xref: /haiku/src/add-ons/kernel/bus_managers/acpi/acpica/components/namespace/nsinit.c (revision e6eaad8615c4734498b9b800847d18bbe62782fa)
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 - 2013, 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:\n"));
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         "    Initialized %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         "and executing _INI/_STA methods:\n"));
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->RelativePathname = 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         "    Executed %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 
372         Info->OpRegionCount++;
373         break;
374 
375     case ACPI_TYPE_BUFFER_FIELD:
376 
377         Info->FieldCount++;
378         break;
379 
380     case ACPI_TYPE_LOCAL_BANK_FIELD:
381 
382         Info->FieldCount++;
383         break;
384 
385     case ACPI_TYPE_BUFFER:
386 
387         Info->BufferCount++;
388         break;
389 
390     case ACPI_TYPE_PACKAGE:
391 
392         Info->PackageCount++;
393         break;
394 
395     default:
396 
397         /* No init required, just exit now */
398 
399         return (AE_OK);
400     }
401 
402     /* If the object is already initialized, nothing else to do */
403 
404     if (ObjDesc->Common.Flags & AOPOBJ_DATA_VALID)
405     {
406         return (AE_OK);
407     }
408 
409     /* Must lock the interpreter before executing AML code */
410 
411     AcpiExEnterInterpreter ();
412 
413     /*
414      * Each of these types can contain executable AML code within the
415      * declaration.
416      */
417     switch (Type)
418     {
419     case ACPI_TYPE_REGION:
420 
421         Info->OpRegionInit++;
422         Status = AcpiDsGetRegionArguments (ObjDesc);
423         break;
424 
425     case ACPI_TYPE_BUFFER_FIELD:
426 
427         Info->FieldInit++;
428         Status = AcpiDsGetBufferFieldArguments (ObjDesc);
429         break;
430 
431     case ACPI_TYPE_LOCAL_BANK_FIELD:
432 
433         Info->FieldInit++;
434         Status = AcpiDsGetBankFieldArguments (ObjDesc);
435         break;
436 
437     case ACPI_TYPE_BUFFER:
438 
439         Info->BufferInit++;
440         Status = AcpiDsGetBufferArguments (ObjDesc);
441         break;
442 
443     case ACPI_TYPE_PACKAGE:
444 
445         Info->PackageInit++;
446         Status = AcpiDsGetPackageArguments (ObjDesc);
447         break;
448 
449     default:
450 
451         /* No other types can get here */
452 
453         break;
454     }
455 
456     if (ACPI_FAILURE (Status))
457     {
458         ACPI_EXCEPTION ((AE_INFO, Status,
459             "Could not execute arguments for [%4.4s] (%s)",
460             AcpiUtGetNodeName (Node), AcpiUtGetTypeName (Type)));
461     }
462 
463     /*
464      * We ignore errors from above, and always return OK, since we don't want
465      * to abort the walk on any single error.
466      */
467     AcpiExExitInterpreter ();
468     return (AE_OK);
469 }
470 
471 
472 /*******************************************************************************
473  *
474  * FUNCTION:    AcpiNsFindIniMethods
475  *
476  * PARAMETERS:  ACPI_WALK_CALLBACK
477  *
478  * RETURN:      ACPI_STATUS
479  *
480  * DESCRIPTION: Called during namespace walk. Finds objects named _INI under
481  *              device/processor/thermal objects, and marks the entire subtree
482  *              with a SUBTREE_HAS_INI flag. This flag is used during the
483  *              subsequent device initialization walk to avoid entire subtrees
484  *              that do not contain an _INI.
485  *
486  ******************************************************************************/
487 
488 static ACPI_STATUS
489 AcpiNsFindIniMethods (
490     ACPI_HANDLE             ObjHandle,
491     UINT32                  NestingLevel,
492     void                    *Context,
493     void                    **ReturnValue)
494 {
495     ACPI_DEVICE_WALK_INFO   *Info = ACPI_CAST_PTR (ACPI_DEVICE_WALK_INFO, Context);
496     ACPI_NAMESPACE_NODE     *Node;
497     ACPI_NAMESPACE_NODE     *ParentNode;
498 
499 
500     /* Keep count of device/processor/thermal objects */
501 
502     Node = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, ObjHandle);
503     if ((Node->Type == ACPI_TYPE_DEVICE)    ||
504         (Node->Type == ACPI_TYPE_PROCESSOR) ||
505         (Node->Type == ACPI_TYPE_THERMAL))
506     {
507         Info->DeviceCount++;
508         return (AE_OK);
509     }
510 
511     /* We are only looking for methods named _INI */
512 
513     if (!ACPI_COMPARE_NAME (Node->Name.Ascii, METHOD_NAME__INI))
514     {
515         return (AE_OK);
516     }
517 
518     /*
519      * The only _INI methods that we care about are those that are
520      * present under Device, Processor, and Thermal objects.
521      */
522     ParentNode = Node->Parent;
523     switch (ParentNode->Type)
524     {
525     case ACPI_TYPE_DEVICE:
526     case ACPI_TYPE_PROCESSOR:
527     case ACPI_TYPE_THERMAL:
528 
529         /* Mark parent and bubble up the INI present flag to the root */
530 
531         while (ParentNode)
532         {
533             ParentNode->Flags |= ANOBJ_SUBTREE_HAS_INI;
534             ParentNode = ParentNode->Parent;
535         }
536         break;
537 
538     default:
539 
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     ACPI_MEMSET (Info, 0, sizeof (ACPI_EVALUATE_INFO));
694     Info->PrefixNode = DeviceNode;
695     Info->RelativePathname = METHOD_NAME__INI;
696     Info->Parameters = NULL;
697     Info->Flags = ACPI_IGNORE_RETURN_VALUE;
698 
699     Status = AcpiNsEvaluate (Info);
700     if (ACPI_SUCCESS (Status))
701     {
702         WalkInfo->Num_INI++;
703     }
704 
705 #ifdef ACPI_DEBUG_OUTPUT
706     else if (Status != AE_NOT_FOUND)
707     {
708         /* Ignore error and move on to next device */
709 
710         char *ScopeName = AcpiNsGetExternalPathname (Info->Node);
711 
712         ACPI_EXCEPTION ((AE_INFO, Status, "during %s._INI execution",
713             ScopeName));
714         ACPI_FREE (ScopeName);
715     }
716 #endif
717 
718     /* Ignore errors from above */
719 
720     Status = AE_OK;
721 
722     /*
723      * The _INI method has been run if present; call the Global Initialization
724      * Handler for this device.
725      */
726     if (AcpiGbl_InitHandler)
727     {
728         Status = AcpiGbl_InitHandler (DeviceNode, ACPI_INIT_DEVICE_INI);
729     }
730 
731     return_ACPI_STATUS (Status);
732 }
733