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  1. /******************************************************************************
  2.  *
  3.  * Module Name: psargs - Parse AML opcode arguments
  4.  *
  5.  *****************************************************************************/
  6.  
  7. /******************************************************************************
  8.  *
  9.  * 1. Copyright Notice
  10.  *
  11.  * Some or all of this work - Copyright (c) 1999 - 2011, 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. #define __PSARGS_C__
  117.  
  118. #include "acpi.h"
  119. #include "accommon.h"
  120. #include "acparser.h"
  121. #include "amlcode.h"
  122. #include "acnamesp.h"
  123. #include "acdispat.h"
  124.  
  125. #define _COMPONENT          ACPI_PARSER
  126.         ACPI_MODULE_NAME    ("psargs")
  127.  
  128. /* Local prototypes */
  129.  
  130. static UINT32
  131. AcpiPsGetNextPackageLength (
  132.     ACPI_PARSE_STATE        *ParserState);
  133.  
  134. static ACPI_PARSE_OBJECT *
  135. AcpiPsGetNextField (
  136.     ACPI_PARSE_STATE        *ParserState);
  137.  
  138.  
  139. /*******************************************************************************
  140.  *
  141.  * FUNCTION:    AcpiPsGetNextPackageLength
  142.  *
  143.  * PARAMETERS:  ParserState         - Current parser state object
  144.  *
  145.  * RETURN:      Decoded package length. On completion, the AML pointer points
  146.  *              past the length byte or bytes.
  147.  *
  148.  * DESCRIPTION: Decode and return a package length field.
  149.  *              Note: Largest package length is 28 bits, from ACPI specification
  150.  *
  151.  ******************************************************************************/
  152.  
  153. static UINT32
  154. AcpiPsGetNextPackageLength (
  155.     ACPI_PARSE_STATE        *ParserState)
  156. {
  157.     UINT8                   *Aml = ParserState->Aml;
  158.     UINT32                  PackageLength = 0;
  159.     UINT32                  ByteCount;
  160.     UINT8                   ByteZeroMask = 0x3F; /* Default [0:5] */
  161.  
  162.  
  163.     ACPI_FUNCTION_TRACE (PsGetNextPackageLength);
  164.  
  165.  
  166.     /*
  167.      * Byte 0 bits [6:7] contain the number of additional bytes
  168.      * used to encode the package length, either 0,1,2, or 3
  169.      */
  170.     ByteCount = (Aml[0] >> 6);
  171.     ParserState->Aml += ((ACPI_SIZE) ByteCount + 1);
  172.  
  173.     /* Get bytes 3, 2, 1 as needed */
  174.  
  175.     while (ByteCount)
  176.     {
  177.         /*
  178.          * Final bit positions for the package length bytes:
  179.          *      Byte3->[20:27]
  180.          *      Byte2->[12:19]
  181.          *      Byte1->[04:11]
  182.          *      Byte0->[00:03]
  183.          */
  184.         PackageLength |= (Aml[ByteCount] << ((ByteCount << 3) - 4));
  185.  
  186.         ByteZeroMask = 0x0F; /* Use bits [0:3] of byte 0 */
  187.         ByteCount--;
  188.     }
  189.  
  190.     /* Byte 0 is a special case, either bits [0:3] or [0:5] are used */
  191.  
  192.     PackageLength |= (Aml[0] & ByteZeroMask);
  193.     return_UINT32 (PackageLength);
  194. }
  195.  
  196.  
  197. /*******************************************************************************
  198.  *
  199.  * FUNCTION:    AcpiPsGetNextPackageEnd
  200.  *
  201.  * PARAMETERS:  ParserState         - Current parser state object
  202.  *
  203.  * RETURN:      Pointer to end-of-package +1
  204.  *
  205.  * DESCRIPTION: Get next package length and return a pointer past the end of
  206.  *              the package.  Consumes the package length field
  207.  *
  208.  ******************************************************************************/
  209.  
  210. UINT8 *
  211. AcpiPsGetNextPackageEnd (
  212.     ACPI_PARSE_STATE        *ParserState)
  213. {
  214.     UINT8                   *Start = ParserState->Aml;
  215.     UINT32                  PackageLength;
  216.  
  217.  
  218.     ACPI_FUNCTION_TRACE (PsGetNextPackageEnd);
  219.  
  220.  
  221.     /* Function below updates ParserState->Aml */
  222.  
  223.     PackageLength = AcpiPsGetNextPackageLength (ParserState);
  224.  
  225.     return_PTR (Start + PackageLength); /* end of package */
  226. }
  227.  
  228.  
  229. /*******************************************************************************
  230.  *
  231.  * FUNCTION:    AcpiPsGetNextNamestring
  232.  *
  233.  * PARAMETERS:  ParserState         - Current parser state object
  234.  *
  235.  * RETURN:      Pointer to the start of the name string (pointer points into
  236.  *              the AML.
  237.  *
  238.  * DESCRIPTION: Get next raw namestring within the AML stream.  Handles all name
  239.  *              prefix characters.  Set parser state to point past the string.
  240.  *              (Name is consumed from the AML.)
  241.  *
  242.  ******************************************************************************/
  243.  
  244. char *
  245. AcpiPsGetNextNamestring (
  246.     ACPI_PARSE_STATE        *ParserState)
  247. {
  248.     UINT8                   *Start = ParserState->Aml;
  249.     UINT8                   *End = ParserState->Aml;
  250.  
  251.  
  252.     ACPI_FUNCTION_TRACE (PsGetNextNamestring);
  253.  
  254.  
  255.     /* Point past any namestring prefix characters (backslash or carat) */
  256.  
  257.     while (AcpiPsIsPrefixChar (*End))
  258.     {
  259.         End++;
  260.     }
  261.  
  262.     /* Decode the path prefix character */
  263.  
  264.     switch (*End)
  265.     {
  266.     case 0:
  267.  
  268.         /* NullName */
  269.  
  270.         if (End == Start)
  271.         {
  272.             Start = NULL;
  273.         }
  274.         End++;
  275.         break;
  276.  
  277.     case AML_DUAL_NAME_PREFIX:
  278.  
  279.         /* Two name segments */
  280.  
  281.         End += 1 + (2 * ACPI_NAME_SIZE);
  282.         break;
  283.  
  284.     case AML_MULTI_NAME_PREFIX_OP:
  285.  
  286.         /* Multiple name segments, 4 chars each, count in next byte */
  287.  
  288.         End += 2 + (*(End + 1) * ACPI_NAME_SIZE);
  289.         break;
  290.  
  291.     default:
  292.  
  293.         /* Single name segment */
  294.  
  295.         End += ACPI_NAME_SIZE;
  296.         break;
  297.     }
  298.  
  299.     ParserState->Aml = End;
  300.     return_PTR ((char *) Start);
  301. }
  302.  
  303.  
  304. /*******************************************************************************
  305.  *
  306.  * FUNCTION:    AcpiPsGetNextNamepath
  307.  *
  308.  * PARAMETERS:  ParserState         - Current parser state object
  309.  *              Arg                 - Where the namepath will be stored
  310.  *              ArgCount            - If the namepath points to a control method
  311.  *                                    the method's argument is returned here.
  312.  *              PossibleMethodCall  - Whether the namepath can possibly be the
  313.  *                                    start of a method call
  314.  *
  315.  * RETURN:      Status
  316.  *
  317.  * DESCRIPTION: Get next name (if method call, return # of required args).
  318.  *              Names are looked up in the internal namespace to determine
  319.  *              if the name represents a control method.  If a method
  320.  *              is found, the number of arguments to the method is returned.
  321.  *              This information is critical for parsing to continue correctly.
  322.  *
  323.  ******************************************************************************/
  324.  
  325. ACPI_STATUS
  326. AcpiPsGetNextNamepath (
  327.     ACPI_WALK_STATE         *WalkState,
  328.     ACPI_PARSE_STATE        *ParserState,
  329.     ACPI_PARSE_OBJECT       *Arg,
  330.     BOOLEAN                 PossibleMethodCall)
  331. {
  332.     ACPI_STATUS             Status;
  333.     char                    *Path;
  334.     ACPI_PARSE_OBJECT       *NameOp;
  335.     ACPI_OPERAND_OBJECT     *MethodDesc;
  336.     ACPI_NAMESPACE_NODE     *Node;
  337.     UINT8                   *Start = ParserState->Aml;
  338.  
  339.  
  340.     ACPI_FUNCTION_TRACE (PsGetNextNamepath);
  341.  
  342.  
  343.     Path = AcpiPsGetNextNamestring (ParserState);
  344.     AcpiPsInitOp (Arg, AML_INT_NAMEPATH_OP);
  345.  
  346.     /* Null path case is allowed, just exit */
  347.  
  348.     if (!Path)
  349.     {
  350.         Arg->Common.Value.Name = Path;
  351.         return_ACPI_STATUS (AE_OK);
  352.     }
  353.  
  354.     /*
  355.      * Lookup the name in the internal namespace, starting with the current
  356.      * scope. We don't want to add anything new to the namespace here,
  357.      * however, so we use MODE_EXECUTE.
  358.      * Allow searching of the parent tree, but don't open a new scope -
  359.      * we just want to lookup the object (must be mode EXECUTE to perform
  360.      * the upsearch)
  361.      */
  362.     Status = AcpiNsLookup (WalkState->ScopeInfo, Path,
  363.                 ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
  364.                 ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE, NULL, &Node);
  365.  
  366.     /*
  367.      * If this name is a control method invocation, we must
  368.      * setup the method call
  369.      */
  370.     if (ACPI_SUCCESS (Status) &&
  371.         PossibleMethodCall &&
  372.         (Node->Type == ACPI_TYPE_METHOD))
  373.     {
  374.         if (WalkState->Opcode == AML_UNLOAD_OP)
  375.         {
  376.             /*
  377.              * AcpiPsGetNextNamestring has increased the AML pointer,
  378.              * so we need to restore the saved AML pointer for method call.
  379.              */
  380.             WalkState->ParserState.Aml = Start;
  381.             WalkState->ArgCount = 1;
  382.             AcpiPsInitOp (Arg, AML_INT_METHODCALL_OP);
  383.             return_ACPI_STATUS (AE_OK);
  384.         }
  385.  
  386.         /* This name is actually a control method invocation */
  387.  
  388.         MethodDesc = AcpiNsGetAttachedObject (Node);
  389.         ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
  390.             "Control Method - %p Desc %p Path=%p\n", Node, MethodDesc, Path));
  391.  
  392.         NameOp = AcpiPsAllocOp (AML_INT_NAMEPATH_OP);
  393.         if (!NameOp)
  394.         {
  395.             return_ACPI_STATUS (AE_NO_MEMORY);
  396.         }
  397.  
  398.         /* Change Arg into a METHOD CALL and attach name to it */
  399.  
  400.         AcpiPsInitOp (Arg, AML_INT_METHODCALL_OP);
  401.         NameOp->Common.Value.Name = Path;
  402.  
  403.         /* Point METHODCALL/NAME to the METHOD Node */
  404.  
  405.         NameOp->Common.Node = Node;
  406.         AcpiPsAppendArg (Arg, NameOp);
  407.  
  408.         if (!MethodDesc)
  409.         {
  410.             ACPI_ERROR ((AE_INFO,
  411.                 "Control Method %p has no attached object",
  412.                 Node));
  413.             return_ACPI_STATUS (AE_AML_INTERNAL);
  414.         }
  415.  
  416.         ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
  417.             "Control Method - %p Args %X\n",
  418.             Node, MethodDesc->Method.ParamCount));
  419.  
  420.         /* Get the number of arguments to expect */
  421.  
  422.         WalkState->ArgCount = MethodDesc->Method.ParamCount;
  423.         return_ACPI_STATUS (AE_OK);
  424.     }
  425.  
  426.     /*
  427.      * Special handling if the name was not found during the lookup -
  428.      * some NotFound cases are allowed
  429.      */
  430.     if (Status == AE_NOT_FOUND)
  431.     {
  432.         /* 1) NotFound is ok during load pass 1/2 (allow forward references) */
  433.  
  434.         if ((WalkState->ParseFlags & ACPI_PARSE_MODE_MASK) !=
  435.                 ACPI_PARSE_EXECUTE)
  436.         {
  437.             Status = AE_OK;
  438.         }
  439.  
  440.         /* 2) NotFound during a CondRefOf(x) is ok by definition */
  441.  
  442.         else if (WalkState->Op->Common.AmlOpcode == AML_COND_REF_OF_OP)
  443.         {
  444.             Status = AE_OK;
  445.         }
  446.  
  447.         /*
  448.          * 3) NotFound while building a Package is ok at this point, we
  449.          * may flag as an error later if slack mode is not enabled.
  450.          * (Some ASL code depends on allowing this behavior)
  451.          */
  452.         else if ((Arg->Common.Parent) &&
  453.             ((Arg->Common.Parent->Common.AmlOpcode == AML_PACKAGE_OP) ||
  454.              (Arg->Common.Parent->Common.AmlOpcode == AML_VAR_PACKAGE_OP)))
  455.         {
  456.             Status = AE_OK;
  457.         }
  458.     }
  459.  
  460.     /* Final exception check (may have been changed from code above) */
  461.  
  462.     if (ACPI_FAILURE (Status))
  463.     {
  464.         ACPI_ERROR_NAMESPACE (Path, Status);
  465.  
  466.         if ((WalkState->ParseFlags & ACPI_PARSE_MODE_MASK) ==
  467.                 ACPI_PARSE_EXECUTE)
  468.         {
  469.             /* Report a control method execution error */
  470.  
  471.             Status = AcpiDsMethodError (Status, WalkState);
  472.         }
  473.     }
  474.  
  475.     /* Save the namepath */
  476.  
  477.     Arg->Common.Value.Name = Path;
  478.     return_ACPI_STATUS (Status);
  479. }
  480.  
  481.  
  482. /*******************************************************************************
  483.  *
  484.  * FUNCTION:    AcpiPsGetNextSimpleArg
  485.  *
  486.  * PARAMETERS:  ParserState         - Current parser state object
  487.  *              ArgType             - The argument type (AML_*_ARG)
  488.  *              Arg                 - Where the argument is returned
  489.  *
  490.  * RETURN:      None
  491.  *
  492.  * DESCRIPTION: Get the next simple argument (constant, string, or namestring)
  493.  *
  494.  ******************************************************************************/
  495.  
  496. void
  497. AcpiPsGetNextSimpleArg (
  498.     ACPI_PARSE_STATE        *ParserState,
  499.     UINT32                  ArgType,
  500.     ACPI_PARSE_OBJECT       *Arg)
  501. {
  502.     UINT32                  Length;
  503.     UINT16                  Opcode;
  504.     UINT8                   *Aml = ParserState->Aml;
  505.  
  506.  
  507.     ACPI_FUNCTION_TRACE_U32 (PsGetNextSimpleArg, ArgType);
  508.  
  509.  
  510.     switch (ArgType)
  511.     {
  512.     case ARGP_BYTEDATA:
  513.  
  514.         /* Get 1 byte from the AML stream */
  515.  
  516.         Opcode = AML_BYTE_OP;
  517.         Arg->Common.Value.Integer = (UINT64) *Aml;
  518.         Length = 1;
  519.         break;
  520.  
  521.  
  522.     case ARGP_WORDDATA:
  523.  
  524.         /* Get 2 bytes from the AML stream */
  525.  
  526.         Opcode = AML_WORD_OP;
  527.         ACPI_MOVE_16_TO_64 (&Arg->Common.Value.Integer, Aml);
  528.         Length = 2;
  529.         break;
  530.  
  531.  
  532.     case ARGP_DWORDDATA:
  533.  
  534.         /* Get 4 bytes from the AML stream */
  535.  
  536.         Opcode = AML_DWORD_OP;
  537.         ACPI_MOVE_32_TO_64 (&Arg->Common.Value.Integer, Aml);
  538.         Length = 4;
  539.         break;
  540.  
  541.  
  542.     case ARGP_QWORDDATA:
  543.  
  544.         /* Get 8 bytes from the AML stream */
  545.  
  546.         Opcode = AML_QWORD_OP;
  547.         ACPI_MOVE_64_TO_64 (&Arg->Common.Value.Integer, Aml);
  548.         Length = 8;
  549.         break;
  550.  
  551.  
  552.     case ARGP_CHARLIST:
  553.  
  554.         /* Get a pointer to the string, point past the string */
  555.  
  556.         Opcode = AML_STRING_OP;
  557.         Arg->Common.Value.String = ACPI_CAST_PTR (char, Aml);
  558.  
  559.         /* Find the null terminator */
  560.  
  561.         Length = 0;
  562.         while (Aml[Length])
  563.         {
  564.             Length++;
  565.         }
  566.         Length++;
  567.         break;
  568.  
  569.  
  570.     case ARGP_NAME:
  571.     case ARGP_NAMESTRING:
  572.  
  573.         AcpiPsInitOp (Arg, AML_INT_NAMEPATH_OP);
  574.         Arg->Common.Value.Name = AcpiPsGetNextNamestring (ParserState);
  575.         return_VOID;
  576.  
  577.  
  578.     default:
  579.  
  580.         ACPI_ERROR ((AE_INFO, "Invalid ArgType 0x%X", ArgType));
  581.         return_VOID;
  582.     }
  583.  
  584.     AcpiPsInitOp (Arg, Opcode);
  585.     ParserState->Aml += Length;
  586.     return_VOID;
  587. }
  588.  
  589.  
  590. /*******************************************************************************
  591.  *
  592.  * FUNCTION:    AcpiPsGetNextField
  593.  *
  594.  * PARAMETERS:  ParserState         - Current parser state object
  595.  *
  596.  * RETURN:      A newly allocated FIELD op
  597.  *
  598.  * DESCRIPTION: Get next field (NamedField, ReservedField, or AccessField)
  599.  *
  600.  ******************************************************************************/
  601.  
  602. static ACPI_PARSE_OBJECT *
  603. AcpiPsGetNextField (
  604.     ACPI_PARSE_STATE        *ParserState)
  605. {
  606.     UINT32                  AmlOffset = (UINT32)
  607.                                 ACPI_PTR_DIFF (ParserState->Aml,
  608.                                                ParserState->AmlStart);
  609.     ACPI_PARSE_OBJECT       *Field;
  610.     UINT16                  Opcode;
  611.     UINT32                  Name;
  612.  
  613.  
  614.     ACPI_FUNCTION_TRACE (PsGetNextField);
  615.  
  616.  
  617.     /* Determine field type */
  618.  
  619.     switch (ACPI_GET8 (ParserState->Aml))
  620.     {
  621.     default:
  622.  
  623.         Opcode = AML_INT_NAMEDFIELD_OP;
  624.         break;
  625.  
  626.     case 0x00:
  627.  
  628.         Opcode = AML_INT_RESERVEDFIELD_OP;
  629.         ParserState->Aml++;
  630.         break;
  631.  
  632.     case 0x01:
  633.  
  634.         Opcode = AML_INT_ACCESSFIELD_OP;
  635.         ParserState->Aml++;
  636.         break;
  637.     }
  638.  
  639.     /* Allocate a new field op */
  640.  
  641.     Field = AcpiPsAllocOp (Opcode);
  642.     if (!Field)
  643.     {
  644.         return_PTR (NULL);
  645.     }
  646.  
  647.     Field->Common.AmlOffset = AmlOffset;
  648.  
  649.     /* Decode the field type */
  650.  
  651.     switch (Opcode)
  652.     {
  653.     case AML_INT_NAMEDFIELD_OP:
  654.  
  655.         /* Get the 4-character name */
  656.  
  657.         ACPI_MOVE_32_TO_32 (&Name, ParserState->Aml);
  658.         AcpiPsSetName (Field, Name);
  659.         ParserState->Aml += ACPI_NAME_SIZE;
  660.  
  661.         /* Get the length which is encoded as a package length */
  662.  
  663.         Field->Common.Value.Size = AcpiPsGetNextPackageLength (ParserState);
  664.         break;
  665.  
  666.  
  667.     case AML_INT_RESERVEDFIELD_OP:
  668.  
  669.         /* Get the length which is encoded as a package length */
  670.  
  671.         Field->Common.Value.Size = AcpiPsGetNextPackageLength (ParserState);
  672.         break;
  673.  
  674.  
  675.     case AML_INT_ACCESSFIELD_OP:
  676.  
  677.         /*
  678.          * Get AccessType and AccessAttrib and merge into the field Op
  679.          * AccessType is first operand, AccessAttribute is second
  680.          */
  681.         Field->Common.Value.Integer = (((UINT32) ACPI_GET8 (ParserState->Aml) << 8));
  682.         ParserState->Aml++;
  683.         Field->Common.Value.Integer |= ACPI_GET8 (ParserState->Aml);
  684.         ParserState->Aml++;
  685.         break;
  686.  
  687.     default:
  688.  
  689.         /* Opcode was set in previous switch */
  690.         break;
  691.     }
  692.  
  693.     return_PTR (Field);
  694. }
  695.  
  696.  
  697. /*******************************************************************************
  698.  *
  699.  * FUNCTION:    AcpiPsGetNextArg
  700.  *
  701.  * PARAMETERS:  WalkState           - Current state
  702.  *              ParserState         - Current parser state object
  703.  *              ArgType             - The argument type (AML_*_ARG)
  704.  *              ReturnArg           - Where the next arg is returned
  705.  *
  706.  * RETURN:      Status, and an op object containing the next argument.
  707.  *
  708.  * DESCRIPTION: Get next argument (including complex list arguments that require
  709.  *              pushing the parser stack)
  710.  *
  711.  ******************************************************************************/
  712.  
  713. ACPI_STATUS
  714. AcpiPsGetNextArg (
  715.     ACPI_WALK_STATE         *WalkState,
  716.     ACPI_PARSE_STATE        *ParserState,
  717.     UINT32                  ArgType,
  718.     ACPI_PARSE_OBJECT       **ReturnArg)
  719. {
  720.     ACPI_PARSE_OBJECT       *Arg = NULL;
  721.     ACPI_PARSE_OBJECT       *Prev = NULL;
  722.     ACPI_PARSE_OBJECT       *Field;
  723.     UINT32                  Subop;
  724.     ACPI_STATUS             Status = AE_OK;
  725.  
  726.  
  727.     ACPI_FUNCTION_TRACE_PTR (PsGetNextArg, ParserState);
  728.  
  729.  
  730.     switch (ArgType)
  731.     {
  732.     case ARGP_BYTEDATA:
  733.     case ARGP_WORDDATA:
  734.     case ARGP_DWORDDATA:
  735.     case ARGP_CHARLIST:
  736.     case ARGP_NAME:
  737.     case ARGP_NAMESTRING:
  738.  
  739.         /* Constants, strings, and namestrings are all the same size */
  740.  
  741.         Arg = AcpiPsAllocOp (AML_BYTE_OP);
  742.         if (!Arg)
  743.         {
  744.             return_ACPI_STATUS (AE_NO_MEMORY);
  745.         }
  746.         AcpiPsGetNextSimpleArg (ParserState, ArgType, Arg);
  747.         break;
  748.  
  749.  
  750.     case ARGP_PKGLENGTH:
  751.  
  752.         /* Package length, nothing returned */
  753.  
  754.         ParserState->PkgEnd = AcpiPsGetNextPackageEnd (ParserState);
  755.         break;
  756.  
  757.  
  758.     case ARGP_FIELDLIST:
  759.  
  760.         if (ParserState->Aml < ParserState->PkgEnd)
  761.         {
  762.             /* Non-empty list */
  763.  
  764.             while (ParserState->Aml < ParserState->PkgEnd)
  765.             {
  766.                 Field = AcpiPsGetNextField (ParserState);
  767.                 if (!Field)
  768.                 {
  769.                     return_ACPI_STATUS (AE_NO_MEMORY);
  770.                 }
  771.  
  772.                 if (Prev)
  773.                 {
  774.                     Prev->Common.Next = Field;
  775.                 }
  776.                 else
  777.                 {
  778.                     Arg = Field;
  779.                 }
  780.                 Prev = Field;
  781.             }
  782.  
  783.             /* Skip to End of byte data */
  784.  
  785.             ParserState->Aml = ParserState->PkgEnd;
  786.         }
  787.         break;
  788.  
  789.  
  790.     case ARGP_BYTELIST:
  791.  
  792.         if (ParserState->Aml < ParserState->PkgEnd)
  793.         {
  794.             /* Non-empty list */
  795.  
  796.             Arg = AcpiPsAllocOp (AML_INT_BYTELIST_OP);
  797.             if (!Arg)
  798.             {
  799.                 return_ACPI_STATUS (AE_NO_MEMORY);
  800.             }
  801.  
  802.             /* Fill in bytelist data */
  803.  
  804.             Arg->Common.Value.Size = (UINT32)
  805.                 ACPI_PTR_DIFF (ParserState->PkgEnd, ParserState->Aml);
  806.             Arg->Named.Data = ParserState->Aml;
  807.  
  808.             /* Skip to End of byte data */
  809.  
  810.             ParserState->Aml = ParserState->PkgEnd;
  811.         }
  812.         break;
  813.  
  814.  
  815.     case ARGP_TARGET:
  816.     case ARGP_SUPERNAME:
  817.     case ARGP_SIMPLENAME:
  818.  
  819.         Subop = AcpiPsPeekOpcode (ParserState);
  820.         if (Subop == 0                  ||
  821.             AcpiPsIsLeadingChar (Subop) ||
  822.             AcpiPsIsPrefixChar (Subop))
  823.         {
  824.             /* NullName or NameString */
  825.  
  826.             Arg = AcpiPsAllocOp (AML_INT_NAMEPATH_OP);
  827.             if (!Arg)
  828.             {
  829.                 return_ACPI_STATUS (AE_NO_MEMORY);
  830.             }
  831.  
  832.             /* To support SuperName arg of Unload */
  833.  
  834.             if (WalkState->Opcode == AML_UNLOAD_OP)
  835.             {
  836.                 Status = AcpiPsGetNextNamepath (WalkState, ParserState, Arg, 1);
  837.  
  838.                 /*
  839.                  * If the SuperName arg of Unload is a method call,
  840.                  * we have restored the AML pointer, just free this Arg
  841.                  */
  842.                 if (Arg->Common.AmlOpcode == AML_INT_METHODCALL_OP)
  843.                 {
  844.                     AcpiPsFreeOp (Arg);
  845.                     Arg = NULL;
  846.                 }
  847.             }
  848.             else
  849.             {
  850.                 Status = AcpiPsGetNextNamepath (WalkState, ParserState, Arg, 0);
  851.             }
  852.         }
  853.         else
  854.         {
  855.             /* Single complex argument, nothing returned */
  856.  
  857.             WalkState->ArgCount = 1;
  858.         }
  859.         break;
  860.  
  861.  
  862.     case ARGP_DATAOBJ:
  863.     case ARGP_TERMARG:
  864.  
  865.         /* Single complex argument, nothing returned */
  866.  
  867.         WalkState->ArgCount = 1;
  868.         break;
  869.  
  870.  
  871.     case ARGP_DATAOBJLIST:
  872.     case ARGP_TERMLIST:
  873.     case ARGP_OBJLIST:
  874.  
  875.         if (ParserState->Aml < ParserState->PkgEnd)
  876.         {
  877.             /* Non-empty list of variable arguments, nothing returned */
  878.  
  879.             WalkState->ArgCount = ACPI_VAR_ARGS;
  880.         }
  881.         break;
  882.  
  883.  
  884.     default:
  885.  
  886.         ACPI_ERROR ((AE_INFO, "Invalid ArgType: 0x%X", ArgType));
  887.         Status = AE_AML_OPERAND_TYPE;
  888.         break;
  889.     }
  890.  
  891.     *ReturnArg = Arg;
  892.     return_ACPI_STATUS (Status);
  893. }
  894.