drivers/ide/ide-dma.c

   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/kernel.h>
  33 #include <linux/ide.h>
  34 #include <linux/scatterlist.h>
  35 #include <linux/dma-mapping.h>
  36
  37 static const struct drive_list_entry drive_whitelist[] = {
  38         { "Micropolis 2112A"    ,       NULL            },
  39         { "CONNER CTMA 4000"    ,       NULL            },
  40         { "CONNER CTT8000-A"    ,       NULL            },
  41         { "ST34342A"            ,       NULL            },
  42         { NULL                  ,       NULL            }
  43 };
  44
  45 static const struct drive_list_entry drive_blacklist[] = {
  46         { "WDC AC11000H"        ,       NULL            },
  47         { "WDC AC22100H"        ,       NULL            },
  48         { "WDC AC32500H"        ,       NULL            },
  49         { "WDC AC33100H"        ,       NULL            },
  50         { "WDC AC31600H"        ,       NULL            },
  51         { "WDC AC32100H"        ,       "24.09P07"      },
  52         { "WDC AC23200L"        ,       "21.10N21"      },
  53         { "Compaq CRD-8241B"    ,       NULL            },
  54         { "CRD-8400B"           ,       NULL            },
  55         { "CRD-8480B",                  NULL            },
  56         { "CRD-8482B",                  NULL            },
  57         { "CRD-84"              ,       NULL            },
  58         { "SanDisk SDP3B"       ,       NULL            },
  59         { "SanDisk SDP3B-64"    ,       NULL            },
  60         { "SANYO CD-ROM CRD"    ,       NULL            },
  61         { "HITACHI CDR-8"       ,       NULL            },
  62         { "HITACHI CDR-8335"    ,       NULL            },
  63         { "HITACHI CDR-8435"    ,       NULL            },
  64         { "Toshiba CD-ROM XM-6202B"     ,       NULL            },
  65         { "TOSHIBA CD-ROM XM-1702BC",   NULL            },
  66         { "CD-532E-A"           ,       NULL            },
  67         { "E-IDE CD-ROM CR-840",        NULL            },
  68         { "CD-ROM Drive/F5A",   NULL            },
  69         { "WPI CDD-820",                NULL            },
  70         { "SAMSUNG CD-ROM SC-148C",     NULL            },
  71         { "SAMSUNG CD-ROM SC",  NULL            },
  72         { "ATAPI CD-ROM DRIVE 40X MAXIMUM",     NULL            },
  73         { "_NEC DV5800A",               NULL            },
  74         { "SAMSUNG CD-ROM SN-124",      "N001" },
  75         { "Seagate STT20000A",          NULL  },
  76         { "CD-ROM CDR_U200",            "1.09" },
  77         { NULL                  ,       NULL            }
  78
  79 };
  80
  81 /**
  82  *      ide_dma_intr    -       IDE DMA interrupt handler
  83  *      @drive: the drive the interrupt is for
  84  *
  85  *      Handle an interrupt completing a read/write DMA transfer on an
  86  *      IDE device
  87  */
  88
  89 ide_startstop_t ide_dma_intr(ide_drive_t *drive)
  90 {
  91         ide_hwif_t *hwif = drive->hwif;
  92         u8 stat = 0, dma_stat = 0;
  93
  94         dma_stat = hwif->dma_ops->dma_end(drive);
  95         stat = hwif->tp_ops->read_status(hwif);
  96
  97         if (OK_STAT(stat, DRIVE_READY, drive->bad_wstat | ATA_DRQ)) {
  98                 if (!dma_stat) {
  99                         struct ide_cmd *cmd = &hwif->cmd;
 100
 101                         ide_finish_cmd(drive, cmd, stat);
 102                         return ide_stopped;
 103                 }
 104                 printk(KERN_ERR "%s: %s: bad DMA status (0x%02x)\n",
 105                         drive->name, __func__, dma_stat);
 106         }
 107         return ide_error(drive, "dma_intr", stat);
 108 }
 109 EXPORT_SYMBOL_GPL(ide_dma_intr);
 110
 111 int ide_dma_good_drive(ide_drive_t *drive)
 112 {
 113         return ide_in_drive_list(drive->id, drive_whitelist);
 114 }
 115
 116 /**
 117  *      ide_build_sglist        -       map IDE scatter gather for DMA I/O
 118  *      @drive: the drive to build the DMA table for
 119  *      @rq: the request holding the sg list
 120  *
 121  *      Perform the DMA mapping magic necessary to access the source or
 122  *      target buffers of a request via DMA.  The lower layers of the
 123  *      kernel provide the necessary cache management so that we can
 124  *      operate in a portable fashion.
 125  */
 126
 127 int ide_build_sglist(ide_drive_t *drive, struct request *rq)
 128 {
 129         ide_hwif_t *hwif = drive->hwif;
 130         struct scatterlist *sg = hwif->sg_table;
 131         int i;
 132
 133         ide_map_sg(drive, rq);
 134
 135         if (rq_data_dir(rq) == READ)
 136                 hwif->sg_dma_direction = DMA_FROM_DEVICE;
 137         else
 138                 hwif->sg_dma_direction = DMA_TO_DEVICE;
 139
 140         i = dma_map_sg(hwif->dev, sg, hwif->sg_nents, hwif->sg_dma_direction);
 141         if (i == 0)
 142                 ide_map_sg(drive, rq);
 143         else {
 144                 hwif->orig_sg_nents = hwif->sg_nents;
 145                 hwif->sg_nents = i;
 146         }
 147
 148         return i;
 149 }
 150
 151 /**
 152  *      ide_destroy_dmatable    -       clean up DMA mapping
 153  *      @drive: The drive to unmap
 154  *
 155  *      Teardown mappings after DMA has completed. This must be called
 156  *      after the completion of each use of ide_build_dmatable and before
 157  *      the next use of ide_build_dmatable. Failure to do so will cause
 158  *      an oops as only one mapping can be live for each target at a given
 159  *      time.
 160  */
 161
 162 void ide_destroy_dmatable(ide_drive_t *drive)
 163 {
 164         ide_hwif_t *hwif = drive->hwif;
 165
 166         dma_unmap_sg(hwif->dev, hwif->sg_table, hwif->orig_sg_nents,
 167                      hwif->sg_dma_direction);
 168 }
 169 EXPORT_SYMBOL_GPL(ide_destroy_dmatable);
 170
 171 /**
 172  *      ide_dma_off_quietly     -       Generic DMA kill
 173  *      @drive: drive to control
 174  *
 175  *      Turn off the current DMA on this IDE controller.
 176  */
 177
 178 void ide_dma_off_quietly(ide_drive_t *drive)
 179 {
 180         drive->dev_flags &= ~IDE_DFLAG_USING_DMA;
 181         ide_toggle_bounce(drive, 0);
 182
 183         drive->hwif->dma_ops->dma_host_set(drive, 0);
 184 }
 185 EXPORT_SYMBOL(ide_dma_off_quietly);
 186
 187 /**
 188  *      ide_dma_off     -       disable DMA on a device
 189  *      @drive: drive to disable DMA on
 190  *
 191  *      Disable IDE DMA for a device on this IDE controller.
 192  *      Inform the user that DMA has been disabled.
 193  */
 194
 195 void ide_dma_off(ide_drive_t *drive)
 196 {
 197         printk(KERN_INFO "%s: DMA disabled\n", drive->name);
 198         ide_dma_off_quietly(drive);
 199 }
 200 EXPORT_SYMBOL(ide_dma_off);
 201
 202 /**
 203  *      ide_dma_on              -       Enable DMA on a device
 204  *      @drive: drive to enable DMA on
 205  *
 206  *      Enable IDE DMA for a device on this IDE controller.
 207  */
 208
 209 void ide_dma_on(ide_drive_t *drive)
 210 {
 211         drive->dev_flags |= IDE_DFLAG_USING_DMA;
 212         ide_toggle_bounce(drive, 1);
 213
 214         drive->hwif->dma_ops->dma_host_set(drive, 1);
 215 }
 216
 217 int __ide_dma_bad_drive(ide_drive_t *drive)
 218 {
 219         u16 *id = drive->id;
 220
 221         int blacklist = ide_in_drive_list(id, drive_blacklist);
 222         if (blacklist) {
 223                 printk(KERN_WARNING "%s: Disabling (U)DMA for %s (blacklisted)\n",
 224                                     drive->name, (char *)&id[ATA_ID_PROD]);
 225                 return blacklist;
 226         }
 227         return 0;
 228 }
 229 EXPORT_SYMBOL(__ide_dma_bad_drive);
 230
 231 static const u8 xfer_mode_bases[] = {
 232         XFER_UDMA_0,
 233         XFER_MW_DMA_0,
 234         XFER_SW_DMA_0,
 235 };
 236
 237 static unsigned int ide_get_mode_mask(ide_drive_t *drive, u8 base, u8 req_mode)
 238 {
 239         u16 *id = drive->id;
 240         ide_hwif_t *hwif = drive->hwif;
 241         const struct ide_port_ops *port_ops = hwif->port_ops;
 242         unsigned int mask = 0;
 243
 244         switch (base) {
 245         case XFER_UDMA_0:
 246                 if ((id[ATA_ID_FIELD_VALID] & 4) == 0)
 247                         break;
 248
 249                 if (port_ops && port_ops->udma_filter)
 250                         mask = port_ops->udma_filter(drive);
 251                 else
 252                         mask = hwif->ultra_mask;
 253                 mask &= id[ATA_ID_UDMA_MODES];
 254
 255                 /*
 256                  * avoid false cable warning from eighty_ninty_three()
 257                  */
 258                 if (req_mode > XFER_UDMA_2) {
 259                         if ((mask & 0x78) && (eighty_ninty_three(drive) == 0))
 260                                 mask &= 0x07;
 261                 }
 262                 break;
 263         case XFER_MW_DMA_0:
 264                 if ((id[ATA_ID_FIELD_VALID] & 2) == 0)
 265                         break;
 266                 if (port_ops && port_ops->mdma_filter)
 267                         mask = port_ops->mdma_filter(drive);
 268                 else
 269                         mask = hwif->mwdma_mask;
 270                 mask &= id[ATA_ID_MWDMA_MODES];
 271                 break;
 272         case XFER_SW_DMA_0:
 273                 if (id[ATA_ID_FIELD_VALID] & 2) {
 274                         mask = id[ATA_ID_SWDMA_MODES] & hwif->swdma_mask;
 275                 } else if (id[ATA_ID_OLD_DMA_MODES] >> 8) {
 276                         u8 mode = id[ATA_ID_OLD_DMA_MODES] >> 8;
 277
 278                         /*
 279                          * if the mode is valid convert it to the mask
 280                          * (the maximum allowed mode is XFER_SW_DMA_2)
 281                          */
 282                         if (mode <= 2)
 283                                 mask = ((2 << mode) - 1) & hwif->swdma_mask;
 284                 }
 285                 break;
 286         default:
 287                 BUG();
 288                 break;
 289         }
 290
 291         return mask;
 292 }
 293
 294 /**
 295  *      ide_find_dma_mode       -       compute DMA speed
 296  *      @drive: IDE device
 297  *      @req_mode: requested mode
 298  *
 299  *      Checks the drive/host capabilities and finds the speed to use for
 300  *      the DMA transfer.  The speed is then limited by the requested mode.
 301  *
 302  *      Returns 0 if the drive/host combination is incapable of DMA transfers
 303  *      or if the requested mode is not a DMA mode.
 304  */
 305
 306 u8 ide_find_dma_mode(ide_drive_t *drive, u8 req_mode)
 307 {
 308         ide_hwif_t *hwif = drive->hwif;
 309         unsigned int mask;
 310         int x, i;
 311         u8 mode = 0;
 312
 313         if (drive->media != ide_disk) {
 314                 if (hwif->host_flags & IDE_HFLAG_NO_ATAPI_DMA)
 315                         return 0;
 316         }
 317
 318         for (i = 0; i < ARRAY_SIZE(xfer_mode_bases); i++) {
 319                 if (req_mode < xfer_mode_bases[i])
 320                         continue;
 321                 mask = ide_get_mode_mask(drive, xfer_mode_bases[i], req_mode);
 322                 x = fls(mask) - 1;
 323                 if (x >= 0) {
 324                         mode = xfer_mode_bases[i] + x;
 325                         break;
 326                 }
 327         }
 328
 329         if (hwif->chipset == ide_acorn && mode == 0) {
 330                 /*
 331                  * is this correct?
 332                  */
 333                 if (ide_dma_good_drive(drive) &&
 334                     drive->id[ATA_ID_EIDE_DMA_TIME] < 150)
 335                         mode = XFER_MW_DMA_1;
 336         }
 337
 338         mode = min(mode, req_mode);
 339
 340         printk(KERN_INFO "%s: %s mode selected\n", drive->name,
 341                           mode ? ide_xfer_verbose(mode) : "no DMA");
 342
 343         return mode;
 344 }
 345 EXPORT_SYMBOL_GPL(ide_find_dma_mode);
 346
 347 static int ide_tune_dma(ide_drive_t *drive)
 348 {
 349         ide_hwif_t *hwif = drive->hwif;
 350         u8 speed;
 351
 352         if (ata_id_has_dma(drive->id) == 0 ||
 353             (drive->dev_flags & IDE_DFLAG_NODMA))
 354                 return 0;
 355
 356         /* consult the list of known "bad" drives */
 357         if (__ide_dma_bad_drive(drive))
 358                 return 0;
 359
 360         if (ide_id_dma_bug(drive))
 361                 return 0;
 362
 363         if (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA)
 364                 return config_drive_for_dma(drive);
 365
 366         speed = ide_max_dma_mode(drive);
 367
 368         if (!speed)
 369                 return 0;
 370
 371         if (ide_set_dma_mode(drive, speed))
 372                 return 0;
 373
 374         return 1;
 375 }
 376
 377 static int ide_dma_check(ide_drive_t *drive)
 378 {
 379         ide_hwif_t *hwif = drive->hwif;
 380
 381         if (ide_tune_dma(drive))
 382                 return 0;
 383
 384         /* TODO: always do PIO fallback */
 385         if (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA)
 386                 return -1;
 387
 388         ide_set_max_pio(drive);
 389
 390         return -1;
 391 }
 392
 393 int ide_id_dma_bug(ide_drive_t *drive)
 394 {
 395         u16 *id = drive->id;
 396
 397         if (id[ATA_ID_FIELD_VALID] & 4) {
 398                 if ((id[ATA_ID_UDMA_MODES] >> 8) &&
 399                     (id[ATA_ID_MWDMA_MODES] >> 8))
 400                         goto err_out;
 401         } else if (id[ATA_ID_FIELD_VALID] & 2) {
 402                 if ((id[ATA_ID_MWDMA_MODES] >> 8) &&
 403                     (id[ATA_ID_SWDMA_MODES] >> 8))
 404                         goto err_out;
 405         }
 406         return 0;
 407 err_out:
 408         printk(KERN_ERR "%s: bad DMA info in identify block\n", drive->name);
 409         return 1;
 410 }
 411
 412 int ide_set_dma(ide_drive_t *drive)
 413 {
 414         int rc;
 415
 416         /*
 417          * Force DMAing for the beginning of the check.
 418          * Some chipsets appear to do interesting
 419          * things, if not checked and cleared.
 420          *   PARANOIA!!!
 421          */
 422         ide_dma_off_quietly(drive);
 423
 424         rc = ide_dma_check(drive);
 425         if (rc)
 426                 return rc;
 427
 428         ide_dma_on(drive);
 429
 430         return 0;
 431 }
 432
 433 void ide_check_dma_crc(ide_drive_t *drive)
 434 {
 435         u8 mode;
 436
 437         ide_dma_off_quietly(drive);
 438         drive->crc_count = 0;
 439         mode = drive->current_speed;
 440         /*
 441          * Don't try non Ultra-DMA modes without iCRC's.  Force the
 442          * device to PIO and make the user enable SWDMA/MWDMA modes.
 443          */
 444         if (mode > XFER_UDMA_0 && mode <= XFER_UDMA_7)
 445                 mode--;
 446         else
 447                 mode = XFER_PIO_4;
 448         ide_set_xfer_rate(drive, mode);
 449         if (drive->current_speed >= XFER_SW_DMA_0)
 450                 ide_dma_on(drive);
 451 }
 452
 453 void ide_dma_lost_irq(ide_drive_t *drive)
 454 {
 455         printk(KERN_ERR "%s: DMA interrupt recovery\n", drive->name);
 456 }
 457 EXPORT_SYMBOL_GPL(ide_dma_lost_irq);
 458
 459 void ide_dma_timeout(ide_drive_t *drive)
 460 {
 461         ide_hwif_t *hwif = drive->hwif;
 462
 463         printk(KERN_ERR "%s: timeout waiting for DMA\n", drive->name);
 464
 465         if (hwif->dma_ops->dma_test_irq(drive))
 466                 return;
 467
 468         ide_dump_status(drive, "DMA timeout", hwif->tp_ops->read_status(hwif));
 469
 470         hwif->dma_ops->dma_end(drive);
 471 }
 472 EXPORT_SYMBOL_GPL(ide_dma_timeout);
 473
 474 /*
 475  * un-busy the port etc, and clear any pending DMA status. we want to
 476  * retry the current request in pio mode instead of risking tossing it
 477  * all away
 478  */
 479 ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
 480 {
 481         ide_hwif_t *hwif = drive->hwif;
 482         struct request *rq;
 483         ide_startstop_t ret = ide_stopped;
 484
 485         /*
 486          * end current dma transaction
 487          */
 488
 489         if (error < 0) {
 490                 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name);
 491                 (void)hwif->dma_ops->dma_end(drive);
 492                 ret = ide_error(drive, "dma timeout error",
 493                                 hwif->tp_ops->read_status(hwif));
 494         } else {
 495                 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name);
 496                 hwif->dma_ops->dma_timeout(drive);
 497         }
 498
 499         /*
 500          * disable dma for now, but remember that we did so because of
 501          * a timeout -- we'll reenable after we finish this next request
 502          * (or rather the first chunk of it) in pio.
 503          */
 504         drive->dev_flags |= IDE_DFLAG_DMA_PIO_RETRY;
 505         drive->retry_pio++;
 506         ide_dma_off_quietly(drive);
 507
 508         /*
 509          * un-busy drive etc and make sure request is sane
 510          */
 511
 512         rq = hwif->rq;
 513         if (!rq)
 514                 goto out;
 515
 516         hwif->rq = NULL;
 517
 518         rq->errors = 0;
 519
 520         if (!rq->bio)
 521                 goto out;
 522
 523         rq->sector = rq->bio->bi_sector;
 524         rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9;
 525         rq->hard_cur_sectors = rq->current_nr_sectors;
 526         rq->buffer = bio_data(rq->bio);
 527 out:
 528         return ret;
 529 }
 530
 531 void ide_release_dma_engine(ide_hwif_t *hwif)
 532 {
 533         if (hwif->dmatable_cpu) {
 534                 int prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
 535
 536                 dma_free_coherent(hwif->dev, prd_size,
 537                                   hwif->dmatable_cpu, hwif->dmatable_dma);
 538                 hwif->dmatable_cpu = NULL;
 539         }
 540 }
 541 EXPORT_SYMBOL_GPL(ide_release_dma_engine);
 542
 543 int ide_allocate_dma_engine(ide_hwif_t *hwif)
 544 {
 545         int prd_size;
 546
 547         if (hwif->prd_max_nents == 0)
 548                 hwif->prd_max_nents = PRD_ENTRIES;
 549         if (hwif->prd_ent_size == 0)
 550                 hwif->prd_ent_size = PRD_BYTES;
 551
 552         prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
 553
 554         hwif->dmatable_cpu = dma_alloc_coherent(hwif->dev, prd_size,
 555                                                 &hwif->dmatable_dma,
 556                                                 GFP_ATOMIC);
 557         if (hwif->dmatable_cpu == NULL) {
 558                 printk(KERN_ERR "%s: unable to allocate PRD table\n",
 559                         hwif->name);
 560                 return -ENOMEM;
 561         }
 562
 563         return 0;
 564 }
 565 EXPORT_SYMBOL_GPL(ide_allocate_dma_engine);