xref: /titanic_51/usr/src/uts/intel/io/acpica/dispatcher/dswstate.c (revision a51287096c163d49f314be2853367563999e083c)
1 /******************************************************************************
2  *
3  * Module Name: dswstate - Dispatcher parse tree walk management routines
4  *              $Revision: 1.105 $
5  *
6  *****************************************************************************/
7 
8 /******************************************************************************
9  *
10  * 1. Copyright Notice
11  *
12  * Some or all of this work - Copyright (c) 1999 - 2008, Intel Corp.
13  * All rights reserved.
14  *
15  * 2. License
16  *
17  * 2.1. This is your license from Intel Corp. under its intellectual property
18  * rights.  You may have additional license terms from the party that provided
19  * you this software, covering your right to use that party's intellectual
20  * property rights.
21  *
22  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
23  * copy of the source code appearing in this file ("Covered Code") an
24  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
25  * base code distributed originally by Intel ("Original Intel Code") to copy,
26  * make derivatives, distribute, use and display any portion of the Covered
27  * Code in any form, with the right to sublicense such rights; and
28  *
29  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
30  * license (with the right to sublicense), under only those claims of Intel
31  * patents that are infringed by the Original Intel Code, to make, use, sell,
32  * offer to sell, and import the Covered Code and derivative works thereof
33  * solely to the minimum extent necessary to exercise the above copyright
34  * license, and in no event shall the patent license extend to any additions
35  * to or modifications of the Original Intel Code.  No other license or right
36  * is granted directly or by implication, estoppel or otherwise;
37  *
38  * The above copyright and patent license is granted only if the following
39  * conditions are met:
40  *
41  * 3. Conditions
42  *
43  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
44  * Redistribution of source code of any substantial portion of the Covered
45  * Code or modification with rights to further distribute source must include
46  * the above Copyright Notice, the above License, this list of Conditions,
47  * and the following Disclaimer and Export Compliance provision.  In addition,
48  * Licensee must cause all Covered Code to which Licensee contributes to
49  * contain a file documenting the changes Licensee made to create that Covered
50  * Code and the date of any change.  Licensee must include in that file the
51  * documentation of any changes made by any predecessor Licensee.  Licensee
52  * must include a prominent statement that the modification is derived,
53  * directly or indirectly, from Original Intel Code.
54  *
55  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
56  * Redistribution of source code of any substantial portion of the Covered
57  * Code or modification without rights to further distribute source must
58  * include the following Disclaimer and Export Compliance provision in the
59  * documentation and/or other materials provided with distribution.  In
60  * addition, Licensee may not authorize further sublicense of source of any
61  * portion of the Covered Code, and must include terms to the effect that the
62  * license from Licensee to its licensee is limited to the intellectual
63  * property embodied in the software Licensee provides to its licensee, and
64  * not to intellectual property embodied in modifications its licensee may
65  * make.
66  *
67  * 3.3. Redistribution of Executable. Redistribution in executable form of any
68  * substantial portion of the Covered Code or modification must reproduce the
69  * above Copyright Notice, and the following Disclaimer and Export Compliance
70  * provision in the documentation and/or other materials provided with the
71  * distribution.
72  *
73  * 3.4. Intel retains all right, title, and interest in and to the Original
74  * Intel Code.
75  *
76  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
77  * Intel shall be used in advertising or otherwise to promote the sale, use or
78  * other dealings in products derived from or relating to the Covered Code
79  * without prior written authorization from Intel.
80  *
81  * 4. Disclaimer and Export Compliance
82  *
83  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
84  * HERE.  ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
85  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT,  ASSISTANCE,
86  * INSTALLATION, TRAINING OR OTHER SERVICES.  INTEL WILL NOT PROVIDE ANY
87  * UPDATES, ENHANCEMENTS OR EXTENSIONS.  INTEL SPECIFICALLY DISCLAIMS ANY
88  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
89  * PARTICULAR PURPOSE.
90  *
91  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
92  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
93  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
94  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
95  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
96  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.  THESE LIMITATIONS
97  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
98  * LIMITED REMEDY.
99  *
100  * 4.3. Licensee shall not export, either directly or indirectly, any of this
101  * software or system incorporating such software without first obtaining any
102  * required license or other approval from the U. S. Department of Commerce or
103  * any other agency or department of the United States Government.  In the
104  * event Licensee exports any such software from the United States or
105  * re-exports any such software from a foreign destination, Licensee shall
106  * ensure that the distribution and export/re-export of the software is in
107  * compliance with all laws, regulations, orders, or other restrictions of the
108  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
109  * any of its subsidiaries will export/re-export any technical data, process,
110  * software, or service, directly or indirectly, to any country for which the
111  * United States government or any agency thereof requires an export license,
112  * other governmental approval, or letter of assurance, without first obtaining
113  * such license, approval or letter.
114  *
115  *****************************************************************************/
116 
117 
118 #define __DSWSTATE_C__
119 
120 #include "acpi.h"
121 #include "acparser.h"
122 #include "acdispat.h"
123 #include "acnamesp.h"
124 
125 #define _COMPONENT          ACPI_DISPATCHER
126         ACPI_MODULE_NAME    ("dswstate")
127 
128 /* Local prototypes */
129 
130 static ACPI_STATUS
131 AcpiDsResultStackPush (
132     ACPI_WALK_STATE         *WalkState);
133 
134 static ACPI_STATUS
135 AcpiDsResultStackPop (
136     ACPI_WALK_STATE         *WalkState);
137 
138 
139 /*******************************************************************************
140  *
141  * FUNCTION:    AcpiDsResultPop
142  *
143  * PARAMETERS:  Object              - Where to return the popped object
144  *              WalkState           - Current Walk state
145  *
146  * RETURN:      Status
147  *
148  * DESCRIPTION: Pop an object off the top of this walk's result stack
149  *
150  ******************************************************************************/
151 
152 ACPI_STATUS
153 AcpiDsResultPop (
154     ACPI_OPERAND_OBJECT     **Object,
155     ACPI_WALK_STATE         *WalkState)
156 {
157     UINT32                  Index;
158     ACPI_GENERIC_STATE      *State;
159     ACPI_STATUS             Status;
160 
161 
162     ACPI_FUNCTION_NAME (DsResultPop);
163 
164 
165     State = WalkState->Results;
166 
167     /* Incorrect state of result stack */
168 
169     if (State && !WalkState->ResultCount)
170     {
171         ACPI_ERROR ((AE_INFO, "No results on result stack"));
172         return (AE_AML_INTERNAL);
173     }
174 
175     if (!State && WalkState->ResultCount)
176     {
177         ACPI_ERROR ((AE_INFO, "No result state for result stack"));
178         return (AE_AML_INTERNAL);
179     }
180 
181     /* Empty result stack */
182 
183     if (!State)
184     {
185         ACPI_ERROR ((AE_INFO, "Result stack is empty! State=%p", WalkState));
186         return (AE_AML_NO_RETURN_VALUE);
187     }
188 
189     /* Return object of the top element and clean that top element result stack */
190 
191     WalkState->ResultCount--;
192     Index = WalkState->ResultCount % ACPI_RESULTS_FRAME_OBJ_NUM;
193 
194     *Object = State->Results.ObjDesc [Index];
195     if (!*Object)
196     {
197         ACPI_ERROR ((AE_INFO, "No result objects on result stack, State=%p",
198             WalkState));
199         return (AE_AML_NO_RETURN_VALUE);
200     }
201 
202     State->Results.ObjDesc [Index] = NULL;
203     if (Index == 0)
204     {
205         Status = AcpiDsResultStackPop (WalkState);
206         if (ACPI_FAILURE (Status))
207         {
208             return (Status);
209         }
210     }
211 
212     ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
213         "Obj=%p [%s] Index=%X State=%p Num=%X\n", *Object,
214         AcpiUtGetObjectTypeName (*Object),
215         Index, WalkState, WalkState->ResultCount));
216 
217     return (AE_OK);
218 }
219 
220 
221 /*******************************************************************************
222  *
223  * FUNCTION:    AcpiDsResultPush
224  *
225  * PARAMETERS:  Object              - Where to return the popped object
226  *              WalkState           - Current Walk state
227  *
228  * RETURN:      Status
229  *
230  * DESCRIPTION: Push an object onto the current result stack
231  *
232  ******************************************************************************/
233 
234 ACPI_STATUS
235 AcpiDsResultPush (
236     ACPI_OPERAND_OBJECT     *Object,
237     ACPI_WALK_STATE         *WalkState)
238 {
239     ACPI_GENERIC_STATE      *State;
240     ACPI_STATUS             Status;
241     UINT32                  Index;
242 
243 
244     ACPI_FUNCTION_NAME (DsResultPush);
245 
246 
247     if (WalkState->ResultCount > WalkState->ResultSize)
248     {
249         ACPI_ERROR ((AE_INFO, "Result stack is full"));
250         return (AE_AML_INTERNAL);
251     }
252     else if (WalkState->ResultCount == WalkState->ResultSize)
253     {
254         /* Extend the result stack */
255 
256         Status = AcpiDsResultStackPush (WalkState);
257         if (ACPI_FAILURE (Status))
258         {
259             ACPI_ERROR ((AE_INFO, "Failed to extend the result stack"));
260             return (Status);
261         }
262     }
263 
264     if (!(WalkState->ResultCount < WalkState->ResultSize))
265     {
266         ACPI_ERROR ((AE_INFO, "No free elements in result stack"));
267         return (AE_AML_INTERNAL);
268     }
269 
270     State = WalkState->Results;
271     if (!State)
272     {
273         ACPI_ERROR ((AE_INFO, "No result stack frame during push"));
274         return (AE_AML_INTERNAL);
275     }
276 
277     if (!Object)
278     {
279         ACPI_ERROR ((AE_INFO,
280             "Null Object! Obj=%p State=%p Num=%X",
281             Object, WalkState, WalkState->ResultCount));
282         return (AE_BAD_PARAMETER);
283     }
284 
285     /* Assign the address of object to the top free element of result stack */
286 
287     Index = WalkState->ResultCount % ACPI_RESULTS_FRAME_OBJ_NUM;
288     State->Results.ObjDesc [Index] = Object;
289     WalkState->ResultCount++;
290 
291     ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
292         Object, AcpiUtGetObjectTypeName ((ACPI_OPERAND_OBJECT *) Object),
293         WalkState, WalkState->ResultCount, WalkState->CurrentResult));
294 
295     return (AE_OK);
296 }
297 
298 
299 /*******************************************************************************
300  *
301  * FUNCTION:    AcpiDsResultStackPush
302  *
303  * PARAMETERS:  WalkState           - Current Walk state
304  *
305  * RETURN:      Status
306  *
307  * DESCRIPTION: Push an object onto the WalkState result stack
308  *
309  ******************************************************************************/
310 
311 static ACPI_STATUS
312 AcpiDsResultStackPush (
313     ACPI_WALK_STATE         *WalkState)
314 {
315     ACPI_GENERIC_STATE      *State;
316 
317 
318     ACPI_FUNCTION_NAME (DsResultStackPush);
319 
320 
321     /* Check for stack overflow */
322 
323     if (((UINT32) WalkState->ResultSize + ACPI_RESULTS_FRAME_OBJ_NUM) >
324         ACPI_RESULTS_OBJ_NUM_MAX)
325     {
326         ACPI_ERROR ((AE_INFO, "Result stack overflow: State=%p Num=%X",
327             WalkState, WalkState->ResultSize));
328         return (AE_STACK_OVERFLOW);
329     }
330 
331     State = AcpiUtCreateGenericState ();
332     if (!State)
333     {
334         return (AE_NO_MEMORY);
335     }
336 
337     State->Common.DescriptorType = ACPI_DESC_TYPE_STATE_RESULT;
338     AcpiUtPushGenericState (&WalkState->Results, State);
339 
340     /* Increase the length of the result stack by the length of frame */
341 
342     WalkState->ResultSize += ACPI_RESULTS_FRAME_OBJ_NUM;
343 
344     ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Results=%p State=%p\n",
345         State, WalkState));
346 
347     return (AE_OK);
348 }
349 
350 
351 /*******************************************************************************
352  *
353  * FUNCTION:    AcpiDsResultStackPop
354  *
355  * PARAMETERS:  WalkState           - Current Walk state
356  *
357  * RETURN:      Status
358  *
359  * DESCRIPTION: Pop an object off of the WalkState result stack
360  *
361  ******************************************************************************/
362 
363 static ACPI_STATUS
364 AcpiDsResultStackPop (
365     ACPI_WALK_STATE         *WalkState)
366 {
367     ACPI_GENERIC_STATE      *State;
368 
369 
370     ACPI_FUNCTION_NAME (DsResultStackPop);
371 
372 
373     /* Check for stack underflow */
374 
375     if (WalkState->Results == NULL)
376     {
377         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Result stack underflow - State=%p\n",
378             WalkState));
379         return (AE_AML_NO_OPERAND);
380     }
381 
382     if (WalkState->ResultSize < ACPI_RESULTS_FRAME_OBJ_NUM)
383     {
384         ACPI_ERROR ((AE_INFO, "Insufficient result stack size"));
385         return (AE_AML_INTERNAL);
386     }
387 
388     State = AcpiUtPopGenericState (&WalkState->Results);
389     AcpiUtDeleteGenericState (State);
390 
391     /* Decrease the length of result stack by the length of frame */
392 
393     WalkState->ResultSize -= ACPI_RESULTS_FRAME_OBJ_NUM;
394 
395     ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
396         "Result=%p RemainingResults=%X State=%p\n",
397         State, WalkState->ResultCount, WalkState));
398 
399     return (AE_OK);
400 }
401 
402 
403 /*******************************************************************************
404  *
405  * FUNCTION:    AcpiDsObjStackPush
406  *
407  * PARAMETERS:  Object              - Object to push
408  *              WalkState           - Current Walk state
409  *
410  * RETURN:      Status
411  *
412  * DESCRIPTION: Push an object onto this walk's object/operand stack
413  *
414  ******************************************************************************/
415 
416 ACPI_STATUS
417 AcpiDsObjStackPush (
418     void                    *Object,
419     ACPI_WALK_STATE         *WalkState)
420 {
421     ACPI_FUNCTION_NAME (DsObjStackPush);
422 
423 
424     /* Check for stack overflow */
425 
426     if (WalkState->NumOperands >= ACPI_OBJ_NUM_OPERANDS)
427     {
428         ACPI_ERROR ((AE_INFO,
429             "Object stack overflow! Obj=%p State=%p #Ops=%X",
430             Object, WalkState, WalkState->NumOperands));
431         return (AE_STACK_OVERFLOW);
432     }
433 
434     /* Put the object onto the stack */
435 
436     WalkState->Operands [WalkState->OperandIndex] = Object;
437     WalkState->NumOperands++;
438 
439     /* For the usual order of filling the operand stack */
440 
441     WalkState->OperandIndex++;
442 
443     ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
444         Object, AcpiUtGetObjectTypeName ((ACPI_OPERAND_OBJECT *) Object),
445         WalkState, WalkState->NumOperands));
446 
447     return (AE_OK);
448 }
449 
450 
451 /*******************************************************************************
452  *
453  * FUNCTION:    AcpiDsObjStackPop
454  *
455  * PARAMETERS:  PopCount            - Number of objects/entries to pop
456  *              WalkState           - Current Walk state
457  *
458  * RETURN:      Status
459  *
460  * DESCRIPTION: Pop this walk's object stack.  Objects on the stack are NOT
461  *              deleted by this routine.
462  *
463  ******************************************************************************/
464 
465 ACPI_STATUS
466 AcpiDsObjStackPop (
467     UINT32                  PopCount,
468     ACPI_WALK_STATE         *WalkState)
469 {
470     UINT32                  i;
471 
472 
473     ACPI_FUNCTION_NAME (DsObjStackPop);
474 
475 
476     for (i = 0; i < PopCount; i++)
477     {
478         /* Check for stack underflow */
479 
480         if (WalkState->NumOperands == 0)
481         {
482             ACPI_ERROR ((AE_INFO,
483                 "Object stack underflow! Count=%X State=%p #Ops=%X",
484                 PopCount, WalkState, WalkState->NumOperands));
485             return (AE_STACK_UNDERFLOW);
486         }
487 
488         /* Just set the stack entry to null */
489 
490         WalkState->NumOperands--;
491         WalkState->Operands [WalkState->NumOperands] = NULL;
492     }
493 
494     ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
495         PopCount, WalkState, WalkState->NumOperands));
496 
497     return (AE_OK);
498 }
499 
500 
501 /*******************************************************************************
502  *
503  * FUNCTION:    AcpiDsObjStackPopAndDelete
504  *
505  * PARAMETERS:  PopCount            - Number of objects/entries to pop
506  *              WalkState           - Current Walk state
507  *
508  * RETURN:      Status
509  *
510  * DESCRIPTION: Pop this walk's object stack and delete each object that is
511  *              popped off.
512  *
513  ******************************************************************************/
514 
515 void
516 AcpiDsObjStackPopAndDelete (
517     UINT32                  PopCount,
518     ACPI_WALK_STATE         *WalkState)
519 {
520     INT32                   i;
521     ACPI_OPERAND_OBJECT     *ObjDesc;
522 
523 
524     ACPI_FUNCTION_NAME (DsObjStackPopAndDelete);
525 
526 
527     if (PopCount == 0)
528     {
529         return;
530     }
531 
532     for (i = (INT32) PopCount - 1; i >= 0; i--)
533     {
534         if (WalkState->NumOperands == 0)
535         {
536             return;
537         }
538 
539         /* Pop the stack and delete an object if present in this stack entry */
540 
541         WalkState->NumOperands--;
542         ObjDesc = WalkState->Operands [i];
543         if (ObjDesc)
544         {
545             AcpiUtRemoveReference (WalkState->Operands [i]);
546             WalkState->Operands [i] = NULL;
547         }
548     }
549 
550     ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
551         PopCount, WalkState, WalkState->NumOperands));
552 }
553 
554 
555 /*******************************************************************************
556  *
557  * FUNCTION:    AcpiDsGetCurrentWalkState
558  *
559  * PARAMETERS:  Thread          - Get current active state for this Thread
560  *
561  * RETURN:      Pointer to the current walk state
562  *
563  * DESCRIPTION: Get the walk state that is at the head of the list (the "current"
564  *              walk state.)
565  *
566  ******************************************************************************/
567 
568 ACPI_WALK_STATE *
569 AcpiDsGetCurrentWalkState (
570     ACPI_THREAD_STATE       *Thread)
571 {
572     ACPI_FUNCTION_NAME (DsGetCurrentWalkState);
573 
574 
575     if (!Thread)
576     {
577         return (NULL);
578     }
579 
580     ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "Current WalkState %p\n",
581         Thread->WalkStateList));
582 
583     return (Thread->WalkStateList);
584 }
585 
586 
587 /*******************************************************************************
588  *
589  * FUNCTION:    AcpiDsPushWalkState
590  *
591  * PARAMETERS:  WalkState       - State to push
592  *              Thread          - Thread state object
593  *
594  * RETURN:      None
595  *
596  * DESCRIPTION: Place the Thread state at the head of the state list
597  *
598  ******************************************************************************/
599 
600 void
601 AcpiDsPushWalkState (
602     ACPI_WALK_STATE         *WalkState,
603     ACPI_THREAD_STATE       *Thread)
604 {
605     ACPI_FUNCTION_TRACE (DsPushWalkState);
606 
607 
608     WalkState->Next = Thread->WalkStateList;
609     Thread->WalkStateList = WalkState;
610 
611     return_VOID;
612 }
613 
614 
615 /*******************************************************************************
616  *
617  * FUNCTION:    AcpiDsPopWalkState
618  *
619  * PARAMETERS:  Thread      - Current thread state
620  *
621  * RETURN:      A WalkState object popped from the thread's stack
622  *
623  * DESCRIPTION: Remove and return the walkstate object that is at the head of
624  *              the walk stack for the given walk list.  NULL indicates that
625  *              the list is empty.
626  *
627  ******************************************************************************/
628 
629 ACPI_WALK_STATE *
630 AcpiDsPopWalkState (
631     ACPI_THREAD_STATE       *Thread)
632 {
633     ACPI_WALK_STATE         *WalkState;
634 
635 
636     ACPI_FUNCTION_TRACE (DsPopWalkState);
637 
638 
639     WalkState = Thread->WalkStateList;
640 
641     if (WalkState)
642     {
643         /* Next walk state becomes the current walk state */
644 
645         Thread->WalkStateList = WalkState->Next;
646 
647         /*
648          * Don't clear the NEXT field, this serves as an indicator
649          * that there is a parent WALK STATE
650          * Do Not: WalkState->Next = NULL;
651          */
652     }
653 
654     return_PTR (WalkState);
655 }
656 
657 
658 /*******************************************************************************
659  *
660  * FUNCTION:    AcpiDsCreateWalkState
661  *
662  * PARAMETERS:  OwnerId         - ID for object creation
663  *              Origin          - Starting point for this walk
664  *              MethodDesc      - Method object
665  *              Thread          - Current thread state
666  *
667  * RETURN:      Pointer to the new walk state.
668  *
669  * DESCRIPTION: Allocate and initialize a new walk state.  The current walk
670  *              state is set to this new state.
671  *
672  ******************************************************************************/
673 
674 ACPI_WALK_STATE *
675 AcpiDsCreateWalkState (
676     ACPI_OWNER_ID           OwnerId,
677     ACPI_PARSE_OBJECT       *Origin,
678     ACPI_OPERAND_OBJECT     *MethodDesc,
679     ACPI_THREAD_STATE       *Thread)
680 {
681     ACPI_WALK_STATE         *WalkState;
682 
683 
684     ACPI_FUNCTION_TRACE (DsCreateWalkState);
685 
686 
687     WalkState = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_WALK_STATE));
688     if (!WalkState)
689     {
690         return_PTR (NULL);
691     }
692 
693     WalkState->DescriptorType = ACPI_DESC_TYPE_WALK;
694     WalkState->MethodDesc = MethodDesc;
695     WalkState->OwnerId = OwnerId;
696     WalkState->Origin = Origin;
697     WalkState->Thread = Thread;
698 
699     WalkState->ParserState.StartOp = Origin;
700 
701     /* Init the method args/local */
702 
703 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
704     AcpiDsMethodDataInit (WalkState);
705 #endif
706 
707     /* Put the new state at the head of the walk list */
708 
709     if (Thread)
710     {
711         AcpiDsPushWalkState (WalkState, Thread);
712     }
713 
714     return_PTR (WalkState);
715 }
716 
717 
718 /*******************************************************************************
719  *
720  * FUNCTION:    AcpiDsInitAmlWalk
721  *
722  * PARAMETERS:  WalkState       - New state to be initialized
723  *              Op              - Current parse op
724  *              MethodNode      - Control method NS node, if any
725  *              AmlStart        - Start of AML
726  *              AmlLength       - Length of AML
727  *              Info            - Method info block (params, etc.)
728  *              PassNumber      - 1, 2, or 3
729  *
730  * RETURN:      Status
731  *
732  * DESCRIPTION: Initialize a walk state for a pass 1 or 2 parse tree walk
733  *
734  ******************************************************************************/
735 
736 ACPI_STATUS
737 AcpiDsInitAmlWalk (
738     ACPI_WALK_STATE         *WalkState,
739     ACPI_PARSE_OBJECT       *Op,
740     ACPI_NAMESPACE_NODE     *MethodNode,
741     UINT8                   *AmlStart,
742     UINT32                  AmlLength,
743     ACPI_EVALUATE_INFO      *Info,
744     UINT8                   PassNumber)
745 {
746     ACPI_STATUS             Status;
747     ACPI_PARSE_STATE        *ParserState = &WalkState->ParserState;
748     ACPI_PARSE_OBJECT       *ExtraOp;
749 
750 
751     ACPI_FUNCTION_TRACE (DsInitAmlWalk);
752 
753 
754     WalkState->ParserState.Aml =
755     WalkState->ParserState.AmlStart = AmlStart;
756     WalkState->ParserState.AmlEnd =
757     WalkState->ParserState.PkgEnd = AmlStart + AmlLength;
758 
759     /* The NextOp of the NextWalk will be the beginning of the method */
760 
761     WalkState->NextOp = NULL;
762     WalkState->PassNumber = PassNumber;
763 
764     if (Info)
765     {
766         WalkState->Params = Info->Parameters;
767         WalkState->CallerReturnDesc = &Info->ReturnObject;
768     }
769 
770     Status = AcpiPsInitScope (&WalkState->ParserState, Op);
771     if (ACPI_FAILURE (Status))
772     {
773         return_ACPI_STATUS (Status);
774     }
775 
776     if (MethodNode)
777     {
778         WalkState->ParserState.StartNode = MethodNode;
779         WalkState->WalkType = ACPI_WALK_METHOD;
780         WalkState->MethodNode = MethodNode;
781         WalkState->MethodDesc = AcpiNsGetAttachedObject (MethodNode);
782 
783         /* Push start scope on scope stack and make it current  */
784 
785         Status = AcpiDsScopeStackPush (MethodNode, ACPI_TYPE_METHOD, WalkState);
786         if (ACPI_FAILURE (Status))
787         {
788             return_ACPI_STATUS (Status);
789         }
790 
791         /* Init the method arguments */
792 
793         Status = AcpiDsMethodDataInitArgs (WalkState->Params,
794                     ACPI_METHOD_NUM_ARGS, WalkState);
795         if (ACPI_FAILURE (Status))
796         {
797             return_ACPI_STATUS (Status);
798         }
799     }
800     else
801     {
802         /*
803          * Setup the current scope.
804          * Find a Named Op that has a namespace node associated with it.
805          * search upwards from this Op.  Current scope is the first
806          * Op with a namespace node.
807          */
808         ExtraOp = ParserState->StartOp;
809         while (ExtraOp && !ExtraOp->Common.Node)
810         {
811             ExtraOp = ExtraOp->Common.Parent;
812         }
813 
814         if (!ExtraOp)
815         {
816             ParserState->StartNode = NULL;
817         }
818         else
819         {
820             ParserState->StartNode = ExtraOp->Common.Node;
821         }
822 
823         if (ParserState->StartNode)
824         {
825             /* Push start scope on scope stack and make it current  */
826 
827             Status = AcpiDsScopeStackPush (ParserState->StartNode,
828                             ParserState->StartNode->Type, WalkState);
829             if (ACPI_FAILURE (Status))
830             {
831                 return_ACPI_STATUS (Status);
832             }
833         }
834     }
835 
836     Status = AcpiDsInitCallbacks (WalkState, PassNumber);
837     return_ACPI_STATUS (Status);
838 }
839 
840 
841 /*******************************************************************************
842  *
843  * FUNCTION:    AcpiDsDeleteWalkState
844  *
845  * PARAMETERS:  WalkState       - State to delete
846  *
847  * RETURN:      Status
848  *
849  * DESCRIPTION: Delete a walk state including all internal data structures
850  *
851  ******************************************************************************/
852 
853 void
854 AcpiDsDeleteWalkState (
855     ACPI_WALK_STATE         *WalkState)
856 {
857     ACPI_GENERIC_STATE      *State;
858 
859 
860     ACPI_FUNCTION_TRACE_PTR (DsDeleteWalkState, WalkState);
861 
862 
863     if (!WalkState)
864     {
865         return;
866     }
867 
868     if (WalkState->DescriptorType != ACPI_DESC_TYPE_WALK)
869     {
870         ACPI_ERROR ((AE_INFO, "%p is not a valid walk state",
871             WalkState));
872         return;
873     }
874 
875     /* There should not be any open scopes */
876 
877     if (WalkState->ParserState.Scope)
878     {
879         ACPI_ERROR ((AE_INFO, "%p walk still has a scope list",
880             WalkState));
881         AcpiPsCleanupScope (&WalkState->ParserState);
882     }
883 
884     /* Always must free any linked control states */
885 
886     while (WalkState->ControlState)
887     {
888         State = WalkState->ControlState;
889         WalkState->ControlState = State->Common.Next;
890 
891         AcpiUtDeleteGenericState (State);
892     }
893 
894     /* Always must free any linked parse states */
895 
896     while (WalkState->ScopeInfo)
897     {
898         State = WalkState->ScopeInfo;
899         WalkState->ScopeInfo = State->Common.Next;
900 
901         AcpiUtDeleteGenericState (State);
902     }
903 
904     /* Always must free any stacked result states */
905 
906     while (WalkState->Results)
907     {
908         State = WalkState->Results;
909         WalkState->Results = State->Common.Next;
910 
911         AcpiUtDeleteGenericState (State);
912     }
913 
914     ACPI_FREE (WalkState);
915     return_VOID;
916 }
917 
918 
919