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 request *rq = hwif->rq;
 100
 101                         task_end_request(drive, rq, 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) {
 142                 hwif->orig_sg_nents = hwif->sg_nents;
 143                 hwif->sg_nents = i;
 144         }
 145
 146         return i;
 147 }
 148 EXPORT_SYMBOL_GPL(ide_build_sglist);
 149
 150 /**
 151  *      ide_destroy_dmatable    -       clean up DMA mapping
 152  *      @drive: The drive to unmap
 153  *
 154  *      Teardown mappings after DMA has completed. This must be called
 155  *      after the completion of each use of ide_build_dmatable and before
 156  *      the next use of ide_build_dmatable. Failure to do so will cause
 157  *      an oops as only one mapping can be live for each target at a given
 158  *      time.
 159  */
 160
 161 void ide_destroy_dmatable(ide_drive_t *drive)
 162 {
 163         ide_hwif_t *hwif = drive->hwif;
 164
 165         dma_unmap_sg(hwif->dev, hwif->sg_table, hwif->orig_sg_nents,
 166                      hwif->sg_dma_direction);
 167 }
 168 EXPORT_SYMBOL_GPL(ide_destroy_dmatable);
 169
 170 /**
 171  *      ide_dma_off_quietly     -       Generic DMA kill
 172  *      @drive: drive to control
 173  *
 174  *      Turn off the current DMA on this IDE controller.
 175  */
 176
 177 void ide_dma_off_quietly(ide_drive_t *drive)
 178 {
 179         drive->dev_flags &= ~IDE_DFLAG_USING_DMA;
 180         ide_toggle_bounce(drive, 0);
 181
 182         drive->hwif->dma_ops->dma_host_set(drive, 0);
 183 }
 184 EXPORT_SYMBOL(ide_dma_off_quietly);
 185
 186 /**
 187  *      ide_dma_off     -       disable DMA on a device
 188  *      @drive: drive to disable DMA on
 189  *
 190  *      Disable IDE DMA for a device on this IDE controller.
 191  *      Inform the user that DMA has been disabled.
 192  */
 193
 194 void ide_dma_off(ide_drive_t *drive)
 195 {
 196         printk(KERN_INFO "%s: DMA disabled\n", drive->name);
 197         ide_dma_off_quietly(drive);
 198 }
 199 EXPORT_SYMBOL(ide_dma_off);
 200
 201 /**
 202  *      ide_dma_on              -       Enable DMA on a device
 203  *      @drive: drive to enable DMA on
 204  *
 205  *      Enable IDE DMA for a device on this IDE controller.
 206  */
 207
 208 void ide_dma_on(ide_drive_t *drive)
 209 {
 210         drive->dev_flags |= IDE_DFLAG_USING_DMA;
 211         ide_toggle_bounce(drive, 1);
 212
 213         drive->hwif->dma_ops->dma_host_set(drive, 1);
 214 }
 215
 216 int __ide_dma_bad_drive(ide_drive_t *drive)
 217 {
 218         u16 *id = drive->id;
 219
 220         int blacklist = ide_in_drive_list(id, drive_blacklist);
 221         if (blacklist) {
 222                 printk(KERN_WARNING "%s: Disabling (U)DMA for %s (blacklisted)\n",
 223                                     drive->name, (char *)&id[ATA_ID_PROD]);
 224                 return blacklist;
 225         }
 226         return 0;
 227 }
 228 EXPORT_SYMBOL(__ide_dma_bad_drive);
 229
 230 static const u8 xfer_mode_bases[] = {
 231         XFER_UDMA_0,
 232         XFER_MW_DMA_0,
 233         XFER_SW_DMA_0,
 234 };
 235
 236 static unsigned int ide_get_mode_mask(ide_drive_t *drive, u8 base, u8 req_mode)
 237 {
 238         u16 *id = drive->id;
 239         ide_hwif_t *hwif = drive->hwif;
 240         const struct ide_port_ops *port_ops = hwif->port_ops;
 241         unsigned int mask = 0;
 242
 243         switch (base) {
 244         case XFER_UDMA_0:
 245                 if ((id[ATA_ID_FIELD_VALID] & 4) == 0)
 246                         break;
 247
 248                 if (port_ops && port_ops->udma_filter)
 249                         mask = port_ops->udma_filter(drive);
 250                 else
 251                         mask = hwif->ultra_mask;
 252                 mask &= id[ATA_ID_UDMA_MODES];
 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                 if ((id[ATA_ID_FIELD_VALID] & 2) == 0)
 264                         break;
 265                 if (port_ops && port_ops->mdma_filter)
 266                         mask = port_ops->mdma_filter(drive);
 267                 else
 268                         mask = hwif->mwdma_mask;
 269                 mask &= id[ATA_ID_MWDMA_MODES];
 270                 break;
 271         case XFER_SW_DMA_0:
 272                 if (id[ATA_ID_FIELD_VALID] & 2) {
 273                         mask = id[ATA_ID_SWDMA_MODES] & hwif->swdma_mask;
 274                 } else if (id[ATA_ID_OLD_DMA_MODES] >> 8) {
 275                         u8 mode = id[ATA_ID_OLD_DMA_MODES] >> 8;
 276
 277                         /*
 278                          * if the mode is valid convert it to the mask
 279                          * (the maximum allowed mode is XFER_SW_DMA_2)
 280                          */
 281                         if (mode <= 2)
 282                                 mask = ((2 << mode) - 1) & hwif->swdma_mask;
 283                 }
 284                 break;
 285         default:
 286                 BUG();
 287                 break;
 288         }
 289
 290         return mask;
 291 }
 292
 293 /**
 294  *      ide_find_dma_mode       -       compute DMA speed
 295  *      @drive: IDE device
 296  *      @req_mode: requested mode
 297  *
 298  *      Checks the drive/host capabilities and finds the speed to use for
 299  *      the DMA transfer.  The speed is then limited by the requested mode.
 300  *
 301  *      Returns 0 if the drive/host combination is incapable of DMA transfers
 302  *      or if the requested mode is not a DMA mode.
 303  */
 304
 305 u8 ide_find_dma_mode(ide_drive_t *drive, u8 req_mode)
 306 {
 307         ide_hwif_t *hwif = drive->hwif;
 308         unsigned int mask;
 309         int x, i;
 310         u8 mode = 0;
 311
 312         if (drive->media != ide_disk) {
 313                 if (hwif->host_flags & IDE_HFLAG_NO_ATAPI_DMA)
 314                         return 0;
 315         }
 316
 317         for (i = 0; i < ARRAY_SIZE(xfer_mode_bases); i++) {
 318                 if (req_mode < xfer_mode_bases[i])
 319                         continue;
 320                 mask = ide_get_mode_mask(drive, xfer_mode_bases[i], req_mode);
 321                 x = fls(mask) - 1;
 322                 if (x >= 0) {
 323                         mode = xfer_mode_bases[i] + x;
 324                         break;
 325                 }
 326         }
 327
 328         if (hwif->chipset == ide_acorn && mode == 0) {
 329                 /*
 330                  * is this correct?
 331                  */
 332                 if (ide_dma_good_drive(drive) &&
 333                     drive->id[ATA_ID_EIDE_DMA_TIME] < 150)
 334                         mode = XFER_MW_DMA_1;
 335         }
 336
 337         mode = min(mode, req_mode);
 338
 339         printk(KERN_INFO "%s: %s mode selected\n", drive->name,
 340                           mode ? ide_xfer_verbose(mode) : "no DMA");
 341
 342         return mode;
 343 }
 344 EXPORT_SYMBOL_GPL(ide_find_dma_mode);
 345
 346 static int ide_tune_dma(ide_drive_t *drive)
 347 {
 348         ide_hwif_t *hwif = drive->hwif;
 349         u8 speed;
 350
 351         if (ata_id_has_dma(drive->id) == 0 ||
 352             (drive->dev_flags & IDE_DFLAG_NODMA))
 353                 return 0;
 354
 355         /* consult the list of known "bad" drives */
 356         if (__ide_dma_bad_drive(drive))
 357                 return 0;
 358
 359         if (ide_id_dma_bug(drive))
 360                 return 0;
 361
 362         if (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA)
 363                 return config_drive_for_dma(drive);
 364
 365         speed = ide_max_dma_mode(drive);
 366
 367         if (!speed)
 368                 return 0;
 369
 370         if (ide_set_dma_mode(drive, speed))
 371                 return 0;
 372
 373         return 1;
 374 }
 375
 376 static int ide_dma_check(ide_drive_t *drive)
 377 {
 378         ide_hwif_t *hwif = drive->hwif;
 379
 380         if (ide_tune_dma(drive))
 381                 return 0;
 382
 383         /* TODO: always do PIO fallback */
 384         if (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA)
 385                 return -1;
 386
 387         ide_set_max_pio(drive);
 388
 389         return -1;
 390 }
 391
 392 int ide_id_dma_bug(ide_drive_t *drive)
 393 {
 394         u16 *id = drive->id;
 395
 396         if (id[ATA_ID_FIELD_VALID] & 4) {
 397                 if ((id[ATA_ID_UDMA_MODES] >> 8) &&
 398                     (id[ATA_ID_MWDMA_MODES] >> 8))
 399                         goto err_out;
 400         } else if (id[ATA_ID_FIELD_VALID] & 2) {
 401                 if ((id[ATA_ID_MWDMA_MODES] >> 8) &&
 402                     (id[ATA_ID_SWDMA_MODES] >> 8))
 403                         goto err_out;
 404         }
 405         return 0;
 406 err_out:
 407         printk(KERN_ERR "%s: bad DMA info in identify block\n", drive->name);
 408         return 1;
 409 }
 410
 411 int ide_set_dma(ide_drive_t *drive)
 412 {
 413         int rc;
 414
 415         /*
 416          * Force DMAing for the beginning of the check.
 417          * Some chipsets appear to do interesting
 418          * things, if not checked and cleared.
 419          *   PARANOIA!!!
 420          */
 421         ide_dma_off_quietly(drive);
 422
 423         rc = ide_dma_check(drive);
 424         if (rc)
 425                 return rc;
 426
 427         ide_dma_on(drive);
 428
 429         return 0;
 430 }
 431
 432 void ide_check_dma_crc(ide_drive_t *drive)
 433 {
 434         u8 mode;
 435
 436         ide_dma_off_quietly(drive);
 437         drive->crc_count = 0;
 438         mode = drive->current_speed;
 439         /*
 440          * Don't try non Ultra-DMA modes without iCRC's.  Force the
 441          * device to PIO and make the user enable SWDMA/MWDMA modes.
 442          */
 443         if (mode > XFER_UDMA_0 && mode <= XFER_UDMA_7)
 444                 mode--;
 445         else
 446                 mode = XFER_PIO_4;
 447         ide_set_xfer_rate(drive, mode);
 448         if (drive->current_speed >= XFER_SW_DMA_0)
 449                 ide_dma_on(drive);
 450 }
 451
 452 void ide_dma_lost_irq(ide_drive_t *drive)
 453 {
 454         printk(KERN_ERR "%s: DMA interrupt recovery\n", drive->name);
 455 }
 456 EXPORT_SYMBOL_GPL(ide_dma_lost_irq);
 457
 458 void ide_dma_timeout(ide_drive_t *drive)
 459 {
 460         ide_hwif_t *hwif = drive->hwif;
 461
 462         printk(KERN_ERR "%s: timeout waiting for DMA\n", drive->name);
 463
 464         if (hwif->dma_ops->dma_test_irq(drive))
 465                 return;
 466
 467         ide_dump_status(drive, "DMA timeout", hwif->tp_ops->read_status(hwif));
 468
 469         hwif->dma_ops->dma_end(drive);
 470 }
 471 EXPORT_SYMBOL_GPL(ide_dma_timeout);
 472
 473 void ide_release_dma_engine(ide_hwif_t *hwif)
 474 {
 475         if (hwif->dmatable_cpu) {
 476                 int prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
 477
 478                 dma_free_coherent(hwif->dev, prd_size,
 479                                   hwif->dmatable_cpu, hwif->dmatable_dma);
 480                 hwif->dmatable_cpu = NULL;
 481         }
 482 }
 483 EXPORT_SYMBOL_GPL(ide_release_dma_engine);
 484
 485 int ide_allocate_dma_engine(ide_hwif_t *hwif)
 486 {
 487         int prd_size;
 488
 489         if (hwif->prd_max_nents == 0)
 490                 hwif->prd_max_nents = PRD_ENTRIES;
 491         if (hwif->prd_ent_size == 0)
 492                 hwif->prd_ent_size = PRD_BYTES;
 493
 494         prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
 495
 496         hwif->dmatable_cpu = dma_alloc_coherent(hwif->dev, prd_size,
 497                                                 &hwif->dmatable_dma,
 498                                                 GFP_ATOMIC);
 499         if (hwif->dmatable_cpu == NULL) {
 500                 printk(KERN_ERR "%s: unable to allocate PRD table\n",
 501                         hwif->name);
 502                 return -ENOMEM;
 503         }
 504
 505         return 0;
 506 }
 507 EXPORT_SYMBOL_GPL(ide_allocate_dma_engine);