summaryrefslogtreecommitdiffstats
path: root/drivers/scsi/mac_esp.c
blob: 4ceeace804533c42b287aa9c54a3f952176dab9f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
/* mac_esp.c: ESP front-end for Macintosh Quadra systems.
 *
 * Adapted from jazz_esp.c and the old mac_esp.c.
 *
 * The pseudo DMA algorithm is based on the one used in NetBSD.
 * See sys/arch/mac68k/obio/esp.c for some background information.
 *
 * Copyright (C) 2007-2008 Finn Thain
 */

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/scatterlist.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/nubus.h>
#include <linux/slab.h>

#include <asm/irq.h>
#include <asm/dma.h>
#include <asm/macints.h>
#include <asm/macintosh.h>
#include <asm/mac_via.h>

#include <scsi/scsi_host.h>

#include "esp_scsi.h"

#define DRV_MODULE_NAME     "mac_esp"
#define PFX                 DRV_MODULE_NAME ": "
#define DRV_VERSION         "1.000"
#define DRV_MODULE_RELDATE  "Sept 15, 2007"

#define MAC_ESP_IO_BASE          0x50F00000
#define MAC_ESP_REGS_QUADRA      (MAC_ESP_IO_BASE + 0x10000)
#define MAC_ESP_REGS_QUADRA2     (MAC_ESP_IO_BASE + 0xF000)
#define MAC_ESP_REGS_QUADRA3     (MAC_ESP_IO_BASE + 0x18000)
#define MAC_ESP_REGS_SPACING     0x402
#define MAC_ESP_PDMA_REG         0xF9800024
#define MAC_ESP_PDMA_REG_SPACING 0x4
#define MAC_ESP_PDMA_IO_OFFSET   0x100

#define esp_read8(REG)		mac_esp_read8(esp, REG)
#define esp_write8(VAL, REG)	mac_esp_write8(esp, VAL, REG)

struct mac_esp_priv {
	struct esp *esp;
	void __iomem *pdma_regs;
	void __iomem *pdma_io;
	int error;
};
static struct esp *esp_chips[2];

#define MAC_ESP_GET_PRIV(esp) ((struct mac_esp_priv *) \
			       platform_get_drvdata((struct platform_device *) \
						    (esp->dev)))

static inline void mac_esp_write8(struct esp *esp, u8 val, unsigned long reg)
{
	nubus_writeb(val, esp->regs + reg * 16);
}

static inline u8 mac_esp_read8(struct esp *esp, unsigned long reg)
{
	return nubus_readb(esp->regs + reg * 16);
}

/* For pseudo DMA and PIO we need the virtual address
 * so this address mapping is the identity mapping.
 */

static dma_addr_t mac_esp_map_single(struct esp *esp, void *buf,
				     size_t sz, int dir)
{
	return (dma_addr_t)buf;
}

static int mac_esp_map_sg(struct esp *esp, struct scatterlist *sg,
			  int num_sg, int dir)
{
	int i;

	for (i = 0; i < num_sg; i++)
		sg[i].dma_address = (u32)sg_virt(&sg[i]);
	return num_sg;
}

static void mac_esp_unmap_single(struct esp *esp, dma_addr_t addr,
				 size_t sz, int dir)
{
	/* Nothing to do. */
}

static void mac_esp_unmap_sg(struct esp *esp, struct scatterlist *sg,
			     int num_sg, int dir)
{
	/* Nothing to do. */
}

static void mac_esp_reset_dma(struct esp *esp)
{
	/* Nothing to do. */
}

static void mac_esp_dma_drain(struct esp *esp)
{
	/* Nothing to do. */
}

static void mac_esp_dma_invalidate(struct esp *esp)
{
	/* Nothing to do. */
}

static int mac_esp_dma_error(struct esp *esp)
{
	return MAC_ESP_GET_PRIV(esp)->error;
}

static inline int mac_esp_wait_for_empty_fifo(struct esp *esp)
{
	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
	int i = 500000;

	do {
		if (!(esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES))
			return 0;

		if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
			return 1;

		udelay(2);
	} while (--i);

	printk(KERN_ERR PFX "FIFO is not empty (sreg %02x)\n",
	       esp_read8(ESP_STATUS));
	mep->error = 1;
	return 1;
}

static inline int mac_esp_wait_for_dreq(struct esp *esp)
{
	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
	int i = 500000;

	do {
		if (mep->pdma_regs == NULL) {
			if (via2_scsi_drq_pending())
				return 0;
		} else {
			if (nubus_readl(mep->pdma_regs) & 0x200)
				return 0;
		}

		if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
			return 1;

		udelay(2);
	} while (--i);

	printk(KERN_ERR PFX "PDMA timeout (sreg %02x)\n",
	       esp_read8(ESP_STATUS));
	mep->error = 1;
	return 1;
}

#define MAC_ESP_PDMA_LOOP(operands) \
	asm volatile ( \
	     "       tstw %1                   \n" \
	     "       jbeq 20f                  \n" \
	     "1:     movew " operands "        \n" \
	     "2:     movew " operands "        \n" \
	     "3:     movew " operands "        \n" \
	     "4:     movew " operands "        \n" \
	     "5:     movew " operands "        \n" \
	     "6:     movew " operands "        \n" \
	     "7:     movew " operands "        \n" \
	     "8:     movew " operands "        \n" \
	     "9:     movew " operands "        \n" \
	     "10:    movew " operands "        \n" \
	     "11:    movew " operands "        \n" \
	     "12:    movew " operands "        \n" \
	     "13:    movew " operands "        \n" \
	     "14:    movew " operands "        \n" \
	     "15:    movew " operands "        \n" \
	     "16:    movew " operands "        \n" \
	     "       subqw #1,%1               \n" \
	     "       jbne 1b                   \n" \
	     "20:    tstw %2                   \n" \
	     "       jbeq 30f                  \n" \
	     "21:    movew " operands "        \n" \
	     "       subqw #1,%2               \n" \
	     "       jbne 21b                  \n" \
	     "30:    tstw %3                   \n" \
	     "       jbeq 40f                  \n" \
	     "31:    moveb " operands "        \n" \
	     "32:    nop                       \n" \
	     "40:                              \n" \
	     "                                 \n" \
	     "       .section __ex_table,\"a\" \n" \
	     "       .align  4                 \n" \
	     "       .long   1b,40b            \n" \
	     "       .long   2b,40b            \n" \
	     "       .long   3b,40b            \n" \
	     "       .long   4b,40b            \n" \
	     "       .long   5b,40b            \n" \
	     "       .long   6b,40b            \n" \
	     "       .long   7b,40b            \n" \
	     "       .long   8b,40b            \n" \
	     "       .long   9b,40b            \n" \
	     "       .long  10b,40b            \n" \
	     "       .long  11b,40b            \n" \
	     "       .long  12b,40b            \n" \
	     "       .long  13b,40b            \n" \
	     "       .long  14b,40b            \n" \
	     "       .long  15b,40b            \n" \
	     "       .long  16b,40b            \n" \
	     "       .long  21b,40b            \n" \
	     "       .long  31b,40b            \n" \
	     "       .long  32b,40b            \n" \
	     "       .previous                 \n" \
	     : "+a" (addr), "+r" (count32), "+r" (count2) \
	     : "g" (count1), "a" (mep->pdma_io))

static void mac_esp_send_pdma_cmd(struct esp *esp, u32 addr, u32 esp_count,
				  u32 dma_count, int write, u8 cmd)
{
	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);

	mep->error = 0;

	if (!write)
		scsi_esp_cmd(esp, ESP_CMD_FLUSH);

	esp_write8((esp_count >> 0) & 0xFF, ESP_TCLOW);
	esp_write8((esp_count >> 8) & 0xFF, ESP_TCMED);

	scsi_esp_cmd(esp, cmd);

	do {
		unsigned int count32 = esp_count >> 5;
		unsigned int count2 = (esp_count & 0x1F) >> 1;
		unsigned int count1 = esp_count & 1;
		unsigned int start_addr = addr;

		if (mac_esp_wait_for_dreq(esp))
			break;

		if (write) {
			MAC_ESP_PDMA_LOOP("%4@,%0@+");

			esp_count -= addr - start_addr;
		} else {
			unsigned int n;

			MAC_ESP_PDMA_LOOP("%0@+,%4@");

			if (mac_esp_wait_for_empty_fifo(esp))
				break;

			n = (esp_read8(ESP_TCMED) << 8) + esp_read8(ESP_TCLOW);
			addr = start_addr + esp_count - n;
			esp_count = n;
		}
	} while (esp_count);
}

/*
 * Programmed IO routines follow.
 */

static inline unsigned int mac_esp_wait_for_fifo(struct esp *esp)
{
	int i = 500000;

	do {
		unsigned int fbytes = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;

		if (fbytes)
			return fbytes;

		udelay(2);
	} while (--i);

	printk(KERN_ERR PFX "FIFO is empty (sreg %02x)\n",
	       esp_read8(ESP_STATUS));
	return 0;
}

static inline int mac_esp_wait_for_intr(struct esp *esp)
{
	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
	int i = 500000;

	do {
		esp->sreg = esp_read8(ESP_STATUS);
		if (esp->sreg & ESP_STAT_INTR)
			return 0;

		udelay(2);
	} while (--i);

	printk(KERN_ERR PFX "IRQ timeout (sreg %02x)\n", esp->sreg);
	mep->error = 1;
	return 1;
}

#define MAC_ESP_PIO_LOOP(operands, reg1) \
	asm volatile ( \
	     "1:     moveb " operands " \n" \
	     "       subqw #1,%1        \n" \
	     "       jbne 1b            \n" \
	     : "+a" (addr), "+r" (reg1) \
	     : "a" (fifo))

#define MAC_ESP_PIO_FILL(operands, reg1) \
	asm volatile ( \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       subqw #8,%1        \n" \
	     "       subqw #8,%1        \n" \
	     : "+a" (addr), "+r" (reg1) \
	     : "a" (fifo))

#define MAC_ESP_FIFO_SIZE 16

static void mac_esp_send_pio_cmd(struct esp *esp, u32 addr, u32 esp_count,
				 u32 dma_count, int write, u8 cmd)
{
	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
	u8 *fifo = esp->regs + ESP_FDATA * 16;

	cmd &= ~ESP_CMD_DMA;
	mep->error = 0;

	if (write) {
		scsi_esp_cmd(esp, cmd);

		while (1) {
			unsigned int n;

			n = mac_esp_wait_for_fifo(esp);
			if (!n)
				break;

			if (n > esp_count)
				n = esp_count;
			esp_count -= n;

			MAC_ESP_PIO_LOOP("%2@,%0@+", n);

			if (!esp_count)
				break;

			if (mac_esp_wait_for_intr(esp))
				break;

			if (((esp->sreg & ESP_STAT_PMASK) != ESP_DIP) &&
			    ((esp->sreg & ESP_STAT_PMASK) != ESP_MIP))
				break;

			esp->ireg = esp_read8(ESP_INTRPT);
			if ((esp->ireg & (ESP_INTR_DC | ESP_INTR_BSERV)) !=
			    ESP_INTR_BSERV)
				break;

			scsi_esp_cmd(esp, ESP_CMD_TI);
		}
	} else {
		scsi_esp_cmd(esp, ESP_CMD_FLUSH);

		if (esp_count >= MAC_ESP_FIFO_SIZE)
			MAC_ESP_PIO_FILL("%0@+,%2@", esp_count);
		else
			MAC_ESP_PIO_LOOP("%0@+,%2@", esp_count);

		scsi_esp_cmd(esp, cmd);

		while (esp_count) {
			unsigned int n;

			if (mac_esp_wait_for_intr(esp))
				break;

			if (((esp->sreg & ESP_STAT_PMASK) != ESP_DOP) &&
			    ((esp->sreg & ESP_STAT_PMASK) != ESP_MOP))
				break;

			esp->ireg = esp_read8(ESP_INTRPT);
			if ((esp->ireg & (ESP_INTR_DC | ESP_INTR_BSERV)) !=
			    ESP_INTR_BSERV)
				break;

			n = MAC_ESP_FIFO_SIZE -
			    (esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES);
			if (n > esp_count)
				n = esp_count;

			if (n == MAC_ESP_FIFO_SIZE) {
				MAC_ESP_PIO_FILL("%0@+,%2@", esp_count);
			} else {
				esp_count -= n;
				MAC_ESP_PIO_LOOP("%0@+,%2@", n);
			}

			scsi_esp_cmd(esp, ESP_CMD_TI);
		}
	}
}

static int mac_esp_irq_pending(struct esp *esp)
{
	if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
		return 1;
	return 0;
}

static u32 mac_esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len)
{
	return dma_len > 0xFFFF ? 0xFFFF : dma_len;
}

static irqreturn_t mac_scsi_esp_intr(int irq, void *dev_id)
{
	int got_intr;

	/*
	 * This is an edge triggered IRQ, so we have to be careful to
	 * avoid missing a transition when it is shared by two ESP devices.
	 */

	do {
		got_intr = 0;
		if (esp_chips[0] &&
		    (mac_esp_read8(esp_chips[0], ESP_STATUS) & ESP_STAT_INTR)) {
			(void)scsi_esp_intr(irq, esp_chips[0]);
			got_intr = 1;
		}
		if (esp_chips[1] &&
		    (mac_esp_read8(esp_chips[1], ESP_STATUS) & ESP_STAT_INTR)) {
			(void)scsi_esp_intr(irq, esp_chips[1]);
			got_intr = 1;
		}
	} while (got_intr);

	return IRQ_HANDLED;
}

static struct esp_driver_ops mac_esp_ops = {
	.esp_write8       = mac_esp_write8,
	.esp_read8        = mac_esp_read8,
	.map_single       = mac_esp_map_single,
	.map_sg           = mac_esp_map_sg,
	.unmap_single     = mac_esp_unmap_single,
	.unmap_sg         = mac_esp_unmap_sg,
	.irq_pending      = mac_esp_irq_pending,
	.dma_length_limit = mac_esp_dma_length_limit,
	.reset_dma        = mac_esp_reset_dma,
	.dma_drain        = mac_esp_dma_drain,
	.dma_invalidate   = mac_esp_dma_invalidate,
	.send_dma_cmd     = mac_esp_send_pdma_cmd,
	.dma_error        = mac_esp_dma_error,
};

static int __devinit esp_mac_probe(struct platform_device *dev)
{
	struct scsi_host_template *tpnt = &scsi_esp_template;
	struct Scsi_Host *host;
	struct esp *esp;
	int err;
	struct mac_esp_priv *mep;

	if (!MACH_IS_MAC)
		return -ENODEV;

	if (dev->id > 1)
		return -ENODEV;

	host = scsi_host_alloc(tpnt, sizeof(struct esp));

	err = -ENOMEM;
	if (!host)
		goto fail;

	host->max_id = 8;
	host->use_clustering = DISABLE_CLUSTERING;
	esp = shost_priv(host);

	esp->host = host;
	esp->dev = dev;

	esp->command_block = kzalloc(16, GFP_KERNEL);
	if (!esp->command_block)
		goto fail_unlink;
	esp->command_block_dma = (dma_addr_t)esp->command_block;

	esp->scsi_id = 7;
	host->this_id = esp->scsi_id;
	esp->scsi_id_mask = 1 << esp->scsi_id;

	mep = kzalloc(sizeof(struct mac_esp_priv), GFP_KERNEL);
	if (!mep)
		goto fail_free_command_block;
	mep->esp = esp;
	platform_set_drvdata(dev, mep);

	switch (macintosh_config->scsi_type) {
	case MAC_SCSI_QUADRA:
		esp->cfreq     = 16500000;
		esp->regs      = (void __iomem *)MAC_ESP_REGS_QUADRA;
		mep->pdma_io   = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
		mep->pdma_regs = NULL;
		break;
	case MAC_SCSI_QUADRA2:
		esp->cfreq     = 25000000;
		esp->regs      = (void __iomem *)(MAC_ESP_REGS_QUADRA2 +
				 dev->id * MAC_ESP_REGS_SPACING);
		mep->pdma_io   = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
		mep->pdma_regs = (void __iomem *)(MAC_ESP_PDMA_REG +
				 dev->id * MAC_ESP_PDMA_REG_SPACING);
		nubus_writel(0x1d1, mep->pdma_regs);
		break;
	case MAC_SCSI_QUADRA3:
		/* These quadras have a real DMA controller (the PSC) but we
		 * don't know how to drive it so we must use PIO instead.
		 */
		esp->cfreq     = 25000000;
		esp->regs      = (void __iomem *)MAC_ESP_REGS_QUADRA3;
		mep->pdma_io   = NULL;
		mep->pdma_regs = NULL;
		break;
	}

	esp->ops = &mac_esp_ops;
	if (mep->pdma_io == NULL) {
		printk(KERN_INFO PFX "using PIO for controller %d\n", dev->id);
		esp_write8(0, ESP_TCLOW);
		esp_write8(0, ESP_TCMED);
		esp->flags = ESP_FLAG_DISABLE_SYNC;
		mac_esp_ops.send_dma_cmd = mac_esp_send_pio_cmd;
	} else {
		printk(KERN_INFO PFX "using PDMA for controller %d\n", dev->id);
	}

	host->irq = IRQ_MAC_SCSI;
	esp_chips[dev->id] = esp;
	mb();
	if (esp_chips[!dev->id] == NULL) {
		err = request_irq(host->irq, mac_scsi_esp_intr, 0,
		                  "Mac ESP", NULL);
		if (err < 0) {
			esp_chips[dev->id] = NULL;
			goto fail_free_priv;
		}
	}

	err = scsi_esp_register(esp, &dev->dev);
	if (err)
		goto fail_free_irq;

	return 0;

fail_free_irq:
	if (esp_chips[!dev->id] == NULL)
		free_irq(host->irq, esp);
fail_free_priv:
	kfree(mep);
fail_free_command_block:
	kfree(esp->command_block);
fail_unlink:
	scsi_host_put(host);
fail:
	return err;
}

static int __devexit esp_mac_remove(struct platform_device *dev)
{
	struct mac_esp_priv *mep = platform_get_drvdata(dev);
	struct esp *esp = mep->esp;
	unsigned int irq = esp->host->irq;

	scsi_esp_unregister(esp);

	esp_chips[dev->id] = NULL;
	if (!(esp_chips[0] || esp_chips[1]))
		free_irq(irq, NULL);

	kfree(mep);

	kfree(esp->command_block);

	scsi_host_put(esp->host);

	return 0;
}

static struct platform_driver esp_mac_driver = {
	.probe    = esp_mac_probe,
	.remove   = __devexit_p(esp_mac_remove),
	.driver   = {
		.name	= DRV_MODULE_NAME,
		.owner	= THIS_MODULE,
	},
};

static int __init mac_esp_init(void)
{
	return platform_driver_register(&esp_mac_driver);
}

static void __exit mac_esp_exit(void)
{
	platform_driver_unregister(&esp_mac_driver);
}

MODULE_DESCRIPTION("Mac ESP SCSI driver");
MODULE_AUTHOR("Finn Thain <fthain@telegraphics.com.au>");
MODULE_LICENSE("GPL v2");
MODULE_VERSION(DRV_VERSION);
MODULE_ALIAS("platform:" DRV_MODULE_NAME);

module_init(mac_esp_init);
module_exit(mac_esp_exit);
OpenPOWER on IntegriCloud