xref: /titanic_50/usr/src/uts/intel/io/acpica/parser/psargs.c (revision 356f72340a69936724c69f2f87fffa6f5887f885)
1 /******************************************************************************
2  *
3  * Module Name: psargs - Parse AML opcode arguments
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 "acpi.h"
45 #include "accommon.h"
46 #include "acparser.h"
47 #include "amlcode.h"
48 #include "acnamesp.h"
49 #include "acdispat.h"
50 
51 #define _COMPONENT          ACPI_PARSER
52         ACPI_MODULE_NAME    ("psargs")
53 
54 /* Local prototypes */
55 
56 static UINT32
57 AcpiPsGetNextPackageLength (
58     ACPI_PARSE_STATE        *ParserState);
59 
60 static ACPI_PARSE_OBJECT *
61 AcpiPsGetNextField (
62     ACPI_PARSE_STATE        *ParserState);
63 
64 
65 /*******************************************************************************
66  *
67  * FUNCTION:    AcpiPsGetNextPackageLength
68  *
69  * PARAMETERS:  ParserState         - Current parser state object
70  *
71  * RETURN:      Decoded package length. On completion, the AML pointer points
72  *              past the length byte or bytes.
73  *
74  * DESCRIPTION: Decode and return a package length field.
75  *              Note: Largest package length is 28 bits, from ACPI specification
76  *
77  ******************************************************************************/
78 
79 static UINT32
80 AcpiPsGetNextPackageLength (
81     ACPI_PARSE_STATE        *ParserState)
82 {
83     UINT8                   *Aml = ParserState->Aml;
84     UINT32                  PackageLength = 0;
85     UINT32                  ByteCount;
86     UINT8                   ByteZeroMask = 0x3F; /* Default [0:5] */
87 
88 
89     ACPI_FUNCTION_TRACE (PsGetNextPackageLength);
90 
91 
92     /*
93      * Byte 0 bits [6:7] contain the number of additional bytes
94      * used to encode the package length, either 0,1,2, or 3
95      */
96     ByteCount = (Aml[0] >> 6);
97     ParserState->Aml += ((ACPI_SIZE) ByteCount + 1);
98 
99     /* Get bytes 3, 2, 1 as needed */
100 
101     while (ByteCount)
102     {
103         /*
104          * Final bit positions for the package length bytes:
105          *      Byte3->[20:27]
106          *      Byte2->[12:19]
107          *      Byte1->[04:11]
108          *      Byte0->[00:03]
109          */
110         PackageLength |= (Aml[ByteCount] << ((ByteCount << 3) - 4));
111 
112         ByteZeroMask = 0x0F; /* Use bits [0:3] of byte 0 */
113         ByteCount--;
114     }
115 
116     /* Byte 0 is a special case, either bits [0:3] or [0:5] are used */
117 
118     PackageLength |= (Aml[0] & ByteZeroMask);
119     return_UINT32 (PackageLength);
120 }
121 
122 
123 /*******************************************************************************
124  *
125  * FUNCTION:    AcpiPsGetNextPackageEnd
126  *
127  * PARAMETERS:  ParserState         - Current parser state object
128  *
129  * RETURN:      Pointer to end-of-package +1
130  *
131  * DESCRIPTION: Get next package length and return a pointer past the end of
132  *              the package. Consumes the package length field
133  *
134  ******************************************************************************/
135 
136 UINT8 *
137 AcpiPsGetNextPackageEnd (
138     ACPI_PARSE_STATE        *ParserState)
139 {
140     UINT8                   *Start = ParserState->Aml;
141     UINT32                  PackageLength;
142 
143 
144     ACPI_FUNCTION_TRACE (PsGetNextPackageEnd);
145 
146 
147     /* Function below updates ParserState->Aml */
148 
149     PackageLength = AcpiPsGetNextPackageLength (ParserState);
150 
151     return_PTR (Start + PackageLength); /* end of package */
152 }
153 
154 
155 /*******************************************************************************
156  *
157  * FUNCTION:    AcpiPsGetNextNamestring
158  *
159  * PARAMETERS:  ParserState         - Current parser state object
160  *
161  * RETURN:      Pointer to the start of the name string (pointer points into
162  *              the AML.
163  *
164  * DESCRIPTION: Get next raw namestring within the AML stream. Handles all name
165  *              prefix characters. Set parser state to point past the string.
166  *              (Name is consumed from the AML.)
167  *
168  ******************************************************************************/
169 
170 char *
171 AcpiPsGetNextNamestring (
172     ACPI_PARSE_STATE        *ParserState)
173 {
174     UINT8                   *Start = ParserState->Aml;
175     UINT8                   *End = ParserState->Aml;
176 
177 
178     ACPI_FUNCTION_TRACE (PsGetNextNamestring);
179 
180 
181     /* Point past any namestring prefix characters (backslash or carat) */
182 
183     while (ACPI_IS_ROOT_PREFIX (*End) ||
184            ACPI_IS_PARENT_PREFIX (*End))
185     {
186         End++;
187     }
188 
189     /* Decode the path prefix character */
190 
191     switch (*End)
192     {
193     case 0:
194 
195         /* NullName */
196 
197         if (End == Start)
198         {
199             Start = NULL;
200         }
201         End++;
202         break;
203 
204     case AML_DUAL_NAME_PREFIX:
205 
206         /* Two name segments */
207 
208         End += 1 + (2 * ACPI_NAME_SIZE);
209         break;
210 
211     case AML_MULTI_NAME_PREFIX_OP:
212 
213         /* Multiple name segments, 4 chars each, count in next byte */
214 
215         End += 2 + (*(End + 1) * ACPI_NAME_SIZE);
216         break;
217 
218     default:
219 
220         /* Single name segment */
221 
222         End += ACPI_NAME_SIZE;
223         break;
224     }
225 
226     ParserState->Aml = End;
227     return_PTR ((char *) Start);
228 }
229 
230 
231 /*******************************************************************************
232  *
233  * FUNCTION:    AcpiPsGetNextNamepath
234  *
235  * PARAMETERS:  ParserState         - Current parser state object
236  *              Arg                 - Where the namepath will be stored
237  *              ArgCount            - If the namepath points to a control method
238  *                                    the method's argument is returned here.
239  *              PossibleMethodCall  - Whether the namepath can possibly be the
240  *                                    start of a method call
241  *
242  * RETURN:      Status
243  *
244  * DESCRIPTION: Get next name (if method call, return # of required args).
245  *              Names are looked up in the internal namespace to determine
246  *              if the name represents a control method. If a method
247  *              is found, the number of arguments to the method is returned.
248  *              This information is critical for parsing to continue correctly.
249  *
250  ******************************************************************************/
251 
252 ACPI_STATUS
253 AcpiPsGetNextNamepath (
254     ACPI_WALK_STATE         *WalkState,
255     ACPI_PARSE_STATE        *ParserState,
256     ACPI_PARSE_OBJECT       *Arg,
257     BOOLEAN                 PossibleMethodCall)
258 {
259     ACPI_STATUS             Status;
260     char                    *Path;
261     ACPI_PARSE_OBJECT       *NameOp;
262     ACPI_OPERAND_OBJECT     *MethodDesc;
263     ACPI_NAMESPACE_NODE     *Node;
264     UINT8                   *Start = ParserState->Aml;
265 
266 
267     ACPI_FUNCTION_TRACE (PsGetNextNamepath);
268 
269 
270     Path = AcpiPsGetNextNamestring (ParserState);
271     AcpiPsInitOp (Arg, AML_INT_NAMEPATH_OP);
272 
273     /* Null path case is allowed, just exit */
274 
275     if (!Path)
276     {
277         Arg->Common.Value.Name = Path;
278         return_ACPI_STATUS (AE_OK);
279     }
280 
281     /*
282      * Lookup the name in the internal namespace, starting with the current
283      * scope. We don't want to add anything new to the namespace here,
284      * however, so we use MODE_EXECUTE.
285      * Allow searching of the parent tree, but don't open a new scope -
286      * we just want to lookup the object (must be mode EXECUTE to perform
287      * the upsearch)
288      */
289     Status = AcpiNsLookup (WalkState->ScopeInfo, Path,
290         ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
291         ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE, NULL, &Node);
292 
293     /*
294      * If this name is a control method invocation, we must
295      * setup the method call
296      */
297     if (ACPI_SUCCESS (Status) &&
298         PossibleMethodCall &&
299         (Node->Type == ACPI_TYPE_METHOD))
300     {
301         if (WalkState->Opcode == AML_UNLOAD_OP)
302         {
303             /*
304              * AcpiPsGetNextNamestring has increased the AML pointer,
305              * so we need to restore the saved AML pointer for method call.
306              */
307             WalkState->ParserState.Aml = Start;
308             WalkState->ArgCount = 1;
309             AcpiPsInitOp (Arg, AML_INT_METHODCALL_OP);
310             return_ACPI_STATUS (AE_OK);
311         }
312 
313         /* This name is actually a control method invocation */
314 
315         MethodDesc = AcpiNsGetAttachedObject (Node);
316         ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
317             "Control Method - %p Desc %p Path=%p\n", Node, MethodDesc, Path));
318 
319         NameOp = AcpiPsAllocOp (AML_INT_NAMEPATH_OP, Start);
320         if (!NameOp)
321         {
322             return_ACPI_STATUS (AE_NO_MEMORY);
323         }
324 
325         /* Change Arg into a METHOD CALL and attach name to it */
326 
327         AcpiPsInitOp (Arg, AML_INT_METHODCALL_OP);
328         NameOp->Common.Value.Name = Path;
329 
330         /* Point METHODCALL/NAME to the METHOD Node */
331 
332         NameOp->Common.Node = Node;
333         AcpiPsAppendArg (Arg, NameOp);
334 
335         if (!MethodDesc)
336         {
337             ACPI_ERROR ((AE_INFO,
338                 "Control Method %p has no attached object",
339                 Node));
340             return_ACPI_STATUS (AE_AML_INTERNAL);
341         }
342 
343         ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
344             "Control Method - %p Args %X\n",
345             Node, MethodDesc->Method.ParamCount));
346 
347         /* Get the number of arguments to expect */
348 
349         WalkState->ArgCount = MethodDesc->Method.ParamCount;
350         return_ACPI_STATUS (AE_OK);
351     }
352 
353     /*
354      * Special handling if the name was not found during the lookup -
355      * some NotFound cases are allowed
356      */
357     if (Status == AE_NOT_FOUND)
358     {
359         /* 1) NotFound is ok during load pass 1/2 (allow forward references) */
360 
361         if ((WalkState->ParseFlags & ACPI_PARSE_MODE_MASK) !=
362             ACPI_PARSE_EXECUTE)
363         {
364             Status = AE_OK;
365         }
366 
367         /* 2) NotFound during a CondRefOf(x) is ok by definition */
368 
369         else if (WalkState->Op->Common.AmlOpcode == AML_COND_REF_OF_OP)
370         {
371             Status = AE_OK;
372         }
373 
374         /*
375          * 3) NotFound while building a Package is ok at this point, we
376          * may flag as an error later if slack mode is not enabled.
377          * (Some ASL code depends on allowing this behavior)
378          */
379         else if ((Arg->Common.Parent) &&
380             ((Arg->Common.Parent->Common.AmlOpcode == AML_PACKAGE_OP) ||
381              (Arg->Common.Parent->Common.AmlOpcode == AML_VAR_PACKAGE_OP)))
382         {
383             Status = AE_OK;
384         }
385     }
386 
387     /* Final exception check (may have been changed from code above) */
388 
389     if (ACPI_FAILURE (Status))
390     {
391         ACPI_ERROR_NAMESPACE (Path, Status);
392 
393         if ((WalkState->ParseFlags & ACPI_PARSE_MODE_MASK) ==
394             ACPI_PARSE_EXECUTE)
395         {
396             /* Report a control method execution error */
397 
398             Status = AcpiDsMethodError (Status, WalkState);
399         }
400     }
401 
402     /* Save the namepath */
403 
404     Arg->Common.Value.Name = Path;
405     return_ACPI_STATUS (Status);
406 }
407 
408 
409 /*******************************************************************************
410  *
411  * FUNCTION:    AcpiPsGetNextSimpleArg
412  *
413  * PARAMETERS:  ParserState         - Current parser state object
414  *              ArgType             - The argument type (AML_*_ARG)
415  *              Arg                 - Where the argument is returned
416  *
417  * RETURN:      None
418  *
419  * DESCRIPTION: Get the next simple argument (constant, string, or namestring)
420  *
421  ******************************************************************************/
422 
423 void
424 AcpiPsGetNextSimpleArg (
425     ACPI_PARSE_STATE        *ParserState,
426     UINT32                  ArgType,
427     ACPI_PARSE_OBJECT       *Arg)
428 {
429     UINT32                  Length;
430     UINT16                  Opcode;
431     UINT8                   *Aml = ParserState->Aml;
432 
433 
434     ACPI_FUNCTION_TRACE_U32 (PsGetNextSimpleArg, ArgType);
435 
436 
437     switch (ArgType)
438     {
439     case ARGP_BYTEDATA:
440 
441         /* Get 1 byte from the AML stream */
442 
443         Opcode = AML_BYTE_OP;
444         Arg->Common.Value.Integer = (UINT64) *Aml;
445         Length = 1;
446         break;
447 
448     case ARGP_WORDDATA:
449 
450         /* Get 2 bytes from the AML stream */
451 
452         Opcode = AML_WORD_OP;
453         ACPI_MOVE_16_TO_64 (&Arg->Common.Value.Integer, Aml);
454         Length = 2;
455         break;
456 
457     case ARGP_DWORDDATA:
458 
459         /* Get 4 bytes from the AML stream */
460 
461         Opcode = AML_DWORD_OP;
462         ACPI_MOVE_32_TO_64 (&Arg->Common.Value.Integer, Aml);
463         Length = 4;
464         break;
465 
466     case ARGP_QWORDDATA:
467 
468         /* Get 8 bytes from the AML stream */
469 
470         Opcode = AML_QWORD_OP;
471         ACPI_MOVE_64_TO_64 (&Arg->Common.Value.Integer, Aml);
472         Length = 8;
473         break;
474 
475     case ARGP_CHARLIST:
476 
477         /* Get a pointer to the string, point past the string */
478 
479         Opcode = AML_STRING_OP;
480         Arg->Common.Value.String = ACPI_CAST_PTR (char, Aml);
481 
482         /* Find the null terminator */
483 
484         Length = 0;
485         while (Aml[Length])
486         {
487             Length++;
488         }
489         Length++;
490         break;
491 
492     case ARGP_NAME:
493     case ARGP_NAMESTRING:
494 
495         AcpiPsInitOp (Arg, AML_INT_NAMEPATH_OP);
496         Arg->Common.Value.Name = AcpiPsGetNextNamestring (ParserState);
497         return_VOID;
498 
499     default:
500 
501         ACPI_ERROR ((AE_INFO, "Invalid ArgType 0x%X", ArgType));
502         return_VOID;
503     }
504 
505     AcpiPsInitOp (Arg, Opcode);
506     ParserState->Aml += Length;
507     return_VOID;
508 }
509 
510 
511 /*******************************************************************************
512  *
513  * FUNCTION:    AcpiPsGetNextField
514  *
515  * PARAMETERS:  ParserState         - Current parser state object
516  *
517  * RETURN:      A newly allocated FIELD op
518  *
519  * DESCRIPTION: Get next field (NamedField, ReservedField, or AccessField)
520  *
521  ******************************************************************************/
522 
523 static ACPI_PARSE_OBJECT *
524 AcpiPsGetNextField (
525     ACPI_PARSE_STATE        *ParserState)
526 {
527     UINT8                   *Aml;
528     ACPI_PARSE_OBJECT       *Field;
529     ACPI_PARSE_OBJECT       *Arg = NULL;
530     UINT16                  Opcode;
531     UINT32                  Name;
532     UINT8                   AccessType;
533     UINT8                   AccessAttribute;
534     UINT8                   AccessLength;
535     UINT32                  PkgLength;
536     UINT8                   *PkgEnd;
537     UINT32                  BufferLength;
538 
539 
540     ACPI_FUNCTION_TRACE (PsGetNextField);
541 
542 
543     Aml = ParserState->Aml;
544 
545     /* Determine field type */
546 
547     switch (ACPI_GET8 (ParserState->Aml))
548     {
549     case AML_FIELD_OFFSET_OP:
550 
551         Opcode = AML_INT_RESERVEDFIELD_OP;
552         ParserState->Aml++;
553         break;
554 
555     case AML_FIELD_ACCESS_OP:
556 
557         Opcode = AML_INT_ACCESSFIELD_OP;
558         ParserState->Aml++;
559         break;
560 
561     case AML_FIELD_CONNECTION_OP:
562 
563         Opcode = AML_INT_CONNECTION_OP;
564         ParserState->Aml++;
565         break;
566 
567     case AML_FIELD_EXT_ACCESS_OP:
568 
569         Opcode = AML_INT_EXTACCESSFIELD_OP;
570         ParserState->Aml++;
571         break;
572 
573     default:
574 
575         Opcode = AML_INT_NAMEDFIELD_OP;
576         break;
577     }
578 
579     /* Allocate a new field op */
580 
581     Field = AcpiPsAllocOp (Opcode, Aml);
582     if (!Field)
583     {
584         return_PTR (NULL);
585     }
586 
587     /* Decode the field type */
588 
589     switch (Opcode)
590     {
591     case AML_INT_NAMEDFIELD_OP:
592 
593         /* Get the 4-character name */
594 
595         ACPI_MOVE_32_TO_32 (&Name, ParserState->Aml);
596         AcpiPsSetName (Field, Name);
597         ParserState->Aml += ACPI_NAME_SIZE;
598 
599         /* Get the length which is encoded as a package length */
600 
601         Field->Common.Value.Size = AcpiPsGetNextPackageLength (ParserState);
602         break;
603 
604 
605     case AML_INT_RESERVEDFIELD_OP:
606 
607         /* Get the length which is encoded as a package length */
608 
609         Field->Common.Value.Size = AcpiPsGetNextPackageLength (ParserState);
610         break;
611 
612 
613     case AML_INT_ACCESSFIELD_OP:
614     case AML_INT_EXTACCESSFIELD_OP:
615 
616         /*
617          * Get AccessType and AccessAttrib and merge into the field Op
618          * AccessType is first operand, AccessAttribute is second. stuff
619          * these bytes into the node integer value for convenience.
620          */
621 
622         /* Get the two bytes (Type/Attribute) */
623 
624         AccessType = ACPI_GET8 (ParserState->Aml);
625         ParserState->Aml++;
626         AccessAttribute = ACPI_GET8 (ParserState->Aml);
627         ParserState->Aml++;
628 
629         Field->Common.Value.Integer = (UINT8) AccessType;
630         Field->Common.Value.Integer |= (UINT16) (AccessAttribute << 8);
631 
632         /* This opcode has a third byte, AccessLength */
633 
634         if (Opcode == AML_INT_EXTACCESSFIELD_OP)
635         {
636             AccessLength = ACPI_GET8 (ParserState->Aml);
637             ParserState->Aml++;
638 
639             Field->Common.Value.Integer |= (UINT32) (AccessLength << 16);
640         }
641         break;
642 
643 
644     case AML_INT_CONNECTION_OP:
645 
646         /*
647          * Argument for Connection operator can be either a Buffer
648          * (resource descriptor), or a NameString.
649          */
650         Aml = ParserState->Aml;
651         if (ACPI_GET8 (ParserState->Aml) == AML_BUFFER_OP)
652         {
653             ParserState->Aml++;
654 
655             PkgEnd = ParserState->Aml;
656             PkgLength = AcpiPsGetNextPackageLength (ParserState);
657             PkgEnd += PkgLength;
658 
659             if (ParserState->Aml < PkgEnd)
660             {
661                 /* Non-empty list */
662 
663                 Arg = AcpiPsAllocOp (AML_INT_BYTELIST_OP, Aml);
664                 if (!Arg)
665                 {
666                     AcpiPsFreeOp (Field);
667                     return_PTR (NULL);
668                 }
669 
670                 /* Get the actual buffer length argument */
671 
672                 Opcode = ACPI_GET8 (ParserState->Aml);
673                 ParserState->Aml++;
674 
675                 switch (Opcode)
676                 {
677                 case AML_BYTE_OP:       /* AML_BYTEDATA_ARG */
678 
679                     BufferLength = ACPI_GET8 (ParserState->Aml);
680                     ParserState->Aml += 1;
681                     break;
682 
683                 case AML_WORD_OP:       /* AML_WORDDATA_ARG */
684 
685                     BufferLength = ACPI_GET16 (ParserState->Aml);
686                     ParserState->Aml += 2;
687                     break;
688 
689                 case AML_DWORD_OP:      /* AML_DWORDATA_ARG */
690 
691                     BufferLength = ACPI_GET32 (ParserState->Aml);
692                     ParserState->Aml += 4;
693                     break;
694 
695                 default:
696 
697                     BufferLength = 0;
698                     break;
699                 }
700 
701                 /* Fill in bytelist data */
702 
703                 Arg->Named.Value.Size = BufferLength;
704                 Arg->Named.Data = ParserState->Aml;
705             }
706 
707             /* Skip to End of byte data */
708 
709             ParserState->Aml = PkgEnd;
710         }
711         else
712         {
713             Arg = AcpiPsAllocOp (AML_INT_NAMEPATH_OP, Aml);
714             if (!Arg)
715             {
716                 AcpiPsFreeOp (Field);
717                 return_PTR (NULL);
718             }
719 
720             /* Get the Namestring argument */
721 
722             Arg->Common.Value.Name = AcpiPsGetNextNamestring (ParserState);
723         }
724 
725         /* Link the buffer/namestring to parent (CONNECTION_OP) */
726 
727         AcpiPsAppendArg (Field, Arg);
728         break;
729 
730 
731     default:
732 
733         /* Opcode was set in previous switch */
734         break;
735     }
736 
737     return_PTR (Field);
738 }
739 
740 
741 /*******************************************************************************
742  *
743  * FUNCTION:    AcpiPsGetNextArg
744  *
745  * PARAMETERS:  WalkState           - Current state
746  *              ParserState         - Current parser state object
747  *              ArgType             - The argument type (AML_*_ARG)
748  *              ReturnArg           - Where the next arg is returned
749  *
750  * RETURN:      Status, and an op object containing the next argument.
751  *
752  * DESCRIPTION: Get next argument (including complex list arguments that require
753  *              pushing the parser stack)
754  *
755  ******************************************************************************/
756 
757 ACPI_STATUS
758 AcpiPsGetNextArg (
759     ACPI_WALK_STATE         *WalkState,
760     ACPI_PARSE_STATE        *ParserState,
761     UINT32                  ArgType,
762     ACPI_PARSE_OBJECT       **ReturnArg)
763 {
764     ACPI_PARSE_OBJECT       *Arg = NULL;
765     ACPI_PARSE_OBJECT       *Prev = NULL;
766     ACPI_PARSE_OBJECT       *Field;
767     UINT32                  Subop;
768     ACPI_STATUS             Status = AE_OK;
769 
770 
771     ACPI_FUNCTION_TRACE_PTR (PsGetNextArg, ParserState);
772 
773 
774     switch (ArgType)
775     {
776     case ARGP_BYTEDATA:
777     case ARGP_WORDDATA:
778     case ARGP_DWORDDATA:
779     case ARGP_CHARLIST:
780     case ARGP_NAME:
781     case ARGP_NAMESTRING:
782 
783         /* Constants, strings, and namestrings are all the same size */
784 
785         Arg = AcpiPsAllocOp (AML_BYTE_OP, ParserState->Aml);
786         if (!Arg)
787         {
788             return_ACPI_STATUS (AE_NO_MEMORY);
789         }
790 
791         AcpiPsGetNextSimpleArg (ParserState, ArgType, Arg);
792         break;
793 
794     case ARGP_PKGLENGTH:
795 
796         /* Package length, nothing returned */
797 
798         ParserState->PkgEnd = AcpiPsGetNextPackageEnd (ParserState);
799         break;
800 
801     case ARGP_FIELDLIST:
802 
803         if (ParserState->Aml < ParserState->PkgEnd)
804         {
805             /* Non-empty list */
806 
807             while (ParserState->Aml < ParserState->PkgEnd)
808             {
809                 Field = AcpiPsGetNextField (ParserState);
810                 if (!Field)
811                 {
812                     return_ACPI_STATUS (AE_NO_MEMORY);
813                 }
814 
815                 if (Prev)
816                 {
817                     Prev->Common.Next = Field;
818                 }
819                 else
820                 {
821                     Arg = Field;
822                 }
823                 Prev = Field;
824             }
825 
826             /* Skip to End of byte data */
827 
828             ParserState->Aml = ParserState->PkgEnd;
829         }
830         break;
831 
832     case ARGP_BYTELIST:
833 
834         if (ParserState->Aml < ParserState->PkgEnd)
835         {
836             /* Non-empty list */
837 
838             Arg = AcpiPsAllocOp (AML_INT_BYTELIST_OP,
839                 ParserState->Aml);
840             if (!Arg)
841             {
842                 return_ACPI_STATUS (AE_NO_MEMORY);
843             }
844 
845             /* Fill in bytelist data */
846 
847             Arg->Common.Value.Size = (UINT32)
848                 ACPI_PTR_DIFF (ParserState->PkgEnd, ParserState->Aml);
849             Arg->Named.Data = ParserState->Aml;
850 
851             /* Skip to End of byte data */
852 
853             ParserState->Aml = ParserState->PkgEnd;
854         }
855         break;
856 
857     case ARGP_TARGET:
858     case ARGP_SUPERNAME:
859     case ARGP_SIMPLENAME:
860     case ARGP_NAME_OR_REF:
861 
862         Subop = AcpiPsPeekOpcode (ParserState);
863         if (Subop == 0                  ||
864             AcpiPsIsLeadingChar (Subop) ||
865             ACPI_IS_ROOT_PREFIX (Subop) ||
866             ACPI_IS_PARENT_PREFIX (Subop))
867         {
868             /* NullName or NameString */
869 
870             Arg = AcpiPsAllocOp (AML_INT_NAMEPATH_OP, ParserState->Aml);
871             if (!Arg)
872             {
873                 return_ACPI_STATUS (AE_NO_MEMORY);
874             }
875 
876             /* To support SuperName arg of Unload */
877 
878             if (WalkState->Opcode == AML_UNLOAD_OP)
879             {
880                 Status = AcpiPsGetNextNamepath (WalkState, ParserState,
881                     Arg, ACPI_POSSIBLE_METHOD_CALL);
882 
883                 /*
884                  * If the SuperName argument is a method call, we have
885                  * already restored the AML pointer, just free this Arg
886                  */
887                 if (Arg->Common.AmlOpcode == AML_INT_METHODCALL_OP)
888                 {
889                     AcpiPsFreeOp (Arg);
890                     Arg = NULL;
891                 }
892             }
893             else
894             {
895                 Status = AcpiPsGetNextNamepath (WalkState, ParserState,
896                     Arg, ACPI_NOT_METHOD_CALL);
897             }
898         }
899         else
900         {
901             /* Single complex argument, nothing returned */
902 
903             WalkState->ArgCount = 1;
904         }
905         break;
906 
907     case ARGP_DATAOBJ:
908     case ARGP_TERMARG:
909 
910         /* Single complex argument, nothing returned */
911 
912         WalkState->ArgCount = 1;
913         break;
914 
915     case ARGP_DATAOBJLIST:
916     case ARGP_TERMLIST:
917     case ARGP_OBJLIST:
918 
919         if (ParserState->Aml < ParserState->PkgEnd)
920         {
921             /* Non-empty list of variable arguments, nothing returned */
922 
923             WalkState->ArgCount = ACPI_VAR_ARGS;
924         }
925         break;
926 
927     default:
928 
929         ACPI_ERROR ((AE_INFO, "Invalid ArgType: 0x%X", ArgType));
930         Status = AE_AML_OPERAND_TYPE;
931         break;
932     }
933 
934     *ReturnArg = Arg;
935     return_ACPI_STATUS (Status);
936 }
937