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

   1 /******************************************************************************
   2  *
   3  * Module Name: nsinit - namespace initialization
   4  *
   5  *****************************************************************************/
   6
   7 /******************************************************************************
   8  *
   9  * 1. Copyright Notice
  10  *
  11  * Some or all of this work - Copyright (c) 1999 - 2011, Intel Corp.
  12  * All rights reserved.
  13  *
  14  * 2. License
  15  *
  16  * 2.1. This is your license from Intel Corp. under its intellectual property
  17  * rights.  You may have additional license terms from the party that provided
  18  * you this software, covering your right to use that party's intellectual
  19  * property rights.
  20  *
  21  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
  22  * copy of the source code appearing in this file ("Covered Code") an
  23  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
  24  * base code distributed originally by Intel ("Original Intel Code") to copy,
  25  * make derivatives, distribute, use and display any portion of the Covered
  26  * Code in any form, with the right to sublicense such rights; and
  27  *
  28  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
  29  * license (with the right to sublicense), under only those claims of Intel
  30  * patents that are infringed by the Original Intel Code, to make, use, sell,
  31  * offer to sell, and import the Covered Code and derivative works thereof
  32  * solely to the minimum extent necessary to exercise the above copyright
  33  * license, and in no event shall the patent license extend to any additions
  34  * to or modifications of the Original Intel Code.  No other license or right
  35  * is granted directly or by implication, estoppel or otherwise;
  36  *
  37  * The above copyright and patent license is granted only if the following
  38  * conditions are met:
  39  *
  40  * 3. Conditions
  41  *
  42  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
  43  * Redistribution of source code of any substantial portion of the Covered
  44  * Code or modification with rights to further distribute source must include
  45  * the above Copyright Notice, the above License, this list of Conditions,
  46  * and the following Disclaimer and Export Compliance provision.  In addition,
  47  * Licensee must cause all Covered Code to which Licensee contributes to
  48  * contain a file documenting the changes Licensee made to create that Covered
  49  * Code and the date of any change.  Licensee must include in that file the
  50  * documentation of any changes made by any predecessor Licensee.  Licensee
  51  * must include a prominent statement that the modification is derived,
  52  * directly or indirectly, from Original Intel Code.
  53  *
  54  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
  55  * Redistribution of source code of any substantial portion of the Covered
  56  * Code or modification without rights to further distribute source must
  57  * include the following Disclaimer and Export Compliance provision in the
  58  * documentation and/or other materials provided with distribution.  In
  59  * addition, Licensee may not authorize further sublicense of source of any
  60  * portion of the Covered Code, and must include terms to the effect that the
  61  * license from Licensee to its licensee is limited to the intellectual
  62  * property embodied in the software Licensee provides to its licensee, and
  63  * not to intellectual property embodied in modifications its licensee may
  64  * make.
  65  *
  66  * 3.3. Redistribution of Executable. Redistribution in executable form of any
  67  * substantial portion of the Covered Code or modification must reproduce the
  68  * above Copyright Notice, and the following Disclaimer and Export Compliance
  69  * provision in the documentation and/or other materials provided with the
  70  * distribution.
  71  *
  72  * 3.4. Intel retains all right, title, and interest in and to the Original
  73  * Intel Code.
  74  *
  75  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
  76  * Intel shall be used in advertising or otherwise to promote the sale, use or
  77  * other dealings in products derived from or relating to the Covered Code
  78  * without prior written authorization from Intel.
  79  *
  80  * 4. Disclaimer and Export Compliance
  81  *
  82  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
  83  * HERE.  ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
  84  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT,  ASSISTANCE,
  85  * INSTALLATION, TRAINING OR OTHER SERVICES.  INTEL WILL NOT PROVIDE ANY
  86  * UPDATES, ENHANCEMENTS OR EXTENSIONS.  INTEL SPECIFICALLY DISCLAIMS ANY
  87  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
  88  * PARTICULAR PURPOSE.
  89  *
  90  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
  91  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
  92  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
  93  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
  94  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
  95  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.  THESE LIMITATIONS
  96  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
  97  * LIMITED REMEDY.
  98  *
  99  * 4.3. Licensee shall not export, either directly or indirectly, any of this
 100  * software or system incorporating such software without first obtaining any
 101  * required license or other approval from the U. S. Department of Commerce or
 102  * any other agency or department of the United States Government.  In the
 103  * event Licensee exports any such software from the United States or
 104  * re-exports any such software from a foreign destination, Licensee shall
 105  * ensure that the distribution and export/re-export of the software is in
 106  * compliance with all laws, regulations, orders, or other restrictions of the
 107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
 108  * any of its subsidiaries will export/re-export any technical data, process,
 109  * software, or service, directly or indirectly, to any country for which the
 110  * United States government or any agency thereof requires an export license,
 111  * other governmental approval, or letter of assurance, without first obtaining
 112  * such license, approval or letter.
 113  *
 114  *****************************************************************************/
 115
 116
 117 #define __NSXFINIT_C__
 118
 119 #include "acpi.h"
 120 #include "accommon.h"
 121 #include "acnamesp.h"
 122 #include "acdispat.h"
 123 #include "acinterp.h"
 124
 125 #define _COMPONENT          ACPI_NAMESPACE
 126         ACPI_MODULE_NAME    ("nsinit")
 127
 128 /* Local prototypes */
 129
 130 static ACPI_STATUS
 131 AcpiNsInitOneObject (
 132     ACPI_HANDLE             ObjHandle,
 133     UINT32                  Level,
 134     void                    *Context,
 135     void                    **ReturnValue);
 136
 137 static ACPI_STATUS
 138 AcpiNsInitOneDevice (
 139     ACPI_HANDLE             ObjHandle,
 140     UINT32                  NestingLevel,
 141     void                    *Context,
 142     void                    **ReturnValue);
 143
 144 static ACPI_STATUS
 145 AcpiNsFindIniMethods (
 146     ACPI_HANDLE             ObjHandle,
 147     UINT32                  NestingLevel,
 148     void                    *Context,
 149     void                    **ReturnValue);
 150
 151
 152 /*******************************************************************************
 153  *
 154  * FUNCTION:    AcpiNsInitializeObjects
 155  *
 156  * PARAMETERS:  None
 157  *
 158  * RETURN:      Status
 159  *
 160  * DESCRIPTION: Walk the entire namespace and perform any necessary
 161  *              initialization on the objects found therein
 162  *
 163  ******************************************************************************/
 164
 165 ACPI_STATUS
 166 AcpiNsInitializeObjects (
 167     void)
 168 {
 169     ACPI_STATUS             Status;
 170     ACPI_INIT_WALK_INFO     Info;
 171
 172
 173     ACPI_FUNCTION_TRACE (NsInitializeObjects);
 174
 175
 176     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
 177         "**** Starting initialization of namespace objects ****\n"));
 178     ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INIT,
 179         "Completing Region/Field/Buffer/Package initialization:"));
 180
 181     /* Set all init info to zero */
 182
 183     ACPI_MEMSET (&Info, 0, sizeof (ACPI_INIT_WALK_INFO));
 184
 185     /* Walk entire namespace from the supplied root */
 186
 187     Status = AcpiWalkNamespace (ACPI_TYPE_ANY, ACPI_ROOT_OBJECT,
 188                 ACPI_UINT32_MAX, AcpiNsInitOneObject, NULL,
 189                 &Info, NULL);
 190     if (ACPI_FAILURE (Status))
 191     {
 192         ACPI_EXCEPTION ((AE_INFO, Status, "During WalkNamespace"));
 193     }
 194
 195     ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INIT,
 196         "\nInitialized %u/%u Regions %u/%u Fields %u/%u "
 197         "Buffers %u/%u Packages (%u nodes)\n",
 198         Info.OpRegionInit,  Info.OpRegionCount,
 199         Info.FieldInit,     Info.FieldCount,
 200         Info.BufferInit,    Info.BufferCount,
 201         Info.PackageInit,   Info.PackageCount, Info.ObjectCount));
 202
 203     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
 204         "%u Control Methods found\n", Info.MethodCount));
 205     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
 206         "%u Op Regions found\n", Info.OpRegionCount));
 207
 208     return_ACPI_STATUS (AE_OK);
 209 }
 210
 211
 212 /*******************************************************************************
 213  *
 214  * FUNCTION:    AcpiNsInitializeDevices
 215  *
 216  * PARAMETERS:  None
 217  *
 218  * RETURN:      ACPI_STATUS
 219  *
 220  * DESCRIPTION: Walk the entire namespace and initialize all ACPI devices.
 221  *              This means running _INI on all present devices.
 222  *
 223  *              Note: We install PCI config space handler on region access,
 224  *              not here.
 225  *
 226  ******************************************************************************/
 227
 228 ACPI_STATUS
 229 AcpiNsInitializeDevices (
 230     void)
 231 {
 232     ACPI_STATUS             Status;
 233     ACPI_DEVICE_WALK_INFO   Info;
 234
 235
 236     ACPI_FUNCTION_TRACE (NsInitializeDevices);
 237
 238
 239     /* Init counters */
 240
 241     Info.DeviceCount = 0;
 242     Info.Num_STA = 0;
 243     Info.Num_INI = 0;
 244
 245     ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INIT,
 246         "Initializing Device/Processor/Thermal objects "
 247         "by executing _INI methods:"));
 248
 249     /* Tree analysis: find all subtrees that contain _INI methods */
 250
 251     Status = AcpiNsWalkNamespace (ACPI_TYPE_ANY, ACPI_ROOT_OBJECT,
 252                 ACPI_UINT32_MAX, FALSE, AcpiNsFindIniMethods, NULL, &Info, NULL);
 253     if (ACPI_FAILURE (Status))
 254     {
 255         goto ErrorExit;
 256     }
 257
 258     /* Allocate the evaluation information block */
 259
 260     Info.EvaluateInfo = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_EVALUATE_INFO));
 261     if (!Info.EvaluateInfo)
 262     {
 263         Status = AE_NO_MEMORY;
 264         goto ErrorExit;
 265     }
 266
 267     /*
 268      * Execute the "global" _INI method that may appear at the root. This
 269      * support is provided for Windows compatibility (Vista+) and is not
 270      * part of the ACPI specification.
 271      */
 272     Info.EvaluateInfo->PrefixNode = AcpiGbl_RootNode;
 273     Info.EvaluateInfo->Pathname = METHOD_NAME__INI;
 274     Info.EvaluateInfo->Parameters = NULL;
 275     Info.EvaluateInfo->Flags = ACPI_IGNORE_RETURN_VALUE;
 276
 277     Status = AcpiNsEvaluate (Info.EvaluateInfo);
 278     if (ACPI_SUCCESS (Status))
 279     {
 280         Info.Num_INI++;
 281     }
 282
 283     /* Walk namespace to execute all _INIs on present devices */
 284
 285     Status = AcpiNsWalkNamespace (ACPI_TYPE_ANY, ACPI_ROOT_OBJECT,
 286                 ACPI_UINT32_MAX, FALSE, AcpiNsInitOneDevice, NULL, &Info, NULL);
 287
 288     /*
 289      * Any _OSI requests should be completed by now. If the BIOS has
 290      * requested any Windows OSI strings, we will always truncate
 291      * I/O addresses to 16 bits -- for Windows compatibility.
 292      */
 293     if (AcpiGbl_OsiData >= ACPI_OSI_WIN_2000)
 294     {
 295         AcpiGbl_TruncateIoAddresses = TRUE;
 296     }
 297
 298     ACPI_FREE (Info.EvaluateInfo);
 299     if (ACPI_FAILURE (Status))
 300     {
 301         goto ErrorExit;
 302     }
 303
 304     ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INIT,
 305         "\nExecuted %u _INI methods requiring %u _STA executions "
 306         "(examined %u objects)\n",
 307         Info.Num_INI, Info.Num_STA, Info.DeviceCount));
 308
 309     return_ACPI_STATUS (Status);
 310
 311
 312 ErrorExit:
 313     ACPI_EXCEPTION ((AE_INFO, Status, "During device initialization"));
 314     return_ACPI_STATUS (Status);
 315 }
 316
 317
 318 /*******************************************************************************
 319  *
 320  * FUNCTION:    AcpiNsInitOneObject
 321  *
 322  * PARAMETERS:  ObjHandle       - Node
 323  *              Level           - Current nesting level
 324  *              Context         - Points to a init info struct
 325  *              ReturnValue     - Not used
 326  *
 327  * RETURN:      Status
 328  *
 329  * DESCRIPTION: Callback from AcpiWalkNamespace.  Invoked for every object
 330  *              within the  namespace.
 331  *
 332  *              Currently, the only objects that require initialization are:
 333  *              1) Methods
 334  *              2) Op Regions
 335  *
 336  ******************************************************************************/
 337
 338 static ACPI_STATUS
 339 AcpiNsInitOneObject (
 340     ACPI_HANDLE             ObjHandle,
 341     UINT32                  Level,
 342     void                    *Context,
 343     void                    **ReturnValue)
 344 {
 345     ACPI_OBJECT_TYPE        Type;
 346     ACPI_STATUS             Status = AE_OK;
 347     ACPI_INIT_WALK_INFO     *Info = (ACPI_INIT_WALK_INFO *) Context;
 348     ACPI_NAMESPACE_NODE     *Node = (ACPI_NAMESPACE_NODE *) ObjHandle;
 349     ACPI_OPERAND_OBJECT     *ObjDesc;
 350
 351
 352     ACPI_FUNCTION_NAME (NsInitOneObject);
 353
 354
 355     Info->ObjectCount++;
 356
 357     /* And even then, we are only interested in a few object types */
 358
 359     Type = AcpiNsGetType (ObjHandle);
 360     ObjDesc = AcpiNsGetAttachedObject (Node);
 361     if (!ObjDesc)
 362     {
 363         return (AE_OK);
 364     }
 365
 366     /* Increment counters for object types we are looking for */
 367
 368     switch (Type)
 369     {
 370     case ACPI_TYPE_REGION:
 371         Info->OpRegionCount++;
 372         break;
 373
 374     case ACPI_TYPE_BUFFER_FIELD:
 375         Info->FieldCount++;
 376         break;
 377
 378     case ACPI_TYPE_LOCAL_BANK_FIELD:
 379         Info->FieldCount++;
 380         break;
 381
 382     case ACPI_TYPE_BUFFER:
 383         Info->BufferCount++;
 384         break;
 385
 386     case ACPI_TYPE_PACKAGE:
 387         Info->PackageCount++;
 388         break;
 389
 390     default:
 391
 392         /* No init required, just exit now */
 393         return (AE_OK);
 394     }
 395
 396     /* If the object is already initialized, nothing else to do */
 397
 398     if (ObjDesc->Common.Flags & AOPOBJ_DATA_VALID)
 399     {
 400         return (AE_OK);
 401     }
 402
 403     /* Must lock the interpreter before executing AML code */
 404
 405     AcpiExEnterInterpreter ();
 406
 407     /*
 408      * Each of these types can contain executable AML code within the
 409      * declaration.
 410      */
 411     switch (Type)
 412     {
 413     case ACPI_TYPE_REGION:
 414
 415         Info->OpRegionInit++;
 416         Status = AcpiDsGetRegionArguments (ObjDesc);
 417         break;
 418
 419     case ACPI_TYPE_BUFFER_FIELD:
 420
 421         Info->FieldInit++;
 422         Status = AcpiDsGetBufferFieldArguments (ObjDesc);
 423         break;
 424
 425     case ACPI_TYPE_LOCAL_BANK_FIELD:
 426
 427         Info->FieldInit++;
 428         Status = AcpiDsGetBankFieldArguments (ObjDesc);
 429         break;
 430
 431     case ACPI_TYPE_BUFFER:
 432
 433         Info->BufferInit++;
 434         Status = AcpiDsGetBufferArguments (ObjDesc);
 435         break;
 436
 437     case ACPI_TYPE_PACKAGE:
 438
 439         Info->PackageInit++;
 440         Status = AcpiDsGetPackageArguments (ObjDesc);
 441         break;
 442
 443     default:
 444         /* No other types can get here */
 445         break;
 446     }
 447
 448     if (ACPI_FAILURE (Status))
 449     {
 450         ACPI_EXCEPTION ((AE_INFO, Status,
 451             "Could not execute arguments for [%4.4s] (%s)",
 452             AcpiUtGetNodeName (Node), AcpiUtGetTypeName (Type)));
 453     }
 454
 455     /*
 456      * Print a dot for each object unless we are going to print the entire
 457      * pathname
 458      */
 459     if (!(AcpiDbgLevel & ACPI_LV_INIT_NAMES))
 460     {
 461         ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INIT, "."));
 462     }
 463
 464     /*
 465      * We ignore errors from above, and always return OK, since we don't want
 466      * to abort the walk on any single error.
 467      */
 468     AcpiExExitInterpreter ();
 469     return (AE_OK);
 470 }
 471
 472
 473 /*******************************************************************************
 474  *
 475  * FUNCTION:    AcpiNsFindIniMethods
 476  *
 477  * PARAMETERS:  ACPI_WALK_CALLBACK
 478  *
 479  * RETURN:      ACPI_STATUS
 480  *
 481  * DESCRIPTION: Called during namespace walk. Finds objects named _INI under
 482  *              device/processor/thermal objects, and marks the entire subtree
 483  *              with a SUBTREE_HAS_INI flag. This flag is used during the
 484  *              subsequent device initialization walk to avoid entire subtrees
 485  *              that do not contain an _INI.
 486  *
 487  ******************************************************************************/
 488
 489 static ACPI_STATUS
 490 AcpiNsFindIniMethods (
 491     ACPI_HANDLE             ObjHandle,
 492     UINT32                  NestingLevel,
 493     void                    *Context,
 494     void                    **ReturnValue)
 495 {
 496     ACPI_DEVICE_WALK_INFO   *Info = ACPI_CAST_PTR (ACPI_DEVICE_WALK_INFO, Context);
 497     ACPI_NAMESPACE_NODE     *Node;
 498     ACPI_NAMESPACE_NODE     *ParentNode;
 499
 500
 501     /* Keep count of device/processor/thermal objects */
 502
 503     Node = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, ObjHandle);
 504     if ((Node->Type == ACPI_TYPE_DEVICE)    ||
 505         (Node->Type == ACPI_TYPE_PROCESSOR) ||
 506         (Node->Type == ACPI_TYPE_THERMAL))
 507     {
 508         Info->DeviceCount++;
 509         return (AE_OK);
 510     }
 511
 512     /* We are only looking for methods named _INI */
 513
 514     if (!ACPI_COMPARE_NAME (Node->Name.Ascii, METHOD_NAME__INI))
 515     {
 516         return (AE_OK);
 517     }
 518
 519     /*
 520      * The only _INI methods that we care about are those that are
 521      * present under Device, Processor, and Thermal objects.
 522      */
 523     ParentNode = Node->Parent;
 524     switch (ParentNode->Type)
 525     {
 526     case ACPI_TYPE_DEVICE:
 527     case ACPI_TYPE_PROCESSOR:
 528     case ACPI_TYPE_THERMAL:
 529
 530         /* Mark parent and bubble up the INI present flag to the root */
 531
 532         while (ParentNode)
 533         {
 534             ParentNode->Flags |= ANOBJ_SUBTREE_HAS_INI;
 535             ParentNode = ParentNode->Parent;
 536         }
 537         break;
 538
 539     default:
 540         break;
 541     }
 542
 543     return (AE_OK);
 544 }
 545
 546
 547 /*******************************************************************************
 548  *
 549  * FUNCTION:    AcpiNsInitOneDevice
 550  *
 551  * PARAMETERS:  ACPI_WALK_CALLBACK
 552  *
 553  * RETURN:      ACPI_STATUS
 554  *
 555  * DESCRIPTION: This is called once per device soon after ACPI is enabled
 556  *              to initialize each device. It determines if the device is
 557  *              present, and if so, calls _INI.
 558  *
 559  ******************************************************************************/
 560
 561 static ACPI_STATUS
 562 AcpiNsInitOneDevice (
 563     ACPI_HANDLE             ObjHandle,
 564     UINT32                  NestingLevel,
 565     void                    *Context,
 566     void                    **ReturnValue)
 567 {
 568     ACPI_DEVICE_WALK_INFO   *WalkInfo = ACPI_CAST_PTR (ACPI_DEVICE_WALK_INFO, Context);
 569     ACPI_EVALUATE_INFO      *Info = WalkInfo->EvaluateInfo;
 570     UINT32                  Flags;
 571     ACPI_STATUS             Status;
 572     ACPI_NAMESPACE_NODE     *DeviceNode;
 573
 574
 575     ACPI_FUNCTION_TRACE (NsInitOneDevice);
 576
 577
 578     /* We are interested in Devices, Processors and ThermalZones only */
 579
 580     DeviceNode = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, ObjHandle);
 581     if ((DeviceNode->Type != ACPI_TYPE_DEVICE)    &&
 582         (DeviceNode->Type != ACPI_TYPE_PROCESSOR) &&
 583         (DeviceNode->Type != ACPI_TYPE_THERMAL))
 584     {
 585         return_ACPI_STATUS (AE_OK);
 586     }
 587
 588     /*
 589      * Because of an earlier namespace analysis, all subtrees that contain an
 590      * _INI method are tagged.
 591      *
 592      * If this device subtree does not contain any _INI methods, we
 593      * can exit now and stop traversing this entire subtree.
 594      */
 595     if (!(DeviceNode->Flags & ANOBJ_SUBTREE_HAS_INI))
 596     {
 597         return_ACPI_STATUS (AE_CTRL_DEPTH);
 598     }
 599
 600     /*
 601      * Run _STA to determine if this device is present and functioning. We
 602      * must know this information for two important reasons (from ACPI spec):
 603      *
 604      * 1) We can only run _INI if the device is present.
 605      * 2) We must abort the device tree walk on this subtree if the device is
 606      *    not present and is not functional (we will not examine the children)
 607      *
 608      * The _STA method is not required to be present under the device, we
 609      * assume the device is present if _STA does not exist.
 610      */
 611     ACPI_DEBUG_EXEC (AcpiUtDisplayInitPathname (
 612         ACPI_TYPE_METHOD, DeviceNode, METHOD_NAME__STA));
 613
 614     Status = AcpiUtExecute_STA (DeviceNode, &Flags);
 615     if (ACPI_FAILURE (Status))
 616     {
 617         /* Ignore error and move on to next device */
 618
 619         return_ACPI_STATUS (AE_OK);
 620     }
 621
 622     /*
 623      * Flags == -1 means that _STA was not found. In this case, we assume that
 624      * the device is both present and functional.
 625      *
 626      * From the ACPI spec, description of _STA:
 627      *
 628      * "If a device object (including the processor object) does not have an
 629      * _STA object, then OSPM assumes that all of the above bits are set (in
 630      * other words, the device is present, ..., and functioning)"
 631      */
 632     if (Flags != ACPI_UINT32_MAX)
 633     {
 634         WalkInfo->Num_STA++;
 635     }
 636
 637     /*
 638      * Examine the PRESENT and FUNCTIONING status bits
 639      *
 640      * Note: ACPI spec does not seem to specify behavior for the present but
 641      * not functioning case, so we assume functioning if present.
 642      */
 643     if (!(Flags & ACPI_STA_DEVICE_PRESENT))
 644     {
 645         /* Device is not present, we must examine the Functioning bit */
 646
 647         if (Flags & ACPI_STA_DEVICE_FUNCTIONING)
 648         {
 649             /*
 650              * Device is not present but is "functioning". In this case,
 651              * we will not run _INI, but we continue to examine the children
 652              * of this device.
 653              *
 654              * From the ACPI spec, description of _STA: (Note - no mention
 655              * of whether to run _INI or not on the device in question)
 656              *
 657              * "_STA may return bit 0 clear (not present) with bit 3 set
 658              * (device is functional). This case is used to indicate a valid
 659              * device for which no device driver should be loaded (for example,
 660              * a bridge device.) Children of this device may be present and
 661              * valid. OSPM should continue enumeration below a device whose
 662              * _STA returns this bit combination"
 663              */
 664             return_ACPI_STATUS (AE_OK);
 665         }
 666         else
 667         {
 668             /*
 669              * Device is not present and is not functioning. We must abort the
 670              * walk of this subtree immediately -- don't look at the children
 671              * of such a device.
 672              *
 673              * From the ACPI spec, description of _INI:
 674              *
 675              * "If the _STA method indicates that the device is not present,
 676              * OSPM will not run the _INI and will not examine the children
 677              * of the device for _INI methods"
 678              */
 679             return_ACPI_STATUS (AE_CTRL_DEPTH);
 680         }
 681     }
 682
 683     /*
 684      * The device is present or is assumed present if no _STA exists.
 685      * Run the _INI if it exists (not required to exist)
 686      *
 687      * Note: We know there is an _INI within this subtree, but it may not be
 688      * under this particular device, it may be lower in the branch.
 689      */
 690     ACPI_DEBUG_EXEC (AcpiUtDisplayInitPathname (
 691         ACPI_TYPE_METHOD, DeviceNode, METHOD_NAME__INI));
 692
 693     Info->PrefixNode = DeviceNode;
 694     Info->Pathname = METHOD_NAME__INI;
 695     Info->Parameters = NULL;
 696     Info->Flags = ACPI_IGNORE_RETURN_VALUE;
 697
 698     Status = AcpiNsEvaluate (Info);
 699     if (ACPI_SUCCESS (Status))
 700     {
 701         WalkInfo->Num_INI++;
 702
 703         if ((AcpiDbgLevel <= ACPI_LV_ALL_EXCEPTIONS) &&
 704             (!(AcpiDbgLevel & ACPI_LV_INFO)))
 705         {
 706             ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INIT, "."));
 707         }
 708     }
 709
 710 #ifdef ACPI_DEBUG_OUTPUT
 711     else if (Status != AE_NOT_FOUND)
 712     {
 713         /* Ignore error and move on to next device */
 714
 715         char *ScopeName = AcpiNsGetExternalPathname (Info->ResolvedNode);
 716
 717         ACPI_EXCEPTION ((AE_INFO, Status, "during %s._INI execution",
 718             ScopeName));
 719         ACPI_FREE (ScopeName);
 720     }
 721 #endif
 722
 723     /* Ignore errors from above */
 724
 725     Status = AE_OK;
 726
 727     /*
 728      * The _INI method has been run if present; call the Global Initialization
 729      * Handler for this device.
 730      */
 731     if (AcpiGbl_InitHandler)
 732     {
 733         Status = AcpiGbl_InitHandler (DeviceNode, ACPI_INIT_DEVICE_INI);
 734     }
 735
 736     return_ACPI_STATUS (Status);
 737 }