xref: /linux/drivers/scsi/am53c974.c (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
1 /*
2  * AMD am53c974 driver.
3  * Copyright (c) 2014 Hannes Reinecke, SUSE Linux GmbH
4  */
5 
6 #include <linux/kernel.h>
7 #include <linux/module.h>
8 #include <linux/init.h>
9 #include <linux/delay.h>
10 #include <linux/pci.h>
11 #include <linux/interrupt.h>
12 
13 #include <scsi/scsi_host.h>
14 
15 #include "esp_scsi.h"
16 
17 #define DRV_MODULE_NAME "am53c974"
18 #define DRV_MODULE_VERSION "1.00"
19 
20 static bool am53c974_debug;
21 static bool am53c974_fenab = true;
22 
23 #define esp_dma_log(f, a...)						\
24 	do {								\
25 		if (am53c974_debug)					\
26 			shost_printk(KERN_DEBUG, esp->host, f, ##a);	\
27 	} while (0)
28 
29 #define ESP_DMA_CMD 0x10
30 #define ESP_DMA_STC 0x11
31 #define ESP_DMA_SPA 0x12
32 #define ESP_DMA_WBC 0x13
33 #define ESP_DMA_WAC 0x14
34 #define ESP_DMA_STATUS 0x15
35 #define ESP_DMA_SMDLA 0x16
36 #define ESP_DMA_WMAC 0x17
37 
38 #define ESP_DMA_CMD_IDLE 0x00
39 #define ESP_DMA_CMD_BLAST 0x01
40 #define ESP_DMA_CMD_ABORT 0x02
41 #define ESP_DMA_CMD_START 0x03
42 #define ESP_DMA_CMD_MASK  0x03
43 #define ESP_DMA_CMD_DIAG 0x04
44 #define ESP_DMA_CMD_MDL 0x10
45 #define ESP_DMA_CMD_INTE_P 0x20
46 #define ESP_DMA_CMD_INTE_D 0x40
47 #define ESP_DMA_CMD_DIR 0x80
48 
49 #define ESP_DMA_STAT_PWDN 0x01
50 #define ESP_DMA_STAT_ERROR 0x02
51 #define ESP_DMA_STAT_ABORT 0x04
52 #define ESP_DMA_STAT_DONE 0x08
53 #define ESP_DMA_STAT_SCSIINT 0x10
54 #define ESP_DMA_STAT_BCMPLT 0x20
55 
56 /* EEPROM is accessed with 16-bit values */
57 #define DC390_EEPROM_READ 0x80
58 #define DC390_EEPROM_LEN 0x40
59 
60 /*
61  * DC390 EEPROM
62  *
63  * 8 * 4 bytes of per-device options
64  * followed by HBA specific options
65  */
66 
67 /* Per-device options */
68 #define DC390_EE_MODE1 0x00
69 #define DC390_EE_SPEED 0x01
70 
71 /* HBA-specific options */
72 #define DC390_EE_ADAPT_SCSI_ID 0x40
73 #define DC390_EE_MODE2 0x41
74 #define DC390_EE_DELAY 0x42
75 #define DC390_EE_TAG_CMD_NUM 0x43
76 
77 #define DC390_EE_MODE1_PARITY_CHK   0x01
78 #define DC390_EE_MODE1_SYNC_NEGO    0x02
79 #define DC390_EE_MODE1_EN_DISC      0x04
80 #define DC390_EE_MODE1_SEND_START   0x08
81 #define DC390_EE_MODE1_TCQ          0x10
82 
83 #define DC390_EE_MODE2_MORE_2DRV    0x01
84 #define DC390_EE_MODE2_GREATER_1G   0x02
85 #define DC390_EE_MODE2_RST_SCSI_BUS 0x04
86 #define DC390_EE_MODE2_ACTIVE_NEGATION 0x08
87 #define DC390_EE_MODE2_NO_SEEK      0x10
88 #define DC390_EE_MODE2_LUN_CHECK    0x20
89 
90 struct pci_esp_priv {
91 	struct esp *esp;
92 	u8 dma_status;
93 };
94 
95 static void pci_esp_dma_drain(struct esp *esp);
96 
97 static inline struct pci_esp_priv *pci_esp_get_priv(struct esp *esp)
98 {
99 	struct pci_dev *pdev = esp->dev;
100 
101 	return pci_get_drvdata(pdev);
102 }
103 
104 static void pci_esp_write8(struct esp *esp, u8 val, unsigned long reg)
105 {
106 	iowrite8(val, esp->regs + (reg * 4UL));
107 }
108 
109 static u8 pci_esp_read8(struct esp *esp, unsigned long reg)
110 {
111 	return ioread8(esp->regs + (reg * 4UL));
112 }
113 
114 static void pci_esp_write32(struct esp *esp, u32 val, unsigned long reg)
115 {
116 	return iowrite32(val, esp->regs + (reg * 4UL));
117 }
118 
119 static dma_addr_t pci_esp_map_single(struct esp *esp, void *buf,
120 				     size_t sz, int dir)
121 {
122 	return pci_map_single(esp->dev, buf, sz, dir);
123 }
124 
125 static int pci_esp_map_sg(struct esp *esp, struct scatterlist *sg,
126 			  int num_sg, int dir)
127 {
128 	return pci_map_sg(esp->dev, sg, num_sg, dir);
129 }
130 
131 static void pci_esp_unmap_single(struct esp *esp, dma_addr_t addr,
132 				 size_t sz, int dir)
133 {
134 	pci_unmap_single(esp->dev, addr, sz, dir);
135 }
136 
137 static void pci_esp_unmap_sg(struct esp *esp, struct scatterlist *sg,
138 			     int num_sg, int dir)
139 {
140 	pci_unmap_sg(esp->dev, sg, num_sg, dir);
141 }
142 
143 static int pci_esp_irq_pending(struct esp *esp)
144 {
145 	struct pci_esp_priv *pep = pci_esp_get_priv(esp);
146 
147 	pep->dma_status = pci_esp_read8(esp, ESP_DMA_STATUS);
148 	esp_dma_log("dma intr dreg[%02x]\n", pep->dma_status);
149 
150 	if (pep->dma_status & (ESP_DMA_STAT_ERROR |
151 			       ESP_DMA_STAT_ABORT |
152 			       ESP_DMA_STAT_DONE |
153 			       ESP_DMA_STAT_SCSIINT))
154 		return 1;
155 
156 	return 0;
157 }
158 
159 static void pci_esp_reset_dma(struct esp *esp)
160 {
161 	/* Nothing to do ? */
162 }
163 
164 static void pci_esp_dma_drain(struct esp *esp)
165 {
166 	u8 resid;
167 	int lim = 1000;
168 
169 
170 	if ((esp->sreg & ESP_STAT_PMASK) == ESP_DOP ||
171 	    (esp->sreg & ESP_STAT_PMASK) == ESP_DIP)
172 		/* Data-In or Data-Out, nothing to be done */
173 		return;
174 
175 	while (--lim > 0) {
176 		resid = pci_esp_read8(esp, ESP_FFLAGS) & ESP_FF_FBYTES;
177 		if (resid <= 1)
178 			break;
179 		cpu_relax();
180 	}
181 	if (resid > 1) {
182 		/* FIFO not cleared */
183 		shost_printk(KERN_INFO, esp->host,
184 			     "FIFO not cleared, %d bytes left\n",
185 			     resid);
186 	}
187 
188 	/*
189 	 * When there is a residual BCMPLT will never be set
190 	 * (obviously). But we still have to issue the BLAST
191 	 * command, otherwise the data will not being transferred.
192 	 * But we'll never know when the BLAST operation is
193 	 * finished. So check for some time and give up eventually.
194 	 */
195 	lim = 1000;
196 	pci_esp_write8(esp, ESP_DMA_CMD_DIR | ESP_DMA_CMD_BLAST, ESP_DMA_CMD);
197 	while (pci_esp_read8(esp, ESP_DMA_STATUS) & ESP_DMA_STAT_BCMPLT) {
198 		if (--lim == 0)
199 			break;
200 		cpu_relax();
201 	}
202 	pci_esp_write8(esp, ESP_DMA_CMD_DIR | ESP_DMA_CMD_IDLE, ESP_DMA_CMD);
203 	esp_dma_log("DMA blast done (%d tries, %d bytes left)\n", lim, resid);
204 	/* BLAST residual handling is currently untested */
205 	if (WARN_ON_ONCE(resid == 1)) {
206 		struct esp_cmd_entry *ent = esp->active_cmd;
207 
208 		ent->flags |= ESP_CMD_FLAG_RESIDUAL;
209 	}
210 }
211 
212 static void pci_esp_dma_invalidate(struct esp *esp)
213 {
214 	struct pci_esp_priv *pep = pci_esp_get_priv(esp);
215 
216 	esp_dma_log("invalidate DMA\n");
217 
218 	pci_esp_write8(esp, ESP_DMA_CMD_IDLE, ESP_DMA_CMD);
219 	pep->dma_status = 0;
220 }
221 
222 static int pci_esp_dma_error(struct esp *esp)
223 {
224 	struct pci_esp_priv *pep = pci_esp_get_priv(esp);
225 
226 	if (pep->dma_status & ESP_DMA_STAT_ERROR) {
227 		u8 dma_cmd = pci_esp_read8(esp, ESP_DMA_CMD);
228 
229 		if ((dma_cmd & ESP_DMA_CMD_MASK) == ESP_DMA_CMD_START)
230 			pci_esp_write8(esp, ESP_DMA_CMD_ABORT, ESP_DMA_CMD);
231 
232 		return 1;
233 	}
234 	if (pep->dma_status & ESP_DMA_STAT_ABORT) {
235 		pci_esp_write8(esp, ESP_DMA_CMD_IDLE, ESP_DMA_CMD);
236 		pep->dma_status = pci_esp_read8(esp, ESP_DMA_CMD);
237 		return 1;
238 	}
239 	return 0;
240 }
241 
242 static void pci_esp_send_dma_cmd(struct esp *esp, u32 addr, u32 esp_count,
243 				 u32 dma_count, int write, u8 cmd)
244 {
245 	struct pci_esp_priv *pep = pci_esp_get_priv(esp);
246 	u32 val = 0;
247 
248 	BUG_ON(!(cmd & ESP_CMD_DMA));
249 
250 	pep->dma_status = 0;
251 
252 	/* Set DMA engine to IDLE */
253 	if (write)
254 		/* DMA write direction logic is inverted */
255 		val |= ESP_DMA_CMD_DIR;
256 	pci_esp_write8(esp, ESP_DMA_CMD_IDLE | val, ESP_DMA_CMD);
257 
258 	pci_esp_write8(esp, (esp_count >> 0) & 0xff, ESP_TCLOW);
259 	pci_esp_write8(esp, (esp_count >> 8) & 0xff, ESP_TCMED);
260 	if (esp->config2 & ESP_CONFIG2_FENAB)
261 		pci_esp_write8(esp, (esp_count >> 16) & 0xff, ESP_TCHI);
262 
263 	pci_esp_write32(esp, esp_count, ESP_DMA_STC);
264 	pci_esp_write32(esp, addr, ESP_DMA_SPA);
265 
266 	esp_dma_log("start dma addr[%x] count[%d:%d]\n",
267 		    addr, esp_count, dma_count);
268 
269 	scsi_esp_cmd(esp, cmd);
270 	/* Send DMA Start command */
271 	pci_esp_write8(esp, ESP_DMA_CMD_START | val, ESP_DMA_CMD);
272 }
273 
274 static u32 pci_esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len)
275 {
276 	int dma_limit = 16;
277 	u32 base, end;
278 
279 	/*
280 	 * If CONFIG2_FENAB is set we can
281 	 * handle up to 24 bit addresses
282 	 */
283 	if (esp->config2 & ESP_CONFIG2_FENAB)
284 		dma_limit = 24;
285 
286 	if (dma_len > (1U << dma_limit))
287 		dma_len = (1U << dma_limit);
288 
289 	/*
290 	 * Prevent crossing a 24-bit address boundary.
291 	 */
292 	base = dma_addr & ((1U << 24) - 1U);
293 	end = base + dma_len;
294 	if (end > (1U << 24))
295 		end = (1U <<24);
296 	dma_len = end - base;
297 
298 	return dma_len;
299 }
300 
301 static const struct esp_driver_ops pci_esp_ops = {
302 	.esp_write8	=	pci_esp_write8,
303 	.esp_read8	=	pci_esp_read8,
304 	.map_single	=	pci_esp_map_single,
305 	.map_sg		=	pci_esp_map_sg,
306 	.unmap_single	=	pci_esp_unmap_single,
307 	.unmap_sg	=	pci_esp_unmap_sg,
308 	.irq_pending	=	pci_esp_irq_pending,
309 	.reset_dma	=	pci_esp_reset_dma,
310 	.dma_drain	=	pci_esp_dma_drain,
311 	.dma_invalidate	=	pci_esp_dma_invalidate,
312 	.send_dma_cmd	=	pci_esp_send_dma_cmd,
313 	.dma_error	=	pci_esp_dma_error,
314 	.dma_length_limit =	pci_esp_dma_length_limit,
315 };
316 
317 /*
318  * Read DC-390 eeprom
319  */
320 static void dc390_eeprom_prepare_read(struct pci_dev *pdev, u8 cmd)
321 {
322 	u8 carry_flag = 1, j = 0x80, bval;
323 	int i;
324 
325 	for (i = 0; i < 9; i++) {
326 		if (carry_flag) {
327 			pci_write_config_byte(pdev, 0x80, 0x40);
328 			bval = 0xc0;
329 		} else
330 			bval = 0x80;
331 
332 		udelay(160);
333 		pci_write_config_byte(pdev, 0x80, bval);
334 		udelay(160);
335 		pci_write_config_byte(pdev, 0x80, 0);
336 		udelay(160);
337 
338 		carry_flag = (cmd & j) ? 1 : 0;
339 		j >>= 1;
340 	}
341 }
342 
343 static u16 dc390_eeprom_get_data(struct pci_dev *pdev)
344 {
345 	int i;
346 	u16 wval = 0;
347 	u8 bval;
348 
349 	for (i = 0; i < 16; i++) {
350 		wval <<= 1;
351 
352 		pci_write_config_byte(pdev, 0x80, 0x80);
353 		udelay(160);
354 		pci_write_config_byte(pdev, 0x80, 0x40);
355 		udelay(160);
356 		pci_read_config_byte(pdev, 0x00, &bval);
357 
358 		if (bval == 0x22)
359 			wval |= 1;
360 	}
361 
362 	return wval;
363 }
364 
365 static void dc390_read_eeprom(struct pci_dev *pdev, u16 *ptr)
366 {
367 	u8 cmd = DC390_EEPROM_READ, i;
368 
369 	for (i = 0; i < DC390_EEPROM_LEN; i++) {
370 		pci_write_config_byte(pdev, 0xc0, 0);
371 		udelay(160);
372 
373 		dc390_eeprom_prepare_read(pdev, cmd++);
374 		*ptr++ = dc390_eeprom_get_data(pdev);
375 
376 		pci_write_config_byte(pdev, 0x80, 0);
377 		pci_write_config_byte(pdev, 0x80, 0);
378 		udelay(160);
379 	}
380 }
381 
382 static void dc390_check_eeprom(struct esp *esp)
383 {
384 	u8 EEbuf[128];
385 	u16 *ptr = (u16 *)EEbuf, wval = 0;
386 	int i;
387 
388 	dc390_read_eeprom((struct pci_dev *)esp->dev, ptr);
389 
390 	for (i = 0; i < DC390_EEPROM_LEN; i++, ptr++)
391 		wval += *ptr;
392 
393 	/* no Tekram EEprom found */
394 	if (wval != 0x1234) {
395 		struct pci_dev *pdev = esp->dev;
396 		dev_printk(KERN_INFO, &pdev->dev,
397 			   "No valid Tekram EEprom found\n");
398 		return;
399 	}
400 	esp->scsi_id = EEbuf[DC390_EE_ADAPT_SCSI_ID];
401 	esp->num_tags = 2 << EEbuf[DC390_EE_TAG_CMD_NUM];
402 	if (EEbuf[DC390_EE_MODE2] & DC390_EE_MODE2_ACTIVE_NEGATION)
403 		esp->config4 |= ESP_CONFIG4_RADE | ESP_CONFIG4_RAE;
404 }
405 
406 static int pci_esp_probe_one(struct pci_dev *pdev,
407 			      const struct pci_device_id *id)
408 {
409 	struct scsi_host_template *hostt = &scsi_esp_template;
410 	int err = -ENODEV;
411 	struct Scsi_Host *shost;
412 	struct esp *esp;
413 	struct pci_esp_priv *pep;
414 
415 	if (pci_enable_device(pdev)) {
416 		dev_printk(KERN_INFO, &pdev->dev, "cannot enable device\n");
417 		return -ENODEV;
418 	}
419 
420 	if (pci_set_dma_mask(pdev, DMA_BIT_MASK(32))) {
421 		dev_printk(KERN_INFO, &pdev->dev,
422 			   "failed to set 32bit DMA mask\n");
423 		goto fail_disable_device;
424 	}
425 
426 	shost = scsi_host_alloc(hostt, sizeof(struct esp));
427 	if (!shost) {
428 		dev_printk(KERN_INFO, &pdev->dev,
429 			   "failed to allocate scsi host\n");
430 		err = -ENOMEM;
431 		goto fail_disable_device;
432 	}
433 
434 	pep = kzalloc(sizeof(struct pci_esp_priv), GFP_KERNEL);
435 	if (!pep) {
436 		dev_printk(KERN_INFO, &pdev->dev,
437 			   "failed to allocate esp_priv\n");
438 		err = -ENOMEM;
439 		goto fail_host_alloc;
440 	}
441 
442 	esp = shost_priv(shost);
443 	esp->host = shost;
444 	esp->dev = pdev;
445 	esp->ops = &pci_esp_ops;
446 	/*
447 	 * The am53c974 HBA has a design flaw of generating
448 	 * spurious DMA completion interrupts when using
449 	 * DMA for command submission.
450 	 */
451 	esp->flags |= ESP_FLAG_USE_FIFO;
452 	/*
453 	 * Enable CONFIG2_FENAB to allow for large DMA transfers
454 	 */
455 	if (am53c974_fenab)
456 		esp->config2 |= ESP_CONFIG2_FENAB;
457 
458 	pep->esp = esp;
459 
460 	if (pci_request_regions(pdev, DRV_MODULE_NAME)) {
461 		dev_printk(KERN_ERR, &pdev->dev,
462 			   "pci memory selection failed\n");
463 		goto fail_priv_alloc;
464 	}
465 
466 	esp->regs = pci_iomap(pdev, 0, pci_resource_len(pdev, 0));
467 	if (!esp->regs) {
468 		dev_printk(KERN_ERR, &pdev->dev, "pci I/O map failed\n");
469 		err = -EINVAL;
470 		goto fail_release_regions;
471 	}
472 	esp->dma_regs = esp->regs;
473 
474 	pci_set_master(pdev);
475 
476 	esp->command_block = pci_alloc_consistent(pdev, 16,
477 						  &esp->command_block_dma);
478 	if (!esp->command_block) {
479 		dev_printk(KERN_ERR, &pdev->dev,
480 			   "failed to allocate command block\n");
481 		err = -ENOMEM;
482 		goto fail_unmap_regs;
483 	}
484 
485 	err = request_irq(pdev->irq, scsi_esp_intr, IRQF_SHARED,
486 			  DRV_MODULE_NAME, esp);
487 	if (err < 0) {
488 		dev_printk(KERN_ERR, &pdev->dev, "failed to register IRQ\n");
489 		goto fail_unmap_command_block;
490 	}
491 
492 	esp->scsi_id = 7;
493 	dc390_check_eeprom(esp);
494 
495 	shost->this_id = esp->scsi_id;
496 	shost->max_id = 8;
497 	shost->irq = pdev->irq;
498 	shost->io_port = pci_resource_start(pdev, 0);
499 	shost->n_io_port = pci_resource_len(pdev, 0);
500 	shost->unique_id = shost->io_port;
501 	esp->scsi_id_mask = (1 << esp->scsi_id);
502 	/* Assume 40MHz clock */
503 	esp->cfreq = 40000000;
504 
505 	pci_set_drvdata(pdev, pep);
506 
507 	err = scsi_esp_register(esp, &pdev->dev);
508 	if (err)
509 		goto fail_free_irq;
510 
511 	return 0;
512 
513 fail_free_irq:
514 	free_irq(pdev->irq, esp);
515 fail_unmap_command_block:
516 	pci_free_consistent(pdev, 16, esp->command_block,
517 			    esp->command_block_dma);
518 fail_unmap_regs:
519 	pci_iounmap(pdev, esp->regs);
520 fail_release_regions:
521 	pci_release_regions(pdev);
522 fail_priv_alloc:
523 	kfree(pep);
524 fail_host_alloc:
525 	scsi_host_put(shost);
526 fail_disable_device:
527 	pci_disable_device(pdev);
528 
529 	return err;
530 }
531 
532 static void pci_esp_remove_one(struct pci_dev *pdev)
533 {
534 	struct pci_esp_priv *pep = pci_get_drvdata(pdev);
535 	struct esp *esp = pep->esp;
536 
537 	scsi_esp_unregister(esp);
538 	free_irq(pdev->irq, esp);
539 	pci_free_consistent(pdev, 16, esp->command_block,
540 			    esp->command_block_dma);
541 	pci_iounmap(pdev, esp->regs);
542 	pci_release_regions(pdev);
543 	pci_disable_device(pdev);
544 	kfree(pep);
545 
546 	scsi_host_put(esp->host);
547 }
548 
549 static struct pci_device_id am53c974_pci_tbl[] = {
550 	{ PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_SCSI,
551 		PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0 },
552 	{ }
553 };
554 MODULE_DEVICE_TABLE(pci, am53c974_pci_tbl);
555 
556 static struct pci_driver am53c974_driver = {
557 	.name           = DRV_MODULE_NAME,
558 	.id_table       = am53c974_pci_tbl,
559 	.probe          = pci_esp_probe_one,
560 	.remove         = pci_esp_remove_one,
561 };
562 
563 static int __init am53c974_module_init(void)
564 {
565 	return pci_register_driver(&am53c974_driver);
566 }
567 
568 static void __exit am53c974_module_exit(void)
569 {
570 	pci_unregister_driver(&am53c974_driver);
571 }
572 
573 MODULE_DESCRIPTION("AM53C974 SCSI driver");
574 MODULE_AUTHOR("Hannes Reinecke <hare@suse.de>");
575 MODULE_LICENSE("GPL");
576 MODULE_VERSION(DRV_MODULE_VERSION);
577 MODULE_ALIAS("tmscsim");
578 
579 module_param(am53c974_debug, bool, 0644);
580 MODULE_PARM_DESC(am53c974_debug, "Enable debugging");
581 
582 module_param(am53c974_fenab, bool, 0444);
583 MODULE_PARM_DESC(am53c974_fenab, "Enable 24-bit DMA transfer sizes");
584 
585 module_init(am53c974_module_init);
586 module_exit(am53c974_module_exit);
587