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      1 /*******************************************************************************
      2  *
      3  * Module Name: dmresrc.c - Resource Descriptor disassembly
      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  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
     87  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
     88  * PARTICULAR PURPOSE.
     89  *
     90  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
     91  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
     92  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
     93  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
     94  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
     95  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
     96  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
     97  * LIMITED REMEDY.
     98  *
     99  * 4.3. Licensee shall not export, either directly or indirectly, any of this
    100  * software or system incorporating such software without first obtaining any
    101  * required license or other approval from the U. S. Department of Commerce or
    102  * any other agency or department of the United States Government. In the
    103  * event Licensee exports any such software from the United States or
    104  * re-exports any such software from a foreign destination, Licensee shall
    105  * ensure that the distribution and export/re-export of the software is in
    106  * compliance with all laws, regulations, orders, or other restrictions of the
    107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
    108  * any of its subsidiaries will export/re-export any technical data, process,
    109  * software, or service, directly or indirectly, to any country for which the
    110  * United States government or any agency thereof requires an export license,
    111  * other governmental approval, or letter of assurance, without first obtaining
    112  * such license, approval or letter.
    113  *
    114  *****************************************************************************
    115  *
    116  * Alternatively, you may choose to be licensed under the terms of the
    117  * following license:
    118  *
    119  * Redistribution and use in source and binary forms, with or without
    120  * modification, are permitted provided that the following conditions
    121  * are met:
    122  * 1. Redistributions of source code must retain the above copyright
    123  *    notice, this list of conditions, and the following disclaimer,
    124  *    without modification.
    125  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
    126  *    substantially similar to the "NO WARRANTY" disclaimer below
    127  *    ("Disclaimer") and any redistribution must be conditioned upon
    128  *    including a substantially similar Disclaimer requirement for further
    129  *    binary redistribution.
    130  * 3. Neither the names of the above-listed copyright holders nor the names
    131  *    of any contributors may be used to endorse or promote products derived
    132  *    from this software without specific prior written permission.
    133  *
    134  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
    135  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
    136  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
    137  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
    138  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
    139  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
    140  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
    141  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
    142  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    143  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
    144  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
    145  *
    146  * Alternatively, you may choose to be licensed under the terms of the
    147  * GNU General Public License ("GPL") version 2 as published by the Free
    148  * Software Foundation.
    149  *
    150  *****************************************************************************/
    151 
    152 #include "acpi.h"
    153 #include "accommon.h"
    154 #include "amlcode.h"
    155 #include "acdisasm.h"
    156 
    157 
    158 #define _COMPONENT          ACPI_CA_DEBUGGER
    159         ACPI_MODULE_NAME    ("dbresrc")
    160 
    161 
    162 /* Dispatch tables for Resource disassembly functions */
    163 
    164 static ACPI_RESOURCE_HANDLER    AcpiGbl_DmResourceDispatch [] =
    165 {
    166     /* Small descriptors */
    167 
    168     NULL,                           /* 0x00, Reserved */
    169     NULL,                           /* 0x01, Reserved */
    170     NULL,                           /* 0x02, Reserved */
    171     NULL,                           /* 0x03, Reserved */
    172     AcpiDmIrqDescriptor,            /* 0x04, ACPI_RESOURCE_NAME_IRQ_FORMAT */
    173     AcpiDmDmaDescriptor,            /* 0x05, ACPI_RESOURCE_NAME_DMA_FORMAT */
    174     AcpiDmStartDependentDescriptor, /* 0x06, ACPI_RESOURCE_NAME_START_DEPENDENT */
    175     AcpiDmEndDependentDescriptor,   /* 0x07, ACPI_RESOURCE_NAME_END_DEPENDENT */
    176     AcpiDmIoDescriptor,             /* 0x08, ACPI_RESOURCE_NAME_IO_PORT */
    177     AcpiDmFixedIoDescriptor,        /* 0x09, ACPI_RESOURCE_NAME_FIXED_IO_PORT */
    178     AcpiDmFixedDmaDescriptor,       /* 0x0A, ACPI_RESOURCE_NAME_FIXED_DMA */
    179     NULL,                           /* 0x0B, Reserved */
    180     NULL,                           /* 0x0C, Reserved */
    181     NULL,                           /* 0x0D, Reserved */
    182     AcpiDmVendorSmallDescriptor,    /* 0x0E, ACPI_RESOURCE_NAME_SMALL_VENDOR */
    183     NULL,                           /* 0x0F, ACPI_RESOURCE_NAME_END_TAG (not used) */
    184 
    185     /* Large descriptors */
    186 
    187     NULL,                           /* 0x00, Reserved */
    188     AcpiDmMemory24Descriptor,       /* 0x01, ACPI_RESOURCE_NAME_MEMORY_24 */
    189     AcpiDmGenericRegisterDescriptor,/* 0x02, ACPI_RESOURCE_NAME_GENERIC_REGISTER */
    190     NULL,                           /* 0x03, Reserved */
    191     AcpiDmVendorLargeDescriptor,    /* 0x04, ACPI_RESOURCE_NAME_LARGE_VENDOR */
    192     AcpiDmMemory32Descriptor,       /* 0x05, ACPI_RESOURCE_NAME_MEMORY_32 */
    193     AcpiDmFixedMemory32Descriptor,  /* 0x06, ACPI_RESOURCE_NAME_FIXED_MEMORY_32 */
    194     AcpiDmDwordDescriptor,          /* 0x07, ACPI_RESOURCE_NAME_DWORD_ADDRESS_SPACE */
    195     AcpiDmWordDescriptor,           /* 0x08, ACPI_RESOURCE_NAME_WORD_ADDRESS_SPACE */
    196     AcpiDmInterruptDescriptor,      /* 0x09, ACPI_RESOURCE_NAME_EXTENDED_XRUPT */
    197     AcpiDmQwordDescriptor,          /* 0x0A, ACPI_RESOURCE_NAME_QWORD_ADDRESS_SPACE */
    198     AcpiDmExtendedDescriptor,       /* 0x0B, ACPI_RESOURCE_NAME_EXTENDED_ADDRESS_SPACE */
    199     AcpiDmGpioDescriptor,           /* 0x0C, ACPI_RESOURCE_NAME_GPIO */
    200     AcpiDmPinFunctionDescriptor,    /* 0x0D, ACPI_RESOURCE_NAME_PIN_FUNCTION */
    201     AcpiDmSerialBusDescriptor,      /* 0x0E, ACPI_RESOURCE_NAME_SERIAL_BUS */
    202     AcpiDmPinConfigDescriptor,      /* 0x0F, ACPI_RESOURCE_NAME_PIN_CONFIG */
    203     AcpiDmPinGroupDescriptor,       /* 0x10, ACPI_RESOURCE_NAME_PIN_GROUP */
    204     AcpiDmPinGroupFunctionDescriptor, /* 0x11, ACPI_RESOURCE_NAME_PIN_GROUP_FUNCTION */
    205     AcpiDmPinGroupConfigDescriptor, /* 0x12, ACPI_RESOURCE_NAME_PIN_GROUP_CONFIG */
    206     AcpiDmClockInputDescriptor,     /* 0x13, ACPI_RESOURCE_NAME_CLOCK_INPUT */
    207 };
    208 
    209 
    210 /* Only used for single-threaded applications */
    211 /* TBD: remove when name is passed as parameter to the dump functions */
    212 
    213 static UINT32               ResourceName;
    214 
    215 
    216 /*******************************************************************************
    217  *
    218  * FUNCTION:    AcpiDmDescriptorName
    219  *
    220  * PARAMETERS:  None
    221  *
    222  * RETURN:      None
    223  *
    224  * DESCRIPTION: Emit a name for the descriptor if one is present (indicated
    225  *              by the name being changed from the default name.) A name is only
    226  *              emitted if a reference to the descriptor has been made somewhere
    227  *              in the original ASL code.
    228  *
    229  ******************************************************************************/
    230 
    231 void
    232 AcpiDmDescriptorName (
    233     void)
    234 {
    235 
    236     if (ResourceName == ACPI_DEFAULT_RESNAME)
    237     {
    238         return;
    239     }
    240 
    241     AcpiOsPrintf ("%4.4s", (char *) &ResourceName);
    242 }
    243 
    244 
    245 /*******************************************************************************
    246  *
    247  * FUNCTION:    AcpiDmDumpInteger*
    248  *
    249  * PARAMETERS:  Value               - Value to emit
    250  *              Name                - Associated name (emitted as a comment)
    251  *
    252  * RETURN:      None
    253  *
    254  * DESCRIPTION: Integer output helper functions
    255  *
    256  ******************************************************************************/
    257 
    258 void
    259 AcpiDmDumpInteger8 (
    260     UINT8                   Value,
    261     const char              *Name)
    262 {
    263     AcpiOsPrintf ("0x%2.2X,               // %s\n", Value, Name);
    264 }
    265 
    266 void
    267 AcpiDmDumpInteger16 (
    268     UINT16                  Value,
    269     const char              *Name)
    270 {
    271     AcpiOsPrintf ("0x%4.4X,             // %s\n", Value, Name);
    272 }
    273 
    274 void
    275 AcpiDmDumpInteger32 (
    276     UINT32                  Value,
    277     const char              *Name)
    278 {
    279     AcpiOsPrintf ("0x%8.8X,         // %s\n", Value, Name);
    280 }
    281 
    282 void
    283 AcpiDmDumpInteger64 (
    284     UINT64                  Value,
    285     const char              *Name)
    286 {
    287     AcpiOsPrintf ("0x%8.8X%8.8X, // %s\n", ACPI_FORMAT_UINT64 (Value), Name);
    288 }
    289 
    290 
    291 /*******************************************************************************
    292  *
    293  * FUNCTION:    AcpiDmBitList
    294  *
    295  * PARAMETERS:  Mask            - 16-bit value corresponding to 16 interrupt
    296  *                                or DMA values
    297  *
    298  * RETURN:      None
    299  *
    300  * DESCRIPTION: Dump a bit mask as a list of individual interrupt/DMA levels.
    301  *
    302  ******************************************************************************/
    303 
    304 void
    305 AcpiDmBitList (
    306     UINT16                  Mask)
    307 {
    308     UINT32                  i;
    309     BOOLEAN                 Previous = FALSE;
    310 
    311 
    312     /* Open the initializer list */
    313 
    314     AcpiOsPrintf ("{");
    315 
    316     /* Examine each bit */
    317 
    318     for (i = 0; i < 16; i++)
    319     {
    320         /* Only interested in bits that are set to 1 */
    321 
    322         if (Mask & 1)
    323         {
    324             if (Previous)
    325             {
    326                 AcpiOsPrintf (",");
    327             }
    328 
    329             Previous = TRUE;
    330             AcpiOsPrintf ("%u", i);
    331         }
    332 
    333         Mask >>= 1;
    334     }
    335 
    336     /* Close list */
    337 
    338     AcpiOsPrintf ("}\n");
    339 }
    340 
    341 
    342 /*******************************************************************************
    343  *
    344  * FUNCTION:    AcpiDmResourceTemplate
    345  *
    346  * PARAMETERS:  Info            - Current parse tree walk info
    347  *              ByteData        - Pointer to the byte list data
    348  *              ByteCount       - Length of the byte list
    349  *
    350  * RETURN:      None
    351  *
    352  * DESCRIPTION: Dump the contents of a Resource Template containing a set of
    353  *              Resource Descriptors.
    354  *
    355  ******************************************************************************/
    356 
    357 void
    358 AcpiDmResourceTemplate (
    359     ACPI_OP_WALK_INFO       *Info,
    360     ACPI_PARSE_OBJECT       *Op,
    361     UINT8                   *ByteData,
    362     UINT32                  ByteCount)
    363 {
    364     ACPI_STATUS             Status;
    365     UINT32                  CurrentByteOffset;
    366     UINT8                   ResourceType;
    367     UINT32                  ResourceLength;
    368     void                    *Aml;
    369     UINT32                  Level;
    370     BOOLEAN                 DependentFns = FALSE;
    371     UINT8                   ResourceIndex;
    372     ACPI_NAMESPACE_NODE     *Node;
    373 
    374 
    375     if (Op->Asl.AmlOpcode != AML_FIELD_OP)
    376     {
    377         Info->MappingOp = Op;
    378     }
    379 
    380     Level = Info->Level;
    381     ResourceName = ACPI_DEFAULT_RESNAME;
    382     Node = Op->Common.Node;
    383     if (Node)
    384     {
    385         Node = Node->Child;
    386     }
    387 
    388     for (CurrentByteOffset = 0; CurrentByteOffset < ByteCount;)
    389     {
    390         Aml = &ByteData[CurrentByteOffset];
    391 
    392         /* Get the descriptor type and length */
    393 
    394         ResourceType = AcpiUtGetResourceType (Aml);
    395         ResourceLength = AcpiUtGetResourceLength (Aml);
    396 
    397         /* Validate the Resource Type and Resource Length */
    398 
    399         Status = AcpiUtValidateResource (NULL, Aml, &ResourceIndex);
    400         if (ACPI_FAILURE (Status))
    401         {
    402             AcpiOsPrintf (
    403                 "/*** Could not validate Resource, type (%X) %s***/\n",
    404                 ResourceType, AcpiFormatException (Status));
    405             return;
    406         }
    407 
    408         /* Point to next descriptor */
    409 
    410         CurrentByteOffset += AcpiUtGetDescriptorLength (Aml);
    411 
    412         /* Descriptor pre-processing */
    413 
    414         switch (ResourceType)
    415         {
    416         case ACPI_RESOURCE_NAME_START_DEPENDENT:
    417 
    418             /* Finish a previous StartDependentFns */
    419 
    420             if (DependentFns)
    421             {
    422                 Level--;
    423                 AcpiDmIndent (Level);
    424                 AcpiOsPrintf ("}\n");
    425             }
    426             break;
    427 
    428         case ACPI_RESOURCE_NAME_END_DEPENDENT:
    429 
    430             Level--;
    431             DependentFns = FALSE;
    432             break;
    433 
    434         case ACPI_RESOURCE_NAME_END_TAG:
    435 
    436             /* Normal exit, the resource list is finished */
    437 
    438             if (DependentFns)
    439             {
    440                 /*
    441                  * Close an open StartDependentDescriptor. This indicates a
    442                  * missing EndDependentDescriptor.
    443                  */
    444                 Level--;
    445 
    446                 /* Go ahead and insert EndDependentFn() */
    447 
    448                 AcpiDmEndDependentDescriptor (Info, Aml, ResourceLength, Level);
    449 
    450                 AcpiDmIndent (Level);
    451                 AcpiOsPrintf (
    452                     "/*** Disassembler: inserted "
    453                     "missing EndDependentFn () ***/\n");
    454             }
    455             return;
    456 
    457         default:
    458 
    459             break;
    460         }
    461 
    462         /* Disassemble the resource structure */
    463 
    464         if (Node)
    465         {
    466             ResourceName = Node->Name.Integer;
    467             Node = Node->Peer;
    468         }
    469 
    470         AcpiGbl_DmResourceDispatch [ResourceIndex] (
    471             Info, Aml, ResourceLength, Level);
    472 
    473         /* Descriptor post-processing */
    474 
    475         if (ResourceType == ACPI_RESOURCE_NAME_START_DEPENDENT)
    476         {
    477             DependentFns = TRUE;
    478             Level++;
    479         }
    480     }
    481 }
    482 
    483 
    484 /*******************************************************************************
    485  *
    486  * FUNCTION:    AcpiDmIsResourceTemplate
    487  *
    488  * PARAMETERS:  WalkState           - Current walk info
    489  *              Op                  - Buffer Op to be examined
    490  *
    491  * RETURN:      Status. AE_OK if valid template
    492  *
    493  * DESCRIPTION: Walk a byte list to determine if it consists of a valid set
    494  *              of resource descriptors. Nothing is output.
    495  *
    496  ******************************************************************************/
    497 
    498 ACPI_STATUS
    499 AcpiDmIsResourceTemplate (
    500     ACPI_WALK_STATE         *WalkState,
    501     ACPI_PARSE_OBJECT       *Op)
    502 {
    503     ACPI_STATUS             Status;
    504     ACPI_PARSE_OBJECT       *NextOp;
    505     UINT8                   *Aml;
    506     UINT8                   *EndAml;
    507     UINT32                  BufferLength;
    508     UINT32                  DeclaredBufferLength;
    509 
    510 
    511     /* This op must be a buffer */
    512 
    513     if (Op->Common.AmlOpcode != AML_BUFFER_OP)
    514     {
    515         return (AE_TYPE);
    516     }
    517 
    518     /*
    519      * Get the declared length of the buffer.
    520      * This is the nn in "Buffer (nn)"
    521      */
    522     NextOp = Op->Common.Value.Arg;
    523     if (!NextOp)
    524     {
    525         AcpiOsPrintf ("NULL byte list in buffer\n");
    526         return (AE_TYPE);
    527     }
    528 
    529     DeclaredBufferLength = NextOp->Common.Value.Size;
    530 
    531     /* Get the length of the raw initialization byte list */
    532 
    533     NextOp = NextOp->Common.Next;
    534     if (!NextOp)
    535     {
    536         return (AE_TYPE);
    537     }
    538 
    539     Aml = NextOp->Named.Data;
    540     BufferLength = NextOp->Common.Value.Size;
    541 
    542     /*
    543      * Any buffer smaller than one byte cannot possibly be a resource
    544      * template. Two bytes could possibly be a "NULL" resource template
    545      * with a lone end tag descriptor (as generated via
    546      * "ResourceTemplate(){}"), but this would be an extremely unusual
    547      * case, as the template would be essentially useless. The disassembler
    548      * therefore does not recognize any two-byte buffer as a resource
    549      * template.
    550      */
    551     if (BufferLength <= 2)
    552     {
    553         return (AE_TYPE);
    554     }
    555 
    556     /*
    557      * Not a template if declared buffer length != actual length of the
    558      * initialization byte list. Because the resource macros will create
    559      * a buffer of the exact required length (buffer length will be equal
    560      * to the actual length).
    561      *
    562      * NOTE (April 2017): Resource templates with this issue have been
    563      * seen in the field. We still don't want to attempt to disassemble
    564      * a buffer like this to a resource template because this output
    565      * would not match the original input buffer (it would be shorter
    566      * than the original when the disassembled code is recompiled).
    567      * Basically, a buffer like this appears to be hand crafted in the
    568      * first place, so just emitting a buffer object instead of a
    569      * resource template more closely resembles the original ASL code.
    570      */
    571     if (DeclaredBufferLength != BufferLength)
    572     {
    573         return (AE_TYPE);
    574     }
    575 
    576     /* Walk the byte list, abort on any invalid descriptor type or length */
    577 
    578     Status = AcpiUtWalkAmlResources (WalkState, Aml, BufferLength,
    579         NULL, ACPI_CAST_INDIRECT_PTR (void, &EndAml));
    580     if (ACPI_FAILURE (Status))
    581     {
    582         return (AE_TYPE);
    583     }
    584 
    585     /*
    586      * For the resource template to be valid, one EndTag must appear
    587      * at the very end of the ByteList, not before. (For proper disassembly
    588      * of a ResourceTemplate, the buffer must not have any extra data after
    589      * the EndTag.)
    590      */
    591     if ((Aml + BufferLength - sizeof (AML_RESOURCE_END_TAG)) != EndAml)
    592     {
    593         return (AE_AML_NO_RESOURCE_END_TAG);
    594     }
    595 
    596     /*
    597      * All resource descriptors are valid, therefore this list appears
    598      * to be a valid resource template
    599      */
    600     return (AE_OK);
    601 }
    602