMD_SELA;
846 		if (ent->tag[0]) {
847 			*p++ = ent->tag[0];
848 			*p++ = ent->tag[1];
849 
850 			start_cmd = ESP_CMD_SA3;
851 		}
852 
853 		for (i = 0; i < cmd->cmd_len; i++)
854 			*p++ = cmd->cmnd[i];
855 
856 		esp->select_state = ESP_SELECT_BASIC;
857 	}
858 	val = tgt;
859 	if (esp->rev == FASHME)
860 		val |= ESP_BUSID_RESELID | ESP_BUSID_CTR32BIT;
861 	esp_write8(val, ESP_BUSID);
862 
863 	esp_write_tgt_sync(esp, tgt);
864 	esp_write_tgt_config3(esp, tgt);
865 
866 	val = (p - esp->command_block);
867 
868 	if (esp_debug & ESP_DEBUG_SCSICMD) {
869 		printk("ESP: tgt[%d] lun[%d] scsi_cmd [ ", tgt, lun);
870 		for (i = 0; i < cmd->cmd_len; i++)
871 			printk("%02x ", cmd->cmnd[i]);
872 		printk("]\n");
873 	}
874 
875 	esp_send_dma_cmd(esp, val, 16, start_cmd);
876 }
877 
esp_get_ent(struct esp * esp)878 static struct esp_cmd_entry *esp_get_ent(struct esp *esp)
879 {
880 	struct list_head *head = &esp->esp_cmd_pool;
881 	struct esp_cmd_entry *ret;
882 
883 	if (list_empty(head)) {
884 		ret = kzalloc(sizeof(struct esp_cmd_entry), GFP_ATOMIC);
885 	} else {
886 		ret = list_entry(head->next, struct esp_cmd_entry, list);
887 		list_del(&ret->list);
888 		memset(ret, 0, sizeof(*ret));
889 	}
890 	return ret;
891 }
892 
esp_put_ent(struct esp * esp,struct esp_cmd_entry * ent)893 static void esp_put_ent(struct esp *esp, struct esp_cmd_entry *ent)
894 {
895 	list_add(&ent->list, &esp->esp_cmd_pool);
896 }
897 
esp_cmd_is_done(struct esp * esp,struct esp_cmd_entry * ent,struct scsi_cmnd * cmd,unsigned char host_byte)898 static void esp_cmd_is_done(struct esp *esp, struct esp_cmd_entry *ent,
899 			    struct scsi_cmnd *cmd, unsigned char host_byte)
900 {
901 	struct scsi_device *dev = cmd->device;
902 	int tgt = dev->id;
903 	int lun = dev->lun;
904 
905 	esp->active_cmd = NULL;
906 	esp_unmap_dma(esp, cmd);
907 	esp_free_lun_tag(ent, dev->hostdata);
908 	cmd->result = 0;
909 	set_host_byte(cmd, host_byte);
910 	if (host_byte == DID_OK)
911 		set_status_byte(cmd, ent->status);
912 
913 	if (ent->eh_done) {
914 		complete(ent->eh_done);
915 		ent->eh_done = NULL;
916 	}
917 
918 	if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
919 		esp_unmap_sense(esp, ent);
920 
921 		/* Restore the message/status bytes to what we actually
922 		 * saw originally.  Also, report that we are providing
923 		 * the sense data.
924 		 */
925 		cmd->result = SAM_STAT_CHECK_CONDITION;
926 
927 		ent->flags &= ~ESP_CMD_FLAG_AUTOSENSE;
928 		if (esp_debug & ESP_DEBUG_AUTOSENSE) {
929 			int i;
930 
931 			printk("esp%d: tgt[%d] lun[%d] AUTO SENSE[ ",
932 			       esp->host->unique_id, tgt, lun);
933 			for (i = 0; i < 18; i++)
934 				printk("%02x ", cmd->sense_buffer[i]);
935 			printk("]\n");
936 		}
937 	}
938 
939 	scsi_done(cmd);
940 
941 	list_del(&ent->list);
942 	esp_put_ent(esp, ent);
943 
944 	esp_maybe_execute_command(esp);
945 }
946 
esp_event_queue_full(struct esp * esp,struct esp_cmd_entry * ent)947 static void esp_event_queue_full(struct esp *esp, struct esp_cmd_entry *ent)
948 {
949 	struct scsi_device *dev = ent->cmd->device;
950 	struct esp_lun_data *lp = dev->hostdata;
951 
952 	scsi_track_queue_full(dev, lp->num_tagged - 1);
953 }
954 
esp_queuecommand_lck(struct scsi_cmnd * cmd)955 static int esp_queuecommand_lck(struct scsi_cmnd *cmd)
956 {
957 	struct scsi_device *dev = cmd->device;
958 	struct esp *esp = shost_priv(dev->host);
959 	struct esp_cmd_priv *spriv;
960 	struct esp_cmd_entry *ent;
961 
962 	ent = esp_get_ent(esp);
963 	if (!ent)
964 		return SCSI_MLQUEUE_HOST_BUSY;
965 
966 	ent->cmd = cmd;
967 
968 	spriv = ESP_CMD_PRIV(cmd);
969 	spriv->num_sg = 0;
970 
971 	list_add_tail(&ent->list, &esp->queued_cmds);
972 
973 	esp_maybe_execute_command(esp);
974 
975 	return 0;
976 }
977 
DEF_SCSI_QCMD(esp_queuecommand)978 static DEF_SCSI_QCMD(esp_queuecommand)
979 
980 static int esp_check_gross_error(struct esp *esp)
981 {
982 	if (esp->sreg & ESP_STAT_SPAM) {
983 		/* Gross Error, could be one of:
984 		 * - top of fifo overwritten
985 		 * - top of command register overwritten
986 		 * - DMA programmed with wrong direction
987 		 * - improper phase change
988 		 */
989 		shost_printk(KERN_ERR, esp->host,
990 			     "Gross error sreg[%02x]\n", esp->sreg);
991 		/* XXX Reset the chip. XXX */
992 		return 1;
993 	}
994 	return 0;
995 }
996 
esp_check_spur_intr(struct esp * esp)997 static int esp_check_spur_intr(struct esp *esp)
998 {
999 	switch (esp->rev) {
1000 	case ESP100:
1001 	case ESP100A:
1002 		/* The interrupt pending bit of the status register cannot
1003 		 * be trusted on these revisions.
1004 		 */
1005 		esp->sreg &= ~ESP_STAT_INTR;
1006 		break;
1007 
1008 	default:
1009 		if (!(esp->sreg & ESP_STAT_INTR)) {
1010 			if (esp->ireg & ESP_INTR_SR)
1011 				return 1;
1012 
1013 			/* If the DMA is indicating interrupt pending and the
1014 			 * ESP is not, the only possibility is a DMA error.
1015 			 */
1016 			if (!esp->ops->dma_error(esp)) {
1017 				shost_printk(KERN_ERR, esp->host,
1018 					     "Spurious irq, sreg=%02x.\n",
1019 					     esp->sreg);
1020 				return -1;
1021 			}
1022 
1023 			shost_printk(KERN_ERR, esp->host, "DMA error\n");
1024 
1025 			/* XXX Reset the chip. XXX */
1026 			return -1;
1027 		}
1028 		break;
1029 	}
1030 
1031 	return 0;
1032 }
1033 
esp_schedule_reset(struct esp * esp)1034 static void esp_schedule_reset(struct esp *esp)
1035 {
1036 	esp_log_reset("esp_schedule_reset() from %ps\n",
1037 		      __builtin_return_address(0));
1038 	esp->flags |= ESP_FLAG_RESETTING;
1039 	esp_event(esp, ESP_EVENT_RESET);
1040 }
1041 
1042 /* In order to avoid having to add a special half-reconnected state
1043  * into the driver we just sit here and poll through the rest of
1044  * the reselection process to get the tag message bytes.
1045  */
esp_reconnect_with_tag(struct esp * esp,struct esp_lun_data * lp)1046 static struct esp_cmd_entry *esp_reconnect_with_tag(struct esp *esp,
1047 						    struct esp_lun_data *lp)
1048 {
1049 	struct esp_cmd_entry *ent;
1050 	int i;
1051 
1052 	if (!lp->num_tagged) {
1053 		shost_printk(KERN_ERR, esp->host,
1054 			     "Reconnect w/num_tagged==0\n");
1055 		return NULL;
1056 	}
1057 
1058 	esp_log_reconnect("reconnect tag, ");
1059 
1060 	for (i = 0; i < ESP_QUICKIRQ_LIMIT; i++) {
1061 		if (esp->ops->irq_pending(esp))
1062 			break;
1063 	}
1064 	if (i == ESP_QUICKIRQ_LIMIT) {
1065 		shost_printk(KERN_ERR, esp->host,
1066 			     "Reconnect IRQ1 timeout\n");
1067 		return NULL;
1068 	}
1069 
1070 	esp->sreg = esp_read8(ESP_STATUS);
1071 	esp->ireg = esp_read8(ESP_INTRPT);
1072 
1073 	esp_log_reconnect("IRQ(%d:%x:%x), ",
1074 			  i, esp->ireg, esp->sreg);
1075 
1076 	if (esp->ireg & ESP_INTR_DC) {
1077 		shost_printk(KERN_ERR, esp->host,
1078 			     "Reconnect, got disconnect.\n");
1079 		return NULL;
1080 	}
1081 
1082 	if ((esp->sreg & ESP_STAT_PMASK) != ESP_MIP) {
1083 		shost_printk(KERN_ERR, esp->host,
1084 			     "Reconnect, not MIP sreg[%02x].\n", esp->sreg);
1085 		return NULL;
1086 	}
1087 
1088 	/* DMA in the tag bytes... */
1089 	esp->command_block[0] = 0xff;
1090 	esp->command_block[1] = 0xff;
1091 	esp->ops->send_dma_cmd(esp, esp->command_block_dma,
1092 			       2, 2, 1, ESP_CMD_DMA | ESP_CMD_TI);
1093 
1094 	/* ACK the message.  */
1095 	scsi_esp_cmd(esp, ESP_CMD_MOK);
1096 
1097 	for (i = 0; i < ESP_RESELECT_TAG_LIMIT; i++) {
1098 		if (esp->ops->irq_pending(esp)) {
1099 			esp->sreg = esp_read8(ESP_STATUS);
1100 			esp->ireg = esp_read8(ESP_INTRPT);
1101 			if (esp->ireg & ESP_INTR_FDONE)
1102 				break;
1103 		}
1104 		udelay(1);
1105 	}
1106 	if (i == ESP_RESELECT_TAG_LIMIT) {
1107 		shost_printk(KERN_ERR, esp->host, "Reconnect IRQ2 timeout\n");
1108 		return NULL;
1109 	}
1110 	esp->ops->dma_drain(esp);
1111 	esp->ops->dma_invalidate(esp);
1112 
1113 	esp_log_reconnect("IRQ2(%d:%x:%x) tag[%x:%x]\n",
1114 			  i, esp->ireg, esp->sreg,
1115 			  esp->command_block[0],
1116 			  esp->command_block[1]);
1117 
1118 	if (esp->command_block[0] < SIMPLE_QUEUE_TAG ||
1119 	    esp->command_block[0] > ORDERED_QUEUE_TAG) {
1120 		shost_printk(KERN_ERR, esp->host,
1121 			     "Reconnect, bad tag type %02x.\n",
1122 			     esp->command_block[0]);
1123 		return NULL;
1124 	}
1125 
1126 	ent = lp->tagged_cmds[esp->command_block[1]];
1127 	if (!ent) {
1128 		shost_printk(KERN_ERR, esp->host,
1129 			     "Reconnect, no entry for tag %02x.\n",
1130 			     esp->command_block[1]);
1131 		return NULL;
1132 	}
1133 
1134 	return ent;
1135 }
1136 
esp_reconnect(struct esp * esp)1137 static int esp_reconnect(struct esp *esp)
1138 {
1139 	struct esp_cmd_entry *ent;
1140 	struct esp_target_data *tp;
1141 	struct esp_lun_data *lp;
1142 	struct scsi_device *dev;
1143 	int target, lun;
1144 
1145 	BUG_ON(esp->active_cmd);
1146 	if (esp->rev == FASHME) {
1147 		/* FASHME puts the target and lun numbers directly
1148 		 * into the fifo.
1149 		 */
1150 		target = esp->fifo[0];
1151 		lun = esp->fifo[1] & 0x7;
1152 	} else {
1153 		u8 bits = esp_read8(ESP_FDATA);
1154 
1155 		/* Older chips put the lun directly into the fifo, but
1156 		 * the target is given as a sample of the arbitration
1157 		 * lines on the bus at reselection time.  So we should
1158 		 * see the ID of the ESP and the one reconnecting target
1159 		 * set in the bitmap.
1160 		 */
1161 		if (!(bits & esp->scsi_id_mask))
1162 			goto do_reset;
1163 		bits &= ~esp->scsi_id_mask;
1164 		if (!bits || (bits & (bits - 1)))
1165 			goto do_reset;
1166 
1167 		target = ffs(bits) - 1;
1168 		lun = (esp_read8(ESP_FDATA) & 0x7);
1169 
1170 		scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1171 		if (esp->rev == ESP100) {
1172 			u8 ireg = esp_read8(ESP_INTRPT);
1173 			/* This chip has a bug during reselection that can
1174 			 * cause a spurious illegal-command interrupt, which
1175 			 * we simply ACK here.  Another possibility is a bus
1176 			 * reset so we must check for that.
1177 			 */
1178 			if (ireg & ESP_INTR_SR)
1179 				goto do_reset;
1180 		}
1181 		scsi_esp_cmd(esp, ESP_CMD_NULL);
1182 	}
1183 
1184 	esp_write_tgt_sync(esp, target);
1185 	esp_write_tgt_config3(esp, target);
1186 
1187 	scsi_esp_cmd(esp, ESP_CMD_MOK);
1188 
1189 	if (esp->rev == FASHME)
1190 		esp_write8(target | ESP_BUSID_RESELID | ESP_BUSID_CTR32BIT,
1191 			   ESP_BUSID);
1192 
1193 	tp = &esp->target[target];
1194 	dev = __scsi_device_lookup_by_target(tp->starget, lun);
1195 	if (!dev) {
1196 		shost_printk(KERN_ERR, esp->host,
1197 			     "Reconnect, no lp tgt[%u] lun[%u]\n",
1198 			     target, lun);
1199 		goto do_reset;
1200 	}
1201 	lp = dev->hostdata;
1202 
1203 	ent = lp->non_tagged_cmd;
1204 	if (!ent) {
1205 		ent = esp_reconnect_with_tag(esp, lp);
1206 		if (!ent)
1207 			goto do_reset;
1208 	}
1209 
1210 	esp->active_cmd = ent;
1211 
1212 	esp_event(esp, ESP_EVENT_CHECK_PHASE);
1213 	esp_restore_pointers(esp, ent);
1214 	esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1215 	return 1;
1216 
1217 do_reset:
1218 	esp_schedule_reset(esp);
1219 	return 0;
1220 }
1221 
esp_finish_select(struct esp * esp)1222 static int esp_finish_select(struct esp *esp)
1223 {
1224 	struct esp_cmd_entry *ent;
1225 	struct scsi_cmnd *cmd;
1226 
1227 	/* No longer selecting.  */
1228 	esp->select_state = ESP_SELECT_NONE;
1229 
1230 	esp->seqreg = esp_read8(ESP_SSTEP) & ESP_STEP_VBITS;
1231 	ent = esp->active_cmd;
1232 	cmd = ent->cmd;
1233 
1234 	if (esp->ops->dma_error(esp)) {
1235 		/* If we see a DMA error during or as a result of selection,
1236 		 * all bets are off.
1237 		 */
1238 		esp_schedule_reset(esp);
1239 		esp_cmd_is_done(esp, ent, cmd, DID_ERROR);
1240 		return 0;
1241 	}
1242 
1243 	esp->ops->dma_invalidate(esp);
1244 
1245 	if (esp->ireg == (ESP_INTR_RSEL | ESP_INTR_FDONE)) {
1246 		struct esp_target_data *tp = &esp->target[cmd->device->id];
1247 
1248 		/* Carefully back out of the selection attempt.  Release
1249 		 * resources (such as DMA mapping & TAG) and reset state (such
1250 		 * as message out and command delivery variables).
1251 		 */
1252 		if (!(ent->flags & ESP_CMD_FLAG_AUTOSENSE)) {
1253 			esp_unmap_dma(esp, cmd);
1254 			esp_free_lun_tag(ent, cmd->device->hostdata);
1255 			tp->flags &= ~(ESP_TGT_NEGO_SYNC | ESP_TGT_NEGO_WIDE);
1256 			esp->cmd_bytes_ptr = NULL;
1257 			esp->cmd_bytes_left = 0;
1258 		} else {
1259 			esp_unmap_sense(esp, ent);
1260 		}
1261 
1262 		/* Now that the state is unwound properly, put back onto
1263 		 * the issue queue.  This command is no longer active.
1264 		 */
1265 		list_move(&ent->list, &esp->queued_cmds);
1266 		esp->active_cmd = NULL;
1267 
1268 		/* Return value ignored by caller, it directly invokes
1269 		 * esp_reconnect().
1270 		 */
1271 		return 0;
1272 	}
1273 
1274 	if (esp->ireg == ESP_INTR_DC) {
1275 		struct scsi_device *dev = cmd->device;
1276 
1277 		/* Disconnect.  Make sure we re-negotiate sync and
1278 		 * wide parameters if this target starts responding
1279 		 * again in the future.
1280 		 */
1281 		esp->target[dev->id].flags |= ESP_TGT_CHECK_NEGO;
1282 
1283 		scsi_esp_cmd(esp, ESP_CMD_ESEL);
1284 		esp_cmd_is_done(esp, ent, cmd, DID_BAD_TARGET);
1285 		return 1;
1286 	}
1287 
1288 	if (esp->ireg == (ESP_INTR_FDONE | ESP_INTR_BSERV)) {
1289 		/* Selection successful.  On pre-FAST chips we have
1290 		 * to do a NOP and possibly clean out the FIFO.
1291 		 */
1292 		if (esp->rev <= ESP236) {
1293 			int fcnt = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;
1294 
1295 			scsi_esp_cmd(esp, ESP_CMD_NULL);
1296 
1297 			if (!fcnt &&
1298 			    (!esp->prev_soff ||
1299 			     ((esp->sreg & ESP_STAT_PMASK) != ESP_DIP)))
1300 				esp_flush_fifo(esp);
1301 		}
1302 
1303 		/* If we are doing a Select And Stop command, negotiation, etc.
1304 		 * we'll do the right thing as we transition to the next phase.
1305 		 */
1306 		esp_event(esp, ESP_EVENT_CHECK_PHASE);
1307 		return 0;
1308 	}
1309 
1310 	shost_printk(KERN_INFO, esp->host,
1311 		     "Unexpected selection completion ireg[%x]\n", esp->ireg);
1312 	esp_schedule_reset(esp);
1313 	return 0;
1314 }
1315 
esp_data_bytes_sent(struct esp * esp,struct esp_cmd_entry * ent,struct scsi_cmnd * cmd)1316 static int esp_data_bytes_sent(struct esp *esp, struct esp_cmd_entry *ent,
1317 			       struct scsi_cmnd *cmd)
1318 {
1319 	int fifo_cnt, ecount, bytes_sent, flush_fifo;
1320 
1321 	fifo_cnt = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;
1322 	if (esp->prev_cfg3 & ESP_CONFIG3_EWIDE)
1323 		fifo_cnt <<= 1;
1324 
1325 	ecount = 0;
1326 	if (!(esp->sreg & ESP_STAT_TCNT)) {
1327 		ecount = ((unsigned int)esp_read8(ESP_TCLOW) |
1328 			  (((unsigned int)esp_read8(ESP_TCMED)) << 8));
1329 		if (esp->rev == FASHME)
1330 			ecount |= ((unsigned int)esp_read8(FAS_RLO)) << 16;
1331 		if (esp->rev == PCSCSI && (esp->config2 & ESP_CONFIG2_FENAB))
1332 			ecount |= ((unsigned int)esp_read8(ESP_TCHI)) << 16;
1333 	}
1334 
1335 	bytes_sent = esp->data_dma_len;
1336 	bytes_sent -= ecount;
1337 	bytes_sent -= esp->send_cmd_residual;
1338 
1339 	/*
1340 	 * The am53c974 has a DMA 'peculiarity'. The doc states:
1341 	 * In some odd byte conditions, one residual byte will
1342 	 * be left in the SCSI FIFO, and the FIFO Flags will
1343 	 * never count to '0 '. When this happens, the residual
1344 	 * byte should be retrieved via PIO following completion
1345 	 * of the BLAST operation.
1346 	 */
1347 	if (fifo_cnt == 1 && ent->flags & ESP_CMD_FLAG_RESIDUAL) {
1348 		size_t count = 1;
1349 		size_t offset = bytes_sent;
1350 		u8 bval = esp_read8(ESP_FDATA);
1351 
1352 		if (ent->flags & ESP_CMD_FLAG_AUTOSENSE)
1353 			ent->sense_ptr[bytes_sent] = bval;
1354 		else {
1355 			struct esp_cmd_priv *p = ESP_CMD_PRIV(cmd);
1356 			u8 *ptr;
1357 
1358 			ptr = scsi_kmap_atomic_sg(p->cur_sg, p->num_sg,
1359 						  &offset, &count);
1360 			if (likely(ptr)) {
1361 				*(ptr + offset) = bval;
1362 				scsi_kunmap_atomic_sg(ptr);
1363 			}
1364 		}
1365 		bytes_sent += fifo_cnt;
1366 		ent->flags &= ~ESP_CMD_FLAG_RESIDUAL;
1367 	}
1368 	if (!(ent->flags & ESP_CMD_FLAG_WRITE))
1369 		bytes_sent -= fifo_cnt;
1370 
1371 	flush_fifo = 0;
1372 	if (!esp->prev_soff) {
1373 		/* Synchronous data transfer, always flush fifo. */
1374 		flush_fifo = 1;
1375 	} else {
1376 		if (esp->rev == ESP100) {
1377 			u32 fflags, phase;
1378 
1379 			/* ESP100 has a chip bug where in the synchronous data
1380 			 * phase it can mistake a final long REQ pulse from the
1381 			 * target as an extra data byte.  Fun.
1382 			 *
1383 			 * To detect this case we resample the status register
1384 			 * and fifo flags.  If we're still in a data phase and
1385 			 * we see spurious chunks in the fifo, we return error
1386 			 * to the caller which should reset and set things up
1387 			 * such that we only try future transfers to this
1388 			 * target in synchronous mode.
1389 			 */
1390 			esp->sreg = esp_read8(ESP_STATUS);
1391 			phase = esp->sreg & ESP_STAT_PMASK;
1392 			fflags = esp_read8(ESP_FFLAGS);
1393 
1394 			if ((phase == ESP_DOP &&
1395 			     (fflags & ESP_FF_ONOTZERO)) ||
1396 			    (phase == ESP_DIP &&
1397 			     (fflags & ESP_FF_FBYTES)))
1398 				return -1;
1399 		}
1400 		if (!(ent->flags & ESP_CMD_FLAG_WRITE))
1401 			flush_fifo = 1;
1402 	}
1403 
1404 	if (flush_fifo)
1405 		esp_flush_fifo(esp);
1406 
1407 	return bytes_sent;
1408 }
1409 
esp_setsync(struct esp * esp,struct esp_target_data * tp,u8 scsi_period,u8 scsi_offset,u8 esp_stp,u8 esp_soff)1410 static void esp_setsync(struct esp *esp, struct esp_target_data *tp,
1411 			u8 scsi_period, u8 scsi_offset,
1412 			u8 esp_stp, u8 esp_soff)
1413 {
1414 	spi_period(tp->starget) = scsi_period;
1415 	spi_offset(tp->starget) = scsi_offset;
1416 	spi_width(tp->starget) = (tp->flags & ESP_TGT_WIDE) ? 1 : 0;
1417 
1418 	if (esp_soff) {
1419 		esp_stp &= 0x1f;
1420 		esp_soff |= esp->radelay;
1421 		if (esp->rev >= FAS236) {
1422 			u8 bit = ESP_CONFIG3_FSCSI;
1423 			if (esp->rev >= FAS100A)
1424 				bit = ESP_CONFIG3_FAST;
1425 
1426 			if (scsi_period < 50) {
1427 				if (esp->rev == FASHME)
1428 					esp_soff &= ~esp->radelay;
1429 				tp->esp_config3 |= bit;
1430 			} else {
1431 				tp->esp_config3 &= ~bit;
1432 			}
1433 			esp->prev_cfg3 = tp->esp_config3;
1434 			esp_write8(esp->prev_cfg3, ESP_CFG3);
1435 		}
1436 	}
1437 
1438 	tp->esp_period = esp->prev_stp = esp_stp;
1439 	tp->esp_offset = esp->prev_soff = esp_soff;
1440 
1441 	esp_write8(esp_soff, ESP_SOFF);
1442 	esp_write8(esp_stp, ESP_STP);
1443 
1444 	tp->flags &= ~(ESP_TGT_NEGO_SYNC | ESP_TGT_CHECK_NEGO);
1445 
1446 	spi_display_xfer_agreement(tp->starget);
1447 }
1448 
esp_msgin_reject(struct esp * esp)1449 static void esp_msgin_reject(struct esp *esp)
1450 {
1451 	struct esp_cmd_entry *ent = esp->active_cmd;
1452 	struct scsi_cmnd *cmd = ent->cmd;
1453 	struct esp_target_data *tp;
1454 	int tgt;
1455 
1456 	tgt = cmd->device->id;
1457 	tp = &esp->target[tgt];
1458 
1459 	if (tp->flags & ESP_TGT_NEGO_WIDE) {
1460 		tp->flags &= ~(ESP_TGT_NEGO_WIDE | ESP_TGT_WIDE);
1461 
1462 		if (!esp_need_to_nego_sync(tp)) {
1463 			tp->flags &= ~ESP_TGT_CHECK_NEGO;
1464 			scsi_esp_cmd(esp, ESP_CMD_RATN);
1465 		} else {
1466 			esp->msg_out_len =
1467 				spi_populate_sync_msg(&esp->msg_out[0],
1468 						      tp->nego_goal_period,
1469 						      tp->nego_goal_offset);
1470 			tp->flags |= ESP_TGT_NEGO_SYNC;
1471 			scsi_esp_cmd(esp, ESP_CMD_SATN);
1472 		}
1473 		return;
1474 	}
1475 
1476 	if (tp->flags & ESP_TGT_NEGO_SYNC) {
1477 		tp->flags &= ~(ESP_TGT_NEGO_SYNC | ESP_TGT_CHECK_NEGO);
1478 		tp->esp_period = 0;
1479 		tp->esp_offset = 0;
1480 		esp_setsync(esp, tp, 0, 0, 0, 0);
1481 		scsi_esp_cmd(esp, ESP_CMD_RATN);
1482 		return;
1483 	}
1484 
1485 	shost_printk(KERN_INFO, esp->host, "Unexpected MESSAGE REJECT\n");
1486 	esp_schedule_reset(esp);
1487 }
1488 
esp_msgin_sdtr(struct esp * esp,struct esp_target_data * tp)1489 static void esp_msgin_sdtr(struct esp *esp, struct esp_target_data *tp)
1490 {
1491 	u8 period = esp->msg_in[3];
1492 	u8 offset = esp->msg_in[4];
1493 	u8 stp;
1494 
1495 	if (!(tp->flags & ESP_TGT_NEGO_SYNC))
1496 		goto do_reject;
1497 
1498 	if (offset > 15)
1499 		goto do_reject;
1500 
1501 	if (offset) {
1502 		int one_clock;
1503 
1504 		if (period > esp->max_period) {
1505 			period = offset = 0;
1506 			goto do_sdtr;
1507 		}
1508 		if (period < esp->min_period)
1509 			goto do_reject;
1510 
1511 		one_clock = esp->ccycle / 1000;
1512 		stp = DIV_ROUND_UP(period << 2, one_clock);
1513 		if (stp && esp->rev >= FAS236) {
1514 			if (stp >= 50)
1515 				stp--;
1516 		}
1517 	} else {
1518 		stp = 0;
1519 	}
1520 
1521 	esp_setsync(esp, tp, period, offset, stp, offset);
1522 	return;
1523 
1524 do_reject:
1525 	esp->msg_out[0] = MESSAGE_REJECT;
1526 	esp->msg_out_len = 1;
1527 	scsi_esp_cmd(esp, ESP_CMD_SATN);
1528 	return;
1529 
1530 do_sdtr:
1531 	tp->nego_goal_period = period;
1532 	tp->nego_goal_offset = offset;
1533 	esp->msg_out_len =
1534 		spi_populate_sync_msg(&esp->msg_out[0],
1535 				      tp->nego_goal_period,
1536 				      tp->nego_goal_offset);
1537 	scsi_esp_cmd(esp, ESP_CMD_SATN);
1538 }
1539 
esp_msgin_wdtr(struct esp * esp,struct esp_target_data * tp)1540 static void esp_msgin_wdtr(struct esp *esp, struct esp_target_data *tp)
1541 {
1542 	int size = 8 << esp->msg_in[3];
1543 	u8 cfg3;
1544 
1545 	if (esp->rev != FASHME)
1546 		goto do_reject;
1547 
1548 	if (size != 8 && size != 16)
1549 		goto do_reject;
1550 
1551 	if (!(tp->flags & ESP_TGT_NEGO_WIDE))
1552 		goto do_reject;
1553 
1554 	cfg3 = tp->esp_config3;
1555 	if (size == 16) {
1556 		tp->flags |= ESP_TGT_WIDE;
1557 		cfg3 |= ESP_CONFIG3_EWIDE;
1558 	} else {
1559 		tp->flags &= ~ESP_TGT_WIDE;
1560 		cfg3 &= ~ESP_CONFIG3_EWIDE;
1561 	}
1562 	tp->esp_config3 = cfg3;
1563 	esp->prev_cfg3 = cfg3;
1564 	esp_write8(cfg3, ESP_CFG3);
1565 
1566 	tp->flags &= ~ESP_TGT_NEGO_WIDE;
1567 
1568 	spi_period(tp->starget) = 0;
1569 	spi_offset(tp->starget) = 0;
1570 	if (!esp_need_to_nego_sync(tp)) {
1571 		tp->flags &= ~ESP_TGT_CHECK_NEGO;
1572 		scsi_esp_cmd(esp, ESP_CMD_RATN);
1573 	} else {
1574 		esp->msg_out_len =
1575 			spi_populate_sync_msg(&esp->msg_out[0],
1576 					      tp->nego_goal_period,
1577 					      tp->nego_goal_offset);
1578 		tp->flags |= ESP_TGT_NEGO_SYNC;
1579 		scsi_esp_cmd(esp, ESP_CMD_SATN);
1580 	}
1581 	return;
1582 
1583 do_reject:
1584 	esp->msg_out[0] = MESSAGE_REJECT;
1585 	esp->msg_out_len = 1;
1586 	scsi_esp_cmd(esp, ESP_CMD_SATN);
1587 }
1588 
esp_msgin_extended(struct esp * esp)1589 static void esp_msgin_extended(struct esp *esp)
1590 {
1591 	struct esp_cmd_entry *ent = esp->active_cmd;
1592 	struct scsi_cmnd *cmd = ent->cmd;
1593 	struct esp_target_data *tp;
1594 	int tgt = cmd->device->id;
1595 
1596 	tp = &esp->target[tgt];
1597 	if (esp->msg_in[2] == EXTENDED_SDTR) {
1598 		esp_msgin_sdtr(esp, tp);
1599 		return;
1600 	}
1601 	if (esp->msg_in[2] == EXTENDED_WDTR) {
1602 		esp_msgin_wdtr(esp, tp);
1603 		return;
1604 	}
1605 
1606 	shost_printk(KERN_INFO, esp->host,
1607 		     "Unexpected extended msg type %x\n", esp->msg_in[2]);
1608 
1609 	esp->msg_out[0] = MESSAGE_REJECT;
1610 	esp->msg_out_len = 1;
1611 	scsi_esp_cmd(esp, ESP_CMD_SATN);
1612 }
1613 
1614 /* Analyze msgin bytes received from target so far.  Return non-zero
1615  * if there are more bytes needed to complete the message.
1616  */
esp_msgin_process(struct esp * esp)1617 static int esp_msgin_process(struct esp *esp)
1618 {
1619 	u8 msg0 = esp->msg_in[0];
1620 	int len = esp->msg_in_len;
1621 
1622 	if (msg0 & 0x80) {
1623 		/* Identify */
1624 		shost_printk(KERN_INFO, esp->host,
1625 			     "Unexpected msgin identify\n");
1626 		return 0;
1627 	}
1628 
1629 	switch (msg0) {
1630 	case EXTENDED_MESSAGE:
1631 		if (len == 1)
1632 			return 1;
1633 		if (len < esp->msg_in[1] + 2)
1634 			return 1;
1635 		esp_msgin_extended(esp);
1636 		return 0;
1637 
1638 	case IGNORE_WIDE_RESIDUE: {
1639 		struct esp_cmd_entry *ent;
1640 		struct esp_cmd_priv *spriv;
1641 		if (len == 1)
1642 			return 1;
1643 
1644 		if (esp->msg_in[1] != 1)
1645 			goto do_reject;
1646 
1647 		ent = esp->active_cmd;
1648 		spriv = ESP_CMD_PRIV(ent->cmd);
1649 
1650 		if (spriv->cur_residue == sg_dma_len(spriv->cur_sg)) {
1651 			spriv->cur_sg = spriv->prv_sg;
1652 			spriv->cur_residue = 1;
1653 		} else
1654 			spriv->cur_residue++;
1655 		spriv->tot_residue++;
1656 		return 0;
1657 	}
1658 	case NOP:
1659 		return 0;
1660 	case RESTORE_POINTERS:
1661 		esp_restore_pointers(esp, esp->active_cmd);
1662 		return 0;
1663 	case SAVE_POINTERS:
1664 		esp_save_pointers(esp, esp->active_cmd);
1665 		return 0;
1666 
1667 	case COMMAND_COMPLETE:
1668 	case DISCONNECT: {
1669 		struct esp_cmd_entry *ent = esp->active_cmd;
1670 
1671 		ent->message = msg0;
1672 		esp_event(esp, ESP_EVENT_FREE_BUS);
1673 		esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1674 		return 0;
1675 	}
1676 	case MESSAGE_REJECT:
1677 		esp_msgin_reject(esp);
1678 		return 0;
1679 
1680 	default:
1681 	do_reject:
1682 		esp->msg_out[0] = MESSAGE_REJECT;
1683 		esp->msg_out_len = 1;
1684 		scsi_esp_cmd(esp, ESP_CMD_SATN);
1685 		return 0;
1686 	}
1687 }
1688 
esp_process_event(struct esp * esp)1689 static int esp_process_event(struct esp *esp)
1690 {
1691 	int write, i;
1692 
1693 again:
1694 	write = 0;
1695 	esp_log_event("process event %d phase %x\n",
1696 		      esp->event, esp->sreg & ESP_STAT_PMASK);
1697 	switch (esp->event) {
1698 	case ESP_EVENT_CHECK_PHASE:
1699 		switch (esp->sreg & ESP_STAT_PMASK) {
1700 		case ESP_DOP:
1701 			esp_event(esp, ESP_EVENT_DATA_OUT);
1702 			break;
1703 		case ESP_DIP:
1704 			esp_event(esp, ESP_EVENT_DATA_IN);
1705 			break;
1706 		case ESP_STATP:
1707 			esp_flush_fifo(esp);
1708 			scsi_esp_cmd(esp, ESP_CMD_ICCSEQ);
1709 			esp_event(esp, ESP_EVENT_STATUS);
1710 			esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1711 			return 1;
1712 
1713 		case ESP_MOP:
1714 			esp_event(esp, ESP_EVENT_MSGOUT);
1715 			break;
1716 
1717 		case ESP_MIP:
1718 			esp_event(esp, ESP_EVENT_MSGIN);
1719 			break;
1720 
1721 		case ESP_CMDP:
1722 			esp_event(esp, ESP_EVENT_CMD_START);
1723 			break;
1724 
1725 		default:
1726 			shost_printk(KERN_INFO, esp->host,
1727 				     "Unexpected phase, sreg=%02x\n",
1728 				     esp->sreg);
1729 			esp_schedule_reset(esp);
1730 			return 0;
1731 		}
1732 		goto again;
1733 
1734 	case ESP_EVENT_DATA_IN:
1735 		write = 1;
1736 		fallthrough;
1737 
1738 	case ESP_EVENT_DATA_OUT: {
1739 		struct esp_cmd_entry *ent = esp->active_cmd;
1740 		struct scsi_cmnd *cmd = ent->cmd;
1741 		dma_addr_t dma_addr = esp_cur_dma_addr(ent, cmd);
1742 		unsigned int dma_len = esp_cur_dma_len(ent, cmd);
1743 
1744 		if (esp->rev == ESP100)
1745 			scsi_esp_cmd(esp, ESP_CMD_NULL);
1746 
1747 		if (write)
1748 			ent->flags |= ESP_CMD_FLAG_WRITE;
1749 		else
1750 			ent->flags &= ~ESP_CMD_FLAG_WRITE;
1751 
1752 		if (esp->ops->dma_length_limit)
1753 			dma_len = esp->ops->dma_length_limit(esp, dma_addr,
1754 							     dma_len);
1755 		else
1756 			dma_len = esp_dma_length_limit(esp, dma_addr, dma_len);
1757 
1758 		esp->data_dma_len = dma_len;
1759 
1760 		if (!dma_len) {
1761 			shost_printk(KERN_ERR, esp->host,
1762 				     "DMA length is zero!\n");
1763 			shost_printk(KERN_ERR, esp->host,
1764 				     "cur adr[%08llx] len[%08x]\n",
1765 				     (unsigned long long)esp_cur_dma_addr(ent, cmd),
1766 				     esp_cur_dma_len(ent, cmd));
1767 			esp_schedule_reset(esp);
1768 			return 0;
1769 		}
1770 
1771 		esp_log_datastart("start data addr[%08llx] len[%u] write(%d)\n",
1772 				  (unsigned long long)dma_addr, dma_len, write);
1773 
1774 		esp->ops->send_dma_cmd(esp, dma_addr, dma_len, dma_len,
1775 				       write, ESP_CMD_DMA | ESP_CMD_TI);
1776 		esp_event(esp, ESP_EVENT_DATA_DONE);
1777 		break;
1778 	}
1779 	case ESP_EVENT_DATA_DONE: {
1780 		struct esp_cmd_entry *ent = esp->active_cmd;
1781 		struct scsi_cmnd *cmd = ent->cmd;
1782 		int bytes_sent;
1783 
1784 		if (esp->ops->dma_error(esp)) {
1785 			shost_printk(KERN_INFO, esp->host,
1786 				     "data done, DMA error, resetting\n");
1787 			esp_schedule_reset(esp);
1788 			return 0;
1789 		}
1790 
1791 		if (ent->flags & ESP_CMD_FLAG_WRITE) {
1792 			/* XXX parity errors, etc. XXX */
1793 
1794 			esp->ops->dma_drain(esp);
1795 		}
1796 		esp->ops->dma_invalidate(esp);
1797 
1798 		if (esp->ireg != ESP_INTR_BSERV) {
1799 			/* We should always see exactly a bus-service
1800 			 * interrupt at the end of a successful transfer.
1801 			 */
1802 			shost_printk(KERN_INFO, esp->host,
1803 				     "data done, not BSERV, resetting\n");
1804 			esp_schedule_reset(esp);
1805 			return 0;
1806 		}
1807 
1808 		bytes_sent = esp_data_bytes_sent(esp, ent, cmd);
1809 
1810 		esp_log_datadone("data done flgs[%x] sent[%d]\n",
1811 				 ent->flags, bytes_sent);
1812 
1813 		if (bytes_sent < 0) {
1814 			/* XXX force sync mode for this target XXX */
1815 			esp_schedule_reset(esp);
1816 			return 0;
1817 		}
1818 
1819 		esp_advance_dma(esp, ent, cmd, bytes_sent);
1820 		esp_event(esp, ESP_EVENT_CHECK_PHASE);
1821 		goto again;
1822 	}
1823 
1824 	case ESP_EVENT_STATUS: {
1825 		struct esp_cmd_entry *ent = esp->active_cmd;
1826 
1827 		if (esp->ireg & ESP_INTR_FDONE) {
1828 			ent->status = esp_read8(ESP_FDATA);
1829 			ent->message = esp_read8(ESP_FDATA);
1830 			scsi_esp_cmd(esp, ESP_CMD_MOK);
1831 		} else if (esp->ireg == ESP_INTR_BSERV) {
1832 			ent->status = esp_read8(ESP_FDATA);
1833 			ent->message = 0xff;
1834 			esp_event(esp, ESP_EVENT_MSGIN);
1835 			return 0;
1836 		}
1837 
1838 		if (ent->message != COMMAND_COMPLETE) {
1839 			shost_printk(KERN_INFO, esp->host,
1840 				     "Unexpected message %x in status\n",
1841 				     ent->message);
1842 			esp_schedule_reset(esp);
1843 			return 0;
1844 		}
1845 
1846 		esp_event(esp, ESP_EVENT_FREE_BUS);
1847 		esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1848 		break;
1849 	}
1850 	case ESP_EVENT_FREE_BUS: {
1851 		struct esp_cmd_entry *ent = esp->active_cmd;
1852 		struct scsi_cmnd *cmd = ent->cmd;
1853 
1854 		if (ent->message == COMMAND_COMPLETE ||
1855 		    ent->message == DISCONNECT)
1856 			scsi_esp_cmd(esp, ESP_CMD_ESEL);
1857 
1858 		if (ent->message == COMMAND_COMPLETE) {
1859 			esp_log_cmddone("Command done status[%x] message[%x]\n",
1860 					ent->status, ent->message);
1861 			if (ent->status == SAM_STAT_TASK_SET_FULL)
1862 				esp_event_queue_full(esp, ent);
1863 
1864 			if (ent->status == SAM_STAT_CHECK_CONDITION &&
1865 			    !(ent->flags & ESP_CMD_FLAG_AUTOSENSE)) {
1866 				ent->flags |= ESP_CMD_FLAG_AUTOSENSE;
1867 				esp_autosense(esp, ent);
1868 			} else {
1869 				esp_cmd_is_done(esp, ent, cmd, DID_OK);
1870 			}
1871 		} else if (ent->message == DISCONNECT) {
1872 			esp_log_disconnect("Disconnecting tgt[%d] tag[%x:%x]\n",
1873 					   cmd->device->id,
1874 					   ent->tag[0], ent->tag[1]);
1875 
1876 			esp->active_cmd = NULL;
1877 			esp_maybe_execute_command(esp);
1878 		} else {
1879 			shost_printk(KERN_INFO, esp->host,
1880 				     "Unexpected message %x in freebus\n",
1881 				     ent->message);
1882 			esp_schedule_reset(esp);
1883 			return 0;
1884 		}
1885 		if (esp->active_cmd)
1886 			esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1887 		break;
1888 	}
1889 	case ESP_EVENT_MSGOUT: {
1890 		scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1891 
1892 		if (esp_debug & ESP_DEBUG_MSGOUT) {
1893 			int i;
1894 			printk("ESP: Sending message [ ");
1895 			for (i = 0; i < esp->msg_out_len; i++)
1896 				printk("%02x ", esp->msg_out[i]);
1897 			printk("]\n");
1898 		}
1899 
1900 		if (esp->rev == FASHME) {
1901 			int i;
1902 
1903 			/* Always use the fifo.  */
1904 			for (i = 0; i < esp->msg_out_len; i++) {
1905 				esp_write8(esp->msg_out[i], ESP_FDATA);
1906 				esp_write8(0, ESP_FDATA);
1907 			}
1908 			scsi_esp_cmd(esp, ESP_CMD_TI);
1909 		} else {
1910 			if (esp->msg_out_len == 1) {
1911 				esp_write8(esp->msg_out[0], ESP_FDATA);
1912 				scsi_esp_cmd(esp, ESP_CMD_TI);
1913 			} else if (esp->flags & ESP_FLAG_USE_FIFO) {
1914 				for (i = 0; i < esp->msg_out_len; i++)
1915 					esp_write8(esp->msg_out[i], ESP_FDATA);
1916 				scsi_esp_cmd(esp, ESP_CMD_TI);
1917 			} else {
1918 				/* Use DMA. */
1919 				memcpy(esp->command_block,
1920 				       esp->msg_out,
1921 				       esp->msg_out_len);
1922 
1923 				esp->ops->send_dma_cmd(esp,
1924 						       esp->command_block_dma,
1925 						       esp->msg_out_len,
1926 						       esp->msg_out_len,
1927 						       0,
1928 						       ESP_CMD_DMA|ESP_CMD_TI);
1929 			}
1930 		}
1931 		esp_event(esp, ESP_EVENT_MSGOUT_DONE);
1932 		break;
1933 	}
1934 	case ESP_EVENT_MSGOUT_DONE:
1935 		if (esp->rev == FASHME) {
1936 			scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1937 		} else {
1938 			if (esp->msg_out_len > 1)
1939 				esp->ops->dma_invalidate(esp);
1940 
1941 			/* XXX if the chip went into disconnected mode,
1942 			 * we can't run the phase state machine anyway.
1943 			 */
1944 			if (!(esp->ireg & ESP_INTR_DC))
1945 				scsi_esp_cmd(esp, ESP_CMD_NULL);
1946 		}
1947 
1948 		esp->msg_out_len = 0;
1949 
1950 		esp_event(esp, ESP_EVENT_CHECK_PHASE);
1951 		goto again;
1952 	case ESP_EVENT_MSGIN:
1953 		if (esp->ireg & ESP_INTR_BSERV) {
1954 			if (esp->rev == FASHME) {
1955 				if (!(esp_read8(ESP_STATUS2) &
1956 				      ESP_STAT2_FEMPTY))
1957 					scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1958 			} else {
1959 				scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1960 				if (esp->rev == ESP100)
1961 					scsi_esp_cmd(esp, ESP_CMD_NULL);
1962 			}
1963 			scsi_esp_cmd(esp, ESP_CMD_TI);
1964 			esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1965 			return 1;
1966 		}
1967 		if (esp->ireg & ESP_INTR_FDONE) {
1968 			u8 val;
1969 
1970 			if (esp->rev == FASHME)
1971 				val = esp->fifo[0];
1972 			else
1973 				val = esp_read8(ESP_FDATA);
1974 			esp->msg_in[esp->msg_in_len++] = val;
1975 
1976 			esp_log_msgin("Got msgin byte %x\n", val);
1977 
1978 			if (!esp_msgin_process(esp))
1979 				esp->msg_in_len = 0;
1980 
1981 			if (esp->rev == FASHME)
1982 				scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1983 
1984 			scsi_esp_cmd(esp, ESP_CMD_MOK);
1985 
1986 			/* Check whether a bus reset is to be done next */
1987 			if (esp->event == ESP_EVENT_RESET)
1988 				return 0;
1989 
1990 			if (esp->event != ESP_EVENT_FREE_BUS)
1991 				esp_event(esp, ESP_EVENT_CHECK_PHASE);
1992 		} else {
1993 			shost_printk(KERN_INFO, esp->host,
1994 				     "MSGIN neither BSERV not FDON, resetting");
1995 			esp_schedule_reset(esp);
1996 			return 0;
1997 		}
1998 		break;
1999 	case ESP_EVENT_CMD_START:
2000 		memcpy(esp->command_block, esp->cmd_bytes_ptr,
2001 		       esp->cmd_bytes_left);
2002 		esp_send_dma_cmd(esp, esp->cmd_bytes_left, 16, ESP_CMD_TI);
2003 		esp_event(esp, ESP_EVENT_CMD_DONE);
2004 		esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
2005 		break;
2006 	case ESP_EVENT_CMD_DONE:
2007 		esp->ops->dma_invalidate(esp);
2008 		if (esp->ireg & ESP_INTR_BSERV) {
2009 			esp_event(esp, ESP_EVENT_CHECK_PHASE);
2010 			goto again;
2011 		}
2012 		esp_schedule_reset(esp);
2013 		return 0;
2014 
2015 	case ESP_EVENT_RESET:
2016 		scsi_esp_cmd(esp, ESP_CMD_RS);
2017 		break;
2018 
2019 	default:
2020 		shost_printk(KERN_INFO, esp->host,
2021 			     "Unexpected event %x, resetting\n", esp->event);
2022 		esp_schedule_reset(esp);
2023 		return 0;
2024 	}
2025 	return 1;
2026 }
2027 
esp_reset_cleanup_one(struct esp * esp,struct esp_cmd_entry * ent)2028 static void esp_reset_cleanup_one(struct esp *esp, struct esp_cmd_entry *ent)
2029 {
2030 	struct scsi_cmnd *cmd = ent->cmd;
2031 
2032 	esp_unmap_dma(esp, cmd);
2033 	esp_free_lun_tag(ent, cmd->device->hostdata);
2034 	cmd->result = DID_RESET << 16;
2035 
2036 	if (ent->flags & ESP_CMD_FLAG_AUTOSENSE)
2037 		esp_unmap_sense(esp, ent);
2038 
2039 	scsi_done(cmd);
2040 	list_del(&ent->list);
2041 	esp_put_ent(esp, ent);
2042 }
2043 
esp_clear_hold(struct scsi_device * dev,void * data)2044 static void esp_clear_hold(struct scsi_device *dev, void *data)
2045 {
2046 	struct esp_lun_data *lp = dev->hostdata;
2047 
2048 	BUG_ON(lp->num_tagged);
2049 	lp->hold = 0;
2050 }
2051 
esp_reset_cleanup(struct esp * esp)2052 static void esp_reset_cleanup(struct esp *esp)
2053 {
2054 	struct esp_cmd_entry *ent, *tmp;
2055 	int i;
2056 
2057 	list_for_each_entry_safe(ent, tmp, &esp->queued_cmds, list) {
2058 		struct scsi_cmnd *cmd = ent->cmd;
2059 
2060 		list_del(&ent->list);
2061 		cmd->result = DID_RESET << 16;
2062 		scsi_done(cmd);
2063 		esp_put_ent(esp, ent);
2064 	}
2065 
2066 	list_for_each_entry_safe(ent, tmp, &esp->active_cmds, list) {
2067 		if (ent == esp->active_cmd)
2068 			esp->active_cmd = NULL;
2069 		esp_reset_cleanup_one(esp, ent);
2070 	}
2071 
2072 	BUG_ON(esp->active_cmd != NULL);
2073 
2074 	/* Force renegotiation of sync/wide transfers.  */
2075 	for (i = 0; i < ESP_MAX_TARGET; i++) {
2076 		struct esp_target_data *tp = &esp->target[i];
2077 
2078 		tp->esp_period = 0;
2079 		tp->esp_offset = 0;
2080 		tp->esp_config3 &= ~(ESP_CONFIG3_EWIDE |
2081 				     ESP_CONFIG3_FSCSI |
2082 				     ESP_CONFIG3_FAST);
2083 		tp->flags &= ~ESP_TGT_WIDE;
2084 		tp->flags |= ESP_TGT_CHECK_NEGO;
2085 
2086 		if (tp->starget)
2087 			__starget_for_each_device(tp->starget, NULL,
2088 						  esp_clear_hold);
2089 	}
2090 	esp->flags &= ~ESP_FLAG_RESETTING;
2091 }
2092 
2093 /* Runs under host->lock */
__esp_interrupt(struct esp * esp)2094 static void __esp_interrupt(struct esp *esp)
2095 {
2096 	int finish_reset, intr_done;
2097 	u8 phase;
2098 
2099        /*
2100 	* Once INTRPT is read STATUS and SSTEP are cleared.
2101 	*/
2102 	esp->sreg = esp_read8(ESP_STATUS);
2103 	esp->seqreg = esp_read8(ESP_SSTEP);
2104 	esp->ireg = esp_read8(ESP_INTRPT);
2105 
2106 	if (esp->flags & ESP_FLAG_RESETTING) {
2107 		finish_reset = 1;
2108 	} else {
2109 		if (esp_check_gross_error(esp))
2110 			return;
2111 
2112 		finish_reset = esp_check_spur_intr(esp);
2113 		if (finish_reset < 0)
2114 			return;
2115 	}
2116 
2117 	if (esp->ireg & ESP_INTR_SR)
2118 		finish_reset = 1;
2119 
2120 	if (finish_reset) {
2121 		esp_reset_cleanup(esp);
2122 		if (esp->eh_reset) {
2123 			complete(esp->eh_reset);
2124 			esp->eh_reset = NULL;
2125 		}
2126 		return;
2127 	}
2128 
2129 	phase = (esp->sreg & ESP_STAT_PMASK);
2130 	if (esp->rev == FASHME) {
2131 		if (((phase != ESP_DIP && phase != ESP_DOP) &&
2132 		     esp->select_state == ESP_SELECT_NONE &&
2133 		     esp->event != ESP_EVENT_STATUS &&
2134 		     esp->event != ESP_EVENT_DATA_DONE) ||
2135 		    (esp->ireg & ESP_INTR_RSEL)) {
2136 			esp->sreg2 = esp_read8(ESP_STATUS2);
2137 			if (!(esp->sreg2 & ESP_STAT2_FEMPTY) ||
2138 			    (esp->sreg2 & ESP_STAT2_F1BYTE))
2139 				hme_read_fifo(esp);
2140 		}
2141 	}
2142 
2143 	esp_log_intr("intr sreg[%02x] seqreg[%02x] "
2144 		     "sreg2[%02x] ireg[%02x]\n",
2145 		     esp->sreg, esp->seqreg, esp->sreg2, esp->ireg);
2146 
2147 	intr_done = 0;
2148 
2149 	if (esp->ireg & (ESP_INTR_S | ESP_INTR_SATN | ESP_INTR_IC)) {
2150 		shost_printk(KERN_INFO, esp->host,
2151 			     "unexpected IREG %02x\n", esp->ireg);
2152 		if (esp->ireg & ESP_INTR_IC)
2153 			esp_dump_cmd_log(esp);
2154 
2155 		esp_schedule_reset(esp);
2156 	} else {
2157 		if (esp->ireg & ESP_INTR_RSEL) {
2158 			if (esp->active_cmd)
2159 				(void) esp_finish_select(esp);
2160 			intr_done = esp_reconnect(esp);
2161 		} else {
2162 			/* Some combination of FDONE, BSERV, DC. */
2163 			if (esp->select_state != ESP_SELECT_NONE)
2164 				intr_done = esp_finish_select(esp);
2165 		}
2166 	}
2167 	while (!intr_done)
2168 		intr_done = esp_process_event(esp);
2169 }
2170 
scsi_esp_intr(int irq,void * dev_id)2171 irqreturn_t scsi_esp_intr(int irq, void *dev_id)
2172 {
2173 	struct esp *esp = dev_id;
2174 	unsigned long flags;
2175 	irqreturn_t ret;
2176 
2177 	spin_lock_irqsave(esp->host->host_lock, flags);
2178 	ret = IRQ_NONE;
2179 	if (esp->ops->irq_pending(esp)) {
2180 		ret = IRQ_HANDLED;
2181 		for (;;) {
2182 			int i;
2183 
2184 			__esp_interrupt(esp);
2185 			if (!(esp->flags & ESP_FLAG_QUICKIRQ_CHECK))
2186 				break;
2187 			esp->flags &= ~ESP_FLAG_QUICKIRQ_CHECK;
2188 
2189 			for (i = 0; i < ESP_QUICKIRQ_LIMIT; i++) {
2190 				if (esp->ops->irq_pending(esp))
2191 					break;
2192 			}
2193 			if (i == ESP_QUICKIRQ_LIMIT)
2194 				break;
2195 		}
2196 	}
2197 	spin_unlock_irqrestore(esp->host->host_lock, flags);
2198 
2199 	return ret;
2200 }
2201 EXPORT_SYMBOL(scsi_esp_intr);
2202 
esp_get_revision(struct esp * esp)2203 static void esp_get_revision(struct esp *esp)
2204 {
2205 	u8 val;
2206 
2207 	esp->config1 = (ESP_CONFIG1_PENABLE | (esp->scsi_id & 7));
2208 	if (esp->config2 == 0) {
2209 		esp->config2 = (ESP_CONFIG2_SCSI2ENAB | ESP_CONFIG2_REGPARITY);
2210 		esp_write8(esp->config2, ESP_CFG2);
2211 
2212 		val = esp_read8(ESP_CFG2);
2213 		val &= ~ESP_CONFIG2_MAGIC;
2214 
2215 		esp->config2 = 0;
2216 		if (val != (ESP_CONFIG2_SCSI2ENAB | ESP_CONFIG2_REGPARITY)) {
2217 			/*
2218 			 * If what we write to cfg2 does not come back,
2219 			 * cfg2 is not implemented.
2220 			 * Therefore this must be a plain esp100.
2221 			 */
2222 			esp->rev = ESP100;
2223 			return;
2224 		}
2225 	}
2226 
2227 	esp_set_all_config3(esp, 5);
2228 	esp->prev_cfg3 = 5;
2229 	esp_write8(esp->config2, ESP_CFG2);
2230 	esp_write8(0, ESP_CFG3);
2231 	esp_write8(esp->prev_cfg3, ESP_CFG3);
2232 
2233 	val = esp_read8(ESP_CFG3);
2234 	if (val != 5) {
2235 		/* The cfg2 register is implemented, however
2236 		 * cfg3 is not, must be esp100a.
2237 		 */
2238 		esp->rev = ESP100A;
2239 	} else {
2240 		esp_set_all_config3(esp, 0);
2241 		esp->prev_cfg3 = 0;
2242 		esp_write8(esp->prev_cfg3, ESP_CFG3);
2243 
2244 		/* All of cfg{1,2,3} implemented, must be one of
2245 		 * the fas variants, figure out which one.
2246 		 */
2247 		if (esp->cfact == 0 || esp->cfact > ESP_CCF_F5) {
2248 			esp->rev = FAST;
2249 			esp->sync_defp = SYNC_DEFP_FAST;
2250 		} else {
2251 			esp->rev = ESP236;
2252 		}
2253 	}
2254 }
2255 
esp_init_swstate(struct esp * esp)2256 static void esp_init_swstate(struct esp *esp)
2257 {
2258 	int i;
2259 
2260 	INIT_LIST_HEAD(&esp->queued_cmds);
2261 	INIT_LIST_HEAD(&esp->active_cmds);
2262 	INIT_LIST_HEAD(&esp->esp_cmd_pool);
2263 
2264 	/* Start with a clear state, domain validation (via ->slave_configure,
2265 	 * spi_dv_device()) will attempt to enable SYNC, WIDE, and tagged
2266 	 * commands.
2267 	 */
2268 	for (i = 0 ; i < ESP_MAX_TARGET; i++) {
2269 		esp->target[i].flags = 0;
2270 		esp->target[i].nego_goal_period = 0;
2271 		esp->target[i].nego_goal_offset = 0;
2272 		esp->target[i].nego_goal_width = 0;
2273 		esp->target[i].nego_goal_tags = 0;
2274 	}
2275 }
2276 
2277 /* This places the ESP into a known state at boot time. */
esp_bootup_reset(struct esp * esp)2278 static void esp_bootup_reset(struct esp *esp)
2279 {
2280 	u8 val;
2281 
2282 	/* Reset the DMA */
2283 	esp->ops->reset_dma(esp);
2284 
2285 	/* Reset the ESP */
2286 	esp_reset_esp(esp);
2287 
2288 	/* Reset the SCSI bus, but tell ESP not to generate an irq */
2289 	val = esp_read8(ESP_CFG1);
2290 	val |= ESP_CONFIG1_SRRDISAB;
2291 	esp_write8(val, ESP_CFG1);
2292 
2293 	scsi_esp_cmd(esp, ESP_CMD_RS);
2294 	udelay(400);
2295 
2296 	esp_write8(esp->config1, ESP_CFG1);
2297 
2298 	/* Eat any bitrot in the chip and we are done... */
2299 	esp_read8(ESP_INTRPT);
2300 }
2301 
esp_set_clock_params(struct esp * esp)2302 static void esp_set_clock_params(struct esp *esp)
2303 {
2304 	int fhz;
2305 	u8 ccf;
2306 
2307 	/* This is getting messy but it has to be done correctly or else
2308 	 * you get weird behavior all over the place.  We are trying to
2309 	 * basically figure out three pieces of information.
2310 	 *
2311 	 * a) Clock Conversion Factor
2312 	 *
2313 	 *    This is a representation of the input crystal clock frequency
2314 	 *    going into the ESP on this machine.  Any operation whose timing
2315 	 *    is longer than 400ns depends on this value being correct.  For
2316 	 *    example, you'll get blips for arbitration/selection during high
2317 	 *    load or with multiple targets if this is not set correctly.
2318 	 *
2319 	 * b) Selection Time-Out
2320 	 *
2321 	 *    The ESP isn't very bright and will arbitrate for the bus and try
2322 	 *    to select a target forever if you let it.  This value tells the
2323 	 *    ESP when it has taken too long to negotiate and that it should
2324 	 *    interrupt the CPU so we can see what happened.  The value is
2325 	 *    computed as follows (from NCR/Symbios chip docs).
2326 	 *
2327 	 *          (Time Out Period) *  (Input Clock)
2328 	 *    STO = ----------------------------------
2329 	 *          (8192) * (Clock Conversion Factor)
2330 	 *
2331 	 *    We use a time out period of 250ms (ESP_BUS_TIMEOUT).
2332 	 *
2333 	 * c) Imperical constants for synchronous offset and transfer period
2334          *    register values
2335 	 *
2336 	 *    This entails the smallest and largest sync period we could ever
2337 	 *    handle on this ESP.
2338 	 */
2339 	fhz = esp->cfreq;
2340 
2341 	ccf = ((fhz / 1000000) + 4) / 5;
2342 	if (ccf == 1)
2343 		ccf = 2;
2344 
2345 	/* If we can't find anything reasonable, just assume 20MHZ.
2346 	 * This is the clock frequency of the older sun4c's where I've
2347 	 * been unable to find the clock-frequency PROM property.  All
2348 	 * other machines provide useful values it seems.
2349 	 */
2350 	if (fhz <= 5000000 || ccf < 1 || ccf > 8) {
2351 		fhz = 20000000;
2352 		ccf = 4;
2353 	}
2354 
2355 	esp->cfact = (ccf == 8 ? 0 : ccf);
2356 	esp->cfreq = fhz;
2357 	esp->ccycle = ESP_HZ_TO_CYCLE(fhz);
2358 	esp->ctick = ESP_TICK(ccf, esp->ccycle);
2359 	esp->neg_defp = ESP_NEG_DEFP(fhz, ccf);
2360 	esp->sync_defp = SYNC_DEFP_SLOW;
2361 }
2362 
2363 static const char *esp_chip_names[] = {
2364 	"ESP100",
2365 	"ESP100A",
2366 	"ESP236",
2367 	"FAS236",
2368 	"AM53C974",
2369 	"53CF9x-2",
2370 	"FAS100A",
2371 	"FAST",
2372 	"FASHME",
2373 };
2374 
2375 static struct scsi_transport_template *esp_transport_template;
2376 
scsi_esp_register(struct esp * esp)2377 int scsi_esp_register(struct esp *esp)
2378 {
2379 	static int instance;
2380 	int err;
2381 
2382 	if (!esp->num_tags)
2383 		esp->num_tags = ESP_DEFAULT_TAGS;
2384 	esp->host->transportt = esp_transport_template;
2385 	esp->host->max_lun = ESP_MAX_LUN;
2386 	esp->host->cmd_per_lun = 2;
2387 	esp->host->unique_id = instance;
2388 
2389 	esp_set_clock_params(esp);
2390 
2391 	esp_get_revision(esp);
2392 
2393 	esp_init_swstate(esp);
2394 
2395 	esp_bootup_reset(esp);
2396 
2397 	dev_printk(KERN_INFO, esp->dev, "esp%u: regs[%1p:%1p] irq[%u]\n",
2398 		   esp->host->unique_id, esp->regs, esp->dma_regs,
2399 		   esp->host->irq);
2400 	dev_printk(KERN_INFO, esp->dev,
2401 		   "esp%u: is a %s, %u MHz (ccf=%u), SCSI ID %u\n",
2402 		   esp->host->unique_id, esp_chip_names[esp->rev],
2403 		   esp->cfreq / 1000000, esp->cfact, esp->scsi_id);
2404 
2405 	/* Let the SCSI bus reset settle. */
2406 	ssleep(esp_bus_reset_settle);
2407 
2408 	err = scsi_add_host(esp->host, esp->dev);
2409 	if (err)
2410 		return err;
2411 
2412 	instance++;
2413 
2414 	scsi_scan_host(esp->host);
2415 
2416 	return 0;
2417 }
2418 EXPORT_SYMBOL(scsi_esp_register);
2419 
scsi_esp_unregister(struct esp * esp)2420 void scsi_esp_unregister(struct esp *esp)
2421 {
2422 	scsi_remove_host(esp->host);
2423 }
2424 EXPORT_SYMBOL(scsi_esp_unregister);
2425 
esp_target_alloc(struct scsi_target * starget)2426 static int esp_target_alloc(struct scsi_target *starget)
2427 {
2428 	struct esp *esp = shost_priv(dev_to_shost(&starget->dev));
2429 	struct esp_target_data *tp = &esp->target[starget->id];
2430 
2431 	tp->starget = starget;
2432 
2433 	return 0;
2434 }
2435 
esp_target_destroy(struct scsi_target * starget)2436 static void esp_target_destroy(struct scsi_target *starget)
2437 {
2438 	struct esp *esp = shost_priv(dev_to_shost(&starget->dev));
2439 	struct esp_target_data *tp = &esp->target[starget->id];
2440 
2441 	tp->starget = NULL;
2442 }
2443 
esp_slave_alloc(struct scsi_device * dev)2444 static int esp_slave_alloc(struct scsi_device *dev)
2445 {
2446 	struct esp *esp = shost_priv(dev->host);
2447 	struct esp_target_data *tp = &esp->target[dev->id];
2448 	struct esp_lun_data *lp;
2449 
2450 	lp = kzalloc(sizeof(*lp), GFP_KERNEL);
2451 	if (!lp)
2452 		return -ENOMEM;
2453 	dev->hostdata = lp;
2454 
2455 	spi_min_period(tp->starget) = esp->min_period;
2456 	spi_max_offset(tp->starget) = 15;
2457 
2458 	if (esp->flags & ESP_FLAG_WIDE_CAPABLE)
2459 		spi_max_width(tp->starget) = 1;
2460 	else
2461 		spi_max_width(tp->starget) = 0;
2462 
2463 	return 0;
2464 }
2465 
esp_slave_configure(struct scsi_device * dev)2466 static int esp_slave_configure(struct scsi_device *dev)
2467 {
2468 	struct esp *esp = shost_priv(dev->host);
2469 	struct esp_target_data *tp = &esp->target[dev->id];
2470 
2471 	if (dev->tagged_supported)
2472 		scsi_change_queue_depth(dev, esp->num_tags);
2473 
2474 	tp->flags |= ESP_TGT_DISCONNECT;
2475 
2476 	if (!spi_initial_dv(dev->sdev_target))
2477 		spi_dv_device(dev);
2478 
2479 	return 0;
2480 }
2481 
esp_slave_destroy(struct scsi_device * dev)2482 static void esp_slave_destroy(struct scsi_device *dev)
2483 {
2484 	struct esp_lun_data *lp = dev->hostdata;
2485 
2486 	kfree(lp);
2487 	dev->hostdata = NULL;
2488 }
2489 
esp_eh_abort_handler(struct scsi_cmnd * cmd)2490 static int esp_eh_abort_handler(struct scsi_cmnd *cmd)
2491 {
2492 	struct esp *esp = shost_priv(cmd->device->host);
2493 	struct esp_cmd_entry *ent, *tmp;
2494 	struct completion eh_done;
2495 	unsigned long flags;
2496 
2497 	/* XXX This helps a lot with debugging but might be a bit
2498 	 * XXX much for the final driver.
2499 	 */
2500 	spin_lock_irqsave(esp->host->host_lock, flags);
2501 	shost_printk(KERN_ERR, esp->host, "Aborting command [%p:%02x]\n",
2502 		     cmd, cmd->cmnd[0]);
2503 	ent = esp->active_cmd;
2504 	if (ent)
2505 		shost_printk(KERN_ERR, esp->host,
2506 			     "Current command [%p:%02x]\n",
2507 			     ent->cmd, ent->cmd->cmnd[0]);
2508 	list_for_each_entry(ent, &esp->queued_cmds, list) {
2509 		shost_printk(KERN_ERR, esp->host, "Queued command [%p:%02x]\n",
2510 			     ent->cmd, ent->cmd->cmnd[0]);
2511 	}
2512 	list_for_each_entry(ent, &esp->active_cmds, list) {
2513 		shost_printk(KERN_ERR, esp->host, " Active command [%p:%02x]\n",
2514 			     ent->cmd, ent->cmd->cmnd[0]);
2515 	}
2516 	esp_dump_cmd_log(esp);
2517 	spin_unlock_irqrestore(esp->host->host_lock, flags);
2518 
2519 	spin_lock_irqsave(esp->host->host_lock, flags);
2520 
2521 	ent = NULL;
2522 	list_for_each_entry(tmp, &esp->queued_cmds, list) {
2523 		if (tmp->cmd == cmd) {
2524 			ent = tmp;
2525 			break;
2526 		}
2527 	}
2528 
2529 	if (ent) {
2530 		/* Easiest case, we didn't even issue the command
2531 		 * yet so it is trivial to abort.
2532 		 */
2533 		list_del(&ent->list);
2534 
2535 		cmd->result = DID_ABORT << 16;
2536 		scsi_done(cmd);
2537 
2538 		esp_put_ent(esp, ent);
2539 
2540 		goto out_success;
2541 	}
2542 
2543 	init_completion(&eh_done);
2544 
2545 	ent = esp->active_cmd;
2546 	if (ent && ent->cmd == cmd) {
2547 		/* Command is the currently active command on
2548 		 * the bus.  If we already have an output message
2549 		 * pending, no dice.
2550 		 */
2551 		if (esp->msg_out_len)
2552 			goto out_failure;
2553 
2554 		/* Send out an abort, encouraging the target to
2555 		 * go to MSGOUT phase by asserting ATN.
2556 		 */
2557 		esp->msg_out[0] = ABORT_TASK_SET;
2558 		esp->msg_out_len = 1;
2559 		ent->eh_done = &eh_done;
2560 
2561 		scsi_esp_cmd(esp, ESP_CMD_SATN);
2562 	} else {
2563 		/* The command is disconnected.  This is not easy to
2564 		 * abort.  For now we fail and let the scsi error
2565 		 * handling layer go try a scsi bus reset or host
2566 		 * reset.
2567 		 *
2568 		 * What we could do is put together a scsi command
2569 		 * solely for the purpose of sending an abort message
2570 		 * to the target.  Coming up with all the code to
2571 		 * cook up scsi commands, special case them everywhere,
2572 		 * etc. is for questionable gain and it would be better
2573 		 * if the generic scsi error handling layer could do at
2574 		 * least some of that for us.
2575 		 *
2576 		 * Anyways this is an area for potential future improvement
2577 		 * in this driver.
2578 		 */
2579 		goto out_failure;
2580 	}
2581 
2582 	spin_unlock_irqrestore(esp->host->host_lock, flags);
2583 
2584 	if (!wait_for_completion_timeout(&eh_done, 5 * HZ)) {
2585 		spin_lock_irqsave(esp->host->host_lock, flags);
2586 		ent->eh_done = NULL;
2587 		spin_unlock_irqrestore(esp->host->host_lock, flags);
2588 
2589 		return FAILED;
2590 	}
2591 
2592 	return SUCCESS;
2593 
2594 out_success:
2595 	spin_unlock_irqrestore(esp->host->host_lock, flags);
2596 	return SUCCESS;
2597 
2598 out_failure:
2599 	/* XXX This might be a good location to set ESP_TGT_BROKEN
2600 	 * XXX since we know which target/lun in particular is
2601 	 * XXX causing trouble.
2602 	 */
2603 	spin_unlock_irqrestore(esp->host->host_lock, flags);
2604 	return FAILED;
2605 }
2606 
esp_eh_bus_reset_handler(struct scsi_cmnd * cmd)2607 static int esp_eh_bus_reset_handler(struct scsi_cmnd *cmd)
2608 {
2609 	struct esp *esp = shost_priv(cmd->device->host);
2610 	struct completion eh_reset;
2611 	unsigned long flags;
2612 
2613 	init_completion(&eh_reset);
2614 
2615 	spin_lock_irqsave(esp->host->host_lock, flags);
2616 
2617 	esp->eh_reset = &eh_reset;
2618 
2619 	/* XXX This is too simple... We should add lots of
2620 	 * XXX checks here so that if we find that the chip is
2621 	 * XXX very wedged we return failure immediately so
2622 	 * XXX that we can perform a full chip reset.
2623 	 */
2624 	esp->flags |= ESP_FLAG_RESETTING;
2625 	scsi_esp_cmd(esp, ESP_CMD_RS);
2626 
2627 	spin_unlock_irqrestore(esp->host->host_lock, flags);
2628 
2629 	ssleep(esp_bus_reset_settle);
2630 
2631 	if (!wait_for_completion_timeout(&eh_reset, 5 * HZ)) {
2632 		spin_lock_irqsave(esp->host->host_lock, flags);
2633 		esp->eh_reset = NULL;
2634 		spin_unlock_irqrestore(esp->host->host_lock, flags);
2635 
2636 		return FAILED;
2637 	}
2638 
2639 	return SUCCESS;
2640 }
2641 
2642 /* All bets are off, reset the entire device.  */
esp_eh_host_reset_handler(struct scsi_cmnd * cmd)2643 static int esp_eh_host_reset_handler(struct scsi_cmnd *cmd)
2644 {
2645 	struct esp *esp = shost_priv(cmd->device->host);
2646 	unsigned long flags;
2647 
2648 	spin_lock_irqsave(esp->host->host_lock, flags);
2649 	esp_bootup_reset(esp);
2650 	esp_reset_cleanup(esp);
2651 	spin_unlock_irqrestore(esp->host->host_lock, flags);
2652 
2653 	ssleep(esp_bus_reset_settle);
2654 
2655 	return SUCCESS;
2656 }
2657 
esp_info(struct Scsi_Host * host)2658 static const char *esp_info(struct Scsi_Host *host)
2659 {
2660 	return "esp";
2661 }
2662 
2663 const struct scsi_host_template scsi_esp_template = {
2664 	.module			= THIS_MODULE,
2665 	.name			= "esp",
2666 	.info			= esp_info,
2667 	.queuecommand		= esp_queuecommand,
2668 	.target_alloc		= esp_target_alloc,
2669 	.target_destroy		= esp_target_destroy,
2670 	.slave_alloc		= esp_slave_alloc,
2671 	.slave_configure	= esp_slave_configure,
2672 	.slave_destroy		= esp_slave_destroy,
2673 	.eh_abort_handler	= esp_eh_abort_handler,
2674 	.eh_bus_reset_handler	= esp_eh_bus_reset_handler,
2675 	.eh_host_reset_handler	= esp_eh_host_reset_handler,
2676 	.can_queue		= 7,
2677 	.this_id		= 7,
2678 	.sg_tablesize		= SG_ALL,
2679 	.max_sectors		= 0xffff,
2680 	.skip_settle_delay	= 1,
2681 	.cmd_size		= sizeof(struct esp_cmd_priv),
2682 };
2683 EXPORT_SYMBOL(scsi_esp_template);
2684 
esp_get_signalling(struct Scsi_Host * host)2685 static void esp_get_signalling(struct Scsi_Host *host)
2686 {
2687 	struct esp *esp = shost_priv(host);
2688 	enum spi_signal_type type;
2689 
2690 	if (esp->flags & ESP_FLAG_DIFFERENTIAL)
2691 		type = SPI_SIGNAL_HVD;
2692 	else
2693 		type = SPI_SIGNAL_SE;
2694 
2695 	spi_signalling(host) = type;
2696 }
2697 
esp_set_offset(struct scsi_target * target,int offset)2698 static void esp_set_offset(struct scsi_target *target, int offset)
2699 {
2700 	struct Scsi_Host *host = dev_to_shost(target->dev.parent);
2701 	struct esp *esp = shost_priv(host);
2702 	struct esp_target_data *tp = &esp->target[target->id];
2703 
2704 	if (esp->flags & ESP_FLAG_DISABLE_SYNC)
2705 		tp->nego_goal_offset = 0;
2706 	else
2707 		tp->nego_goal_offset = offset;
2708 	tp->flags |= ESP_TGT_CHECK_NEGO;
2709 }
2710 
esp_set_period(struct scsi_target * target,int period)2711 static void esp_set_period(struct scsi_target *target, int period)
2712 {
2713 	struct Scsi_Host *host = dev_to_shost(target->dev.parent);
2714 	struct esp *esp = shost_priv(host);
2715 	struct esp_target_data *tp = &esp->target[target->id];
2716 
2717 	tp->nego_goal_period = period;
2718 	tp->flags |= ESP_TGT_CHECK_NEGO;
2719 }
2720 
esp_set_width(struct scsi_target * target,int width)2721 static void esp_set_width(struct scsi_target *target, int width)
2722 {
2723 	struct Scsi_Host *host = dev_to_shost(target->dev.parent);
2724 	struct esp *esp = shost_priv(host);
2725 	struct esp_target_data *tp = &esp->target[target->id];
2726 
2727 	tp->nego_goal_width = (width ? 1 : 0);
2728 	tp->flags |= ESP_TGT_CHECK_NEGO;
2729 }
2730 
2731 static struct spi_function_template esp_transport_ops = {
2732 	.set_offset		= esp_set_offset,
2733 	.show_offset		= 1,
2734 	.set_period		= esp_set_period,
2735 	.show_period		= 1,
2736 	.set_width		= esp_set_width,
2737 	.show_width		= 1,
2738 	.get_signalling		= esp_get_signalling,
2739 };
2740 
esp_init(void)2741 static int __init esp_init(void)
2742 {
2743 	esp_transport_template = spi_attach_transport(&esp_transport_ops);
2744 	if (!esp_transport_template)
2745 		return -ENODEV;
2746 
2747 	return 0;
2748 }
2749 
esp_exit(void)2750 static void __exit esp_exit(void)
2751 {
2752 	spi_release_transport(esp_transport_template);
2753 }
2754 
2755 MODULE_DESCRIPTION("ESP SCSI driver core");
2756 MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
2757 MODULE_LICENSE("GPL");
2758 MODULE_VERSION(DRV_VERSION);
2759 
2760 module_param(esp_bus_reset_settle, int, 0);
2761 MODULE_PARM_DESC(esp_bus_reset_settle,
2762 		 "ESP scsi bus reset delay in seconds");
2763 
2764 module_param(esp_debug, int, 0);
2765 MODULE_PARM_DESC(esp_debug,
2766 "ESP bitmapped debugging message enable value:\n"
2767 "	0x00000001	Log interrupt events\n"
2768 "	0x00000002	Log scsi commands\n"
2769 "	0x00000004	Log resets\n"
2770 "	0x00000008	Log message in events\n"
2771 "	0x00000010	Log message out events\n"
2772 "	0x00000020	Log command completion\n"
2773 "	0x00000040	Log disconnects\n"
2774 "	0x00000080	Log data start\n"
2775 "	0x00000100	Log data done\n"
2776 "	0x00000200	Log reconnects\n"
2777 "	0x00000400	Log auto-sense data\n"
2778 );
2779 
2780 module_init(esp_init);
2781 module_exit(esp_exit);
2782 
2783 #ifdef CONFIG_SCSI_ESP_PIO
esp_wait_for_fifo(struct esp * esp)2784 static inline unsigned int esp_wait_for_fifo(struct esp *esp)
2785 {
2786 	int i = 500000;
2787 
2788 	do {
2789 		unsigned int fbytes = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;
2790 
2791 		if (fbytes)
2792 			return fbytes;
2793 
2794 		udelay(1);
2795 	} while (--i);
2796 
2797 	shost_printk(KERN_ERR, esp->host, "FIFO is empty. sreg [%02x]\n",
2798 		     esp_read8(ESP_STATUS));
2799 	return 0;
2800 }
2801 
esp_wait_for_intr(struct esp * esp)2802 static inline int esp_wait_for_intr(struct esp *esp)
2803 {
2804 	int i = 500000;
2805 
2806 	do {
2807 		esp->sreg = esp_read8(ESP_STATUS);
2808 		if (esp->sreg & ESP_STAT_INTR)
2809 			return 0;
2810 
2811 		udelay(1);
2812 	} while (--i);
2813 
2814 	shost_printk(KERN_ERR, esp->host, "IRQ timeout. sreg [%02x]\n",
2815 		     esp->sreg);
2816 	return 1;
2817 }
2818 
2819 #define ESP_FIFO_SIZE 16
2820 
esp_send_pio_cmd(struct esp * esp,u32 addr,u32 esp_count,u32 dma_count,int write,u8 cmd)2821 void esp_send_pio_cmd(struct esp *esp, u32 addr, u32 esp_count,
2822 		      u32 dma_count, int write, u8 cmd)
2823 {
2824 	u8 phase = esp->sreg & ESP_STAT_PMASK;
2825 
2826 	cmd &= ~ESP_CMD_DMA;
2827 	esp->send_cmd_error = 0;
2828 
2829 	if (write) {
2830 		u8 *dst = (u8 *)addr;
2831 		u8 mask = ~(phase == ESP_MIP ? ESP_INTR_FDONE : ESP_INTR_BSERV);
2832 
2833 		scsi_esp_cmd(esp, cmd);
2834 
2835 		while (1) {
2836 			if (!esp_wait_for_fifo(esp))
2837 				break;
2838 
2839 			*dst++ = readb(esp->fifo_reg);
2840 			--esp_count;
2841 
2842 			if (!esp_count)
2843 				break;
2844 
2845 			if (esp_wait_for_intr(esp)) {
2846 				esp->send_cmd_error = 1;
2847 				break;
2848 			}
2849 
2850 			if ((esp->sreg & ESP_STAT_PMASK) != phase)
2851 				break;
2852 
2853 			esp->ireg = esp_read8(ESP_INTRPT);
2854 			if (esp->ireg & mask) {
2855 				esp->send_cmd_error = 1;
2856 				break;
2857 			}
2858 
2859 			if (phase == ESP_MIP)
2860 				esp_write8(ESP_CMD_MOK, ESP_CMD);
2861 
2862 			esp_write8(ESP_CMD_TI, ESP_CMD);
2863 		}
2864 	} else {
2865 		unsigned int n = ESP_FIFO_SIZE;
2866 		u8 *src = (u8 *)addr;
2867 
2868 		scsi_esp_cmd(esp, ESP_CMD_FLUSH);
2869 
2870 		if (n > esp_count)
2871 			n = esp_count;
2872 		writesb(esp->fifo_reg, src, n);
2873 		src += n;
2874 		esp_count -= n;
2875 
2876 		scsi_esp_cmd(esp, cmd);
2877 
2878 		while (esp_count) {
2879 			if (esp_wait_for_intr(esp)) {
2880 				esp->send_cmd_error = 1;
2881 				break;
2882 			}
2883 
2884 			if ((esp->sreg & ESP_STAT_PMASK) != phase)
2885 				break;
2886 
2887 			esp->ireg = esp_read8(ESP_INTRPT);
2888 			if (esp->ireg & ~ESP_INTR_BSERV) {
2889 				esp->send_cmd_error = 1;
2890 				break;
2891 			}
2892 
2893 			n = ESP_FIFO_SIZE -
2894 			    (esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES);
2895 
2896 			if (n > esp_count)
2897 				n = esp_count;
2898 			writesb(esp->fifo_reg, src, n);
2899 			src += n;
2900 			esp_count -= n;
2901 
2902 			esp_write8(ESP_CMD_TI, ESP_CMD);
2903 		}
2904 	}
2905 
2906 	esp->send_cmd_residual = esp_count;
2907 }
2908 EXPORT_SYMBOL(esp_send_pio_cmd);
2909 #endif
2910