git.oblomov.eu Git - linux-2.6/blob - drivers/ide/ide-acpi.c

   1 /*
   2  * Provides ACPI support for IDE drives.
   3  *
   4  * Copyright (C) 2005 Intel Corp.
   5  * Copyright (C) 2005 Randy Dunlap
   6  * Copyright (C) 2006 SUSE Linux Products GmbH
   7  * Copyright (C) 2006 Hannes Reinecke
   8  */
   9
  10 #include <linux/ata.h>
  11 #include <linux/delay.h>
  12 #include <linux/device.h>
  13 #include <linux/errno.h>
  14 #include <linux/kernel.h>
  15 #include <acpi/acpi.h>
  16 #include <linux/ide.h>
  17 #include <linux/pci.h>
  18 #include <linux/dmi.h>
  19
  20 #include <acpi/acpi_bus.h>
  21
  22 #define REGS_PER_GTF            7
  23
  24 struct GTM_buffer {
  25         u32     PIO_speed0;
  26         u32     DMA_speed0;
  27         u32     PIO_speed1;
  28         u32     DMA_speed1;
  29         u32     GTM_flags;
  30 };
  31
  32 struct ide_acpi_drive_link {
  33         acpi_handle      obj_handle;
  34         u8               idbuff[512];
  35 };
  36
  37 struct ide_acpi_hwif_link {
  38         ide_hwif_t                      *hwif;
  39         acpi_handle                      obj_handle;
  40         struct GTM_buffer                gtm;
  41         struct ide_acpi_drive_link       master;
  42         struct ide_acpi_drive_link       slave;
  43 };
  44
  45 #undef DEBUGGING
  46 /* note: adds function name and KERN_DEBUG */
  47 #ifdef DEBUGGING
  48 #define DEBPRINT(fmt, args...)  \
  49                 printk(KERN_DEBUG "%s: " fmt, __func__, ## args)
  50 #else
  51 #define DEBPRINT(fmt, args...)  do {} while (0)
  52 #endif  /* DEBUGGING */
  53
  54 static int ide_noacpi;
  55 module_param_named(noacpi, ide_noacpi, bool, 0);
  56 MODULE_PARM_DESC(noacpi, "disable IDE ACPI support");
  57
  58 static int ide_acpigtf;
  59 module_param_named(acpigtf, ide_acpigtf, bool, 0);
  60 MODULE_PARM_DESC(acpigtf, "enable IDE ACPI _GTF support");
  61
  62 static int ide_acpionboot;
  63 module_param_named(acpionboot, ide_acpionboot, bool, 0);
  64 MODULE_PARM_DESC(acpionboot, "call IDE ACPI methods on boot");
  65
  66 static bool ide_noacpi_psx;
  67 static int no_acpi_psx(const struct dmi_system_id *id)
  68 {
  69         ide_noacpi_psx = true;
  70         printk(KERN_NOTICE"%s detected - disable ACPI _PSx.\n", id->ident);
  71         return 0;
  72 }
  73
  74 static const struct dmi_system_id ide_acpi_dmi_table[] = {
  75         /* Bug 9673. */
  76         /* We should check if this is because ACPI NVS isn't save/restored. */
  77         {
  78                 .callback = no_acpi_psx,
  79                 .ident    = "HP nx9005",
  80                 .matches  = {
  81                         DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies Ltd."),
  82                         DMI_MATCH(DMI_BIOS_VERSION, "KAM1.60")
  83                 },
  84         },
  85
  86         { }     /* terminate list */
  87 };
  88
  89 int ide_acpi_init(void)
  90 {
  91         dmi_check_system(ide_acpi_dmi_table);
  92         return 0;
  93 }
  94
  95 /**
  96  * ide_get_dev_handle - finds acpi_handle and PCI device.function
  97  * @dev: device to locate
  98  * @handle: returned acpi_handle for @dev
  99  * @pcidevfn: return PCI device.func for @dev
 100  *
 101  * Returns the ACPI object handle to the corresponding PCI device.
 102  *
 103  * Returns 0 on success, <0 on error.
 104  */
 105 static int ide_get_dev_handle(struct device *dev, acpi_handle *handle,
 106                                acpi_integer *pcidevfn)
 107 {
 108         struct pci_dev *pdev = to_pci_dev(dev);
 109         unsigned int bus, devnum, func;
 110         acpi_integer addr;
 111         acpi_handle dev_handle;
 112         struct acpi_buffer buffer = {.length = ACPI_ALLOCATE_BUFFER,
 113                                         .pointer = NULL};
 114         acpi_status status;
 115         struct acpi_device_info *dinfo = NULL;
 116         int ret = -ENODEV;
 117
 118         bus = pdev->bus->number;
 119         devnum = PCI_SLOT(pdev->devfn);
 120         func = PCI_FUNC(pdev->devfn);
 121         /* ACPI _ADR encoding for PCI bus: */
 122         addr = (acpi_integer)(devnum << 16 | func);
 123
 124         DEBPRINT("ENTER: pci %02x:%02x.%01x\n", bus, devnum, func);
 125
 126         dev_handle = DEVICE_ACPI_HANDLE(dev);
 127         if (!dev_handle) {
 128                 DEBPRINT("no acpi handle for device\n");
 129                 goto err;
 130         }
 131
 132         status = acpi_get_object_info(dev_handle, &buffer);
 133         if (ACPI_FAILURE(status)) {
 134                 DEBPRINT("get_object_info for device failed\n");
 135                 goto err;
 136         }
 137         dinfo = buffer.pointer;
 138         if (dinfo && (dinfo->valid & ACPI_VALID_ADR) &&
 139             dinfo->address == addr) {
 140                 *pcidevfn = addr;
 141                 *handle = dev_handle;
 142         } else {
 143                 DEBPRINT("get_object_info for device has wrong "
 144                         " address: %llu, should be %u\n",
 145                         dinfo ? (unsigned long long)dinfo->address : -1ULL,
 146                         (unsigned int)addr);
 147                 goto err;
 148         }
 149
 150         DEBPRINT("for dev=0x%x.%x, addr=0x%llx, *handle=0x%p\n",
 151                  devnum, func, (unsigned long long)addr, *handle);
 152         ret = 0;
 153 err:
 154         kfree(dinfo);
 155         return ret;
 156 }
 157
 158 /**
 159  * ide_acpi_hwif_get_handle - Get ACPI object handle for a given hwif
 160  * @hwif: device to locate
 161  *
 162  * Retrieves the object handle for a given hwif.
 163  *
 164  * Returns handle on success, 0 on error.
 165  */
 166 static acpi_handle ide_acpi_hwif_get_handle(ide_hwif_t *hwif)
 167 {
 168         struct device           *dev = hwif->gendev.parent;
 169         acpi_handle             uninitialized_var(dev_handle);
 170         acpi_integer            pcidevfn;
 171         acpi_handle             chan_handle;
 172         int                     err;
 173
 174         DEBPRINT("ENTER: device %s\n", hwif->name);
 175
 176         if (!dev) {
 177                 DEBPRINT("no PCI device for %s\n", hwif->name);
 178                 return NULL;
 179         }
 180
 181         err = ide_get_dev_handle(dev, &dev_handle, &pcidevfn);
 182         if (err < 0) {
 183                 DEBPRINT("ide_get_dev_handle failed (%d)\n", err);
 184                 return NULL;
 185         }
 186
 187         /* get child objects of dev_handle == channel objects,
 188          * + _their_ children == drive objects */
 189         /* channel is hwif->channel */
 190         chan_handle = acpi_get_child(dev_handle, hwif->channel);
 191         DEBPRINT("chan adr=%d: handle=0x%p\n",
 192                  hwif->channel, chan_handle);
 193
 194         return chan_handle;
 195 }
 196
 197 /**
 198  * do_drive_get_GTF - get the drive bootup default taskfile settings
 199  * @drive: the drive for which the taskfile settings should be retrieved
 200  * @gtf_length: number of bytes of _GTF data returned at @gtf_address
 201  * @gtf_address: buffer containing _GTF taskfile arrays
 202  *
 203  * The _GTF method has no input parameters.
 204  * It returns a variable number of register set values (registers
 205  * hex 1F1..1F7, taskfiles).
 206  * The <variable number> is not known in advance, so have ACPI-CA
 207  * allocate the buffer as needed and return it, then free it later.
 208  *
 209  * The returned @gtf_length and @gtf_address are only valid if the
 210  * function return value is 0.
 211  */
 212 static int do_drive_get_GTF(ide_drive_t *drive,
 213                      unsigned int *gtf_length, unsigned long *gtf_address,
 214                      unsigned long *obj_loc)
 215 {
 216         acpi_status                     status;
 217         struct acpi_buffer              output;
 218         union acpi_object               *out_obj;
 219         int                             err = -ENODEV;
 220
 221         *gtf_length = 0;
 222         *gtf_address = 0UL;
 223         *obj_loc = 0UL;
 224
 225         if (!drive->acpidata->obj_handle) {
 226                 DEBPRINT("No ACPI object found for %s\n", drive->name);
 227                 goto out;
 228         }
 229
 230         /* Setting up output buffer */
 231         output.length = ACPI_ALLOCATE_BUFFER;
 232         output.pointer = NULL;  /* ACPI-CA sets this; save/free it later */
 233
 234         /* _GTF has no input parameters */
 235         err = -EIO;
 236         status = acpi_evaluate_object(drive->acpidata->obj_handle, "_GTF",
 237                                       NULL, &output);
 238         if (ACPI_FAILURE(status)) {
 239                 printk(KERN_DEBUG
 240                        "%s: Run _GTF error: status = 0x%x\n",
 241                        __func__, status);
 242                 goto out;
 243         }
 244
 245         if (!output.length || !output.pointer) {
 246                 DEBPRINT("Run _GTF: "
 247                        "length or ptr is NULL (0x%llx, 0x%p)\n",
 248                        (unsigned long long)output.length,
 249                        output.pointer);
 250                 goto out;
 251         }
 252
 253         out_obj = output.pointer;
 254         if (out_obj->type != ACPI_TYPE_BUFFER) {
 255                 DEBPRINT("Run _GTF: error: "
 256                        "expected object type of ACPI_TYPE_BUFFER, "
 257                        "got 0x%x\n", out_obj->type);
 258                 err = -ENOENT;
 259                 kfree(output.pointer);
 260                 goto out;
 261         }
 262
 263         if (!out_obj->buffer.length || !out_obj->buffer.pointer ||
 264             out_obj->buffer.length % REGS_PER_GTF) {
 265                 printk(KERN_ERR
 266                        "%s: unexpected GTF length (%d) or addr (0x%p)\n",
 267                        __func__, out_obj->buffer.length,
 268                        out_obj->buffer.pointer);
 269                 err = -ENOENT;
 270                 kfree(output.pointer);
 271                 goto out;
 272         }
 273
 274         *gtf_length = out_obj->buffer.length;
 275         *gtf_address = (unsigned long)out_obj->buffer.pointer;
 276         *obj_loc = (unsigned long)out_obj;
 277         DEBPRINT("returning gtf_length=%d, gtf_address=0x%lx, obj_loc=0x%lx\n",
 278                  *gtf_length, *gtf_address, *obj_loc);
 279         err = 0;
 280 out:
 281         return err;
 282 }
 283
 284 /**
 285  * do_drive_set_taskfiles - write the drive taskfile settings from _GTF
 286  * @drive: the drive to which the taskfile command should be sent
 287  * @gtf_length: total number of bytes of _GTF taskfiles
 288  * @gtf_address: location of _GTF taskfile arrays
 289  *
 290  * Write {gtf_address, length gtf_length} in groups of
 291  * REGS_PER_GTF bytes.
 292  */
 293 static int do_drive_set_taskfiles(ide_drive_t *drive,
 294                                   unsigned int gtf_length,
 295                                   unsigned long gtf_address)
 296 {
 297         int                     rc = 0, err;
 298         int                     gtf_count = gtf_length / REGS_PER_GTF;
 299         int                     ix;
 300
 301         DEBPRINT("total GTF bytes=%u (0x%x), gtf_count=%d, addr=0x%lx\n",
 302                  gtf_length, gtf_length, gtf_count, gtf_address);
 303
 304         /* send all taskfile registers (0x1f1-0x1f7) *in*that*order* */
 305         for (ix = 0; ix < gtf_count; ix++) {
 306                 u8 *gtf = (u8 *)(gtf_address + ix * REGS_PER_GTF);
 307                 struct ide_cmd cmd;
 308
 309                 DEBPRINT("(0x1f1-1f7): "
 310                          "hex: %02x %02x %02x %02x %02x %02x %02x\n",
 311                          gtf[0], gtf[1], gtf[2],
 312                          gtf[3], gtf[4], gtf[5], gtf[6]);
 313
 314                 if (!ide_acpigtf) {
 315                         DEBPRINT("_GTF execution disabled\n");
 316                         continue;
 317                 }
 318
 319                 /* convert GTF to taskfile */
 320                 memset(&cmd, 0, sizeof(cmd));
 321                 memcpy(&cmd.tf.feature, gtf, REGS_PER_GTF);
 322                 cmd.valid.out.tf = IDE_VALID_OUT_TF | IDE_VALID_DEVICE;
 323                 cmd.valid.in.tf  = IDE_VALID_IN_TF  | IDE_VALID_DEVICE;
 324
 325                 err = ide_no_data_taskfile(drive, &cmd);
 326                 if (err) {
 327                         printk(KERN_ERR "%s: ide_no_data_taskfile failed: %u\n",
 328                                         __func__, err);
 329                         rc = err;
 330                 }
 331         }
 332
 333         return rc;
 334 }
 335
 336 /**
 337  * ide_acpi_exec_tfs - get then write drive taskfile settings
 338  * @drive: the drive for which the taskfile settings should be
 339  *         written.
 340  *
 341  * According to the ACPI spec this should be called after _STM
 342  * has been evaluated for the interface. Some ACPI vendors interpret
 343  * that as a hard requirement and modify the taskfile according
 344  * to the Identify Drive information passed down with _STM.
 345  * So one should really make sure to call this only after _STM has
 346  * been executed.
 347  */
 348 int ide_acpi_exec_tfs(ide_drive_t *drive)
 349 {
 350         int             ret;
 351         unsigned int    gtf_length;
 352         unsigned long   gtf_address;
 353         unsigned long   obj_loc;
 354
 355         if (ide_noacpi)
 356                 return 0;
 357
 358         DEBPRINT("call get_GTF, drive=%s port=%d\n", drive->name, drive->dn);
 359
 360         ret = do_drive_get_GTF(drive, &gtf_length, &gtf_address, &obj_loc);
 361         if (ret < 0) {
 362                 DEBPRINT("get_GTF error (%d)\n", ret);
 363                 return ret;
 364         }
 365
 366         DEBPRINT("call set_taskfiles, drive=%s\n", drive->name);
 367
 368         ret = do_drive_set_taskfiles(drive, gtf_length, gtf_address);
 369         kfree((void *)obj_loc);
 370         if (ret < 0) {
 371                 DEBPRINT("set_taskfiles error (%d)\n", ret);
 372         }
 373
 374         DEBPRINT("ret=%d\n", ret);
 375
 376         return ret;
 377 }
 378
 379 /**
 380  * ide_acpi_get_timing - get the channel (controller) timings
 381  * @hwif: target IDE interface (channel)
 382  *
 383  * This function executes the _GTM ACPI method for the target channel.
 384  *
 385  */
 386 void ide_acpi_get_timing(ide_hwif_t *hwif)
 387 {
 388         acpi_status             status;
 389         struct acpi_buffer      output;
 390         union acpi_object       *out_obj;
 391
 392         if (ide_noacpi)
 393                 return;
 394
 395         DEBPRINT("ENTER:\n");
 396
 397         if (!hwif->acpidata) {
 398                 DEBPRINT("no ACPI data for %s\n", hwif->name);
 399                 return;
 400         }
 401
 402         /* Setting up output buffer for _GTM */
 403         output.length = ACPI_ALLOCATE_BUFFER;
 404         output.pointer = NULL;  /* ACPI-CA sets this; save/free it later */
 405
 406         /* _GTM has no input parameters */
 407         status = acpi_evaluate_object(hwif->acpidata->obj_handle, "_GTM",
 408                                       NULL, &output);
 409
 410         DEBPRINT("_GTM status: %d, outptr: 0x%p, outlen: 0x%llx\n",
 411                  status, output.pointer,
 412                  (unsigned long long)output.length);
 413
 414         if (ACPI_FAILURE(status)) {
 415                 DEBPRINT("Run _GTM error: status = 0x%x\n", status);
 416                 return;
 417         }
 418
 419         if (!output.length || !output.pointer) {
 420                 DEBPRINT("Run _GTM: length or ptr is NULL (0x%llx, 0x%p)\n",
 421                        (unsigned long long)output.length,
 422                        output.pointer);
 423                 kfree(output.pointer);
 424                 return;
 425         }
 426
 427         out_obj = output.pointer;
 428         if (out_obj->type != ACPI_TYPE_BUFFER) {
 429                 kfree(output.pointer);
 430                 DEBPRINT("Run _GTM: error: "
 431                        "expected object type of ACPI_TYPE_BUFFER, "
 432                        "got 0x%x\n", out_obj->type);
 433                 return;
 434         }
 435
 436         if (!out_obj->buffer.length || !out_obj->buffer.pointer ||
 437             out_obj->buffer.length != sizeof(struct GTM_buffer)) {
 438                 kfree(output.pointer);
 439                 printk(KERN_ERR
 440                         "%s: unexpected _GTM length (0x%x)[should be 0x%zx] or "
 441                         "addr (0x%p)\n",
 442                         __func__, out_obj->buffer.length,
 443                         sizeof(struct GTM_buffer), out_obj->buffer.pointer);
 444                 return;
 445         }
 446
 447         memcpy(&hwif->acpidata->gtm, out_obj->buffer.pointer,
 448                sizeof(struct GTM_buffer));
 449
 450         DEBPRINT("_GTM info: ptr: 0x%p, len: 0x%x, exp.len: 0x%Zx\n",
 451                  out_obj->buffer.pointer, out_obj->buffer.length,
 452                  sizeof(struct GTM_buffer));
 453
 454         DEBPRINT("_GTM fields: 0x%x, 0x%x, 0x%x, 0x%x, 0x%x\n",
 455                  hwif->acpidata->gtm.PIO_speed0,
 456                  hwif->acpidata->gtm.DMA_speed0,
 457                  hwif->acpidata->gtm.PIO_speed1,
 458                  hwif->acpidata->gtm.DMA_speed1,
 459                  hwif->acpidata->gtm.GTM_flags);
 460
 461         kfree(output.pointer);
 462 }
 463
 464 /**
 465  * ide_acpi_push_timing - set the channel (controller) timings
 466  * @hwif: target IDE interface (channel)
 467  *
 468  * This function executes the _STM ACPI method for the target channel.
 469  *
 470  * _STM requires Identify Drive data, which has to passed as an argument.
 471  * Unfortunately drive->id is a mangled version which we can't readily
 472  * use; hence we'll get the information afresh.
 473  */
 474 void ide_acpi_push_timing(ide_hwif_t *hwif)
 475 {
 476         acpi_status             status;
 477         struct acpi_object_list input;
 478         union acpi_object       in_params[3];
 479         struct ide_acpi_drive_link      *master = &hwif->acpidata->master;
 480         struct ide_acpi_drive_link      *slave = &hwif->acpidata->slave;
 481
 482         if (ide_noacpi)
 483                 return;
 484
 485         DEBPRINT("ENTER:\n");
 486
 487         if (!hwif->acpidata) {
 488                 DEBPRINT("no ACPI data for %s\n", hwif->name);
 489                 return;
 490         }
 491
 492         /* Give the GTM buffer + drive Identify data to the channel via the
 493          * _STM method: */
 494         /* setup input parameters buffer for _STM */
 495         input.count = 3;
 496         input.pointer = in_params;
 497         in_params[0].type = ACPI_TYPE_BUFFER;
 498         in_params[0].buffer.length = sizeof(struct GTM_buffer);
 499         in_params[0].buffer.pointer = (u8 *)&hwif->acpidata->gtm;
 500         in_params[1].type = ACPI_TYPE_BUFFER;
 501         in_params[1].buffer.length = ATA_ID_WORDS * 2;
 502         in_params[1].buffer.pointer = (u8 *)&master->idbuff;
 503         in_params[2].type = ACPI_TYPE_BUFFER;
 504         in_params[2].buffer.length = ATA_ID_WORDS * 2;
 505         in_params[2].buffer.pointer = (u8 *)&slave->idbuff;
 506         /* Output buffer: _STM has no output */
 507
 508         status = acpi_evaluate_object(hwif->acpidata->obj_handle, "_STM",
 509                                       &input, NULL);
 510
 511         if (ACPI_FAILURE(status)) {
 512                 DEBPRINT("Run _STM error: status = 0x%x\n", status);
 513         }
 514         DEBPRINT("_STM status: %d\n", status);
 515 }
 516
 517 /**
 518  * ide_acpi_set_state - set the channel power state
 519  * @hwif: target IDE interface
 520  * @on: state, on/off
 521  *
 522  * This function executes the _PS0/_PS3 ACPI method to set the power state.
 523  * ACPI spec requires _PS0 when IDE power on and _PS3 when power off
 524  */
 525 void ide_acpi_set_state(ide_hwif_t *hwif, int on)
 526 {
 527         ide_drive_t *drive;
 528         int i;
 529
 530         if (ide_noacpi || ide_noacpi_psx)
 531                 return;
 532
 533         DEBPRINT("ENTER:\n");
 534
 535         if (!hwif->acpidata) {
 536                 DEBPRINT("no ACPI data for %s\n", hwif->name);
 537                 return;
 538         }
 539
 540         /* channel first and then drives for power on and verse versa for power off */
 541         if (on)
 542                 acpi_bus_set_power(hwif->acpidata->obj_handle, ACPI_STATE_D0);
 543
 544         ide_port_for_each_present_dev(i, drive, hwif) {
 545                 if (drive->acpidata->obj_handle)
 546                         acpi_bus_set_power(drive->acpidata->obj_handle,
 547                                            on ? ACPI_STATE_D0 : ACPI_STATE_D3);
 548         }
 549
 550         if (!on)
 551                 acpi_bus_set_power(hwif->acpidata->obj_handle, ACPI_STATE_D3);
 552 }
 553
 554 /**
 555  * ide_acpi_init_port - initialize the ACPI link for an IDE interface
 556  * @hwif: target IDE interface (channel)
 557  *
 558  * The ACPI spec is not quite clear when the drive identify buffer
 559  * should be obtained. Calling IDENTIFY DEVICE during shutdown
 560  * is not the best of ideas as the drive might already being put to
 561  * sleep. And obviously we can't call it during resume.
 562  * So we get the information during startup; but this means that
 563  * any changes during run-time will be lost after resume.
 564  */
 565 void ide_acpi_init_port(ide_hwif_t *hwif)
 566 {
 567         hwif->acpidata = kzalloc(sizeof(struct ide_acpi_hwif_link), GFP_KERNEL);
 568         if (!hwif->acpidata)
 569                 return;
 570
 571         hwif->acpidata->obj_handle = ide_acpi_hwif_get_handle(hwif);
 572         if (!hwif->acpidata->obj_handle) {
 573                 DEBPRINT("no ACPI object for %s found\n", hwif->name);
 574                 kfree(hwif->acpidata);
 575                 hwif->acpidata = NULL;
 576         }
 577 }
 578
 579 void ide_acpi_port_init_devices(ide_hwif_t *hwif)
 580 {
 581         ide_drive_t *drive;
 582         int i, err;
 583
 584         if (hwif->acpidata == NULL)
 585                 return;
 586
 587         /*
 588          * The ACPI spec mandates that we send information
 589          * for both drives, regardless whether they are connected
 590          * or not.
 591          */
 592         hwif->devices[0]->acpidata = &hwif->acpidata->master;
 593         hwif->devices[1]->acpidata = &hwif->acpidata->slave;
 594
 595         /* get _ADR info for each device */
 596         ide_port_for_each_present_dev(i, drive, hwif) {
 597                 acpi_handle dev_handle;
 598
 599                 DEBPRINT("ENTER: %s at channel#: %d port#: %d\n",
 600                          drive->name, hwif->channel, drive->dn & 1);
 601
 602                 /* TBD: could also check ACPI object VALID bits */
 603                 dev_handle = acpi_get_child(hwif->acpidata->obj_handle,
 604                                             drive->dn & 1);
 605
 606                 DEBPRINT("drive %s handle 0x%p\n", drive->name, dev_handle);
 607
 608                 drive->acpidata->obj_handle = dev_handle;
 609         }
 610
 611         /* send IDENTIFY for each device */
 612         ide_port_for_each_present_dev(i, drive, hwif) {
 613                 err = taskfile_lib_get_identify(drive, drive->acpidata->idbuff);
 614                 if (err)
 615                         DEBPRINT("identify device %s failed (%d)\n",
 616                                  drive->name, err);
 617         }
 618
 619         if (!ide_acpionboot) {
 620                 DEBPRINT("ACPI methods disabled on boot\n");
 621                 return;
 622         }
 623
 624         /* ACPI _PS0 before _STM */
 625         ide_acpi_set_state(hwif, 1);
 626         /*
 627          * ACPI requires us to call _STM on startup
 628          */
 629         ide_acpi_get_timing(hwif);
 630         ide_acpi_push_timing(hwif);
 631
 632         ide_port_for_each_present_dev(i, drive, hwif) {
 633                 ide_acpi_exec_tfs(drive);
 634         }
 635 }