1 /******************************************************************************
2  *
3  * Module Name: dspkginit - Completion of deferred package initialization
4  *
5  *****************************************************************************/
6 
7 /******************************************************************************
8  *
9  * 1. Copyright Notice
10  *
11  * Some or all of this work - Copyright (c) 1999 - 2018, 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  * Alternatively, you may choose to be licensed under the terms of the
117  * following license:
118  *
119  * Redistribution and use in source and binary forms, with or without
120  * modification, are permitted provided that the following conditions
121  * are met:
122  * 1. Redistributions of source code must retain the above copyright
123  *    notice, this list of conditions, and the following disclaimer,
124  *    without modification.
125  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
126  *    substantially similar to the "NO WARRANTY" disclaimer below
127  *    ("Disclaimer") and any redistribution must be conditioned upon
128  *    including a substantially similar Disclaimer requirement for further
129  *    binary redistribution.
130  * 3. Neither the names of the above-listed copyright holders nor the names
131  *    of any contributors may be used to endorse or promote products derived
132  *    from this software without specific prior written permission.
133  *
134  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
135  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
136  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
137  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
138  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
139  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
140  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
141  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
142  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
143  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
144  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
145  *
146  * Alternatively, you may choose to be licensed under the terms of the
147  * GNU General Public License ("GPL") version 2 as published by the Free
148  * Software Foundation.
149  *
150  *****************************************************************************/
151 
152 #include "acpi.h"
153 #include "accommon.h"
154 #include "acnamesp.h"
155 #include "amlcode.h"
156 #include "acdispat.h"
157 #include "acinterp.h"
158 #include "acparser.h"
159 
160 
161 #define _COMPONENT          ACPI_NAMESPACE
162         ACPI_MODULE_NAME    ("dspkginit")
163 
164 
165 /* Local prototypes */
166 
167 static void
168 AcpiDsResolvePackageElement (
169     ACPI_OPERAND_OBJECT     **Element);
170 
171 
172 /*******************************************************************************
173  *
174  * FUNCTION:    AcpiDsBuildInternalPackageObj
175  *
176  * PARAMETERS:  WalkState       - Current walk state
177  *              Op              - Parser object to be translated
178  *              ElementCount    - Number of elements in the package - this is
179  *                                the NumElements argument to Package()
180  *              ObjDescPtr      - Where the ACPI internal object is returned
181  *
182  * RETURN:      Status
183  *
184  * DESCRIPTION: Translate a parser Op package object to the equivalent
185  *              namespace object
186  *
187  * NOTE: The number of elements in the package will be always be the NumElements
188  * count, regardless of the number of elements in the package list. If
189  * NumElements is smaller, only that many package list elements are used.
190  * if NumElements is larger, the Package object is padded out with
191  * objects of type Uninitialized (as per ACPI spec.)
192  *
193  * Even though the ASL compilers do not allow NumElements to be smaller
194  * than the Package list length (for the fixed length package opcode), some
195  * BIOS code modifies the AML on the fly to adjust the NumElements, and
196  * this code compensates for that. This also provides compatibility with
197  * other AML interpreters.
198  *
199  ******************************************************************************/
200 
201 ACPI_STATUS
AcpiDsBuildInternalPackageObj(ACPI_WALK_STATE * WalkState,ACPI_PARSE_OBJECT * Op,UINT32 ElementCount,ACPI_OPERAND_OBJECT ** ObjDescPtr)202 AcpiDsBuildInternalPackageObj (
203     ACPI_WALK_STATE         *WalkState,
204     ACPI_PARSE_OBJECT       *Op,
205     UINT32                  ElementCount,
206     ACPI_OPERAND_OBJECT     **ObjDescPtr)
207 {
208     ACPI_PARSE_OBJECT       *Arg;
209     ACPI_PARSE_OBJECT       *Parent;
210     ACPI_OPERAND_OBJECT     *ObjDesc = NULL;
211     ACPI_STATUS             Status = AE_OK;
212     BOOLEAN                 ModuleLevelCode = FALSE;
213     UINT16                  ReferenceCount;
214     UINT32                  Index;
215     UINT32                  i;
216 
217 
218     ACPI_FUNCTION_TRACE (DsBuildInternalPackageObj);
219 
220 
221     /* Check if we are executing module level code */
222 
223     if (WalkState->ParseFlags & ACPI_PARSE_MODULE_LEVEL)
224     {
225         ModuleLevelCode = TRUE;
226     }
227 
228     /* Find the parent of a possibly nested package */
229 
230     Parent = Op->Common.Parent;
231     while ((Parent->Common.AmlOpcode == AML_PACKAGE_OP) ||
232            (Parent->Common.AmlOpcode == AML_VARIABLE_PACKAGE_OP))
233     {
234         Parent = Parent->Common.Parent;
235     }
236 
237     /*
238      * If we are evaluating a Named package object of the form:
239      *      Name (xxxx, Package)
240      * the package object already exists, otherwise it must be created.
241      */
242     ObjDesc = *ObjDescPtr;
243     if (!ObjDesc)
244     {
245         ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_PACKAGE);
246         *ObjDescPtr = ObjDesc;
247         if (!ObjDesc)
248         {
249             return_ACPI_STATUS (AE_NO_MEMORY);
250         }
251 
252         ObjDesc->Package.Node = Parent->Common.Node;
253     }
254 
255     if (ObjDesc->Package.Flags & AOPOBJ_DATA_VALID) /* Just in case */
256     {
257         return_ACPI_STATUS (AE_OK);
258     }
259 
260     /*
261      * Allocate the element array (array of pointers to the individual
262      * objects) if necessary. the count is based on the NumElements
263      * parameter. Add an extra pointer slot so that the list is always
264      * null terminated.
265      */
266     if (!ObjDesc->Package.Elements)
267     {
268         ObjDesc->Package.Elements = ACPI_ALLOCATE_ZEROED (
269             ((ACPI_SIZE) ElementCount + 1) * sizeof (void *));
270 
271         if (!ObjDesc->Package.Elements)
272         {
273             AcpiUtDeleteObjectDesc (ObjDesc);
274             return_ACPI_STATUS (AE_NO_MEMORY);
275         }
276 
277         ObjDesc->Package.Count = ElementCount;
278     }
279 
280     /* First arg is element count. Second arg begins the initializer list */
281 
282     Arg = Op->Common.Value.Arg;
283     Arg = Arg->Common.Next;
284 
285     /*
286      * If we are executing module-level code, we will defer the
287      * full resolution of the package elements in order to support
288      * forward references from the elements. This provides
289      * compatibility with other ACPI implementations.
290      */
291     if (ModuleLevelCode)
292     {
293         ObjDesc->Package.AmlStart = WalkState->Aml;
294         ObjDesc->Package.AmlLength = 0;
295 
296         ACPI_DEBUG_PRINT_RAW ((ACPI_DB_PARSE,
297             "%s: Deferring resolution of Package elements\n",
298             ACPI_GET_FUNCTION_NAME));
299     }
300 
301     /*
302      * Initialize the elements of the package, up to the NumElements count.
303      * Package is automatically padded with uninitialized (NULL) elements
304      * if NumElements is greater than the package list length. Likewise,
305      * Package is truncated if NumElements is less than the list length.
306      */
307     for (i = 0; Arg && (i < ElementCount); i++)
308     {
309         if (Arg->Common.AmlOpcode == AML_INT_RETURN_VALUE_OP)
310         {
311             if (Arg->Common.Node->Type == ACPI_TYPE_METHOD)
312             {
313                 /*
314                  * A method reference "looks" to the parser to be a method
315                  * invocation, so we special case it here
316                  */
317                 Arg->Common.AmlOpcode = AML_INT_NAMEPATH_OP;
318                 Status = AcpiDsBuildInternalObject (
319                     WalkState, Arg, &ObjDesc->Package.Elements[i]);
320             }
321             else
322             {
323                 /* This package element is already built, just get it */
324 
325                 ObjDesc->Package.Elements[i] =
326                     ACPI_CAST_PTR (ACPI_OPERAND_OBJECT, Arg->Common.Node);
327             }
328         }
329         else
330         {
331             Status = AcpiDsBuildInternalObject (
332                 WalkState, Arg, &ObjDesc->Package.Elements[i]);
333             if (Status == AE_NOT_FOUND)
334             {
335                 ACPI_ERROR ((AE_INFO, "%-48s", "****DS namepath not found"));
336             }
337 
338             if (!ModuleLevelCode)
339             {
340                 /*
341                  * Initialize this package element. This function handles the
342                  * resolution of named references within the package.
343                  * Forward references from module-level code are deferred
344                  * until all ACPI tables are loaded.
345                  */
346                 AcpiDsInitPackageElement (0, ObjDesc->Package.Elements[i],
347                     NULL, &ObjDesc->Package.Elements[i]);
348             }
349         }
350 
351         if (*ObjDescPtr)
352         {
353             /* Existing package, get existing reference count */
354 
355             ReferenceCount = (*ObjDescPtr)->Common.ReferenceCount;
356             if (ReferenceCount > 1)
357             {
358                 /* Make new element ref count match original ref count */
359                 /* TBD: Probably need an AcpiUtAddReferences function */
360 
361                 for (Index = 0; Index < ((UINT32) ReferenceCount - 1); Index++)
362                 {
363                     AcpiUtAddReference ((ObjDesc->Package.Elements[i]));
364                 }
365             }
366         }
367 
368         Arg = Arg->Common.Next;
369     }
370 
371     /* Check for match between NumElements and actual length of PackageList */
372 
373     if (Arg)
374     {
375         /*
376          * NumElements was exhausted, but there are remaining elements in
377          * the PackageList. Truncate the package to NumElements.
378          *
379          * Note: technically, this is an error, from ACPI spec: "It is an
380          * error for NumElements to be less than the number of elements in
381          * the PackageList". However, we just print a message and no
382          * exception is returned. This provides compatibility with other
383          * ACPI implementations. Some firmware implementations will alter
384          * the NumElements on the fly, possibly creating this type of
385          * ill-formed package object.
386          */
387         while (Arg)
388         {
389             /*
390              * We must delete any package elements that were created earlier
391              * and are not going to be used because of the package truncation.
392              */
393             if (Arg->Common.Node)
394             {
395                 AcpiUtRemoveReference (
396                     ACPI_CAST_PTR (ACPI_OPERAND_OBJECT, Arg->Common.Node));
397                 Arg->Common.Node = NULL;
398             }
399 
400             /* Find out how many elements there really are */
401 
402             i++;
403             Arg = Arg->Common.Next;
404         }
405 
406         ACPI_INFO ((
407             "Actual Package length (%u) is larger than "
408             "NumElements field (%u), truncated",
409             i, ElementCount));
410     }
411     else if (i < ElementCount)
412     {
413         /*
414          * Arg list (elements) was exhausted, but we did not reach
415          * NumElements count.
416          *
417          * Note: this is not an error, the package is padded out
418          * with NULLs as per the ACPI specification.
419          */
420         ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INFO,
421             "%s: Package List length (%u) smaller than NumElements "
422             "count (%u), padded with null elements\n",
423             ACPI_GET_FUNCTION_NAME, i, ElementCount));
424     }
425 
426     /* Module-level packages will be resolved later */
427 
428     if (!ModuleLevelCode)
429     {
430         ObjDesc->Package.Flags |= AOPOBJ_DATA_VALID;
431     }
432 
433     Op->Common.Node = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, ObjDesc);
434     return_ACPI_STATUS (Status);
435 }
436 
437 
438 /*******************************************************************************
439  *
440  * FUNCTION:    AcpiDsInitPackageElement
441  *
442  * PARAMETERS:  ACPI_PKG_CALLBACK
443  *
444  * RETURN:      Status
445  *
446  * DESCRIPTION: Resolve a named reference element within a package object
447  *
448  ******************************************************************************/
449 
450 ACPI_STATUS
AcpiDsInitPackageElement(UINT8 ObjectType,ACPI_OPERAND_OBJECT * SourceObject,ACPI_GENERIC_STATE * State,void * Context)451 AcpiDsInitPackageElement (
452     UINT8                   ObjectType,
453     ACPI_OPERAND_OBJECT     *SourceObject,
454     ACPI_GENERIC_STATE      *State,
455     void                    *Context)
456 {
457     ACPI_OPERAND_OBJECT     **ElementPtr;
458 
459 
460     ACPI_FUNCTION_TRACE (DsInitPackageElement);
461 
462 
463     if (!SourceObject)
464     {
465         return_ACPI_STATUS (AE_OK);
466     }
467 
468     /*
469      * The following code is a bit of a hack to workaround a (current)
470      * limitation of the ACPI_PKG_CALLBACK interface. We need a pointer
471      * to the location within the element array because a new object
472      * may be created and stored there.
473      */
474     if (Context)
475     {
476         /* A direct call was made to this function */
477 
478         ElementPtr = (ACPI_OPERAND_OBJECT **) Context;
479     }
480     else
481     {
482         /* Call came from AcpiUtWalkPackageTree */
483 
484         ElementPtr = State->Pkg.ThisTargetObj;
485     }
486 
487     /* We are only interested in reference objects/elements */
488 
489     if (SourceObject->Common.Type == ACPI_TYPE_LOCAL_REFERENCE)
490     {
491         /* Attempt to resolve the (named) reference to a namespace node */
492 
493         AcpiDsResolvePackageElement (ElementPtr);
494     }
495     else if (SourceObject->Common.Type == ACPI_TYPE_PACKAGE)
496     {
497         SourceObject->Package.Flags |= AOPOBJ_DATA_VALID;
498     }
499 
500     return_ACPI_STATUS (AE_OK);
501 }
502 
503 
504 /*******************************************************************************
505  *
506  * FUNCTION:    AcpiDsResolvePackageElement
507  *
508  * PARAMETERS:  ElementPtr          - Pointer to a reference object
509  *
510  * RETURN:      Possible new element is stored to the indirect ElementPtr
511  *
512  * DESCRIPTION: Resolve a package element that is a reference to a named
513  *              object.
514  *
515  ******************************************************************************/
516 
517 static void
AcpiDsResolvePackageElement(ACPI_OPERAND_OBJECT ** ElementPtr)518 AcpiDsResolvePackageElement (
519     ACPI_OPERAND_OBJECT     **ElementPtr)
520 {
521     ACPI_STATUS             Status;
522     ACPI_STATUS             Status2;
523     ACPI_GENERIC_STATE      ScopeInfo;
524     ACPI_OPERAND_OBJECT     *Element = *ElementPtr;
525     ACPI_NAMESPACE_NODE     *ResolvedNode;
526     ACPI_NAMESPACE_NODE     *OriginalNode;
527     char                    *ExternalPath = "";
528     ACPI_OBJECT_TYPE        Type;
529 
530 
531     ACPI_FUNCTION_TRACE (DsResolvePackageElement);
532 
533 
534     /* Check if reference element is already resolved */
535 
536     if (Element->Reference.Resolved)
537     {
538         ACPI_DEBUG_PRINT_RAW ((ACPI_DB_PARSE,
539             "%s: Package element is already resolved\n",
540             ACPI_GET_FUNCTION_NAME));
541 
542         return_VOID;
543     }
544 
545     /* Element must be a reference object of correct type */
546 
547     ScopeInfo.Scope.Node = Element->Reference.Node; /* Prefix node */
548 
549     Status = AcpiNsLookup (&ScopeInfo, (char *) Element->Reference.Aml,
550         ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
551         ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE,
552         NULL, &ResolvedNode);
553     if (ACPI_FAILURE (Status))
554     {
555         if ((Status == AE_NOT_FOUND) && AcpiGbl_IgnorePackageResolutionErrors)
556         {
557             /*
558              * Optionally be silent about the NOT_FOUND case for the referenced
559              * name. Although this is potentially a serious problem,
560              * it can generate a lot of noise/errors on platforms whose
561              * firmware carries around a bunch of unused Package objects.
562              * To disable these errors, set this global to TRUE:
563              *     AcpiGbl_IgnorePackageResolutionErrors
564              *
565              * If the AML actually tries to use such a package, the unresolved
566              * element(s) will be replaced with NULL elements.
567              */
568 
569             /* Referenced name not found, set the element to NULL */
570 
571             AcpiUtRemoveReference (*ElementPtr);
572             *ElementPtr = NULL;
573             return_VOID;
574         }
575 
576         Status2 = AcpiNsExternalizeName (ACPI_UINT32_MAX,
577             (char *) Element->Reference.Aml, NULL, &ExternalPath);
578 
579         ACPI_EXCEPTION ((AE_INFO, Status,
580             "While resolving a named reference package element - %s",
581             ExternalPath));
582         if (ACPI_SUCCESS (Status2))
583         {
584             ACPI_FREE (ExternalPath);
585         }
586 
587         /* Could not resolve name, set the element to NULL */
588 
589         AcpiUtRemoveReference (*ElementPtr);
590         *ElementPtr = NULL;
591         return_VOID;
592     }
593     else if (ResolvedNode->Type == ACPI_TYPE_ANY)
594     {
595         /* Named reference not resolved, return a NULL package element */
596 
597         ACPI_ERROR ((AE_INFO,
598             "Could not resolve named package element [%4.4s] in [%4.4s]",
599             ResolvedNode->Name.Ascii, ScopeInfo.Scope.Node->Name.Ascii));
600         *ElementPtr = NULL;
601         return_VOID;
602     }
603 
604     /*
605      * Special handling for Alias objects. We need ResolvedNode to point
606      * to the Alias target. This effectively "resolves" the alias.
607      */
608     if (ResolvedNode->Type == ACPI_TYPE_LOCAL_ALIAS)
609     {
610         ResolvedNode = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE,
611             ResolvedNode->Object);
612     }
613 
614     /* Update the reference object */
615 
616     Element->Reference.Resolved = TRUE;
617     Element->Reference.Node = ResolvedNode;
618     Type = Element->Reference.Node->Type;
619 
620     /*
621      * Attempt to resolve the node to a value before we insert it into
622      * the package. If this is a reference to a common data type,
623      * resolve it immediately. According to the ACPI spec, package
624      * elements can only be "data objects" or method references.
625      * Attempt to resolve to an Integer, Buffer, String or Package.
626      * If cannot, return the named reference (for things like Devices,
627      * Methods, etc.) Buffer Fields and Fields will resolve to simple
628      * objects (int/buf/str/pkg).
629      *
630      * NOTE: References to things like Devices, Methods, Mutexes, etc.
631      * will remain as named references. This behavior is not described
632      * in the ACPI spec, but it appears to be an oversight.
633      */
634     OriginalNode = ResolvedNode;
635     Status = AcpiExResolveNodeToValue (&ResolvedNode, NULL);
636     if (ACPI_FAILURE (Status))
637     {
638         return_VOID;
639     }
640 
641     switch (Type)
642     {
643     /*
644      * These object types are a result of named references, so we will
645      * leave them as reference objects. In other words, these types
646      * have no intrinsic "value".
647      */
648     case ACPI_TYPE_DEVICE:
649     case ACPI_TYPE_THERMAL:
650     case ACPI_TYPE_METHOD:
651         break;
652 
653     case ACPI_TYPE_MUTEX:
654     case ACPI_TYPE_POWER:
655     case ACPI_TYPE_PROCESSOR:
656     case ACPI_TYPE_EVENT:
657     case ACPI_TYPE_REGION:
658 
659         /* AcpiExResolveNodeToValue gave these an extra reference */
660 
661         AcpiUtRemoveReference (OriginalNode->Object);
662         break;
663 
664     default:
665         /*
666          * For all other types - the node was resolved to an actual
667          * operand object with a value, return the object. Remove
668          * a reference on the existing object.
669          */
670         AcpiUtRemoveReference (Element);
671         *ElementPtr = (ACPI_OPERAND_OBJECT *) ResolvedNode;
672         break;
673     }
674 
675     return_VOID;
676 }
677