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dmbuffer.c revision 1.1.1.3
      1 /*******************************************************************************
      2  *
      3  * Module Name: dmbuffer - AML disassembler, buffer and string support
      4  *
      5  ******************************************************************************/
      6 
      7 /*
      8  * Copyright (C) 2000 - 2013, Intel Corp.
      9  * All rights reserved.
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions, and the following disclaimer,
     16  *    without modification.
     17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
     18  *    substantially similar to the "NO WARRANTY" disclaimer below
     19  *    ("Disclaimer") and any redistribution must be conditioned upon
     20  *    including a substantially similar Disclaimer requirement for further
     21  *    binary redistribution.
     22  * 3. Neither the names of the above-listed copyright holders nor the names
     23  *    of any contributors may be used to endorse or promote products derived
     24  *    from this software without specific prior written permission.
     25  *
     26  * Alternatively, this software may be distributed under the terms of the
     27  * GNU General Public License ("GPL") version 2 as published by the Free
     28  * Software Foundation.
     29  *
     30  * NO WARRANTY
     31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
     34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
     39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
     40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     41  * POSSIBILITY OF SUCH DAMAGES.
     42  */
     43 
     44 
     45 #include "acpi.h"
     46 #include "accommon.h"
     47 #include "acdisasm.h"
     48 #include "acparser.h"
     49 #include "amlcode.h"
     50 
     51 
     52 #ifdef ACPI_DISASSEMBLER
     53 
     54 #define _COMPONENT          ACPI_CA_DEBUGGER
     55         ACPI_MODULE_NAME    ("dmbuffer")
     56 
     57 /* Local prototypes */
     58 
     59 static void
     60 AcpiDmUnicode (
     61     ACPI_PARSE_OBJECT       *Op);
     62 
     63 static void
     64 AcpiDmIsEisaIdElement (
     65     ACPI_PARSE_OBJECT       *Op);
     66 
     67 static void
     68 AcpiDmPldBuffer (
     69     UINT32                  Level,
     70     UINT8                   *ByteData,
     71     UINT32                  ByteCount);
     72 
     73 
     74 /*******************************************************************************
     75  *
     76  * FUNCTION:    AcpiDmDisasmByteList
     77  *
     78  * PARAMETERS:  Level               - Current source code indentation level
     79  *              ByteData            - Pointer to the byte list
     80  *              ByteCount           - Length of the byte list
     81  *
     82  * RETURN:      None
     83  *
     84  * DESCRIPTION: Dump an AML "ByteList" in Hex format. 8 bytes per line, prefixed
     85  *              with the hex buffer offset.
     86  *
     87  ******************************************************************************/
     88 
     89 void
     90 AcpiDmDisasmByteList (
     91     UINT32                  Level,
     92     UINT8                   *ByteData,
     93     UINT32                  ByteCount)
     94 {
     95     UINT32                  i;
     96 
     97 
     98     if (!ByteCount)
     99     {
    100         return;
    101     }
    102 
    103     /* Dump the byte list */
    104 
    105     for (i = 0; i < ByteCount; i++)
    106     {
    107         /* New line every 8 bytes */
    108 
    109         if (((i % 8) == 0) && (i < ByteCount))
    110         {
    111             if (i > 0)
    112             {
    113                 AcpiOsPrintf ("\n");
    114             }
    115 
    116             AcpiDmIndent (Level);
    117             if (ByteCount > 8)
    118             {
    119                 AcpiOsPrintf ("/* %04X */  ", i);
    120             }
    121         }
    122 
    123         AcpiOsPrintf (" 0x%2.2X", (UINT32) ByteData[i]);
    124 
    125         /* Add comma if there are more bytes to display */
    126 
    127         if (i < (ByteCount -1))
    128         {
    129             AcpiOsPrintf (",");
    130         }
    131     }
    132 
    133     if (Level)
    134     {
    135         AcpiOsPrintf ("\n");
    136     }
    137 }
    138 
    139 
    140 /*******************************************************************************
    141  *
    142  * FUNCTION:    AcpiDmByteList
    143  *
    144  * PARAMETERS:  Info            - Parse tree walk info
    145  *              Op              - Byte list op
    146  *
    147  * RETURN:      None
    148  *
    149  * DESCRIPTION: Dump a buffer byte list, handling the various types of buffers.
    150  *              Buffer type must be already set in the Op DisasmOpcode.
    151  *
    152  ******************************************************************************/
    153 
    154 void
    155 AcpiDmByteList (
    156     ACPI_OP_WALK_INFO       *Info,
    157     ACPI_PARSE_OBJECT       *Op)
    158 {
    159     UINT8                   *ByteData;
    160     UINT32                  ByteCount;
    161 
    162 
    163     ByteData = Op->Named.Data;
    164     ByteCount = (UINT32) Op->Common.Value.Integer;
    165 
    166     /*
    167      * The byte list belongs to a buffer, and can be produced by either
    168      * a ResourceTemplate, Unicode, quoted string, or a plain byte list.
    169      */
    170     switch (Op->Common.Parent->Common.DisasmOpcode)
    171     {
    172     case ACPI_DASM_RESOURCE:
    173 
    174         AcpiDmResourceTemplate (Info, Op->Common.Parent, ByteData, ByteCount);
    175         break;
    176 
    177     case ACPI_DASM_STRING:
    178 
    179         AcpiDmIndent (Info->Level);
    180         AcpiUtPrintString ((char *) ByteData, ACPI_UINT16_MAX);
    181         AcpiOsPrintf ("\n");
    182         break;
    183 
    184     case ACPI_DASM_UNICODE:
    185 
    186         AcpiDmUnicode (Op);
    187         break;
    188 
    189     case ACPI_DASM_PLD_METHOD:
    190 
    191         AcpiDmDisasmByteList (Info->Level, ByteData, ByteCount);
    192         AcpiDmPldBuffer (Info->Level, ByteData, ByteCount);
    193         break;
    194 
    195     case ACPI_DASM_BUFFER:
    196     default:
    197         /*
    198          * Not a resource, string, or unicode string.
    199          * Just dump the buffer
    200          */
    201         AcpiDmDisasmByteList (Info->Level, ByteData, ByteCount);
    202         break;
    203     }
    204 }
    205 
    206 
    207 /*******************************************************************************
    208  *
    209  * FUNCTION:    AcpiDmIsUnicodeBuffer
    210  *
    211  * PARAMETERS:  Op              - Buffer Object to be examined
    212  *
    213  * RETURN:      TRUE if buffer contains a UNICODE string
    214  *
    215  * DESCRIPTION: Determine if a buffer Op contains a Unicode string
    216  *
    217  ******************************************************************************/
    218 
    219 BOOLEAN
    220 AcpiDmIsUnicodeBuffer (
    221     ACPI_PARSE_OBJECT       *Op)
    222 {
    223     UINT8                   *ByteData;
    224     UINT32                  ByteCount;
    225     UINT32                  WordCount;
    226     ACPI_PARSE_OBJECT       *SizeOp;
    227     ACPI_PARSE_OBJECT       *NextOp;
    228     UINT32                  i;
    229 
    230 
    231     /* Buffer size is the buffer argument */
    232 
    233     SizeOp = Op->Common.Value.Arg;
    234 
    235     /* Next, the initializer byte list to examine */
    236 
    237     NextOp = SizeOp->Common.Next;
    238     if (!NextOp)
    239     {
    240         return (FALSE);
    241     }
    242 
    243     /* Extract the byte list info */
    244 
    245     ByteData = NextOp->Named.Data;
    246     ByteCount = (UINT32) NextOp->Common.Value.Integer;
    247     WordCount = ACPI_DIV_2 (ByteCount);
    248 
    249     /*
    250      * Unicode string must have an even number of bytes and last
    251      * word must be zero
    252      */
    253     if ((!ByteCount)     ||
    254          (ByteCount < 4) ||
    255          (ByteCount & 1) ||
    256         ((UINT16 *) (void *) ByteData)[WordCount - 1] != 0)
    257     {
    258         return (FALSE);
    259     }
    260 
    261     /* For each word, 1st byte must be ascii, 2nd byte must be zero */
    262 
    263     for (i = 0; i < (ByteCount - 2); i += 2)
    264     {
    265         if ((!ACPI_IS_PRINT (ByteData[i])) ||
    266             (ByteData[(ACPI_SIZE) i + 1] != 0))
    267         {
    268             return (FALSE);
    269         }
    270     }
    271 
    272     /* Ignore the Size argument in the disassembly of this buffer op */
    273 
    274     SizeOp->Common.DisasmFlags |= ACPI_PARSEOP_IGNORE;
    275     return (TRUE);
    276 }
    277 
    278 
    279 /*******************************************************************************
    280  *
    281  * FUNCTION:    AcpiDmIsStringBuffer
    282  *
    283  * PARAMETERS:  Op              - Buffer Object to be examined
    284  *
    285  * RETURN:      TRUE if buffer contains a ASCII string, FALSE otherwise
    286  *
    287  * DESCRIPTION: Determine if a buffer Op contains a ASCII string
    288  *
    289  ******************************************************************************/
    290 
    291 BOOLEAN
    292 AcpiDmIsStringBuffer (
    293     ACPI_PARSE_OBJECT       *Op)
    294 {
    295     UINT8                   *ByteData;
    296     UINT32                  ByteCount;
    297     ACPI_PARSE_OBJECT       *SizeOp;
    298     ACPI_PARSE_OBJECT       *NextOp;
    299     UINT32                  i;
    300 
    301 
    302     /* Buffer size is the buffer argument */
    303 
    304     SizeOp = Op->Common.Value.Arg;
    305 
    306     /* Next, the initializer byte list to examine */
    307 
    308     NextOp = SizeOp->Common.Next;
    309     if (!NextOp)
    310     {
    311         return (FALSE);
    312     }
    313 
    314     /* Extract the byte list info */
    315 
    316     ByteData = NextOp->Named.Data;
    317     ByteCount = (UINT32) NextOp->Common.Value.Integer;
    318 
    319     /* Last byte must be the null terminator */
    320 
    321     if ((!ByteCount)     ||
    322          (ByteCount < 2) ||
    323          (ByteData[ByteCount-1] != 0))
    324     {
    325         return (FALSE);
    326     }
    327 
    328     for (i = 0; i < (ByteCount - 1); i++)
    329     {
    330         /* TBD: allow some escapes (non-ascii chars).
    331          * they will be handled in the string output routine
    332          */
    333 
    334         if (!ACPI_IS_PRINT (ByteData[i]))
    335         {
    336             return (FALSE);
    337         }
    338     }
    339 
    340     return (TRUE);
    341 }
    342 
    343 
    344 /*******************************************************************************
    345  *
    346  * FUNCTION:    AcpiDmIsPldBuffer
    347  *
    348  * PARAMETERS:  Op                  - Buffer Object to be examined
    349  *
    350  * RETURN:      TRUE if buffer contains a ASCII string, FALSE otherwise
    351  *
    352  * DESCRIPTION: Determine if a buffer Op contains a _PLD structure
    353  *
    354  ******************************************************************************/
    355 
    356 BOOLEAN
    357 AcpiDmIsPldBuffer (
    358     ACPI_PARSE_OBJECT       *Op)
    359 {
    360     ACPI_NAMESPACE_NODE     *Node;
    361     ACPI_PARSE_OBJECT       *ParentOp;
    362 
    363 
    364     ParentOp = Op->Common.Parent;
    365     if (!ParentOp)
    366     {
    367         return (FALSE);
    368     }
    369 
    370     /* Check for form: Name(_PLD, Buffer() {}). Not legal, however */
    371 
    372     if (ParentOp->Common.AmlOpcode == AML_NAME_OP)
    373     {
    374         Node = ParentOp->Common.Node;
    375 
    376         if (ACPI_COMPARE_NAME (Node->Name.Ascii, METHOD_NAME__PLD))
    377         {
    378             return (TRUE);
    379         }
    380 
    381         return (FALSE);
    382     }
    383 
    384     /* Check for proper form: Name(_PLD, Package() {Buffer() {}}) */
    385 
    386     if (ParentOp->Common.AmlOpcode == AML_PACKAGE_OP)
    387     {
    388         ParentOp = ParentOp->Common.Parent;
    389         if (!ParentOp)
    390         {
    391             return (FALSE);
    392         }
    393 
    394         if (ParentOp->Common.AmlOpcode == AML_NAME_OP)
    395         {
    396             Node = ParentOp->Common.Node;
    397 
    398             if (ACPI_COMPARE_NAME (Node->Name.Ascii, METHOD_NAME__PLD))
    399             {
    400                 return (TRUE);
    401             }
    402         }
    403     }
    404 
    405     return (FALSE);
    406 }
    407 
    408 
    409 /*******************************************************************************
    410  *
    411  * FUNCTION:    AcpiDmPldBuffer
    412  *
    413  * PARAMETERS:  Level               - Current source code indentation level
    414  *              ByteData            - Pointer to the byte list
    415  *              ByteCount           - Length of the byte list
    416  *
    417  * RETURN:      None
    418  *
    419  * DESCRIPTION: Dump and format the contents of a _PLD buffer object
    420  *
    421  ******************************************************************************/
    422 
    423 #define ACPI_PLD_OUTPUT08     "%*.s/* %18s : %-6.2X */\n", ACPI_MUL_4 (Level), " "
    424 #define ACPI_PLD_OUTPUT16   "%*.s/* %18s : %-6.4X */\n", ACPI_MUL_4 (Level), " "
    425 #define ACPI_PLD_OUTPUT24   "%*.s/* %18s : %-6.6X */\n", ACPI_MUL_4 (Level), " "
    426 
    427 static void
    428 AcpiDmPldBuffer (
    429     UINT32                  Level,
    430     UINT8                   *ByteData,
    431     UINT32                  ByteCount)
    432 {
    433     ACPI_PLD_INFO           *PldInfo;
    434     ACPI_STATUS             Status;
    435 
    436 
    437     /* Check for valid byte count */
    438 
    439     if (ByteCount < ACPI_PLD_REV1_BUFFER_SIZE)
    440     {
    441         return;
    442     }
    443 
    444     /* Convert _PLD buffer to local _PLD struct */
    445 
    446     Status = AcpiDecodePldBuffer (ByteData, ByteCount, &PldInfo);
    447     if (ACPI_FAILURE (Status))
    448     {
    449         return;
    450     }
    451 
    452     /* First 32-bit dword */
    453 
    454     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "Revision", PldInfo->Revision);
    455     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "IgnoreColor", PldInfo->IgnoreColor);
    456     AcpiOsPrintf (ACPI_PLD_OUTPUT24,"Color", PldInfo->Color);
    457 
    458     /* Second 32-bit dword */
    459 
    460     AcpiOsPrintf (ACPI_PLD_OUTPUT16,"Width", PldInfo->Width);
    461     AcpiOsPrintf (ACPI_PLD_OUTPUT16,"Height", PldInfo->Height);
    462 
    463     /* Third 32-bit dword */
    464 
    465     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "UserVisible", PldInfo->UserVisible);
    466     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "Dock", PldInfo->Dock);
    467     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "Lid", PldInfo->Lid);
    468     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "Panel", PldInfo->Panel);
    469     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "VerticalPosition", PldInfo->VerticalPosition);
    470     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "HorizontalPosition", PldInfo->HorizontalPosition);
    471     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "Shape", PldInfo->Shape);
    472     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "GroupOrientation", PldInfo->GroupOrientation);
    473     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "GroupToken", PldInfo->GroupToken);
    474     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "GroupPosition", PldInfo->GroupPosition);
    475     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "Bay", PldInfo->Bay);
    476 
    477     /* Fourth 32-bit dword */
    478 
    479     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "Ejectable", PldInfo->Ejectable);
    480     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "OspmEjectRequired", PldInfo->OspmEjectRequired);
    481     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "CabinetNumber", PldInfo->CabinetNumber);
    482     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "CardCageNumber", PldInfo->CardCageNumber);
    483     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "Reference", PldInfo->Reference);
    484     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "Rotation", PldInfo->Rotation);
    485     AcpiOsPrintf (ACPI_PLD_OUTPUT08,  "Order", PldInfo->Order);
    486 
    487     /* Fifth 32-bit dword */
    488 
    489     if (ByteCount >= ACPI_PLD_REV1_BUFFER_SIZE)
    490     {
    491         AcpiOsPrintf (ACPI_PLD_OUTPUT16,"VerticalOffset", PldInfo->VerticalOffset);
    492         AcpiOsPrintf (ACPI_PLD_OUTPUT16,"HorizontalOffset", PldInfo->HorizontalOffset);
    493     }
    494 
    495     ACPI_FREE (PldInfo);
    496 }
    497 
    498 
    499 /*******************************************************************************
    500  *
    501  * FUNCTION:    AcpiDmUnicode
    502  *
    503  * PARAMETERS:  Op              - Byte List op containing Unicode string
    504  *
    505  * RETURN:      None
    506  *
    507  * DESCRIPTION: Dump Unicode string as a standard ASCII string. (Remove
    508  *              the extra zero bytes).
    509  *
    510  ******************************************************************************/
    511 
    512 static void
    513 AcpiDmUnicode (
    514     ACPI_PARSE_OBJECT       *Op)
    515 {
    516     UINT16                  *WordData;
    517     UINT32                  WordCount;
    518     UINT32                  i;
    519 
    520 
    521     /* Extract the buffer info as a WORD buffer */
    522 
    523     WordData = ACPI_CAST_PTR (UINT16, Op->Named.Data);
    524     WordCount = ACPI_DIV_2 (((UINT32) Op->Common.Value.Integer));
    525 
    526     /* Write every other byte as an ASCII character */
    527 
    528     AcpiOsPrintf ("\"");
    529     for (i = 0; i < (WordCount - 1); i++)
    530     {
    531         AcpiOsPrintf ("%c", (int) WordData[i]);
    532     }
    533 
    534     AcpiOsPrintf ("\")");
    535 }
    536 
    537 
    538 /*******************************************************************************
    539  *
    540  * FUNCTION:    AcpiDmIsEisaIdElement
    541  *
    542  * PARAMETERS:  Op              - Op to be examined
    543  *
    544  * RETURN:      None
    545  *
    546  * DESCRIPTION: Determine if an Op (argument to _HID or _CID) can be converted
    547  *              to an EISA ID.
    548  *
    549  ******************************************************************************/
    550 
    551 static void
    552 AcpiDmIsEisaIdElement (
    553     ACPI_PARSE_OBJECT       *Op)
    554 {
    555     UINT32                  BigEndianId;
    556     UINT32                  Prefix[3];
    557     UINT32                  i;
    558 
    559 
    560     /* The parameter must be either a word or a dword */
    561 
    562     if ((Op->Common.AmlOpcode != AML_DWORD_OP) &&
    563         (Op->Common.AmlOpcode != AML_WORD_OP))
    564     {
    565         return;
    566     }
    567 
    568     /* Swap from little-endian to big-endian to simplify conversion */
    569 
    570     BigEndianId = AcpiUtDwordByteSwap ((UINT32) Op->Common.Value.Integer);
    571 
    572     /* Create the 3 leading ASCII letters */
    573 
    574     Prefix[0] = ((BigEndianId >> 26) & 0x1F) + 0x40;
    575     Prefix[1] = ((BigEndianId >> 21) & 0x1F) + 0x40;
    576     Prefix[2] = ((BigEndianId >> 16) & 0x1F) + 0x40;
    577 
    578     /* Verify that all 3 are ascii and alpha */
    579 
    580     for (i = 0; i < 3; i++)
    581     {
    582         if (!ACPI_IS_ASCII (Prefix[i]) ||
    583             !ACPI_IS_ALPHA (Prefix[i]))
    584         {
    585             return;
    586         }
    587     }
    588 
    589     /* OK - mark this node as convertable to an EISA ID */
    590 
    591     Op->Common.DisasmOpcode = ACPI_DASM_EISAID;
    592 }
    593 
    594 
    595 /*******************************************************************************
    596  *
    597  * FUNCTION:    AcpiDmIsEisaId
    598  *
    599  * PARAMETERS:  Op              - Op to be examined
    600  *
    601  * RETURN:      None
    602  *
    603  * DESCRIPTION: Determine if a Name() Op can be converted to an EisaId.
    604  *
    605  ******************************************************************************/
    606 
    607 void
    608 AcpiDmIsEisaId (
    609     ACPI_PARSE_OBJECT       *Op)
    610 {
    611     UINT32                  Name;
    612     ACPI_PARSE_OBJECT       *NextOp;
    613 
    614 
    615     /* Get the NameSegment */
    616 
    617     Name = AcpiPsGetName (Op);
    618     if (!Name)
    619     {
    620         return;
    621     }
    622 
    623     NextOp = AcpiPsGetDepthNext (NULL, Op);
    624     if (!NextOp)
    625     {
    626         return;
    627     }
    628 
    629     /* Check for _HID - has one argument */
    630 
    631     if (ACPI_COMPARE_NAME (&Name, METHOD_NAME__HID))
    632     {
    633         AcpiDmIsEisaIdElement (NextOp);
    634         return;
    635     }
    636 
    637     /* Exit if not _CID */
    638 
    639     if (!ACPI_COMPARE_NAME (&Name, METHOD_NAME__CID))
    640     {
    641         return;
    642     }
    643 
    644     /* _CID can contain a single argument or a package */
    645 
    646     if (NextOp->Common.AmlOpcode != AML_PACKAGE_OP)
    647     {
    648         AcpiDmIsEisaIdElement (NextOp);
    649         return;
    650     }
    651 
    652     /* _CID with Package: get the package length */
    653 
    654     NextOp = AcpiPsGetDepthNext (NULL, NextOp);
    655 
    656     /* Don't need to use the length, just walk the peer list */
    657 
    658     NextOp = NextOp->Common.Next;
    659     while (NextOp)
    660     {
    661         AcpiDmIsEisaIdElement (NextOp);
    662         NextOp = NextOp->Common.Next;
    663     }
    664 }
    665 
    666 
    667 /*******************************************************************************
    668  *
    669  * FUNCTION:    AcpiDmEisaId
    670  *
    671  * PARAMETERS:  EncodedId       - Raw encoded EISA ID.
    672  *
    673  * RETURN:      None
    674  *
    675  * DESCRIPTION: Convert an encoded EISAID back to the original ASCII String.
    676  *
    677  ******************************************************************************/
    678 
    679 void
    680 AcpiDmEisaId (
    681     UINT32                  EncodedId)
    682 {
    683     UINT32                  BigEndianId;
    684 
    685 
    686     /* Swap from little-endian to big-endian to simplify conversion */
    687 
    688     BigEndianId = AcpiUtDwordByteSwap (EncodedId);
    689 
    690 
    691     /* Split to form "AAANNNN" string */
    692 
    693     AcpiOsPrintf ("EisaId (\"%c%c%c%4.4X\")",
    694 
    695         /* Three Alpha characters (AAA), 5 bits each */
    696 
    697         (int) ((BigEndianId >> 26) & 0x1F) + 0x40,
    698         (int) ((BigEndianId >> 21) & 0x1F) + 0x40,
    699         (int) ((BigEndianId >> 16) & 0x1F) + 0x40,
    700 
    701         /* Numeric part (NNNN) is simply the lower 16 bits */
    702 
    703         (UINT32) (BigEndianId & 0xFFFF));
    704 }
    705 
    706 #endif
    707