xref: /titanic_50/usr/src/uts/intel/io/acpica/dispatcher/dswload2.c (revision 3fc1e28905f8d0b151f1f359d523492bed5a20f2)
1 /******************************************************************************
2  *
3  * Module Name: dswload2 - Dispatcher second pass namespace load callbacks
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2011, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #define __DSWLOAD2_C__
45 
46 #include "acpi.h"
47 #include "accommon.h"
48 #include "acparser.h"
49 #include "amlcode.h"
50 #include "acdispat.h"
51 #include "acinterp.h"
52 #include "acnamesp.h"
53 #include "acevents.h"
54 
55 #define _COMPONENT          ACPI_DISPATCHER
56         ACPI_MODULE_NAME    ("dswload2")
57 
58 
59 /*******************************************************************************
60  *
61  * FUNCTION:    AcpiDsLoad2BeginOp
62  *
63  * PARAMETERS:  WalkState       - Current state of the parse tree walk
64  *              OutOp           - Wher to return op if a new one is created
65  *
66  * RETURN:      Status
67  *
68  * DESCRIPTION: Descending callback used during the loading of ACPI tables.
69  *
70  ******************************************************************************/
71 
72 ACPI_STATUS
73 AcpiDsLoad2BeginOp (
74     ACPI_WALK_STATE         *WalkState,
75     ACPI_PARSE_OBJECT       **OutOp)
76 {
77     ACPI_PARSE_OBJECT       *Op;
78     ACPI_NAMESPACE_NODE     *Node;
79     ACPI_STATUS             Status;
80     ACPI_OBJECT_TYPE        ObjectType;
81     char                    *BufferPtr;
82     UINT32                  Flags;
83 
84 
85     ACPI_FUNCTION_TRACE (DsLoad2BeginOp);
86 
87 
88     Op = WalkState->Op;
89     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Op=%p State=%p\n", Op, WalkState));
90 
91     if (Op)
92     {
93         if ((WalkState->ControlState) &&
94             (WalkState->ControlState->Common.State ==
95                 ACPI_CONTROL_CONDITIONAL_EXECUTING))
96         {
97             /* We are executing a while loop outside of a method */
98 
99             Status = AcpiDsExecBeginOp (WalkState, OutOp);
100             return_ACPI_STATUS (Status);
101         }
102 
103         /* We only care about Namespace opcodes here */
104 
105         if ((!(WalkState->OpInfo->Flags & AML_NSOPCODE)   &&
106               (WalkState->Opcode != AML_INT_NAMEPATH_OP)) ||
107             (!(WalkState->OpInfo->Flags & AML_NAMED)))
108         {
109             return_ACPI_STATUS (AE_OK);
110         }
111 
112         /* Get the name we are going to enter or lookup in the namespace */
113 
114         if (WalkState->Opcode == AML_INT_NAMEPATH_OP)
115         {
116             /* For Namepath op, get the path string */
117 
118             BufferPtr = Op->Common.Value.String;
119             if (!BufferPtr)
120             {
121                 /* No name, just exit */
122 
123                 return_ACPI_STATUS (AE_OK);
124             }
125         }
126         else
127         {
128             /* Get name from the op */
129 
130             BufferPtr = ACPI_CAST_PTR (char, &Op->Named.Name);
131         }
132     }
133     else
134     {
135         /* Get the namestring from the raw AML */
136 
137         BufferPtr = AcpiPsGetNextNamestring (&WalkState->ParserState);
138     }
139 
140     /* Map the opcode into an internal object type */
141 
142     ObjectType = WalkState->OpInfo->ObjectType;
143 
144     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
145         "State=%p Op=%p Type=%X\n", WalkState, Op, ObjectType));
146 
147     switch (WalkState->Opcode)
148     {
149     case AML_FIELD_OP:
150     case AML_BANK_FIELD_OP:
151     case AML_INDEX_FIELD_OP:
152 
153         Node = NULL;
154         Status = AE_OK;
155         break;
156 
157     case AML_INT_NAMEPATH_OP:
158         /*
159          * The NamePath is an object reference to an existing object.
160          * Don't enter the name into the namespace, but look it up
161          * for use later.
162          */
163         Status = AcpiNsLookup (WalkState->ScopeInfo, BufferPtr, ObjectType,
164                         ACPI_IMODE_EXECUTE, ACPI_NS_SEARCH_PARENT,
165                         WalkState, &(Node));
166         break;
167 
168     case AML_SCOPE_OP:
169 
170         /* Special case for Scope(\) -> refers to the Root node */
171 
172         if (Op && (Op->Named.Node == AcpiGbl_RootNode))
173         {
174             Node = Op->Named.Node;
175 
176             Status = AcpiDsScopeStackPush (Node, ObjectType, WalkState);
177             if (ACPI_FAILURE (Status))
178             {
179                 return_ACPI_STATUS (Status);
180             }
181         }
182         else
183         {
184             /*
185              * The Path is an object reference to an existing object.
186              * Don't enter the name into the namespace, but look it up
187              * for use later.
188              */
189             Status = AcpiNsLookup (WalkState->ScopeInfo, BufferPtr, ObjectType,
190                         ACPI_IMODE_EXECUTE, ACPI_NS_SEARCH_PARENT,
191                         WalkState, &(Node));
192             if (ACPI_FAILURE (Status))
193             {
194 #ifdef ACPI_ASL_COMPILER
195                 if (Status == AE_NOT_FOUND)
196                 {
197                     Status = AE_OK;
198                 }
199                 else
200                 {
201                     ACPI_ERROR_NAMESPACE (BufferPtr, Status);
202                 }
203 #else
204                 ACPI_ERROR_NAMESPACE (BufferPtr, Status);
205 #endif
206                 return_ACPI_STATUS (Status);
207             }
208         }
209 
210         /*
211          * We must check to make sure that the target is
212          * one of the opcodes that actually opens a scope
213          */
214         switch (Node->Type)
215         {
216         case ACPI_TYPE_ANY:
217         case ACPI_TYPE_LOCAL_SCOPE:         /* Scope */
218         case ACPI_TYPE_DEVICE:
219         case ACPI_TYPE_POWER:
220         case ACPI_TYPE_PROCESSOR:
221         case ACPI_TYPE_THERMAL:
222 
223             /* These are acceptable types */
224             break;
225 
226         case ACPI_TYPE_INTEGER:
227         case ACPI_TYPE_STRING:
228         case ACPI_TYPE_BUFFER:
229 
230             /*
231              * These types we will allow, but we will change the type.
232              * This enables some existing code of the form:
233              *
234              *  Name (DEB, 0)
235              *  Scope (DEB) { ... }
236              */
237             ACPI_WARNING ((AE_INFO,
238                 "Type override - [%4.4s] had invalid type (%s) "
239                 "for Scope operator, changed to type ANY\n",
240                 AcpiUtGetNodeName (Node), AcpiUtGetTypeName (Node->Type)));
241 
242             Node->Type = ACPI_TYPE_ANY;
243             WalkState->ScopeInfo->Common.Value = ACPI_TYPE_ANY;
244             break;
245 
246         default:
247 
248             /* All other types are an error */
249 
250             ACPI_ERROR ((AE_INFO,
251                 "Invalid type (%s) for target of "
252                 "Scope operator [%4.4s] (Cannot override)",
253                 AcpiUtGetTypeName (Node->Type), AcpiUtGetNodeName (Node)));
254 
255             return (AE_AML_OPERAND_TYPE);
256         }
257         break;
258 
259     default:
260 
261         /* All other opcodes */
262 
263         if (Op && Op->Common.Node)
264         {
265             /* This op/node was previously entered into the namespace */
266 
267             Node = Op->Common.Node;
268 
269             if (AcpiNsOpensScope (ObjectType))
270             {
271                 Status = AcpiDsScopeStackPush (Node, ObjectType, WalkState);
272                 if (ACPI_FAILURE (Status))
273                 {
274                     return_ACPI_STATUS (Status);
275                 }
276             }
277 
278             return_ACPI_STATUS (AE_OK);
279         }
280 
281         /*
282          * Enter the named type into the internal namespace. We enter the name
283          * as we go downward in the parse tree. Any necessary subobjects that
284          * involve arguments to the opcode must be created as we go back up the
285          * parse tree later.
286          *
287          * Note: Name may already exist if we are executing a deferred opcode.
288          */
289         if (WalkState->DeferredNode)
290         {
291             /* This name is already in the namespace, get the node */
292 
293             Node = WalkState->DeferredNode;
294             Status = AE_OK;
295             break;
296         }
297 
298         Flags = ACPI_NS_NO_UPSEARCH;
299         if (WalkState->PassNumber == ACPI_IMODE_EXECUTE)
300         {
301             /* Execution mode, node cannot already exist, node is temporary */
302 
303             Flags |= ACPI_NS_ERROR_IF_FOUND;
304 
305             if (!(WalkState->ParseFlags & ACPI_PARSE_MODULE_LEVEL))
306             {
307                 Flags |= ACPI_NS_TEMPORARY;
308             }
309         }
310 
311         /* Add new entry or lookup existing entry */
312 
313         Status = AcpiNsLookup (WalkState->ScopeInfo, BufferPtr, ObjectType,
314                     ACPI_IMODE_LOAD_PASS2, Flags, WalkState, &Node);
315 
316         if (ACPI_SUCCESS (Status) && (Flags & ACPI_NS_TEMPORARY))
317         {
318             ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
319                 "***New Node [%4.4s] %p is temporary\n",
320                 AcpiUtGetNodeName (Node), Node));
321         }
322         break;
323     }
324 
325     if (ACPI_FAILURE (Status))
326     {
327         ACPI_ERROR_NAMESPACE (BufferPtr, Status);
328         return_ACPI_STATUS (Status);
329     }
330 
331     if (!Op)
332     {
333         /* Create a new op */
334 
335         Op = AcpiPsAllocOp (WalkState->Opcode);
336         if (!Op)
337         {
338             return_ACPI_STATUS (AE_NO_MEMORY);
339         }
340 
341         /* Initialize the new op */
342 
343         if (Node)
344         {
345             Op->Named.Name = Node->Name.Integer;
346         }
347         *OutOp = Op;
348     }
349 
350     /*
351      * Put the Node in the "op" object that the parser uses, so we
352      * can get it again quickly when this scope is closed
353      */
354     Op->Common.Node = Node;
355     return_ACPI_STATUS (Status);
356 }
357 
358 
359 /*******************************************************************************
360  *
361  * FUNCTION:    AcpiDsLoad2EndOp
362  *
363  * PARAMETERS:  WalkState       - Current state of the parse tree walk
364  *
365  * RETURN:      Status
366  *
367  * DESCRIPTION: Ascending callback used during the loading of the namespace,
368  *              both control methods and everything else.
369  *
370  ******************************************************************************/
371 
372 ACPI_STATUS
373 AcpiDsLoad2EndOp (
374     ACPI_WALK_STATE         *WalkState)
375 {
376     ACPI_PARSE_OBJECT       *Op;
377     ACPI_STATUS             Status = AE_OK;
378     ACPI_OBJECT_TYPE        ObjectType;
379     ACPI_NAMESPACE_NODE     *Node;
380     ACPI_PARSE_OBJECT       *Arg;
381     ACPI_NAMESPACE_NODE     *NewNode;
382 #ifndef ACPI_NO_METHOD_EXECUTION
383     UINT32                  i;
384     UINT8                   RegionSpace;
385 #endif
386 
387 
388     ACPI_FUNCTION_TRACE (DsLoad2EndOp);
389 
390     Op = WalkState->Op;
391     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Opcode [%s] Op %p State %p\n",
392             WalkState->OpInfo->Name, Op, WalkState));
393 
394     /* Check if opcode had an associated namespace object */
395 
396     if (!(WalkState->OpInfo->Flags & AML_NSOBJECT))
397     {
398         return_ACPI_STATUS (AE_OK);
399     }
400 
401     if (Op->Common.AmlOpcode == AML_SCOPE_OP)
402     {
403         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
404             "Ending scope Op=%p State=%p\n", Op, WalkState));
405     }
406 
407     ObjectType = WalkState->OpInfo->ObjectType;
408 
409     /*
410      * Get the Node/name from the earlier lookup
411      * (It was saved in the *op structure)
412      */
413     Node = Op->Common.Node;
414 
415     /*
416      * Put the Node on the object stack (Contains the ACPI Name of
417      * this object)
418      */
419     WalkState->Operands[0] = (void *) Node;
420     WalkState->NumOperands = 1;
421 
422     /* Pop the scope stack */
423 
424     if (AcpiNsOpensScope (ObjectType) &&
425        (Op->Common.AmlOpcode != AML_INT_METHODCALL_OP))
426     {
427         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "(%s) Popping scope for Op %p\n",
428             AcpiUtGetTypeName (ObjectType), Op));
429 
430         Status = AcpiDsScopeStackPop (WalkState);
431         if (ACPI_FAILURE (Status))
432         {
433             goto Cleanup;
434         }
435     }
436 
437     /*
438      * Named operations are as follows:
439      *
440      * AML_ALIAS
441      * AML_BANKFIELD
442      * AML_CREATEBITFIELD
443      * AML_CREATEBYTEFIELD
444      * AML_CREATEDWORDFIELD
445      * AML_CREATEFIELD
446      * AML_CREATEQWORDFIELD
447      * AML_CREATEWORDFIELD
448      * AML_DATA_REGION
449      * AML_DEVICE
450      * AML_EVENT
451      * AML_FIELD
452      * AML_INDEXFIELD
453      * AML_METHOD
454      * AML_METHODCALL
455      * AML_MUTEX
456      * AML_NAME
457      * AML_NAMEDFIELD
458      * AML_OPREGION
459      * AML_POWERRES
460      * AML_PROCESSOR
461      * AML_SCOPE
462      * AML_THERMALZONE
463      */
464 
465     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
466         "Create-Load [%s] State=%p Op=%p NamedObj=%p\n",
467         AcpiPsGetOpcodeName (Op->Common.AmlOpcode), WalkState, Op, Node));
468 
469     /* Decode the opcode */
470 
471     Arg = Op->Common.Value.Arg;
472 
473     switch (WalkState->OpInfo->Type)
474     {
475 #ifndef ACPI_NO_METHOD_EXECUTION
476 
477     case AML_TYPE_CREATE_FIELD:
478         /*
479          * Create the field object, but the field buffer and index must
480          * be evaluated later during the execution phase
481          */
482         Status = AcpiDsCreateBufferField (Op, WalkState);
483         break;
484 
485 
486      case AML_TYPE_NAMED_FIELD:
487         /*
488          * If we are executing a method, initialize the field
489          */
490         if (WalkState->MethodNode)
491         {
492             Status = AcpiDsInitFieldObjects (Op, WalkState);
493         }
494 
495         switch (Op->Common.AmlOpcode)
496         {
497         case AML_INDEX_FIELD_OP:
498 
499             Status = AcpiDsCreateIndexField (Op, (ACPI_HANDLE) Arg->Common.Node,
500                         WalkState);
501             break;
502 
503         case AML_BANK_FIELD_OP:
504 
505             Status = AcpiDsCreateBankField (Op, Arg->Common.Node, WalkState);
506             break;
507 
508         case AML_FIELD_OP:
509 
510             Status = AcpiDsCreateField (Op, Arg->Common.Node, WalkState);
511             break;
512 
513         default:
514             /* All NAMED_FIELD opcodes must be handled above */
515             break;
516         }
517         break;
518 
519 
520      case AML_TYPE_NAMED_SIMPLE:
521 
522         Status = AcpiDsCreateOperands (WalkState, Arg);
523         if (ACPI_FAILURE (Status))
524         {
525             goto Cleanup;
526         }
527 
528         switch (Op->Common.AmlOpcode)
529         {
530         case AML_PROCESSOR_OP:
531 
532             Status = AcpiExCreateProcessor (WalkState);
533             break;
534 
535         case AML_POWER_RES_OP:
536 
537             Status = AcpiExCreatePowerResource (WalkState);
538             break;
539 
540         case AML_MUTEX_OP:
541 
542             Status = AcpiExCreateMutex (WalkState);
543             break;
544 
545         case AML_EVENT_OP:
546 
547             Status = AcpiExCreateEvent (WalkState);
548             break;
549 
550 
551         case AML_ALIAS_OP:
552 
553             Status = AcpiExCreateAlias (WalkState);
554             break;
555 
556         default:
557             /* Unknown opcode */
558 
559             Status = AE_OK;
560             goto Cleanup;
561         }
562 
563         /* Delete operands */
564 
565         for (i = 1; i < WalkState->NumOperands; i++)
566         {
567             AcpiUtRemoveReference (WalkState->Operands[i]);
568             WalkState->Operands[i] = NULL;
569         }
570 
571         break;
572 #endif /* ACPI_NO_METHOD_EXECUTION */
573 
574     case AML_TYPE_NAMED_COMPLEX:
575 
576         switch (Op->Common.AmlOpcode)
577         {
578 #ifndef ACPI_NO_METHOD_EXECUTION
579         case AML_REGION_OP:
580         case AML_DATA_REGION_OP:
581 
582             if (Op->Common.AmlOpcode == AML_REGION_OP)
583             {
584                 RegionSpace = (ACPI_ADR_SPACE_TYPE)
585                       ((Op->Common.Value.Arg)->Common.Value.Integer);
586             }
587             else
588             {
589                 RegionSpace = ACPI_ADR_SPACE_DATA_TABLE;
590             }
591 
592             /*
593              * The OpRegion is not fully parsed at this time. The only valid
594              * argument is the SpaceId. (We must save the address of the
595              * AML of the address and length operands)
596              *
597              * If we have a valid region, initialize it. The namespace is
598              * unlocked at this point.
599              *
600              * Need to unlock interpreter if it is locked (if we are running
601              * a control method), in order to allow _REG methods to be run
602              * during AcpiEvInitializeRegion.
603              */
604             if (WalkState->MethodNode)
605             {
606                 /*
607                  * Executing a method: initialize the region and unlock
608                  * the interpreter
609                  */
610                 Status = AcpiExCreateRegion (Op->Named.Data, Op->Named.Length,
611                             RegionSpace, WalkState);
612                 if (ACPI_FAILURE (Status))
613                 {
614                     return (Status);
615                 }
616 
617                 AcpiExExitInterpreter ();
618             }
619 
620             Status = AcpiEvInitializeRegion (AcpiNsGetAttachedObject (Node),
621                         FALSE);
622             if (WalkState->MethodNode)
623             {
624                 AcpiExEnterInterpreter ();
625             }
626 
627             if (ACPI_FAILURE (Status))
628             {
629                 /*
630                  *  If AE_NOT_EXIST is returned, it is not fatal
631                  *  because many regions get created before a handler
632                  *  is installed for said region.
633                  */
634                 if (AE_NOT_EXIST == Status)
635                 {
636                     Status = AE_OK;
637                 }
638             }
639             break;
640 
641 
642         case AML_NAME_OP:
643 
644             Status = AcpiDsCreateNode (WalkState, Node, Op);
645             break;
646 
647 
648         case AML_METHOD_OP:
649             /*
650              * MethodOp PkgLength NameString MethodFlags TermList
651              *
652              * Note: We must create the method node/object pair as soon as we
653              * see the method declaration. This allows later pass1 parsing
654              * of invocations of the method (need to know the number of
655              * arguments.)
656              */
657             ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
658                 "LOADING-Method: State=%p Op=%p NamedObj=%p\n",
659                 WalkState, Op, Op->Named.Node));
660 
661             if (!AcpiNsGetAttachedObject (Op->Named.Node))
662             {
663                 WalkState->Operands[0] = ACPI_CAST_PTR (void, Op->Named.Node);
664                 WalkState->NumOperands = 1;
665 
666                 Status = AcpiDsCreateOperands (WalkState, Op->Common.Value.Arg);
667                 if (ACPI_SUCCESS (Status))
668                 {
669                     Status = AcpiExCreateMethod (Op->Named.Data,
670                                         Op->Named.Length, WalkState);
671                 }
672                 WalkState->Operands[0] = NULL;
673                 WalkState->NumOperands = 0;
674 
675                 if (ACPI_FAILURE (Status))
676                 {
677                     return_ACPI_STATUS (Status);
678                 }
679             }
680             break;
681 
682 #endif /* ACPI_NO_METHOD_EXECUTION */
683 
684         default:
685             /* All NAMED_COMPLEX opcodes must be handled above */
686             break;
687         }
688         break;
689 
690 
691     case AML_CLASS_INTERNAL:
692 
693         /* case AML_INT_NAMEPATH_OP: */
694         break;
695 
696 
697     case AML_CLASS_METHOD_CALL:
698 
699         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
700             "RESOLVING-MethodCall: State=%p Op=%p NamedObj=%p\n",
701             WalkState, Op, Node));
702 
703         /*
704          * Lookup the method name and save the Node
705          */
706         Status = AcpiNsLookup (WalkState->ScopeInfo, Arg->Common.Value.String,
707                         ACPI_TYPE_ANY, ACPI_IMODE_LOAD_PASS2,
708                         ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE,
709                         WalkState, &(NewNode));
710         if (ACPI_SUCCESS (Status))
711         {
712             /*
713              * Make sure that what we found is indeed a method
714              * We didn't search for a method on purpose, to see if the name
715              * would resolve
716              */
717             if (NewNode->Type != ACPI_TYPE_METHOD)
718             {
719                 Status = AE_AML_OPERAND_TYPE;
720             }
721 
722             /* We could put the returned object (Node) on the object stack for
723              * later, but for now, we will put it in the "op" object that the
724              * parser uses, so we can get it again at the end of this scope
725              */
726             Op->Common.Node = NewNode;
727         }
728         else
729         {
730             ACPI_ERROR_NAMESPACE (Arg->Common.Value.String, Status);
731         }
732         break;
733 
734 
735     default:
736         break;
737     }
738 
739 Cleanup:
740 
741     /* Remove the Node pushed at the very beginning */
742 
743     WalkState->Operands[0] = NULL;
744     WalkState->NumOperands = 0;
745     return_ACPI_STATUS (Status);
746 }
747 
748