1 /******************************************************************************
2  *
3  * Module Name: exresolv - AML Interpreter object resolution
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2020, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #include "acpi.h"
45 #include "accommon.h"
46 #include "amlcode.h"
47 #include "acdispat.h"
48 #include "acinterp.h"
49 #include "acnamesp.h"
50 
51 
52 #define _COMPONENT          ACPI_EXECUTER
53         ACPI_MODULE_NAME    ("exresolv")
54 
55 /* Local prototypes */
56 
57 static ACPI_STATUS
58 AcpiExResolveObjectToValue (
59     ACPI_OPERAND_OBJECT     **StackPtr,
60     ACPI_WALK_STATE         *WalkState);
61 
62 
63 /*******************************************************************************
64  *
65  * FUNCTION:    AcpiExResolveToValue
66  *
67  * PARAMETERS:  **StackPtr          - Points to entry on ObjStack, which can
68  *                                    be either an (ACPI_OPERAND_OBJECT *)
69  *                                    or an ACPI_HANDLE.
70  *              WalkState           - Current method state
71  *
72  * RETURN:      Status
73  *
74  * DESCRIPTION: Convert Reference objects to values
75  *
76  ******************************************************************************/
77 
78 ACPI_STATUS
79 AcpiExResolveToValue (
80     ACPI_OPERAND_OBJECT     **StackPtr,
81     ACPI_WALK_STATE         *WalkState)
82 {
83     ACPI_STATUS             Status;
84 
85 
86     ACPI_FUNCTION_TRACE_PTR (ExResolveToValue, StackPtr);
87 
88 
89     if (!StackPtr || !*StackPtr)
90     {
91         ACPI_ERROR ((AE_INFO, "Internal - null pointer"));
92         return_ACPI_STATUS (AE_AML_NO_OPERAND);
93     }
94 
95     /*
96      * The entity pointed to by the StackPtr can be either
97      * 1) A valid ACPI_OPERAND_OBJECT, or
98      * 2) A ACPI_NAMESPACE_NODE (NamedObj)
99      */
100     if (ACPI_GET_DESCRIPTOR_TYPE (*StackPtr) == ACPI_DESC_TYPE_OPERAND)
101     {
102         Status = AcpiExResolveObjectToValue (StackPtr, WalkState);
103         if (ACPI_FAILURE (Status))
104         {
105             return_ACPI_STATUS (Status);
106         }
107 
108         if (!*StackPtr)
109         {
110             ACPI_ERROR ((AE_INFO, "Internal - null pointer"));
111             return_ACPI_STATUS (AE_AML_NO_OPERAND);
112         }
113     }
114 
115     /*
116      * Object on the stack may have changed if AcpiExResolveObjectToValue()
117      * was called (i.e., we can't use an _else_ here.)
118      */
119     if (ACPI_GET_DESCRIPTOR_TYPE (*StackPtr) == ACPI_DESC_TYPE_NAMED)
120     {
121         Status = AcpiExResolveNodeToValue (
122             ACPI_CAST_INDIRECT_PTR (ACPI_NAMESPACE_NODE, StackPtr),
123             WalkState);
124         if (ACPI_FAILURE (Status))
125         {
126             return_ACPI_STATUS (Status);
127         }
128     }
129 
130     ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Resolved object %p\n", *StackPtr));
131     return_ACPI_STATUS (AE_OK);
132 }
133 
134 
135 /*******************************************************************************
136  *
137  * FUNCTION:    AcpiExResolveObjectToValue
138  *
139  * PARAMETERS:  StackPtr        - Pointer to an internal object
140  *              WalkState       - Current method state
141  *
142  * RETURN:      Status
143  *
144  * DESCRIPTION: Retrieve the value from an internal object. The Reference type
145  *              uses the associated AML opcode to determine the value.
146  *
147  ******************************************************************************/
148 
149 static ACPI_STATUS
150 AcpiExResolveObjectToValue (
151     ACPI_OPERAND_OBJECT     **StackPtr,
152     ACPI_WALK_STATE         *WalkState)
153 {
154     ACPI_STATUS             Status = AE_OK;
155     ACPI_OPERAND_OBJECT     *StackDesc;
156     ACPI_OPERAND_OBJECT     *ObjDesc = NULL;
157     UINT8                   RefType;
158 
159 
160     ACPI_FUNCTION_TRACE (ExResolveObjectToValue);
161 
162 
163     StackDesc = *StackPtr;
164 
165     /* This is an object of type ACPI_OPERAND_OBJECT */
166 
167     switch (StackDesc->Common.Type)
168     {
169     case ACPI_TYPE_LOCAL_REFERENCE:
170 
171         RefType = StackDesc->Reference.Class;
172 
173         switch (RefType)
174         {
175         case ACPI_REFCLASS_LOCAL:
176         case ACPI_REFCLASS_ARG:
177             /*
178              * Get the local from the method's state info
179              * Note: this increments the local's object reference count
180              */
181             Status = AcpiDsMethodDataGetValue (RefType,
182                 StackDesc->Reference.Value, WalkState, &ObjDesc);
183             if (ACPI_FAILURE (Status))
184             {
185                 return_ACPI_STATUS (Status);
186             }
187 
188             ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "[Arg/Local %X] ValueObj is %p\n",
189                 StackDesc->Reference.Value, ObjDesc));
190 
191             /*
192              * Now we can delete the original Reference Object and
193              * replace it with the resolved value
194              */
195             AcpiUtRemoveReference (StackDesc);
196             *StackPtr = ObjDesc;
197             break;
198 
199         case ACPI_REFCLASS_INDEX:
200 
201             switch (StackDesc->Reference.TargetType)
202             {
203             case ACPI_TYPE_BUFFER_FIELD:
204 
205                 /* Just return - do not dereference */
206                 break;
207 
208             case ACPI_TYPE_PACKAGE:
209 
210                 /* If method call or CopyObject - do not dereference */
211 
212                 if ((WalkState->Opcode == AML_INT_METHODCALL_OP) ||
213                     (WalkState->Opcode == AML_COPY_OBJECT_OP))
214                 {
215                     break;
216                 }
217 
218                 /* Otherwise, dereference the PackageIndex to a package element */
219 
220                 ObjDesc = *StackDesc->Reference.Where;
221                 if (ObjDesc)
222                 {
223                     /*
224                      * Valid object descriptor, copy pointer to return value
225                      * (i.e., dereference the package index)
226                      * Delete the ref object, increment the returned object
227                      */
228                     AcpiUtAddReference (ObjDesc);
229                     *StackPtr = ObjDesc;
230                 }
231                 else
232                 {
233                     /*
234                      * A NULL object descriptor means an uninitialized element of
235                      * the package, can't dereference it
236                      */
237                     ACPI_ERROR ((AE_INFO,
238                         "Attempt to dereference an Index to "
239                         "NULL package element Idx=%p",
240                         StackDesc));
241                     Status = AE_AML_UNINITIALIZED_ELEMENT;
242                 }
243                 break;
244 
245             default:
246 
247                 /* Invalid reference object */
248 
249                 ACPI_ERROR ((AE_INFO,
250                     "Unknown TargetType 0x%X in Index/Reference object %p",
251                     StackDesc->Reference.TargetType, StackDesc));
252                 Status = AE_AML_INTERNAL;
253                 break;
254             }
255             break;
256 
257         case ACPI_REFCLASS_REFOF:
258         case ACPI_REFCLASS_DEBUG:
259         case ACPI_REFCLASS_TABLE:
260 
261             /* Just leave the object as-is, do not dereference */
262 
263             break;
264 
265         case ACPI_REFCLASS_NAME:   /* Reference to a named object */
266 
267             /* Dereference the name */
268 
269             if ((StackDesc->Reference.Node->Type == ACPI_TYPE_DEVICE) ||
270                 (StackDesc->Reference.Node->Type == ACPI_TYPE_THERMAL))
271             {
272                 /* These node types do not have 'real' subobjects */
273 
274                 *StackPtr = (void *) StackDesc->Reference.Node;
275             }
276             else
277             {
278                 /* Get the object pointed to by the namespace node */
279 
280                 *StackPtr = (StackDesc->Reference.Node)->Object;
281                 AcpiUtAddReference (*StackPtr);
282             }
283 
284             AcpiUtRemoveReference (StackDesc);
285             break;
286 
287         default:
288 
289             ACPI_ERROR ((AE_INFO,
290                 "Unknown Reference type 0x%X in %p",
291                 RefType, StackDesc));
292             Status = AE_AML_INTERNAL;
293             break;
294         }
295         break;
296 
297     case ACPI_TYPE_BUFFER:
298 
299         Status = AcpiDsGetBufferArguments (StackDesc);
300         break;
301 
302     case ACPI_TYPE_PACKAGE:
303 
304         Status = AcpiDsGetPackageArguments (StackDesc);
305         break;
306 
307     case ACPI_TYPE_BUFFER_FIELD:
308     case ACPI_TYPE_LOCAL_REGION_FIELD:
309     case ACPI_TYPE_LOCAL_BANK_FIELD:
310     case ACPI_TYPE_LOCAL_INDEX_FIELD:
311 
312         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
313             "FieldRead SourceDesc=%p Type=%X\n",
314             StackDesc, StackDesc->Common.Type));
315 
316         Status = AcpiExReadDataFromField (WalkState, StackDesc, &ObjDesc);
317 
318         /* Remove a reference to the original operand, then override */
319 
320         AcpiUtRemoveReference (*StackPtr);
321         *StackPtr = (void *) ObjDesc;
322         break;
323 
324     default:
325 
326         break;
327     }
328 
329     return_ACPI_STATUS (Status);
330 }
331 
332 
333 /*******************************************************************************
334  *
335  * FUNCTION:    AcpiExResolveMultiple
336  *
337  * PARAMETERS:  WalkState           - Current state (contains AML opcode)
338  *              Operand             - Starting point for resolution
339  *              ReturnType          - Where the object type is returned
340  *              ReturnDesc          - Where the resolved object is returned
341  *
342  * RETURN:      Status
343  *
344  * DESCRIPTION: Return the base object and type. Traverse a reference list if
345  *              necessary to get to the base object.
346  *
347  ******************************************************************************/
348 
349 ACPI_STATUS
350 AcpiExResolveMultiple (
351     ACPI_WALK_STATE         *WalkState,
352     ACPI_OPERAND_OBJECT     *Operand,
353     ACPI_OBJECT_TYPE        *ReturnType,
354     ACPI_OPERAND_OBJECT     **ReturnDesc)
355 {
356     ACPI_OPERAND_OBJECT     *ObjDesc = ACPI_CAST_PTR (void, Operand);
357     ACPI_NAMESPACE_NODE     *Node = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, Operand);
358     ACPI_OBJECT_TYPE        Type;
359     ACPI_STATUS             Status;
360 
361 
362     ACPI_FUNCTION_TRACE (AcpiExResolveMultiple);
363 
364 
365     /* Operand can be either a namespace node or an operand descriptor */
366 
367     switch (ACPI_GET_DESCRIPTOR_TYPE (ObjDesc))
368     {
369     case ACPI_DESC_TYPE_OPERAND:
370 
371         Type = ObjDesc->Common.Type;
372         break;
373 
374     case ACPI_DESC_TYPE_NAMED:
375 
376         Type = ((ACPI_NAMESPACE_NODE *) ObjDesc)->Type;
377         ObjDesc = AcpiNsGetAttachedObject (Node);
378 
379         /* If we had an Alias node, use the attached object for type info */
380 
381         if (Type == ACPI_TYPE_LOCAL_ALIAS)
382         {
383             Type = ((ACPI_NAMESPACE_NODE *) ObjDesc)->Type;
384             ObjDesc = AcpiNsGetAttachedObject (
385                 (ACPI_NAMESPACE_NODE *) ObjDesc);
386         }
387 
388         switch (Type)
389         {
390         case ACPI_TYPE_DEVICE:
391         case ACPI_TYPE_THERMAL:
392 
393             /* These types have no attached subobject */
394             break;
395 
396         default:
397 
398             /* All other types require a subobject */
399 
400             if (!ObjDesc)
401             {
402                 ACPI_ERROR ((AE_INFO,
403                     "[%4.4s] Node is unresolved or uninitialized",
404                     AcpiUtGetNodeName (Node)));
405                 return_ACPI_STATUS (AE_AML_UNINITIALIZED_NODE);
406             }
407             break;
408         }
409         break;
410 
411     default:
412         return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
413     }
414 
415     /* If type is anything other than a reference, we are done */
416 
417     if (Type != ACPI_TYPE_LOCAL_REFERENCE)
418     {
419         goto Exit;
420     }
421 
422     /*
423      * For reference objects created via the RefOf, Index, or Load/LoadTable
424      * operators, we need to get to the base object (as per the ACPI
425      * specification of the ObjectType and SizeOf operators). This means
426      * traversing the list of possibly many nested references.
427      */
428     while (ObjDesc->Common.Type == ACPI_TYPE_LOCAL_REFERENCE)
429     {
430         switch (ObjDesc->Reference.Class)
431         {
432         case ACPI_REFCLASS_REFOF:
433         case ACPI_REFCLASS_NAME:
434 
435             /* Dereference the reference pointer */
436 
437             if (ObjDesc->Reference.Class == ACPI_REFCLASS_REFOF)
438             {
439                 Node = ObjDesc->Reference.Object;
440             }
441             else /* AML_INT_NAMEPATH_OP */
442             {
443                 Node = ObjDesc->Reference.Node;
444             }
445 
446             /* All "References" point to a NS node */
447 
448             if (ACPI_GET_DESCRIPTOR_TYPE (Node) != ACPI_DESC_TYPE_NAMED)
449             {
450                 ACPI_ERROR ((AE_INFO,
451                     "Not a namespace node %p [%s]",
452                     Node, AcpiUtGetDescriptorName (Node)));
453                 return_ACPI_STATUS (AE_AML_INTERNAL);
454             }
455 
456             /* Get the attached object */
457 
458             ObjDesc = AcpiNsGetAttachedObject (Node);
459             if (!ObjDesc)
460             {
461                 /* No object, use the NS node type */
462 
463                 Type = AcpiNsGetType (Node);
464                 goto Exit;
465             }
466 
467             /* Check for circular references */
468 
469             if (ObjDesc == Operand)
470             {
471                 return_ACPI_STATUS (AE_AML_CIRCULAR_REFERENCE);
472             }
473             break;
474 
475         case ACPI_REFCLASS_INDEX:
476 
477             /* Get the type of this reference (index into another object) */
478 
479             Type = ObjDesc->Reference.TargetType;
480             if (Type != ACPI_TYPE_PACKAGE)
481             {
482                 goto Exit;
483             }
484 
485             /*
486              * The main object is a package, we want to get the type
487              * of the individual package element that is referenced by
488              * the index.
489              *
490              * This could of course in turn be another reference object.
491              */
492             ObjDesc = *(ObjDesc->Reference.Where);
493             if (!ObjDesc)
494             {
495                 /* NULL package elements are allowed */
496 
497                 Type = 0; /* Uninitialized */
498                 goto Exit;
499             }
500             break;
501 
502         case ACPI_REFCLASS_TABLE:
503 
504             Type = ACPI_TYPE_DDB_HANDLE;
505             goto Exit;
506 
507         case ACPI_REFCLASS_LOCAL:
508         case ACPI_REFCLASS_ARG:
509 
510             if (ReturnDesc)
511             {
512                 Status = AcpiDsMethodDataGetValue (ObjDesc->Reference.Class,
513                     ObjDesc->Reference.Value, WalkState, &ObjDesc);
514                 if (ACPI_FAILURE (Status))
515                 {
516                     return_ACPI_STATUS (Status);
517                 }
518                 AcpiUtRemoveReference (ObjDesc);
519             }
520             else
521             {
522                 Status = AcpiDsMethodDataGetNode (ObjDesc->Reference.Class,
523                     ObjDesc->Reference.Value, WalkState, &Node);
524                 if (ACPI_FAILURE (Status))
525                 {
526                     return_ACPI_STATUS (Status);
527                 }
528 
529                 ObjDesc = AcpiNsGetAttachedObject (Node);
530                 if (!ObjDesc)
531                 {
532                     Type = ACPI_TYPE_ANY;
533                     goto Exit;
534                 }
535             }
536             break;
537 
538         case ACPI_REFCLASS_DEBUG:
539 
540             /* The Debug Object is of type "DebugObject" */
541 
542             Type = ACPI_TYPE_DEBUG_OBJECT;
543             goto Exit;
544 
545         default:
546 
547             ACPI_ERROR ((AE_INFO,
548                 "Unknown Reference Class 0x%2.2X",
549                 ObjDesc->Reference.Class));
550             return_ACPI_STATUS (AE_AML_INTERNAL);
551         }
552     }
553 
554     /*
555      * Now we are guaranteed to have an object that has not been created
556      * via the RefOf or Index operators.
557      */
558     Type = ObjDesc->Common.Type;
559 
560 
561 Exit:
562     /* Convert internal types to external types */
563 
564     switch (Type)
565     {
566     case ACPI_TYPE_LOCAL_REGION_FIELD:
567     case ACPI_TYPE_LOCAL_BANK_FIELD:
568     case ACPI_TYPE_LOCAL_INDEX_FIELD:
569 
570         Type = ACPI_TYPE_FIELD_UNIT;
571         break;
572 
573     case ACPI_TYPE_LOCAL_SCOPE:
574 
575         /* Per ACPI Specification, Scope is untyped */
576 
577         Type = ACPI_TYPE_ANY;
578         break;
579 
580     default:
581 
582         /* No change to Type required */
583 
584         break;
585     }
586 
587     *ReturnType = Type;
588     if (ReturnDesc)
589     {
590         *ReturnDesc = ObjDesc;
591     }
592     return_ACPI_STATUS (AE_OK);
593 }
594