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         struct ide_cmd *cmd = &hwif->cmd;
  93         u8 stat = 0, dma_stat = 0;
  94
  95         drive->waiting_for_dma = 0;
  96         dma_stat = hwif->dma_ops->dma_end(drive);
  97         ide_dma_unmap_sg(drive, cmd);
  98         stat = hwif->tp_ops->read_status(hwif);
  99
 100         if (OK_STAT(stat, DRIVE_READY, drive->bad_wstat | ATA_DRQ)) {
 101                 if (!dma_stat) {
 102                         if ((cmd->tf_flags & IDE_TFLAG_FS) == 0)
 103                                 ide_finish_cmd(drive, cmd, stat);
 104                         else
 105                                 ide_complete_rq(drive, 0,
 106                                                 blk_rq_sectors(cmd->rq) << 9);
 107                         return ide_stopped;
 108                 }
 109                 printk(KERN_ERR "%s: %s: bad DMA status (0x%02x)\n",
 110                         drive->name, __func__, dma_stat);
 111         }
 112         return ide_error(drive, "dma_intr", stat);
 113 }
 114
 115 int ide_dma_good_drive(ide_drive_t *drive)
 116 {
 117         return ide_in_drive_list(drive->id, drive_whitelist);
 118 }
 119
 120 /**
 121  *      ide_dma_map_sg  -       map IDE scatter gather for DMA I/O
 122  *      @drive: the drive to map the DMA table for
 123  *      @cmd: command
 124  *
 125  *      Perform the DMA mapping magic necessary to access the source or
 126  *      target buffers of a request via DMA.  The lower layers of the
 127  *      kernel provide the necessary cache management so that we can
 128  *      operate in a portable fashion.
 129  */
 130
 131 static int ide_dma_map_sg(ide_drive_t *drive, struct ide_cmd *cmd)
 132 {
 133         ide_hwif_t *hwif = drive->hwif;
 134         struct scatterlist *sg = hwif->sg_table;
 135         int i;
 136
 137         if (cmd->tf_flags & IDE_TFLAG_WRITE)
 138                 cmd->sg_dma_direction = DMA_TO_DEVICE;
 139         else
 140                 cmd->sg_dma_direction = DMA_FROM_DEVICE;
 141
 142         i = dma_map_sg(hwif->dev, sg, cmd->sg_nents, cmd->sg_dma_direction);
 143         if (i) {
 144                 cmd->orig_sg_nents = cmd->sg_nents;
 145                 cmd->sg_nents = i;
 146         }
 147
 148         return i;
 149 }
 150
 151 /**
 152  *      ide_dma_unmap_sg        -       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_dma_unmap_sg(ide_drive_t *drive, struct ide_cmd *cmd)
 163 {
 164         ide_hwif_t *hwif = drive->hwif;
 165
 166         dma_unmap_sg(hwif->dev, hwif->sg_table, cmd->orig_sg_nents,
 167                      cmd->sg_dma_direction);
 168 }
 169 EXPORT_SYMBOL_GPL(ide_dma_unmap_sg);
 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                 mask = id[ATA_ID_UDMA_MODES];
 249                 if (port_ops && port_ops->udma_filter)
 250                         mask &= port_ops->udma_filter(drive);
 251                 else
 252                         mask &= hwif->ultra_mask;
 253
 254                 /*
 255                  * avoid false cable warning from eighty_ninty_three()
 256                  */
 257                 if (req_mode > XFER_UDMA_2) {
 258                         if ((mask & 0x78) && (eighty_ninty_three(drive) == 0))
 259                                 mask &= 0x07;
 260                 }
 261                 break;
 262         case XFER_MW_DMA_0:
 263                 mask = id[ATA_ID_MWDMA_MODES];
 264
 265                 /* Also look for the CF specific MWDMA modes... */
 266                 if (ata_id_is_cfa(id) && (id[ATA_ID_CFA_MODES] & 0x38)) {
 267                         u8 mode = ((id[ATA_ID_CFA_MODES] & 0x38) >> 3) - 1;
 268
 269                         mask |= ((2 << mode) - 1) << 3;
 270                 }
 271
 272                 if (port_ops && port_ops->mdma_filter)
 273                         mask &= port_ops->mdma_filter(drive);
 274                 else
 275                         mask &= hwif->mwdma_mask;
 276                 break;
 277         case XFER_SW_DMA_0:
 278                 mask = id[ATA_ID_SWDMA_MODES];
 279                 if (!(mask & ATA_SWDMA2) && (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;
 288                 }
 289                 mask &= hwif->swdma_mask;
 290                 break;
 291         default:
 292                 BUG();
 293                 break;
 294         }
 295
 296         return mask;
 297 }
 298
 299 /**
 300  *      ide_find_dma_mode       -       compute DMA speed
 301  *      @drive: IDE device
 302  *      @req_mode: requested mode
 303  *
 304  *      Checks the drive/host capabilities and finds the speed to use for
 305  *      the DMA transfer.  The speed is then limited by the requested mode.
 306  *
 307  *      Returns 0 if the drive/host combination is incapable of DMA transfers
 308  *      or if the requested mode is not a DMA mode.
 309  */
 310
 311 u8 ide_find_dma_mode(ide_drive_t *drive, u8 req_mode)
 312 {
 313         ide_hwif_t *hwif = drive->hwif;
 314         unsigned int mask;
 315         int x, i;
 316         u8 mode = 0;
 317
 318         if (drive->media != ide_disk) {
 319                 if (hwif->host_flags & IDE_HFLAG_NO_ATAPI_DMA)
 320                         return 0;
 321         }
 322
 323         for (i = 0; i < ARRAY_SIZE(xfer_mode_bases); i++) {
 324                 if (req_mode < xfer_mode_bases[i])
 325                         continue;
 326                 mask = ide_get_mode_mask(drive, xfer_mode_bases[i], req_mode);
 327                 x = fls(mask) - 1;
 328                 if (x >= 0) {
 329                         mode = xfer_mode_bases[i] + x;
 330                         break;
 331                 }
 332         }
 333
 334         if (hwif->chipset == ide_acorn && mode == 0) {
 335                 /*
 336                  * is this correct?
 337                  */
 338                 if (ide_dma_good_drive(drive) &&
 339                     drive->id[ATA_ID_EIDE_DMA_TIME] < 150)
 340                         mode = XFER_MW_DMA_1;
 341         }
 342
 343         mode = min(mode, req_mode);
 344
 345         printk(KERN_INFO "%s: %s mode selected\n", drive->name,
 346                           mode ? ide_xfer_verbose(mode) : "no DMA");
 347
 348         return mode;
 349 }
 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_MWDMA_MODES] >> 8) &&
 406                    (id[ATA_ID_SWDMA_MODES] >> 8))
 407                 goto err_out;
 408
 409         return 0;
 410 err_out:
 411         printk(KERN_ERR "%s: bad DMA info in identify block\n", drive->name);
 412         return 1;
 413 }
 414
 415 int ide_set_dma(ide_drive_t *drive)
 416 {
 417         int rc;
 418
 419         /*
 420          * Force DMAing for the beginning of the check.
 421          * Some chipsets appear to do interesting
 422          * things, if not checked and cleared.
 423          *   PARANOIA!!!
 424          */
 425         ide_dma_off_quietly(drive);
 426
 427         rc = ide_dma_check(drive);
 428         if (rc)
 429                 return rc;
 430
 431         ide_dma_on(drive);
 432
 433         return 0;
 434 }
 435
 436 void ide_check_dma_crc(ide_drive_t *drive)
 437 {
 438         u8 mode;
 439
 440         ide_dma_off_quietly(drive);
 441         drive->crc_count = 0;
 442         mode = drive->current_speed;
 443         /*
 444          * Don't try non Ultra-DMA modes without iCRC's.  Force the
 445          * device to PIO and make the user enable SWDMA/MWDMA modes.
 446          */
 447         if (mode > XFER_UDMA_0 && mode <= XFER_UDMA_7)
 448                 mode--;
 449         else
 450                 mode = XFER_PIO_4;
 451         ide_set_xfer_rate(drive, mode);
 452         if (drive->current_speed >= XFER_SW_DMA_0)
 453                 ide_dma_on(drive);
 454 }
 455
 456 void ide_dma_lost_irq(ide_drive_t *drive)
 457 {
 458         printk(KERN_ERR "%s: DMA interrupt recovery\n", drive->name);
 459 }
 460 EXPORT_SYMBOL_GPL(ide_dma_lost_irq);
 461
 462 /*
 463  * un-busy the port etc, and clear any pending DMA status. we want to
 464  * retry the current request in pio mode instead of risking tossing it
 465  * all away
 466  */
 467 ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
 468 {
 469         ide_hwif_t *hwif = drive->hwif;
 470         const struct ide_dma_ops *dma_ops = hwif->dma_ops;
 471         struct ide_cmd *cmd = &hwif->cmd;
 472         struct request *rq;
 473         ide_startstop_t ret = ide_stopped;
 474
 475         /*
 476          * end current dma transaction
 477          */
 478
 479         if (error < 0) {
 480                 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name);
 481                 drive->waiting_for_dma = 0;
 482                 (void)dma_ops->dma_end(drive);
 483                 ide_dma_unmap_sg(drive, cmd);
 484                 ret = ide_error(drive, "dma timeout error",
 485                                 hwif->tp_ops->read_status(hwif));
 486         } else {
 487                 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name);
 488                 if (dma_ops->dma_clear)
 489                         dma_ops->dma_clear(drive);
 490                 printk(KERN_ERR "%s: timeout waiting for DMA\n", drive->name);
 491                 if (dma_ops->dma_test_irq(drive) == 0) {
 492                         ide_dump_status(drive, "DMA timeout",
 493                                         hwif->tp_ops->read_status(hwif));
 494                         drive->waiting_for_dma = 0;
 495                         (void)dma_ops->dma_end(drive);
 496                         ide_dma_unmap_sg(drive, cmd);
 497                 }
 498         }
 499
 500         /*
 501          * disable dma for now, but remember that we did so because of
 502          * a timeout -- we'll reenable after we finish this next request
 503          * (or rather the first chunk of it) in pio.
 504          */
 505         drive->dev_flags |= IDE_DFLAG_DMA_PIO_RETRY;
 506         drive->retry_pio++;
 507         ide_dma_off_quietly(drive);
 508
 509         /*
 510          * un-busy drive etc and make sure request is sane
 511          */
 512         rq = hwif->rq;
 513         if (rq) {
 514                 hwif->rq = NULL;
 515                 rq->errors = 0;
 516         }
 517         return ret;
 518 }
 519
 520 void ide_release_dma_engine(ide_hwif_t *hwif)
 521 {
 522         if (hwif->dmatable_cpu) {
 523                 int prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
 524
 525                 dma_free_coherent(hwif->dev, prd_size,
 526                                   hwif->dmatable_cpu, hwif->dmatable_dma);
 527                 hwif->dmatable_cpu = NULL;
 528         }
 529 }
 530 EXPORT_SYMBOL_GPL(ide_release_dma_engine);
 531
 532 int ide_allocate_dma_engine(ide_hwif_t *hwif)
 533 {
 534         int prd_size;
 535
 536         if (hwif->prd_max_nents == 0)
 537                 hwif->prd_max_nents = PRD_ENTRIES;
 538         if (hwif->prd_ent_size == 0)
 539                 hwif->prd_ent_size = PRD_BYTES;
 540
 541         prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
 542
 543         hwif->dmatable_cpu = dma_alloc_coherent(hwif->dev, prd_size,
 544                                                 &hwif->dmatable_dma,
 545                                                 GFP_ATOMIC);
 546         if (hwif->dmatable_cpu == NULL) {
 547                 printk(KERN_ERR "%s: unable to allocate PRD table\n",
 548                         hwif->name);
 549                 return -ENOMEM;
 550         }
 551
 552         return 0;
 553 }
 554 EXPORT_SYMBOL_GPL(ide_allocate_dma_engine);
 555
 556 int ide_dma_prepare(ide_drive_t *drive, struct ide_cmd *cmd)
 557 {
 558         const struct ide_dma_ops *dma_ops = drive->hwif->dma_ops;
 559
 560         if ((drive->dev_flags & IDE_DFLAG_USING_DMA) == 0 ||
 561             (dma_ops->dma_check && dma_ops->dma_check(drive, cmd)))
 562                 goto out;
 563         ide_map_sg(drive, cmd);
 564         if (ide_dma_map_sg(drive, cmd) == 0)
 565                 goto out_map;
 566         if (dma_ops->dma_setup(drive, cmd))
 567                 goto out_dma_unmap;
 568         drive->waiting_for_dma = 1;
 569         return 0;
 570 out_dma_unmap:
 571         ide_dma_unmap_sg(drive, cmd);
 572 out_map:
 573         ide_map_sg(drive, cmd);
 574 out:
 575         return 1;
 576 }