xref: /dflybsd-src/sys/contrib/dev/acpica/source/components/executer/excreate.c (revision 1093ca8198152f41873a8d1e4af82ccd1b7ac52a)
1 /******************************************************************************
2  *
3  * Module Name: excreate - Named object creation
4  *
5  *****************************************************************************/
6 
7 /******************************************************************************
8  *
9  * 1. Copyright Notice
10  *
11  * Some or all of this work - Copyright (c) 1999 - 2017, Intel Corp.
12  * All rights reserved.
13  *
14  * 2. License
15  *
16  * 2.1. This is your license from Intel Corp. under its intellectual property
17  * rights. You may have additional license terms from the party that provided
18  * you this software, covering your right to use that party's intellectual
19  * property rights.
20  *
21  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
22  * copy of the source code appearing in this file ("Covered Code") an
23  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
24  * base code distributed originally by Intel ("Original Intel Code") to copy,
25  * make derivatives, distribute, use and display any portion of the Covered
26  * Code in any form, with the right to sublicense such rights; and
27  *
28  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
29  * license (with the right to sublicense), under only those claims of Intel
30  * patents that are infringed by the Original Intel Code, to make, use, sell,
31  * offer to sell, and import the Covered Code and derivative works thereof
32  * solely to the minimum extent necessary to exercise the above copyright
33  * license, and in no event shall the patent license extend to any additions
34  * to or modifications of the Original Intel Code. No other license or right
35  * is granted directly or by implication, estoppel or otherwise;
36  *
37  * The above copyright and patent license is granted only if the following
38  * conditions are met:
39  *
40  * 3. Conditions
41  *
42  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
43  * Redistribution of source code of any substantial portion of the Covered
44  * Code or modification with rights to further distribute source must include
45  * the above Copyright Notice, the above License, this list of Conditions,
46  * and the following Disclaimer and Export Compliance provision. In addition,
47  * Licensee must cause all Covered Code to which Licensee contributes to
48  * contain a file documenting the changes Licensee made to create that Covered
49  * Code and the date of any change. Licensee must include in that file the
50  * documentation of any changes made by any predecessor Licensee. Licensee
51  * must include a prominent statement that the modification is derived,
52  * directly or indirectly, from Original Intel Code.
53  *
54  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
55  * Redistribution of source code of any substantial portion of the Covered
56  * Code or modification without rights to further distribute source must
57  * include the following Disclaimer and Export Compliance provision in the
58  * documentation and/or other materials provided with distribution. In
59  * addition, Licensee may not authorize further sublicense of source of any
60  * portion of the Covered Code, and must include terms to the effect that the
61  * license from Licensee to its licensee is limited to the intellectual
62  * property embodied in the software Licensee provides to its licensee, and
63  * not to intellectual property embodied in modifications its licensee may
64  * make.
65  *
66  * 3.3. Redistribution of Executable. Redistribution in executable form of any
67  * substantial portion of the Covered Code or modification must reproduce the
68  * above Copyright Notice, and the following Disclaimer and Export Compliance
69  * provision in the documentation and/or other materials provided with the
70  * distribution.
71  *
72  * 3.4. Intel retains all right, title, and interest in and to the Original
73  * Intel Code.
74  *
75  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
76  * Intel shall be used in advertising or otherwise to promote the sale, use or
77  * other dealings in products derived from or relating to the Covered Code
78  * without prior written authorization from Intel.
79  *
80  * 4. Disclaimer and Export Compliance
81  *
82  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
83  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
84  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
85  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
86 
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  * Alternatively, you may choose to be licensed under the terms of the
118  * following license:
119  *
120  * Redistribution and use in source and binary forms, with or without
121  * modification, are permitted provided that the following conditions
122  * are met:
123  * 1. Redistributions of source code must retain the above copyright
124  *    notice, this list of conditions, and the following disclaimer,
125  *    without modification.
126  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
127  *    substantially similar to the "NO WARRANTY" disclaimer below
128  *    ("Disclaimer") and any redistribution must be conditioned upon
129  *    including a substantially similar Disclaimer requirement for further
130  *    binary redistribution.
131  * 3. Neither the names of the above-listed copyright holders nor the names
132  *    of any contributors may be used to endorse or promote products derived
133  *    from this software without specific prior written permission.
134  *
135  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
136  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
137  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
138  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
139  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
140  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
141  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
142  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
143  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
144  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
145  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
146  *
147  * Alternatively, you may choose to be licensed under the terms of the
148  * GNU General Public License ("GPL") version 2 as published by the Free
149  * Software Foundation.
150  *
151  *****************************************************************************/
152 
153 #include "acpi.h"
154 #include "accommon.h"
155 #include "acinterp.h"
156 #include "amlcode.h"
157 #include "acnamesp.h"
158 
159 
160 #define _COMPONENT          ACPI_EXECUTER
161         ACPI_MODULE_NAME    ("excreate")
162 
163 
164 #ifndef ACPI_NO_METHOD_EXECUTION
165 /*******************************************************************************
166  *
167  * FUNCTION:    AcpiExCreateAlias
168  *
169  * PARAMETERS:  WalkState            - Current state, contains operands
170  *
171  * RETURN:      Status
172  *
173  * DESCRIPTION: Create a new named alias
174  *
175  ******************************************************************************/
176 
177 ACPI_STATUS
178 AcpiExCreateAlias (
179     ACPI_WALK_STATE         *WalkState)
180 {
181     ACPI_NAMESPACE_NODE     *TargetNode;
182     ACPI_NAMESPACE_NODE     *AliasNode;
183     ACPI_STATUS             Status = AE_OK;
184 
185 
186     ACPI_FUNCTION_TRACE (ExCreateAlias);
187 
188 
189     /* Get the source/alias operands (both namespace nodes) */
190 
191     AliasNode =  (ACPI_NAMESPACE_NODE *) WalkState->Operands[0];
192     TargetNode = (ACPI_NAMESPACE_NODE *) WalkState->Operands[1];
193 
194     if ((TargetNode->Type == ACPI_TYPE_LOCAL_ALIAS)  ||
195         (TargetNode->Type == ACPI_TYPE_LOCAL_METHOD_ALIAS))
196     {
197         /*
198          * Dereference an existing alias so that we don't create a chain
199          * of aliases. With this code, we guarantee that an alias is
200          * always exactly one level of indirection away from the
201          * actual aliased name.
202          */
203         TargetNode = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, TargetNode->Object);
204     }
205 
206     /* Ensure that the target node is valid */
207     if (!TargetNode)
208     {
209         return_ACPI_STATUS (AE_NULL_OBJECT);
210     }
211 
212     /*
213      * For objects that can never change (i.e., the NS node will
214      * permanently point to the same object), we can simply attach
215      * the object to the new NS node. For other objects (such as
216      * Integers, buffers, etc.), we have to point the Alias node
217      * to the original Node.
218      */
219     switch (TargetNode->Type)
220     {
221 
222     /* For these types, the sub-object can change dynamically via a Store */
223 
224     case ACPI_TYPE_INTEGER:
225     case ACPI_TYPE_STRING:
226     case ACPI_TYPE_BUFFER:
227     case ACPI_TYPE_PACKAGE:
228     case ACPI_TYPE_BUFFER_FIELD:
229     /*
230      * These types open a new scope, so we need the NS node in order to access
231      * any children.
232      */
233     case ACPI_TYPE_DEVICE:
234     case ACPI_TYPE_POWER:
235     case ACPI_TYPE_PROCESSOR:
236     case ACPI_TYPE_THERMAL:
237     case ACPI_TYPE_LOCAL_SCOPE:
238         /*
239          * The new alias has the type ALIAS and points to the original
240          * NS node, not the object itself.
241          */
242         AliasNode->Type = ACPI_TYPE_LOCAL_ALIAS;
243         AliasNode->Object = ACPI_CAST_PTR (ACPI_OPERAND_OBJECT, TargetNode);
244         break;
245 
246     case ACPI_TYPE_METHOD:
247         /*
248          * Control method aliases need to be differentiated
249          */
250         AliasNode->Type = ACPI_TYPE_LOCAL_METHOD_ALIAS;
251         AliasNode->Object = ACPI_CAST_PTR (ACPI_OPERAND_OBJECT, TargetNode);
252         break;
253 
254     default:
255 
256         /* Attach the original source object to the new Alias Node */
257 
258         /*
259          * The new alias assumes the type of the target, and it points
260          * to the same object. The reference count of the object has an
261          * additional reference to prevent deletion out from under either the
262          * target node or the alias Node
263          */
264         Status = AcpiNsAttachObject (AliasNode,
265             AcpiNsGetAttachedObject (TargetNode), TargetNode->Type);
266         break;
267     }
268 
269     /* Since both operands are Nodes, we don't need to delete them */
270 
271     return_ACPI_STATUS (Status);
272 }
273 
274 
275 /*******************************************************************************
276  *
277  * FUNCTION:    AcpiExCreateEvent
278  *
279  * PARAMETERS:  WalkState           - Current state
280  *
281  * RETURN:      Status
282  *
283  * DESCRIPTION: Create a new event object
284  *
285  ******************************************************************************/
286 
287 ACPI_STATUS
288 AcpiExCreateEvent (
289     ACPI_WALK_STATE         *WalkState)
290 {
291     ACPI_STATUS             Status;
292     ACPI_OPERAND_OBJECT     *ObjDesc;
293 
294 
295     ACPI_FUNCTION_TRACE (ExCreateEvent);
296 
297 
298     ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_EVENT);
299     if (!ObjDesc)
300     {
301         Status = AE_NO_MEMORY;
302         goto Cleanup;
303     }
304 
305     /*
306      * Create the actual OS semaphore, with zero initial units -- meaning
307      * that the event is created in an unsignalled state
308      */
309     Status = AcpiOsCreateSemaphore (ACPI_NO_UNIT_LIMIT, 0,
310         &ObjDesc->Event.OsSemaphore);
311     if (ACPI_FAILURE (Status))
312     {
313         goto Cleanup;
314     }
315 
316     /* Attach object to the Node */
317 
318     Status = AcpiNsAttachObject (
319         (ACPI_NAMESPACE_NODE *) WalkState->Operands[0],
320         ObjDesc, ACPI_TYPE_EVENT);
321 
322 Cleanup:
323     /*
324      * Remove local reference to the object (on error, will cause deletion
325      * of both object and semaphore if present.)
326      */
327     AcpiUtRemoveReference (ObjDesc);
328     return_ACPI_STATUS (Status);
329 }
330 
331 
332 /*******************************************************************************
333  *
334  * FUNCTION:    AcpiExCreateMutex
335  *
336  * PARAMETERS:  WalkState           - Current state
337  *
338  * RETURN:      Status
339  *
340  * DESCRIPTION: Create a new mutex object
341  *
342  *              Mutex (Name[0], SyncLevel[1])
343  *
344  ******************************************************************************/
345 
346 ACPI_STATUS
347 AcpiExCreateMutex (
348     ACPI_WALK_STATE         *WalkState)
349 {
350     ACPI_STATUS             Status = AE_OK;
351     ACPI_OPERAND_OBJECT     *ObjDesc;
352 
353 
354     ACPI_FUNCTION_TRACE_PTR (ExCreateMutex, ACPI_WALK_OPERANDS);
355 
356 
357     /* Create the new mutex object */
358 
359     ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_MUTEX);
360     if (!ObjDesc)
361     {
362         Status = AE_NO_MEMORY;
363         goto Cleanup;
364     }
365 
366     /* Create the actual OS Mutex */
367 
368     Status = AcpiOsCreateMutex (&ObjDesc->Mutex.OsMutex);
369     if (ACPI_FAILURE (Status))
370     {
371         goto Cleanup;
372     }
373 
374     /* Init object and attach to NS node */
375 
376     ObjDesc->Mutex.SyncLevel = (UINT8) WalkState->Operands[1]->Integer.Value;
377     ObjDesc->Mutex.Node = (ACPI_NAMESPACE_NODE *) WalkState->Operands[0];
378 
379     Status = AcpiNsAttachObject (
380         ObjDesc->Mutex.Node, ObjDesc, ACPI_TYPE_MUTEX);
381 
382 
383 Cleanup:
384     /*
385      * Remove local reference to the object (on error, will cause deletion
386      * of both object and semaphore if present.)
387      */
388     AcpiUtRemoveReference (ObjDesc);
389     return_ACPI_STATUS (Status);
390 }
391 
392 
393 /*******************************************************************************
394  *
395  * FUNCTION:    AcpiExCreateRegion
396  *
397  * PARAMETERS:  AmlStart            - Pointer to the region declaration AML
398  *              AmlLength           - Max length of the declaration AML
399  *              SpaceId             - Address space ID for the region
400  *              WalkState           - Current state
401  *
402  * RETURN:      Status
403  *
404  * DESCRIPTION: Create a new operation region object
405  *
406  ******************************************************************************/
407 
408 ACPI_STATUS
409 AcpiExCreateRegion (
410     UINT8                   *AmlStart,
411     UINT32                  AmlLength,
412     UINT8                   SpaceId,
413     ACPI_WALK_STATE         *WalkState)
414 {
415     ACPI_STATUS             Status;
416     ACPI_OPERAND_OBJECT     *ObjDesc;
417     ACPI_NAMESPACE_NODE     *Node;
418     ACPI_OPERAND_OBJECT     *RegionObj2;
419 
420 
421     ACPI_FUNCTION_TRACE (ExCreateRegion);
422 
423 
424     /* Get the Namespace Node */
425 
426     Node = WalkState->Op->Common.Node;
427 
428     /*
429      * If the region object is already attached to this node,
430      * just return
431      */
432     if (AcpiNsGetAttachedObject (Node))
433     {
434         return_ACPI_STATUS (AE_OK);
435     }
436 
437     /*
438      * Space ID must be one of the predefined IDs, or in the user-defined
439      * range
440      */
441     if (!AcpiIsValidSpaceId (SpaceId))
442     {
443         /*
444          * Print an error message, but continue. We don't want to abort
445          * a table load for this exception. Instead, if the region is
446          * actually used at runtime, abort the executing method.
447          */
448         ACPI_ERROR ((AE_INFO,
449             "Invalid/unknown Address Space ID: 0x%2.2X", SpaceId));
450     }
451 
452     ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "Region Type - %s (0x%X)\n",
453         AcpiUtGetRegionName (SpaceId), SpaceId));
454 
455     /* Create the region descriptor */
456 
457     ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_REGION);
458     if (!ObjDesc)
459     {
460         Status = AE_NO_MEMORY;
461         goto Cleanup;
462     }
463 
464     /*
465      * Remember location in AML stream of address & length
466      * operands since they need to be evaluated at run time.
467      */
468     RegionObj2 = AcpiNsGetSecondaryObject (ObjDesc);
469     RegionObj2->Extra.AmlStart = AmlStart;
470     RegionObj2->Extra.AmlLength = AmlLength;
471     RegionObj2->Extra.Method_REG = NULL;
472     if (WalkState->ScopeInfo)
473     {
474         RegionObj2->Extra.ScopeNode = WalkState->ScopeInfo->Scope.Node;
475     }
476     else
477     {
478         RegionObj2->Extra.ScopeNode = Node;
479     }
480 
481     /* Init the region from the operands */
482 
483     ObjDesc->Region.SpaceId = SpaceId;
484     ObjDesc->Region.Address = 0;
485     ObjDesc->Region.Length = 0;
486     ObjDesc->Region.Node = Node;
487     ObjDesc->Region.Handler = NULL;
488     ObjDesc->Common.Flags &=
489         ~(AOPOBJ_SETUP_COMPLETE | AOPOBJ_REG_CONNECTED |
490           AOPOBJ_OBJECT_INITIALIZED);
491 
492     /* Install the new region object in the parent Node */
493 
494     Status = AcpiNsAttachObject (Node, ObjDesc, ACPI_TYPE_REGION);
495 
496 
497 Cleanup:
498 
499     /* Remove local reference to the object */
500 
501     AcpiUtRemoveReference (ObjDesc);
502     return_ACPI_STATUS (Status);
503 }
504 
505 
506 /*******************************************************************************
507  *
508  * FUNCTION:    AcpiExCreateProcessor
509  *
510  * PARAMETERS:  WalkState           - Current state
511  *
512  * RETURN:      Status
513  *
514  * DESCRIPTION: Create a new processor object and populate the fields
515  *
516  *              Processor (Name[0], CpuID[1], PblockAddr[2], PblockLength[3])
517  *
518  ******************************************************************************/
519 
520 ACPI_STATUS
521 AcpiExCreateProcessor (
522     ACPI_WALK_STATE         *WalkState)
523 {
524     ACPI_OPERAND_OBJECT     **Operand = &WalkState->Operands[0];
525     ACPI_OPERAND_OBJECT     *ObjDesc;
526     ACPI_STATUS             Status;
527 
528 
529     ACPI_FUNCTION_TRACE_PTR (ExCreateProcessor, WalkState);
530 
531 
532     /* Create the processor object */
533 
534     ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_PROCESSOR);
535     if (!ObjDesc)
536     {
537         return_ACPI_STATUS (AE_NO_MEMORY);
538     }
539 
540     /* Initialize the processor object from the operands */
541 
542     ObjDesc->Processor.ProcId = (UINT8) Operand[1]->Integer.Value;
543     ObjDesc->Processor.Length = (UINT8) Operand[3]->Integer.Value;
544     ObjDesc->Processor.Address = (ACPI_IO_ADDRESS) Operand[2]->Integer.Value;
545 
546     /* Install the processor object in the parent Node */
547 
548     Status = AcpiNsAttachObject ((ACPI_NAMESPACE_NODE *) Operand[0],
549         ObjDesc, ACPI_TYPE_PROCESSOR);
550 
551     /* Remove local reference to the object */
552 
553     AcpiUtRemoveReference (ObjDesc);
554     return_ACPI_STATUS (Status);
555 }
556 
557 
558 /*******************************************************************************
559  *
560  * FUNCTION:    AcpiExCreatePowerResource
561  *
562  * PARAMETERS:  WalkState           - Current state
563  *
564  * RETURN:      Status
565  *
566  * DESCRIPTION: Create a new PowerResource object and populate the fields
567  *
568  *              PowerResource (Name[0], SystemLevel[1], ResourceOrder[2])
569  *
570  ******************************************************************************/
571 
572 ACPI_STATUS
573 AcpiExCreatePowerResource (
574     ACPI_WALK_STATE         *WalkState)
575 {
576     ACPI_OPERAND_OBJECT     **Operand = &WalkState->Operands[0];
577     ACPI_STATUS             Status;
578     ACPI_OPERAND_OBJECT     *ObjDesc;
579 
580 
581     ACPI_FUNCTION_TRACE_PTR (ExCreatePowerResource, WalkState);
582 
583 
584     /* Create the power resource object */
585 
586     ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_POWER);
587     if (!ObjDesc)
588     {
589         return_ACPI_STATUS (AE_NO_MEMORY);
590     }
591 
592     /* Initialize the power object from the operands */
593 
594     ObjDesc->PowerResource.SystemLevel = (UINT8) Operand[1]->Integer.Value;
595     ObjDesc->PowerResource.ResourceOrder = (UINT16) Operand[2]->Integer.Value;
596 
597     /* Install the  power resource object in the parent Node */
598 
599     Status = AcpiNsAttachObject ((ACPI_NAMESPACE_NODE *) Operand[0],
600         ObjDesc, ACPI_TYPE_POWER);
601 
602     /* Remove local reference to the object */
603 
604     AcpiUtRemoveReference (ObjDesc);
605     return_ACPI_STATUS (Status);
606 }
607 #endif
608 
609 
610 /*******************************************************************************
611  *
612  * FUNCTION:    AcpiExCreateMethod
613  *
614  * PARAMETERS:  AmlStart        - First byte of the method's AML
615  *              AmlLength       - AML byte count for this method
616  *              WalkState       - Current state
617  *
618  * RETURN:      Status
619  *
620  * DESCRIPTION: Create a new method object
621  *
622  ******************************************************************************/
623 
624 ACPI_STATUS
625 AcpiExCreateMethod (
626     UINT8                   *AmlStart,
627     UINT32                  AmlLength,
628     ACPI_WALK_STATE         *WalkState)
629 {
630     ACPI_OPERAND_OBJECT     **Operand = &WalkState->Operands[0];
631     ACPI_OPERAND_OBJECT     *ObjDesc;
632     ACPI_STATUS             Status;
633     UINT8                   MethodFlags;
634 
635 
636     ACPI_FUNCTION_TRACE_PTR (ExCreateMethod, WalkState);
637 
638 
639     /* Create a new method object */
640 
641     ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_METHOD);
642     if (!ObjDesc)
643     {
644        Status = AE_NO_MEMORY;
645        goto Exit;
646     }
647 
648     /* Save the method's AML pointer and length  */
649 
650     ObjDesc->Method.AmlStart = AmlStart;
651     ObjDesc->Method.AmlLength = AmlLength;
652     ObjDesc->Method.Node = Operand[0];
653 
654     /*
655      * Disassemble the method flags. Split off the ArgCount, Serialized
656      * flag, and SyncLevel for efficiency.
657      */
658     MethodFlags = (UINT8) Operand[1]->Integer.Value;
659     ObjDesc->Method.ParamCount = (UINT8)
660         (MethodFlags & AML_METHOD_ARG_COUNT);
661 
662     /*
663      * Get the SyncLevel. If method is serialized, a mutex will be
664      * created for this method when it is parsed.
665      */
666     if (MethodFlags & AML_METHOD_SERIALIZED)
667     {
668         ObjDesc->Method.InfoFlags = ACPI_METHOD_SERIALIZED;
669 
670         /*
671          * ACPI 1.0: SyncLevel = 0
672          * ACPI 2.0: SyncLevel = SyncLevel in method declaration
673          */
674         ObjDesc->Method.SyncLevel = (UINT8)
675             ((MethodFlags & AML_METHOD_SYNC_LEVEL) >> 4);
676     }
677 
678     /* Attach the new object to the method Node */
679 
680     Status = AcpiNsAttachObject ((ACPI_NAMESPACE_NODE *) Operand[0],
681         ObjDesc, ACPI_TYPE_METHOD);
682 
683     /* Remove local reference to the object */
684 
685     AcpiUtRemoveReference (ObjDesc);
686 
687 Exit:
688     /* Remove a reference to the operand */
689 
690     AcpiUtRemoveReference (Operand[1]);
691     return_ACPI_STATUS (Status);
692 }
693