dsmthdat.c revision 99679
1/*******************************************************************************
2 *
3 * Module Name: dsmthdat - control method arguments and local variables
4 *              $Revision: 62 $
5 *
6 ******************************************************************************/
7
8/******************************************************************************
9 *
10 * 1. Copyright Notice
11 *
12 * Some or all of this work - Copyright (c) 1999 - 2002, 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#define __DSMTHDAT_C__
118
119#include "acpi.h"
120#include "acdispat.h"
121#include "amlcode.h"
122#include "acnamesp.h"
123
124
125#define _COMPONENT          ACPI_DISPATCHER
126        ACPI_MODULE_NAME    ("dsmthdat")
127
128
129/*******************************************************************************
130 *
131 * FUNCTION:    AcpiDsMethodDataInit
132 *
133 * PARAMETERS:  WalkState           - Current walk state object
134 *
135 * RETURN:      Status
136 *
137 * DESCRIPTION: Initialize the data structures that hold the method's arguments
138 *              and locals.  The data struct is an array of NTEs for each.
139 *              This allows RefOf and DeRefOf to work properly for these
140 *              special data types.
141 *
142 * NOTES:       WalkState fields are initialized to zero by the
143 *              ACPI_MEM_CALLOCATE().
144 *
145 *              A pseudo-Namespace Node is assigned to each argument and local
146 *              so that RefOf() can return a pointer to the Node.
147 *
148 ******************************************************************************/
149
150void
151AcpiDsMethodDataInit (
152    ACPI_WALK_STATE         *WalkState)
153{
154    UINT32                  i;
155
156
157    ACPI_FUNCTION_TRACE ("DsMethodDataInit");
158
159
160    /* Init the method arguments */
161
162    for (i = 0; i < MTH_NUM_ARGS; i++)
163    {
164        ACPI_MOVE_UNALIGNED32_TO_32 (&WalkState->Arguments[i].Name,
165                                NAMEOF_ARG_NTE);
166        WalkState->Arguments[i].Name.Integer |= (i << 24);
167        WalkState->Arguments[i].Descriptor    = ACPI_DESC_TYPE_NAMED;
168        WalkState->Arguments[i].Type          = ACPI_TYPE_ANY;
169        WalkState->Arguments[i].Flags         = ANOBJ_END_OF_PEER_LIST | ANOBJ_METHOD_ARG;
170    }
171
172    /* Init the method locals */
173
174    for (i = 0; i < MTH_NUM_LOCALS; i++)
175    {
176        ACPI_MOVE_UNALIGNED32_TO_32 (&WalkState->LocalVariables[i].Name,
177                                NAMEOF_LOCAL_NTE);
178
179        WalkState->LocalVariables[i].Name.Integer |= (i << 24);
180        WalkState->LocalVariables[i].Descriptor    = ACPI_DESC_TYPE_NAMED;
181        WalkState->LocalVariables[i].Type          = ACPI_TYPE_ANY;
182        WalkState->LocalVariables[i].Flags         = ANOBJ_END_OF_PEER_LIST | ANOBJ_METHOD_LOCAL;
183    }
184
185    return_VOID;
186}
187
188
189/*******************************************************************************
190 *
191 * FUNCTION:    AcpiDsMethodDataDeleteAll
192 *
193 * PARAMETERS:  WalkState           - Current walk state object
194 *
195 * RETURN:      None
196 *
197 * DESCRIPTION: Delete method locals and arguments.  Arguments are only
198 *              deleted if this method was called from another method.
199 *
200 ******************************************************************************/
201
202void
203AcpiDsMethodDataDeleteAll (
204    ACPI_WALK_STATE         *WalkState)
205{
206    UINT32                  Index;
207
208
209    ACPI_FUNCTION_TRACE ("DsMethodDataDeleteAll");
210
211
212    /* Detach the locals */
213
214    for (Index = 0; Index < MTH_NUM_LOCALS; Index++)
215    {
216        if (WalkState->LocalVariables[Index].Object)
217        {
218            ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Deleting Local%d=%p\n",
219                    Index, WalkState->LocalVariables[Index].Object));
220
221            /* Detach object (if present) and remove a reference */
222
223            AcpiNsDetachObject (&WalkState->LocalVariables[Index]);
224        }
225    }
226
227    /* Detach the arguments */
228
229    for (Index = 0; Index < MTH_NUM_ARGS; Index++)
230    {
231        if (WalkState->Arguments[Index].Object)
232        {
233            ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Deleting Arg%d=%p\n",
234                    Index, WalkState->Arguments[Index].Object));
235
236            /* Detach object (if present) and remove a reference */
237
238            AcpiNsDetachObject (&WalkState->Arguments[Index]);
239        }
240    }
241
242    return_VOID;
243}
244
245
246/*******************************************************************************
247 *
248 * FUNCTION:    AcpiDsMethodDataInitArgs
249 *
250 * PARAMETERS:  *Params         - Pointer to a parameter list for the method
251 *              MaxParamCount   - The arg count for this method
252 *              WalkState       - Current walk state object
253 *
254 * RETURN:      Status
255 *
256 * DESCRIPTION: Initialize arguments for a method.  The parameter list is a list
257 *              of ACPI operand objects, either null terminated or whose length
258 *              is defined by MaxParamCount.
259 *
260 ******************************************************************************/
261
262ACPI_STATUS
263AcpiDsMethodDataInitArgs (
264    ACPI_OPERAND_OBJECT     **Params,
265    UINT32                  MaxParamCount,
266    ACPI_WALK_STATE         *WalkState)
267{
268    ACPI_STATUS             Status;
269    UINT32                  Index = 0;
270
271
272    ACPI_FUNCTION_TRACE_PTR ("DsMethodDataInitArgs", Params);
273
274
275    if (!Params)
276    {
277        ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "No param list passed to method\n"));
278        return_ACPI_STATUS (AE_OK);
279    }
280
281    /* Copy passed parameters into the new method stack frame  */
282
283    while ((Index < MTH_NUM_ARGS) && (Index < MaxParamCount) && Params[Index])
284    {
285        /*
286         * A valid parameter.
287         * Store the argument in the method/walk descriptor
288         */
289        Status = AcpiDsStoreObjectToLocal (AML_ARG_OP, Index, Params[Index],
290                                            WalkState);
291        if (ACPI_FAILURE (Status))
292        {
293            return_ACPI_STATUS (Status);
294        }
295
296        Index++;
297    }
298
299    ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "%d args passed to method\n", Index));
300    return_ACPI_STATUS (AE_OK);
301}
302
303
304/*******************************************************************************
305 *
306 * FUNCTION:    AcpiDsMethodDataGetNode
307 *
308 * PARAMETERS:  Opcode              - Either AML_LOCAL_OP or AML_ARG_OP
309 *              Index               - Which localVar or argument whose type
310 *                                      to get
311 *              WalkState           - Current walk state object
312 *
313 * RETURN:      Get the Node associated with a local or arg.
314 *
315 ******************************************************************************/
316
317ACPI_STATUS
318AcpiDsMethodDataGetNode (
319    UINT16                  Opcode,
320    UINT32                  Index,
321    ACPI_WALK_STATE         *WalkState,
322    ACPI_NAMESPACE_NODE     **Node)
323{
324    ACPI_FUNCTION_TRACE ("DsMethodDataGetNode");
325
326
327    /*
328     * Method Locals and Arguments are supported
329     */
330    switch (Opcode)
331    {
332    case AML_LOCAL_OP:
333
334        if (Index > MTH_MAX_LOCAL)
335        {
336            ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Local index %d is invalid (max %d)\n",
337                Index, MTH_MAX_LOCAL));
338            return_ACPI_STATUS (AE_AML_INVALID_INDEX);
339        }
340
341        /* Return a pointer to the pseudo-node */
342
343        *Node = &WalkState->LocalVariables[Index];
344        break;
345
346    case AML_ARG_OP:
347
348        if (Index > MTH_MAX_ARG)
349        {
350            ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Arg index %d is invalid (max %d)\n",
351                Index, MTH_MAX_ARG));
352            return_ACPI_STATUS (AE_AML_INVALID_INDEX);
353        }
354
355        /* Return a pointer to the pseudo-node */
356
357        *Node = &WalkState->Arguments[Index];
358        break;
359
360    default:
361        ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Opcode %d is invalid\n", Opcode));
362        return_ACPI_STATUS (AE_AML_BAD_OPCODE);
363    }
364
365    return_ACPI_STATUS (AE_OK);
366}
367
368
369/*******************************************************************************
370 *
371 * FUNCTION:    AcpiDsMethodDataSetValue
372 *
373 * PARAMETERS:  Opcode              - Either AML_LOCAL_OP or AML_ARG_OP
374 *              Index               - Which localVar or argument to get
375 *              Object              - Object to be inserted into the stack entry
376 *              WalkState           - Current walk state object
377 *
378 * RETURN:      Status
379 *
380 * DESCRIPTION: Insert an object onto the method stack at entry Opcode:Index.
381 *
382 ******************************************************************************/
383
384ACPI_STATUS
385AcpiDsMethodDataSetValue (
386    UINT16                  Opcode,
387    UINT32                  Index,
388    ACPI_OPERAND_OBJECT     *Object,
389    ACPI_WALK_STATE         *WalkState)
390{
391    ACPI_STATUS             Status;
392    ACPI_NAMESPACE_NODE     *Node;
393
394
395    ACPI_FUNCTION_TRACE ("DsMethodDataSetValue");
396
397
398    /* Get the namespace node for the arg/local */
399
400    Status = AcpiDsMethodDataGetNode (Opcode, Index, WalkState, &Node);
401    if (ACPI_FAILURE (Status))
402    {
403        return_ACPI_STATUS (Status);
404    }
405
406    /* Increment ref count so object can't be deleted while installed */
407
408    AcpiUtAddReference (Object);
409
410    /* Install the object into the stack entry */
411
412    Node->Object = Object;
413    return_ACPI_STATUS (AE_OK);
414}
415
416
417/*******************************************************************************
418 *
419 * FUNCTION:    AcpiDsMethodDataGetType
420 *
421 * PARAMETERS:  Opcode              - Either AML_LOCAL_OP or AML_ARG_OP
422 *              Index               - Which localVar or argument whose type
423 *                                      to get
424 *              WalkState           - Current walk state object
425 *
426 * RETURN:      Data type of current value of the selected Arg or Local
427 *
428 ******************************************************************************/
429
430ACPI_OBJECT_TYPE
431AcpiDsMethodDataGetType (
432    UINT16                  Opcode,
433    UINT32                  Index,
434    ACPI_WALK_STATE         *WalkState)
435{
436    ACPI_STATUS             Status;
437    ACPI_NAMESPACE_NODE     *Node;
438    ACPI_OPERAND_OBJECT     *Object;
439
440
441    ACPI_FUNCTION_TRACE ("DsMethodDataGetType");
442
443
444    /* Get the namespace node for the arg/local */
445
446    Status = AcpiDsMethodDataGetNode (Opcode, Index, WalkState, &Node);
447    if (ACPI_FAILURE (Status))
448    {
449        return_VALUE ((ACPI_TYPE_NOT_FOUND));
450    }
451
452    /* Get the object */
453
454    Object = AcpiNsGetAttachedObject (Node);
455    if (!Object)
456    {
457        /* Uninitialized local/arg, return TYPE_ANY */
458
459        return_VALUE (ACPI_TYPE_ANY);
460    }
461
462    /* Get the object type */
463
464    return_VALUE (ACPI_GET_OBJECT_TYPE (Object));
465}
466
467
468/*******************************************************************************
469 *
470 * FUNCTION:    AcpiDsMethodDataGetValue
471 *
472 * PARAMETERS:  Opcode              - Either AML_LOCAL_OP or AML_ARG_OP
473 *              Index               - Which localVar or argument to get
474 *              WalkState           - Current walk state object
475 *              *DestDesc           - Ptr to Descriptor into which selected Arg
476 *                                    or Local value should be copied
477 *
478 * RETURN:      Status
479 *
480 * DESCRIPTION: Retrieve value of selected Arg or Local from the method frame
481 *              at the current top of the method stack.
482 *              Used only in AcpiExResolveToValue().
483 *
484 ******************************************************************************/
485
486ACPI_STATUS
487AcpiDsMethodDataGetValue (
488    UINT16                  Opcode,
489    UINT32                  Index,
490    ACPI_WALK_STATE         *WalkState,
491    ACPI_OPERAND_OBJECT     **DestDesc)
492{
493    ACPI_STATUS             Status;
494    ACPI_NAMESPACE_NODE     *Node;
495    ACPI_OPERAND_OBJECT     *Object;
496
497
498    ACPI_FUNCTION_TRACE ("DsMethodDataGetValue");
499
500
501    /* Validate the object descriptor */
502
503    if (!DestDesc)
504    {
505        ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Null object descriptor pointer\n"));
506        return_ACPI_STATUS (AE_BAD_PARAMETER);
507    }
508
509    /* Get the namespace node for the arg/local */
510
511    Status = AcpiDsMethodDataGetNode (Opcode, Index, WalkState, &Node);
512    if (ACPI_FAILURE (Status))
513    {
514        return_ACPI_STATUS (Status);
515    }
516
517    /* Get the object from the node */
518
519    Object = Node->Object;
520
521    /* Examine the returned object, it must be valid. */
522
523    if (!Object)
524    {
525        /*
526         * Index points to uninitialized object.
527         * This means that either 1) The expected argument was
528         * not passed to the method, or 2) A local variable
529         * was referenced by the method (via the ASL)
530         * before it was initialized.  Either case is an error.
531         */
532        switch (Opcode)
533        {
534        case AML_ARG_OP:
535
536            ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Uninitialized Arg[%d] at node %p\n",
537                Index, Node));
538
539            return_ACPI_STATUS (AE_AML_UNINITIALIZED_ARG);
540
541        case AML_LOCAL_OP:
542
543            ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Uninitialized Local[%d] at node %p\n",
544                Index, Node));
545
546            return_ACPI_STATUS (AE_AML_UNINITIALIZED_LOCAL);
547
548        default:
549            return_ACPI_STATUS (AE_AML_INTERNAL);
550        }
551    }
552
553    /*
554     * The Index points to an initialized and valid object.
555     * Return an additional reference to the object
556     */
557    *DestDesc = Object;
558    AcpiUtAddReference (Object);
559
560    return_ACPI_STATUS (AE_OK);
561}
562
563
564/*******************************************************************************
565 *
566 * FUNCTION:    AcpiDsMethodDataDeleteValue
567 *
568 * PARAMETERS:  Opcode              - Either AML_LOCAL_OP or AML_ARG_OP
569 *              Index               - Which localVar or argument to delete
570 *              WalkState           - Current walk state object
571 *
572 * RETURN:      None
573 *
574 * DESCRIPTION: Delete the entry at Opcode:Index on the method stack.  Inserts
575 *              a null into the stack slot after the object is deleted.
576 *
577 ******************************************************************************/
578
579void
580AcpiDsMethodDataDeleteValue (
581    UINT16                  Opcode,
582    UINT32                  Index,
583    ACPI_WALK_STATE         *WalkState)
584{
585    ACPI_STATUS             Status;
586    ACPI_NAMESPACE_NODE     *Node;
587    ACPI_OPERAND_OBJECT     *Object;
588
589
590    ACPI_FUNCTION_TRACE ("DsMethodDataDeleteValue");
591
592
593    /* Get the namespace node for the arg/local */
594
595    Status = AcpiDsMethodDataGetNode (Opcode, Index, WalkState, &Node);
596    if (ACPI_FAILURE (Status))
597    {
598        return_VOID;
599    }
600
601    /* Get the associated object */
602
603    Object = AcpiNsGetAttachedObject (Node);
604
605    /*
606     * Undefine the Arg or Local by setting its descriptor
607     * pointer to NULL. Locals/Args can contain both
608     * ACPI_OPERAND_OBJECTS and ACPI_NAMESPACE_NODEs
609     */
610    Node->Object = NULL;
611
612    if ((Object) &&
613        (ACPI_GET_DESCRIPTOR_TYPE (Object) == ACPI_DESC_TYPE_OPERAND))
614    {
615        /*
616         * There is a valid object.
617         * Decrement the reference count by one to balance the
618         * increment when the object was stored.
619         */
620        AcpiUtRemoveReference (Object);
621    }
622
623    return_VOID;
624}
625
626
627/*******************************************************************************
628 *
629 * FUNCTION:    AcpiDsStoreObjectToLocal
630 *
631 * PARAMETERS:  Opcode              - Either AML_LOCAL_OP or AML_ARG_OP
632 *              Index               - Which localVar or argument to set
633 *              ObjDesc             - Value to be stored
634 *              WalkState           - Current walk state
635 *
636 * RETURN:      Status
637 *
638 * DESCRIPTION: Store a value in an Arg or Local.  The ObjDesc is installed
639 *              as the new value for the Arg or Local and the reference count
640 *              for ObjDesc is incremented.
641 *
642 ******************************************************************************/
643
644ACPI_STATUS
645AcpiDsStoreObjectToLocal (
646    UINT16                  Opcode,
647    UINT32                  Index,
648    ACPI_OPERAND_OBJECT     *ObjDesc,
649    ACPI_WALK_STATE         *WalkState)
650{
651    ACPI_STATUS             Status;
652    ACPI_NAMESPACE_NODE     *Node;
653    ACPI_OPERAND_OBJECT     *CurrentObjDesc;
654
655
656    ACPI_FUNCTION_TRACE ("DsStoreObjectToLocal");
657    ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Opcode=%d Idx=%d Obj=%p\n",
658        Opcode, Index, ObjDesc));
659
660
661    /* Parameter validation */
662
663    if (!ObjDesc)
664    {
665        return_ACPI_STATUS (AE_BAD_PARAMETER);
666    }
667
668    /* Get the namespace node for the arg/local */
669
670    Status = AcpiDsMethodDataGetNode (Opcode, Index, WalkState, &Node);
671    if (ACPI_FAILURE (Status))
672    {
673        return_ACPI_STATUS (Status);
674    }
675
676    CurrentObjDesc = AcpiNsGetAttachedObject (Node);
677    if (CurrentObjDesc == ObjDesc)
678    {
679        ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Obj=%p already installed!\n", ObjDesc));
680        return_ACPI_STATUS (Status);
681    }
682
683    /*
684     * If there is an object already in this slot, we either
685     * have to delete it, or if this is an argument and there
686     * is an object reference stored there, we have to do
687     * an indirect store!
688     */
689    if (CurrentObjDesc)
690    {
691        /*
692         * Check for an indirect store if an argument
693         * contains an object reference (stored as an Node).
694         * We don't allow this automatic dereferencing for
695         * locals, since a store to a local should overwrite
696         * anything there, including an object reference.
697         *
698         * If both Arg0 and Local0 contain RefOf (Local4):
699         *
700         * Store (1, Arg0)             - Causes indirect store to local4
701         * Store (1, Local0)           - Stores 1 in local0, overwriting
702         *                                  the reference to local4
703         * Store (1, DeRefof (Local0)) - Causes indirect store to local4
704         *
705         * Weird, but true.
706         */
707        if ((Opcode == AML_ARG_OP) &&
708            (ACPI_GET_DESCRIPTOR_TYPE (CurrentObjDesc) == ACPI_DESC_TYPE_NAMED))
709        {
710            ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
711                "Arg (%p) is an ObjRef(Node), storing in node %p\n",
712                ObjDesc, CurrentObjDesc));
713
714            /* Detach an existing object from the Node */
715
716            AcpiNsDetachObject ((ACPI_NAMESPACE_NODE *) CurrentObjDesc);
717
718            /*
719             * Store this object into the Node
720             * (perform the indirect store)
721             */
722            Status = AcpiNsAttachObject ((ACPI_NAMESPACE_NODE *) CurrentObjDesc,
723                            ObjDesc, ACPI_GET_OBJECT_TYPE (ObjDesc));
724            return_ACPI_STATUS (Status);
725        }
726
727        /*
728         * Delete the existing object
729         * before storing the new one
730         */
731        AcpiDsMethodDataDeleteValue (Opcode, Index, WalkState);
732    }
733
734    /*
735     * Install the ObjStack descriptor (*ObjDesc) into
736     * the descriptor for the Arg or Local.
737     * Install the new object in the stack entry
738     * (increments the object reference count by one)
739     */
740    Status = AcpiDsMethodDataSetValue (Opcode, Index, ObjDesc, WalkState);
741    return_ACPI_STATUS (Status);
742}
743
744
745