1 /*
2 * IDE DMA support (including IDE PCI BM-DMA).
3 *
4 * Copyright (C) 1995-1998 Mark Lord
5 * Copyright (C) 1999-2000 Andre Hedrick <andre@linux-ide.org>
6 * Copyright (C) 2004, 2007 Bartlomiej Zolnierkiewicz
7 *
8 * May be copied or modified under the terms of the GNU General Public License
9 *
10 * DMA is supported for all IDE devices (disk drives, cdroms, tapes, floppies).
11 */
12
13 /*
14 * Special Thanks to Mark for his Six years of work.
15 */
16
17 /*
18 * Thanks to "Christopher J. Reimer" <reimer@doe.carleton.ca> for
19 * fixing the problem with the BIOS on some Acer motherboards.
20 *
21 * Thanks to "Benoit Poulot-Cazajous" <poulot@chorus.fr> for testing
22 * "TX" chipset compatibility and for providing patches for the "TX" chipset.
23 *
24 * Thanks to Christian Brunner <chb@muc.de> for taking a good first crack
25 * at generic DMA -- his patches were referred to when preparing this code.
26 *
27 * Most importantly, thanks to Robert Bringman <rob@mars.trion.com>
28 * for supplying a Promise UDMA board & WD UDMA drive for this work!
29 */
30
31 #include <linux/types.h>
32 #include <linux/gfp.h>
33 #include <linux/kernel.h>
34 #include <linux/export.h>
35 #include <linux/ide.h>
36 #include <linux/scatterlist.h>
37 #include <linux/dma-mapping.h>
38
39 static const struct drive_list_entry drive_whitelist[] = {
40 { "Micropolis 2112A" , NULL },
41 { "CONNER CTMA 4000" , NULL },
42 { "CONNER CTT8000-A" , NULL },
43 { "ST34342A" , NULL },
44 { NULL , NULL }
45 };
46
47 static const struct drive_list_entry drive_blacklist[] = {
48 { "WDC AC11000H" , NULL },
49 { "WDC AC22100H" , NULL },
50 { "WDC AC32500H" , NULL },
51 { "WDC AC33100H" , NULL },
52 { "WDC AC31600H" , NULL },
53 { "WDC AC32100H" , "24.09P07" },
54 { "WDC AC23200L" , "21.10N21" },
55 { "Compaq CRD-8241B" , NULL },
56 { "CRD-8400B" , NULL },
57 { "CRD-8480B", NULL },
58 { "CRD-8482B", NULL },
59 { "CRD-84" , NULL },
60 { "SanDisk SDP3B" , NULL },
61 { "SanDisk SDP3B-64" , NULL },
62 { "SANYO CD-ROM CRD" , NULL },
63 { "HITACHI CDR-8" , NULL },
64 { "HITACHI CDR-8335" , NULL },
65 { "HITACHI CDR-8435" , NULL },
66 { "Toshiba CD-ROM XM-6202B" , NULL },
67 { "TOSHIBA CD-ROM XM-1702BC", NULL },
68 { "CD-532E-A" , NULL },
69 { "E-IDE CD-ROM CR-840", NULL },
70 { "CD-ROM Drive/F5A", NULL },
71 { "WPI CDD-820", NULL },
72 { "SAMSUNG CD-ROM SC-148C", NULL },
73 { "SAMSUNG CD-ROM SC", NULL },
74 { "ATAPI CD-ROM DRIVE 40X MAXIMUM", NULL },
75 { "_NEC DV5800A", NULL },
76 { "SAMSUNG CD-ROM SN-124", "N001" },
77 { "Seagate STT20000A", NULL },
78 { "CD-ROM CDR_U200", "1.09" },
79 { NULL , NULL }
80
81 };
82
83 /**
84 * ide_dma_intr - IDE DMA interrupt handler
85 * @drive: the drive the interrupt is for
86 *
87 * Handle an interrupt completing a read/write DMA transfer on an
88 * IDE device
89 */
90
ide_dma_intr(ide_drive_t * drive)91 ide_startstop_t ide_dma_intr(ide_drive_t *drive)
92 {
93 ide_hwif_t *hwif = drive->hwif;
94 struct ide_cmd *cmd = &hwif->cmd;
95 u8 stat = 0, dma_stat = 0;
96
97 drive->waiting_for_dma = 0;
98 dma_stat = hwif->dma_ops->dma_end(drive);
99 ide_dma_unmap_sg(drive, cmd);
100 stat = hwif->tp_ops->read_status(hwif);
101
102 if (OK_STAT(stat, DRIVE_READY, drive->bad_wstat | ATA_DRQ)) {
103 if (!dma_stat) {
104 if ((cmd->tf_flags & IDE_TFLAG_FS) == 0)
105 ide_finish_cmd(drive, cmd, stat);
106 else
107 ide_complete_rq(drive, 0,
108 blk_rq_sectors(cmd->rq) << 9);
109 return ide_stopped;
110 }
111 printk(KERN_ERR "%s: %s: bad DMA status (0x%02x)\n",
112 drive->name, __func__, dma_stat);
113 }
114 return ide_error(drive, "dma_intr", stat);
115 }
116
ide_dma_good_drive(ide_drive_t * drive)117 int ide_dma_good_drive(ide_drive_t *drive)
118 {
119 return ide_in_drive_list(drive->id, drive_whitelist);
120 }
121
122 /**
123 * ide_dma_map_sg - map IDE scatter gather for DMA I/O
124 * @drive: the drive to map the DMA table for
125 * @cmd: command
126 *
127 * Perform the DMA mapping magic necessary to access the source or
128 * target buffers of a request via DMA. The lower layers of the
129 * kernel provide the necessary cache management so that we can
130 * operate in a portable fashion.
131 */
132
ide_dma_map_sg(ide_drive_t * drive,struct ide_cmd * cmd)133 static int ide_dma_map_sg(ide_drive_t *drive, struct ide_cmd *cmd)
134 {
135 ide_hwif_t *hwif = drive->hwif;
136 struct scatterlist *sg = hwif->sg_table;
137 int i;
138
139 if (cmd->tf_flags & IDE_TFLAG_WRITE)
140 cmd->sg_dma_direction = DMA_TO_DEVICE;
141 else
142 cmd->sg_dma_direction = DMA_FROM_DEVICE;
143
144 i = dma_map_sg(hwif->dev, sg, cmd->sg_nents, cmd->sg_dma_direction);
145 if (i) {
146 cmd->orig_sg_nents = cmd->sg_nents;
147 cmd->sg_nents = i;
148 }
149
150 return i;
151 }
152
153 /**
154 * ide_dma_unmap_sg - clean up DMA mapping
155 * @drive: The drive to unmap
156 *
157 * Teardown mappings after DMA has completed. This must be called
158 * after the completion of each use of ide_build_dmatable and before
159 * the next use of ide_build_dmatable. Failure to do so will cause
160 * an oops as only one mapping can be live for each target at a given
161 * time.
162 */
163
ide_dma_unmap_sg(ide_drive_t * drive,struct ide_cmd * cmd)164 void ide_dma_unmap_sg(ide_drive_t *drive, struct ide_cmd *cmd)
165 {
166 ide_hwif_t *hwif = drive->hwif;
167
168 dma_unmap_sg(hwif->dev, hwif->sg_table, cmd->orig_sg_nents,
169 cmd->sg_dma_direction);
170 }
171 EXPORT_SYMBOL_GPL(ide_dma_unmap_sg);
172
173 /**
174 * ide_dma_off_quietly - Generic DMA kill
175 * @drive: drive to control
176 *
177 * Turn off the current DMA on this IDE controller.
178 */
179
ide_dma_off_quietly(ide_drive_t * drive)180 void ide_dma_off_quietly(ide_drive_t *drive)
181 {
182 drive->dev_flags &= ~IDE_DFLAG_USING_DMA;
183 ide_toggle_bounce(drive, 0);
184
185 drive->hwif->dma_ops->dma_host_set(drive, 0);
186 }
187 EXPORT_SYMBOL(ide_dma_off_quietly);
188
189 /**
190 * ide_dma_off - disable DMA on a device
191 * @drive: drive to disable DMA on
192 *
193 * Disable IDE DMA for a device on this IDE controller.
194 * Inform the user that DMA has been disabled.
195 */
196
ide_dma_off(ide_drive_t * drive)197 void ide_dma_off(ide_drive_t *drive)
198 {
199 printk(KERN_INFO "%s: DMA disabled\n", drive->name);
200 ide_dma_off_quietly(drive);
201 }
202 EXPORT_SYMBOL(ide_dma_off);
203
204 /**
205 * ide_dma_on - Enable DMA on a device
206 * @drive: drive to enable DMA on
207 *
208 * Enable IDE DMA for a device on this IDE controller.
209 */
210
ide_dma_on(ide_drive_t * drive)211 void ide_dma_on(ide_drive_t *drive)
212 {
213 drive->dev_flags |= IDE_DFLAG_USING_DMA;
214 ide_toggle_bounce(drive, 1);
215
216 drive->hwif->dma_ops->dma_host_set(drive, 1);
217 }
218
__ide_dma_bad_drive(ide_drive_t * drive)219 int __ide_dma_bad_drive(ide_drive_t *drive)
220 {
221 u16 *id = drive->id;
222
223 int blacklist = ide_in_drive_list(id, drive_blacklist);
224 if (blacklist) {
225 printk(KERN_WARNING "%s: Disabling (U)DMA for %s (blacklisted)\n",
226 drive->name, (char *)&id[ATA_ID_PROD]);
227 return blacklist;
228 }
229 return 0;
230 }
231 EXPORT_SYMBOL(__ide_dma_bad_drive);
232
233 static const u8 xfer_mode_bases[] = {
234 XFER_UDMA_0,
235 XFER_MW_DMA_0,
236 XFER_SW_DMA_0,
237 };
238
ide_get_mode_mask(ide_drive_t * drive,u8 base,u8 req_mode)239 static unsigned int ide_get_mode_mask(ide_drive_t *drive, u8 base, u8 req_mode)
240 {
241 u16 *id = drive->id;
242 ide_hwif_t *hwif = drive->hwif;
243 const struct ide_port_ops *port_ops = hwif->port_ops;
244 unsigned int mask = 0;
245
246 switch (base) {
247 case XFER_UDMA_0:
248 if ((id[ATA_ID_FIELD_VALID] & 4) == 0)
249 break;
250 mask = id[ATA_ID_UDMA_MODES];
251 if (port_ops && port_ops->udma_filter)
252 mask &= port_ops->udma_filter(drive);
253 else
254 mask &= hwif->ultra_mask;
255
256 /*
257 * avoid false cable warning from eighty_ninty_three()
258 */
259 if (req_mode > XFER_UDMA_2) {
260 if ((mask & 0x78) && (eighty_ninty_three(drive) == 0))
261 mask &= 0x07;
262 }
263 break;
264 case XFER_MW_DMA_0:
265 mask = id[ATA_ID_MWDMA_MODES];
266
267 /* Also look for the CF specific MWDMA modes... */
268 if (ata_id_is_cfa(id) && (id[ATA_ID_CFA_MODES] & 0x38)) {
269 u8 mode = ((id[ATA_ID_CFA_MODES] & 0x38) >> 3) - 1;
270
271 mask |= ((2 << mode) - 1) << 3;
272 }
273
274 if (port_ops && port_ops->mdma_filter)
275 mask &= port_ops->mdma_filter(drive);
276 else
277 mask &= hwif->mwdma_mask;
278 break;
279 case XFER_SW_DMA_0:
280 mask = id[ATA_ID_SWDMA_MODES];
281 if (!(mask & ATA_SWDMA2) && (id[ATA_ID_OLD_DMA_MODES] >> 8)) {
282 u8 mode = id[ATA_ID_OLD_DMA_MODES] >> 8;
283
284 /*
285 * if the mode is valid convert it to the mask
286 * (the maximum allowed mode is XFER_SW_DMA_2)
287 */
288 if (mode <= 2)
289 mask = (2 << mode) - 1;
290 }
291 mask &= hwif->swdma_mask;
292 break;
293 default:
294 BUG();
295 break;
296 }
297
298 return mask;
299 }
300
301 /**
302 * ide_find_dma_mode - compute DMA speed
303 * @drive: IDE device
304 * @req_mode: requested mode
305 *
306 * Checks the drive/host capabilities and finds the speed to use for
307 * the DMA transfer. The speed is then limited by the requested mode.
308 *
309 * Returns 0 if the drive/host combination is incapable of DMA transfers
310 * or if the requested mode is not a DMA mode.
311 */
312
ide_find_dma_mode(ide_drive_t * drive,u8 req_mode)313 u8 ide_find_dma_mode(ide_drive_t *drive, u8 req_mode)
314 {
315 ide_hwif_t *hwif = drive->hwif;
316 unsigned int mask;
317 int x, i;
318 u8 mode = 0;
319
320 if (drive->media != ide_disk) {
321 if (hwif->host_flags & IDE_HFLAG_NO_ATAPI_DMA)
322 return 0;
323 }
324
325 for (i = 0; i < ARRAY_SIZE(xfer_mode_bases); i++) {
326 if (req_mode < xfer_mode_bases[i])
327 continue;
328 mask = ide_get_mode_mask(drive, xfer_mode_bases[i], req_mode);
329 x = fls(mask) - 1;
330 if (x >= 0) {
331 mode = xfer_mode_bases[i] + x;
332 break;
333 }
334 }
335
336 if (hwif->chipset == ide_acorn && mode == 0) {
337 /*
338 * is this correct?
339 */
340 if (ide_dma_good_drive(drive) &&
341 drive->id[ATA_ID_EIDE_DMA_TIME] < 150)
342 mode = XFER_MW_DMA_1;
343 }
344
345 mode = min(mode, req_mode);
346
347 printk(KERN_INFO "%s: %s mode selected\n", drive->name,
348 mode ? ide_xfer_verbose(mode) : "no DMA");
349
350 return mode;
351 }
352
ide_tune_dma(ide_drive_t * drive)353 static int ide_tune_dma(ide_drive_t *drive)
354 {
355 ide_hwif_t *hwif = drive->hwif;
356 u8 speed;
357
358 if (ata_id_has_dma(drive->id) == 0 ||
359 (drive->dev_flags & IDE_DFLAG_NODMA))
360 return 0;
361
362 /* consult the list of known "bad" drives */
363 if (__ide_dma_bad_drive(drive))
364 return 0;
365
366 if (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA)
367 return config_drive_for_dma(drive);
368
369 speed = ide_max_dma_mode(drive);
370
371 if (!speed)
372 return 0;
373
374 if (ide_set_dma_mode(drive, speed))
375 return 0;
376
377 return 1;
378 }
379
ide_dma_check(ide_drive_t * drive)380 static int ide_dma_check(ide_drive_t *drive)
381 {
382 ide_hwif_t *hwif = drive->hwif;
383
384 if (ide_tune_dma(drive))
385 return 0;
386
387 /* TODO: always do PIO fallback */
388 if (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA)
389 return -1;
390
391 ide_set_max_pio(drive);
392
393 return -1;
394 }
395
ide_set_dma(ide_drive_t * drive)396 int ide_set_dma(ide_drive_t *drive)
397 {
398 int rc;
399
400 /*
401 * Force DMAing for the beginning of the check.
402 * Some chipsets appear to do interesting
403 * things, if not checked and cleared.
404 * PARANOIA!!!
405 */
406 ide_dma_off_quietly(drive);
407
408 rc = ide_dma_check(drive);
409 if (rc)
410 return rc;
411
412 ide_dma_on(drive);
413
414 return 0;
415 }
416
ide_check_dma_crc(ide_drive_t * drive)417 void ide_check_dma_crc(ide_drive_t *drive)
418 {
419 u8 mode;
420
421 ide_dma_off_quietly(drive);
422 drive->crc_count = 0;
423 mode = drive->current_speed;
424 /*
425 * Don't try non Ultra-DMA modes without iCRC's. Force the
426 * device to PIO and make the user enable SWDMA/MWDMA modes.
427 */
428 if (mode > XFER_UDMA_0 && mode <= XFER_UDMA_7)
429 mode--;
430 else
431 mode = XFER_PIO_4;
432 ide_set_xfer_rate(drive, mode);
433 if (drive->current_speed >= XFER_SW_DMA_0)
434 ide_dma_on(drive);
435 }
436
ide_dma_lost_irq(ide_drive_t * drive)437 void ide_dma_lost_irq(ide_drive_t *drive)
438 {
439 printk(KERN_ERR "%s: DMA interrupt recovery\n", drive->name);
440 }
441 EXPORT_SYMBOL_GPL(ide_dma_lost_irq);
442
443 /*
444 * un-busy the port etc, and clear any pending DMA status. we want to
445 * retry the current request in pio mode instead of risking tossing it
446 * all away
447 */
ide_dma_timeout_retry(ide_drive_t * drive,int error)448 ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
449 {
450 ide_hwif_t *hwif = drive->hwif;
451 const struct ide_dma_ops *dma_ops = hwif->dma_ops;
452 struct ide_cmd *cmd = &hwif->cmd;
453 ide_startstop_t ret = ide_stopped;
454
455 /*
456 * end current dma transaction
457 */
458
459 if (error < 0) {
460 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name);
461 drive->waiting_for_dma = 0;
462 (void)dma_ops->dma_end(drive);
463 ide_dma_unmap_sg(drive, cmd);
464 ret = ide_error(drive, "dma timeout error",
465 hwif->tp_ops->read_status(hwif));
466 } else {
467 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name);
468 if (dma_ops->dma_clear)
469 dma_ops->dma_clear(drive);
470 printk(KERN_ERR "%s: timeout waiting for DMA\n", drive->name);
471 if (dma_ops->dma_test_irq(drive) == 0) {
472 ide_dump_status(drive, "DMA timeout",
473 hwif->tp_ops->read_status(hwif));
474 drive->waiting_for_dma = 0;
475 (void)dma_ops->dma_end(drive);
476 ide_dma_unmap_sg(drive, cmd);
477 }
478 }
479
480 /*
481 * disable dma for now, but remember that we did so because of
482 * a timeout -- we'll reenable after we finish this next request
483 * (or rather the first chunk of it) in pio.
484 */
485 drive->dev_flags |= IDE_DFLAG_DMA_PIO_RETRY;
486 drive->retry_pio++;
487 ide_dma_off_quietly(drive);
488
489 /*
490 * make sure request is sane
491 */
492 if (hwif->rq)
493 hwif->rq->errors = 0;
494 return ret;
495 }
496
ide_release_dma_engine(ide_hwif_t * hwif)497 void ide_release_dma_engine(ide_hwif_t *hwif)
498 {
499 if (hwif->dmatable_cpu) {
500 int prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
501
502 dma_free_coherent(hwif->dev, prd_size,
503 hwif->dmatable_cpu, hwif->dmatable_dma);
504 hwif->dmatable_cpu = NULL;
505 }
506 }
507 EXPORT_SYMBOL_GPL(ide_release_dma_engine);
508
ide_allocate_dma_engine(ide_hwif_t * hwif)509 int ide_allocate_dma_engine(ide_hwif_t *hwif)
510 {
511 int prd_size;
512
513 if (hwif->prd_max_nents == 0)
514 hwif->prd_max_nents = PRD_ENTRIES;
515 if (hwif->prd_ent_size == 0)
516 hwif->prd_ent_size = PRD_BYTES;
517
518 prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
519
520 hwif->dmatable_cpu = dma_alloc_coherent(hwif->dev, prd_size,
521 &hwif->dmatable_dma,
522 GFP_ATOMIC);
523 if (hwif->dmatable_cpu == NULL) {
524 printk(KERN_ERR "%s: unable to allocate PRD table\n",
525 hwif->name);
526 return -ENOMEM;
527 }
528
529 return 0;
530 }
531 EXPORT_SYMBOL_GPL(ide_allocate_dma_engine);
532
ide_dma_prepare(ide_drive_t * drive,struct ide_cmd * cmd)533 int ide_dma_prepare(ide_drive_t *drive, struct ide_cmd *cmd)
534 {
535 const struct ide_dma_ops *dma_ops = drive->hwif->dma_ops;
536
537 if ((drive->dev_flags & IDE_DFLAG_USING_DMA) == 0 ||
538 (dma_ops->dma_check && dma_ops->dma_check(drive, cmd)))
539 goto out;
540 ide_map_sg(drive, cmd);
541 if (ide_dma_map_sg(drive, cmd) == 0)
542 goto out_map;
543 if (dma_ops->dma_setup(drive, cmd))
544 goto out_dma_unmap;
545 drive->waiting_for_dma = 1;
546 return 0;
547 out_dma_unmap:
548 ide_dma_unmap_sg(drive, cmd);
549 out_map:
550 ide_map_sg(drive, cmd);
551 out:
552 return 1;
553 }
554