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                         if ((cmd->tf_flags & IDE_TFLAG_FS) == 0)
 102                                 ide_finish_cmd(drive, cmd, stat);
 103                         else
 104                                 ide_complete_rq(drive, 0,
 105                                                 cmd->rq->nr_sectors << 9);
 106                         return ide_stopped;
 107                 }
 108                 printk(KERN_ERR "%s: %s: bad DMA status (0x%02x)\n",
 109                         drive->name, __func__, dma_stat);
 110         }
 111         return ide_error(drive, "dma_intr", stat);
 112 }
 113
 114 int ide_dma_good_drive(ide_drive_t *drive)
 115 {
 116         return ide_in_drive_list(drive->id, drive_whitelist);
 117 }
 118
 119 /**
 120  *      ide_build_sglist        -       map IDE scatter gather for DMA I/O
 121  *      @drive: the drive to build the DMA table for
 122  *      @cmd: command
 123  *
 124  *      Perform the DMA mapping magic necessary to access the source or
 125  *      target buffers of a request via DMA.  The lower layers of the
 126  *      kernel provide the necessary cache management so that we can
 127  *      operate in a portable fashion.
 128  */
 129
 130 int ide_build_sglist(ide_drive_t *drive, struct ide_cmd *cmd)
 131 {
 132         ide_hwif_t *hwif = drive->hwif;
 133         struct scatterlist *sg = hwif->sg_table;
 134         int i;
 135
 136         ide_map_sg(drive, cmd);
 137
 138         if (cmd->tf_flags & IDE_TFLAG_WRITE)
 139                 cmd->sg_dma_direction = DMA_TO_DEVICE;
 140         else
 141                 cmd->sg_dma_direction = DMA_FROM_DEVICE;
 142
 143         i = dma_map_sg(hwif->dev, sg, cmd->sg_nents, cmd->sg_dma_direction);
 144         if (i == 0)
 145                 ide_map_sg(drive, cmd);
 146         else {
 147                 cmd->orig_sg_nents = cmd->sg_nents;
 148                 cmd->sg_nents = i;
 149         }
 150
 151         return i;
 152 }
 153
 154 /**
 155  *      ide_destroy_dmatable    -       clean up DMA mapping
 156  *      @drive: The drive to unmap
 157  *
 158  *      Teardown mappings after DMA has completed. This must be called
 159  *      after the completion of each use of ide_build_dmatable and before
 160  *      the next use of ide_build_dmatable. Failure to do so will cause
 161  *      an oops as only one mapping can be live for each target at a given
 162  *      time.
 163  */
 164
 165 void ide_destroy_dmatable(ide_drive_t *drive)
 166 {
 167         ide_hwif_t *hwif = drive->hwif;
 168         struct ide_cmd *cmd = &hwif->cmd;
 169
 170         dma_unmap_sg(hwif->dev, hwif->sg_table, cmd->orig_sg_nents,
 171                      cmd->sg_dma_direction);
 172 }
 173 EXPORT_SYMBOL_GPL(ide_destroy_dmatable);
 174
 175 /**
 176  *      ide_dma_off_quietly     -       Generic DMA kill
 177  *      @drive: drive to control
 178  *
 179  *      Turn off the current DMA on this IDE controller.
 180  */
 181
 182 void ide_dma_off_quietly(ide_drive_t *drive)
 183 {
 184         drive->dev_flags &= ~IDE_DFLAG_USING_DMA;
 185         ide_toggle_bounce(drive, 0);
 186
 187         drive->hwif->dma_ops->dma_host_set(drive, 0);
 188 }
 189 EXPORT_SYMBOL(ide_dma_off_quietly);
 190
 191 /**
 192  *      ide_dma_off     -       disable DMA on a device
 193  *      @drive: drive to disable DMA on
 194  *
 195  *      Disable IDE DMA for a device on this IDE controller.
 196  *      Inform the user that DMA has been disabled.
 197  */
 198
 199 void ide_dma_off(ide_drive_t *drive)
 200 {
 201         printk(KERN_INFO "%s: DMA disabled\n", drive->name);
 202         ide_dma_off_quietly(drive);
 203 }
 204 EXPORT_SYMBOL(ide_dma_off);
 205
 206 /**
 207  *      ide_dma_on              -       Enable DMA on a device
 208  *      @drive: drive to enable DMA on
 209  *
 210  *      Enable IDE DMA for a device on this IDE controller.
 211  */
 212
 213 void ide_dma_on(ide_drive_t *drive)
 214 {
 215         drive->dev_flags |= IDE_DFLAG_USING_DMA;
 216         ide_toggle_bounce(drive, 1);
 217
 218         drive->hwif->dma_ops->dma_host_set(drive, 1);
 219 }
 220
 221 int __ide_dma_bad_drive(ide_drive_t *drive)
 222 {
 223         u16 *id = drive->id;
 224
 225         int blacklist = ide_in_drive_list(id, drive_blacklist);
 226         if (blacklist) {
 227                 printk(KERN_WARNING "%s: Disabling (U)DMA for %s (blacklisted)\n",
 228                                     drive->name, (char *)&id[ATA_ID_PROD]);
 229                 return blacklist;
 230         }
 231         return 0;
 232 }
 233 EXPORT_SYMBOL(__ide_dma_bad_drive);
 234
 235 static const u8 xfer_mode_bases[] = {
 236         XFER_UDMA_0,
 237         XFER_MW_DMA_0,
 238         XFER_SW_DMA_0,
 239 };
 240
 241 static unsigned int ide_get_mode_mask(ide_drive_t *drive, u8 base, u8 req_mode)
 242 {
 243         u16 *id = drive->id;
 244         ide_hwif_t *hwif = drive->hwif;
 245         const struct ide_port_ops *port_ops = hwif->port_ops;
 246         unsigned int mask = 0;
 247
 248         switch (base) {
 249         case XFER_UDMA_0:
 250                 if ((id[ATA_ID_FIELD_VALID] & 4) == 0)
 251                         break;
 252
 253                 if (port_ops && port_ops->udma_filter)
 254                         mask = port_ops->udma_filter(drive);
 255                 else
 256                         mask = hwif->ultra_mask;
 257                 mask &= id[ATA_ID_UDMA_MODES];
 258
 259                 /*
 260                  * avoid false cable warning from eighty_ninty_three()
 261                  */
 262                 if (req_mode > XFER_UDMA_2) {
 263                         if ((mask & 0x78) && (eighty_ninty_three(drive) == 0))
 264                                 mask &= 0x07;
 265                 }
 266                 break;
 267         case XFER_MW_DMA_0:
 268                 if ((id[ATA_ID_FIELD_VALID] & 2) == 0)
 269                         break;
 270                 if (port_ops && port_ops->mdma_filter)
 271                         mask = port_ops->mdma_filter(drive);
 272                 else
 273                         mask = hwif->mwdma_mask;
 274                 mask &= id[ATA_ID_MWDMA_MODES];
 275                 break;
 276         case XFER_SW_DMA_0:
 277                 if (id[ATA_ID_FIELD_VALID] & 2) {
 278                         mask = id[ATA_ID_SWDMA_MODES] & hwif->swdma_mask;
 279                 } else if (id[ATA_ID_OLD_DMA_MODES] >> 8) {
 280                         u8 mode = id[ATA_ID_OLD_DMA_MODES] >> 8;
 281
 282                         /*
 283                          * if the mode is valid convert it to the mask
 284                          * (the maximum allowed mode is XFER_SW_DMA_2)
 285                          */
 286                         if (mode <= 2)
 287                                 mask = ((2 << mode) - 1) & hwif->swdma_mask;
 288                 }
 289                 break;
 290         default:
 291                 BUG();
 292                 break;
 293         }
 294
 295         return mask;
 296 }
 297
 298 /**
 299  *      ide_find_dma_mode       -       compute DMA speed
 300  *      @drive: IDE device
 301  *      @req_mode: requested mode
 302  *
 303  *      Checks the drive/host capabilities and finds the speed to use for
 304  *      the DMA transfer.  The speed is then limited by the requested mode.
 305  *
 306  *      Returns 0 if the drive/host combination is incapable of DMA transfers
 307  *      or if the requested mode is not a DMA mode.
 308  */
 309
 310 u8 ide_find_dma_mode(ide_drive_t *drive, u8 req_mode)
 311 {
 312         ide_hwif_t *hwif = drive->hwif;
 313         unsigned int mask;
 314         int x, i;
 315         u8 mode = 0;
 316
 317         if (drive->media != ide_disk) {
 318                 if (hwif->host_flags & IDE_HFLAG_NO_ATAPI_DMA)
 319                         return 0;
 320         }
 321
 322         for (i = 0; i < ARRAY_SIZE(xfer_mode_bases); i++) {
 323                 if (req_mode < xfer_mode_bases[i])
 324                         continue;
 325                 mask = ide_get_mode_mask(drive, xfer_mode_bases[i], req_mode);
 326                 x = fls(mask) - 1;
 327                 if (x >= 0) {
 328                         mode = xfer_mode_bases[i] + x;
 329                         break;
 330                 }
 331         }
 332
 333         if (hwif->chipset == ide_acorn && mode == 0) {
 334                 /*
 335                  * is this correct?
 336                  */
 337                 if (ide_dma_good_drive(drive) &&
 338                     drive->id[ATA_ID_EIDE_DMA_TIME] < 150)
 339                         mode = XFER_MW_DMA_1;
 340         }
 341
 342         mode = min(mode, req_mode);
 343
 344         printk(KERN_INFO "%s: %s mode selected\n", drive->name,
 345                           mode ? ide_xfer_verbose(mode) : "no DMA");
 346
 347         return mode;
 348 }
 349 EXPORT_SYMBOL_GPL(ide_find_dma_mode);
 350
 351 static int ide_tune_dma(ide_drive_t *drive)
 352 {
 353         ide_hwif_t *hwif = drive->hwif;
 354         u8 speed;
 355
 356         if (ata_id_has_dma(drive->id) == 0 ||
 357             (drive->dev_flags & IDE_DFLAG_NODMA))
 358                 return 0;
 359
 360         /* consult the list of known "bad" drives */
 361         if (__ide_dma_bad_drive(drive))
 362                 return 0;
 363
 364         if (ide_id_dma_bug(drive))
 365                 return 0;
 366
 367         if (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA)
 368                 return config_drive_for_dma(drive);
 369
 370         speed = ide_max_dma_mode(drive);
 371
 372         if (!speed)
 373                 return 0;
 374
 375         if (ide_set_dma_mode(drive, speed))
 376                 return 0;
 377
 378         return 1;
 379 }
 380
 381 static int ide_dma_check(ide_drive_t *drive)
 382 {
 383         ide_hwif_t *hwif = drive->hwif;
 384
 385         if (ide_tune_dma(drive))
 386                 return 0;
 387
 388         /* TODO: always do PIO fallback */
 389         if (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA)
 390                 return -1;
 391
 392         ide_set_max_pio(drive);
 393
 394         return -1;
 395 }
 396
 397 int ide_id_dma_bug(ide_drive_t *drive)
 398 {
 399         u16 *id = drive->id;
 400
 401         if (id[ATA_ID_FIELD_VALID] & 4) {
 402                 if ((id[ATA_ID_UDMA_MODES] >> 8) &&
 403                     (id[ATA_ID_MWDMA_MODES] >> 8))
 404                         goto err_out;
 405         } else if (id[ATA_ID_FIELD_VALID] & 2) {
 406                 if ((id[ATA_ID_MWDMA_MODES] >> 8) &&
 407                     (id[ATA_ID_SWDMA_MODES] >> 8))
 408                         goto err_out;
 409         }
 410         return 0;
 411 err_out:
 412         printk(KERN_ERR "%s: bad DMA info in identify block\n", drive->name);
 413         return 1;
 414 }
 415
 416 int ide_set_dma(ide_drive_t *drive)
 417 {
 418         int rc;
 419
 420         /*
 421          * Force DMAing for the beginning of the check.
 422          * Some chipsets appear to do interesting
 423          * things, if not checked and cleared.
 424          *   PARANOIA!!!
 425          */
 426         ide_dma_off_quietly(drive);
 427
 428         rc = ide_dma_check(drive);
 429         if (rc)
 430                 return rc;
 431
 432         ide_dma_on(drive);
 433
 434         return 0;
 435 }
 436
 437 void ide_check_dma_crc(ide_drive_t *drive)
 438 {
 439         u8 mode;
 440
 441         ide_dma_off_quietly(drive);
 442         drive->crc_count = 0;
 443         mode = drive->current_speed;
 444         /*
 445          * Don't try non Ultra-DMA modes without iCRC's.  Force the
 446          * device to PIO and make the user enable SWDMA/MWDMA modes.
 447          */
 448         if (mode > XFER_UDMA_0 && mode <= XFER_UDMA_7)
 449                 mode--;
 450         else
 451                 mode = XFER_PIO_4;
 452         ide_set_xfer_rate(drive, mode);
 453         if (drive->current_speed >= XFER_SW_DMA_0)
 454                 ide_dma_on(drive);
 455 }
 456
 457 void ide_dma_lost_irq(ide_drive_t *drive)
 458 {
 459         printk(KERN_ERR "%s: DMA interrupt recovery\n", drive->name);
 460 }
 461 EXPORT_SYMBOL_GPL(ide_dma_lost_irq);
 462
 463 static void ide_dma_timeout(ide_drive_t *drive)
 464 {
 465         ide_hwif_t *hwif = drive->hwif;
 466
 467         printk(KERN_ERR "%s: timeout waiting for DMA\n", drive->name);
 468
 469         if (hwif->dma_ops->dma_test_irq(drive))
 470                 return;
 471
 472         ide_dump_status(drive, "DMA timeout", hwif->tp_ops->read_status(hwif));
 473
 474         hwif->dma_ops->dma_end(drive);
 475 }
 476
 477 /*
 478  * un-busy the port etc, and clear any pending DMA status. we want to
 479  * retry the current request in pio mode instead of risking tossing it
 480  * all away
 481  */
 482 ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
 483 {
 484         ide_hwif_t *hwif = drive->hwif;
 485         const struct ide_dma_ops *dma_ops = hwif->dma_ops;
 486         struct request *rq;
 487         ide_startstop_t ret = ide_stopped;
 488
 489         /*
 490          * end current dma transaction
 491          */
 492
 493         if (error < 0) {
 494                 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name);
 495                 (void)dma_ops->dma_end(drive);
 496                 ret = ide_error(drive, "dma timeout error",
 497                                 hwif->tp_ops->read_status(hwif));
 498         } else {
 499                 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name);
 500                 if (dma_ops->dma_clear)
 501                         dma_ops->dma_clear(drive);
 502                 ide_dma_timeout(drive);
 503         }
 504
 505         /*
 506          * disable dma for now, but remember that we did so because of
 507          * a timeout -- we'll reenable after we finish this next request
 508          * (or rather the first chunk of it) in pio.
 509          */
 510         drive->dev_flags |= IDE_DFLAG_DMA_PIO_RETRY;
 511         drive->retry_pio++;
 512         ide_dma_off_quietly(drive);
 513
 514         /*
 515          * un-busy drive etc and make sure request is sane
 516          */
 517
 518         rq = hwif->rq;
 519         if (!rq)
 520                 goto out;
 521
 522         hwif->rq = NULL;
 523
 524         rq->errors = 0;
 525
 526         if (!rq->bio)
 527                 goto out;
 528
 529         rq->sector = rq->bio->bi_sector;
 530         rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9;
 531         rq->hard_cur_sectors = rq->current_nr_sectors;
 532         rq->buffer = bio_data(rq->bio);
 533 out:
 534         return ret;
 535 }
 536
 537 void ide_release_dma_engine(ide_hwif_t *hwif)
 538 {
 539         if (hwif->dmatable_cpu) {
 540                 int prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
 541
 542                 dma_free_coherent(hwif->dev, prd_size,
 543                                   hwif->dmatable_cpu, hwif->dmatable_dma);
 544                 hwif->dmatable_cpu = NULL;
 545         }
 546 }
 547 EXPORT_SYMBOL_GPL(ide_release_dma_engine);
 548
 549 int ide_allocate_dma_engine(ide_hwif_t *hwif)
 550 {
 551         int prd_size;
 552
 553         if (hwif->prd_max_nents == 0)
 554                 hwif->prd_max_nents = PRD_ENTRIES;
 555         if (hwif->prd_ent_size == 0)
 556                 hwif->prd_ent_size = PRD_BYTES;
 557
 558         prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
 559
 560         hwif->dmatable_cpu = dma_alloc_coherent(hwif->dev, prd_size,
 561                                                 &hwif->dmatable_dma,
 562                                                 GFP_ATOMIC);
 563         if (hwif->dmatable_cpu == NULL) {
 564                 printk(KERN_ERR "%s: unable to allocate PRD table\n",
 565                         hwif->name);
 566                 return -ENOMEM;
 567         }
 568
 569         return 0;
 570 }
 571 EXPORT_SYMBOL_GPL(ide_allocate_dma_engine);