afbcc6217e98c2c4fdfa83b8cb8e5acbbf9a3951
[reactos.git] / reactos / drivers / bus / acpi / acpica / parser / psparse.c
1 /******************************************************************************
2 *
3 * Module Name: psparse - Parser top level AML parse routines
4 *
5 *****************************************************************************/
6
7 /******************************************************************************
8 *
9 * 1. Copyright Notice
10 *
11 * Some or all of this work - Copyright (c) 1999 - 2014, 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 * Parse the AML and build an operation tree as most interpreters,
118 * like Perl, do. Parsing is done by hand rather than with a YACC
119 * generated parser to tightly constrain stack and dynamic memory
120 * usage. At the same time, parsing is kept flexible and the code
121 * fairly compact by parsing based on a list of AML opcode
122 * templates in AmlOpInfo[]
123 */
124
125 #include "acpi.h"
126 #include "accommon.h"
127 #include "acparser.h"
128 #include "acdispat.h"
129 #include "amlcode.h"
130 #include "acinterp.h"
131
132 #define _COMPONENT ACPI_PARSER
133 ACPI_MODULE_NAME ("psparse")
134
135
136 /*******************************************************************************
137 *
138 * FUNCTION: AcpiPsGetOpcodeSize
139 *
140 * PARAMETERS: Opcode - An AML opcode
141 *
142 * RETURN: Size of the opcode, in bytes (1 or 2)
143 *
144 * DESCRIPTION: Get the size of the current opcode.
145 *
146 ******************************************************************************/
147
148 UINT32
149 AcpiPsGetOpcodeSize (
150 UINT32 Opcode)
151 {
152
153 /* Extended (2-byte) opcode if > 255 */
154
155 if (Opcode > 0x00FF)
156 {
157 return (2);
158 }
159
160 /* Otherwise, just a single byte opcode */
161
162 return (1);
163 }
164
165
166 /*******************************************************************************
167 *
168 * FUNCTION: AcpiPsPeekOpcode
169 *
170 * PARAMETERS: ParserState - A parser state object
171 *
172 * RETURN: Next AML opcode
173 *
174 * DESCRIPTION: Get next AML opcode (without incrementing AML pointer)
175 *
176 ******************************************************************************/
177
178 UINT16
179 AcpiPsPeekOpcode (
180 ACPI_PARSE_STATE *ParserState)
181 {
182 UINT8 *Aml;
183 UINT16 Opcode;
184
185
186 Aml = ParserState->Aml;
187 Opcode = (UINT16) ACPI_GET8 (Aml);
188
189 if (Opcode == AML_EXTENDED_OP_PREFIX)
190 {
191 /* Extended opcode, get the second opcode byte */
192
193 Aml++;
194 Opcode = (UINT16) ((Opcode << 8) | ACPI_GET8 (Aml));
195 }
196
197 return (Opcode);
198 }
199
200
201 /*******************************************************************************
202 *
203 * FUNCTION: AcpiPsCompleteThisOp
204 *
205 * PARAMETERS: WalkState - Current State
206 * Op - Op to complete
207 *
208 * RETURN: Status
209 *
210 * DESCRIPTION: Perform any cleanup at the completion of an Op.
211 *
212 ******************************************************************************/
213
214 ACPI_STATUS
215 AcpiPsCompleteThisOp (
216 ACPI_WALK_STATE *WalkState,
217 ACPI_PARSE_OBJECT *Op)
218 {
219 ACPI_PARSE_OBJECT *Prev;
220 ACPI_PARSE_OBJECT *Next;
221 const ACPI_OPCODE_INFO *ParentInfo;
222 ACPI_PARSE_OBJECT *ReplacementOp = NULL;
223 ACPI_STATUS Status = AE_OK;
224
225
226 ACPI_FUNCTION_TRACE_PTR (PsCompleteThisOp, Op);
227
228
229 /* Check for null Op, can happen if AML code is corrupt */
230
231 if (!Op)
232 {
233 return_ACPI_STATUS (AE_OK); /* OK for now */
234 }
235
236 /* Delete this op and the subtree below it if asked to */
237
238 if (((WalkState->ParseFlags & ACPI_PARSE_TREE_MASK) != ACPI_PARSE_DELETE_TREE) ||
239 (WalkState->OpInfo->Class == AML_CLASS_ARGUMENT))
240 {
241 return_ACPI_STATUS (AE_OK);
242 }
243
244 /* Make sure that we only delete this subtree */
245
246 if (Op->Common.Parent)
247 {
248 Prev = Op->Common.Parent->Common.Value.Arg;
249 if (!Prev)
250 {
251 /* Nothing more to do */
252
253 goto Cleanup;
254 }
255
256 /*
257 * Check if we need to replace the operator and its subtree
258 * with a return value op (placeholder op)
259 */
260 ParentInfo = AcpiPsGetOpcodeInfo (Op->Common.Parent->Common.AmlOpcode);
261
262 switch (ParentInfo->Class)
263 {
264 case AML_CLASS_CONTROL:
265
266 break;
267
268 case AML_CLASS_CREATE:
269 /*
270 * These opcodes contain TermArg operands. The current
271 * op must be replaced by a placeholder return op
272 */
273 ReplacementOp = AcpiPsAllocOp (AML_INT_RETURN_VALUE_OP);
274 if (!ReplacementOp)
275 {
276 Status = AE_NO_MEMORY;
277 }
278 break;
279
280 case AML_CLASS_NAMED_OBJECT:
281 /*
282 * These opcodes contain TermArg operands. The current
283 * op must be replaced by a placeholder return op
284 */
285 if ((Op->Common.Parent->Common.AmlOpcode == AML_REGION_OP) ||
286 (Op->Common.Parent->Common.AmlOpcode == AML_DATA_REGION_OP) ||
287 (Op->Common.Parent->Common.AmlOpcode == AML_BUFFER_OP) ||
288 (Op->Common.Parent->Common.AmlOpcode == AML_PACKAGE_OP) ||
289 (Op->Common.Parent->Common.AmlOpcode == AML_BANK_FIELD_OP) ||
290 (Op->Common.Parent->Common.AmlOpcode == AML_VAR_PACKAGE_OP))
291 {
292 ReplacementOp = AcpiPsAllocOp (AML_INT_RETURN_VALUE_OP);
293 if (!ReplacementOp)
294 {
295 Status = AE_NO_MEMORY;
296 }
297 }
298 else if ((Op->Common.Parent->Common.AmlOpcode == AML_NAME_OP) &&
299 (WalkState->PassNumber <= ACPI_IMODE_LOAD_PASS2))
300 {
301 if ((Op->Common.AmlOpcode == AML_BUFFER_OP) ||
302 (Op->Common.AmlOpcode == AML_PACKAGE_OP) ||
303 (Op->Common.AmlOpcode == AML_VAR_PACKAGE_OP))
304 {
305 ReplacementOp = AcpiPsAllocOp (Op->Common.AmlOpcode);
306 if (!ReplacementOp)
307 {
308 Status = AE_NO_MEMORY;
309 }
310 else
311 {
312 ReplacementOp->Named.Data = Op->Named.Data;
313 ReplacementOp->Named.Length = Op->Named.Length;
314 }
315 }
316 }
317 break;
318
319 default:
320
321 ReplacementOp = AcpiPsAllocOp (AML_INT_RETURN_VALUE_OP);
322 if (!ReplacementOp)
323 {
324 Status = AE_NO_MEMORY;
325 }
326 }
327
328 /* We must unlink this op from the parent tree */
329
330 if (Prev == Op)
331 {
332 /* This op is the first in the list */
333
334 if (ReplacementOp)
335 {
336 ReplacementOp->Common.Parent = Op->Common.Parent;
337 ReplacementOp->Common.Value.Arg = NULL;
338 ReplacementOp->Common.Node = Op->Common.Node;
339 Op->Common.Parent->Common.Value.Arg = ReplacementOp;
340 ReplacementOp->Common.Next = Op->Common.Next;
341 }
342 else
343 {
344 Op->Common.Parent->Common.Value.Arg = Op->Common.Next;
345 }
346 }
347
348 /* Search the parent list */
349
350 else while (Prev)
351 {
352 /* Traverse all siblings in the parent's argument list */
353
354 Next = Prev->Common.Next;
355 if (Next == Op)
356 {
357 if (ReplacementOp)
358 {
359 ReplacementOp->Common.Parent = Op->Common.Parent;
360 ReplacementOp->Common.Value.Arg = NULL;
361 ReplacementOp->Common.Node = Op->Common.Node;
362 Prev->Common.Next = ReplacementOp;
363 ReplacementOp->Common.Next = Op->Common.Next;
364 Next = NULL;
365 }
366 else
367 {
368 Prev->Common.Next = Op->Common.Next;
369 Next = NULL;
370 }
371 }
372 Prev = Next;
373 }
374 }
375
376
377 Cleanup:
378
379 /* Now we can actually delete the subtree rooted at Op */
380
381 AcpiPsDeleteParseTree (Op);
382 return_ACPI_STATUS (Status);
383 }
384
385
386 /*******************************************************************************
387 *
388 * FUNCTION: AcpiPsNextParseState
389 *
390 * PARAMETERS: WalkState - Current state
391 * Op - Current parse op
392 * CallbackStatus - Status from previous operation
393 *
394 * RETURN: Status
395 *
396 * DESCRIPTION: Update the parser state based upon the return exception from
397 * the parser callback.
398 *
399 ******************************************************************************/
400
401 ACPI_STATUS
402 AcpiPsNextParseState (
403 ACPI_WALK_STATE *WalkState,
404 ACPI_PARSE_OBJECT *Op,
405 ACPI_STATUS CallbackStatus)
406 {
407 ACPI_PARSE_STATE *ParserState = &WalkState->ParserState;
408 ACPI_STATUS Status = AE_CTRL_PENDING;
409
410
411 ACPI_FUNCTION_TRACE_PTR (PsNextParseState, Op);
412
413
414 switch (CallbackStatus)
415 {
416 case AE_CTRL_TERMINATE:
417 /*
418 * A control method was terminated via a RETURN statement.
419 * The walk of this method is complete.
420 */
421 ParserState->Aml = ParserState->AmlEnd;
422 Status = AE_CTRL_TERMINATE;
423 break;
424
425 case AE_CTRL_BREAK:
426
427 ParserState->Aml = WalkState->AmlLastWhile;
428 WalkState->ControlState->Common.Value = FALSE;
429 Status = AE_CTRL_BREAK;
430 break;
431
432 case AE_CTRL_CONTINUE:
433
434 ParserState->Aml = WalkState->AmlLastWhile;
435 Status = AE_CTRL_CONTINUE;
436 break;
437
438 case AE_CTRL_PENDING:
439
440 ParserState->Aml = WalkState->AmlLastWhile;
441 break;
442
443 #if 0
444 case AE_CTRL_SKIP:
445
446 ParserState->Aml = ParserState->Scope->ParseScope.PkgEnd;
447 Status = AE_OK;
448 break;
449 #endif
450
451 case AE_CTRL_TRUE:
452 /*
453 * Predicate of an IF was true, and we are at the matching ELSE.
454 * Just close out this package
455 */
456 ParserState->Aml = AcpiPsGetNextPackageEnd (ParserState);
457 Status = AE_CTRL_PENDING;
458 break;
459
460 case AE_CTRL_FALSE:
461 /*
462 * Either an IF/WHILE Predicate was false or we encountered a BREAK
463 * opcode. In both cases, we do not execute the rest of the
464 * package; We simply close out the parent (finishing the walk of
465 * this branch of the tree) and continue execution at the parent
466 * level.
467 */
468 ParserState->Aml = ParserState->Scope->ParseScope.PkgEnd;
469
470 /* In the case of a BREAK, just force a predicate (if any) to FALSE */
471
472 WalkState->ControlState->Common.Value = FALSE;
473 Status = AE_CTRL_END;
474 break;
475
476 case AE_CTRL_TRANSFER:
477
478 /* A method call (invocation) -- transfer control */
479
480 Status = AE_CTRL_TRANSFER;
481 WalkState->PrevOp = Op;
482 WalkState->MethodCallOp = Op;
483 WalkState->MethodCallNode = (Op->Common.Value.Arg)->Common.Node;
484
485 /* Will return value (if any) be used by the caller? */
486
487 WalkState->ReturnUsed = AcpiDsIsResultUsed (Op, WalkState);
488 break;
489
490 default:
491
492 Status = CallbackStatus;
493 if ((CallbackStatus & AE_CODE_MASK) == AE_CODE_CONTROL)
494 {
495 Status = AE_OK;
496 }
497 break;
498 }
499
500 return_ACPI_STATUS (Status);
501 }
502
503
504 /*******************************************************************************
505 *
506 * FUNCTION: AcpiPsParseAml
507 *
508 * PARAMETERS: WalkState - Current state
509 *
510 *
511 * RETURN: Status
512 *
513 * DESCRIPTION: Parse raw AML and return a tree of ops
514 *
515 ******************************************************************************/
516
517 ACPI_STATUS
518 AcpiPsParseAml (
519 ACPI_WALK_STATE *WalkState)
520 {
521 ACPI_STATUS Status;
522 ACPI_THREAD_STATE *Thread;
523 ACPI_THREAD_STATE *PrevWalkList = AcpiGbl_CurrentWalkList;
524 ACPI_WALK_STATE *PreviousWalkState;
525
526
527 ACPI_FUNCTION_TRACE (PsParseAml);
528
529 ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
530 "Entered with WalkState=%p Aml=%p size=%X\n",
531 WalkState, WalkState->ParserState.Aml,
532 WalkState->ParserState.AmlSize));
533
534 if (!WalkState->ParserState.Aml)
535 {
536 return_ACPI_STATUS (AE_NULL_OBJECT);
537 }
538
539 /* Create and initialize a new thread state */
540
541 Thread = AcpiUtCreateThreadState ();
542 if (!Thread)
543 {
544 if (WalkState->MethodDesc)
545 {
546 /* Executing a control method - additional cleanup */
547
548 AcpiDsTerminateControlMethod (WalkState->MethodDesc, WalkState);
549 }
550
551 AcpiDsDeleteWalkState (WalkState);
552 return_ACPI_STATUS (AE_NO_MEMORY);
553 }
554
555 WalkState->Thread = Thread;
556
557 /*
558 * If executing a method, the starting SyncLevel is this method's
559 * SyncLevel
560 */
561 if (WalkState->MethodDesc)
562 {
563 WalkState->Thread->CurrentSyncLevel = WalkState->MethodDesc->Method.SyncLevel;
564 }
565
566 AcpiDsPushWalkState (WalkState, Thread);
567
568 /*
569 * This global allows the AML debugger to get a handle to the currently
570 * executing control method.
571 */
572 AcpiGbl_CurrentWalkList = Thread;
573
574 /*
575 * Execute the walk loop as long as there is a valid Walk State. This
576 * handles nested control method invocations without recursion.
577 */
578 ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "State=%p\n", WalkState));
579
580 Status = AE_OK;
581 while (WalkState)
582 {
583 if (ACPI_SUCCESS (Status))
584 {
585 /*
586 * The ParseLoop executes AML until the method terminates
587 * or calls another method.
588 */
589 Status = AcpiPsParseLoop (WalkState);
590 }
591
592 ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
593 "Completed one call to walk loop, %s State=%p\n",
594 AcpiFormatException (Status), WalkState));
595
596 if (Status == AE_CTRL_TRANSFER)
597 {
598 /*
599 * A method call was detected.
600 * Transfer control to the called control method
601 */
602 Status = AcpiDsCallControlMethod (Thread, WalkState, NULL);
603 if (ACPI_FAILURE (Status))
604 {
605 Status = AcpiDsMethodError (Status, WalkState);
606 }
607
608 /*
609 * If the transfer to the new method method call worked, a new walk
610 * state was created -- get it
611 */
612 WalkState = AcpiDsGetCurrentWalkState (Thread);
613 continue;
614 }
615 else if (Status == AE_CTRL_TERMINATE)
616 {
617 Status = AE_OK;
618 }
619 else if ((Status != AE_OK) && (WalkState->MethodDesc))
620 {
621 /* Either the method parse or actual execution failed */
622
623 ACPI_ERROR_METHOD ("Method parse/execution failed",
624 WalkState->MethodNode, NULL, Status);
625
626 /* Check for possible multi-thread reentrancy problem */
627
628 if ((Status == AE_ALREADY_EXISTS) &&
629 (!(WalkState->MethodDesc->Method.InfoFlags & ACPI_METHOD_SERIALIZED)))
630 {
631 /*
632 * Method is not serialized and tried to create an object
633 * twice. The probable cause is that the method cannot
634 * handle reentrancy. Mark as "pending serialized" now, and
635 * then mark "serialized" when the last thread exits.
636 */
637 WalkState->MethodDesc->Method.InfoFlags |=
638 ACPI_METHOD_SERIALIZED_PENDING;
639 }
640 }
641
642 /* We are done with this walk, move on to the parent if any */
643
644 WalkState = AcpiDsPopWalkState (Thread);
645
646 /* Reset the current scope to the beginning of scope stack */
647
648 AcpiDsScopeStackClear (WalkState);
649
650 /*
651 * If we just returned from the execution of a control method or if we
652 * encountered an error during the method parse phase, there's lots of
653 * cleanup to do
654 */
655 if (((WalkState->ParseFlags & ACPI_PARSE_MODE_MASK) == ACPI_PARSE_EXECUTE) ||
656 (ACPI_FAILURE (Status)))
657 {
658 AcpiDsTerminateControlMethod (WalkState->MethodDesc, WalkState);
659 }
660
661 /* Delete this walk state and all linked control states */
662
663 AcpiPsCleanupScope (&WalkState->ParserState);
664 PreviousWalkState = WalkState;
665
666 ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
667 "ReturnValue=%p, ImplicitValue=%p State=%p\n",
668 WalkState->ReturnDesc, WalkState->ImplicitReturnObj, WalkState));
669
670 /* Check if we have restarted a preempted walk */
671
672 WalkState = AcpiDsGetCurrentWalkState (Thread);
673 if (WalkState)
674 {
675 if (ACPI_SUCCESS (Status))
676 {
677 /*
678 * There is another walk state, restart it.
679 * If the method return value is not used by the parent,
680 * The object is deleted
681 */
682 if (!PreviousWalkState->ReturnDesc)
683 {
684 /*
685 * In slack mode execution, if there is no return value
686 * we should implicitly return zero (0) as a default value.
687 */
688 if (AcpiGbl_EnableInterpreterSlack &&
689 !PreviousWalkState->ImplicitReturnObj)
690 {
691 PreviousWalkState->ImplicitReturnObj =
692 AcpiUtCreateIntegerObject ((UINT64) 0);
693 if (!PreviousWalkState->ImplicitReturnObj)
694 {
695 return_ACPI_STATUS (AE_NO_MEMORY);
696 }
697 }
698
699 /* Restart the calling control method */
700
701 Status = AcpiDsRestartControlMethod (WalkState,
702 PreviousWalkState->ImplicitReturnObj);
703 }
704 else
705 {
706 /*
707 * We have a valid return value, delete any implicit
708 * return value.
709 */
710 AcpiDsClearImplicitReturn (PreviousWalkState);
711
712 Status = AcpiDsRestartControlMethod (WalkState,
713 PreviousWalkState->ReturnDesc);
714 }
715 if (ACPI_SUCCESS (Status))
716 {
717 WalkState->WalkType |= ACPI_WALK_METHOD_RESTART;
718 }
719 }
720 else
721 {
722 /* On error, delete any return object or implicit return */
723
724 AcpiUtRemoveReference (PreviousWalkState->ReturnDesc);
725 AcpiDsClearImplicitReturn (PreviousWalkState);
726 }
727 }
728
729 /*
730 * Just completed a 1st-level method, save the final internal return
731 * value (if any)
732 */
733 else if (PreviousWalkState->CallerReturnDesc)
734 {
735 if (PreviousWalkState->ImplicitReturnObj)
736 {
737 *(PreviousWalkState->CallerReturnDesc) =
738 PreviousWalkState->ImplicitReturnObj;
739 }
740 else
741 {
742 /* NULL if no return value */
743
744 *(PreviousWalkState->CallerReturnDesc) =
745 PreviousWalkState->ReturnDesc;
746 }
747 }
748 else
749 {
750 if (PreviousWalkState->ReturnDesc)
751 {
752 /* Caller doesn't want it, must delete it */
753
754 AcpiUtRemoveReference (PreviousWalkState->ReturnDesc);
755 }
756 if (PreviousWalkState->ImplicitReturnObj)
757 {
758 /* Caller doesn't want it, must delete it */
759
760 AcpiUtRemoveReference (PreviousWalkState->ImplicitReturnObj);
761 }
762 }
763
764 AcpiDsDeleteWalkState (PreviousWalkState);
765 }
766
767 /* Normal exit */
768
769 AcpiExReleaseAllMutexes (Thread);
770 AcpiUtDeleteGenericState (ACPI_CAST_PTR (ACPI_GENERIC_STATE, Thread));
771 AcpiGbl_CurrentWalkList = PrevWalkList;
772 return_ACPI_STATUS (Status);
773 }