reactos/drivers/bus/acpi/acpica/namespace/nsinit.c

   1 /******************************************************************************
   2  *
   3  * Module Name: nsinit - namespace initialization
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2016, Intel Corp.
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions, and the following disclaimer,
  16  *    without modification.
  17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18  *    substantially similar to the "NO WARRANTY" disclaimer below
  19  *    ("Disclaimer") and any redistribution must be conditioned upon
  20  *    including a substantially similar Disclaimer requirement for further
  21  *    binary redistribution.
  22  * 3. Neither the names of the above-listed copyright holders nor the names
  23  *    of any contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * Alternatively, this software may be distributed under the terms of the
  27  * GNU General Public License ("GPL") version 2 as published by the Free
  28  * Software Foundation.
  29  *
  30  * NO WARRANTY
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGES.
  42  */
  43
  44 #include "acpi.h"
  45 #include "accommon.h"
  46 #include "acnamesp.h"
  47 #include "acdispat.h"
  48 #include "acinterp.h"
  49 #include "acevents.h"
  50
  51 #define _COMPONENT          ACPI_NAMESPACE
  52         ACPI_MODULE_NAME    ("nsinit")
  53
  54 /* Local prototypes */
  55
  56 static ACPI_STATUS
  57 AcpiNsInitOneObject (
  58     ACPI_HANDLE             ObjHandle,
  59     UINT32                  Level,
  60     void                    *Context,
  61     void                    **ReturnValue);
  62
  63 static ACPI_STATUS
  64 AcpiNsInitOneDevice (
  65     ACPI_HANDLE             ObjHandle,
  66     UINT32                  NestingLevel,
  67     void                    *Context,
  68     void                    **ReturnValue);
  69
  70 static ACPI_STATUS
  71 AcpiNsFindIniMethods (
  72     ACPI_HANDLE             ObjHandle,
  73     UINT32                  NestingLevel,
  74     void                    *Context,
  75     void                    **ReturnValue);
  76
  77
  78 /*******************************************************************************
  79  *
  80  * FUNCTION:    AcpiNsInitializeObjects
  81  *
  82  * PARAMETERS:  None
  83  *
  84  * RETURN:      Status
  85  *
  86  * DESCRIPTION: Walk the entire namespace and perform any necessary
  87  *              initialization on the objects found therein
  88  *
  89  ******************************************************************************/
  90
  91 ACPI_STATUS
  92 AcpiNsInitializeObjects (
  93     void)
  94 {
  95     ACPI_STATUS             Status;
  96     ACPI_INIT_WALK_INFO     Info;
  97
  98
  99     ACPI_FUNCTION_TRACE (NsInitializeObjects);
 100
 101
 102     ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
 103         "[Init] Completing Initialization of ACPI Objects\n"));
 104     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
 105         "**** Starting initialization of namespace objects ****\n"));
 106     ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INIT,
 107         "Completing Region/Field/Buffer/Package initialization:\n"));
 108
 109     /* Set all init info to zero */
 110
 111     memset (&Info, 0, sizeof (ACPI_INIT_WALK_INFO));
 112
 113     /* Walk entire namespace from the supplied root */
 114
 115     Status = AcpiWalkNamespace (ACPI_TYPE_ANY, ACPI_ROOT_OBJECT,
 116         ACPI_UINT32_MAX, AcpiNsInitOneObject, NULL,
 117         &Info, NULL);
 118     if (ACPI_FAILURE (Status))
 119     {
 120         ACPI_EXCEPTION ((AE_INFO, Status, "During WalkNamespace"));
 121     }
 122
 123     ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INIT,
 124         "    Initialized %u/%u Regions %u/%u Fields %u/%u "
 125         "Buffers %u/%u Packages (%u nodes)\n",
 126         Info.OpRegionInit,  Info.OpRegionCount,
 127         Info.FieldInit,     Info.FieldCount,
 128         Info.BufferInit,    Info.BufferCount,
 129         Info.PackageInit,   Info.PackageCount, Info.ObjectCount));
 130
 131     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
 132         "%u Control Methods found\n%u Op Regions found\n",
 133         Info.MethodCount, Info.OpRegionCount));
 134
 135     return_ACPI_STATUS (AE_OK);
 136 }
 137
 138
 139 /*******************************************************************************
 140  *
 141  * FUNCTION:    AcpiNsInitializeDevices
 142  *
 143  * PARAMETERS:  None
 144  *
 145  * RETURN:      ACPI_STATUS
 146  *
 147  * DESCRIPTION: Walk the entire namespace and initialize all ACPI devices.
 148  *              This means running _INI on all present devices.
 149  *
 150  *              Note: We install PCI config space handler on region access,
 151  *              not here.
 152  *
 153  ******************************************************************************/
 154
 155 ACPI_STATUS
 156 AcpiNsInitializeDevices (
 157     UINT32                  Flags)
 158 {
 159     ACPI_STATUS             Status = AE_OK;
 160     ACPI_DEVICE_WALK_INFO   Info;
 161     ACPI_HANDLE             Handle;
 162
 163
 164     ACPI_FUNCTION_TRACE (NsInitializeDevices);
 165
 166
 167     if (!(Flags & ACPI_NO_DEVICE_INIT))
 168     {
 169         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
 170             "[Init] Initializing ACPI Devices\n"));
 171
 172         /* Init counters */
 173
 174         Info.DeviceCount = 0;
 175         Info.Num_STA = 0;
 176         Info.Num_INI = 0;
 177
 178         ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INIT,
 179             "Initializing Device/Processor/Thermal objects "
 180             "and executing _INI/_STA methods:\n"));
 181
 182         /* Tree analysis: find all subtrees that contain _INI methods */
 183
 184         Status = AcpiNsWalkNamespace (ACPI_TYPE_ANY, ACPI_ROOT_OBJECT,
 185             ACPI_UINT32_MAX, FALSE, AcpiNsFindIniMethods, NULL, &Info, NULL);
 186         if (ACPI_FAILURE (Status))
 187         {
 188             goto ErrorExit;
 189         }
 190
 191         /* Allocate the evaluation information block */
 192
 193         Info.EvaluateInfo = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_EVALUATE_INFO));
 194         if (!Info.EvaluateInfo)
 195         {
 196             Status = AE_NO_MEMORY;
 197             goto ErrorExit;
 198         }
 199
 200         /*
 201          * Execute the "global" _INI method that may appear at the root.
 202          * This support is provided for Windows compatibility (Vista+) and
 203          * is not part of the ACPI specification.
 204          */
 205         Info.EvaluateInfo->PrefixNode = AcpiGbl_RootNode;
 206         Info.EvaluateInfo->RelativePathname = METHOD_NAME__INI;
 207         Info.EvaluateInfo->Parameters = NULL;
 208         Info.EvaluateInfo->Flags = ACPI_IGNORE_RETURN_VALUE;
 209
 210         Status = AcpiNsEvaluate (Info.EvaluateInfo);
 211         if (ACPI_SUCCESS (Status))
 212         {
 213             Info.Num_INI++;
 214         }
 215
 216         /*
 217          * Execute \_SB._INI.
 218          * There appears to be a strict order requirement for \_SB._INI,
 219          * which should be evaluated before any _REG evaluations.
 220          */
 221         Status = AcpiGetHandle (NULL, "\\_SB", &Handle);
 222         if (ACPI_SUCCESS (Status))
 223         {
 224             memset (Info.EvaluateInfo, 0, sizeof (ACPI_EVALUATE_INFO));
 225             Info.EvaluateInfo->PrefixNode = Handle;
 226             Info.EvaluateInfo->RelativePathname = METHOD_NAME__INI;
 227             Info.EvaluateInfo->Parameters = NULL;
 228             Info.EvaluateInfo->Flags = ACPI_IGNORE_RETURN_VALUE;
 229
 230             Status = AcpiNsEvaluate (Info.EvaluateInfo);
 231             if (ACPI_SUCCESS (Status))
 232             {
 233                 Info.Num_INI++;
 234             }
 235         }
 236     }
 237
 238     /*
 239      * Run all _REG methods
 240      *
 241      * Note: Any objects accessed by the _REG methods will be automatically
 242      * initialized, even if they contain executable AML (see the call to
 243      * AcpiNsInitializeObjects below).
 244      *
 245      * Note: According to the ACPI specification, we actually needn't execute
 246      * _REG for SystemMemory/SystemIo operation regions, but for PCI_Config
 247      * operation regions, it is required to evaluate _REG for those on a PCI
 248      * root bus that doesn't contain _BBN object. So this code is kept here
 249      * in order not to break things.
 250      */
 251     if (!(Flags & ACPI_NO_ADDRESS_SPACE_INIT))
 252     {
 253         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
 254             "[Init] Executing _REG OpRegion methods\n"));
 255
 256         Status = AcpiEvInitializeOpRegions ();
 257         if (ACPI_FAILURE (Status))
 258         {
 259             goto ErrorExit;
 260         }
 261     }
 262
 263     if (!(Flags & ACPI_NO_DEVICE_INIT))
 264     {
 265         /* Walk namespace to execute all _INIs on present devices */
 266
 267         Status = AcpiNsWalkNamespace (ACPI_TYPE_ANY, ACPI_ROOT_OBJECT,
 268             ACPI_UINT32_MAX, FALSE, AcpiNsInitOneDevice, NULL, &Info, NULL);
 269
 270         /*
 271          * Any _OSI requests should be completed by now. If the BIOS has
 272          * requested any Windows OSI strings, we will always truncate
 273          * I/O addresses to 16 bits -- for Windows compatibility.
 274          */
 275         if (AcpiGbl_OsiData >= ACPI_OSI_WIN_2000)
 276         {
 277             AcpiGbl_TruncateIoAddresses = TRUE;
 278         }
 279
 280         ACPI_FREE (Info.EvaluateInfo);
 281         if (ACPI_FAILURE (Status))
 282         {
 283             goto ErrorExit;
 284         }
 285
 286         ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INIT,
 287             "    Executed %u _INI methods requiring %u _STA executions "
 288             "(examined %u objects)\n",
 289             Info.Num_INI, Info.Num_STA, Info.DeviceCount));
 290     }
 291
 292     return_ACPI_STATUS (Status);
 293
 294
 295 ErrorExit:
 296     ACPI_EXCEPTION ((AE_INFO, Status, "During device initialization"));
 297     return_ACPI_STATUS (Status);
 298 }
 299
 300
 301 /*******************************************************************************
 302  *
 303  * FUNCTION:    AcpiNsInitOneObject
 304  *
 305  * PARAMETERS:  ObjHandle       - Node
 306  *              Level           - Current nesting level
 307  *              Context         - Points to a init info struct
 308  *              ReturnValue     - Not used
 309  *
 310  * RETURN:      Status
 311  *
 312  * DESCRIPTION: Callback from AcpiWalkNamespace. Invoked for every object
 313  *              within the  namespace.
 314  *
 315  *              Currently, the only objects that require initialization are:
 316  *              1) Methods
 317  *              2) Op Regions
 318  *
 319  ******************************************************************************/
 320
 321 static ACPI_STATUS
 322 AcpiNsInitOneObject (
 323     ACPI_HANDLE             ObjHandle,
 324     UINT32                  Level,
 325     void                    *Context,
 326     void                    **ReturnValue)
 327 {
 328     ACPI_OBJECT_TYPE        Type;
 329     ACPI_STATUS             Status = AE_OK;
 330     ACPI_INIT_WALK_INFO     *Info = (ACPI_INIT_WALK_INFO *) Context;
 331     ACPI_NAMESPACE_NODE     *Node = (ACPI_NAMESPACE_NODE *) ObjHandle;
 332     ACPI_OPERAND_OBJECT     *ObjDesc;
 333
 334
 335     ACPI_FUNCTION_NAME (NsInitOneObject);
 336
 337
 338     Info->ObjectCount++;
 339
 340     /* And even then, we are only interested in a few object types */
 341
 342     Type = AcpiNsGetType (ObjHandle);
 343     ObjDesc = AcpiNsGetAttachedObject (Node);
 344     if (!ObjDesc)
 345     {
 346         return (AE_OK);
 347     }
 348
 349     /* Increment counters for object types we are looking for */
 350
 351     switch (Type)
 352     {
 353     case ACPI_TYPE_REGION:
 354
 355         Info->OpRegionCount++;
 356         break;
 357
 358     case ACPI_TYPE_BUFFER_FIELD:
 359
 360         Info->FieldCount++;
 361         break;
 362
 363     case ACPI_TYPE_LOCAL_BANK_FIELD:
 364
 365         Info->FieldCount++;
 366         break;
 367
 368     case ACPI_TYPE_BUFFER:
 369
 370         Info->BufferCount++;
 371         break;
 372
 373     case ACPI_TYPE_PACKAGE:
 374
 375         Info->PackageCount++;
 376         break;
 377
 378     default:
 379
 380         /* No init required, just exit now */
 381
 382         return (AE_OK);
 383     }
 384
 385     /* If the object is already initialized, nothing else to do */
 386
 387     if (ObjDesc->Common.Flags & AOPOBJ_DATA_VALID)
 388     {
 389         return (AE_OK);
 390     }
 391
 392     /* Must lock the interpreter before executing AML code */
 393
 394     AcpiExEnterInterpreter ();
 395
 396     /*
 397      * Each of these types can contain executable AML code within the
 398      * declaration.
 399      */
 400     switch (Type)
 401     {
 402     case ACPI_TYPE_REGION:
 403
 404         Info->OpRegionInit++;
 405         Status = AcpiDsGetRegionArguments (ObjDesc);
 406         break;
 407
 408     case ACPI_TYPE_BUFFER_FIELD:
 409
 410         Info->FieldInit++;
 411         Status = AcpiDsGetBufferFieldArguments (ObjDesc);
 412         break;
 413
 414     case ACPI_TYPE_LOCAL_BANK_FIELD:
 415
 416         Info->FieldInit++;
 417         Status = AcpiDsGetBankFieldArguments (ObjDesc);
 418         break;
 419
 420     case ACPI_TYPE_BUFFER:
 421
 422         Info->BufferInit++;
 423         Status = AcpiDsGetBufferArguments (ObjDesc);
 424         break;
 425
 426     case ACPI_TYPE_PACKAGE:
 427
 428         Info->PackageInit++;
 429         Status = AcpiDsGetPackageArguments (ObjDesc);
 430         break;
 431
 432     default:
 433
 434         /* No other types can get here */
 435
 436         break;
 437     }
 438
 439     if (ACPI_FAILURE (Status))
 440     {
 441         ACPI_EXCEPTION ((AE_INFO, Status,
 442             "Could not execute arguments for [%4.4s] (%s)",
 443             AcpiUtGetNodeName (Node), AcpiUtGetTypeName (Type)));
 444     }
 445
 446     /*
 447      * We ignore errors from above, and always return OK, since we don't want
 448      * to abort the walk on any single error.
 449      */
 450     AcpiExExitInterpreter ();
 451     return (AE_OK);
 452 }
 453
 454
 455 /*******************************************************************************
 456  *
 457  * FUNCTION:    AcpiNsFindIniMethods
 458  *
 459  * PARAMETERS:  ACPI_WALK_CALLBACK
 460  *
 461  * RETURN:      ACPI_STATUS
 462  *
 463  * DESCRIPTION: Called during namespace walk. Finds objects named _INI under
 464  *              device/processor/thermal objects, and marks the entire subtree
 465  *              with a SUBTREE_HAS_INI flag. This flag is used during the
 466  *              subsequent device initialization walk to avoid entire subtrees
 467  *              that do not contain an _INI.
 468  *
 469  ******************************************************************************/
 470
 471 static ACPI_STATUS
 472 AcpiNsFindIniMethods (
 473     ACPI_HANDLE             ObjHandle,
 474     UINT32                  NestingLevel,
 475     void                    *Context,
 476     void                    **ReturnValue)
 477 {
 478     ACPI_DEVICE_WALK_INFO   *Info = ACPI_CAST_PTR (ACPI_DEVICE_WALK_INFO, Context);
 479     ACPI_NAMESPACE_NODE     *Node;
 480     ACPI_NAMESPACE_NODE     *ParentNode;
 481
 482
 483     /* Keep count of device/processor/thermal objects */
 484
 485     Node = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, ObjHandle);
 486     if ((Node->Type == ACPI_TYPE_DEVICE)    ||
 487         (Node->Type == ACPI_TYPE_PROCESSOR) ||
 488         (Node->Type == ACPI_TYPE_THERMAL))
 489     {
 490         Info->DeviceCount++;
 491         return (AE_OK);
 492     }
 493
 494     /* We are only looking for methods named _INI */
 495
 496     if (!ACPI_COMPARE_NAME (Node->Name.Ascii, METHOD_NAME__INI))
 497     {
 498         return (AE_OK);
 499     }
 500
 501     /*
 502      * The only _INI methods that we care about are those that are
 503      * present under Device, Processor, and Thermal objects.
 504      */
 505     ParentNode = Node->Parent;
 506     switch (ParentNode->Type)
 507     {
 508     case ACPI_TYPE_DEVICE:
 509     case ACPI_TYPE_PROCESSOR:
 510     case ACPI_TYPE_THERMAL:
 511
 512         /* Mark parent and bubble up the INI present flag to the root */
 513
 514         while (ParentNode)
 515         {
 516             ParentNode->Flags |= ANOBJ_SUBTREE_HAS_INI;
 517             ParentNode = ParentNode->Parent;
 518         }
 519         break;
 520
 521     default:
 522
 523         break;
 524     }
 525
 526     return (AE_OK);
 527 }
 528
 529
 530 /*******************************************************************************
 531  *
 532  * FUNCTION:    AcpiNsInitOneDevice
 533  *
 534  * PARAMETERS:  ACPI_WALK_CALLBACK
 535  *
 536  * RETURN:      ACPI_STATUS
 537  *
 538  * DESCRIPTION: This is called once per device soon after ACPI is enabled
 539  *              to initialize each device. It determines if the device is
 540  *              present, and if so, calls _INI.
 541  *
 542  ******************************************************************************/
 543
 544 static ACPI_STATUS
 545 AcpiNsInitOneDevice (
 546     ACPI_HANDLE             ObjHandle,
 547     UINT32                  NestingLevel,
 548     void                    *Context,
 549     void                    **ReturnValue)
 550 {
 551     ACPI_DEVICE_WALK_INFO   *WalkInfo = ACPI_CAST_PTR (ACPI_DEVICE_WALK_INFO, Context);
 552     ACPI_EVALUATE_INFO      *Info = WalkInfo->EvaluateInfo;
 553     UINT32                  Flags;
 554     ACPI_STATUS             Status;
 555     ACPI_NAMESPACE_NODE     *DeviceNode;
 556
 557
 558     ACPI_FUNCTION_TRACE (NsInitOneDevice);
 559
 560
 561     /* We are interested in Devices, Processors and ThermalZones only */
 562
 563     DeviceNode = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, ObjHandle);
 564     if ((DeviceNode->Type != ACPI_TYPE_DEVICE)    &&
 565         (DeviceNode->Type != ACPI_TYPE_PROCESSOR) &&
 566         (DeviceNode->Type != ACPI_TYPE_THERMAL))
 567     {
 568         return_ACPI_STATUS (AE_OK);
 569     }
 570
 571     /*
 572      * Because of an earlier namespace analysis, all subtrees that contain an
 573      * _INI method are tagged.
 574      *
 575      * If this device subtree does not contain any _INI methods, we
 576      * can exit now and stop traversing this entire subtree.
 577      */
 578     if (!(DeviceNode->Flags & ANOBJ_SUBTREE_HAS_INI))
 579     {
 580         return_ACPI_STATUS (AE_CTRL_DEPTH);
 581     }
 582
 583     /*
 584      * Run _STA to determine if this device is present and functioning. We
 585      * must know this information for two important reasons (from ACPI spec):
 586      *
 587      * 1) We can only run _INI if the device is present.
 588      * 2) We must abort the device tree walk on this subtree if the device is
 589      *    not present and is not functional (we will not examine the children)
 590      *
 591      * The _STA method is not required to be present under the device, we
 592      * assume the device is present if _STA does not exist.
 593      */
 594     ACPI_DEBUG_EXEC (AcpiUtDisplayInitPathname (
 595         ACPI_TYPE_METHOD, DeviceNode, METHOD_NAME__STA));
 596
 597     Status = AcpiUtExecute_STA (DeviceNode, &Flags);
 598     if (ACPI_FAILURE (Status))
 599     {
 600         /* Ignore error and move on to next device */
 601
 602         return_ACPI_STATUS (AE_OK);
 603     }
 604
 605     /*
 606      * Flags == -1 means that _STA was not found. In this case, we assume that
 607      * the device is both present and functional.
 608      *
 609      * From the ACPI spec, description of _STA:
 610      *
 611      * "If a device object (including the processor object) does not have an
 612      * _STA object, then OSPM assumes that all of the above bits are set (in
 613      * other words, the device is present, ..., and functioning)"
 614      */
 615     if (Flags != ACPI_UINT32_MAX)
 616     {
 617         WalkInfo->Num_STA++;
 618     }
 619
 620     /*
 621      * Examine the PRESENT and FUNCTIONING status bits
 622      *
 623      * Note: ACPI spec does not seem to specify behavior for the present but
 624      * not functioning case, so we assume functioning if present.
 625      */
 626     if (!(Flags & ACPI_STA_DEVICE_PRESENT))
 627     {
 628         /* Device is not present, we must examine the Functioning bit */
 629
 630         if (Flags & ACPI_STA_DEVICE_FUNCTIONING)
 631         {
 632             /*
 633              * Device is not present but is "functioning". In this case,
 634              * we will not run _INI, but we continue to examine the children
 635              * of this device.
 636              *
 637              * From the ACPI spec, description of _STA: (Note - no mention
 638              * of whether to run _INI or not on the device in question)
 639              *
 640              * "_STA may return bit 0 clear (not present) with bit 3 set
 641              * (device is functional). This case is used to indicate a valid
 642              * device for which no device driver should be loaded (for example,
 643              * a bridge device.) Children of this device may be present and
 644              * valid. OSPM should continue enumeration below a device whose
 645              * _STA returns this bit combination"
 646              */
 647             return_ACPI_STATUS (AE_OK);
 648         }
 649         else
 650         {
 651             /*
 652              * Device is not present and is not functioning. We must abort the
 653              * walk of this subtree immediately -- don't look at the children
 654              * of such a device.
 655              *
 656              * From the ACPI spec, description of _INI:
 657              *
 658              * "If the _STA method indicates that the device is not present,
 659              * OSPM will not run the _INI and will not examine the children
 660              * of the device for _INI methods"
 661              */
 662             return_ACPI_STATUS (AE_CTRL_DEPTH);
 663         }
 664     }
 665
 666     /*
 667      * The device is present or is assumed present if no _STA exists.
 668      * Run the _INI if it exists (not required to exist)
 669      *
 670      * Note: We know there is an _INI within this subtree, but it may not be
 671      * under this particular device, it may be lower in the branch.
 672      */
 673     if (!ACPI_COMPARE_NAME (DeviceNode->Name.Ascii, "_SB_") ||
 674         DeviceNode->Parent != AcpiGbl_RootNode)
 675     {
 676         ACPI_DEBUG_EXEC (AcpiUtDisplayInitPathname (
 677             ACPI_TYPE_METHOD, DeviceNode, METHOD_NAME__INI));
 678
 679         memset (Info, 0, sizeof (ACPI_EVALUATE_INFO));
 680         Info->PrefixNode = DeviceNode;
 681         Info->RelativePathname = METHOD_NAME__INI;
 682         Info->Parameters = NULL;
 683         Info->Flags = ACPI_IGNORE_RETURN_VALUE;
 684
 685         Status = AcpiNsEvaluate (Info);
 686         if (ACPI_SUCCESS (Status))
 687         {
 688             WalkInfo->Num_INI++;
 689         }
 690
 691 #ifdef ACPI_DEBUG_OUTPUT
 692         else if (Status != AE_NOT_FOUND)
 693         {
 694             /* Ignore error and move on to next device */
 695
 696             char *ScopeName = AcpiNsGetNormalizedPathname (DeviceNode, TRUE);
 697
 698             ACPI_EXCEPTION ((AE_INFO, Status, "during %s._INI execution",
 699                 ScopeName));
 700             ACPI_FREE (ScopeName);
 701         }
 702 #endif
 703     }
 704
 705     /* Ignore errors from above */
 706
 707     Status = AE_OK;
 708
 709     /*
 710      * The _INI method has been run if present; call the Global Initialization
 711      * Handler for this device.
 712      */
 713     if (AcpiGbl_InitHandler)
 714     {
 715         Status = AcpiGbl_InitHandler (DeviceNode, ACPI_INIT_DEVICE_INI);
 716     }
 717
 718     return_ACPI_STATUS (Status);
 719 }