summaryrefslogtreecommitdiffstats
path: root/drivers/ide/ide-dma.c
blob: a0b8cab1d9a682249200fce35bc5ea5c8223079f (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
/*
 *  IDE DMA support (including IDE PCI BM-DMA).
 *
 *  Copyright (C) 1995-1998   Mark Lord
 *  Copyright (C) 1999-2000   Andre Hedrick <andre@linux-ide.org>
 *  Copyright (C) 2004, 2007  Bartlomiej Zolnierkiewicz
 *
 *  May be copied or modified under the terms of the GNU General Public License
 *
 *  DMA is supported for all IDE devices (disk drives, cdroms, tapes, floppies).
 */

/*
 *  Special Thanks to Mark for his Six years of work.
 */

/*
 * Thanks to "Christopher J. Reimer" <reimer@doe.carleton.ca> for
 * fixing the problem with the BIOS on some Acer motherboards.
 *
 * Thanks to "Benoit Poulot-Cazajous" <poulot@chorus.fr> for testing
 * "TX" chipset compatibility and for providing patches for the "TX" chipset.
 *
 * Thanks to Christian Brunner <chb@muc.de> for taking a good first crack
 * at generic DMA -- his patches were referred to when preparing this code.
 *
 * Most importantly, thanks to Robert Bringman <rob@mars.trion.com>
 * for supplying a Promise UDMA board & WD UDMA drive for this work!
 */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/ide.h>
#include <linux/scatterlist.h>
#include <linux/dma-mapping.h>

static const struct drive_list_entry drive_whitelist[] = {
	{ "Micropolis 2112A"	,       NULL		},
	{ "CONNER CTMA 4000"	,       NULL		},
	{ "CONNER CTT8000-A"	,       NULL		},
	{ "ST34342A"		,	NULL		},
	{ NULL			,	NULL		}
};

static const struct drive_list_entry drive_blacklist[] = {
	{ "WDC AC11000H"	,	NULL 		},
	{ "WDC AC22100H"	,	NULL 		},
	{ "WDC AC32500H"	,	NULL 		},
	{ "WDC AC33100H"	,	NULL 		},
	{ "WDC AC31600H"	,	NULL 		},
	{ "WDC AC32100H"	,	"24.09P07"	},
	{ "WDC AC23200L"	,	"21.10N21"	},
	{ "Compaq CRD-8241B"	,	NULL 		},
	{ "CRD-8400B"		,	NULL 		},
	{ "CRD-8480B",			NULL 		},
	{ "CRD-8482B",			NULL 		},
	{ "CRD-84"		,	NULL 		},
	{ "SanDisk SDP3B"	,	NULL 		},
	{ "SanDisk SDP3B-64"	,	NULL 		},
	{ "SANYO CD-ROM CRD"	,	NULL 		},
	{ "HITACHI CDR-8"	,	NULL 		},
	{ "HITACHI CDR-8335"	,	NULL 		},
	{ "HITACHI CDR-8435"	,	NULL 		},
	{ "Toshiba CD-ROM XM-6202B"	,	NULL 		},
	{ "TOSHIBA CD-ROM XM-1702BC",	NULL 		},
	{ "CD-532E-A"		,	NULL 		},
	{ "E-IDE CD-ROM CR-840",	NULL 		},
	{ "CD-ROM Drive/F5A",	NULL 		},
	{ "WPI CDD-820",		NULL 		},
	{ "SAMSUNG CD-ROM SC-148C",	NULL 		},
	{ "SAMSUNG CD-ROM SC",	NULL 		},
	{ "ATAPI CD-ROM DRIVE 40X MAXIMUM",	NULL 		},
	{ "_NEC DV5800A",               NULL            },
	{ "SAMSUNG CD-ROM SN-124",	"N001" },
	{ "Seagate STT20000A",		NULL  },
	{ "CD-ROM CDR_U200",		"1.09" },
	{ NULL			,	NULL		}

};

/**
 *	ide_dma_intr	-	IDE DMA interrupt handler
 *	@drive: the drive the interrupt is for
 *
 *	Handle an interrupt completing a read/write DMA transfer on an
 *	IDE device
 */

ide_startstop_t ide_dma_intr(ide_drive_t *drive)
{
	ide_hwif_t *hwif = drive->hwif;
	struct ide_cmd *cmd = &hwif->cmd;
	u8 stat = 0, dma_stat = 0;

	drive->waiting_for_dma = 0;
	dma_stat = hwif->dma_ops->dma_end(drive);
	ide_dma_unmap_sg(drive, cmd);
	stat = hwif->tp_ops->read_status(hwif);

	if (OK_STAT(stat, DRIVE_READY, drive->bad_wstat | ATA_DRQ)) {
		if (!dma_stat) {
			if ((cmd->tf_flags & IDE_TFLAG_FS) == 0)
				ide_finish_cmd(drive, cmd, stat);
			else
				ide_complete_rq(drive, 0,
						cmd->rq->nr_sectors << 9);
			return ide_stopped;
		}
		printk(KERN_ERR "%s: %s: bad DMA status (0x%02x)\n",
			drive->name, __func__, dma_stat);
	}
	return ide_error(drive, "dma_intr", stat);
}

int ide_dma_good_drive(ide_drive_t *drive)
{
	return ide_in_drive_list(drive->id, drive_whitelist);
}

/**
 *	ide_dma_map_sg	-	map IDE scatter gather for DMA I/O
 *	@drive: the drive to map the DMA table for
 *	@cmd: command
 *
 *	Perform the DMA mapping magic necessary to access the source or
 *	target buffers of a request via DMA.  The lower layers of the
 *	kernel provide the necessary cache management so that we can
 *	operate in a portable fashion.
 */

static int ide_dma_map_sg(ide_drive_t *drive, struct ide_cmd *cmd)
{
	ide_hwif_t *hwif = drive->hwif;
	struct scatterlist *sg = hwif->sg_table;
	int i;

	if (cmd->tf_flags & IDE_TFLAG_WRITE)
		cmd->sg_dma_direction = DMA_TO_DEVICE;
	else
		cmd->sg_dma_direction = DMA_FROM_DEVICE;

	i = dma_map_sg(hwif->dev, sg, cmd->sg_nents, cmd->sg_dma_direction);
	if (i) {
		cmd->orig_sg_nents = cmd->sg_nents;
		cmd->sg_nents = i;
	}

	return i;
}

/**
 *	ide_dma_unmap_sg	-	clean up DMA mapping
 *	@drive: The drive to unmap
 *
 *	Teardown mappings after DMA has completed. This must be called
 *	after the completion of each use of ide_build_dmatable and before
 *	the next use of ide_build_dmatable. Failure to do so will cause
 *	an oops as only one mapping can be live for each target at a given
 *	time.
 */

void ide_dma_unmap_sg(ide_drive_t *drive, struct ide_cmd *cmd)
{
	ide_hwif_t *hwif = drive->hwif;

	dma_unmap_sg(hwif->dev, hwif->sg_table, cmd->orig_sg_nents,
		     cmd->sg_dma_direction);
}
EXPORT_SYMBOL_GPL(ide_dma_unmap_sg);

/**
 *	ide_dma_off_quietly	-	Generic DMA kill
 *	@drive: drive to control
 *
 *	Turn off the current DMA on this IDE controller.
 */

void ide_dma_off_quietly(ide_drive_t *drive)
{
	drive->dev_flags &= ~IDE_DFLAG_USING_DMA;
	ide_toggle_bounce(drive, 0);

	drive->hwif->dma_ops->dma_host_set(drive, 0);
}
EXPORT_SYMBOL(ide_dma_off_quietly);

/**
 *	ide_dma_off	-	disable DMA on a device
 *	@drive: drive to disable DMA on
 *
 *	Disable IDE DMA for a device on this IDE controller.
 *	Inform the user that DMA has been disabled.
 */

void ide_dma_off(ide_drive_t *drive)
{
	printk(KERN_INFO "%s: DMA disabled\n", drive->name);
	ide_dma_off_quietly(drive);
}
EXPORT_SYMBOL(ide_dma_off);

/**
 *	ide_dma_on		-	Enable DMA on a device
 *	@drive: drive to enable DMA on
 *
 *	Enable IDE DMA for a device on this IDE controller.
 */

void ide_dma_on(ide_drive_t *drive)
{
	drive->dev_flags |= IDE_DFLAG_USING_DMA;
	ide_toggle_bounce(drive, 1);

	drive->hwif->dma_ops->dma_host_set(drive, 1);
}

int __ide_dma_bad_drive(ide_drive_t *drive)
{
	u16 *id = drive->id;

	int blacklist = ide_in_drive_list(id, drive_blacklist);
	if (blacklist) {
		printk(KERN_WARNING "%s: Disabling (U)DMA for %s (blacklisted)\n",
				    drive->name, (char *)&id[ATA_ID_PROD]);
		return blacklist;
	}
	return 0;
}
EXPORT_SYMBOL(__ide_dma_bad_drive);

static const u8 xfer_mode_bases[] = {
	XFER_UDMA_0,
	XFER_MW_DMA_0,
	XFER_SW_DMA_0,
};

static unsigned int ide_get_mode_mask(ide_drive_t *drive, u8 base, u8 req_mode)
{
	u16 *id = drive->id;
	ide_hwif_t *hwif = drive->hwif;
	const struct ide_port_ops *port_ops = hwif->port_ops;
	unsigned int mask = 0;

	switch (base) {
	case XFER_UDMA_0:
		if ((id[ATA_ID_FIELD_VALID] & 4) == 0)
			break;
		mask = id[ATA_ID_UDMA_MODES];
		if (port_ops && port_ops->udma_filter)
			mask &= port_ops->udma_filter(drive);
		else
			mask &= hwif->ultra_mask;

		/*
		 * avoid false cable warning from eighty_ninty_three()
		 */
		if (req_mode > XFER_UDMA_2) {
			if ((mask & 0x78) && (eighty_ninty_three(drive) == 0))
				mask &= 0x07;
		}
		break;
	case XFER_MW_DMA_0:
		mask = id[ATA_ID_MWDMA_MODES];

		/* Also look for the CF specific MWDMA modes... */
		if (ata_id_is_cfa(id) && (id[ATA_ID_CFA_MODES] & 0x38)) {
			u8 mode = ((id[ATA_ID_CFA_MODES] & 0x38) >> 3) - 1;

			mask |= ((2 << mode) - 1) << 3;
		}

		if (port_ops && port_ops->mdma_filter)
			mask &= port_ops->mdma_filter(drive);
		else
			mask &= hwif->mwdma_mask;
		break;
	case XFER_SW_DMA_0:
		mask = id[ATA_ID_SWDMA_MODES];
		if (!(mask & ATA_SWDMA2) && (id[ATA_ID_OLD_DMA_MODES] >> 8)) {
			u8 mode = id[ATA_ID_OLD_DMA_MODES] >> 8;

			/*
			 * if the mode is valid convert it to the mask
			 * (the maximum allowed mode is XFER_SW_DMA_2)
			 */
			if (mode <= 2)
				mask = (2 << mode) - 1;
		}
		mask &= hwif->swdma_mask;
		break;
	default:
		BUG();
		break;
	}

	return mask;
}

/**
 *	ide_find_dma_mode	-	compute DMA speed
 *	@drive: IDE device
 *	@req_mode: requested mode
 *
 *	Checks the drive/host capabilities and finds the speed to use for
 *	the DMA transfer.  The speed is then limited by the requested mode.
 *
 *	Returns 0 if the drive/host combination is incapable of DMA transfers
 *	or if the requested mode is not a DMA mode.
 */

u8 ide_find_dma_mode(ide_drive_t *drive, u8 req_mode)
{
	ide_hwif_t *hwif = drive->hwif;
	unsigned int mask;
	int x, i;
	u8 mode = 0;

	if (drive->media != ide_disk) {
		if (hwif->host_flags & IDE_HFLAG_NO_ATAPI_DMA)
			return 0;
	}

	for (i = 0; i < ARRAY_SIZE(xfer_mode_bases); i++) {
		if (req_mode < xfer_mode_bases[i])
			continue;
		mask = ide_get_mode_mask(drive, xfer_mode_bases[i], req_mode);
		x = fls(mask) - 1;
		if (x >= 0) {
			mode = xfer_mode_bases[i] + x;
			break;
		}
	}

	if (hwif->chipset == ide_acorn && mode == 0) {
		/*
		 * is this correct?
		 */
		if (ide_dma_good_drive(drive) &&
		    drive->id[ATA_ID_EIDE_DMA_TIME] < 150)
			mode = XFER_MW_DMA_1;
	}

	mode = min(mode, req_mode);

	printk(KERN_INFO "%s: %s mode selected\n", drive->name,
			  mode ? ide_xfer_verbose(mode) : "no DMA");

	return mode;
}
EXPORT_SYMBOL_GPL(ide_find_dma_mode);

static int ide_tune_dma(ide_drive_t *drive)
{
	ide_hwif_t *hwif = drive->hwif;
	u8 speed;

	if (ata_id_has_dma(drive->id) == 0 ||
	    (drive->dev_flags & IDE_DFLAG_NODMA))
		return 0;

	/* consult the list of known "bad" drives */
	if (__ide_dma_bad_drive(drive))
		return 0;

	if (ide_id_dma_bug(drive))
		return 0;

	if (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA)
		return config_drive_for_dma(drive);

	speed = ide_max_dma_mode(drive);

	if (!speed)
		return 0;

	if (ide_set_dma_mode(drive, speed))
		return 0;

	return 1;
}

static int ide_dma_check(ide_drive_t *drive)
{
	ide_hwif_t *hwif = drive->hwif;

	if (ide_tune_dma(drive))
		return 0;

	/* TODO: always do PIO fallback */
	if (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA)
		return -1;

	ide_set_max_pio(drive);

	return -1;
}

int ide_id_dma_bug(ide_drive_t *drive)
{
	u16 *id = drive->id;

	if (id[ATA_ID_FIELD_VALID] & 4) {
		if ((id[ATA_ID_UDMA_MODES] >> 8) &&
		    (id[ATA_ID_MWDMA_MODES] >> 8))
			goto err_out;
	} else if ((id[ATA_ID_MWDMA_MODES] >> 8) &&
		   (id[ATA_ID_SWDMA_MODES] >> 8))
		goto err_out;

	return 0;
err_out:
	printk(KERN_ERR "%s: bad DMA info in identify block\n", drive->name);
	return 1;
}

int ide_set_dma(ide_drive_t *drive)
{
	int rc;

	/*
	 * Force DMAing for the beginning of the check.
	 * Some chipsets appear to do interesting
	 * things, if not checked and cleared.
	 *   PARANOIA!!!
	 */
	ide_dma_off_quietly(drive);

	rc = ide_dma_check(drive);
	if (rc)
		return rc;

	ide_dma_on(drive);

	return 0;
}

void ide_check_dma_crc(ide_drive_t *drive)
{
	u8 mode;

	ide_dma_off_quietly(drive);
	drive->crc_count = 0;
	mode = drive->current_speed;
	/*
	 * Don't try non Ultra-DMA modes without iCRC's.  Force the
	 * device to PIO and make the user enable SWDMA/MWDMA modes.
	 */
	if (mode > XFER_UDMA_0 && mode <= XFER_UDMA_7)
		mode--;
	else
		mode = XFER_PIO_4;
	ide_set_xfer_rate(drive, mode);
	if (drive->current_speed >= XFER_SW_DMA_0)
		ide_dma_on(drive);
}

void ide_dma_lost_irq(ide_drive_t *drive)
{
	printk(KERN_ERR "%s: DMA interrupt recovery\n", drive->name);
}
EXPORT_SYMBOL_GPL(ide_dma_lost_irq);

/*
 * un-busy the port etc, and clear any pending DMA status. we want to
 * retry the current request in pio mode instead of risking tossing it
 * all away
 */
ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
{
	ide_hwif_t *hwif = drive->hwif;
	const struct ide_dma_ops *dma_ops = hwif->dma_ops;
	struct ide_cmd *cmd = &hwif->cmd;
	struct request *rq;
	ide_startstop_t ret = ide_stopped;

	/*
	 * end current dma transaction
	 */

	if (error < 0) {
		printk(KERN_WARNING "%s: DMA timeout error\n", drive->name);
		drive->waiting_for_dma = 0;
		(void)dma_ops->dma_end(drive);
		ide_dma_unmap_sg(drive, cmd);
		ret = ide_error(drive, "dma timeout error",
				hwif->tp_ops->read_status(hwif));
	} else {
		printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name);
		if (dma_ops->dma_clear)
			dma_ops->dma_clear(drive);
		printk(KERN_ERR "%s: timeout waiting for DMA\n", drive->name);
		if (dma_ops->dma_test_irq(drive) == 0) {
			ide_dump_status(drive, "DMA timeout",
					hwif->tp_ops->read_status(hwif));
			drive->waiting_for_dma = 0;
			(void)dma_ops->dma_end(drive);
			ide_dma_unmap_sg(drive, cmd);
		}
	}

	/*
	 * disable dma for now, but remember that we did so because of
	 * a timeout -- we'll reenable after we finish this next request
	 * (or rather the first chunk of it) in pio.
	 */
	drive->dev_flags |= IDE_DFLAG_DMA_PIO_RETRY;
	drive->retry_pio++;
	ide_dma_off_quietly(drive);

	/*
	 * un-busy drive etc and make sure request is sane
	 */

	rq = hwif->rq;
	if (!rq)
		goto out;

	hwif->rq = NULL;

	rq->errors = 0;

	if (!rq->bio)
		goto out;

	rq->sector = rq->bio->bi_sector;
	rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9;
	rq->hard_cur_sectors = rq->current_nr_sectors;
	rq->buffer = bio_data(rq->bio);
out:
	return ret;
}

void ide_release_dma_engine(ide_hwif_t *hwif)
{
	if (hwif->dmatable_cpu) {
		int prd_size = hwif->prd_max_nents * hwif->prd_ent_size;

		dma_free_coherent(hwif->dev, prd_size,
				  hwif->dmatable_cpu, hwif->dmatable_dma);
		hwif->dmatable_cpu = NULL;
	}
}
EXPORT_SYMBOL_GPL(ide_release_dma_engine);

int ide_allocate_dma_engine(ide_hwif_t *hwif)
{
	int prd_size;

	if (hwif->prd_max_nents == 0)
		hwif->prd_max_nents = PRD_ENTRIES;
	if (hwif->prd_ent_size == 0)
		hwif->prd_ent_size = PRD_BYTES;

	prd_size = hwif->prd_max_nents * hwif->prd_ent_size;

	hwif->dmatable_cpu = dma_alloc_coherent(hwif->dev, prd_size,
						&hwif->dmatable_dma,
						GFP_ATOMIC);
	if (hwif->dmatable_cpu == NULL) {
		printk(KERN_ERR "%s: unable to allocate PRD table\n",
			hwif->name);
		return -ENOMEM;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(ide_allocate_dma_engine);

int ide_dma_prepare(ide_drive_t *drive, struct ide_cmd *cmd)
{
	const struct ide_dma_ops *dma_ops = drive->hwif->dma_ops;

	if ((drive->dev_flags & IDE_DFLAG_USING_DMA) == 0 ||
	    (dma_ops->dma_check && dma_ops->dma_check(drive, cmd)))
		goto out;
	ide_map_sg(drive, cmd);
	if (ide_dma_map_sg(drive, cmd) == 0)
		goto out_map;
	if (dma_ops->dma_setup(drive, cmd))
		goto out_dma_unmap;
	drive->waiting_for_dma = 1;
	return 0;
out_dma_unmap:
	ide_dma_unmap_sg(drive, cmd);
out_map:
	ide_map_sg(drive, cmd);
out:
	return 1;
}
OpenPOWER on IntegriCloud