1 // SPDX-License-Identifier: GPL-2.0-only
2 /* sun_esp.c: ESP front-end for Sparc SBUS systems.
3 *
4 * Copyright (C) 2007, 2008 David S. Miller (davem@davemloft.net)
5 */
6
7 #include <linux/kernel.h>
8 #include <linux/types.h>
9 #include <linux/delay.h>
10 #include <linux/module.h>
11 #include <linux/mm.h>
12 #include <linux/init.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/of.h>
15 #include <linux/of_platform.h>
16 #include <linux/platform_device.h>
17 #include <linux/gfp.h>
18
19 #include <asm/irq.h>
20 #include <asm/io.h>
21 #include <asm/dma.h>
22
23 #include <scsi/scsi_host.h>
24
25 #include "esp_scsi.h"
26
27 #define DRV_MODULE_NAME "sun_esp"
28 #define PFX DRV_MODULE_NAME ": "
29 #define DRV_VERSION "1.100"
30 #define DRV_MODULE_RELDATE "August 27, 2008"
31
32 #define dma_read32(REG) \
33 sbus_readl(esp->dma_regs + (REG))
34 #define dma_write32(VAL, REG) \
35 sbus_writel((VAL), esp->dma_regs + (REG))
36
37 /* DVMA chip revisions */
38 enum dvma_rev {
39 dvmarev0,
40 dvmaesc1,
41 dvmarev1,
42 dvmarev2,
43 dvmarev3,
44 dvmarevplus,
45 dvmahme
46 };
47
esp_sbus_setup_dma(struct esp * esp,struct platform_device * dma_of)48 static int esp_sbus_setup_dma(struct esp *esp, struct platform_device *dma_of)
49 {
50 esp->dma = dma_of;
51
52 esp->dma_regs = of_ioremap(&dma_of->resource[0], 0,
53 resource_size(&dma_of->resource[0]),
54 "espdma");
55 if (!esp->dma_regs)
56 return -ENOMEM;
57
58 switch (dma_read32(DMA_CSR) & DMA_DEVICE_ID) {
59 case DMA_VERS0:
60 esp->dmarev = dvmarev0;
61 break;
62 case DMA_ESCV1:
63 esp->dmarev = dvmaesc1;
64 break;
65 case DMA_VERS1:
66 esp->dmarev = dvmarev1;
67 break;
68 case DMA_VERS2:
69 esp->dmarev = dvmarev2;
70 break;
71 case DMA_VERHME:
72 esp->dmarev = dvmahme;
73 break;
74 case DMA_VERSPLUS:
75 esp->dmarev = dvmarevplus;
76 break;
77 }
78
79 return 0;
80
81 }
82
esp_sbus_map_regs(struct esp * esp,int hme)83 static int esp_sbus_map_regs(struct esp *esp, int hme)
84 {
85 struct platform_device *op = to_platform_device(esp->dev);
86 struct resource *res;
87
88 /* On HME, two reg sets exist, first is DVMA,
89 * second is ESP registers.
90 */
91 if (hme)
92 res = &op->resource[1];
93 else
94 res = &op->resource[0];
95
96 esp->regs = of_ioremap(res, 0, SBUS_ESP_REG_SIZE, "ESP");
97 if (!esp->regs)
98 return -ENOMEM;
99
100 return 0;
101 }
102
esp_sbus_map_command_block(struct esp * esp)103 static int esp_sbus_map_command_block(struct esp *esp)
104 {
105 esp->command_block = dma_alloc_coherent(esp->dev, 16,
106 &esp->command_block_dma,
107 GFP_KERNEL);
108 if (!esp->command_block)
109 return -ENOMEM;
110 return 0;
111 }
112
esp_sbus_register_irq(struct esp * esp)113 static int esp_sbus_register_irq(struct esp *esp)
114 {
115 struct Scsi_Host *host = esp->host;
116 struct platform_device *op = to_platform_device(esp->dev);
117
118 host->irq = op->archdata.irqs[0];
119 return request_irq(host->irq, scsi_esp_intr, IRQF_SHARED, "ESP", esp);
120 }
121
esp_get_scsi_id(struct esp * esp,struct platform_device * espdma)122 static void esp_get_scsi_id(struct esp *esp, struct platform_device *espdma)
123 {
124 struct platform_device *op = to_platform_device(esp->dev);
125 struct device_node *dp;
126
127 dp = op->dev.of_node;
128 esp->scsi_id = of_getintprop_default(dp, "initiator-id", 0xff);
129 if (esp->scsi_id != 0xff)
130 goto done;
131
132 esp->scsi_id = of_getintprop_default(dp, "scsi-initiator-id", 0xff);
133 if (esp->scsi_id != 0xff)
134 goto done;
135
136 esp->scsi_id = of_getintprop_default(espdma->dev.of_node,
137 "scsi-initiator-id", 7);
138
139 done:
140 esp->host->this_id = esp->scsi_id;
141 esp->scsi_id_mask = (1 << esp->scsi_id);
142 }
143
esp_get_differential(struct esp * esp)144 static void esp_get_differential(struct esp *esp)
145 {
146 struct platform_device *op = to_platform_device(esp->dev);
147 struct device_node *dp;
148
149 dp = op->dev.of_node;
150 if (of_property_read_bool(dp, "differential"))
151 esp->flags |= ESP_FLAG_DIFFERENTIAL;
152 else
153 esp->flags &= ~ESP_FLAG_DIFFERENTIAL;
154 }
155
esp_get_clock_params(struct esp * esp)156 static void esp_get_clock_params(struct esp *esp)
157 {
158 struct platform_device *op = to_platform_device(esp->dev);
159 struct device_node *bus_dp, *dp;
160 int fmhz;
161
162 dp = op->dev.of_node;
163 bus_dp = dp->parent;
164
165 fmhz = of_getintprop_default(dp, "clock-frequency", 0);
166 if (fmhz == 0)
167 fmhz = of_getintprop_default(bus_dp, "clock-frequency", 0);
168
169 esp->cfreq = fmhz;
170 }
171
esp_get_bursts(struct esp * esp,struct platform_device * dma_of)172 static void esp_get_bursts(struct esp *esp, struct platform_device *dma_of)
173 {
174 struct device_node *dma_dp = dma_of->dev.of_node;
175 struct platform_device *op = to_platform_device(esp->dev);
176 struct device_node *dp;
177 u8 bursts, val;
178
179 dp = op->dev.of_node;
180 bursts = of_getintprop_default(dp, "burst-sizes", 0xff);
181 val = of_getintprop_default(dma_dp, "burst-sizes", 0xff);
182 if (val != 0xff)
183 bursts &= val;
184
185 val = of_getintprop_default(dma_dp->parent, "burst-sizes", 0xff);
186 if (val != 0xff)
187 bursts &= val;
188
189 if (bursts == 0xff ||
190 (bursts & DMA_BURST16) == 0 ||
191 (bursts & DMA_BURST32) == 0)
192 bursts = (DMA_BURST32 - 1);
193
194 esp->bursts = bursts;
195 }
196
esp_sbus_get_props(struct esp * esp,struct platform_device * espdma)197 static void esp_sbus_get_props(struct esp *esp, struct platform_device *espdma)
198 {
199 esp_get_scsi_id(esp, espdma);
200 esp_get_differential(esp);
201 esp_get_clock_params(esp);
202 esp_get_bursts(esp, espdma);
203 }
204
sbus_esp_write8(struct esp * esp,u8 val,unsigned long reg)205 static void sbus_esp_write8(struct esp *esp, u8 val, unsigned long reg)
206 {
207 sbus_writeb(val, esp->regs + (reg * 4UL));
208 }
209
sbus_esp_read8(struct esp * esp,unsigned long reg)210 static u8 sbus_esp_read8(struct esp *esp, unsigned long reg)
211 {
212 return sbus_readb(esp->regs + (reg * 4UL));
213 }
214
sbus_esp_irq_pending(struct esp * esp)215 static int sbus_esp_irq_pending(struct esp *esp)
216 {
217 if (dma_read32(DMA_CSR) & (DMA_HNDL_INTR | DMA_HNDL_ERROR))
218 return 1;
219 return 0;
220 }
221
sbus_esp_reset_dma(struct esp * esp)222 static void sbus_esp_reset_dma(struct esp *esp)
223 {
224 int can_do_burst16, can_do_burst32, can_do_burst64;
225 int can_do_sbus64, lim;
226 struct platform_device *op = to_platform_device(esp->dev);
227 u32 val;
228
229 can_do_burst16 = (esp->bursts & DMA_BURST16) != 0;
230 can_do_burst32 = (esp->bursts & DMA_BURST32) != 0;
231 can_do_burst64 = 0;
232 can_do_sbus64 = 0;
233 if (sbus_can_dma_64bit())
234 can_do_sbus64 = 1;
235 if (sbus_can_burst64())
236 can_do_burst64 = (esp->bursts & DMA_BURST64) != 0;
237
238 /* Put the DVMA into a known state. */
239 if (esp->dmarev != dvmahme) {
240 val = dma_read32(DMA_CSR);
241 dma_write32(val | DMA_RST_SCSI, DMA_CSR);
242 dma_write32(val & ~DMA_RST_SCSI, DMA_CSR);
243 }
244 switch (esp->dmarev) {
245 case dvmahme:
246 dma_write32(DMA_RESET_FAS366, DMA_CSR);
247 dma_write32(DMA_RST_SCSI, DMA_CSR);
248
249 esp->prev_hme_dmacsr = (DMA_PARITY_OFF | DMA_2CLKS |
250 DMA_SCSI_DISAB | DMA_INT_ENAB);
251
252 esp->prev_hme_dmacsr &= ~(DMA_ENABLE | DMA_ST_WRITE |
253 DMA_BRST_SZ);
254
255 if (can_do_burst64)
256 esp->prev_hme_dmacsr |= DMA_BRST64;
257 else if (can_do_burst32)
258 esp->prev_hme_dmacsr |= DMA_BRST32;
259
260 if (can_do_sbus64) {
261 esp->prev_hme_dmacsr |= DMA_SCSI_SBUS64;
262 sbus_set_sbus64(&op->dev, esp->bursts);
263 }
264
265 lim = 1000;
266 while (dma_read32(DMA_CSR) & DMA_PEND_READ) {
267 if (--lim == 0) {
268 printk(KERN_ALERT PFX "esp%d: DMA_PEND_READ "
269 "will not clear!\n",
270 esp->host->unique_id);
271 break;
272 }
273 udelay(1);
274 }
275
276 dma_write32(0, DMA_CSR);
277 dma_write32(esp->prev_hme_dmacsr, DMA_CSR);
278
279 dma_write32(0, DMA_ADDR);
280 break;
281
282 case dvmarev2:
283 if (esp->rev != ESP100) {
284 val = dma_read32(DMA_CSR);
285 dma_write32(val | DMA_3CLKS, DMA_CSR);
286 }
287 break;
288
289 case dvmarev3:
290 val = dma_read32(DMA_CSR);
291 val &= ~DMA_3CLKS;
292 val |= DMA_2CLKS;
293 if (can_do_burst32) {
294 val &= ~DMA_BRST_SZ;
295 val |= DMA_BRST32;
296 }
297 dma_write32(val, DMA_CSR);
298 break;
299
300 case dvmaesc1:
301 val = dma_read32(DMA_CSR);
302 val |= DMA_ADD_ENABLE;
303 val &= ~DMA_BCNT_ENAB;
304 if (!can_do_burst32 && can_do_burst16) {
305 val |= DMA_ESC_BURST;
306 } else {
307 val &= ~(DMA_ESC_BURST);
308 }
309 dma_write32(val, DMA_CSR);
310 break;
311
312 default:
313 break;
314 }
315
316 /* Enable interrupts. */
317 val = dma_read32(DMA_CSR);
318 dma_write32(val | DMA_INT_ENAB, DMA_CSR);
319 }
320
sbus_esp_dma_drain(struct esp * esp)321 static void sbus_esp_dma_drain(struct esp *esp)
322 {
323 u32 csr;
324 int lim;
325
326 if (esp->dmarev == dvmahme)
327 return;
328
329 csr = dma_read32(DMA_CSR);
330 if (!(csr & DMA_FIFO_ISDRAIN))
331 return;
332
333 if (esp->dmarev != dvmarev3 && esp->dmarev != dvmaesc1)
334 dma_write32(csr | DMA_FIFO_STDRAIN, DMA_CSR);
335
336 lim = 1000;
337 while (dma_read32(DMA_CSR) & DMA_FIFO_ISDRAIN) {
338 if (--lim == 0) {
339 printk(KERN_ALERT PFX "esp%d: DMA will not drain!\n",
340 esp->host->unique_id);
341 break;
342 }
343 udelay(1);
344 }
345 }
346
sbus_esp_dma_invalidate(struct esp * esp)347 static void sbus_esp_dma_invalidate(struct esp *esp)
348 {
349 if (esp->dmarev == dvmahme) {
350 dma_write32(DMA_RST_SCSI, DMA_CSR);
351
352 esp->prev_hme_dmacsr = ((esp->prev_hme_dmacsr |
353 (DMA_PARITY_OFF | DMA_2CLKS |
354 DMA_SCSI_DISAB | DMA_INT_ENAB)) &
355 ~(DMA_ST_WRITE | DMA_ENABLE));
356
357 dma_write32(0, DMA_CSR);
358 dma_write32(esp->prev_hme_dmacsr, DMA_CSR);
359
360 /* This is necessary to avoid having the SCSI channel
361 * engine lock up on us.
362 */
363 dma_write32(0, DMA_ADDR);
364 } else {
365 u32 val;
366 int lim;
367
368 lim = 1000;
369 while ((val = dma_read32(DMA_CSR)) & DMA_PEND_READ) {
370 if (--lim == 0) {
371 printk(KERN_ALERT PFX "esp%d: DMA will not "
372 "invalidate!\n", esp->host->unique_id);
373 break;
374 }
375 udelay(1);
376 }
377
378 val &= ~(DMA_ENABLE | DMA_ST_WRITE | DMA_BCNT_ENAB);
379 val |= DMA_FIFO_INV;
380 dma_write32(val, DMA_CSR);
381 val &= ~DMA_FIFO_INV;
382 dma_write32(val, DMA_CSR);
383 }
384 }
385
sbus_esp_send_dma_cmd(struct esp * esp,u32 addr,u32 esp_count,u32 dma_count,int write,u8 cmd)386 static void sbus_esp_send_dma_cmd(struct esp *esp, u32 addr, u32 esp_count,
387 u32 dma_count, int write, u8 cmd)
388 {
389 u32 csr;
390
391 BUG_ON(!(cmd & ESP_CMD_DMA));
392
393 sbus_esp_write8(esp, (esp_count >> 0) & 0xff, ESP_TCLOW);
394 sbus_esp_write8(esp, (esp_count >> 8) & 0xff, ESP_TCMED);
395 if (esp->rev == FASHME) {
396 sbus_esp_write8(esp, (esp_count >> 16) & 0xff, FAS_RLO);
397 sbus_esp_write8(esp, 0, FAS_RHI);
398
399 scsi_esp_cmd(esp, cmd);
400
401 csr = esp->prev_hme_dmacsr;
402 csr |= DMA_SCSI_DISAB | DMA_ENABLE;
403 if (write)
404 csr |= DMA_ST_WRITE;
405 else
406 csr &= ~DMA_ST_WRITE;
407 esp->prev_hme_dmacsr = csr;
408
409 dma_write32(dma_count, DMA_COUNT);
410 dma_write32(addr, DMA_ADDR);
411 dma_write32(csr, DMA_CSR);
412 } else {
413 csr = dma_read32(DMA_CSR);
414 csr |= DMA_ENABLE;
415 if (write)
416 csr |= DMA_ST_WRITE;
417 else
418 csr &= ~DMA_ST_WRITE;
419 dma_write32(csr, DMA_CSR);
420 if (esp->dmarev == dvmaesc1) {
421 u32 end = PAGE_ALIGN(addr + dma_count + 16U);
422 dma_write32(end - addr, DMA_COUNT);
423 }
424 dma_write32(addr, DMA_ADDR);
425
426 scsi_esp_cmd(esp, cmd);
427 }
428
429 }
430
sbus_esp_dma_error(struct esp * esp)431 static int sbus_esp_dma_error(struct esp *esp)
432 {
433 u32 csr = dma_read32(DMA_CSR);
434
435 if (csr & DMA_HNDL_ERROR)
436 return 1;
437
438 return 0;
439 }
440
441 static const struct esp_driver_ops sbus_esp_ops = {
442 .esp_write8 = sbus_esp_write8,
443 .esp_read8 = sbus_esp_read8,
444 .irq_pending = sbus_esp_irq_pending,
445 .reset_dma = sbus_esp_reset_dma,
446 .dma_drain = sbus_esp_dma_drain,
447 .dma_invalidate = sbus_esp_dma_invalidate,
448 .send_dma_cmd = sbus_esp_send_dma_cmd,
449 .dma_error = sbus_esp_dma_error,
450 };
451
esp_sbus_probe_one(struct platform_device * op,struct platform_device * espdma,int hme)452 static int esp_sbus_probe_one(struct platform_device *op,
453 struct platform_device *espdma, int hme)
454 {
455 const struct scsi_host_template *tpnt = &scsi_esp_template;
456 struct Scsi_Host *host;
457 struct esp *esp;
458 int err;
459
460 host = scsi_host_alloc(tpnt, sizeof(struct esp));
461
462 err = -ENOMEM;
463 if (!host)
464 goto fail;
465
466 host->max_id = (hme ? 16 : 8);
467 esp = shost_priv(host);
468
469 esp->host = host;
470 esp->dev = &op->dev;
471 esp->ops = &sbus_esp_ops;
472
473 if (hme)
474 esp->flags |= ESP_FLAG_WIDE_CAPABLE;
475
476 err = esp_sbus_setup_dma(esp, espdma);
477 if (err < 0)
478 goto fail_unlink;
479
480 err = esp_sbus_map_regs(esp, hme);
481 if (err < 0)
482 goto fail_unlink;
483
484 err = esp_sbus_map_command_block(esp);
485 if (err < 0)
486 goto fail_unmap_regs;
487
488 err = esp_sbus_register_irq(esp);
489 if (err < 0)
490 goto fail_unmap_command_block;
491
492 esp_sbus_get_props(esp, espdma);
493
494 /* Before we try to touch the ESP chip, ESC1 dma can
495 * come up with the reset bit set, so make sure that
496 * is clear first.
497 */
498 if (esp->dmarev == dvmaesc1) {
499 u32 val = dma_read32(DMA_CSR);
500
501 dma_write32(val & ~DMA_RST_SCSI, DMA_CSR);
502 }
503
504 dev_set_drvdata(&op->dev, esp);
505
506 err = scsi_esp_register(esp);
507 if (err)
508 goto fail_free_irq;
509
510 return 0;
511
512 fail_free_irq:
513 free_irq(host->irq, esp);
514 fail_unmap_command_block:
515 dma_free_coherent(&op->dev, 16,
516 esp->command_block,
517 esp->command_block_dma);
518 fail_unmap_regs:
519 of_iounmap(&op->resource[(hme ? 1 : 0)], esp->regs, SBUS_ESP_REG_SIZE);
520 fail_unlink:
521 scsi_host_put(host);
522 fail:
523 return err;
524 }
525
esp_sbus_probe(struct platform_device * op)526 static int esp_sbus_probe(struct platform_device *op)
527 {
528 struct device_node *dma_node = NULL;
529 struct device_node *dp = op->dev.of_node;
530 struct platform_device *dma_of = NULL;
531 int hme = 0;
532 int ret;
533
534 if (of_node_name_eq(dp->parent, "espdma") ||
535 of_node_name_eq(dp->parent, "dma"))
536 dma_node = dp->parent;
537 else if (of_node_name_eq(dp, "SUNW,fas")) {
538 dma_node = op->dev.of_node;
539 hme = 1;
540 }
541 if (dma_node)
542 dma_of = of_find_device_by_node(dma_node);
543 if (!dma_of)
544 return -ENODEV;
545
546 ret = esp_sbus_probe_one(op, dma_of, hme);
547 if (ret)
548 put_device(&dma_of->dev);
549
550 return ret;
551 }
552
esp_sbus_remove(struct platform_device * op)553 static int esp_sbus_remove(struct platform_device *op)
554 {
555 struct esp *esp = dev_get_drvdata(&op->dev);
556 struct platform_device *dma_of = esp->dma;
557 unsigned int irq = esp->host->irq;
558 bool is_hme;
559 u32 val;
560
561 scsi_esp_unregister(esp);
562
563 /* Disable interrupts. */
564 val = dma_read32(DMA_CSR);
565 dma_write32(val & ~DMA_INT_ENAB, DMA_CSR);
566
567 free_irq(irq, esp);
568
569 is_hme = (esp->dmarev == dvmahme);
570
571 dma_free_coherent(&op->dev, 16,
572 esp->command_block,
573 esp->command_block_dma);
574 of_iounmap(&op->resource[(is_hme ? 1 : 0)], esp->regs,
575 SBUS_ESP_REG_SIZE);
576 of_iounmap(&dma_of->resource[0], esp->dma_regs,
577 resource_size(&dma_of->resource[0]));
578
579 scsi_host_put(esp->host);
580
581 dev_set_drvdata(&op->dev, NULL);
582
583 put_device(&dma_of->dev);
584
585 return 0;
586 }
587
588 static const struct of_device_id esp_match[] = {
589 {
590 .name = "SUNW,esp",
591 },
592 {
593 .name = "SUNW,fas",
594 },
595 {
596 .name = "esp",
597 },
598 {},
599 };
600 MODULE_DEVICE_TABLE(of, esp_match);
601
602 static struct platform_driver esp_sbus_driver = {
603 .driver = {
604 .name = "esp",
605 .of_match_table = esp_match,
606 },
607 .probe = esp_sbus_probe,
608 .remove = esp_sbus_remove,
609 };
610 module_platform_driver(esp_sbus_driver);
611
612 MODULE_DESCRIPTION("Sun ESP SCSI driver");
613 MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
614 MODULE_LICENSE("GPL");
615 MODULE_VERSION(DRV_VERSION);
616