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/export.h>
  35 #include <linux/ide.h>
  36 #include <linux/scatterlist.h>
  37 #include <linux/dma-mapping.h>
  38
  39 static const struct drive_list_entry drive_whitelist[] = {
  40         { "Micropolis 2112A"    ,       NULL            },
  41         { "CONNER CTMA 4000"    ,       NULL            },
  42         { "CONNER CTT8000-A"    ,       NULL            },
  43         { "ST34342A"            ,       NULL            },
  44         { NULL                  ,       NULL            }
  45 };
  46
  47 static const struct drive_list_entry drive_blacklist[] = {
  48         { "WDC AC11000H"        ,       NULL            },
  49         { "WDC AC22100H"        ,       NULL            },
  50         { "WDC AC32500H"        ,       NULL            },
  51         { "WDC AC33100H"        ,       NULL            },
  52         { "WDC AC31600H"        ,       NULL            },
  53         { "WDC AC32100H"        ,       "24.09P07"      },
  54         { "WDC AC23200L"        ,       "21.10N21"      },
  55         { "Compaq CRD-8241B"    ,       NULL            },
  56         { "CRD-8400B"           ,       NULL            },
  57         { "CRD-8480B",                  NULL            },
  58         { "CRD-8482B",                  NULL            },
  59         { "CRD-84"              ,       NULL            },
  60         { "SanDisk SDP3B"       ,       NULL            },
  61         { "SanDisk SDP3B-64"    ,       NULL            },
  62         { "SANYO CD-ROM CRD"    ,       NULL            },
  63         { "HITACHI CDR-8"       ,       NULL            },
  64         { "HITACHI CDR-8335"    ,       NULL            },
  65         { "HITACHI CDR-8435"    ,       NULL            },
  66         { "Toshiba CD-ROM XM-6202B"     ,       NULL            },
  67         { "TOSHIBA CD-ROM XM-1702BC",   NULL            },
  68         { "CD-532E-A"           ,       NULL            },
  69         { "E-IDE CD-ROM CR-840",        NULL            },
  70         { "CD-ROM Drive/F5A",   NULL            },
  71         { "WPI CDD-820",                NULL            },
  72         { "SAMSUNG CD-ROM SC-148C",     NULL            },
  73         { "SAMSUNG CD-ROM SC",  NULL            },
  74         { "ATAPI CD-ROM DRIVE 40X MAXIMUM",     NULL            },
  75         { "_NEC DV5800A",               NULL            },
  76         { "SAMSUNG CD-ROM SN-124",      "N001" },
  77         { "Seagate STT20000A",          NULL  },
  78         { "CD-ROM CDR_U200",            "1.09" },
  79         { NULL                  ,       NULL            }
  80
  81 };
  82
  83 /**
  84  *      ide_dma_intr    -       IDE DMA interrupt handler
  85  *      @drive: the drive the interrupt is for
  86  *
  87  *      Handle an interrupt completing a read/write DMA transfer on an
  88  *      IDE device
  89  */
  90
  91 ide_startstop_t ide_dma_intr(ide_drive_t *drive)
  92 {
  93         ide_hwif_t *hwif = drive->hwif;
  94         struct ide_cmd *cmd = &hwif->cmd;
  95         u8 stat = 0, dma_stat = 0;
  96
  97         drive->waiting_for_dma = 0;
  98         dma_stat = hwif->dma_ops->dma_end(drive);
  99         ide_dma_unmap_sg(drive, cmd);
 100         stat = hwif->tp_ops->read_status(hwif);
 101
 102         if (OK_STAT(stat, DRIVE_READY, drive->bad_wstat | ATA_DRQ)) {
 103                 if (!dma_stat) {
 104                         if ((cmd->tf_flags & IDE_TFLAG_FS) == 0)
 105                                 ide_finish_cmd(drive, cmd, stat);
 106                         else
 107                                 ide_complete_rq(drive, 0,
 108                                                 blk_rq_sectors(cmd->rq) << 9);
 109                         return ide_stopped;
 110                 }
 111                 printk(KERN_ERR "%s: %s: bad DMA status (0x%02x)\n",
 112                         drive->name, __func__, dma_stat);
 113         }
 114         return ide_error(drive, "dma_intr", stat);
 115 }
 116
 117 int ide_dma_good_drive(ide_drive_t *drive)
 118 {
 119         return ide_in_drive_list(drive->id, drive_whitelist);
 120 }
 121
 122 /**
 123  *      ide_dma_map_sg  -       map IDE scatter gather for DMA I/O
 124  *      @drive: the drive to map the DMA table for
 125  *      @cmd: command
 126  *
 127  *      Perform the DMA mapping magic necessary to access the source or
 128  *      target buffers of a request via DMA.  The lower layers of the
 129  *      kernel provide the necessary cache management so that we can
 130  *      operate in a portable fashion.
 131  */
 132
 133 static int ide_dma_map_sg(ide_drive_t *drive, struct ide_cmd *cmd)
 134 {
 135         ide_hwif_t *hwif = drive->hwif;
 136         struct scatterlist *sg = hwif->sg_table;
 137         int i;
 138
 139         if (cmd->tf_flags & IDE_TFLAG_WRITE)
 140                 cmd->sg_dma_direction = DMA_TO_DEVICE;
 141         else
 142                 cmd->sg_dma_direction = DMA_FROM_DEVICE;
 143
 144         i = dma_map_sg(hwif->dev, sg, cmd->sg_nents, cmd->sg_dma_direction);
 145         if (i) {
 146                 cmd->orig_sg_nents = cmd->sg_nents;
 147                 cmd->sg_nents = i;
 148         }
 149
 150         return i;
 151 }
 152
 153 /**
 154  *      ide_dma_unmap_sg        -       clean up DMA mapping
 155  *      @drive: The drive to unmap
 156  *
 157  *      Teardown mappings after DMA has completed. This must be called
 158  *      after the completion of each use of ide_build_dmatable and before
 159  *      the next use of ide_build_dmatable. Failure to do so will cause
 160  *      an oops as only one mapping can be live for each target at a given
 161  *      time.
 162  */
 163
 164 void ide_dma_unmap_sg(ide_drive_t *drive, struct ide_cmd *cmd)
 165 {
 166         ide_hwif_t *hwif = drive->hwif;
 167
 168         dma_unmap_sg(hwif->dev, hwif->sg_table, cmd->orig_sg_nents,
 169                      cmd->sg_dma_direction);
 170 }
 171 EXPORT_SYMBOL_GPL(ide_dma_unmap_sg);
 172
 173 /**
 174  *      ide_dma_off_quietly     -       Generic DMA kill
 175  *      @drive: drive to control
 176  *
 177  *      Turn off the current DMA on this IDE controller.
 178  */
 179
 180 void ide_dma_off_quietly(ide_drive_t *drive)
 181 {
 182         drive->dev_flags &= ~IDE_DFLAG_USING_DMA;
 183         ide_toggle_bounce(drive, 0);
 184
 185         drive->hwif->dma_ops->dma_host_set(drive, 0);
 186 }
 187 EXPORT_SYMBOL(ide_dma_off_quietly);
 188
 189 /**
 190  *      ide_dma_off     -       disable DMA on a device
 191  *      @drive: drive to disable DMA on
 192  *
 193  *      Disable IDE DMA for a device on this IDE controller.
 194  *      Inform the user that DMA has been disabled.
 195  */
 196
 197 void ide_dma_off(ide_drive_t *drive)
 198 {
 199         printk(KERN_INFO "%s: DMA disabled\n", drive->name);
 200         ide_dma_off_quietly(drive);
 201 }
 202 EXPORT_SYMBOL(ide_dma_off);
 203
 204 /**
 205  *      ide_dma_on              -       Enable DMA on a device
 206  *      @drive: drive to enable DMA on
 207  *
 208  *      Enable IDE DMA for a device on this IDE controller.
 209  */
 210
 211 void ide_dma_on(ide_drive_t *drive)
 212 {
 213         drive->dev_flags |= IDE_DFLAG_USING_DMA;
 214         ide_toggle_bounce(drive, 1);
 215
 216         drive->hwif->dma_ops->dma_host_set(drive, 1);
 217 }
 218
 219 int __ide_dma_bad_drive(ide_drive_t *drive)
 220 {
 221         u16 *id = drive->id;
 222
 223         int blacklist = ide_in_drive_list(id, drive_blacklist);
 224         if (blacklist) {
 225                 printk(KERN_WARNING "%s: Disabling (U)DMA for %s (blacklisted)\n",
 226                                     drive->name, (char *)&id[ATA_ID_PROD]);
 227                 return blacklist;
 228         }
 229         return 0;
 230 }
 231 EXPORT_SYMBOL(__ide_dma_bad_drive);
 232
 233 static const u8 xfer_mode_bases[] = {
 234         XFER_UDMA_0,
 235         XFER_MW_DMA_0,
 236         XFER_SW_DMA_0,
 237 };
 238
 239 static unsigned int ide_get_mode_mask(ide_drive_t *drive, u8 base, u8 req_mode)
 240 {
 241         u16 *id = drive->id;
 242         ide_hwif_t *hwif = drive->hwif;
 243         const struct ide_port_ops *port_ops = hwif->port_ops;
 244         unsigned int mask = 0;
 245
 246         switch (base) {
 247         case XFER_UDMA_0:
 248                 if ((id[ATA_ID_FIELD_VALID] & 4) == 0)
 249                         break;
 250                 mask = id[ATA_ID_UDMA_MODES];
 251                 if (port_ops && port_ops->udma_filter)
 252                         mask &= port_ops->udma_filter(drive);
 253                 else
 254                         mask &= hwif->ultra_mask;
 255
 256                 /*
 257                  * avoid false cable warning from eighty_ninty_three()
 258                  */
 259                 if (req_mode > XFER_UDMA_2) {
 260                         if ((mask & 0x78) && (eighty_ninty_three(drive) == 0))
 261                                 mask &= 0x07;
 262                 }
 263                 break;
 264         case XFER_MW_DMA_0:
 265                 mask = id[ATA_ID_MWDMA_MODES];
 266
 267                 /* Also look for the CF specific MWDMA modes... */
 268                 if (ata_id_is_cfa(id) && (id[ATA_ID_CFA_MODES] & 0x38)) {
 269                         u8 mode = ((id[ATA_ID_CFA_MODES] & 0x38) >> 3) - 1;
 270
 271                         mask |= ((2 << mode) - 1) << 3;
 272                 }
 273
 274                 if (port_ops && port_ops->mdma_filter)
 275                         mask &= port_ops->mdma_filter(drive);
 276                 else
 277                         mask &= hwif->mwdma_mask;
 278                 break;
 279         case XFER_SW_DMA_0:
 280                 mask = id[ATA_ID_SWDMA_MODES];
 281                 if (!(mask & ATA_SWDMA2) && (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;
 290                 }
 291                 mask &= hwif->swdma_mask;
 292                 break;
 293         default:
 294                 BUG();
 295                 break;
 296         }
 297
 298         return mask;
 299 }
 300
 301 /**
 302  *      ide_find_dma_mode       -       compute DMA speed
 303  *      @drive: IDE device
 304  *      @req_mode: requested mode
 305  *
 306  *      Checks the drive/host capabilities and finds the speed to use for
 307  *      the DMA transfer.  The speed is then limited by the requested mode.
 308  *
 309  *      Returns 0 if the drive/host combination is incapable of DMA transfers
 310  *      or if the requested mode is not a DMA mode.
 311  */
 312
 313 u8 ide_find_dma_mode(ide_drive_t *drive, u8 req_mode)
 314 {
 315         ide_hwif_t *hwif = drive->hwif;
 316         unsigned int mask;
 317         int x, i;
 318         u8 mode = 0;
 319
 320         if (drive->media != ide_disk) {
 321                 if (hwif->host_flags & IDE_HFLAG_NO_ATAPI_DMA)
 322                         return 0;
 323         }
 324
 325         for (i = 0; i < ARRAY_SIZE(xfer_mode_bases); i++) {
 326                 if (req_mode < xfer_mode_bases[i])
 327                         continue;
 328                 mask = ide_get_mode_mask(drive, xfer_mode_bases[i], req_mode);
 329                 x = fls(mask) - 1;
 330                 if (x >= 0) {
 331                         mode = xfer_mode_bases[i] + x;
 332                         break;
 333                 }
 334         }
 335
 336         if (hwif->chipset == ide_acorn && mode == 0) {
 337                 /*
 338                  * is this correct?
 339                  */
 340                 if (ide_dma_good_drive(drive) &&
 341                     drive->id[ATA_ID_EIDE_DMA_TIME] < 150)
 342                         mode = XFER_MW_DMA_1;
 343         }
 344
 345         mode = min(mode, req_mode);
 346
 347         printk(KERN_INFO "%s: %s mode selected\n", drive->name,
 348                           mode ? ide_xfer_verbose(mode) : "no DMA");
 349
 350         return mode;
 351 }
 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 (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA)
 367                 return config_drive_for_dma(drive);
 368
 369         speed = ide_max_dma_mode(drive);
 370
 371         if (!speed)
 372                 return 0;
 373
 374         if (ide_set_dma_mode(drive, speed))
 375                 return 0;
 376
 377         return 1;
 378 }
 379
 380 static int ide_dma_check(ide_drive_t *drive)
 381 {
 382         ide_hwif_t *hwif = drive->hwif;
 383
 384         if (ide_tune_dma(drive))
 385                 return 0;
 386
 387         /* TODO: always do PIO fallback */
 388         if (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA)
 389                 return -1;
 390
 391         ide_set_max_pio(drive);
 392
 393         return -1;
 394 }
 395
 396 int ide_set_dma(ide_drive_t *drive)
 397 {
 398         int rc;
 399
 400         /*
 401          * Force DMAing for the beginning of the check.
 402          * Some chipsets appear to do interesting
 403          * things, if not checked and cleared.
 404          *   PARANOIA!!!
 405          */
 406         ide_dma_off_quietly(drive);
 407
 408         rc = ide_dma_check(drive);
 409         if (rc)
 410                 return rc;
 411
 412         ide_dma_on(drive);
 413
 414         return 0;
 415 }
 416
 417 void ide_check_dma_crc(ide_drive_t *drive)
 418 {
 419         u8 mode;
 420
 421         ide_dma_off_quietly(drive);
 422         drive->crc_count = 0;
 423         mode = drive->current_speed;
 424         /*
 425          * Don't try non Ultra-DMA modes without iCRC's.  Force the
 426          * device to PIO and make the user enable SWDMA/MWDMA modes.
 427          */
 428         if (mode > XFER_UDMA_0 && mode <= XFER_UDMA_7)
 429                 mode--;
 430         else
 431                 mode = XFER_PIO_4;
 432         ide_set_xfer_rate(drive, mode);
 433         if (drive->current_speed >= XFER_SW_DMA_0)
 434                 ide_dma_on(drive);
 435 }
 436
 437 void ide_dma_lost_irq(ide_drive_t *drive)
 438 {
 439         printk(KERN_ERR "%s: DMA interrupt recovery\n", drive->name);
 440 }
 441 EXPORT_SYMBOL_GPL(ide_dma_lost_irq);
 442
 443 /*
 444  * un-busy the port etc, and clear any pending DMA status. we want to
 445  * retry the current request in pio mode instead of risking tossing it
 446  * all away
 447  */
 448 ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
 449 {
 450         ide_hwif_t *hwif = drive->hwif;
 451         const struct ide_dma_ops *dma_ops = hwif->dma_ops;
 452         struct ide_cmd *cmd = &hwif->cmd;
 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          * make sure request is sane
 491          */
 492         if (hwif->rq)
 493                 hwif->rq->errors = 0;
 494         return ret;
 495 }
 496
 497 void ide_release_dma_engine(ide_hwif_t *hwif)
 498 {
 499         if (hwif->dmatable_cpu) {
 500                 int prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
 501
 502                 dma_free_coherent(hwif->dev, prd_size,
 503                                   hwif->dmatable_cpu, hwif->dmatable_dma);
 504                 hwif->dmatable_cpu = NULL;
 505         }
 506 }
 507 EXPORT_SYMBOL_GPL(ide_release_dma_engine);
 508
 509 int ide_allocate_dma_engine(ide_hwif_t *hwif)
 510 {
 511         int prd_size;
 512
 513         if (hwif->prd_max_nents == 0)
 514                 hwif->prd_max_nents = PRD_ENTRIES;
 515         if (hwif->prd_ent_size == 0)
 516                 hwif->prd_ent_size = PRD_BYTES;
 517
 518         prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
 519
 520         hwif->dmatable_cpu = dma_alloc_coherent(hwif->dev, prd_size,
 521                                                 &hwif->dmatable_dma,
 522                                                 GFP_ATOMIC);
 523         if (hwif->dmatable_cpu == NULL) {
 524                 printk(KERN_ERR "%s: unable to allocate PRD table\n",
 525                         hwif->name);
 526                 return -ENOMEM;
 527         }
 528
 529         return 0;
 530 }
 531 EXPORT_SYMBOL_GPL(ide_allocate_dma_engine);
 532
 533 int ide_dma_prepare(ide_drive_t *drive, struct ide_cmd *cmd)
 534 {
 535         const struct ide_dma_ops *dma_ops = drive->hwif->dma_ops;
 536
 537         if ((drive->dev_flags & IDE_DFLAG_USING_DMA) == 0 ||
 538             (dma_ops->dma_check && dma_ops->dma_check(drive, cmd)))
 539                 goto out;
 540         ide_map_sg(drive, cmd);
 541         if (ide_dma_map_sg(drive, cmd) == 0)
 542                 goto out_map;
 543         if (dma_ops->dma_setup(drive, cmd))
 544                 goto out_dma_unmap;
 545         drive->waiting_for_dma = 1;
 546         return 0;
 547 out_dma_unmap:
 548         ide_dma_unmap_sg(drive, cmd);
 549 out_map:
 550         ide_map_sg(drive, cmd);
 551 out:
 552         return 1;
 553 }