xref: /titanic_41/usr/src/uts/intel/io/acpica/events/evrgnini.c (revision ea394cb00fd96864e34d2841b4a22357b621c78f)
1 /******************************************************************************
2  *
3  * Module Name: evrgnini- ACPI AddressSpace (OpRegion) init
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 __EVRGNINI_C__
118 
119 #include "acpi.h"
120 #include "accommon.h"
121 #include "acevents.h"
122 #include "acnamesp.h"
123 
124 #define _COMPONENT          ACPI_EVENTS
125         ACPI_MODULE_NAME    ("evrgnini")
126 
127 /* Local prototypes */
128 
129 static BOOLEAN
130 AcpiEvIsPciRootBridge (
131     ACPI_NAMESPACE_NODE     *Node);
132 
133 
134 /*******************************************************************************
135  *
136  * FUNCTION:    AcpiEvSystemMemoryRegionSetup
137  *
138  * PARAMETERS:  Handle              - Region we are interested in
139  *              Function            - Start or stop
140  *              HandlerContext      - Address space handler context
141  *              RegionContext       - Region specific context
142  *
143  * RETURN:      Status
144  *
145  * DESCRIPTION: Setup a SystemMemory operation region
146  *
147  ******************************************************************************/
148 
149 ACPI_STATUS
150 AcpiEvSystemMemoryRegionSetup (
151     ACPI_HANDLE             Handle,
152     UINT32                  Function,
153     void                    *HandlerContext,
154     void                    **RegionContext)
155 {
156     ACPI_OPERAND_OBJECT     *RegionDesc = (ACPI_OPERAND_OBJECT *) Handle;
157     ACPI_MEM_SPACE_CONTEXT  *LocalRegionContext;
158 
159 
160     ACPI_FUNCTION_TRACE (EvSystemMemoryRegionSetup);
161 
162 
163     if (Function == ACPI_REGION_DEACTIVATE)
164     {
165         if (*RegionContext)
166         {
167             LocalRegionContext = (ACPI_MEM_SPACE_CONTEXT *) *RegionContext;
168 
169             /* Delete a cached mapping if present */
170 
171             if (LocalRegionContext->MappedLength)
172             {
173                 AcpiOsUnmapMemory (LocalRegionContext->MappedLogicalAddress,
174                     LocalRegionContext->MappedLength);
175             }
176             ACPI_FREE (LocalRegionContext);
177             *RegionContext = NULL;
178         }
179         return_ACPI_STATUS (AE_OK);
180     }
181 
182     /* Create a new context */
183 
184     LocalRegionContext = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_MEM_SPACE_CONTEXT));
185     if (!(LocalRegionContext))
186     {
187         return_ACPI_STATUS (AE_NO_MEMORY);
188     }
189 
190     /* Save the region length and address for use in the handler */
191 
192     LocalRegionContext->Length  = RegionDesc->Region.Length;
193     LocalRegionContext->Address = RegionDesc->Region.Address;
194 
195     *RegionContext = LocalRegionContext;
196     return_ACPI_STATUS (AE_OK);
197 }
198 
199 
200 /*******************************************************************************
201  *
202  * FUNCTION:    AcpiEvIoSpaceRegionSetup
203  *
204  * PARAMETERS:  Handle              - Region we are interested in
205  *              Function            - Start or stop
206  *              HandlerContext      - Address space handler context
207  *              RegionContext       - Region specific context
208  *
209  * RETURN:      Status
210  *
211  * DESCRIPTION: Setup a IO operation region
212  *
213  ******************************************************************************/
214 
215 ACPI_STATUS
216 AcpiEvIoSpaceRegionSetup (
217     ACPI_HANDLE             Handle,
218     UINT32                  Function,
219     void                    *HandlerContext,
220     void                    **RegionContext)
221 {
222     ACPI_FUNCTION_TRACE (EvIoSpaceRegionSetup);
223 
224 
225     if (Function == ACPI_REGION_DEACTIVATE)
226     {
227         *RegionContext = NULL;
228     }
229     else
230     {
231         *RegionContext = HandlerContext;
232     }
233 
234     return_ACPI_STATUS (AE_OK);
235 }
236 
237 
238 /*******************************************************************************
239  *
240  * FUNCTION:    AcpiEvPciConfigRegionSetup
241  *
242  * PARAMETERS:  Handle              - Region we are interested in
243  *              Function            - Start or stop
244  *              HandlerContext      - Address space handler context
245  *              RegionContext       - Region specific context
246  *
247  * RETURN:      Status
248  *
249  * DESCRIPTION: Setup a PCI_Config operation region
250  *
251  * MUTEX:       Assumes namespace is not locked
252  *
253  ******************************************************************************/
254 
255 ACPI_STATUS
256 AcpiEvPciConfigRegionSetup (
257     ACPI_HANDLE             Handle,
258     UINT32                  Function,
259     void                    *HandlerContext,
260     void                    **RegionContext)
261 {
262     ACPI_STATUS             Status = AE_OK;
263     ACPI_INTEGER            PciValue;
264     ACPI_PCI_ID             *PciId = *RegionContext;
265     ACPI_OPERAND_OBJECT     *HandlerObj;
266     ACPI_NAMESPACE_NODE     *ParentNode;
267     ACPI_NAMESPACE_NODE     *PciRootNode;
268     ACPI_NAMESPACE_NODE     *PciDeviceNode;
269     ACPI_OPERAND_OBJECT     *RegionObj = (ACPI_OPERAND_OBJECT  *) Handle;
270 
271 
272     ACPI_FUNCTION_TRACE (EvPciConfigRegionSetup);
273 
274 
275     HandlerObj = RegionObj->Region.Handler;
276     if (!HandlerObj)
277     {
278         /*
279          * No installed handler. This shouldn't happen because the dispatch
280          * routine checks before we get here, but we check again just in case.
281          */
282         ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
283             "Attempting to init a region %p, with no handler\n", RegionObj));
284         return_ACPI_STATUS (AE_NOT_EXIST);
285     }
286 
287     *RegionContext = NULL;
288     if (Function == ACPI_REGION_DEACTIVATE)
289     {
290         if (PciId)
291         {
292             ACPI_FREE (PciId);
293         }
294         return_ACPI_STATUS (Status);
295     }
296 
297     ParentNode = AcpiNsGetParentNode (RegionObj->Region.Node);
298 
299     /*
300      * Get the _SEG and _BBN values from the device upon which the handler
301      * is installed.
302      *
303      * We need to get the _SEG and _BBN objects relative to the PCI BUS device.
304      * This is the device the handler has been registered to handle.
305      */
306 
307     /*
308      * If the AddressSpace.Node is still pointing to the root, we need
309      * to scan upward for a PCI Root bridge and re-associate the OpRegion
310      * handlers with that device.
311      */
312     if (HandlerObj->AddressSpace.Node == AcpiGbl_RootNode)
313     {
314         /* Start search from the parent object */
315 
316         PciRootNode = ParentNode;
317         while (PciRootNode != AcpiGbl_RootNode)
318         {
319             /* Get the _HID/_CID in order to detect a RootBridge */
320 
321             if (AcpiEvIsPciRootBridge (PciRootNode))
322             {
323                 /* Install a handler for this PCI root bridge */
324 
325                 Status = AcpiInstallAddressSpaceHandler (
326                             (ACPI_HANDLE) PciRootNode,
327                             ACPI_ADR_SPACE_PCI_CONFIG,
328                             ACPI_DEFAULT_HANDLER, NULL, NULL);
329                 if (ACPI_FAILURE (Status))
330                 {
331                     if (Status == AE_SAME_HANDLER)
332                     {
333                         /*
334                          * It is OK if the handler is already installed on the
335                          * root bridge. Still need to return a context object
336                          * for the new PCI_Config operation region, however.
337                          */
338                         Status = AE_OK;
339                     }
340                     else
341                     {
342                         ACPI_EXCEPTION ((AE_INFO, Status,
343                             "Could not install PciConfig handler "
344                             "for Root Bridge %4.4s",
345                             AcpiUtGetNodeName (PciRootNode)));
346                     }
347                 }
348                 break;
349             }
350 
351             PciRootNode = AcpiNsGetParentNode (PciRootNode);
352         }
353 
354         /* PCI root bridge not found, use namespace root node */
355     }
356     else
357     {
358         PciRootNode = HandlerObj->AddressSpace.Node;
359     }
360 
361     /*
362      * If this region is now initialized, we are done.
363      * (InstallAddressSpaceHandler could have initialized it)
364      */
365     if (RegionObj->Region.Flags & AOPOBJ_SETUP_COMPLETE)
366     {
367         return_ACPI_STATUS (AE_OK);
368     }
369 
370     /* Region is still not initialized. Create a new context */
371 
372     PciId = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_PCI_ID));
373     if (!PciId)
374     {
375         return_ACPI_STATUS (AE_NO_MEMORY);
376     }
377 
378     /*
379      * For PCI_Config space access, we need the segment, bus, device and
380      * function numbers. Acquire them here.
381      *
382      * Find the parent device object. (This allows the operation region to be
383      * within a subscope under the device, such as a control method.)
384      */
385     PciDeviceNode = RegionObj->Region.Node;
386     while (PciDeviceNode && (PciDeviceNode->Type != ACPI_TYPE_DEVICE))
387     {
388         PciDeviceNode = AcpiNsGetParentNode (PciDeviceNode);
389     }
390 
391     if (!PciDeviceNode)
392     {
393         ACPI_FREE (PciId);
394         return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
395     }
396 
397     /*
398      * Get the PCI device and function numbers from the _ADR object contained
399      * in the parent's scope.
400      */
401     Status = AcpiUtEvaluateNumericObject (METHOD_NAME__ADR,
402                 PciDeviceNode, &PciValue);
403 
404     /*
405      * The default is zero, and since the allocation above zeroed the data,
406      * just do nothing on failure.
407      */
408     if (ACPI_SUCCESS (Status))
409     {
410         PciId->Device   = ACPI_HIWORD (ACPI_LODWORD (PciValue));
411         PciId->Function = ACPI_LOWORD (ACPI_LODWORD (PciValue));
412     }
413 
414     /* The PCI segment number comes from the _SEG method */
415 
416     Status = AcpiUtEvaluateNumericObject (METHOD_NAME__SEG,
417                 PciRootNode, &PciValue);
418     if (ACPI_SUCCESS (Status))
419     {
420         PciId->Segment = ACPI_LOWORD (PciValue);
421     }
422 
423     /* The PCI bus number comes from the _BBN method */
424 
425     Status = AcpiUtEvaluateNumericObject (METHOD_NAME__BBN,
426                 PciRootNode, &PciValue);
427     if (ACPI_SUCCESS (Status))
428     {
429         PciId->Bus = ACPI_LOWORD (PciValue);
430     }
431 
432     /* Complete this device's PciId */
433 
434     AcpiOsDerivePciId (PciRootNode, RegionObj->Region.Node, &PciId);
435 
436     *RegionContext = PciId;
437     return_ACPI_STATUS (AE_OK);
438 }
439 
440 
441 /*******************************************************************************
442  *
443  * FUNCTION:    AcpiEvIsPciRootBridge
444  *
445  * PARAMETERS:  Node            - Device node being examined
446  *
447  * RETURN:      TRUE if device is a PCI/PCI-Express Root Bridge
448  *
449  * DESCRIPTION: Determine if the input device represents a PCI Root Bridge by
450  *              examining the _HID and _CID for the device.
451  *
452  ******************************************************************************/
453 
454 static BOOLEAN
455 AcpiEvIsPciRootBridge (
456     ACPI_NAMESPACE_NODE     *Node)
457 {
458     ACPI_STATUS             Status;
459     ACPI_DEVICE_ID          *Hid;
460     ACPI_DEVICE_ID_LIST     *Cid;
461     UINT32                  i;
462     BOOLEAN                 Match;
463 
464 
465     /* Get the _HID and check for a PCI Root Bridge */
466 
467     Status = AcpiUtExecute_HID (Node, &Hid);
468     if (ACPI_FAILURE (Status))
469     {
470         return (FALSE);
471     }
472 
473     Match = AcpiUtIsPciRootBridge (Hid->String);
474     ACPI_FREE (Hid);
475 
476     if (Match)
477     {
478         return (TRUE);
479     }
480 
481     /* The _HID did not match. Get the _CID and check for a PCI Root Bridge */
482 
483     Status = AcpiUtExecute_CID (Node, &Cid);
484     if (ACPI_FAILURE (Status))
485     {
486         return (FALSE);
487     }
488 
489     /* Check all _CIDs in the returned list */
490 
491     for (i = 0; i < Cid->Count; i++)
492     {
493         if (AcpiUtIsPciRootBridge (Cid->Ids[i].String))
494         {
495             ACPI_FREE (Cid);
496             return (TRUE);
497         }
498     }
499 
500     ACPI_FREE (Cid);
501     return (FALSE);
502 }
503 
504 
505 /*******************************************************************************
506  *
507  * FUNCTION:    AcpiEvPciBarRegionSetup
508  *
509  * PARAMETERS:  Handle              - Region we are interested in
510  *              Function            - Start or stop
511  *              HandlerContext      - Address space handler context
512  *              RegionContext       - Region specific context
513  *
514  * RETURN:      Status
515  *
516  * DESCRIPTION: Setup a PciBAR operation region
517  *
518  * MUTEX:       Assumes namespace is not locked
519  *
520  ******************************************************************************/
521 
522 ACPI_STATUS
523 AcpiEvPciBarRegionSetup (
524     ACPI_HANDLE             Handle,
525     UINT32                  Function,
526     void                    *HandlerContext,
527     void                    **RegionContext)
528 {
529     ACPI_FUNCTION_TRACE (EvPciBarRegionSetup);
530 
531 
532     return_ACPI_STATUS (AE_OK);
533 }
534 
535 
536 /*******************************************************************************
537  *
538  * FUNCTION:    AcpiEvCmosRegionSetup
539  *
540  * PARAMETERS:  Handle              - Region we are interested in
541  *              Function            - Start or stop
542  *              HandlerContext      - Address space handler context
543  *              RegionContext       - Region specific context
544  *
545  * RETURN:      Status
546  *
547  * DESCRIPTION: Setup a CMOS operation region
548  *
549  * MUTEX:       Assumes namespace is not locked
550  *
551  ******************************************************************************/
552 
553 ACPI_STATUS
554 AcpiEvCmosRegionSetup (
555     ACPI_HANDLE             Handle,
556     UINT32                  Function,
557     void                    *HandlerContext,
558     void                    **RegionContext)
559 {
560     ACPI_FUNCTION_TRACE (EvCmosRegionSetup);
561 
562 
563     return_ACPI_STATUS (AE_OK);
564 }
565 
566 
567 /*******************************************************************************
568  *
569  * FUNCTION:    AcpiEvDefaultRegionSetup
570  *
571  * PARAMETERS:  Handle              - Region we are interested in
572  *              Function            - Start or stop
573  *              HandlerContext      - Address space handler context
574  *              RegionContext       - Region specific context
575  *
576  * RETURN:      Status
577  *
578  * DESCRIPTION: Default region initialization
579  *
580  ******************************************************************************/
581 
582 ACPI_STATUS
583 AcpiEvDefaultRegionSetup (
584     ACPI_HANDLE             Handle,
585     UINT32                  Function,
586     void                    *HandlerContext,
587     void                    **RegionContext)
588 {
589     ACPI_FUNCTION_TRACE (EvDefaultRegionSetup);
590 
591 
592     if (Function == ACPI_REGION_DEACTIVATE)
593     {
594         *RegionContext = NULL;
595     }
596     else
597     {
598         *RegionContext = HandlerContext;
599     }
600 
601     return_ACPI_STATUS (AE_OK);
602 }
603 
604 
605 /*******************************************************************************
606  *
607  * FUNCTION:    AcpiEvInitializeRegion
608  *
609  * PARAMETERS:  RegionObj       - Region we are initializing
610  *              AcpiNsLocked    - Is namespace locked?
611  *
612  * RETURN:      Status
613  *
614  * DESCRIPTION: Initializes the region, finds any _REG methods and saves them
615  *              for execution at a later time
616  *
617  *              Get the appropriate address space handler for a newly
618  *              created region.
619  *
620  *              This also performs address space specific initialization. For
621  *              example, PCI regions must have an _ADR object that contains
622  *              a PCI address in the scope of the definition. This address is
623  *              required to perform an access to PCI config space.
624  *
625  * MUTEX:       Interpreter should be unlocked, because we may run the _REG
626  *              method for this region.
627  *
628  ******************************************************************************/
629 
630 ACPI_STATUS
631 AcpiEvInitializeRegion (
632     ACPI_OPERAND_OBJECT     *RegionObj,
633     BOOLEAN                 AcpiNsLocked)
634 {
635     ACPI_OPERAND_OBJECT     *HandlerObj;
636     ACPI_OPERAND_OBJECT     *ObjDesc;
637     ACPI_ADR_SPACE_TYPE     SpaceId;
638     ACPI_NAMESPACE_NODE     *Node;
639     ACPI_STATUS             Status;
640     ACPI_NAMESPACE_NODE     *MethodNode;
641     ACPI_NAME               *RegNamePtr = (ACPI_NAME *) METHOD_NAME__REG;
642     ACPI_OPERAND_OBJECT     *RegionObj2;
643 
644 
645     ACPI_FUNCTION_TRACE_U32 (EvInitializeRegion, AcpiNsLocked);
646 
647 
648     if (!RegionObj)
649     {
650         return_ACPI_STATUS (AE_BAD_PARAMETER);
651     }
652 
653     if (RegionObj->Common.Flags & AOPOBJ_OBJECT_INITIALIZED)
654     {
655         return_ACPI_STATUS (AE_OK);
656     }
657 
658     RegionObj2 = AcpiNsGetSecondaryObject (RegionObj);
659     if (!RegionObj2)
660     {
661         return_ACPI_STATUS (AE_NOT_EXIST);
662     }
663 
664     Node = AcpiNsGetParentNode (RegionObj->Region.Node);
665     SpaceId = RegionObj->Region.SpaceId;
666 
667     /* Setup defaults */
668 
669     RegionObj->Region.Handler = NULL;
670     RegionObj2->Extra.Method_REG = NULL;
671     RegionObj->Common.Flags &= ~(AOPOBJ_SETUP_COMPLETE);
672     RegionObj->Common.Flags |= AOPOBJ_OBJECT_INITIALIZED;
673 
674     /* Find any "_REG" method associated with this region definition */
675 
676     Status = AcpiNsSearchOneScope (
677                 *RegNamePtr, Node, ACPI_TYPE_METHOD, &MethodNode);
678     if (ACPI_SUCCESS (Status))
679     {
680         /*
681          * The _REG method is optional and there can be only one per region
682          * definition. This will be executed when the handler is attached
683          * or removed
684          */
685         RegionObj2->Extra.Method_REG = MethodNode;
686     }
687 
688     /*
689      * The following loop depends upon the root Node having no parent
690      * ie: AcpiGbl_RootNode->ParentEntry being set to NULL
691      */
692     while (Node)
693     {
694         /* Check to see if a handler exists */
695 
696         HandlerObj = NULL;
697         ObjDesc = AcpiNsGetAttachedObject (Node);
698         if (ObjDesc)
699         {
700             /* Can only be a handler if the object exists */
701 
702             switch (Node->Type)
703             {
704             case ACPI_TYPE_DEVICE:
705 
706                 HandlerObj = ObjDesc->Device.Handler;
707                 break;
708 
709             case ACPI_TYPE_PROCESSOR:
710 
711                 HandlerObj = ObjDesc->Processor.Handler;
712                 break;
713 
714             case ACPI_TYPE_THERMAL:
715 
716                 HandlerObj = ObjDesc->ThermalZone.Handler;
717                 break;
718 
719             default:
720                 /* Ignore other objects */
721                 break;
722             }
723 
724             while (HandlerObj)
725             {
726                 /* Is this handler of the correct type? */
727 
728                 if (HandlerObj->AddressSpace.SpaceId == SpaceId)
729                 {
730                     /* Found correct handler */
731 
732                     ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
733                         "Found handler %p for region %p in obj %p\n",
734                         HandlerObj, RegionObj, ObjDesc));
735 
736                     Status = AcpiEvAttachRegion (HandlerObj, RegionObj,
737                                 AcpiNsLocked);
738 
739                     /*
740                      * Tell all users that this region is usable by
741                      * running the _REG method
742                      */
743                     if (AcpiNsLocked)
744                     {
745                         Status = AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
746                         if (ACPI_FAILURE (Status))
747                         {
748                             return_ACPI_STATUS (Status);
749                         }
750                     }
751 
752                     Status = AcpiEvExecuteRegMethod (RegionObj, 1);
753 
754                     if (AcpiNsLocked)
755                     {
756                         Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
757                         if (ACPI_FAILURE (Status))
758                         {
759                             return_ACPI_STATUS (Status);
760                         }
761                     }
762 
763                     return_ACPI_STATUS (AE_OK);
764                 }
765 
766                 /* Try next handler in the list */
767 
768                 HandlerObj = HandlerObj->AddressSpace.Next;
769             }
770         }
771 
772         /* This node does not have the handler we need; Pop up one level */
773 
774         Node = AcpiNsGetParentNode (Node);
775     }
776 
777     /* If we get here, there is no handler for this region */
778 
779     ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
780         "No handler for RegionType %s(%X) (RegionObj %p)\n",
781         AcpiUtGetRegionName (SpaceId), SpaceId, RegionObj));
782 
783     return_ACPI_STATUS (AE_NOT_EXIST);
784 }
785 
786