1 /******************************************************************************
2  *
3  * Module Name: dsfield - Dispatcher field routines
4  *              $Revision: 78 $
5  *
6  *****************************************************************************/
7 
8 /******************************************************************************
9  *
10  * 1. Copyright Notice
11  *
12  * Some or all of this work - Copyright (c) 1999 - 2005, Intel Corp.
13  * All rights reserved.
14  *
15  * 2. License
16  *
17  * 2.1. This is your license from Intel Corp. under its intellectual property
18  * rights.  You may have additional license terms from the party that provided
19  * you this software, covering your right to use that party's intellectual
20  * property rights.
21  *
22  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
23  * copy of the source code appearing in this file ("Covered Code") an
24  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
25  * base code distributed originally by Intel ("Original Intel Code") to copy,
26  * make derivatives, distribute, use and display any portion of the Covered
27  * Code in any form, with the right to sublicense such rights; and
28  *
29  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
30  * license (with the right to sublicense), under only those claims of Intel
31  * patents that are infringed by the Original Intel Code, to make, use, sell,
32  * offer to sell, and import the Covered Code and derivative works thereof
33  * solely to the minimum extent necessary to exercise the above copyright
34  * license, and in no event shall the patent license extend to any additions
35  * to or modifications of the Original Intel Code.  No other license or right
36  * is granted directly or by implication, estoppel or otherwise;
37  *
38  * The above copyright and patent license is granted only if the following
39  * conditions are met:
40  *
41  * 3. Conditions
42  *
43  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
44  * Redistribution of source code of any substantial portion of the Covered
45  * Code or modification with rights to further distribute source must include
46  * the above Copyright Notice, the above License, this list of Conditions,
47  * and the following Disclaimer and Export Compliance provision.  In addition,
48  * Licensee must cause all Covered Code to which Licensee contributes to
49  * contain a file documenting the changes Licensee made to create that Covered
50  * Code and the date of any change.  Licensee must include in that file the
51  * documentation of any changes made by any predecessor Licensee.  Licensee
52  * must include a prominent statement that the modification is derived,
53  * directly or indirectly, from Original Intel Code.
54  *
55  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
56  * Redistribution of source code of any substantial portion of the Covered
57  * Code or modification without rights to further distribute source must
58  * include the following Disclaimer and Export Compliance provision in the
59  * documentation and/or other materials provided with distribution.  In
60  * addition, Licensee may not authorize further sublicense of source of any
61  * portion of the Covered Code, and must include terms to the effect that the
62  * license from Licensee to its licensee is limited to the intellectual
63  * property embodied in the software Licensee provides to its licensee, and
64  * not to intellectual property embodied in modifications its licensee may
65  * make.
66  *
67  * 3.3. Redistribution of Executable. Redistribution in executable form of any
68  * substantial portion of the Covered Code or modification must reproduce the
69  * above Copyright Notice, and the following Disclaimer and Export Compliance
70  * provision in the documentation and/or other materials provided with the
71  * distribution.
72  *
73  * 3.4. Intel retains all right, title, and interest in and to the Original
74  * Intel Code.
75  *
76  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
77  * Intel shall be used in advertising or otherwise to promote the sale, use or
78  * other dealings in products derived from or relating to the Covered Code
79  * without prior written authorization from Intel.
80  *
81  * 4. Disclaimer and Export Compliance
82  *
83  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
84  * HERE.  ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
85  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT,  ASSISTANCE,
86  * INSTALLATION, TRAINING OR OTHER SERVICES.  INTEL WILL NOT PROVIDE ANY
87  * UPDATES, ENHANCEMENTS OR EXTENSIONS.  INTEL SPECIFICALLY DISCLAIMS ANY
88  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
89  * PARTICULAR PURPOSE.
90  *
91  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
92  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
93  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
94  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
95  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
96  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.  THESE LIMITATIONS
97  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
98  * LIMITED REMEDY.
99  *
100  * 4.3. Licensee shall not export, either directly or indirectly, any of this
101  * software or system incorporating such software without first obtaining any
102  * required license or other approval from the U. S. Department of Commerce or
103  * any other agency or department of the United States Government.  In the
104  * event Licensee exports any such software from the United States or
105  * re-exports any such software from a foreign destination, Licensee shall
106  * ensure that the distribution and export/re-export of the software is in
107  * compliance with all laws, regulations, orders, or other restrictions of the
108  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
109  * any of its subsidiaries will export/re-export any technical data, process,
110  * software, or service, directly or indirectly, to any country for which the
111  * United States government or any agency thereof requires an export license,
112  * other governmental approval, or letter of assurance, without first obtaining
113  * such license, approval or letter.
114  *
115  *****************************************************************************/
116 
117 #define __DSFIELD_C__
118 
119 #include "acpi.h"
120 #include "amlcode.h"
121 #include "acdispat.h"
122 #include "acinterp.h"
123 #include "acnamesp.h"
124 #include "acparser.h"
125 
126 
127 #define _COMPONENT          ACPI_DISPATCHER
128         ACPI_MODULE_NAME    ("dsfield")
129 
130 /* Local prototypes */
131 
132 static ACPI_STATUS
133 AcpiDsGetFieldNames (
134     ACPI_CREATE_FIELD_INFO  *Info,
135     ACPI_WALK_STATE         *WalkState,
136     ACPI_PARSE_OBJECT       *Arg);
137 
138 
139 /*******************************************************************************
140  *
141  * FUNCTION:    AcpiDsCreateBufferField
142  *
143  * PARAMETERS:  Op                  - Current parse op (CreateXXField)
144  *              WalkState           - Current state
145  *
146  * RETURN:      Status
147  *
148  * DESCRIPTION: Execute the CreateField operators:
149  *              CreateBitFieldOp,
150  *              CreateByteFieldOp,
151  *              CreateWordFieldOp,
152  *              CreateDWordFieldOp,
153  *              CreateQWordFieldOp,
154  *              CreateFieldOp       (all of which define a field in a buffer)
155  *
156  ******************************************************************************/
157 
158 ACPI_STATUS
159 AcpiDsCreateBufferField (
160     ACPI_PARSE_OBJECT       *Op,
161     ACPI_WALK_STATE         *WalkState)
162 {
163     ACPI_PARSE_OBJECT       *Arg;
164     ACPI_NAMESPACE_NODE     *Node;
165     ACPI_STATUS             Status;
166     ACPI_OPERAND_OBJECT     *ObjDesc;
167     ACPI_OPERAND_OBJECT     *SecondDesc = NULL;
168     UINT32                  Flags;
169 
170 
171     ACPI_FUNCTION_TRACE ("DsCreateBufferField");
172 
173 
174     /* Get the NameString argument */
175 
176     if (Op->Common.AmlOpcode == AML_CREATE_FIELD_OP)
177     {
178         Arg = AcpiPsGetArg (Op, 3);
179     }
180     else
181     {
182         /* Create Bit/Byte/Word/Dword field */
183 
184         Arg = AcpiPsGetArg (Op, 2);
185     }
186 
187     if (!Arg)
188     {
189         return_ACPI_STATUS (AE_AML_NO_OPERAND);
190     }
191 
192     if (WalkState->DeferredNode)
193     {
194         Node = WalkState->DeferredNode;
195         Status = AE_OK;
196     }
197     else
198     {
199         /*
200          * During the load phase, we want to enter the name of the field into
201          * the namespace.  During the execute phase (when we evaluate the size
202          * operand), we want to lookup the name
203          */
204         if (WalkState->ParseFlags & ACPI_PARSE_EXECUTE)
205         {
206             Flags = ACPI_NS_NO_UPSEARCH | ACPI_NS_DONT_OPEN_SCOPE;
207         }
208         else
209         {
210             Flags = ACPI_NS_NO_UPSEARCH | ACPI_NS_DONT_OPEN_SCOPE |
211                     ACPI_NS_ERROR_IF_FOUND;
212         }
213 
214         /*
215          * Enter the NameString into the namespace
216          */
217         Status = AcpiNsLookup (WalkState->ScopeInfo, Arg->Common.Value.String,
218                                 ACPI_TYPE_ANY, ACPI_IMODE_LOAD_PASS1,
219                                 Flags, WalkState, &(Node));
220         if (ACPI_FAILURE (Status))
221         {
222             ACPI_REPORT_NSERROR (Arg->Common.Value.String, Status);
223             return_ACPI_STATUS (Status);
224         }
225     }
226 
227     /* We could put the returned object (Node) on the object stack for later,
228      * but for now, we will put it in the "op" object that the parser uses,
229      * so we can get it again at the end of this scope
230      */
231     Op->Common.Node = Node;
232 
233     /*
234      * If there is no object attached to the node, this node was just created
235      * and we need to create the field object.  Otherwise, this was a lookup
236      * of an existing node and we don't want to create the field object again.
237      */
238     ObjDesc = AcpiNsGetAttachedObject (Node);
239     if (ObjDesc)
240     {
241         return_ACPI_STATUS (AE_OK);
242     }
243 
244     /*
245      * The Field definition is not fully parsed at this time.
246      * (We must save the address of the AML for the buffer and index operands)
247      */
248 
249     /* Create the buffer field object */
250 
251     ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_BUFFER_FIELD);
252     if (!ObjDesc)
253     {
254         Status = AE_NO_MEMORY;
255         goto Cleanup;
256     }
257 
258     /*
259      * Remember location in AML stream of the field unit
260      * opcode and operands -- since the buffer and index
261      * operands must be evaluated.
262      */
263     SecondDesc                  = ObjDesc->Common.NextObject;
264     SecondDesc->Extra.AmlStart  = Op->Named.Data;
265     SecondDesc->Extra.AmlLength = Op->Named.Length;
266     ObjDesc->BufferField.Node   = Node;
267 
268     /* Attach constructed field descriptors to parent node */
269 
270     Status = AcpiNsAttachObject (Node, ObjDesc, ACPI_TYPE_BUFFER_FIELD);
271     if (ACPI_FAILURE (Status))
272     {
273         goto Cleanup;
274     }
275 
276 
277 Cleanup:
278 
279     /* Remove local reference to the object */
280 
281     AcpiUtRemoveReference (ObjDesc);
282     return_ACPI_STATUS (Status);
283 }
284 
285 
286 /*******************************************************************************
287  *
288  * FUNCTION:    AcpiDsGetFieldNames
289  *
290  * PARAMETERS:  Info            - CreateField info structure
291  *  `           WalkState       - Current method state
292  *              Arg             - First parser arg for the field name list
293  *
294  * RETURN:      Status
295  *
296  * DESCRIPTION: Process all named fields in a field declaration.  Names are
297  *              entered into the namespace.
298  *
299  ******************************************************************************/
300 
301 static ACPI_STATUS
302 AcpiDsGetFieldNames (
303     ACPI_CREATE_FIELD_INFO  *Info,
304     ACPI_WALK_STATE         *WalkState,
305     ACPI_PARSE_OBJECT       *Arg)
306 {
307     ACPI_STATUS             Status;
308     ACPI_INTEGER            Position;
309 
310 
311     ACPI_FUNCTION_TRACE_PTR ("DsGetFieldNames", Info);
312 
313 
314     /* First field starts at bit zero */
315 
316     Info->FieldBitPosition = 0;
317 
318     /* Process all elements in the field list (of parse nodes) */
319 
320     while (Arg)
321     {
322         /*
323          * Three types of field elements are handled:
324          * 1) Offset - specifies a bit offset
325          * 2) AccessAs - changes the access mode
326          * 3) Name - Enters a new named field into the namespace
327          */
328         switch (Arg->Common.AmlOpcode)
329         {
330         case AML_INT_RESERVEDFIELD_OP:
331 
332             Position = (ACPI_INTEGER) Info->FieldBitPosition
333                         + (ACPI_INTEGER) Arg->Common.Value.Size;
334 
335             if (Position > ACPI_UINT32_MAX)
336             {
337                 ACPI_REPORT_ERROR ((
338                     "Bit offset within field too large (> 0xFFFFFFFF)\n"));
339                 return_ACPI_STATUS (AE_SUPPORT);
340             }
341 
342             Info->FieldBitPosition = (UINT32) Position;
343             break;
344 
345 
346         case AML_INT_ACCESSFIELD_OP:
347 
348             /*
349              * Get a new AccessType and AccessAttribute -- to be used for all
350              * field units that follow, until field end or another AccessAs
351              * keyword.
352              *
353              * In FieldFlags, preserve the flag bits other than the
354              * ACCESS_TYPE bits
355              */
356             Info->FieldFlags = (UINT8)
357                 ((Info->FieldFlags & ~(AML_FIELD_ACCESS_TYPE_MASK)) |
358                 ((UINT8) ((UINT32) Arg->Common.Value.Integer >> 8)));
359 
360             Info->Attribute = (UINT8) (Arg->Common.Value.Integer);
361             break;
362 
363 
364         case AML_INT_NAMEDFIELD_OP:
365 
366             /* Lookup the name */
367 
368             Status = AcpiNsLookup (WalkState->ScopeInfo,
369                             (char *) &Arg->Named.Name,
370                             Info->FieldType, ACPI_IMODE_EXECUTE,
371                             ACPI_NS_DONT_OPEN_SCOPE,
372                             WalkState, &Info->FieldNode);
373             if (ACPI_FAILURE (Status))
374             {
375                 ACPI_REPORT_NSERROR ((char *) &Arg->Named.Name, Status);
376                 if (Status != AE_ALREADY_EXISTS)
377                 {
378                     return_ACPI_STATUS (Status);
379                 }
380 
381                 /* Already exists, ignore error */
382             }
383             else
384             {
385                 Arg->Common.Node = Info->FieldNode;
386                 Info->FieldBitLength = Arg->Common.Value.Size;
387 
388                 /* Create and initialize an object for the new Field Node */
389 
390                 Status = AcpiExPrepFieldValue (Info);
391                 if (ACPI_FAILURE (Status))
392                 {
393                     return_ACPI_STATUS (Status);
394                 }
395             }
396 
397             /* Keep track of bit position for the next field */
398 
399             Position = (ACPI_INTEGER) Info->FieldBitPosition
400                         + (ACPI_INTEGER) Arg->Common.Value.Size;
401 
402             if (Position > ACPI_UINT32_MAX)
403             {
404                 ACPI_REPORT_ERROR ((
405                     "Field [%4.4s] bit offset too large (> 0xFFFFFFFF)\n",
406                     (char *) &Info->FieldNode->Name));
407                 return_ACPI_STATUS (AE_SUPPORT);
408             }
409 
410             Info->FieldBitPosition += Info->FieldBitLength;
411             break;
412 
413 
414         default:
415 
416             ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
417                 "Invalid opcode in field list: %X\n",
418                 Arg->Common.AmlOpcode));
419             return_ACPI_STATUS (AE_AML_BAD_OPCODE);
420         }
421 
422         Arg = Arg->Common.Next;
423     }
424 
425     return_ACPI_STATUS (AE_OK);
426 }
427 
428 
429 /*******************************************************************************
430  *
431  * FUNCTION:    AcpiDsCreateField
432  *
433  * PARAMETERS:  Op              - Op containing the Field definition and args
434  *              RegionNode      - Object for the containing Operation Region
435  *  `           WalkState       - Current method state
436  *
437  * RETURN:      Status
438  *
439  * DESCRIPTION: Create a new field in the specified operation region
440  *
441  ******************************************************************************/
442 
443 ACPI_STATUS
444 AcpiDsCreateField (
445     ACPI_PARSE_OBJECT       *Op,
446     ACPI_NAMESPACE_NODE     *RegionNode,
447     ACPI_WALK_STATE         *WalkState)
448 {
449     ACPI_STATUS             Status;
450     ACPI_PARSE_OBJECT       *Arg;
451     ACPI_CREATE_FIELD_INFO  Info;
452 
453 
454     ACPI_FUNCTION_TRACE_PTR ("DsCreateField", Op);
455 
456 
457     /* First arg is the name of the parent OpRegion (must already exist) */
458 
459     Arg = Op->Common.Value.Arg;
460     if (!RegionNode)
461     {
462         Status = AcpiNsLookup (WalkState->ScopeInfo, Arg->Common.Value.Name,
463                         ACPI_TYPE_REGION, ACPI_IMODE_EXECUTE,
464                         ACPI_NS_SEARCH_PARENT, WalkState, &RegionNode);
465         if (ACPI_FAILURE (Status))
466         {
467             ACPI_REPORT_NSERROR (Arg->Common.Value.Name, Status);
468             return_ACPI_STATUS (Status);
469         }
470     }
471 
472     /* Second arg is the field flags */
473 
474     Arg = Arg->Common.Next;
475     Info.FieldFlags = (UINT8) Arg->Common.Value.Integer;
476     Info.Attribute = 0;
477 
478     /* Each remaining arg is a Named Field */
479 
480     Info.FieldType = ACPI_TYPE_LOCAL_REGION_FIELD;
481     Info.RegionNode = RegionNode;
482 
483     Status = AcpiDsGetFieldNames (&Info, WalkState, Arg->Common.Next);
484 
485     return_ACPI_STATUS (Status);
486 }
487 
488 
489 /*******************************************************************************
490  *
491  * FUNCTION:    AcpiDsInitFieldObjects
492  *
493  * PARAMETERS:  Op              - Op containing the Field definition and args
494  *  `           WalkState       - Current method state
495  *
496  * RETURN:      Status
497  *
498  * DESCRIPTION: For each "Field Unit" name in the argument list that is
499  *              part of the field declaration, enter the name into the
500  *              namespace.
501  *
502  ******************************************************************************/
503 
504 ACPI_STATUS
505 AcpiDsInitFieldObjects (
506     ACPI_PARSE_OBJECT       *Op,
507     ACPI_WALK_STATE         *WalkState)
508 {
509     ACPI_STATUS             Status;
510     ACPI_PARSE_OBJECT       *Arg = NULL;
511     ACPI_NAMESPACE_NODE     *Node;
512     UINT8                   Type = 0;
513 
514 
515     ACPI_FUNCTION_TRACE_PTR ("DsInitFieldObjects", Op);
516 
517 
518     switch (WalkState->Opcode)
519     {
520     case AML_FIELD_OP:
521         Arg = AcpiPsGetArg (Op, 2);
522         Type = ACPI_TYPE_LOCAL_REGION_FIELD;
523         break;
524 
525     case AML_BANK_FIELD_OP:
526         Arg = AcpiPsGetArg (Op, 4);
527         Type = ACPI_TYPE_LOCAL_BANK_FIELD;
528         break;
529 
530     case AML_INDEX_FIELD_OP:
531         Arg = AcpiPsGetArg (Op, 3);
532         Type = ACPI_TYPE_LOCAL_INDEX_FIELD;
533         break;
534 
535     default:
536         return_ACPI_STATUS (AE_BAD_PARAMETER);
537     }
538 
539     /*
540      * Walk the list of entries in the FieldList
541      */
542     while (Arg)
543     {
544         /* Ignore OFFSET and ACCESSAS terms here */
545 
546         if (Arg->Common.AmlOpcode == AML_INT_NAMEDFIELD_OP)
547         {
548             Status = AcpiNsLookup (WalkState->ScopeInfo,
549                             (char *) &Arg->Named.Name,
550                             Type, ACPI_IMODE_LOAD_PASS1,
551                             ACPI_NS_NO_UPSEARCH | ACPI_NS_DONT_OPEN_SCOPE |
552                             ACPI_NS_ERROR_IF_FOUND,
553                             WalkState, &Node);
554             if (ACPI_FAILURE (Status))
555             {
556                 ACPI_REPORT_NSERROR ((char *) &Arg->Named.Name, Status);
557                 if (Status != AE_ALREADY_EXISTS)
558                 {
559                     return_ACPI_STATUS (Status);
560                 }
561 
562                 /* Name already exists, just ignore this error */
563 
564                 Status = AE_OK;
565             }
566 
567             Arg->Common.Node = Node;
568         }
569 
570         /* Move to next field in the list */
571 
572         Arg = Arg->Common.Next;
573     }
574 
575     return_ACPI_STATUS (AE_OK);
576 }
577 
578 
579 /*******************************************************************************
580  *
581  * FUNCTION:    AcpiDsCreateBankField
582  *
583  * PARAMETERS:  Op              - Op containing the Field definition and args
584  *              RegionNode      - Object for the containing Operation Region
585  *  `           WalkState       - Current method state
586  *
587  * RETURN:      Status
588  *
589  * DESCRIPTION: Create a new bank field in the specified operation region
590  *
591  ******************************************************************************/
592 
593 ACPI_STATUS
594 AcpiDsCreateBankField (
595     ACPI_PARSE_OBJECT       *Op,
596     ACPI_NAMESPACE_NODE     *RegionNode,
597     ACPI_WALK_STATE         *WalkState)
598 {
599     ACPI_STATUS             Status;
600     ACPI_PARSE_OBJECT       *Arg;
601     ACPI_CREATE_FIELD_INFO  Info;
602 
603 
604     ACPI_FUNCTION_TRACE_PTR ("DsCreateBankField", Op);
605 
606 
607     /* First arg is the name of the parent OpRegion (must already exist) */
608 
609     Arg = Op->Common.Value.Arg;
610     if (!RegionNode)
611     {
612         Status = AcpiNsLookup (WalkState->ScopeInfo, Arg->Common.Value.Name,
613                         ACPI_TYPE_REGION, ACPI_IMODE_EXECUTE,
614                         ACPI_NS_SEARCH_PARENT, WalkState, &RegionNode);
615         if (ACPI_FAILURE (Status))
616         {
617             ACPI_REPORT_NSERROR (Arg->Common.Value.Name, Status);
618             return_ACPI_STATUS (Status);
619         }
620     }
621 
622     /* Second arg is the Bank Register (Field) (must already exist) */
623 
624     Arg = Arg->Common.Next;
625     Status = AcpiNsLookup (WalkState->ScopeInfo, Arg->Common.Value.String,
626                     ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
627                     ACPI_NS_SEARCH_PARENT, WalkState, &Info.RegisterNode);
628     if (ACPI_FAILURE (Status))
629     {
630         ACPI_REPORT_NSERROR (Arg->Common.Value.String, Status);
631         return_ACPI_STATUS (Status);
632     }
633 
634     /* Third arg is the BankValue */
635 
636     Arg = Arg->Common.Next;
637     Info.BankValue = (UINT32) Arg->Common.Value.Integer;
638 
639     /* Fourth arg is the field flags */
640 
641     Arg = Arg->Common.Next;
642     Info.FieldFlags = (UINT8) Arg->Common.Value.Integer;
643 
644     /* Each remaining arg is a Named Field */
645 
646     Info.FieldType = ACPI_TYPE_LOCAL_BANK_FIELD;
647     Info.RegionNode = RegionNode;
648 
649     Status = AcpiDsGetFieldNames (&Info, WalkState, Arg->Common.Next);
650 
651     return_ACPI_STATUS (Status);
652 }
653 
654 
655 /*******************************************************************************
656  *
657  * FUNCTION:    AcpiDsCreateIndexField
658  *
659  * PARAMETERS:  Op              - Op containing the Field definition and args
660  *              RegionNode      - Object for the containing Operation Region
661  *  `           WalkState       - Current method state
662  *
663  * RETURN:      Status
664  *
665  * DESCRIPTION: Create a new index field in the specified operation region
666  *
667  ******************************************************************************/
668 
669 ACPI_STATUS
670 AcpiDsCreateIndexField (
671     ACPI_PARSE_OBJECT       *Op,
672     ACPI_NAMESPACE_NODE     *RegionNode,
673     ACPI_WALK_STATE         *WalkState)
674 {
675     ACPI_STATUS             Status;
676     ACPI_PARSE_OBJECT       *Arg;
677     ACPI_CREATE_FIELD_INFO  Info;
678 
679 
680     ACPI_FUNCTION_TRACE_PTR ("DsCreateIndexField", Op);
681 
682 
683     /* First arg is the name of the Index register (must already exist) */
684 
685     Arg = Op->Common.Value.Arg;
686     Status = AcpiNsLookup (WalkState->ScopeInfo, Arg->Common.Value.String,
687                     ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
688                     ACPI_NS_SEARCH_PARENT, WalkState, &Info.RegisterNode);
689     if (ACPI_FAILURE (Status))
690     {
691         ACPI_REPORT_NSERROR (Arg->Common.Value.String, Status);
692         return_ACPI_STATUS (Status);
693     }
694 
695     /* Second arg is the data register (must already exist) */
696 
697     Arg = Arg->Common.Next;
698     Status = AcpiNsLookup (WalkState->ScopeInfo, Arg->Common.Value.String,
699                     ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
700                     ACPI_NS_SEARCH_PARENT, WalkState, &Info.DataRegisterNode);
701     if (ACPI_FAILURE (Status))
702     {
703         ACPI_REPORT_NSERROR (Arg->Common.Value.String, Status);
704         return_ACPI_STATUS (Status);
705     }
706 
707     /* Next arg is the field flags */
708 
709     Arg = Arg->Common.Next;
710     Info.FieldFlags = (UINT8) Arg->Common.Value.Integer;
711 
712     /* Each remaining arg is a Named Field */
713 
714     Info.FieldType = ACPI_TYPE_LOCAL_INDEX_FIELD;
715     Info.RegionNode = RegionNode;
716 
717     Status = AcpiDsGetFieldNames (&Info, WalkState, Arg->Common.Next);
718 
719     return_ACPI_STATUS (Status);
720 }
721 
722 
723