xref: /freebsd/sys/contrib/dev/acpica/compiler/aslxref.c (revision 595e514d0df2bac5b813d35f83e32875dbf16a83)
1 /******************************************************************************
2  *
3  * Module Name: aslxref - Namespace cross-reference
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2013, 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 
45 #include <contrib/dev/acpica/compiler/aslcompiler.h>
46 #include "aslcompiler.y.h"
47 #include <contrib/dev/acpica/include/acparser.h>
48 #include <contrib/dev/acpica/include/amlcode.h>
49 #include <contrib/dev/acpica/include/acnamesp.h>
50 #include <contrib/dev/acpica/include/acdispat.h>
51 
52 
53 #define _COMPONENT          ACPI_COMPILER
54         ACPI_MODULE_NAME    ("aslxref")
55 
56 /* Local prototypes */
57 
58 static ACPI_STATUS
59 XfNamespaceLocateBegin (
60     ACPI_PARSE_OBJECT       *Op,
61     UINT32                  Level,
62     void                    *Context);
63 
64 static ACPI_STATUS
65 XfNamespaceLocateEnd (
66     ACPI_PARSE_OBJECT       *Op,
67     UINT32                  Level,
68     void                    *Context);
69 
70 static BOOLEAN
71 XfObjectExists (
72     char                    *Name);
73 
74 static ACPI_STATUS
75 XfCompareOneNamespaceObject (
76     ACPI_HANDLE             ObjHandle,
77     UINT32                  Level,
78     void                    *Context,
79     void                    **ReturnValue);
80 
81 static void
82 XfCheckFieldRange (
83     ACPI_PARSE_OBJECT       *Op,
84     UINT32                  RegionBitLength,
85     UINT32                  FieldBitOffset,
86     UINT32                  FieldBitLength,
87     UINT32                  AccessBitWidth);
88 
89 
90 /*******************************************************************************
91  *
92  * FUNCTION:    XfCrossReferenceNamespace
93  *
94  * PARAMETERS:  None
95  *
96  * RETURN:      Status
97  *
98  * DESCRIPTION: Perform a cross reference check of the parse tree against the
99  *              namespace. Every named referenced within the parse tree
100  *              should be get resolved with a namespace lookup. If not, the
101  *              original reference in the ASL code is invalid -- i.e., refers
102  *              to a non-existent object.
103  *
104  * NOTE:  The ASL "External" operator causes the name to be inserted into the
105  *        namespace so that references to the external name will be resolved
106  *        correctly here.
107  *
108  ******************************************************************************/
109 
110 ACPI_STATUS
111 XfCrossReferenceNamespace (
112     void)
113 {
114     ACPI_WALK_STATE         *WalkState;
115 
116 
117     DbgPrint (ASL_DEBUG_OUTPUT, "\nCross referencing namespace\n\n");
118 
119     /*
120      * Create a new walk state for use when looking up names
121      * within the namespace (Passed as context to the callbacks)
122      */
123     WalkState = AcpiDsCreateWalkState (0, NULL, NULL, NULL);
124     if (!WalkState)
125     {
126         return (AE_NO_MEMORY);
127     }
128 
129     /* Walk the entire parse tree */
130 
131     TrWalkParseTree (RootNode, ASL_WALK_VISIT_TWICE, XfNamespaceLocateBegin,
132                         XfNamespaceLocateEnd, WalkState);
133     return (AE_OK);
134 }
135 
136 
137 /*******************************************************************************
138  *
139  * FUNCTION:    XfObjectExists
140  *
141  * PARAMETERS:  Name            - 4 char ACPI name
142  *
143  * RETURN:      TRUE if name exists in namespace
144  *
145  * DESCRIPTION: Walk the namespace to find an object
146  *
147  ******************************************************************************/
148 
149 static BOOLEAN
150 XfObjectExists (
151     char                    *Name)
152 {
153     ACPI_STATUS             Status;
154 
155 
156     /* Walk entire namespace from the supplied root */
157 
158     Status = AcpiNsWalkNamespace (ACPI_TYPE_ANY, ACPI_ROOT_OBJECT,
159                 ACPI_UINT32_MAX, FALSE, XfCompareOneNamespaceObject, NULL,
160                 Name, NULL);
161     if (Status == AE_CTRL_TRUE)
162     {
163         /* At least one instance of the name was found */
164 
165         return (TRUE);
166     }
167 
168     return (FALSE);
169 }
170 
171 
172 /*******************************************************************************
173  *
174  * FUNCTION:    XfCompareOneNamespaceObject
175  *
176  * PARAMETERS:  ACPI_WALK_CALLBACK
177  *
178  * RETURN:      Status
179  *
180  * DESCRIPTION: Compare name of one object.
181  *
182  ******************************************************************************/
183 
184 static ACPI_STATUS
185 XfCompareOneNamespaceObject (
186     ACPI_HANDLE             ObjHandle,
187     UINT32                  Level,
188     void                    *Context,
189     void                    **ReturnValue)
190 {
191     ACPI_NAMESPACE_NODE     *Node = (ACPI_NAMESPACE_NODE *) ObjHandle;
192 
193 
194     /* Simply check the name */
195 
196     if (*((UINT32 *) (Context)) == Node->Name.Integer)
197     {
198         /* Abort walk if we found one instance */
199 
200         return (AE_CTRL_TRUE);
201     }
202 
203     return (AE_OK);
204 }
205 
206 
207 /*******************************************************************************
208  *
209  * FUNCTION:    XfCheckFieldRange
210  *
211  * PARAMETERS:  RegionBitLength     - Length of entire parent region
212  *              FieldBitOffset      - Start of the field unit (within region)
213  *              FieldBitLength      - Entire length of field unit
214  *              AccessBitWidth      - Access width of the field unit
215  *
216  * RETURN:      None
217  *
218  * DESCRIPTION: Check one field unit to make sure it fits in the parent
219  *              op region.
220  *
221  * Note: AccessBitWidth must be either 8,16,32, or 64
222  *
223  ******************************************************************************/
224 
225 static void
226 XfCheckFieldRange (
227     ACPI_PARSE_OBJECT       *Op,
228     UINT32                  RegionBitLength,
229     UINT32                  FieldBitOffset,
230     UINT32                  FieldBitLength,
231     UINT32                  AccessBitWidth)
232 {
233     UINT32                  FieldEndBitOffset;
234 
235 
236     /*
237      * Check each field unit against the region size. The entire
238      * field unit (start offset plus length) must fit within the
239      * region.
240      */
241     FieldEndBitOffset = FieldBitOffset + FieldBitLength;
242 
243     if (FieldEndBitOffset > RegionBitLength)
244     {
245         /* Field definition itself is beyond the end-of-region */
246 
247         AslError (ASL_ERROR, ASL_MSG_FIELD_UNIT_OFFSET, Op, NULL);
248         return;
249     }
250 
251     /*
252      * Now check that the field plus AccessWidth doesn't go beyond
253      * the end-of-region. Assumes AccessBitWidth is a power of 2
254      */
255     FieldEndBitOffset = ACPI_ROUND_UP (FieldEndBitOffset, AccessBitWidth);
256 
257     if (FieldEndBitOffset > RegionBitLength)
258     {
259         /* Field definition combined with the access is beyond EOR */
260 
261         AslError (ASL_ERROR, ASL_MSG_FIELD_UNIT_ACCESS_WIDTH, Op, NULL);
262     }
263 }
264 
265 /*******************************************************************************
266  *
267  * FUNCTION:    XfNamespaceLocateBegin
268  *
269  * PARAMETERS:  ASL_WALK_CALLBACK
270  *
271  * RETURN:      Status
272  *
273  * DESCRIPTION: Descending callback used during cross-reference. For named
274  *              object references, attempt to locate the name in the
275  *              namespace.
276  *
277  * NOTE: ASL references to named fields within resource descriptors are
278  *       resolved to integer values here. Therefore, this step is an
279  *       important part of the code generation. We don't know that the
280  *       name refers to a resource descriptor until now.
281  *
282  ******************************************************************************/
283 
284 static ACPI_STATUS
285 XfNamespaceLocateBegin (
286     ACPI_PARSE_OBJECT       *Op,
287     UINT32                  Level,
288     void                    *Context)
289 {
290     ACPI_WALK_STATE         *WalkState = (ACPI_WALK_STATE *) Context;
291     ACPI_NAMESPACE_NODE     *Node;
292     ACPI_STATUS             Status;
293     ACPI_OBJECT_TYPE        ObjectType;
294     char                    *Path;
295     UINT8                   PassedArgs;
296     ACPI_PARSE_OBJECT       *NextOp;
297     ACPI_PARSE_OBJECT       *OwningOp;
298     ACPI_PARSE_OBJECT       *SpaceIdOp;
299     UINT32                  MinimumLength;
300     UINT32                  Offset;
301     UINT32                  FieldBitLength;
302     UINT32                  TagBitLength;
303     UINT8                   Message = 0;
304     const ACPI_OPCODE_INFO  *OpInfo;
305     UINT32                  Flags;
306 
307 
308     ACPI_FUNCTION_TRACE_PTR (XfNamespaceLocateBegin, Op);
309 
310     /*
311      * If this node is the actual declaration of a name
312      * [such as the XXXX name in "Method (XXXX)"],
313      * we are not interested in it here. We only care about names that are
314      * references to other objects within the namespace and the parent objects
315      * of name declarations
316      */
317     if (Op->Asl.CompileFlags & NODE_IS_NAME_DECLARATION)
318     {
319         return (AE_OK);
320     }
321 
322     /* We are only interested in opcodes that have an associated name */
323 
324     OpInfo = AcpiPsGetOpcodeInfo (Op->Asl.AmlOpcode);
325 
326     if ((!(OpInfo->Flags & AML_NAMED)) &&
327         (!(OpInfo->Flags & AML_CREATE)) &&
328         (Op->Asl.ParseOpcode != PARSEOP_NAMESTRING) &&
329         (Op->Asl.ParseOpcode != PARSEOP_NAMESEG)    &&
330         (Op->Asl.ParseOpcode != PARSEOP_METHODCALL))
331     {
332         return (AE_OK);
333     }
334 
335     /*
336      * One special case: CondRefOf operator - we don't care if the name exists
337      * or not at this point, just ignore it, the point of the operator is to
338      * determine if the name exists at runtime.
339      */
340     if ((Op->Asl.Parent) &&
341         (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_CONDREFOF))
342     {
343         return (AE_OK);
344     }
345 
346     /*
347      * We must enable the "search-to-root" for single NameSegs, but
348      * we have to be very careful about opening up scopes
349      */
350     Flags = ACPI_NS_SEARCH_PARENT;
351     if ((Op->Asl.ParseOpcode == PARSEOP_NAMESTRING) ||
352         (Op->Asl.ParseOpcode == PARSEOP_NAMESEG)    ||
353         (Op->Asl.ParseOpcode == PARSEOP_METHODCALL))
354     {
355         /*
356          * These are name references, do not push the scope stack
357          * for them.
358          */
359         Flags |= ACPI_NS_DONT_OPEN_SCOPE;
360     }
361 
362     /* Get the NamePath from the appropriate place */
363 
364     if (OpInfo->Flags & AML_NAMED)
365     {
366         /* For nearly all NAMED operators, the name reference is the first child */
367 
368         Path = Op->Asl.Child->Asl.Value.String;
369         if (Op->Asl.AmlOpcode == AML_ALIAS_OP)
370         {
371             /*
372              * ALIAS is the only oddball opcode, the name declaration
373              * (alias name) is the second operand
374              */
375             Path = Op->Asl.Child->Asl.Next->Asl.Value.String;
376         }
377     }
378     else if (OpInfo->Flags & AML_CREATE)
379     {
380         /* Name must appear as the last parameter */
381 
382         NextOp = Op->Asl.Child;
383         while (!(NextOp->Asl.CompileFlags & NODE_IS_NAME_DECLARATION))
384         {
385             NextOp = NextOp->Asl.Next;
386         }
387         Path = NextOp->Asl.Value.String;
388     }
389     else
390     {
391         Path = Op->Asl.Value.String;
392     }
393 
394     ObjectType = AslMapNamedOpcodeToDataType (Op->Asl.AmlOpcode);
395     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
396         "Type=%s\n", AcpiUtGetTypeName (ObjectType)));
397 
398     /*
399      * Lookup the name in the namespace. Name must exist at this point, or it
400      * is an invalid reference.
401      *
402      * The namespace is also used as a lookup table for references to resource
403      * descriptors and the fields within them.
404      */
405     Gbl_NsLookupCount++;
406 
407     Status = AcpiNsLookup (WalkState->ScopeInfo, Path, ObjectType,
408                 ACPI_IMODE_EXECUTE, Flags, WalkState, &(Node));
409     if (ACPI_FAILURE (Status))
410     {
411         if (Status == AE_NOT_FOUND)
412         {
413             /*
414              * We didn't find the name reference by path -- we can qualify this
415              * a little better before we print an error message
416              */
417             if (strlen (Path) == ACPI_NAME_SIZE)
418             {
419                 /* A simple, one-segment ACPI name */
420 
421                 if (XfObjectExists (Path))
422                 {
423                     /*
424                      * There exists such a name, but we couldn't get to it
425                      * from this scope
426                      */
427                     AslError (ASL_ERROR, ASL_MSG_NOT_REACHABLE, Op,
428                         Op->Asl.ExternalName);
429                 }
430                 else
431                 {
432                     /* The name doesn't exist, period */
433 
434                     AslError (ASL_ERROR, ASL_MSG_NOT_EXIST,
435                         Op, Op->Asl.ExternalName);
436                 }
437             }
438             else
439             {
440                 /* Check for a fully qualified path */
441 
442                 if (Path[0] == AML_ROOT_PREFIX)
443                 {
444                     /* Gave full path, the object does not exist */
445 
446                     AslError (ASL_ERROR, ASL_MSG_NOT_EXIST, Op,
447                         Op->Asl.ExternalName);
448                 }
449                 else
450                 {
451                     /*
452                      * We can't tell whether it doesn't exist or just
453                      * can't be reached.
454                      */
455                     AslError (ASL_ERROR, ASL_MSG_NOT_FOUND, Op,
456                         Op->Asl.ExternalName);
457                 }
458             }
459 
460             Status = AE_OK;
461         }
462         return (Status);
463     }
464 
465     /* Check for a reference vs. name declaration */
466 
467     if (!(OpInfo->Flags & AML_NAMED) &&
468         !(OpInfo->Flags & AML_CREATE))
469     {
470         /* This node has been referenced, mark it for reference check */
471 
472         Node->Flags |= ANOBJ_IS_REFERENCED;
473     }
474 
475     /* Attempt to optimize the NamePath */
476 
477     OptOptimizeNamePath (Op, OpInfo->Flags, WalkState, Path, Node);
478 
479     /*
480      * 1) Dereference an alias (A name reference that is an alias)
481      *    Aliases are not nested, the alias always points to the final object
482      */
483     if ((Op->Asl.ParseOpcode != PARSEOP_ALIAS) &&
484         (Node->Type == ACPI_TYPE_LOCAL_ALIAS))
485     {
486         /* This node points back to the original PARSEOP_ALIAS */
487 
488         NextOp = Node->Op;
489 
490         /* The first child is the alias target op */
491 
492         NextOp = NextOp->Asl.Child;
493 
494         /* That in turn points back to original target alias node */
495 
496         if (NextOp->Asl.Node)
497         {
498             Node = NextOp->Asl.Node;
499         }
500 
501         /* Else - forward reference to alias, will be resolved later */
502     }
503 
504     /* 2) Check for a reference to a resource descriptor */
505 
506     if ((Node->Type == ACPI_TYPE_LOCAL_RESOURCE_FIELD) ||
507         (Node->Type == ACPI_TYPE_LOCAL_RESOURCE))
508     {
509         /*
510          * This was a reference to a field within a resource descriptor.
511          * Extract the associated field offset (either a bit or byte
512          * offset depending on the field type) and change the named
513          * reference into an integer for AML code generation
514          */
515         Offset = Node->Value;
516         TagBitLength = Node->Length;
517 
518         /*
519          * If a field is being created, generate the length (in bits) of
520          * the field. Note: Opcodes other than CreateXxxField and Index
521          * can come through here. For other opcodes, we just need to
522          * convert the resource tag reference to an integer offset.
523          */
524         switch (Op->Asl.Parent->Asl.AmlOpcode)
525         {
526         case AML_CREATE_FIELD_OP: /* Variable "Length" field, in bits */
527             /*
528              * We know the length operand is an integer constant because
529              * we know that it contains a reference to a resource
530              * descriptor tag.
531              */
532             FieldBitLength = (UINT32) Op->Asl.Next->Asl.Value.Integer;
533             break;
534 
535         case AML_CREATE_BIT_FIELD_OP:
536 
537             FieldBitLength = 1;
538             break;
539 
540         case AML_CREATE_BYTE_FIELD_OP:
541         case AML_INDEX_OP:
542 
543             FieldBitLength = 8;
544             break;
545 
546         case AML_CREATE_WORD_FIELD_OP:
547 
548             FieldBitLength = 16;
549             break;
550 
551         case AML_CREATE_DWORD_FIELD_OP:
552 
553             FieldBitLength = 32;
554             break;
555 
556         case AML_CREATE_QWORD_FIELD_OP:
557 
558             FieldBitLength = 64;
559             break;
560 
561         default:
562 
563             FieldBitLength = 0;
564             break;
565         }
566 
567         /* Check the field length against the length of the resource tag */
568 
569         if (FieldBitLength)
570         {
571             if (TagBitLength < FieldBitLength)
572             {
573                 Message = ASL_MSG_TAG_SMALLER;
574             }
575             else if (TagBitLength > FieldBitLength)
576             {
577                 Message = ASL_MSG_TAG_LARGER;
578             }
579 
580             if (Message)
581             {
582                 sprintf (MsgBuffer, "Size mismatch, Tag: %u bit%s, Field: %u bit%s",
583                     TagBitLength, (TagBitLength > 1) ? "s" : "",
584                     FieldBitLength, (FieldBitLength > 1) ? "s" : "");
585 
586                 AslError (ASL_WARNING, Message, Op, MsgBuffer);
587             }
588         }
589 
590         /* Convert the BitOffset to a ByteOffset for certain opcodes */
591 
592         switch (Op->Asl.Parent->Asl.AmlOpcode)
593         {
594         case AML_CREATE_BYTE_FIELD_OP:
595         case AML_CREATE_WORD_FIELD_OP:
596         case AML_CREATE_DWORD_FIELD_OP:
597         case AML_CREATE_QWORD_FIELD_OP:
598         case AML_INDEX_OP:
599 
600             Offset = ACPI_DIV_8 (Offset);
601             break;
602 
603         default:
604 
605             break;
606         }
607 
608         /* Now convert this node to an integer whose value is the field offset */
609 
610         Op->Asl.AmlLength = 0;
611         Op->Asl.ParseOpcode = PARSEOP_INTEGER;
612         Op->Asl.Value.Integer = (UINT64) Offset;
613         Op->Asl.CompileFlags |= NODE_IS_RESOURCE_FIELD;
614 
615         OpcGenerateAmlOpcode (Op);
616     }
617 
618     /* 3) Check for a method invocation */
619 
620     else if ((((Op->Asl.ParseOpcode == PARSEOP_NAMESTRING) || (Op->Asl.ParseOpcode == PARSEOP_NAMESEG)) &&
621                 (Node->Type == ACPI_TYPE_METHOD) &&
622                 (Op->Asl.Parent) &&
623                 (Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_METHOD))   ||
624 
625                 (Op->Asl.ParseOpcode == PARSEOP_METHODCALL))
626     {
627 
628         /*
629          * A reference to a method within one of these opcodes is not an
630          * invocation of the method, it is simply a reference to the method.
631          */
632         if ((Op->Asl.Parent) &&
633            ((Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_REFOF)      ||
634             (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_DEREFOF)    ||
635             (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_OBJECTTYPE)))
636         {
637             return (AE_OK);
638         }
639         /*
640          * There are two types of method invocation:
641          * 1) Invocation with arguments -- the parser recognizes this
642          *    as a METHODCALL.
643          * 2) Invocation with no arguments --the parser cannot determine that
644          *    this is a method invocation, therefore we have to figure it out
645          *    here.
646          */
647         if (Node->Type != ACPI_TYPE_METHOD)
648         {
649             sprintf (MsgBuffer, "%s is a %s",
650                     Op->Asl.ExternalName, AcpiUtGetTypeName (Node->Type));
651 
652             AslError (ASL_ERROR, ASL_MSG_NOT_METHOD, Op, MsgBuffer);
653             return (AE_OK);
654         }
655 
656         /* Save the method node in the caller's op */
657 
658         Op->Asl.Node = Node;
659         if (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_CONDREFOF)
660         {
661             return (AE_OK);
662         }
663 
664         /*
665          * This is a method invocation, with or without arguments.
666          * Count the number of arguments, each appears as a child
667          * under the parent node
668          */
669         Op->Asl.ParseOpcode = PARSEOP_METHODCALL;
670         UtSetParseOpName (Op);
671 
672         PassedArgs = 0;
673         NextOp     = Op->Asl.Child;
674 
675         while (NextOp)
676         {
677             PassedArgs++;
678             NextOp = NextOp->Asl.Next;
679         }
680 
681         if (Node->Value != ASL_EXTERNAL_METHOD)
682         {
683             /*
684              * Check the parsed arguments with the number expected by the
685              * method declaration itself
686              */
687             if (PassedArgs != Node->Value)
688             {
689                 sprintf (MsgBuffer, "%s requires %u", Op->Asl.ExternalName,
690                             Node->Value);
691 
692                 if (PassedArgs < Node->Value)
693                 {
694                     AslError (ASL_ERROR, ASL_MSG_ARG_COUNT_LO, Op, MsgBuffer);
695                 }
696                 else
697                 {
698                     AslError (ASL_ERROR, ASL_MSG_ARG_COUNT_HI, Op, MsgBuffer);
699                 }
700             }
701         }
702     }
703 
704     /* 4) Check for an ASL Field definition */
705 
706     else if ((Op->Asl.Parent) &&
707             ((Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_FIELD)     ||
708              (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_BANKFIELD)))
709     {
710         /*
711          * Offset checking for fields. If the parent operation region has a
712          * constant length (known at compile time), we can check fields
713          * defined in that region against the region length. This will catch
714          * fields and field units that cannot possibly fit within the region.
715          *
716          * Note: Index fields do not directly reference an operation region,
717          * thus they are not included in this check.
718          */
719         if (Op == Op->Asl.Parent->Asl.Child)
720         {
721             /*
722              * This is the first child of the field node, which is
723              * the name of the region. Get the parse node for the
724              * region -- which contains the length of the region.
725              */
726             OwningOp = Node->Op;
727             Op->Asl.Parent->Asl.ExtraValue =
728                 ACPI_MUL_8 ((UINT32) OwningOp->Asl.Value.Integer);
729 
730             /* Examine the field access width */
731 
732             switch ((UINT8) Op->Asl.Parent->Asl.Value.Integer)
733             {
734             case AML_FIELD_ACCESS_ANY:
735             case AML_FIELD_ACCESS_BYTE:
736             case AML_FIELD_ACCESS_BUFFER:
737             default:
738 
739                 MinimumLength = 1;
740                 break;
741 
742             case AML_FIELD_ACCESS_WORD:
743 
744                 MinimumLength = 2;
745                 break;
746 
747             case AML_FIELD_ACCESS_DWORD:
748 
749                 MinimumLength = 4;
750                 break;
751 
752             case AML_FIELD_ACCESS_QWORD:
753 
754                 MinimumLength = 8;
755                 break;
756             }
757 
758             /*
759              * Is the region at least as big as the access width?
760              * Note: DataTableRegions have 0 length
761              */
762             if (((UINT32) OwningOp->Asl.Value.Integer) &&
763                 ((UINT32) OwningOp->Asl.Value.Integer < MinimumLength))
764             {
765                 AslError (ASL_ERROR, ASL_MSG_FIELD_ACCESS_WIDTH, Op, NULL);
766             }
767 
768             /*
769              * Check EC/CMOS/SMBUS fields to make sure that the correct
770              * access type is used (BYTE for EC/CMOS, BUFFER for SMBUS)
771              */
772             SpaceIdOp = OwningOp->Asl.Child->Asl.Next;
773             switch ((UINT32) SpaceIdOp->Asl.Value.Integer)
774             {
775             case ACPI_ADR_SPACE_EC:
776             case ACPI_ADR_SPACE_CMOS:
777             case ACPI_ADR_SPACE_GPIO:
778 
779                 if ((UINT8) Op->Asl.Parent->Asl.Value.Integer != AML_FIELD_ACCESS_BYTE)
780                 {
781                     AslError (ASL_ERROR, ASL_MSG_REGION_BYTE_ACCESS, Op, NULL);
782                 }
783                 break;
784 
785             case ACPI_ADR_SPACE_SMBUS:
786             case ACPI_ADR_SPACE_IPMI:
787             case ACPI_ADR_SPACE_GSBUS:
788 
789                 if ((UINT8) Op->Asl.Parent->Asl.Value.Integer != AML_FIELD_ACCESS_BUFFER)
790                 {
791                     AslError (ASL_ERROR, ASL_MSG_REGION_BUFFER_ACCESS, Op, NULL);
792                 }
793                 break;
794 
795             default:
796 
797                 /* Nothing to do for other address spaces */
798 
799                 break;
800             }
801         }
802         else
803         {
804             /*
805              * This is one element of the field list. Check to make sure
806              * that it does not go beyond the end of the parent operation region.
807              *
808              * In the code below:
809              *    Op->Asl.Parent->Asl.ExtraValue      - Region Length (bits)
810              *    Op->Asl.ExtraValue                  - Field start offset (bits)
811              *    Op->Asl.Child->Asl.Value.Integer32  - Field length (bits)
812              *    Op->Asl.Child->Asl.ExtraValue       - Field access width (bits)
813              */
814             if (Op->Asl.Parent->Asl.ExtraValue && Op->Asl.Child)
815             {
816                 XfCheckFieldRange (Op,
817                             Op->Asl.Parent->Asl.ExtraValue,
818                             Op->Asl.ExtraValue,
819                             (UINT32) Op->Asl.Child->Asl.Value.Integer,
820                             Op->Asl.Child->Asl.ExtraValue);
821             }
822         }
823     }
824 
825     Op->Asl.Node = Node;
826     return (Status);
827 }
828 
829 
830 /*******************************************************************************
831  *
832  * FUNCTION:    XfNamespaceLocateEnd
833  *
834  * PARAMETERS:  ASL_WALK_CALLBACK
835  *
836  * RETURN:      Status
837  *
838  * DESCRIPTION: Ascending callback used during cross reference. We only
839  *              need to worry about scope management here.
840  *
841  ******************************************************************************/
842 
843 static ACPI_STATUS
844 XfNamespaceLocateEnd (
845     ACPI_PARSE_OBJECT       *Op,
846     UINT32                  Level,
847     void                    *Context)
848 {
849     ACPI_WALK_STATE         *WalkState = (ACPI_WALK_STATE *) Context;
850     const ACPI_OPCODE_INFO  *OpInfo;
851 
852 
853     ACPI_FUNCTION_TRACE (XfNamespaceLocateEnd);
854 
855 
856     /* We are only interested in opcodes that have an associated name */
857 
858     OpInfo = AcpiPsGetOpcodeInfo (Op->Asl.AmlOpcode);
859     if (!(OpInfo->Flags & AML_NAMED))
860     {
861         return (AE_OK);
862     }
863 
864     /* Not interested in name references, we did not open a scope for them */
865 
866     if ((Op->Asl.ParseOpcode == PARSEOP_NAMESTRING) ||
867         (Op->Asl.ParseOpcode == PARSEOP_NAMESEG)    ||
868         (Op->Asl.ParseOpcode == PARSEOP_METHODCALL))
869     {
870         return (AE_OK);
871     }
872 
873     /* Pop the scope stack if necessary */
874 
875     if (AcpiNsOpensScope (AslMapNamedOpcodeToDataType (Op->Asl.AmlOpcode)))
876     {
877 
878         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
879             "%s: Popping scope for Op %p\n",
880             AcpiUtGetTypeName (OpInfo->ObjectType), Op));
881 
882         (void) AcpiDsScopeStackPop (WalkState);
883     }
884 
885     return (AE_OK);
886 }
887