1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AMD am53c974 driver.
4 * Copyright (c) 2014 Hannes Reinecke, SUSE Linux GmbH
5 */
6
7#include <linux/kernel.h>
8#include <linux/module.h>
9#include <linux/init.h>
10#include <linux/delay.h>
11#include <linux/pci.h>
12#include <linux/interrupt.h>
13
14#include <scsi/scsi_host.h>
15
16#include "esp_scsi.h"
17
18#define DRV_MODULE_NAME "am53c974"
19#define DRV_MODULE_VERSION "1.00"
20
21static bool am53c974_debug;
22static bool am53c974_fenab = true;
23
24#define esp_dma_log(f, a...) \
25 do { \
26 if (am53c974_debug) \
27 shost_printk(KERN_DEBUG, esp->host, f, ##a); \
28 } while (0)
29
30#define ESP_DMA_CMD 0x10
31#define ESP_DMA_STC 0x11
32#define ESP_DMA_SPA 0x12
33#define ESP_DMA_WBC 0x13
34#define ESP_DMA_WAC 0x14
35#define ESP_DMA_STATUS 0x15
36#define ESP_DMA_SMDLA 0x16
37#define ESP_DMA_WMAC 0x17
38
39#define ESP_DMA_CMD_IDLE 0x00
40#define ESP_DMA_CMD_BLAST 0x01
41#define ESP_DMA_CMD_ABORT 0x02
42#define ESP_DMA_CMD_START 0x03
43#define ESP_DMA_CMD_MASK 0x03
44#define ESP_DMA_CMD_DIAG 0x04
45#define ESP_DMA_CMD_MDL 0x10
46#define ESP_DMA_CMD_INTE_P 0x20
47#define ESP_DMA_CMD_INTE_D 0x40
48#define ESP_DMA_CMD_DIR 0x80
49
50#define ESP_DMA_STAT_PWDN 0x01
51#define ESP_DMA_STAT_ERROR 0x02
52#define ESP_DMA_STAT_ABORT 0x04
53#define ESP_DMA_STAT_DONE 0x08
54#define ESP_DMA_STAT_SCSIINT 0x10
55#define ESP_DMA_STAT_BCMPLT 0x20
56
57/* EEPROM is accessed with 16-bit values */
58#define DC390_EEPROM_READ 0x80
59#define DC390_EEPROM_LEN 0x40
60
61/*
62 * DC390 EEPROM
63 *
64 * 8 * 4 bytes of per-device options
65 * followed by HBA specific options
66 */
67
68/* Per-device options */
69#define DC390_EE_MODE1 0x00
70#define DC390_EE_SPEED 0x01
71
72/* HBA-specific options */
73#define DC390_EE_ADAPT_SCSI_ID 0x40
74#define DC390_EE_MODE2 0x41
75#define DC390_EE_DELAY 0x42
76#define DC390_EE_TAG_CMD_NUM 0x43
77
78#define DC390_EE_MODE1_PARITY_CHK 0x01
79#define DC390_EE_MODE1_SYNC_NEGO 0x02
80#define DC390_EE_MODE1_EN_DISC 0x04
81#define DC390_EE_MODE1_SEND_START 0x08
82#define DC390_EE_MODE1_TCQ 0x10
83
84#define DC390_EE_MODE2_MORE_2DRV 0x01
85#define DC390_EE_MODE2_GREATER_1G 0x02
86#define DC390_EE_MODE2_RST_SCSI_BUS 0x04
87#define DC390_EE_MODE2_ACTIVE_NEGATION 0x08
88#define DC390_EE_MODE2_NO_SEEK 0x10
89#define DC390_EE_MODE2_LUN_CHECK 0x20
90
91struct pci_esp_priv {
92 struct esp *esp;
93 u8 dma_status;
94};
95
96static void pci_esp_dma_drain(struct esp *esp);
97
98static inline struct pci_esp_priv *pci_esp_get_priv(struct esp *esp)
99{
100 return dev_get_drvdata(dev: esp->dev);
101}
102
103static void pci_esp_write8(struct esp *esp, u8 val, unsigned long reg)
104{
105 iowrite8(val, esp->regs + (reg * 4UL));
106}
107
108static u8 pci_esp_read8(struct esp *esp, unsigned long reg)
109{
110 return ioread8(esp->regs + (reg * 4UL));
111}
112
113static void pci_esp_write32(struct esp *esp, u32 val, unsigned long reg)
114{
115 return iowrite32(val, esp->regs + (reg * 4UL));
116}
117
118static int pci_esp_irq_pending(struct esp *esp)
119{
120 struct pci_esp_priv *pep = pci_esp_get_priv(esp);
121
122 pep->dma_status = pci_esp_read8(esp, ESP_DMA_STATUS);
123 esp_dma_log("dma intr dreg[%02x]\n", pep->dma_status);
124
125 if (pep->dma_status & (ESP_DMA_STAT_ERROR |
126 ESP_DMA_STAT_ABORT |
127 ESP_DMA_STAT_DONE |
128 ESP_DMA_STAT_SCSIINT))
129 return 1;
130
131 return 0;
132}
133
134static void pci_esp_reset_dma(struct esp *esp)
135{
136 /* Nothing to do ? */
137}
138
139static void pci_esp_dma_drain(struct esp *esp)
140{
141 u8 resid;
142 int lim = 1000;
143
144
145 if ((esp->sreg & ESP_STAT_PMASK) == ESP_DOP ||
146 (esp->sreg & ESP_STAT_PMASK) == ESP_DIP)
147 /* Data-In or Data-Out, nothing to be done */
148 return;
149
150 while (--lim > 0) {
151 resid = pci_esp_read8(esp, ESP_FFLAGS) & ESP_FF_FBYTES;
152 if (resid <= 1)
153 break;
154 cpu_relax();
155 }
156
157 /*
158 * When there is a residual BCMPLT will never be set
159 * (obviously). But we still have to issue the BLAST
160 * command, otherwise the data will not being transferred.
161 * But we'll never know when the BLAST operation is
162 * finished. So check for some time and give up eventually.
163 */
164 lim = 1000;
165 pci_esp_write8(esp, ESP_DMA_CMD_DIR | ESP_DMA_CMD_BLAST, ESP_DMA_CMD);
166 while (pci_esp_read8(esp, ESP_DMA_STATUS) & ESP_DMA_STAT_BCMPLT) {
167 if (--lim == 0)
168 break;
169 cpu_relax();
170 }
171 pci_esp_write8(esp, ESP_DMA_CMD_DIR | ESP_DMA_CMD_IDLE, ESP_DMA_CMD);
172 esp_dma_log("DMA blast done (%d tries, %d bytes left)\n", lim, resid);
173 /* BLAST residual handling is currently untested */
174 if (WARN_ON_ONCE(resid == 1)) {
175 struct esp_cmd_entry *ent = esp->active_cmd;
176
177 ent->flags |= ESP_CMD_FLAG_RESIDUAL;
178 }
179}
180
181static void pci_esp_dma_invalidate(struct esp *esp)
182{
183 struct pci_esp_priv *pep = pci_esp_get_priv(esp);
184
185 esp_dma_log("invalidate DMA\n");
186
187 pci_esp_write8(esp, ESP_DMA_CMD_IDLE, ESP_DMA_CMD);
188 pep->dma_status = 0;
189}
190
191static int pci_esp_dma_error(struct esp *esp)
192{
193 struct pci_esp_priv *pep = pci_esp_get_priv(esp);
194
195 if (pep->dma_status & ESP_DMA_STAT_ERROR) {
196 u8 dma_cmd = pci_esp_read8(esp, ESP_DMA_CMD);
197
198 if ((dma_cmd & ESP_DMA_CMD_MASK) == ESP_DMA_CMD_START)
199 pci_esp_write8(esp, ESP_DMA_CMD_ABORT, ESP_DMA_CMD);
200
201 return 1;
202 }
203 if (pep->dma_status & ESP_DMA_STAT_ABORT) {
204 pci_esp_write8(esp, ESP_DMA_CMD_IDLE, ESP_DMA_CMD);
205 pep->dma_status = pci_esp_read8(esp, ESP_DMA_CMD);
206 return 1;
207 }
208 return 0;
209}
210
211static void pci_esp_send_dma_cmd(struct esp *esp, u32 addr, u32 esp_count,
212 u32 dma_count, int write, u8 cmd)
213{
214 struct pci_esp_priv *pep = pci_esp_get_priv(esp);
215 u32 val = 0;
216
217 BUG_ON(!(cmd & ESP_CMD_DMA));
218
219 pep->dma_status = 0;
220
221 /* Set DMA engine to IDLE */
222 if (write)
223 /* DMA write direction logic is inverted */
224 val |= ESP_DMA_CMD_DIR;
225 pci_esp_write8(esp, ESP_DMA_CMD_IDLE | val, ESP_DMA_CMD);
226
227 pci_esp_write8(esp, val: (esp_count >> 0) & 0xff, ESP_TCLOW);
228 pci_esp_write8(esp, val: (esp_count >> 8) & 0xff, ESP_TCMED);
229 if (esp->config2 & ESP_CONFIG2_FENAB)
230 pci_esp_write8(esp, val: (esp_count >> 16) & 0xff, ESP_TCHI);
231
232 pci_esp_write32(esp, val: esp_count, ESP_DMA_STC);
233 pci_esp_write32(esp, val: addr, ESP_DMA_SPA);
234
235 esp_dma_log("start dma addr[%x] count[%d:%d]\n",
236 addr, esp_count, dma_count);
237
238 scsi_esp_cmd(esp, cmd);
239 /* Send DMA Start command */
240 pci_esp_write8(esp, ESP_DMA_CMD_START | val, ESP_DMA_CMD);
241}
242
243static u32 pci_esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len)
244{
245 int dma_limit = 16;
246 u32 base, end;
247
248 /*
249 * If CONFIG2_FENAB is set we can
250 * handle up to 24 bit addresses
251 */
252 if (esp->config2 & ESP_CONFIG2_FENAB)
253 dma_limit = 24;
254
255 if (dma_len > (1U << dma_limit))
256 dma_len = (1U << dma_limit);
257
258 /*
259 * Prevent crossing a 24-bit address boundary.
260 */
261 base = dma_addr & ((1U << 24) - 1U);
262 end = base + dma_len;
263 if (end > (1U << 24))
264 end = (1U <<24);
265 dma_len = end - base;
266
267 return dma_len;
268}
269
270static const struct esp_driver_ops pci_esp_ops = {
271 .esp_write8 = pci_esp_write8,
272 .esp_read8 = pci_esp_read8,
273 .irq_pending = pci_esp_irq_pending,
274 .reset_dma = pci_esp_reset_dma,
275 .dma_drain = pci_esp_dma_drain,
276 .dma_invalidate = pci_esp_dma_invalidate,
277 .send_dma_cmd = pci_esp_send_dma_cmd,
278 .dma_error = pci_esp_dma_error,
279 .dma_length_limit = pci_esp_dma_length_limit,
280};
281
282/*
283 * Read DC-390 eeprom
284 */
285static void dc390_eeprom_prepare_read(struct pci_dev *pdev, u8 cmd)
286{
287 u8 carry_flag = 1, j = 0x80, bval;
288 int i;
289
290 for (i = 0; i < 9; i++) {
291 if (carry_flag) {
292 pci_write_config_byte(dev: pdev, where: 0x80, val: 0x40);
293 bval = 0xc0;
294 } else
295 bval = 0x80;
296
297 udelay(160);
298 pci_write_config_byte(dev: pdev, where: 0x80, val: bval);
299 udelay(160);
300 pci_write_config_byte(dev: pdev, where: 0x80, val: 0);
301 udelay(160);
302
303 carry_flag = (cmd & j) ? 1 : 0;
304 j >>= 1;
305 }
306}
307
308static u16 dc390_eeprom_get_data(struct pci_dev *pdev)
309{
310 int i;
311 u16 wval = 0;
312 u8 bval;
313
314 for (i = 0; i < 16; i++) {
315 wval <<= 1;
316
317 pci_write_config_byte(dev: pdev, where: 0x80, val: 0x80);
318 udelay(160);
319 pci_write_config_byte(dev: pdev, where: 0x80, val: 0x40);
320 udelay(160);
321 pci_read_config_byte(dev: pdev, where: 0x00, val: &bval);
322
323 if (bval == 0x22)
324 wval |= 1;
325 }
326
327 return wval;
328}
329
330static void dc390_read_eeprom(struct pci_dev *pdev, u16 *ptr)
331{
332 u8 cmd = DC390_EEPROM_READ, i;
333
334 for (i = 0; i < DC390_EEPROM_LEN; i++) {
335 pci_write_config_byte(dev: pdev, where: 0xc0, val: 0);
336 udelay(160);
337
338 dc390_eeprom_prepare_read(pdev, cmd: cmd++);
339 *ptr++ = dc390_eeprom_get_data(pdev);
340
341 pci_write_config_byte(dev: pdev, where: 0x80, val: 0);
342 pci_write_config_byte(dev: pdev, where: 0x80, val: 0);
343 udelay(160);
344 }
345}
346
347static void dc390_check_eeprom(struct esp *esp)
348{
349 struct pci_dev *pdev = to_pci_dev(esp->dev);
350 u8 EEbuf[128];
351 u16 *ptr = (u16 *)EEbuf, wval = 0;
352 int i;
353
354 dc390_read_eeprom(pdev, ptr);
355
356 for (i = 0; i < DC390_EEPROM_LEN; i++, ptr++)
357 wval += *ptr;
358
359 /* no Tekram EEprom found */
360 if (wval != 0x1234) {
361 dev_printk(KERN_INFO, &pdev->dev,
362 "No valid Tekram EEprom found\n");
363 return;
364 }
365 esp->scsi_id = EEbuf[DC390_EE_ADAPT_SCSI_ID];
366 esp->num_tags = 2 << EEbuf[DC390_EE_TAG_CMD_NUM];
367 if (EEbuf[DC390_EE_MODE2] & DC390_EE_MODE2_ACTIVE_NEGATION)
368 esp->config4 |= ESP_CONFIG4_RADE | ESP_CONFIG4_RAE;
369}
370
371static int pci_esp_probe_one(struct pci_dev *pdev,
372 const struct pci_device_id *id)
373{
374 const struct scsi_host_template *hostt = &scsi_esp_template;
375 int err = -ENODEV;
376 struct Scsi_Host *shost;
377 struct esp *esp;
378 struct pci_esp_priv *pep;
379
380 if (pci_enable_device(dev: pdev)) {
381 dev_printk(KERN_INFO, &pdev->dev, "cannot enable device\n");
382 return -ENODEV;
383 }
384
385 if (dma_set_mask(dev: &pdev->dev, DMA_BIT_MASK(32))) {
386 dev_printk(KERN_INFO, &pdev->dev,
387 "failed to set 32bit DMA mask\n");
388 goto fail_disable_device;
389 }
390
391 shost = scsi_host_alloc(hostt, sizeof(struct esp));
392 if (!shost) {
393 dev_printk(KERN_INFO, &pdev->dev,
394 "failed to allocate scsi host\n");
395 err = -ENOMEM;
396 goto fail_disable_device;
397 }
398
399 pep = kzalloc(size: sizeof(struct pci_esp_priv), GFP_KERNEL);
400 if (!pep) {
401 dev_printk(KERN_INFO, &pdev->dev,
402 "failed to allocate esp_priv\n");
403 err = -ENOMEM;
404 goto fail_host_alloc;
405 }
406
407 esp = shost_priv(shost);
408 esp->host = shost;
409 esp->dev = &pdev->dev;
410 esp->ops = &pci_esp_ops;
411 /*
412 * The am53c974 HBA has a design flaw of generating
413 * spurious DMA completion interrupts when using
414 * DMA for command submission.
415 */
416 esp->flags |= ESP_FLAG_USE_FIFO;
417 /*
418 * Enable CONFIG2_FENAB to allow for large DMA transfers
419 */
420 if (am53c974_fenab)
421 esp->config2 |= ESP_CONFIG2_FENAB;
422
423 pep->esp = esp;
424
425 if (pci_request_regions(pdev, DRV_MODULE_NAME)) {
426 dev_printk(KERN_ERR, &pdev->dev,
427 "pci memory selection failed\n");
428 goto fail_priv_alloc;
429 }
430
431 esp->regs = pci_iomap(dev: pdev, bar: 0, pci_resource_len(pdev, 0));
432 if (!esp->regs) {
433 dev_printk(KERN_ERR, &pdev->dev, "pci I/O map failed\n");
434 err = -EINVAL;
435 goto fail_release_regions;
436 }
437 esp->dma_regs = esp->regs;
438
439 pci_set_master(dev: pdev);
440
441 esp->command_block = dma_alloc_coherent(dev: &pdev->dev, size: 16,
442 dma_handle: &esp->command_block_dma, GFP_KERNEL);
443 if (!esp->command_block) {
444 dev_printk(KERN_ERR, &pdev->dev,
445 "failed to allocate command block\n");
446 err = -ENOMEM;
447 goto fail_unmap_regs;
448 }
449
450 pci_set_drvdata(pdev, data: pep);
451
452 err = request_irq(irq: pdev->irq, handler: scsi_esp_intr, IRQF_SHARED,
453 DRV_MODULE_NAME, dev: esp);
454 if (err < 0) {
455 dev_printk(KERN_ERR, &pdev->dev, "failed to register IRQ\n");
456 goto fail_unmap_command_block;
457 }
458
459 esp->scsi_id = 7;
460 dc390_check_eeprom(esp);
461
462 shost->this_id = esp->scsi_id;
463 shost->max_id = 8;
464 shost->irq = pdev->irq;
465 shost->io_port = pci_resource_start(pdev, 0);
466 shost->n_io_port = pci_resource_len(pdev, 0);
467 shost->unique_id = shost->io_port;
468 esp->scsi_id_mask = (1 << esp->scsi_id);
469 /* Assume 40MHz clock */
470 esp->cfreq = 40000000;
471
472 err = scsi_esp_register(esp);
473 if (err)
474 goto fail_free_irq;
475
476 return 0;
477
478fail_free_irq:
479 free_irq(pdev->irq, esp);
480fail_unmap_command_block:
481 pci_set_drvdata(pdev, NULL);
482 dma_free_coherent(dev: &pdev->dev, size: 16, cpu_addr: esp->command_block,
483 dma_handle: esp->command_block_dma);
484fail_unmap_regs:
485 pci_iounmap(dev: pdev, esp->regs);
486fail_release_regions:
487 pci_release_regions(pdev);
488fail_priv_alloc:
489 kfree(objp: pep);
490fail_host_alloc:
491 scsi_host_put(t: shost);
492fail_disable_device:
493 pci_disable_device(dev: pdev);
494
495 return err;
496}
497
498static void pci_esp_remove_one(struct pci_dev *pdev)
499{
500 struct pci_esp_priv *pep = pci_get_drvdata(pdev);
501 struct esp *esp = pep->esp;
502
503 scsi_esp_unregister(esp);
504 free_irq(pdev->irq, esp);
505 pci_set_drvdata(pdev, NULL);
506 dma_free_coherent(dev: &pdev->dev, size: 16, cpu_addr: esp->command_block,
507 dma_handle: esp->command_block_dma);
508 pci_iounmap(dev: pdev, esp->regs);
509 pci_release_regions(pdev);
510 pci_disable_device(dev: pdev);
511 kfree(objp: pep);
512
513 scsi_host_put(t: esp->host);
514}
515
516static struct pci_device_id am53c974_pci_tbl[] = {
517 { PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_SCSI,
518 PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0 },
519 { }
520};
521MODULE_DEVICE_TABLE(pci, am53c974_pci_tbl);
522
523static struct pci_driver am53c974_driver = {
524 .name = DRV_MODULE_NAME,
525 .id_table = am53c974_pci_tbl,
526 .probe = pci_esp_probe_one,
527 .remove = pci_esp_remove_one,
528};
529
530module_pci_driver(am53c974_driver);
531
532MODULE_DESCRIPTION("AM53C974 SCSI driver");
533MODULE_AUTHOR("Hannes Reinecke <hare@suse.de>");
534MODULE_LICENSE("GPL");
535MODULE_VERSION(DRV_MODULE_VERSION);
536MODULE_ALIAS("tmscsim");
537
538module_param(am53c974_debug, bool, 0644);
539MODULE_PARM_DESC(am53c974_debug, "Enable debugging");
540
541module_param(am53c974_fenab, bool, 0444);
542MODULE_PARM_DESC(am53c974_fenab, "Enable 24-bit DMA transfer sizes");
543

source code of linux/drivers/scsi/am53c974.c