xref: /freebsd/sys/contrib/dev/acpica/compiler/aslxref.c (revision 5dae51da3da0cc94d17bd67b308fad304ebec7e0)
1 /******************************************************************************
2  *
3  * Module Name: aslxref - Namespace cross-reference
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2016, 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 <contrib/dev/acpica/compiler/aslcompiler.h>
45 #include "aslcompiler.y.h"
46 #include <contrib/dev/acpica/include/acparser.h>
47 #include <contrib/dev/acpica/include/amlcode.h>
48 #include <contrib/dev/acpica/include/acnamesp.h>
49 #include <contrib/dev/acpica/include/acdispat.h>
50 
51 
52 #define _COMPONENT          ACPI_COMPILER
53         ACPI_MODULE_NAME    ("aslxref")
54 
55 /* Local prototypes */
56 
57 static ACPI_STATUS
58 XfNamespaceLocateBegin (
59     ACPI_PARSE_OBJECT       *Op,
60     UINT32                  Level,
61     void                    *Context);
62 
63 static ACPI_STATUS
64 XfNamespaceLocateEnd (
65     ACPI_PARSE_OBJECT       *Op,
66     UINT32                  Level,
67     void                    *Context);
68 
69 static ACPI_PARSE_OBJECT *
70 XfGetParentMethod (
71     ACPI_PARSE_OBJECT       *Op);
72 
73 static BOOLEAN
74 XfObjectExists (
75     char                    *Name);
76 
77 static ACPI_STATUS
78 XfCompareOneNamespaceObject (
79     ACPI_HANDLE             ObjHandle,
80     UINT32                  Level,
81     void                    *Context,
82     void                    **ReturnValue);
83 
84 static void
85 XfCheckFieldRange (
86     ACPI_PARSE_OBJECT       *Op,
87     UINT32                  RegionBitLength,
88     UINT32                  FieldBitOffset,
89     UINT32                  FieldBitLength,
90     UINT32                  AccessBitWidth);
91 
92 #ifdef __UNDER_DEVELOPMENT
93 static ACPI_PARSE_OBJECT *
94 XfGetParentMethod (
95     ACPI_PARSE_OBJECT       *Op);
96 
97 static void
98 XfCheckIllegalReference (
99     ACPI_PARSE_OBJECT       *Op,
100     ACPI_NAMESPACE_NODE     *Node);
101 
102 static BOOLEAN
103 XfIsObjectParental (
104     ACPI_PARSE_OBJECT       *MethodOp1,
105     ACPI_PARSE_OBJECT       *MethodOp2);
106 #endif
107 
108 
109 /*******************************************************************************
110  *
111  * FUNCTION:    XfCrossReferenceNamespace
112  *
113  * PARAMETERS:  None
114  *
115  * RETURN:      Status
116  *
117  * DESCRIPTION: Perform a cross reference check of the parse tree against the
118  *              namespace. Every named referenced within the parse tree
119  *              should be get resolved with a namespace lookup. If not, the
120  *              original reference in the ASL code is invalid -- i.e., refers
121  *              to a non-existent object.
122  *
123  * NOTE:  The ASL "External" operator causes the name to be inserted into the
124  *        namespace so that references to the external name will be resolved
125  *        correctly here.
126  *
127  ******************************************************************************/
128 
129 ACPI_STATUS
130 XfCrossReferenceNamespace (
131     void)
132 {
133     ACPI_WALK_STATE         *WalkState;
134 
135 
136     /*
137      * Create a new walk state for use when looking up names
138      * within the namespace (Passed as context to the callbacks)
139      */
140     WalkState = AcpiDsCreateWalkState (0, NULL, NULL, NULL);
141     if (!WalkState)
142     {
143         return (AE_NO_MEMORY);
144     }
145 
146     /* Walk the entire parse tree */
147 
148     TrWalkParseTree (Gbl_ParseTreeRoot, ASL_WALK_VISIT_TWICE,
149         XfNamespaceLocateBegin, XfNamespaceLocateEnd, WalkState);
150 
151     ACPI_FREE (WalkState);
152     return (AE_OK);
153 }
154 
155 
156 /*******************************************************************************
157  *
158  * FUNCTION:    XfObjectExists
159  *
160  * PARAMETERS:  Name            - 4 char ACPI name
161  *
162  * RETURN:      TRUE if name exists in namespace
163  *
164  * DESCRIPTION: Walk the namespace to find an object
165  *
166  ******************************************************************************/
167 
168 static BOOLEAN
169 XfObjectExists (
170     char                    *Name)
171 {
172     ACPI_STATUS             Status;
173 
174 
175     /* Walk entire namespace from the supplied root */
176 
177     Status = AcpiNsWalkNamespace (ACPI_TYPE_ANY, ACPI_ROOT_OBJECT,
178         ACPI_UINT32_MAX, FALSE, XfCompareOneNamespaceObject, NULL,
179         Name, NULL);
180     if (Status == AE_CTRL_TRUE)
181     {
182         /* At least one instance of the name was found */
183 
184         return (TRUE);
185     }
186 
187     return (FALSE);
188 }
189 
190 
191 /*******************************************************************************
192  *
193  * FUNCTION:    XfCompareOneNamespaceObject
194  *
195  * PARAMETERS:  ACPI_WALK_CALLBACK
196  *
197  * RETURN:      Status
198  *
199  * DESCRIPTION: Compare name of one object.
200  *
201  ******************************************************************************/
202 
203 static ACPI_STATUS
204 XfCompareOneNamespaceObject (
205     ACPI_HANDLE             ObjHandle,
206     UINT32                  Level,
207     void                    *Context,
208     void                    **ReturnValue)
209 {
210     ACPI_NAMESPACE_NODE     *Node = (ACPI_NAMESPACE_NODE *) ObjHandle;
211 
212 
213     /* Simply check the name */
214 
215     if (*((UINT32 *) (Context)) == Node->Name.Integer)
216     {
217         /* Abort walk if we found one instance */
218 
219         return (AE_CTRL_TRUE);
220     }
221 
222     return (AE_OK);
223 }
224 
225 
226 /*******************************************************************************
227  *
228  * FUNCTION:    XfCheckFieldRange
229  *
230  * PARAMETERS:  RegionBitLength     - Length of entire parent region
231  *              FieldBitOffset      - Start of the field unit (within region)
232  *              FieldBitLength      - Entire length of field unit
233  *              AccessBitWidth      - Access width of the field unit
234  *
235  * RETURN:      None
236  *
237  * DESCRIPTION: Check one field unit to make sure it fits in the parent
238  *              op region.
239  *
240  * Note: AccessBitWidth must be either 8,16,32, or 64
241  *
242  ******************************************************************************/
243 
244 static void
245 XfCheckFieldRange (
246     ACPI_PARSE_OBJECT       *Op,
247     UINT32                  RegionBitLength,
248     UINT32                  FieldBitOffset,
249     UINT32                  FieldBitLength,
250     UINT32                  AccessBitWidth)
251 {
252     UINT32                  FieldEndBitOffset;
253 
254 
255     /*
256      * Check each field unit against the region size. The entire
257      * field unit (start offset plus length) must fit within the
258      * region.
259      */
260     FieldEndBitOffset = FieldBitOffset + FieldBitLength;
261 
262     if (FieldEndBitOffset > RegionBitLength)
263     {
264         /* Field definition itself is beyond the end-of-region */
265 
266         AslError (ASL_ERROR, ASL_MSG_FIELD_UNIT_OFFSET, Op, NULL);
267         return;
268     }
269 
270     /*
271      * Now check that the field plus AccessWidth doesn't go beyond
272      * the end-of-region. Assumes AccessBitWidth is a power of 2
273      */
274     FieldEndBitOffset = ACPI_ROUND_UP (FieldEndBitOffset, AccessBitWidth);
275 
276     if (FieldEndBitOffset > RegionBitLength)
277     {
278         /* Field definition combined with the access is beyond EOR */
279 
280         AslError (ASL_ERROR, ASL_MSG_FIELD_UNIT_ACCESS_WIDTH, Op, NULL);
281     }
282 }
283 
284 
285 /*******************************************************************************
286  *
287  * FUNCTION:    XfGetParentMethod
288  *
289  * PARAMETERS:  Op                      - Parse Op to be checked
290  *
291  * RETURN:      Control method Op if found. NULL otherwise
292  *
293  * DESCRIPTION: Find the control method parent of a parse op. Returns NULL if
294  *              the input Op is not within a control method.
295  *
296  ******************************************************************************/
297 
298 static ACPI_PARSE_OBJECT *
299 XfGetParentMethod (
300     ACPI_PARSE_OBJECT       *Op)
301 {
302     ACPI_PARSE_OBJECT       *NextOp;
303 
304 
305     NextOp = Op->Asl.Parent;
306     while (NextOp)
307     {
308         if (NextOp->Asl.AmlOpcode == AML_METHOD_OP)
309         {
310             return (NextOp);
311         }
312 
313         NextOp = NextOp->Asl.Parent;
314     }
315 
316     return (NULL); /* No parent method found */
317 }
318 
319 /*******************************************************************************
320  *
321  * FUNCTION:    XfNamespaceLocateBegin
322  *
323  * PARAMETERS:  ASL_WALK_CALLBACK
324  *
325  * RETURN:      Status
326  *
327  * DESCRIPTION: Descending callback used during cross-reference. For named
328  *              object references, attempt to locate the name in the
329  *              namespace.
330  *
331  * NOTE: ASL references to named fields within resource descriptors are
332  *       resolved to integer values here. Therefore, this step is an
333  *       important part of the code generation. We don't know that the
334  *       name refers to a resource descriptor until now.
335  *
336  ******************************************************************************/
337 
338 static ACPI_STATUS
339 XfNamespaceLocateBegin (
340     ACPI_PARSE_OBJECT       *Op,
341     UINT32                  Level,
342     void                    *Context)
343 {
344     ACPI_WALK_STATE         *WalkState = (ACPI_WALK_STATE *) Context;
345     ACPI_NAMESPACE_NODE     *Node;
346     ACPI_STATUS             Status;
347     ACPI_OBJECT_TYPE        ObjectType;
348     char                    *Path;
349     UINT8                   PassedArgs;
350     ACPI_PARSE_OBJECT       *NextOp;
351     ACPI_PARSE_OBJECT       *OwningOp;
352     ACPI_PARSE_OBJECT       *SpaceIdOp;
353     UINT32                  MinimumLength;
354     UINT32                  Offset;
355     UINT32                  FieldBitLength;
356     UINT32                  TagBitLength;
357     UINT8                   Message = 0;
358     const ACPI_OPCODE_INFO  *OpInfo;
359     UINT32                  Flags;
360     ASL_METHOD_LOCAL        *MethodLocals = NULL;
361     ASL_METHOD_LOCAL        *MethodArgs = NULL;
362     int                     RegisterNumber;
363     UINT32                  i;
364 
365 
366     ACPI_FUNCTION_TRACE_PTR (XfNamespaceLocateBegin, Op);
367 
368 
369     if ((Op->Asl.AmlOpcode == AML_METHOD_OP) && Op->Asl.Node)
370     {
371         Node = Op->Asl.Node;
372 
373         /* Support for method LocalX/ArgX analysis */
374 
375         if (!Node->MethodLocals)
376         {
377             /* Create local/arg info blocks */
378 
379             MethodLocals = UtLocalCalloc (
380                 sizeof (ASL_METHOD_LOCAL) * ACPI_METHOD_NUM_LOCALS);
381             Node->MethodLocals = MethodLocals;
382 
383             MethodArgs = UtLocalCalloc (
384                 sizeof (ASL_METHOD_LOCAL) * ACPI_METHOD_NUM_ARGS);
385             Node->MethodArgs = MethodArgs;
386 
387             /*
388              * Get the method argument count
389              * First, get the name node
390              */
391             NextOp = Op->Asl.Child;
392 
393             /* Get the NumArguments node */
394 
395             NextOp = NextOp->Asl.Next;
396             Node->ArgCount = (UINT8)
397                 (((UINT8) NextOp->Asl.Value.Integer) & 0x07);
398 
399             /* We will track all posible ArgXs */
400 
401             for (i = 0; i < ACPI_METHOD_NUM_ARGS; i++)
402             {
403                 if (i < Node->ArgCount)
404                 {
405                     /* Real Args are always "initialized" */
406 
407                     MethodArgs[i].Flags = ASL_ARG_INITIALIZED;
408                 }
409                 else
410                 {
411                     /* Other ArgXs can be used as locals */
412 
413                     MethodArgs[i].Flags = ASL_ARG_IS_LOCAL;
414                 }
415 
416                 MethodArgs[i].Op = Op;
417             }
418         }
419     }
420 
421     /*
422      * If this node is the actual declaration of a name
423      * [such as the XXXX name in "Method (XXXX)"],
424      * we are not interested in it here. We only care about names that are
425      * references to other objects within the namespace and the parent objects
426      * of name declarations
427      */
428     if (Op->Asl.CompileFlags & NODE_IS_NAME_DECLARATION)
429     {
430         return_ACPI_STATUS (AE_OK);
431     }
432 
433     OpInfo = AcpiPsGetOpcodeInfo (Op->Asl.AmlOpcode);
434 
435     /* Check method LocalX variables */
436 
437     if (OpInfo->Type == AML_TYPE_LOCAL_VARIABLE)
438     {
439         /* Find parent method Op */
440 
441         NextOp = XfGetParentMethod (Op);
442         if (!NextOp)
443         {
444             return_ACPI_STATUS (AE_OK);
445         }
446 
447         /* Get method node */
448 
449         Node = NextOp->Asl.Node;
450 
451         RegisterNumber = Op->Asl.AmlOpcode & 0x0007; /* 0x60 through 0x67 */
452         MethodLocals = Node->MethodLocals;
453 
454         if (Op->Asl.CompileFlags & NODE_IS_TARGET)
455         {
456             /* Local is being initialized */
457 
458             MethodLocals[RegisterNumber].Flags |= ASL_LOCAL_INITIALIZED;
459             MethodLocals[RegisterNumber].Op = Op;
460 
461             return_ACPI_STATUS (AE_OK);
462         }
463 
464         /* Mark this Local as referenced */
465 
466         MethodLocals[RegisterNumber].Flags |= ASL_LOCAL_REFERENCED;
467         MethodLocals[RegisterNumber].Op = Op;
468 
469         return_ACPI_STATUS (AE_OK);
470     }
471 
472     /* Check method ArgX variables */
473 
474     if (OpInfo->Type == AML_TYPE_METHOD_ARGUMENT)
475     {
476         /* Find parent method Op */
477 
478         NextOp = XfGetParentMethod (Op);
479         if (!NextOp)
480         {
481             return_ACPI_STATUS (AE_OK);
482         }
483 
484         /* Get method node */
485 
486         Node = NextOp->Asl.Node;
487 
488         /* Get Arg # */
489 
490         RegisterNumber = Op->Asl.AmlOpcode - AML_ARG0; /* 0x68 through 0x6F */
491         MethodArgs = Node->MethodArgs;
492 
493         if (Op->Asl.CompileFlags & NODE_IS_TARGET)
494         {
495             /* Arg is being initialized */
496 
497             MethodArgs[RegisterNumber].Flags |= ASL_ARG_INITIALIZED;
498             MethodArgs[RegisterNumber].Op = Op;
499 
500             return_ACPI_STATUS (AE_OK);
501         }
502 
503         /* Mark this Arg as referenced */
504 
505         MethodArgs[RegisterNumber].Flags |= ASL_ARG_REFERENCED;
506         MethodArgs[RegisterNumber].Op = Op;
507 
508         return_ACPI_STATUS (AE_OK);
509     }
510 
511     /*
512      * After method ArgX and LocalX, we are only interested in opcodes
513      * that have an associated name
514      */
515     if ((!(OpInfo->Flags & AML_NAMED)) &&
516         (!(OpInfo->Flags & AML_CREATE)) &&
517         (Op->Asl.ParseOpcode != PARSEOP_NAMESTRING) &&
518         (Op->Asl.ParseOpcode != PARSEOP_NAMESEG)    &&
519         (Op->Asl.ParseOpcode != PARSEOP_METHODCALL))
520     {
521         return_ACPI_STATUS (AE_OK);
522     }
523 
524     /*
525      * One special case: CondRefOf operator - we don't care if the name exists
526      * or not at this point, just ignore it, the point of the operator is to
527      * determine if the name exists at runtime.
528      */
529     if ((Op->Asl.Parent) &&
530         (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_CONDREFOF))
531     {
532         return_ACPI_STATUS (AE_OK);
533     }
534 
535     /*
536      * We must enable the "search-to-root" for single NameSegs, but
537      * we have to be very careful about opening up scopes
538      */
539     Flags = ACPI_NS_SEARCH_PARENT;
540     if ((Op->Asl.ParseOpcode == PARSEOP_NAMESTRING) ||
541         (Op->Asl.ParseOpcode == PARSEOP_NAMESEG)    ||
542         (Op->Asl.ParseOpcode == PARSEOP_METHODCALL))
543     {
544         /*
545          * These are name references, do not push the scope stack
546          * for them.
547          */
548         Flags |= ACPI_NS_DONT_OPEN_SCOPE;
549     }
550 
551     /* Get the NamePath from the appropriate place */
552 
553     if (OpInfo->Flags & AML_NAMED)
554     {
555         /* For nearly all NAMED operators, the name reference is the first child */
556 
557         Path = Op->Asl.Child->Asl.Value.String;
558         if (Op->Asl.AmlOpcode == AML_ALIAS_OP)
559         {
560             /*
561              * ALIAS is the only oddball opcode, the name declaration
562              * (alias name) is the second operand
563              */
564             Path = Op->Asl.Child->Asl.Next->Asl.Value.String;
565         }
566     }
567     else if (OpInfo->Flags & AML_CREATE)
568     {
569         /* Name must appear as the last parameter */
570 
571         NextOp = Op->Asl.Child;
572         while (!(NextOp->Asl.CompileFlags & NODE_IS_NAME_DECLARATION))
573         {
574             NextOp = NextOp->Asl.Next;
575         }
576 
577         Path = NextOp->Asl.Value.String;
578     }
579     else
580     {
581         Path = Op->Asl.Value.String;
582     }
583 
584     ObjectType = AslMapNamedOpcodeToDataType (Op->Asl.AmlOpcode);
585     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
586         "Type=%s\n", AcpiUtGetTypeName (ObjectType)));
587 
588     /*
589      * Lookup the name in the namespace. Name must exist at this point, or it
590      * is an invalid reference.
591      *
592      * The namespace is also used as a lookup table for references to resource
593      * descriptors and the fields within them.
594      */
595     Gbl_NsLookupCount++;
596 
597     Status = AcpiNsLookup (WalkState->ScopeInfo, Path, ObjectType,
598         ACPI_IMODE_EXECUTE, Flags, WalkState, &(Node));
599     if (ACPI_FAILURE (Status))
600     {
601         if (Status == AE_NOT_FOUND)
602         {
603             /*
604              * We didn't find the name reference by path -- we can qualify this
605              * a little better before we print an error message
606              */
607             if (strlen (Path) == ACPI_NAME_SIZE)
608             {
609                 /* A simple, one-segment ACPI name */
610 
611                 if (XfObjectExists (Path))
612                 {
613                     /*
614                      * There exists such a name, but we couldn't get to it
615                      * from this scope
616                      */
617                     AslError (ASL_ERROR, ASL_MSG_NOT_REACHABLE, Op,
618                         Op->Asl.ExternalName);
619                 }
620                 else
621                 {
622                     /* The name doesn't exist, period */
623 
624                     AslError (ASL_ERROR, ASL_MSG_NOT_EXIST,
625                         Op, Op->Asl.ExternalName);
626                 }
627             }
628             else
629             {
630                 /* Check for a fully qualified path */
631 
632                 if (Path[0] == AML_ROOT_PREFIX)
633                 {
634                     /* Gave full path, the object does not exist */
635 
636                     AslError (ASL_ERROR, ASL_MSG_NOT_EXIST, Op,
637                         Op->Asl.ExternalName);
638                 }
639                 else
640                 {
641                     /*
642                      * We can't tell whether it doesn't exist or just
643                      * can't be reached.
644                      */
645                     AslError (ASL_ERROR, ASL_MSG_NOT_FOUND, Op,
646                         Op->Asl.ExternalName);
647                 }
648             }
649 
650             Status = AE_OK;
651         }
652 
653         return_ACPI_STATUS (Status);
654     }
655 
656     /* Check for a reference vs. name declaration */
657 
658     if (!(OpInfo->Flags & AML_NAMED) &&
659         !(OpInfo->Flags & AML_CREATE))
660     {
661         /* This node has been referenced, mark it for reference check */
662 
663         Node->Flags |= ANOBJ_IS_REFERENCED;
664 
665 #ifdef __UNDER_DEVELOPMENT
666 
667         /* Check for an illegal reference */
668 
669         XfCheckIllegalReference (Op, Node);
670 #endif
671     }
672 
673     /* Attempt to optimize the NamePath */
674 
675     OptOptimizeNamePath (Op, OpInfo->Flags, WalkState, Path, Node);
676 
677     /*
678      * 1) Dereference an alias (A name reference that is an alias)
679      *    Aliases are not nested, the alias always points to the final object
680      */
681     if ((Op->Asl.ParseOpcode != PARSEOP_ALIAS) &&
682         (Node->Type == ACPI_TYPE_LOCAL_ALIAS))
683     {
684         /* This node points back to the original PARSEOP_ALIAS */
685 
686         NextOp = Node->Op;
687 
688         /* The first child is the alias target op */
689 
690         NextOp = NextOp->Asl.Child;
691 
692         /* That in turn points back to original target alias node */
693 
694         if (NextOp->Asl.Node)
695         {
696             Node = NextOp->Asl.Node;
697         }
698 
699         /* Else - forward reference to alias, will be resolved later */
700     }
701 
702     /* 2) Check for a reference to a resource descriptor */
703 
704     if ((Node->Type == ACPI_TYPE_LOCAL_RESOURCE_FIELD) ||
705         (Node->Type == ACPI_TYPE_LOCAL_RESOURCE))
706     {
707         /*
708          * This was a reference to a field within a resource descriptor.
709          * Extract the associated field offset (either a bit or byte
710          * offset depending on the field type) and change the named
711          * reference into an integer for AML code generation
712          */
713         Offset = Node->Value;
714         TagBitLength = Node->Length;
715 
716         /*
717          * If a field is being created, generate the length (in bits) of
718          * the field. Note: Opcodes other than CreateXxxField and Index
719          * can come through here. For other opcodes, we just need to
720          * convert the resource tag reference to an integer offset.
721          */
722         switch (Op->Asl.Parent->Asl.AmlOpcode)
723         {
724         case AML_CREATE_FIELD_OP: /* Variable "Length" field, in bits */
725             /*
726              * We know the length operand is an integer constant because
727              * we know that it contains a reference to a resource
728              * descriptor tag.
729              */
730             FieldBitLength = (UINT32) Op->Asl.Next->Asl.Value.Integer;
731             break;
732 
733         case AML_CREATE_BIT_FIELD_OP:
734 
735             FieldBitLength = 1;
736             break;
737 
738         case AML_CREATE_BYTE_FIELD_OP:
739         case AML_INDEX_OP:
740 
741             FieldBitLength = 8;
742             break;
743 
744         case AML_CREATE_WORD_FIELD_OP:
745 
746             FieldBitLength = 16;
747             break;
748 
749         case AML_CREATE_DWORD_FIELD_OP:
750 
751             FieldBitLength = 32;
752             break;
753 
754         case AML_CREATE_QWORD_FIELD_OP:
755 
756             FieldBitLength = 64;
757             break;
758 
759         default:
760 
761             FieldBitLength = 0;
762             break;
763         }
764 
765         /* Check the field length against the length of the resource tag */
766 
767         if (FieldBitLength)
768         {
769             if (TagBitLength < FieldBitLength)
770             {
771                 Message = ASL_MSG_TAG_SMALLER;
772             }
773             else if (TagBitLength > FieldBitLength)
774             {
775                 Message = ASL_MSG_TAG_LARGER;
776             }
777 
778             if (Message)
779             {
780                 sprintf (MsgBuffer,
781                     "Size mismatch, Tag: %u bit%s, Field: %u bit%s",
782                     TagBitLength, (TagBitLength > 1) ? "s" : "",
783                     FieldBitLength, (FieldBitLength > 1) ? "s" : "");
784 
785                 AslError (ASL_WARNING, Message, Op, MsgBuffer);
786             }
787         }
788 
789         /* Convert the BitOffset to a ByteOffset for certain opcodes */
790 
791         switch (Op->Asl.Parent->Asl.AmlOpcode)
792         {
793         case AML_CREATE_BYTE_FIELD_OP:
794         case AML_CREATE_WORD_FIELD_OP:
795         case AML_CREATE_DWORD_FIELD_OP:
796         case AML_CREATE_QWORD_FIELD_OP:
797         case AML_INDEX_OP:
798 
799             Offset = ACPI_DIV_8 (Offset);
800             break;
801 
802         default:
803 
804             break;
805         }
806 
807         /* Now convert this node to an integer whose value is the field offset */
808 
809         Op->Asl.AmlLength = 0;
810         Op->Asl.ParseOpcode = PARSEOP_INTEGER;
811         Op->Asl.Value.Integer = (UINT64) Offset;
812         Op->Asl.CompileFlags |= NODE_IS_RESOURCE_FIELD;
813 
814         OpcGenerateAmlOpcode (Op);
815     }
816 
817     /* 3) Check for a method invocation */
818 
819     else if ((((Op->Asl.ParseOpcode == PARSEOP_NAMESTRING) || (Op->Asl.ParseOpcode == PARSEOP_NAMESEG)) &&
820                 (Node->Type == ACPI_TYPE_METHOD) &&
821                 (Op->Asl.Parent) &&
822                 (Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_METHOD))   ||
823 
824                 (Op->Asl.ParseOpcode == PARSEOP_METHODCALL))
825     {
826         /*
827          * A reference to a method within one of these opcodes is not an
828          * invocation of the method, it is simply a reference to the method.
829          *
830          * September 2016: Removed DeRefOf from this list
831          */
832         if ((Op->Asl.Parent) &&
833             ((Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_REFOF)     ||
834             (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_PACKAGE)    ||
835             (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_VAR_PACKAGE)||
836             (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_OBJECTTYPE)))
837         {
838             return_ACPI_STATUS (AE_OK);
839         }
840 
841         /*
842          * There are two types of method invocation:
843          * 1) Invocation with arguments -- the parser recognizes this
844          *    as a METHODCALL.
845          * 2) Invocation with no arguments --the parser cannot determine that
846          *    this is a method invocation, therefore we have to figure it out
847          *    here.
848          */
849         if (Node->Type != ACPI_TYPE_METHOD)
850         {
851             sprintf (MsgBuffer, "%s is a %s",
852                 Op->Asl.ExternalName, AcpiUtGetTypeName (Node->Type));
853 
854             AslError (ASL_ERROR, ASL_MSG_NOT_METHOD, Op, MsgBuffer);
855             return_ACPI_STATUS (AE_OK);
856         }
857 
858         /* Save the method node in the caller's op */
859 
860         Op->Asl.Node = Node;
861         if (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_CONDREFOF)
862         {
863             return_ACPI_STATUS (AE_OK);
864         }
865 
866         /*
867          * This is a method invocation, with or without arguments.
868          * Count the number of arguments, each appears as a child
869          * under the parent node
870          */
871         Op->Asl.ParseOpcode = PARSEOP_METHODCALL;
872         UtSetParseOpName (Op);
873 
874         PassedArgs = 0;
875         NextOp = Op->Asl.Child;
876 
877         while (NextOp)
878         {
879             PassedArgs++;
880             NextOp = NextOp->Asl.Next;
881         }
882 
883         if (Node->Value != ASL_EXTERNAL_METHOD &&
884             Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_EXTERNAL)
885         {
886             /*
887              * Check the parsed arguments with the number expected by the
888              * method declaration itself
889              */
890             if (PassedArgs != Node->Value)
891             {
892                 sprintf (MsgBuffer, "%s requires %u", Op->Asl.ExternalName,
893                             Node->Value);
894 
895                 if (PassedArgs < Node->Value)
896                 {
897                     AslError (ASL_ERROR, ASL_MSG_ARG_COUNT_LO, Op, MsgBuffer);
898                 }
899                 else
900                 {
901                     AslError (ASL_ERROR, ASL_MSG_ARG_COUNT_HI, Op, MsgBuffer);
902                 }
903             }
904         }
905     }
906 
907     /* 4) Check for an ASL Field definition */
908 
909     else if ((Op->Asl.Parent) &&
910             ((Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_FIELD)     ||
911              (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_BANKFIELD)))
912     {
913         /*
914          * Offset checking for fields. If the parent operation region has a
915          * constant length (known at compile time), we can check fields
916          * defined in that region against the region length. This will catch
917          * fields and field units that cannot possibly fit within the region.
918          *
919          * Note: Index fields do not directly reference an operation region,
920          * thus they are not included in this check.
921          */
922         if (Op == Op->Asl.Parent->Asl.Child)
923         {
924             /*
925              * This is the first child of the field node, which is
926              * the name of the region. Get the parse node for the
927              * region -- which contains the length of the region.
928              */
929             OwningOp = Node->Op;
930             Op->Asl.Parent->Asl.ExtraValue =
931                 ACPI_MUL_8 ((UINT32) OwningOp->Asl.Value.Integer);
932 
933             /* Examine the field access width */
934 
935             switch ((UINT8) Op->Asl.Parent->Asl.Value.Integer)
936             {
937             case AML_FIELD_ACCESS_ANY:
938             case AML_FIELD_ACCESS_BYTE:
939             case AML_FIELD_ACCESS_BUFFER:
940             default:
941 
942                 MinimumLength = 1;
943                 break;
944 
945             case AML_FIELD_ACCESS_WORD:
946 
947                 MinimumLength = 2;
948                 break;
949 
950             case AML_FIELD_ACCESS_DWORD:
951 
952                 MinimumLength = 4;
953                 break;
954 
955             case AML_FIELD_ACCESS_QWORD:
956 
957                 MinimumLength = 8;
958                 break;
959             }
960 
961             /*
962              * Is the region at least as big as the access width?
963              * Note: DataTableRegions have 0 length
964              */
965             if (((UINT32) OwningOp->Asl.Value.Integer) &&
966                 ((UINT32) OwningOp->Asl.Value.Integer < MinimumLength))
967             {
968                 AslError (ASL_ERROR, ASL_MSG_FIELD_ACCESS_WIDTH, Op, NULL);
969             }
970 
971             /*
972              * Check EC/CMOS/SMBUS fields to make sure that the correct
973              * access type is used (BYTE for EC/CMOS, BUFFER for SMBUS)
974              */
975             SpaceIdOp = OwningOp->Asl.Child->Asl.Next;
976             switch ((UINT32) SpaceIdOp->Asl.Value.Integer)
977             {
978             case ACPI_ADR_SPACE_EC:
979             case ACPI_ADR_SPACE_CMOS:
980             case ACPI_ADR_SPACE_GPIO:
981 
982                 if ((UINT8) Op->Asl.Parent->Asl.Value.Integer !=
983                     AML_FIELD_ACCESS_BYTE)
984                 {
985                     AslError (ASL_ERROR, ASL_MSG_REGION_BYTE_ACCESS, Op, NULL);
986                 }
987                 break;
988 
989             case ACPI_ADR_SPACE_SMBUS:
990             case ACPI_ADR_SPACE_IPMI:
991             case ACPI_ADR_SPACE_GSBUS:
992 
993                 if ((UINT8) Op->Asl.Parent->Asl.Value.Integer !=
994                     AML_FIELD_ACCESS_BUFFER)
995                 {
996                     AslError (ASL_ERROR, ASL_MSG_REGION_BUFFER_ACCESS, Op, NULL);
997                 }
998                 break;
999 
1000             default:
1001 
1002                 /* Nothing to do for other address spaces */
1003 
1004                 break;
1005             }
1006         }
1007         else
1008         {
1009             /*
1010              * This is one element of the field list. Check to make sure
1011              * that it does not go beyond the end of the parent operation region.
1012              *
1013              * In the code below:
1014              *    Op->Asl.Parent->Asl.ExtraValue      - Region Length (bits)
1015              *    Op->Asl.ExtraValue                  - Field start offset (bits)
1016              *    Op->Asl.Child->Asl.Value.Integer32  - Field length (bits)
1017              *    Op->Asl.Child->Asl.ExtraValue       - Field access width (bits)
1018              */
1019             if (Op->Asl.Parent->Asl.ExtraValue && Op->Asl.Child)
1020             {
1021                 XfCheckFieldRange (Op,
1022                     Op->Asl.Parent->Asl.ExtraValue,
1023                     Op->Asl.ExtraValue,
1024                     (UINT32) Op->Asl.Child->Asl.Value.Integer,
1025                     Op->Asl.Child->Asl.ExtraValue);
1026             }
1027         }
1028     }
1029 
1030     /* 5) Check for a connection object */
1031 #if 0
1032     else if (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_CONNECTION)
1033     {
1034         return_ACPI_STATUS (Status);
1035     }
1036 #endif
1037 
1038     Op->Asl.Node = Node;
1039     return_ACPI_STATUS (Status);
1040 }
1041 
1042 
1043 /*******************************************************************************
1044  *
1045  * FUNCTION:    XfNamespaceLocateEnd
1046  *
1047  * PARAMETERS:  ASL_WALK_CALLBACK
1048  *
1049  * RETURN:      Status
1050  *
1051  * DESCRIPTION: Ascending callback used during cross reference. We only
1052  *              need to worry about scope management here.
1053  *
1054  ******************************************************************************/
1055 
1056 static ACPI_STATUS
1057 XfNamespaceLocateEnd (
1058     ACPI_PARSE_OBJECT       *Op,
1059     UINT32                  Level,
1060     void                    *Context)
1061 {
1062     ACPI_WALK_STATE         *WalkState = (ACPI_WALK_STATE *) Context;
1063     const ACPI_OPCODE_INFO  *OpInfo;
1064 
1065 
1066     ACPI_FUNCTION_TRACE (XfNamespaceLocateEnd);
1067 
1068 
1069     /* We are only interested in opcodes that have an associated name */
1070 
1071     OpInfo = AcpiPsGetOpcodeInfo (Op->Asl.AmlOpcode);
1072     if (!(OpInfo->Flags & AML_NAMED))
1073     {
1074         return_ACPI_STATUS (AE_OK);
1075     }
1076 
1077     /* Not interested in name references, we did not open a scope for them */
1078 
1079     if ((Op->Asl.ParseOpcode == PARSEOP_NAMESTRING) ||
1080         (Op->Asl.ParseOpcode == PARSEOP_NAMESEG)    ||
1081         (Op->Asl.ParseOpcode == PARSEOP_METHODCALL))
1082     {
1083         return_ACPI_STATUS (AE_OK);
1084     }
1085 
1086     /* Pop the scope stack if necessary */
1087 
1088     if (AcpiNsOpensScope (AslMapNamedOpcodeToDataType (Op->Asl.AmlOpcode)))
1089     {
1090 
1091         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
1092             "%s: Popping scope for Op %p\n",
1093             AcpiUtGetTypeName (OpInfo->ObjectType), Op));
1094 
1095         (void) AcpiDsScopeStackPop (WalkState);
1096     }
1097 
1098     return_ACPI_STATUS (AE_OK);
1099 }
1100 
1101 
1102 #ifdef __UNDER_DEVELOPMENT
1103 /*******************************************************************************
1104  *
1105  * FUNCTION:    XfIsObjectParental
1106  *
1107  * PARAMETERS:  ChildOp                 - Op to be checked
1108  *              PossibleParentOp        - Determine if this op is in the family
1109  *
1110  * RETURN:      TRUE if ChildOp is a descendent of PossibleParentOp
1111  *
1112  * DESCRIPTION: Determine if an Op is a descendent of another Op. Used to
1113  *              detect if a method is declared within another method.
1114  *
1115  ******************************************************************************/
1116 
1117 static BOOLEAN
1118 XfIsObjectParental (
1119     ACPI_PARSE_OBJECT       *ChildOp,
1120     ACPI_PARSE_OBJECT       *PossibleParentOp)
1121 {
1122     ACPI_PARSE_OBJECT       *ParentOp;
1123 
1124 
1125     /* Search upwards through the tree for possible parent */
1126 
1127     ParentOp = ChildOp;
1128     while (ParentOp)
1129     {
1130         if (ParentOp == PossibleParentOp)
1131         {
1132             return (TRUE);
1133         }
1134 
1135         ParentOp = ParentOp->Asl.Parent;
1136     }
1137 
1138     return (FALSE);
1139 }
1140 
1141 
1142 /*******************************************************************************
1143  *
1144  * FUNCTION:    XfGetParentMethod
1145  *
1146  * PARAMETERS:  Op                      - Op to be checked
1147  *
1148  * RETURN:      Op for parent method. NULL if object is not within a method.
1149  *
1150  * DESCRIPTION: Determine if an object is within a control method. Used to
1151  *              implement special rules for named references from within a
1152  *              control method.
1153  *
1154  * NOTE: It would be better to have the parser set a flag in the Op if possible.
1155  *
1156  ******************************************************************************/
1157 
1158 static ACPI_PARSE_OBJECT *
1159 XfGetParentMethod (
1160     ACPI_PARSE_OBJECT       *Op)
1161 {
1162     ACPI_PARSE_OBJECT       *ParentOp;
1163 
1164 
1165     if (!Op)
1166     {
1167         return (NULL);
1168     }
1169 
1170     if (Op->Asl.ParseOpcode == PARSEOP_METHOD)
1171     {
1172         return (NULL);
1173     }
1174 
1175     /* Walk upwards through the parse tree, up to the root if necessary */
1176 
1177     ParentOp = Op;
1178     while (ParentOp)
1179     {
1180         if (ParentOp->Asl.ParseOpcode == PARSEOP_METHOD)
1181         {
1182             return (ParentOp);
1183         }
1184 
1185         ParentOp = ParentOp->Asl.Parent;
1186     }
1187 
1188     /* Object is not within a method */
1189 
1190     return (NULL);
1191 }
1192 
1193 
1194 /*******************************************************************************
1195  *
1196  * FUNCTION:    XfCheckIllegalReference
1197  *
1198  * PARAMETERS:  Op                      - Op referring to the target
1199  *              TargetNode              - Target of the reference
1200  *
1201  * RETURN:      None. Emits error message for an illegal reference
1202  *
1203  * DESCRIPTION: Determine if a named reference is legal. A "named" reference
1204  *              is something like: Store(ABCD, ...), where ABCD is an AML
1205  *              Nameseg or Namepath.
1206  *
1207  * NOTE: Caller must ensure that the name Op is in fact a reference, and not
1208  *       an actual name declaration (creation of a named object).
1209  *
1210  ******************************************************************************/
1211 
1212 static void
1213 XfCheckIllegalReference (
1214     ACPI_PARSE_OBJECT       *Op,
1215     ACPI_NAMESPACE_NODE     *TargetNode)
1216 {
1217     ACPI_PARSE_OBJECT       *MethodOp1;
1218     ACPI_PARSE_OBJECT       *MethodOp2;
1219     ACPI_PARSE_OBJECT       *TargetOp;
1220 
1221 
1222     /*
1223      * Check for an illegal reference to a named object:
1224      *
1225      * 1) References from one control method to another, non-parent
1226      *    method are not allowed, they will fail at runtime.
1227      *
1228      * 2) Forward references within a control method are not allowed.
1229      *    AML interpreters use a one-pass parse of control methods
1230      *    so these forward references will fail at runtime.
1231      */
1232     TargetOp = TargetNode->Op;
1233 
1234     MethodOp1 = XfGetParentMethod (Op);
1235     MethodOp2 = XfGetParentMethod (TargetOp);
1236 
1237     /* Are both objects within control method(s)? */
1238 
1239     if (!MethodOp1 || !MethodOp2)
1240     {
1241         return;
1242     }
1243 
1244     /* Objects not in the same method? */
1245 
1246     if (MethodOp1 != MethodOp2)
1247     {
1248         /*
1249          * 1) Cross-method named reference
1250          *
1251          * This is OK if and only if the target reference is within in a
1252          * method that is a parent of current method
1253          */
1254         if (!XfIsObjectParental (MethodOp1, MethodOp2))
1255         {
1256             AslError (ASL_ERROR, ASL_MSG_ILLEGAL_METHOD_REF, Op,
1257                 Op->Asl.ExternalName);
1258         }
1259     }
1260 
1261     /*
1262      * 2) Both reference and target are in the same method. Check if this is
1263      * an (illegal) forward reference by examining the exact source code
1264      * location of each (the referenced object and the object declaration).
1265      * This is a bit nasty, yet effective.
1266      */
1267     else if (Op->Asl.LogicalByteOffset < TargetOp->Asl.LogicalByteOffset)
1268     {
1269         AslError (ASL_ERROR, ASL_MSG_ILLEGAL_FORWARD_REF, Op,
1270             Op->Asl.ExternalName);
1271     }
1272 
1273 }
1274 #endif
1275