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/gfp.h>
  33 #include <linux/kernel.h>
  34 #include <linux/ide.h>
  35 #include <linux/scatterlist.h>
  36 #include <linux/dma-mapping.h>
  37
  38 static const struct drive_list_entry drive_whitelist[] = {
  39         { "Micropolis 2112A"    ,       NULL            },
  40         { "CONNER CTMA 4000"    ,       NULL            },
  41         { "CONNER CTT8000-A"    ,       NULL            },
  42         { "ST34342A"            ,       NULL            },
  43         { NULL                  ,       NULL            }
  44 };
  45
  46 static const struct drive_list_entry drive_blacklist[] = {
  47         { "WDC AC11000H"        ,       NULL            },
  48         { "WDC AC22100H"        ,       NULL            },
  49         { "WDC AC32500H"        ,       NULL            },
  50         { "WDC AC33100H"        ,       NULL            },
  51         { "WDC AC31600H"        ,       NULL            },
  52         { "WDC AC32100H"        ,       "24.09P07"      },
  53         { "WDC AC23200L"        ,       "21.10N21"      },
  54         { "Compaq CRD-8241B"    ,       NULL            },
  55         { "CRD-8400B"           ,       NULL            },
  56         { "CRD-8480B",                  NULL            },
  57         { "CRD-8482B",                  NULL            },
  58         { "CRD-84"              ,       NULL            },
  59         { "SanDisk SDP3B"       ,       NULL            },
  60         { "SanDisk SDP3B-64"    ,       NULL            },
  61         { "SANYO CD-ROM CRD"    ,       NULL            },
  62         { "HITACHI CDR-8"       ,       NULL            },
  63         { "HITACHI CDR-8335"    ,       NULL            },
  64         { "HITACHI CDR-8435"    ,       NULL            },
  65         { "Toshiba CD-ROM XM-6202B"     ,       NULL            },
  66         { "TOSHIBA CD-ROM XM-1702BC",   NULL            },
  67         { "CD-532E-A"           ,       NULL            },
  68         { "E-IDE CD-ROM CR-840",        NULL            },
  69         { "CD-ROM Drive/F5A",   NULL            },
  70         { "WPI CDD-820",                NULL            },
  71         { "SAMSUNG CD-ROM SC-148C",     NULL            },
  72         { "SAMSUNG CD-ROM SC",  NULL            },
  73         { "ATAPI CD-ROM DRIVE 40X MAXIMUM",     NULL            },
  74         { "_NEC DV5800A",               NULL            },
  75         { "SAMSUNG CD-ROM SN-124",      "N001" },
  76         { "Seagate STT20000A",          NULL  },
  77         { "CD-ROM CDR_U200",            "1.09" },
  78         { NULL                  ,       NULL            }
  79
  80 };
  81
  82 /**
  83  *      ide_dma_intr    -       IDE DMA interrupt handler
  84  *      @drive: the drive the interrupt is for
  85  *
  86  *      Handle an interrupt completing a read/write DMA transfer on an
  87  *      IDE device
  88  */
  89
  90 ide_startstop_t ide_dma_intr(ide_drive_t *drive)
  91 {
  92         ide_hwif_t *hwif = drive->hwif;
  93         struct ide_cmd *cmd = &hwif->cmd;
  94         u8 stat = 0, dma_stat = 0;
  95
  96         drive->waiting_for_dma = 0;
  97         dma_stat = hwif->dma_ops->dma_end(drive);
  98         ide_dma_unmap_sg(drive, cmd);
  99         stat = hwif->tp_ops->read_status(hwif);
 100
 101         if (OK_STAT(stat, DRIVE_READY, drive->bad_wstat | ATA_DRQ)) {
 102                 if (!dma_stat) {
 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                                                 blk_rq_sectors(cmd->rq) << 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_dma_map_sg  -       map IDE scatter gather for DMA I/O
 123  *      @drive: the drive to map 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_dma_map_sg(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         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) {
 145                 cmd->orig_sg_nents = cmd->sg_nents;
 146                 cmd->sg_nents = i;
 147         }
 148
 149         return i;
 150 }
 151
 152 /**
 153  *      ide_dma_unmap_sg        -       clean up DMA mapping
 154  *      @drive: The drive to unmap
 155  *
 156  *      Teardown mappings after DMA has completed. This must be called
 157  *      after the completion of each use of ide_build_dmatable and before
 158  *      the next use of ide_build_dmatable. Failure to do so will cause
 159  *      an oops as only one mapping can be live for each target at a given
 160  *      time.
 161  */
 162
 163 void ide_dma_unmap_sg(ide_drive_t *drive, struct ide_cmd *cmd)
 164 {
 165         ide_hwif_t *hwif = drive->hwif;
 166
 167         dma_unmap_sg(hwif->dev, hwif->sg_table, cmd->orig_sg_nents,
 168                      cmd->sg_dma_direction);
 169 }
 170 EXPORT_SYMBOL_GPL(ide_dma_unmap_sg);
 171
 172 /**
 173  *      ide_dma_off_quietly     -       Generic DMA kill
 174  *      @drive: drive to control
 175  *
 176  *      Turn off the current DMA on this IDE controller.
 177  */
 178
 179 void ide_dma_off_quietly(ide_drive_t *drive)
 180 {
 181         drive->dev_flags &= ~IDE_DFLAG_USING_DMA;
 182         ide_toggle_bounce(drive, 0);
 183
 184         drive->hwif->dma_ops->dma_host_set(drive, 0);
 185 }
 186 EXPORT_SYMBOL(ide_dma_off_quietly);
 187
 188 /**
 189  *      ide_dma_off     -       disable DMA on a device
 190  *      @drive: drive to disable DMA on
 191  *
 192  *      Disable IDE DMA for a device on this IDE controller.
 193  *      Inform the user that DMA has been disabled.
 194  */
 195
 196 void ide_dma_off(ide_drive_t *drive)
 197 {
 198         printk(KERN_INFO "%s: DMA disabled\n", drive->name);
 199         ide_dma_off_quietly(drive);
 200 }
 201 EXPORT_SYMBOL(ide_dma_off);
 202
 203 /**
 204  *      ide_dma_on              -       Enable DMA on a device
 205  *      @drive: drive to enable DMA on
 206  *
 207  *      Enable IDE DMA for a device on this IDE controller.
 208  */
 209
 210 void ide_dma_on(ide_drive_t *drive)
 211 {
 212         drive->dev_flags |= IDE_DFLAG_USING_DMA;
 213         ide_toggle_bounce(drive, 1);
 214
 215         drive->hwif->dma_ops->dma_host_set(drive, 1);
 216 }
 217
 218 int __ide_dma_bad_drive(ide_drive_t *drive)
 219 {
 220         u16 *id = drive->id;
 221
 222         int blacklist = ide_in_drive_list(id, drive_blacklist);
 223         if (blacklist) {
 224                 printk(KERN_WARNING "%s: Disabling (U)DMA for %s (blacklisted)\n",
 225                                     drive->name, (char *)&id[ATA_ID_PROD]);
 226                 return blacklist;
 227         }
 228         return 0;
 229 }
 230 EXPORT_SYMBOL(__ide_dma_bad_drive);
 231
 232 static const u8 xfer_mode_bases[] = {
 233         XFER_UDMA_0,
 234         XFER_MW_DMA_0,
 235         XFER_SW_DMA_0,
 236 };
 237
 238 static unsigned int ide_get_mode_mask(ide_drive_t *drive, u8 base, u8 req_mode)
 239 {
 240         u16 *id = drive->id;
 241         ide_hwif_t *hwif = drive->hwif;
 242         const struct ide_port_ops *port_ops = hwif->port_ops;
 243         unsigned int mask = 0;
 244
 245         switch (base) {
 246         case XFER_UDMA_0:
 247                 if ((id[ATA_ID_FIELD_VALID] & 4) == 0)
 248                         break;
 249                 mask = id[ATA_ID_UDMA_MODES];
 250                 if (port_ops && port_ops->udma_filter)
 251                         mask &= port_ops->udma_filter(drive);
 252                 else
 253                         mask &= hwif->ultra_mask;
 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                 mask = id[ATA_ID_MWDMA_MODES];
 265
 266                 /* Also look for the CF specific MWDMA modes... */
 267                 if (ata_id_is_cfa(id) && (id[ATA_ID_CFA_MODES] & 0x38)) {
 268                         u8 mode = ((id[ATA_ID_CFA_MODES] & 0x38) >> 3) - 1;
 269
 270                         mask |= ((2 << mode) - 1) << 3;
 271                 }
 272
 273                 if (port_ops && port_ops->mdma_filter)
 274                         mask &= port_ops->mdma_filter(drive);
 275                 else
 276                         mask &= hwif->mwdma_mask;
 277                 break;
 278         case XFER_SW_DMA_0:
 279                 mask = id[ATA_ID_SWDMA_MODES];
 280                 if (!(mask & ATA_SWDMA2) && (id[ATA_ID_OLD_DMA_MODES] >> 8)) {
 281                         u8 mode = id[ATA_ID_OLD_DMA_MODES] >> 8;
 282
 283                         /*
 284                          * if the mode is valid convert it to the mask
 285                          * (the maximum allowed mode is XFER_SW_DMA_2)
 286                          */
 287                         if (mode <= 2)
 288                                 mask = (2 << mode) - 1;
 289                 }
 290                 mask &= hwif->swdma_mask;
 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
 352 static int ide_tune_dma(ide_drive_t *drive)
 353 {
 354         ide_hwif_t *hwif = drive->hwif;
 355         u8 speed;
 356
 357         if (ata_id_has_dma(drive->id) == 0 ||
 358             (drive->dev_flags & IDE_DFLAG_NODMA))
 359                 return 0;
 360
 361         /* consult the list of known "bad" drives */
 362         if (__ide_dma_bad_drive(drive))
 363                 return 0;
 364
 365         if (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA)
 366                 return config_drive_for_dma(drive);
 367
 368         speed = ide_max_dma_mode(drive);
 369
 370         if (!speed)
 371                 return 0;
 372
 373         if (ide_set_dma_mode(drive, speed))
 374                 return 0;
 375
 376         return 1;
 377 }
 378
 379 static int ide_dma_check(ide_drive_t *drive)
 380 {
 381         ide_hwif_t *hwif = drive->hwif;
 382
 383         if (ide_tune_dma(drive))
 384                 return 0;
 385
 386         /* TODO: always do PIO fallback */
 387         if (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA)
 388                 return -1;
 389
 390         ide_set_max_pio(drive);
 391
 392         return -1;
 393 }
 394
 395 int ide_set_dma(ide_drive_t *drive)
 396 {
 397         int rc;
 398
 399         /*
 400          * Force DMAing for the beginning of the check.
 401          * Some chipsets appear to do interesting
 402          * things, if not checked and cleared.
 403          *   PARANOIA!!!
 404          */
 405         ide_dma_off_quietly(drive);
 406
 407         rc = ide_dma_check(drive);
 408         if (rc)
 409                 return rc;
 410
 411         ide_dma_on(drive);
 412
 413         return 0;
 414 }
 415
 416 void ide_check_dma_crc(ide_drive_t *drive)
 417 {
 418         u8 mode;
 419
 420         ide_dma_off_quietly(drive);
 421         drive->crc_count = 0;
 422         mode = drive->current_speed;
 423         /*
 424          * Don't try non Ultra-DMA modes without iCRC's.  Force the
 425          * device to PIO and make the user enable SWDMA/MWDMA modes.
 426          */
 427         if (mode > XFER_UDMA_0 && mode <= XFER_UDMA_7)
 428                 mode--;
 429         else
 430                 mode = XFER_PIO_4;
 431         ide_set_xfer_rate(drive, mode);
 432         if (drive->current_speed >= XFER_SW_DMA_0)
 433                 ide_dma_on(drive);
 434 }
 435
 436 void ide_dma_lost_irq(ide_drive_t *drive)
 437 {
 438         printk(KERN_ERR "%s: DMA interrupt recovery\n", drive->name);
 439 }
 440 EXPORT_SYMBOL_GPL(ide_dma_lost_irq);
 441
 442 /*
 443  * un-busy the port etc, and clear any pending DMA status. we want to
 444  * retry the current request in pio mode instead of risking tossing it
 445  * all away
 446  */
 447 ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
 448 {
 449         ide_hwif_t *hwif = drive->hwif;
 450         const struct ide_dma_ops *dma_ops = hwif->dma_ops;
 451         struct ide_cmd *cmd = &hwif->cmd;
 452         struct request *rq;
 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          * un-busy drive etc and make sure request is sane
 491          */
 492         rq = hwif->rq;
 493         if (rq) {
 494                 hwif->rq = NULL;
 495                 rq->errors = 0;
 496                 ide_requeue_and_plug(drive, rq);
 497         }
 498         return ret;
 499 }
 500
 501 void ide_release_dma_engine(ide_hwif_t *hwif)
 502 {
 503         if (hwif->dmatable_cpu) {
 504                 int prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
 505
 506                 dma_free_coherent(hwif->dev, prd_size,
 507                                   hwif->dmatable_cpu, hwif->dmatable_dma);
 508                 hwif->dmatable_cpu = NULL;
 509         }
 510 }
 511 EXPORT_SYMBOL_GPL(ide_release_dma_engine);
 512
 513 int ide_allocate_dma_engine(ide_hwif_t *hwif)
 514 {
 515         int prd_size;
 516
 517         if (hwif->prd_max_nents == 0)
 518                 hwif->prd_max_nents = PRD_ENTRIES;
 519         if (hwif->prd_ent_size == 0)
 520                 hwif->prd_ent_size = PRD_BYTES;
 521
 522         prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
 523
 524         hwif->dmatable_cpu = dma_alloc_coherent(hwif->dev, prd_size,
 525                                                 &hwif->dmatable_dma,
 526                                                 GFP_ATOMIC);
 527         if (hwif->dmatable_cpu == NULL) {
 528                 printk(KERN_ERR "%s: unable to allocate PRD table\n",
 529                         hwif->name);
 530                 return -ENOMEM;
 531         }
 532
 533         return 0;
 534 }
 535 EXPORT_SYMBOL_GPL(ide_allocate_dma_engine);
 536
 537 int ide_dma_prepare(ide_drive_t *drive, struct ide_cmd *cmd)
 538 {
 539         const struct ide_dma_ops *dma_ops = drive->hwif->dma_ops;
 540
 541         if ((drive->dev_flags & IDE_DFLAG_USING_DMA) == 0 ||
 542             (dma_ops->dma_check && dma_ops->dma_check(drive, cmd)))
 543                 goto out;
 544         ide_map_sg(drive, cmd);
 545         if (ide_dma_map_sg(drive, cmd) == 0)
 546                 goto out_map;
 547         if (dma_ops->dma_setup(drive, cmd))
 548                 goto out_dma_unmap;
 549         drive->waiting_for_dma = 1;
 550         return 0;
 551 out_dma_unmap:
 552         ide_dma_unmap_sg(drive, cmd);
 553 out_map:
 554         ide_map_sg(drive, cmd);
 555 out:
 556         return 1;
 557 }