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      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 - 2025, 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 /*******************************************************************************
    165  *
    166  * FUNCTION:    AcpiExCreateAlias
    167  *
    168  * PARAMETERS:  WalkState            - Current state, contains operands
    169  *
    170  * RETURN:      Status
    171  *
    172  * DESCRIPTION: Create a new named alias
    173  *
    174  ******************************************************************************/
    175 
    176 ACPI_STATUS
    177 AcpiExCreateAlias (
    178     ACPI_WALK_STATE         *WalkState)
    179 {
    180     ACPI_NAMESPACE_NODE     *TargetNode;
    181     ACPI_NAMESPACE_NODE     *AliasNode;
    182     ACPI_STATUS             Status = AE_OK;
    183 
    184 
    185     ACPI_FUNCTION_TRACE (ExCreateAlias);
    186 
    187 
    188     /* Get the source/alias operands (both namespace nodes) */
    189 
    190     AliasNode =  (ACPI_NAMESPACE_NODE *) WalkState->Operands[0];
    191     TargetNode = (ACPI_NAMESPACE_NODE *) WalkState->Operands[1];
    192 
    193     if ((TargetNode->Type == ACPI_TYPE_LOCAL_ALIAS)  ||
    194         (TargetNode->Type == ACPI_TYPE_LOCAL_METHOD_ALIAS))
    195     {
    196         /*
    197          * Dereference an existing alias so that we don't create a chain
    198          * of aliases. With this code, we guarantee that an alias is
    199          * always exactly one level of indirection away from the
    200          * actual aliased name.
    201          */
    202         TargetNode = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, TargetNode->Object);
    203     }
    204 
    205     /* Ensure that the target node is valid */
    206 
    207     if (!TargetNode)
    208     {
    209         return_ACPI_STATUS (AE_NULL_OBJECT);
    210     }
    211 
    212     /* Construct the alias object (a namespace node) */
    213 
    214     switch (TargetNode->Type)
    215     {
    216     case ACPI_TYPE_METHOD:
    217         /*
    218          * Control method aliases need to be differentiated with
    219          * a special type
    220          */
    221         AliasNode->Type = ACPI_TYPE_LOCAL_METHOD_ALIAS;
    222         break;
    223 
    224     default:
    225         /*
    226          * All other object types.
    227          *
    228          * The new alias has the type ALIAS and points to the original
    229          * NS node, not the object itself.
    230          */
    231         AliasNode->Type = ACPI_TYPE_LOCAL_ALIAS;
    232         AliasNode->Object = ACPI_CAST_PTR (ACPI_OPERAND_OBJECT, TargetNode);
    233         break;
    234     }
    235 
    236     /* Since both operands are Nodes, we don't need to delete them */
    237 
    238     AliasNode->Object = ACPI_CAST_PTR (ACPI_OPERAND_OBJECT, TargetNode);
    239     return_ACPI_STATUS (Status);
    240 }
    241 
    242 
    243 /*******************************************************************************
    244  *
    245  * FUNCTION:    AcpiExCreateEvent
    246  *
    247  * PARAMETERS:  WalkState           - Current state
    248  *
    249  * RETURN:      Status
    250  *
    251  * DESCRIPTION: Create a new event object
    252  *
    253  ******************************************************************************/
    254 
    255 ACPI_STATUS
    256 AcpiExCreateEvent (
    257     ACPI_WALK_STATE         *WalkState)
    258 {
    259     ACPI_STATUS             Status;
    260     ACPI_OPERAND_OBJECT     *ObjDesc;
    261 
    262 
    263     ACPI_FUNCTION_TRACE (ExCreateEvent);
    264 
    265 
    266     ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_EVENT);
    267     if (!ObjDesc)
    268     {
    269         Status = AE_NO_MEMORY;
    270         goto Cleanup;
    271     }
    272 
    273     /*
    274      * Create the actual OS semaphore, with zero initial units -- meaning
    275      * that the event is created in an unsignalled state
    276      */
    277     Status = AcpiOsCreateSemaphore (ACPI_NO_UNIT_LIMIT, 0,
    278         &ObjDesc->Event.OsSemaphore);
    279     if (ACPI_FAILURE (Status))
    280     {
    281         goto Cleanup;
    282     }
    283 
    284     /* Attach object to the Node */
    285 
    286     Status = AcpiNsAttachObject (
    287         (ACPI_NAMESPACE_NODE *) WalkState->Operands[0],
    288         ObjDesc, ACPI_TYPE_EVENT);
    289 
    290 Cleanup:
    291     /*
    292      * Remove local reference to the object (on error, will cause deletion
    293      * of both object and semaphore if present.)
    294      */
    295     AcpiUtRemoveReference (ObjDesc);
    296     return_ACPI_STATUS (Status);
    297 }
    298 
    299 
    300 /*******************************************************************************
    301  *
    302  * FUNCTION:    AcpiExCreateMutex
    303  *
    304  * PARAMETERS:  WalkState           - Current state
    305  *
    306  * RETURN:      Status
    307  *
    308  * DESCRIPTION: Create a new mutex object
    309  *
    310  *              Mutex (Name[0], SyncLevel[1])
    311  *
    312  ******************************************************************************/
    313 
    314 ACPI_STATUS
    315 AcpiExCreateMutex (
    316     ACPI_WALK_STATE         *WalkState)
    317 {
    318     ACPI_STATUS             Status = AE_OK;
    319     ACPI_OPERAND_OBJECT     *ObjDesc;
    320 
    321 
    322     ACPI_FUNCTION_TRACE_PTR (ExCreateMutex, ACPI_WALK_OPERANDS);
    323 
    324 
    325     /* Create the new mutex object */
    326 
    327     ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_MUTEX);
    328     if (!ObjDesc)
    329     {
    330         Status = AE_NO_MEMORY;
    331         goto Cleanup;
    332     }
    333 
    334     /* Create the actual OS Mutex */
    335 
    336     Status = AcpiOsCreateMutex (&ObjDesc->Mutex.OsMutex);
    337     if (ACPI_FAILURE (Status))
    338     {
    339         goto Cleanup;
    340     }
    341 
    342     /* Init object and attach to NS node */
    343 
    344     ObjDesc->Mutex.SyncLevel = (UINT8) WalkState->Operands[1]->Integer.Value;
    345     ObjDesc->Mutex.Node = (ACPI_NAMESPACE_NODE *) WalkState->Operands[0];
    346 
    347     Status = AcpiNsAttachObject (
    348         ObjDesc->Mutex.Node, ObjDesc, ACPI_TYPE_MUTEX);
    349 
    350 
    351 Cleanup:
    352     /*
    353      * Remove local reference to the object (on error, will cause deletion
    354      * of both object and semaphore if present.)
    355      */
    356     AcpiUtRemoveReference (ObjDesc);
    357     return_ACPI_STATUS (Status);
    358 }
    359 
    360 
    361 /*******************************************************************************
    362  *
    363  * FUNCTION:    AcpiExCreateRegion
    364  *
    365  * PARAMETERS:  AmlStart            - Pointer to the region declaration AML
    366  *              AmlLength           - Max length of the declaration AML
    367  *              SpaceId             - Address space ID for the region
    368  *              WalkState           - Current state
    369  *
    370  * RETURN:      Status
    371  *
    372  * DESCRIPTION: Create a new operation region object
    373  *
    374  ******************************************************************************/
    375 
    376 ACPI_STATUS
    377 AcpiExCreateRegion (
    378     UINT8                   *AmlStart,
    379     UINT32                  AmlLength,
    380     UINT8                   SpaceId,
    381     ACPI_WALK_STATE         *WalkState)
    382 {
    383     ACPI_STATUS             Status;
    384     ACPI_OPERAND_OBJECT     *ObjDesc;
    385     ACPI_NAMESPACE_NODE     *Node;
    386     ACPI_OPERAND_OBJECT     *RegionObj2;
    387 
    388 
    389     ACPI_FUNCTION_TRACE (ExCreateRegion);
    390 
    391 
    392     /* Get the Namespace Node */
    393 
    394     Node = WalkState->Op->Common.Node;
    395 
    396     /*
    397      * If the region object is already attached to this node,
    398      * just return
    399      */
    400     if (AcpiNsGetAttachedObject (Node))
    401     {
    402         return_ACPI_STATUS (AE_OK);
    403     }
    404 
    405     /*
    406      * Space ID must be one of the predefined IDs, or in the user-defined
    407      * range
    408      */
    409     if (!AcpiIsValidSpaceId (SpaceId))
    410     {
    411         /*
    412          * Print an error message, but continue. We don't want to abort
    413          * a table load for this exception. Instead, if the region is
    414          * actually used at runtime, abort the executing method.
    415          */
    416         ACPI_ERROR ((AE_INFO,
    417             "Invalid/unknown Address Space ID: 0x%2.2X", SpaceId));
    418     }
    419 
    420     ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "Region Type - %s (0x%X)\n",
    421         AcpiUtGetRegionName (SpaceId), SpaceId));
    422 
    423     /* Create the region descriptor */
    424 
    425     ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_REGION);
    426     if (!ObjDesc)
    427     {
    428         Status = AE_NO_MEMORY;
    429         goto Cleanup;
    430     }
    431 
    432     /*
    433      * Remember location in AML stream of address & length
    434      * operands since they need to be evaluated at run time.
    435      */
    436     RegionObj2 = AcpiNsGetSecondaryObject (ObjDesc);
    437     RegionObj2->Extra.AmlStart = AmlStart;
    438     RegionObj2->Extra.AmlLength = AmlLength;
    439     RegionObj2->Extra.Method_REG = NULL;
    440     if (WalkState->ScopeInfo)
    441     {
    442         RegionObj2->Extra.ScopeNode = WalkState->ScopeInfo->Scope.Node;
    443     }
    444     else
    445     {
    446         RegionObj2->Extra.ScopeNode = Node;
    447     }
    448 
    449     /* Init the region from the operands */
    450 
    451     ObjDesc->Region.SpaceId = SpaceId;
    452     ObjDesc->Region.Address = 0;
    453     ObjDesc->Region.Length = 0;
    454     ObjDesc->Region.Pointer = NULL;
    455     ObjDesc->Region.Node = Node;
    456     ObjDesc->Region.Handler = NULL;
    457     ObjDesc->Common.Flags &=
    458         ~(AOPOBJ_SETUP_COMPLETE | AOPOBJ_REG_CONNECTED |
    459           AOPOBJ_OBJECT_INITIALIZED);
    460 
    461     /* Install the new region object in the parent Node */
    462 
    463     Status = AcpiNsAttachObject (Node, ObjDesc, ACPI_TYPE_REGION);
    464 
    465 
    466 Cleanup:
    467 
    468     /* Remove local reference to the object */
    469 
    470     AcpiUtRemoveReference (ObjDesc);
    471     return_ACPI_STATUS (Status);
    472 }
    473 
    474 
    475 /*******************************************************************************
    476  *
    477  * FUNCTION:    AcpiExCreateProcessor
    478  *
    479  * PARAMETERS:  WalkState           - Current state
    480  *
    481  * RETURN:      Status
    482  *
    483  * DESCRIPTION: Create a new processor object and populate the fields
    484  *
    485  *              Processor (Name[0], CpuID[1], PblockAddr[2], PblockLength[3])
    486  *
    487  ******************************************************************************/
    488 
    489 ACPI_STATUS
    490 AcpiExCreateProcessor (
    491     ACPI_WALK_STATE         *WalkState)
    492 {
    493     ACPI_OPERAND_OBJECT     **Operand = &WalkState->Operands[0];
    494     ACPI_OPERAND_OBJECT     *ObjDesc;
    495     ACPI_STATUS             Status;
    496 
    497 
    498     ACPI_FUNCTION_TRACE_PTR (ExCreateProcessor, WalkState);
    499 
    500 
    501     /* Create the processor object */
    502 
    503     ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_PROCESSOR);
    504     if (!ObjDesc)
    505     {
    506         return_ACPI_STATUS (AE_NO_MEMORY);
    507     }
    508 
    509     /* Initialize the processor object from the operands */
    510 
    511     ObjDesc->Processor.ProcId = (UINT8) Operand[1]->Integer.Value;
    512     ObjDesc->Processor.Length = (UINT8) Operand[3]->Integer.Value;
    513     ObjDesc->Processor.Address = (ACPI_IO_ADDRESS) Operand[2]->Integer.Value;
    514 
    515     /* Install the processor object in the parent Node */
    516 
    517     Status = AcpiNsAttachObject ((ACPI_NAMESPACE_NODE *) Operand[0],
    518         ObjDesc, ACPI_TYPE_PROCESSOR);
    519 
    520     /* Remove local reference to the object */
    521 
    522     AcpiUtRemoveReference (ObjDesc);
    523     return_ACPI_STATUS (Status);
    524 }
    525 
    526 
    527 /*******************************************************************************
    528  *
    529  * FUNCTION:    AcpiExCreatePowerResource
    530  *
    531  * PARAMETERS:  WalkState           - Current state
    532  *
    533  * RETURN:      Status
    534  *
    535  * DESCRIPTION: Create a new PowerResource object and populate the fields
    536  *
    537  *              PowerResource (Name[0], SystemLevel[1], ResourceOrder[2])
    538  *
    539  ******************************************************************************/
    540 
    541 ACPI_STATUS
    542 AcpiExCreatePowerResource (
    543     ACPI_WALK_STATE         *WalkState)
    544 {
    545     ACPI_OPERAND_OBJECT     **Operand = &WalkState->Operands[0];
    546     ACPI_STATUS             Status;
    547     ACPI_OPERAND_OBJECT     *ObjDesc;
    548 
    549 
    550     ACPI_FUNCTION_TRACE_PTR (ExCreatePowerResource, WalkState);
    551 
    552 
    553     /* Create the power resource object */
    554 
    555     ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_POWER);
    556     if (!ObjDesc)
    557     {
    558         return_ACPI_STATUS (AE_NO_MEMORY);
    559     }
    560 
    561     /* Initialize the power object from the operands */
    562 
    563     ObjDesc->PowerResource.SystemLevel = (UINT8) Operand[1]->Integer.Value;
    564     ObjDesc->PowerResource.ResourceOrder = (UINT16) Operand[2]->Integer.Value;
    565 
    566     /* Install the  power resource object in the parent Node */
    567 
    568     Status = AcpiNsAttachObject ((ACPI_NAMESPACE_NODE *) Operand[0],
    569         ObjDesc, ACPI_TYPE_POWER);
    570 
    571     /* Remove local reference to the object */
    572 
    573     AcpiUtRemoveReference (ObjDesc);
    574     return_ACPI_STATUS (Status);
    575 }
    576 
    577 
    578 /*******************************************************************************
    579  *
    580  * FUNCTION:    AcpiExCreateMethod
    581  *
    582  * PARAMETERS:  AmlStart        - First byte of the method's AML
    583  *              AmlLength       - AML byte count for this method
    584  *              WalkState       - Current state
    585  *
    586  * RETURN:      Status
    587  *
    588  * DESCRIPTION: Create a new method object
    589  *
    590  ******************************************************************************/
    591 
    592 ACPI_STATUS
    593 AcpiExCreateMethod (
    594     UINT8                   *AmlStart,
    595     UINT32                  AmlLength,
    596     ACPI_WALK_STATE         *WalkState)
    597 {
    598     ACPI_OPERAND_OBJECT     **Operand = &WalkState->Operands[0];
    599     ACPI_OPERAND_OBJECT     *ObjDesc;
    600     ACPI_STATUS             Status;
    601     UINT8                   MethodFlags;
    602 
    603 
    604     ACPI_FUNCTION_TRACE_PTR (ExCreateMethod, WalkState);
    605 
    606 
    607     /* Create a new method object */
    608 
    609     ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_METHOD);
    610     if (!ObjDesc)
    611     {
    612        Status = AE_NO_MEMORY;
    613        goto Exit;
    614     }
    615 
    616     /* Save the method's AML pointer and length  */
    617 
    618     ObjDesc->Method.AmlStart = AmlStart;
    619     ObjDesc->Method.AmlLength = AmlLength;
    620     ObjDesc->Method.Node = Operand[0];
    621 
    622     /*
    623      * Disassemble the method flags. Split off the ArgCount, Serialized
    624      * flag, and SyncLevel for efficiency.
    625      */
    626     MethodFlags = (UINT8) Operand[1]->Integer.Value;
    627     ObjDesc->Method.ParamCount = (UINT8)
    628         (MethodFlags & AML_METHOD_ARG_COUNT);
    629 
    630     /*
    631      * Get the SyncLevel. If method is serialized, a mutex will be
    632      * created for this method when it is parsed.
    633      */
    634     if (MethodFlags & AML_METHOD_SERIALIZED)
    635     {
    636         ObjDesc->Method.InfoFlags = ACPI_METHOD_SERIALIZED;
    637 
    638         /*
    639          * ACPI 1.0: SyncLevel = 0
    640          * ACPI 2.0: SyncLevel = SyncLevel in method declaration
    641          */
    642         ObjDesc->Method.SyncLevel = (UINT8)
    643             ((MethodFlags & AML_METHOD_SYNC_LEVEL) >> 4);
    644     }
    645 
    646     /* Attach the new object to the method Node */
    647 
    648     Status = AcpiNsAttachObject ((ACPI_NAMESPACE_NODE *) Operand[0],
    649         ObjDesc, ACPI_TYPE_METHOD);
    650 
    651     /* Remove local reference to the object */
    652 
    653     AcpiUtRemoveReference (ObjDesc);
    654 
    655 Exit:
    656     /* Remove a reference to the operand */
    657 
    658     AcpiUtRemoveReference (Operand[1]);
    659     return_ACPI_STATUS (Status);
    660 }
    661