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         drive->waiting_for_dma = 0;
  95         dma_stat = hwif->dma_ops->dma_end(drive);
  96         ide_destroy_dmatable(drive);
  97         stat = hwif->tp_ops->read_status(hwif);
  98
  99         if (OK_STAT(stat, DRIVE_READY, drive->bad_wstat | ATA_DRQ)) {
 100                 if (!dma_stat) {
 101                         struct ide_cmd *cmd = &hwif->cmd;
 102
 103                         if ((cmd->tf_flags & IDE_TFLAG_FS) == 0)
 104                                 ide_finish_cmd(drive, cmd, stat);
 105                         else
 106                                 ide_complete_rq(drive, 0,
 107                                                 cmd->rq->nr_sectors << 9);
 108                         return ide_stopped;
 109                 }
 110                 printk(KERN_ERR "%s: %s: bad DMA status (0x%02x)\n",
 111                         drive->name, __func__, dma_stat);
 112         }
 113         return ide_error(drive, "dma_intr", stat);
 114 }
 115
 116 int ide_dma_good_drive(ide_drive_t *drive)
 117 {
 118         return ide_in_drive_list(drive->id, drive_whitelist);
 119 }
 120
 121 /**
 122  *      ide_build_sglist        -       map IDE scatter gather for DMA I/O
 123  *      @drive: the drive to build the DMA table for
 124  *      @cmd: command
 125  *
 126  *      Perform the DMA mapping magic necessary to access the source or
 127  *      target buffers of a request via DMA.  The lower layers of the
 128  *      kernel provide the necessary cache management so that we can
 129  *      operate in a portable fashion.
 130  */
 131
 132 static int ide_build_sglist(ide_drive_t *drive, struct ide_cmd *cmd)
 133 {
 134         ide_hwif_t *hwif = drive->hwif;
 135         struct scatterlist *sg = hwif->sg_table;
 136         int i;
 137
 138         ide_map_sg(drive, cmd);
 139
 140         if (cmd->tf_flags & IDE_TFLAG_WRITE)
 141                 cmd->sg_dma_direction = DMA_TO_DEVICE;
 142         else
 143                 cmd->sg_dma_direction = DMA_FROM_DEVICE;
 144
 145         i = dma_map_sg(hwif->dev, sg, cmd->sg_nents, cmd->sg_dma_direction);
 146         if (i == 0)
 147                 ide_map_sg(drive, cmd);
 148         else {
 149                 cmd->orig_sg_nents = cmd->sg_nents;
 150                 cmd->sg_nents = i;
 151         }
 152
 153         return i;
 154 }
 155
 156 /**
 157  *      ide_destroy_dmatable    -       clean up DMA mapping
 158  *      @drive: The drive to unmap
 159  *
 160  *      Teardown mappings after DMA has completed. This must be called
 161  *      after the completion of each use of ide_build_dmatable and before
 162  *      the next use of ide_build_dmatable. Failure to do so will cause
 163  *      an oops as only one mapping can be live for each target at a given
 164  *      time.
 165  */
 166
 167 void ide_destroy_dmatable(ide_drive_t *drive)
 168 {
 169         ide_hwif_t *hwif = drive->hwif;
 170         struct ide_cmd *cmd = &hwif->cmd;
 171
 172         dma_unmap_sg(hwif->dev, hwif->sg_table, cmd->orig_sg_nents,
 173                      cmd->sg_dma_direction);
 174 }
 175 EXPORT_SYMBOL_GPL(ide_destroy_dmatable);
 176
 177 /**
 178  *      ide_dma_off_quietly     -       Generic DMA kill
 179  *      @drive: drive to control
 180  *
 181  *      Turn off the current DMA on this IDE controller.
 182  */
 183
 184 void ide_dma_off_quietly(ide_drive_t *drive)
 185 {
 186         drive->dev_flags &= ~IDE_DFLAG_USING_DMA;
 187         ide_toggle_bounce(drive, 0);
 188
 189         drive->hwif->dma_ops->dma_host_set(drive, 0);
 190 }
 191 EXPORT_SYMBOL(ide_dma_off_quietly);
 192
 193 /**
 194  *      ide_dma_off     -       disable DMA on a device
 195  *      @drive: drive to disable DMA on
 196  *
 197  *      Disable IDE DMA for a device on this IDE controller.
 198  *      Inform the user that DMA has been disabled.
 199  */
 200
 201 void ide_dma_off(ide_drive_t *drive)
 202 {
 203         printk(KERN_INFO "%s: DMA disabled\n", drive->name);
 204         ide_dma_off_quietly(drive);
 205 }
 206 EXPORT_SYMBOL(ide_dma_off);
 207
 208 /**
 209  *      ide_dma_on              -       Enable DMA on a device
 210  *      @drive: drive to enable DMA on
 211  *
 212  *      Enable IDE DMA for a device on this IDE controller.
 213  */
 214
 215 void ide_dma_on(ide_drive_t *drive)
 216 {
 217         drive->dev_flags |= IDE_DFLAG_USING_DMA;
 218         ide_toggle_bounce(drive, 1);
 219
 220         drive->hwif->dma_ops->dma_host_set(drive, 1);
 221 }
 222
 223 int __ide_dma_bad_drive(ide_drive_t *drive)
 224 {
 225         u16 *id = drive->id;
 226
 227         int blacklist = ide_in_drive_list(id, drive_blacklist);
 228         if (blacklist) {
 229                 printk(KERN_WARNING "%s: Disabling (U)DMA for %s (blacklisted)\n",
 230                                     drive->name, (char *)&id[ATA_ID_PROD]);
 231                 return blacklist;
 232         }
 233         return 0;
 234 }
 235 EXPORT_SYMBOL(__ide_dma_bad_drive);
 236
 237 static const u8 xfer_mode_bases[] = {
 238         XFER_UDMA_0,
 239         XFER_MW_DMA_0,
 240         XFER_SW_DMA_0,
 241 };
 242
 243 static unsigned int ide_get_mode_mask(ide_drive_t *drive, u8 base, u8 req_mode)
 244 {
 245         u16 *id = drive->id;
 246         ide_hwif_t *hwif = drive->hwif;
 247         const struct ide_port_ops *port_ops = hwif->port_ops;
 248         unsigned int mask = 0;
 249
 250         switch (base) {
 251         case XFER_UDMA_0:
 252                 if ((id[ATA_ID_FIELD_VALID] & 4) == 0)
 253                         break;
 254
 255                 if (port_ops && port_ops->udma_filter)
 256                         mask = port_ops->udma_filter(drive);
 257                 else
 258                         mask = hwif->ultra_mask;
 259                 mask &= id[ATA_ID_UDMA_MODES];
 260
 261                 /*
 262                  * avoid false cable warning from eighty_ninty_three()
 263                  */
 264                 if (req_mode > XFER_UDMA_2) {
 265                         if ((mask & 0x78) && (eighty_ninty_three(drive) == 0))
 266                                 mask &= 0x07;
 267                 }
 268                 break;
 269         case XFER_MW_DMA_0:
 270                 if ((id[ATA_ID_FIELD_VALID] & 2) == 0)
 271                         break;
 272                 if (port_ops && port_ops->mdma_filter)
 273                         mask = port_ops->mdma_filter(drive);
 274                 else
 275                         mask = hwif->mwdma_mask;
 276                 mask &= id[ATA_ID_MWDMA_MODES];
 277                 break;
 278         case XFER_SW_DMA_0:
 279                 if (id[ATA_ID_FIELD_VALID] & 2) {
 280                         mask = id[ATA_ID_SWDMA_MODES] & hwif->swdma_mask;
 281                 } else if (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) & hwif->swdma_mask;
 290                 }
 291                 break;
 292         default:
 293                 BUG();
 294                 break;
 295         }
 296
 297         return mask;
 298 }
 299
 300 /**
 301  *      ide_find_dma_mode       -       compute DMA speed
 302  *      @drive: IDE device
 303  *      @req_mode: requested mode
 304  *
 305  *      Checks the drive/host capabilities and finds the speed to use for
 306  *      the DMA transfer.  The speed is then limited by the requested mode.
 307  *
 308  *      Returns 0 if the drive/host combination is incapable of DMA transfers
 309  *      or if the requested mode is not a DMA mode.
 310  */
 311
 312 u8 ide_find_dma_mode(ide_drive_t *drive, u8 req_mode)
 313 {
 314         ide_hwif_t *hwif = drive->hwif;
 315         unsigned int mask;
 316         int x, i;
 317         u8 mode = 0;
 318
 319         if (drive->media != ide_disk) {
 320                 if (hwif->host_flags & IDE_HFLAG_NO_ATAPI_DMA)
 321                         return 0;
 322         }
 323
 324         for (i = 0; i < ARRAY_SIZE(xfer_mode_bases); i++) {
 325                 if (req_mode < xfer_mode_bases[i])
 326                         continue;
 327                 mask = ide_get_mode_mask(drive, xfer_mode_bases[i], req_mode);
 328                 x = fls(mask) - 1;
 329                 if (x >= 0) {
 330                         mode = xfer_mode_bases[i] + x;
 331                         break;
 332                 }
 333         }
 334
 335         if (hwif->chipset == ide_acorn && mode == 0) {
 336                 /*
 337                  * is this correct?
 338                  */
 339                 if (ide_dma_good_drive(drive) &&
 340                     drive->id[ATA_ID_EIDE_DMA_TIME] < 150)
 341                         mode = XFER_MW_DMA_1;
 342         }
 343
 344         mode = min(mode, req_mode);
 345
 346         printk(KERN_INFO "%s: %s mode selected\n", drive->name,
 347                           mode ? ide_xfer_verbose(mode) : "no DMA");
 348
 349         return mode;
 350 }
 351 EXPORT_SYMBOL_GPL(ide_find_dma_mode);
 352
 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 (ide_id_dma_bug(drive))
 367                 return 0;
 368
 369         if (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA)
 370                 return config_drive_for_dma(drive);
 371
 372         speed = ide_max_dma_mode(drive);
 373
 374         if (!speed)
 375                 return 0;
 376
 377         if (ide_set_dma_mode(drive, speed))
 378                 return 0;
 379
 380         return 1;
 381 }
 382
 383 static int ide_dma_check(ide_drive_t *drive)
 384 {
 385         ide_hwif_t *hwif = drive->hwif;
 386
 387         if (ide_tune_dma(drive))
 388                 return 0;
 389
 390         /* TODO: always do PIO fallback */
 391         if (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA)
 392                 return -1;
 393
 394         ide_set_max_pio(drive);
 395
 396         return -1;
 397 }
 398
 399 int ide_id_dma_bug(ide_drive_t *drive)
 400 {
 401         u16 *id = drive->id;
 402
 403         if (id[ATA_ID_FIELD_VALID] & 4) {
 404                 if ((id[ATA_ID_UDMA_MODES] >> 8) &&
 405                     (id[ATA_ID_MWDMA_MODES] >> 8))
 406                         goto err_out;
 407         } else if (id[ATA_ID_FIELD_VALID] & 2) {
 408                 if ((id[ATA_ID_MWDMA_MODES] >> 8) &&
 409                     (id[ATA_ID_SWDMA_MODES] >> 8))
 410                         goto err_out;
 411         }
 412         return 0;
 413 err_out:
 414         printk(KERN_ERR "%s: bad DMA info in identify block\n", drive->name);
 415         return 1;
 416 }
 417
 418 int ide_set_dma(ide_drive_t *drive)
 419 {
 420         int rc;
 421
 422         /*
 423          * Force DMAing for the beginning of the check.
 424          * Some chipsets appear to do interesting
 425          * things, if not checked and cleared.
 426          *   PARANOIA!!!
 427          */
 428         ide_dma_off_quietly(drive);
 429
 430         rc = ide_dma_check(drive);
 431         if (rc)
 432                 return rc;
 433
 434         ide_dma_on(drive);
 435
 436         return 0;
 437 }
 438
 439 void ide_check_dma_crc(ide_drive_t *drive)
 440 {
 441         u8 mode;
 442
 443         ide_dma_off_quietly(drive);
 444         drive->crc_count = 0;
 445         mode = drive->current_speed;
 446         /*
 447          * Don't try non Ultra-DMA modes without iCRC's.  Force the
 448          * device to PIO and make the user enable SWDMA/MWDMA modes.
 449          */
 450         if (mode > XFER_UDMA_0 && mode <= XFER_UDMA_7)
 451                 mode--;
 452         else
 453                 mode = XFER_PIO_4;
 454         ide_set_xfer_rate(drive, mode);
 455         if (drive->current_speed >= XFER_SW_DMA_0)
 456                 ide_dma_on(drive);
 457 }
 458
 459 void ide_dma_lost_irq(ide_drive_t *drive)
 460 {
 461         printk(KERN_ERR "%s: DMA interrupt recovery\n", drive->name);
 462 }
 463 EXPORT_SYMBOL_GPL(ide_dma_lost_irq);
 464
 465 /*
 466  * un-busy the port etc, and clear any pending DMA status. we want to
 467  * retry the current request in pio mode instead of risking tossing it
 468  * all away
 469  */
 470 ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
 471 {
 472         ide_hwif_t *hwif = drive->hwif;
 473         const struct ide_dma_ops *dma_ops = hwif->dma_ops;
 474         struct request *rq;
 475         ide_startstop_t ret = ide_stopped;
 476
 477         /*
 478          * end current dma transaction
 479          */
 480
 481         if (error < 0) {
 482                 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name);
 483                 drive->waiting_for_dma = 0;
 484                 (void)dma_ops->dma_end(drive);
 485                 ide_destroy_dmatable(drive);
 486                 ret = ide_error(drive, "dma timeout error",
 487                                 hwif->tp_ops->read_status(hwif));
 488         } else {
 489                 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name);
 490                 if (dma_ops->dma_clear)
 491                         dma_ops->dma_clear(drive);
 492                 printk(KERN_ERR "%s: timeout waiting for DMA\n", drive->name);
 493                 if (dma_ops->dma_test_irq(drive) == 0) {
 494                         ide_dump_status(drive, "DMA timeout",
 495                                         hwif->tp_ops->read_status(hwif));
 496                         drive->waiting_for_dma = 0;
 497                         (void)dma_ops->dma_end(drive);
 498                         ide_destroy_dmatable(drive);
 499                 }
 500         }
 501
 502         /*
 503          * disable dma for now, but remember that we did so because of
 504          * a timeout -- we'll reenable after we finish this next request
 505          * (or rather the first chunk of it) in pio.
 506          */
 507         drive->dev_flags |= IDE_DFLAG_DMA_PIO_RETRY;
 508         drive->retry_pio++;
 509         ide_dma_off_quietly(drive);
 510
 511         /*
 512          * un-busy drive etc and make sure request is sane
 513          */
 514
 515         rq = hwif->rq;
 516         if (!rq)
 517                 goto out;
 518
 519         hwif->rq = NULL;
 520
 521         rq->errors = 0;
 522
 523         if (!rq->bio)
 524                 goto out;
 525
 526         rq->sector = rq->bio->bi_sector;
 527         rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9;
 528         rq->hard_cur_sectors = rq->current_nr_sectors;
 529         rq->buffer = bio_data(rq->bio);
 530 out:
 531         return ret;
 532 }
 533
 534 void ide_release_dma_engine(ide_hwif_t *hwif)
 535 {
 536         if (hwif->dmatable_cpu) {
 537                 int prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
 538
 539                 dma_free_coherent(hwif->dev, prd_size,
 540                                   hwif->dmatable_cpu, hwif->dmatable_dma);
 541                 hwif->dmatable_cpu = NULL;
 542         }
 543 }
 544 EXPORT_SYMBOL_GPL(ide_release_dma_engine);
 545
 546 int ide_allocate_dma_engine(ide_hwif_t *hwif)
 547 {
 548         int prd_size;
 549
 550         if (hwif->prd_max_nents == 0)
 551                 hwif->prd_max_nents = PRD_ENTRIES;
 552         if (hwif->prd_ent_size == 0)
 553                 hwif->prd_ent_size = PRD_BYTES;
 554
 555         prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
 556
 557         hwif->dmatable_cpu = dma_alloc_coherent(hwif->dev, prd_size,
 558                                                 &hwif->dmatable_dma,
 559                                                 GFP_ATOMIC);
 560         if (hwif->dmatable_cpu == NULL) {
 561                 printk(KERN_ERR "%s: unable to allocate PRD table\n",
 562                         hwif->name);
 563                 return -ENOMEM;
 564         }
 565
 566         return 0;
 567 }
 568 EXPORT_SYMBOL_GPL(ide_allocate_dma_engine);
 569
 570 int ide_dma_prepare(ide_drive_t *drive, struct ide_cmd *cmd)
 571 {
 572         const struct ide_dma_ops *dma_ops = drive->hwif->dma_ops;
 573
 574         if ((drive->dev_flags & IDE_DFLAG_USING_DMA) == 0 ||
 575             (dma_ops->dma_check && dma_ops->dma_check(drive, cmd)) ||
 576             ide_build_sglist(drive, cmd) == 0)
 577                 return 1;
 578         if (dma_ops->dma_setup(drive, cmd)) {
 579                 ide_destroy_dmatable(drive);
 580                 ide_map_sg(drive, cmd);
 581                 return 1;
 582         }
 583         drive->waiting_for_dma = 1;
 584         return 0;
 585 }