xref: /titanic_52/usr/src/uts/intel/io/acpica/namespace/nsinit.c (revision ac88567a7a5bb7f01cf22cf366bc9d6203e24d7a)
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 - 2009, 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 %hd/%hd Regions %hd/%hd Fields %hd/%hd "
197         "Buffers %hd/%hd Packages (%hd 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         "%hd Control Methods found\n", Info.MethodCount));
205     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
206         "%hd 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     ACPI_FREE (Info.EvaluateInfo);
289     if (ACPI_FAILURE (Status))
290     {
291         goto ErrorExit;
292     }
293 
294     ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INIT,
295         "\nExecuted %hd _INI methods requiring %hd _STA executions "
296         "(examined %hd objects)\n",
297         Info.Num_INI, Info.Num_STA, Info.DeviceCount));
298 
299     return_ACPI_STATUS (Status);
300 
301 
302 ErrorExit:
303     ACPI_EXCEPTION ((AE_INFO, Status, "During device initialization"));
304     return_ACPI_STATUS (Status);
305 }
306 
307 
308 /*******************************************************************************
309  *
310  * FUNCTION:    AcpiNsInitOneObject
311  *
312  * PARAMETERS:  ObjHandle       - Node
313  *              Level           - Current nesting level
314  *              Context         - Points to a init info struct
315  *              ReturnValue     - Not used
316  *
317  * RETURN:      Status
318  *
319  * DESCRIPTION: Callback from AcpiWalkNamespace.  Invoked for every object
320  *              within the  namespace.
321  *
322  *              Currently, the only objects that require initialization are:
323  *              1) Methods
324  *              2) Op Regions
325  *
326  ******************************************************************************/
327 
328 static ACPI_STATUS
329 AcpiNsInitOneObject (
330     ACPI_HANDLE             ObjHandle,
331     UINT32                  Level,
332     void                    *Context,
333     void                    **ReturnValue)
334 {
335     ACPI_OBJECT_TYPE        Type;
336     ACPI_STATUS             Status = AE_OK;
337     ACPI_INIT_WALK_INFO     *Info = (ACPI_INIT_WALK_INFO *) Context;
338     ACPI_NAMESPACE_NODE     *Node = (ACPI_NAMESPACE_NODE *) ObjHandle;
339     ACPI_OPERAND_OBJECT     *ObjDesc;
340 
341 
342     ACPI_FUNCTION_NAME (NsInitOneObject);
343 
344 
345     Info->ObjectCount++;
346 
347     /* And even then, we are only interested in a few object types */
348 
349     Type = AcpiNsGetType (ObjHandle);
350     ObjDesc = AcpiNsGetAttachedObject (Node);
351     if (!ObjDesc)
352     {
353         return (AE_OK);
354     }
355 
356     /* Increment counters for object types we are looking for */
357 
358     switch (Type)
359     {
360     case ACPI_TYPE_REGION:
361         Info->OpRegionCount++;
362         break;
363 
364     case ACPI_TYPE_BUFFER_FIELD:
365         Info->FieldCount++;
366         break;
367 
368     case ACPI_TYPE_LOCAL_BANK_FIELD:
369         Info->FieldCount++;
370         break;
371 
372     case ACPI_TYPE_BUFFER:
373         Info->BufferCount++;
374         break;
375 
376     case ACPI_TYPE_PACKAGE:
377         Info->PackageCount++;
378         break;
379 
380     default:
381 
382         /* No init required, just exit now */
383         return (AE_OK);
384     }
385 
386     /* If the object is already initialized, nothing else to do */
387 
388     if (ObjDesc->Common.Flags & AOPOBJ_DATA_VALID)
389     {
390         return (AE_OK);
391     }
392 
393     /* Must lock the interpreter before executing AML code */
394 
395     AcpiExEnterInterpreter ();
396 
397     /*
398      * Each of these types can contain executable AML code within the
399      * declaration.
400      */
401     switch (Type)
402     {
403     case ACPI_TYPE_REGION:
404 
405         Info->OpRegionInit++;
406         Status = AcpiDsGetRegionArguments (ObjDesc);
407         break;
408 
409     case ACPI_TYPE_BUFFER_FIELD:
410 
411         Info->FieldInit++;
412         Status = AcpiDsGetBufferFieldArguments (ObjDesc);
413         break;
414 
415     case ACPI_TYPE_LOCAL_BANK_FIELD:
416 
417         Info->FieldInit++;
418         Status = AcpiDsGetBankFieldArguments (ObjDesc);
419         break;
420 
421     case ACPI_TYPE_BUFFER:
422 
423         Info->BufferInit++;
424         Status = AcpiDsGetBufferArguments (ObjDesc);
425         break;
426 
427     case ACPI_TYPE_PACKAGE:
428 
429         Info->PackageInit++;
430         Status = AcpiDsGetPackageArguments (ObjDesc);
431         break;
432 
433     default:
434         /* No other types can get here */
435         break;
436     }
437 
438     if (ACPI_FAILURE (Status))
439     {
440         ACPI_EXCEPTION ((AE_INFO, Status,
441             "Could not execute arguments for [%4.4s] (%s)",
442             AcpiUtGetNodeName (Node), AcpiUtGetTypeName (Type)));
443     }
444 
445     /*
446      * Print a dot for each object unless we are going to print the entire
447      * pathname
448      */
449     if (!(AcpiDbgLevel & ACPI_LV_INIT_NAMES))
450     {
451         ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INIT, "."));
452     }
453 
454     /*
455      * We ignore errors from above, and always return OK, since we don't want
456      * to abort the walk on any single error.
457      */
458     AcpiExExitInterpreter ();
459     return (AE_OK);
460 }
461 
462 
463 /*******************************************************************************
464  *
465  * FUNCTION:    AcpiNsFindIniMethods
466  *
467  * PARAMETERS:  ACPI_WALK_CALLBACK
468  *
469  * RETURN:      ACPI_STATUS
470  *
471  * DESCRIPTION: Called during namespace walk. Finds objects named _INI under
472  *              device/processor/thermal objects, and marks the entire subtree
473  *              with a SUBTREE_HAS_INI flag. This flag is used during the
474  *              subsequent device initialization walk to avoid entire subtrees
475  *              that do not contain an _INI.
476  *
477  ******************************************************************************/
478 
479 static ACPI_STATUS
480 AcpiNsFindIniMethods (
481     ACPI_HANDLE             ObjHandle,
482     UINT32                  NestingLevel,
483     void                    *Context,
484     void                    **ReturnValue)
485 {
486     ACPI_DEVICE_WALK_INFO   *Info = ACPI_CAST_PTR (ACPI_DEVICE_WALK_INFO, Context);
487     ACPI_NAMESPACE_NODE     *Node;
488     ACPI_NAMESPACE_NODE     *ParentNode;
489 
490 
491     /* Keep count of device/processor/thermal objects */
492 
493     Node = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, ObjHandle);
494     if ((Node->Type == ACPI_TYPE_DEVICE)    ||
495         (Node->Type == ACPI_TYPE_PROCESSOR) ||
496         (Node->Type == ACPI_TYPE_THERMAL))
497     {
498         Info->DeviceCount++;
499         return (AE_OK);
500     }
501 
502     /* We are only looking for methods named _INI */
503 
504     if (!ACPI_COMPARE_NAME (Node->Name.Ascii, METHOD_NAME__INI))
505     {
506         return (AE_OK);
507     }
508 
509     /*
510      * The only _INI methods that we care about are those that are
511      * present under Device, Processor, and Thermal objects.
512      */
513     ParentNode = AcpiNsGetParentNode (Node);
514     switch (ParentNode->Type)
515     {
516     case ACPI_TYPE_DEVICE:
517     case ACPI_TYPE_PROCESSOR:
518     case ACPI_TYPE_THERMAL:
519 
520         /* Mark parent and bubble up the INI present flag to the root */
521 
522         while (ParentNode)
523         {
524             ParentNode->Flags |= ANOBJ_SUBTREE_HAS_INI;
525             ParentNode = AcpiNsGetParentNode (ParentNode);
526         }
527         break;
528 
529     default:
530         break;
531     }
532 
533     return (AE_OK);
534 }
535 
536 
537 /*******************************************************************************
538  *
539  * FUNCTION:    AcpiNsInitOneDevice
540  *
541  * PARAMETERS:  ACPI_WALK_CALLBACK
542  *
543  * RETURN:      ACPI_STATUS
544  *
545  * DESCRIPTION: This is called once per device soon after ACPI is enabled
546  *              to initialize each device. It determines if the device is
547  *              present, and if so, calls _INI.
548  *
549  ******************************************************************************/
550 
551 static ACPI_STATUS
552 AcpiNsInitOneDevice (
553     ACPI_HANDLE             ObjHandle,
554     UINT32                  NestingLevel,
555     void                    *Context,
556     void                    **ReturnValue)
557 {
558     ACPI_DEVICE_WALK_INFO   *WalkInfo = ACPI_CAST_PTR (ACPI_DEVICE_WALK_INFO, Context);
559     ACPI_EVALUATE_INFO      *Info = WalkInfo->EvaluateInfo;
560     UINT32                  Flags;
561     ACPI_STATUS             Status;
562     ACPI_NAMESPACE_NODE     *DeviceNode;
563 
564 
565     ACPI_FUNCTION_TRACE (NsInitOneDevice);
566 
567 
568     /* We are interested in Devices, Processors and ThermalZones only */
569 
570     DeviceNode = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, ObjHandle);
571     if ((DeviceNode->Type != ACPI_TYPE_DEVICE)    &&
572         (DeviceNode->Type != ACPI_TYPE_PROCESSOR) &&
573         (DeviceNode->Type != ACPI_TYPE_THERMAL))
574     {
575         return_ACPI_STATUS (AE_OK);
576     }
577 
578     /*
579      * Because of an earlier namespace analysis, all subtrees that contain an
580      * _INI method are tagged.
581      *
582      * If this device subtree does not contain any _INI methods, we
583      * can exit now and stop traversing this entire subtree.
584      */
585     if (!(DeviceNode->Flags & ANOBJ_SUBTREE_HAS_INI))
586     {
587         return_ACPI_STATUS (AE_CTRL_DEPTH);
588     }
589 
590     /*
591      * Run _STA to determine if this device is present and functioning. We
592      * must know this information for two important reasons (from ACPI spec):
593      *
594      * 1) We can only run _INI if the device is present.
595      * 2) We must abort the device tree walk on this subtree if the device is
596      *    not present and is not functional (we will not examine the children)
597      *
598      * The _STA method is not required to be present under the device, we
599      * assume the device is present if _STA does not exist.
600      */
601     ACPI_DEBUG_EXEC (AcpiUtDisplayInitPathname (
602         ACPI_TYPE_METHOD, DeviceNode, METHOD_NAME__STA));
603 
604     Status = AcpiUtExecute_STA (DeviceNode, &Flags);
605     if (ACPI_FAILURE (Status))
606     {
607         /* Ignore error and move on to next device */
608 
609         return_ACPI_STATUS (AE_OK);
610     }
611 
612     /*
613      * Flags == -1 means that _STA was not found. In this case, we assume that
614      * the device is both present and functional.
615      *
616      * From the ACPI spec, description of _STA:
617      *
618      * "If a device object (including the processor object) does not have an
619      * _STA object, then OSPM assumes that all of the above bits are set (in
620      * other words, the device is present, ..., and functioning)"
621      */
622     if (Flags != ACPI_UINT32_MAX)
623     {
624         WalkInfo->Num_STA++;
625     }
626 
627     /*
628      * Examine the PRESENT and FUNCTIONING status bits
629      *
630      * Note: ACPI spec does not seem to specify behavior for the present but
631      * not functioning case, so we assume functioning if present.
632      */
633     if (!(Flags & ACPI_STA_DEVICE_PRESENT))
634     {
635         /* Device is not present, we must examine the Functioning bit */
636 
637         if (Flags & ACPI_STA_DEVICE_FUNCTIONING)
638         {
639             /*
640              * Device is not present but is "functioning". In this case,
641              * we will not run _INI, but we continue to examine the children
642              * of this device.
643              *
644              * From the ACPI spec, description of _STA: (Note - no mention
645              * of whether to run _INI or not on the device in question)
646              *
647              * "_STA may return bit 0 clear (not present) with bit 3 set
648              * (device is functional). This case is used to indicate a valid
649              * device for which no device driver should be loaded (for example,
650              * a bridge device.) Children of this device may be present and
651              * valid. OSPM should continue enumeration below a device whose
652              * _STA returns this bit combination"
653              */
654             return_ACPI_STATUS (AE_OK);
655         }
656         else
657         {
658             /*
659              * Device is not present and is not functioning. We must abort the
660              * walk of this subtree immediately -- don't look at the children
661              * of such a device.
662              *
663              * From the ACPI spec, description of _INI:
664              *
665              * "If the _STA method indicates that the device is not present,
666              * OSPM will not run the _INI and will not examine the children
667              * of the device for _INI methods"
668              */
669             return_ACPI_STATUS (AE_CTRL_DEPTH);
670         }
671     }
672 
673     /*
674      * The device is present or is assumed present if no _STA exists.
675      * Run the _INI if it exists (not required to exist)
676      *
677      * Note: We know there is an _INI within this subtree, but it may not be
678      * under this particular device, it may be lower in the branch.
679      */
680     ACPI_DEBUG_EXEC (AcpiUtDisplayInitPathname (
681         ACPI_TYPE_METHOD, DeviceNode, METHOD_NAME__INI));
682 
683     Info->PrefixNode = DeviceNode;
684     Info->Pathname = METHOD_NAME__INI;
685     Info->Parameters = NULL;
686     Info->Flags = ACPI_IGNORE_RETURN_VALUE;
687 
688     Status = AcpiNsEvaluate (Info);
689     if (ACPI_SUCCESS (Status))
690     {
691         WalkInfo->Num_INI++;
692 
693         if ((AcpiDbgLevel <= ACPI_LV_ALL_EXCEPTIONS) &&
694             (!(AcpiDbgLevel & ACPI_LV_INFO)))
695         {
696             ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INIT, "."));
697         }
698     }
699 
700 #ifdef ACPI_DEBUG_OUTPUT
701     else if (Status != AE_NOT_FOUND)
702     {
703         /* Ignore error and move on to next device */
704 
705         char *ScopeName = AcpiNsGetExternalPathname (Info->ResolvedNode);
706 
707         ACPI_EXCEPTION ((AE_INFO, Status, "during %s._INI execution",
708             ScopeName));
709         ACPI_FREE (ScopeName);
710     }
711 #endif
712 
713     /* Ignore errors from above */
714 
715     Status = AE_OK;
716 
717     /*
718      * The _INI method has been run if present; call the Global Initialization
719      * Handler for this device.
720      */
721     if (AcpiGbl_InitHandler)
722     {
723         Status = AcpiGbl_InitHandler (DeviceNode, ACPI_INIT_DEVICE_INI);
724     }
725 
726     return_ACPI_STATUS (Status);
727 }
728