Subversion Repositories Kolibri OS

Rev

Go to most recent revision | Blame | Compare with Previous | Last modification | View Log | Download | RSS feed

  1.  
  2. /******************************************************************************
  3.  *
  4.  * Module Name: exprep - ACPI AML (p-code) execution - field prep utilities
  5.  *
  6.  *****************************************************************************/
  7.  
  8. /******************************************************************************
  9.  *
  10.  * 1. Copyright Notice
  11.  *
  12.  * Some or all of this work - Copyright (c) 1999 - 2010, Intel Corp.
  13.  * All rights reserved.
  14.  *
  15.  * 2. License
  16.  *
  17.  * 2.1. This is your license from Intel Corp. under its intellectual property
  18.  * rights.  You may have additional license terms from the party that provided
  19.  * you this software, covering your right to use that party's intellectual
  20.  * property rights.
  21.  *
  22.  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
  23.  * copy of the source code appearing in this file ("Covered Code") an
  24.  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
  25.  * base code distributed originally by Intel ("Original Intel Code") to copy,
  26.  * make derivatives, distribute, use and display any portion of the Covered
  27.  * Code in any form, with the right to sublicense such rights; and
  28.  *
  29.  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
  30.  * license (with the right to sublicense), under only those claims of Intel
  31.  * patents that are infringed by the Original Intel Code, to make, use, sell,
  32.  * offer to sell, and import the Covered Code and derivative works thereof
  33.  * solely to the minimum extent necessary to exercise the above copyright
  34.  * license, and in no event shall the patent license extend to any additions
  35.  * to or modifications of the Original Intel Code.  No other license or right
  36.  * is granted directly or by implication, estoppel or otherwise;
  37.  *
  38.  * The above copyright and patent license is granted only if the following
  39.  * conditions are met:
  40.  *
  41.  * 3. Conditions
  42.  *
  43.  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
  44.  * Redistribution of source code of any substantial portion of the Covered
  45.  * Code or modification with rights to further distribute source must include
  46.  * the above Copyright Notice, the above License, this list of Conditions,
  47.  * and the following Disclaimer and Export Compliance provision.  In addition,
  48.  * Licensee must cause all Covered Code to which Licensee contributes to
  49.  * contain a file documenting the changes Licensee made to create that Covered
  50.  * Code and the date of any change.  Licensee must include in that file the
  51.  * documentation of any changes made by any predecessor Licensee.  Licensee
  52.  * must include a prominent statement that the modification is derived,
  53.  * directly or indirectly, from Original Intel Code.
  54.  *
  55.  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
  56.  * Redistribution of source code of any substantial portion of the Covered
  57.  * Code or modification without rights to further distribute source must
  58.  * include the following Disclaimer and Export Compliance provision in the
  59.  * documentation and/or other materials provided with distribution.  In
  60.  * addition, Licensee may not authorize further sublicense of source of any
  61.  * portion of the Covered Code, and must include terms to the effect that the
  62.  * license from Licensee to its licensee is limited to the intellectual
  63.  * property embodied in the software Licensee provides to its licensee, and
  64.  * not to intellectual property embodied in modifications its licensee may
  65.  * make.
  66.  *
  67.  * 3.3. Redistribution of Executable. Redistribution in executable form of any
  68.  * substantial portion of the Covered Code or modification must reproduce the
  69.  * above Copyright Notice, and the following Disclaimer and Export Compliance
  70.  * provision in the documentation and/or other materials provided with the
  71.  * distribution.
  72.  *
  73.  * 3.4. Intel retains all right, title, and interest in and to the Original
  74.  * Intel Code.
  75.  *
  76.  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
  77.  * Intel shall be used in advertising or otherwise to promote the sale, use or
  78.  * other dealings in products derived from or relating to the Covered Code
  79.  * without prior written authorization from Intel.
  80.  *
  81.  * 4. Disclaimer and Export Compliance
  82.  *
  83.  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
  84.  * HERE.  ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
  85.  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT,  ASSISTANCE,
  86.  * INSTALLATION, TRAINING OR OTHER SERVICES.  INTEL WILL NOT PROVIDE ANY
  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. #define __EXPREP_C__
  118.  
  119. #include "acpi.h"
  120. #include "accommon.h"
  121. #include "acinterp.h"
  122. #include "amlcode.h"
  123. #include "acnamesp.h"
  124.  
  125.  
  126. #define _COMPONENT          ACPI_EXECUTER
  127.         ACPI_MODULE_NAME    ("exprep")
  128.  
  129. /* Local prototypes */
  130.  
  131. static UINT32
  132. AcpiExDecodeFieldAccess (
  133.     ACPI_OPERAND_OBJECT     *ObjDesc,
  134.     UINT8                   FieldFlags,
  135.     UINT32                  *ReturnByteAlignment);
  136.  
  137.  
  138. #ifdef ACPI_UNDER_DEVELOPMENT
  139.  
  140. static UINT32
  141. AcpiExGenerateAccess (
  142.     UINT32                  FieldBitOffset,
  143.     UINT32                  FieldBitLength,
  144.     UINT32                  RegionLength);
  145.  
  146. /*******************************************************************************
  147.  *
  148.  * FUNCTION:    AcpiExGenerateAccess
  149.  *
  150.  * PARAMETERS:  FieldBitOffset      - Start of field within parent region/buffer
  151.  *              FieldBitLength      - Length of field in bits
  152.  *              RegionLength        - Length of parent in bytes
  153.  *
  154.  * RETURN:      Field granularity (8, 16, 32 or 64) and
  155.  *              ByteAlignment (1, 2, 3, or 4)
  156.  *
  157.  * DESCRIPTION: Generate an optimal access width for fields defined with the
  158.  *              AnyAcc keyword.
  159.  *
  160.  * NOTE: Need to have the RegionLength in order to check for boundary
  161.  *       conditions (end-of-region).  However, the RegionLength is a deferred
  162.  *       operation.  Therefore, to complete this implementation, the generation
  163.  *       of this access width must be deferred until the region length has
  164.  *       been evaluated.
  165.  *
  166.  ******************************************************************************/
  167.  
  168. static UINT32
  169. AcpiExGenerateAccess (
  170.     UINT32                  FieldBitOffset,
  171.     UINT32                  FieldBitLength,
  172.     UINT32                  RegionLength)
  173. {
  174.     UINT32                  FieldByteLength;
  175.     UINT32                  FieldByteOffset;
  176.     UINT32                  FieldByteEndOffset;
  177.     UINT32                  AccessByteWidth;
  178.     UINT32                  FieldStartOffset;
  179.     UINT32                  FieldEndOffset;
  180.     UINT32                  MinimumAccessWidth = 0xFFFFFFFF;
  181.     UINT32                  MinimumAccesses = 0xFFFFFFFF;
  182.     UINT32                  Accesses;
  183.  
  184.  
  185.     ACPI_FUNCTION_TRACE (ExGenerateAccess);
  186.  
  187.  
  188.     /* Round Field start offset and length to "minimal" byte boundaries */
  189.  
  190.     FieldByteOffset    = ACPI_DIV_8 (ACPI_ROUND_DOWN (FieldBitOffset, 8));
  191.     FieldByteEndOffset = ACPI_DIV_8 (ACPI_ROUND_UP   (FieldBitLength +
  192.                                                       FieldBitOffset, 8));
  193.     FieldByteLength    = FieldByteEndOffset - FieldByteOffset;
  194.  
  195.     ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
  196.         "Bit length %u, Bit offset %u\n",
  197.         FieldBitLength, FieldBitOffset));
  198.  
  199.     ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
  200.         "Byte Length %u, Byte Offset %u, End Offset %u\n",
  201.         FieldByteLength, FieldByteOffset, FieldByteEndOffset));
  202.  
  203.     /*
  204.      * Iterative search for the maximum access width that is both aligned
  205.      * and does not go beyond the end of the region
  206.      *
  207.      * Start at ByteAcc and work upwards to QwordAcc max. (1,2,4,8 bytes)
  208.      */
  209.     for (AccessByteWidth = 1; AccessByteWidth <= 8; AccessByteWidth <<= 1)
  210.     {
  211.         /*
  212.          * 1) Round end offset up to next access boundary and make sure that
  213.          *    this does not go beyond the end of the parent region.
  214.          * 2) When the Access width is greater than the FieldByteLength, we
  215.          *    are done. (This does not optimize for the perfectly aligned
  216.          *    case yet).
  217.          */
  218.         if (ACPI_ROUND_UP (FieldByteEndOffset, AccessByteWidth) <= RegionLength)
  219.         {
  220.             FieldStartOffset =
  221.                 ACPI_ROUND_DOWN (FieldByteOffset, AccessByteWidth) /
  222.                 AccessByteWidth;
  223.  
  224.             FieldEndOffset =
  225.                 ACPI_ROUND_UP ((FieldByteLength + FieldByteOffset),
  226.                     AccessByteWidth) / AccessByteWidth;
  227.  
  228.             Accesses = FieldEndOffset - FieldStartOffset;
  229.  
  230.             ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
  231.                 "AccessWidth %u end is within region\n", AccessByteWidth));
  232.  
  233.             ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
  234.                 "Field Start %u, Field End %u -- requires %u accesses\n",
  235.                 FieldStartOffset, FieldEndOffset, Accesses));
  236.  
  237.             /* Single access is optimal */
  238.  
  239.             if (Accesses <= 1)
  240.             {
  241.                 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
  242.                     "Entire field can be accessed with one operation of size %u\n",
  243.                     AccessByteWidth));
  244.                 return_VALUE (AccessByteWidth);
  245.             }
  246.  
  247.             /*
  248.              * Fits in the region, but requires more than one read/write.
  249.              * try the next wider access on next iteration
  250.              */
  251.             if (Accesses < MinimumAccesses)
  252.             {
  253.                 MinimumAccesses    = Accesses;
  254.                 MinimumAccessWidth = AccessByteWidth;
  255.             }
  256.         }
  257.         else
  258.         {
  259.             ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
  260.                 "AccessWidth %u end is NOT within region\n", AccessByteWidth));
  261.             if (AccessByteWidth == 1)
  262.             {
  263.                 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
  264.                     "Field goes beyond end-of-region!\n"));
  265.  
  266.                 /* Field does not fit in the region at all */
  267.  
  268.                 return_VALUE (0);
  269.             }
  270.  
  271.             /*
  272.              * This width goes beyond the end-of-region, back off to
  273.              * previous access
  274.              */
  275.             ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
  276.                 "Backing off to previous optimal access width of %u\n",
  277.                 MinimumAccessWidth));
  278.             return_VALUE (MinimumAccessWidth);
  279.         }
  280.     }
  281.  
  282.     /*
  283.      * Could not read/write field with one operation,
  284.      * just use max access width
  285.      */
  286.     ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
  287.         "Cannot access field in one operation, using width 8\n"));
  288.     return_VALUE (8);
  289. }
  290. #endif /* ACPI_UNDER_DEVELOPMENT */
  291.  
  292.  
  293. /*******************************************************************************
  294.  *
  295.  * FUNCTION:    AcpiExDecodeFieldAccess
  296.  *
  297.  * PARAMETERS:  ObjDesc             - Field object
  298.  *              FieldFlags          - Encoded fieldflags (contains access bits)
  299.  *              ReturnByteAlignment - Where the byte alignment is returned
  300.  *
  301.  * RETURN:      Field granularity (8, 16, 32 or 64) and
  302.  *              ByteAlignment (1, 2, 3, or 4)
  303.  *
  304.  * DESCRIPTION: Decode the AccessType bits of a field definition.
  305.  *
  306.  ******************************************************************************/
  307.  
  308. static UINT32
  309. AcpiExDecodeFieldAccess (
  310.     ACPI_OPERAND_OBJECT     *ObjDesc,
  311.     UINT8                   FieldFlags,
  312.     UINT32                  *ReturnByteAlignment)
  313. {
  314.     UINT32                  Access;
  315.     UINT32                  ByteAlignment;
  316.     UINT32                  BitLength;
  317.  
  318.  
  319.     ACPI_FUNCTION_TRACE (ExDecodeFieldAccess);
  320.  
  321.  
  322.     Access = (FieldFlags & AML_FIELD_ACCESS_TYPE_MASK);
  323.  
  324.     switch (Access)
  325.     {
  326.     case AML_FIELD_ACCESS_ANY:
  327.  
  328. #ifdef ACPI_UNDER_DEVELOPMENT
  329.         ByteAlignment =
  330.             AcpiExGenerateAccess (ObjDesc->CommonField.StartFieldBitOffset,
  331.                 ObjDesc->CommonField.BitLength,
  332.                 0xFFFFFFFF /* Temp until we pass RegionLength as parameter */);
  333.         BitLength = ByteAlignment * 8;
  334. #endif
  335.  
  336.         ByteAlignment = 1;
  337.         BitLength = 8;
  338.         break;
  339.  
  340.     case AML_FIELD_ACCESS_BYTE:
  341.     case AML_FIELD_ACCESS_BUFFER:   /* ACPI 2.0 (SMBus Buffer) */
  342.         ByteAlignment = 1;
  343.         BitLength     = 8;
  344.         break;
  345.  
  346.     case AML_FIELD_ACCESS_WORD:
  347.         ByteAlignment = 2;
  348.         BitLength     = 16;
  349.         break;
  350.  
  351.     case AML_FIELD_ACCESS_DWORD:
  352.         ByteAlignment = 4;
  353.         BitLength     = 32;
  354.         break;
  355.  
  356.     case AML_FIELD_ACCESS_QWORD:    /* ACPI 2.0 */
  357.         ByteAlignment = 8;
  358.         BitLength     = 64;
  359.         break;
  360.  
  361.     default:
  362.         /* Invalid field access type */
  363.  
  364.         ACPI_ERROR ((AE_INFO,
  365.             "Unknown field access type 0x%X",
  366.             Access));
  367.         return_UINT32 (0);
  368.     }
  369.  
  370.     if (ObjDesc->Common.Type == ACPI_TYPE_BUFFER_FIELD)
  371.     {
  372.         /*
  373.          * BufferField access can be on any byte boundary, so the
  374.          * ByteAlignment is always 1 byte -- regardless of any ByteAlignment
  375.          * implied by the field access type.
  376.          */
  377.         ByteAlignment = 1;
  378.     }
  379.  
  380.     *ReturnByteAlignment = ByteAlignment;
  381.     return_UINT32 (BitLength);
  382. }
  383.  
  384.  
  385. /*******************************************************************************
  386.  *
  387.  * FUNCTION:    AcpiExPrepCommonFieldObject
  388.  *
  389.  * PARAMETERS:  ObjDesc             - The field object
  390.  *              FieldFlags          - Access, LockRule, and UpdateRule.
  391.  *                                    The format of a FieldFlag is described
  392.  *                                    in the ACPI specification
  393.  *              FieldAttribute      - Special attributes (not used)
  394.  *              FieldBitPosition    - Field start position
  395.  *              FieldBitLength      - Field length in number of bits
  396.  *
  397.  * RETURN:      Status
  398.  *
  399.  * DESCRIPTION: Initialize the areas of the field object that are common
  400.  *              to the various types of fields.  Note: This is very "sensitive"
  401.  *              code because we are solving the general case for field
  402.  *              alignment.
  403.  *
  404.  ******************************************************************************/
  405.  
  406. ACPI_STATUS
  407. AcpiExPrepCommonFieldObject (
  408.     ACPI_OPERAND_OBJECT     *ObjDesc,
  409.     UINT8                   FieldFlags,
  410.     UINT8                   FieldAttribute,
  411.     UINT32                  FieldBitPosition,
  412.     UINT32                  FieldBitLength)
  413. {
  414.     UINT32                  AccessBitWidth;
  415.     UINT32                  ByteAlignment;
  416.     UINT32                  NearestByteAddress;
  417.  
  418.  
  419.     ACPI_FUNCTION_TRACE (ExPrepCommonFieldObject);
  420.  
  421.  
  422.     /*
  423.      * Note: the structure being initialized is the
  424.      * ACPI_COMMON_FIELD_INFO;  No structure fields outside of the common
  425.      * area are initialized by this procedure.
  426.      */
  427.     ObjDesc->CommonField.FieldFlags = FieldFlags;
  428.     ObjDesc->CommonField.Attribute  = FieldAttribute;
  429.     ObjDesc->CommonField.BitLength  = FieldBitLength;
  430.  
  431.     /*
  432.      * Decode the access type so we can compute offsets.  The access type gives
  433.      * two pieces of information - the width of each field access and the
  434.      * necessary ByteAlignment (address granularity) of the access.
  435.      *
  436.      * For AnyAcc, the AccessBitWidth is the largest width that is both
  437.      * necessary and possible in an attempt to access the whole field in one
  438.      * I/O operation.  However, for AnyAcc, the ByteAlignment is always one
  439.      * byte.
  440.      *
  441.      * For all Buffer Fields, the ByteAlignment is always one byte.
  442.      *
  443.      * For all other access types (Byte, Word, Dword, Qword), the Bitwidth is
  444.      * the same (equivalent) as the ByteAlignment.
  445.      */
  446.     AccessBitWidth = AcpiExDecodeFieldAccess (ObjDesc, FieldFlags,
  447.                         &ByteAlignment);
  448.     if (!AccessBitWidth)
  449.     {
  450.         return_ACPI_STATUS (AE_AML_OPERAND_VALUE);
  451.     }
  452.  
  453.     /* Setup width (access granularity) fields (values are: 1, 2, 4, 8) */
  454.  
  455.     ObjDesc->CommonField.AccessByteWidth = (UINT8)
  456.         ACPI_DIV_8 (AccessBitWidth);
  457.  
  458.     /*
  459.      * BaseByteOffset is the address of the start of the field within the
  460.      * region.  It is the byte address of the first *datum* (field-width data
  461.      * unit) of the field. (i.e., the first datum that contains at least the
  462.      * first *bit* of the field.)
  463.      *
  464.      * Note: ByteAlignment is always either equal to the AccessBitWidth or 8
  465.      * (Byte access), and it defines the addressing granularity of the parent
  466.      * region or buffer.
  467.      */
  468.     NearestByteAddress =
  469.         ACPI_ROUND_BITS_DOWN_TO_BYTES (FieldBitPosition);
  470.     ObjDesc->CommonField.BaseByteOffset = (UINT32)
  471.         ACPI_ROUND_DOWN (NearestByteAddress, ByteAlignment);
  472.  
  473.     /*
  474.      * StartFieldBitOffset is the offset of the first bit of the field within
  475.      * a field datum.
  476.      */
  477.     ObjDesc->CommonField.StartFieldBitOffset = (UINT8)
  478.         (FieldBitPosition - ACPI_MUL_8 (ObjDesc->CommonField.BaseByteOffset));
  479.  
  480.     return_ACPI_STATUS (AE_OK);
  481. }
  482.  
  483.  
  484. /*******************************************************************************
  485.  *
  486.  * FUNCTION:    AcpiExPrepFieldValue
  487.  *
  488.  * PARAMETERS:  Info    - Contains all field creation info
  489.  *
  490.  * RETURN:      Status
  491.  *
  492.  * DESCRIPTION: Construct an ACPI_OPERAND_OBJECT of type DefField and
  493.  *              connect it to the parent Node.
  494.  *
  495.  ******************************************************************************/
  496.  
  497. ACPI_STATUS
  498. AcpiExPrepFieldValue (
  499.     ACPI_CREATE_FIELD_INFO  *Info)
  500. {
  501.     ACPI_OPERAND_OBJECT     *ObjDesc;
  502.     ACPI_OPERAND_OBJECT     *SecondDesc = NULL;
  503.     ACPI_STATUS             Status;
  504.     UINT32                  AccessByteWidth;
  505.     UINT32                  Type;
  506.  
  507.  
  508.     ACPI_FUNCTION_TRACE (ExPrepFieldValue);
  509.  
  510.  
  511.     /* Parameter validation */
  512.  
  513.     if (Info->FieldType != ACPI_TYPE_LOCAL_INDEX_FIELD)
  514.     {
  515.         if (!Info->RegionNode)
  516.         {
  517.             ACPI_ERROR ((AE_INFO, "Null RegionNode"));
  518.             return_ACPI_STATUS (AE_AML_NO_OPERAND);
  519.         }
  520.  
  521.         Type = AcpiNsGetType (Info->RegionNode);
  522.         if (Type != ACPI_TYPE_REGION)
  523.         {
  524.             ACPI_ERROR ((AE_INFO, "Needed Region, found type 0x%X (%s)",
  525.                 Type, AcpiUtGetTypeName (Type)));
  526.  
  527.             return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
  528.         }
  529.     }
  530.  
  531.     /* Allocate a new field object */
  532.  
  533.     ObjDesc = AcpiUtCreateInternalObject (Info->FieldType);
  534.     if (!ObjDesc)
  535.     {
  536.         return_ACPI_STATUS (AE_NO_MEMORY);
  537.     }
  538.  
  539.     /* Initialize areas of the object that are common to all fields */
  540.  
  541.     ObjDesc->CommonField.Node = Info->FieldNode;
  542.     Status = AcpiExPrepCommonFieldObject (ObjDesc,
  543.                 Info->FieldFlags, Info->Attribute,
  544.                 Info->FieldBitPosition, Info->FieldBitLength);
  545.     if (ACPI_FAILURE (Status))
  546.     {
  547.         AcpiUtDeleteObjectDesc (ObjDesc);
  548.         return_ACPI_STATUS (Status);
  549.     }
  550.  
  551.     /* Initialize areas of the object that are specific to the field type */
  552.  
  553.     switch (Info->FieldType)
  554.     {
  555.     case ACPI_TYPE_LOCAL_REGION_FIELD:
  556.  
  557.         ObjDesc->Field.RegionObj = AcpiNsGetAttachedObject (Info->RegionNode);
  558.  
  559.         /* Allow full data read from EC address space */
  560.  
  561.         if ((ObjDesc->Field.RegionObj->Region.SpaceId == ACPI_ADR_SPACE_EC) &&
  562.             (ObjDesc->CommonField.BitLength > 8))
  563.         {
  564.             AccessByteWidth = ACPI_ROUND_BITS_UP_TO_BYTES (
  565.                 ObjDesc->CommonField.BitLength);
  566.  
  567.             /* Maximum byte width supported is 255 */
  568.  
  569.             if (AccessByteWidth < 256)
  570.             {
  571.                 ObjDesc->CommonField.AccessByteWidth = (UINT8) AccessByteWidth;
  572.             }
  573.         }
  574.  
  575.         /* An additional reference for the container */
  576.  
  577.         AcpiUtAddReference (ObjDesc->Field.RegionObj);
  578.  
  579.         ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
  580.             "RegionField: BitOff %X, Off %X, Gran %X, Region %p\n",
  581.             ObjDesc->Field.StartFieldBitOffset, ObjDesc->Field.BaseByteOffset,
  582.             ObjDesc->Field.AccessByteWidth, ObjDesc->Field.RegionObj));
  583.         break;
  584.  
  585.  
  586.     case ACPI_TYPE_LOCAL_BANK_FIELD:
  587.  
  588.         ObjDesc->BankField.Value = Info->BankValue;
  589.         ObjDesc->BankField.RegionObj =
  590.             AcpiNsGetAttachedObject (Info->RegionNode);
  591.         ObjDesc->BankField.BankObj =
  592.             AcpiNsGetAttachedObject (Info->RegisterNode);
  593.  
  594.         /* An additional reference for the attached objects */
  595.  
  596.         AcpiUtAddReference (ObjDesc->BankField.RegionObj);
  597.         AcpiUtAddReference (ObjDesc->BankField.BankObj);
  598.  
  599.         ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
  600.             "Bank Field: BitOff %X, Off %X, Gran %X, Region %p, BankReg %p\n",
  601.             ObjDesc->BankField.StartFieldBitOffset,
  602.             ObjDesc->BankField.BaseByteOffset,
  603.             ObjDesc->Field.AccessByteWidth,
  604.             ObjDesc->BankField.RegionObj,
  605.             ObjDesc->BankField.BankObj));
  606.  
  607.         /*
  608.          * Remember location in AML stream of the field unit
  609.          * opcode and operands -- since the BankValue
  610.          * operands must be evaluated.
  611.          */
  612.         SecondDesc = ObjDesc->Common.NextObject;
  613.         SecondDesc->Extra.AmlStart = ACPI_CAST_PTR (ACPI_PARSE_OBJECT,
  614.             Info->DataRegisterNode)->Named.Data;
  615.         SecondDesc->Extra.AmlLength = ACPI_CAST_PTR (ACPI_PARSE_OBJECT,
  616.             Info->DataRegisterNode)->Named.Length;
  617.  
  618.         break;
  619.  
  620.  
  621.     case ACPI_TYPE_LOCAL_INDEX_FIELD:
  622.  
  623.         /* Get the Index and Data registers */
  624.  
  625.         ObjDesc->IndexField.IndexObj =
  626.             AcpiNsGetAttachedObject (Info->RegisterNode);
  627.         ObjDesc->IndexField.DataObj =
  628.             AcpiNsGetAttachedObject (Info->DataRegisterNode);
  629.  
  630.         if (!ObjDesc->IndexField.DataObj || !ObjDesc->IndexField.IndexObj)
  631.         {
  632.             ACPI_ERROR ((AE_INFO, "Null Index Object during field prep"));
  633.             AcpiUtDeleteObjectDesc (ObjDesc);
  634.             return_ACPI_STATUS (AE_AML_INTERNAL);
  635.         }
  636.  
  637.         /* An additional reference for the attached objects */
  638.  
  639.         AcpiUtAddReference (ObjDesc->IndexField.DataObj);
  640.         AcpiUtAddReference (ObjDesc->IndexField.IndexObj);
  641.  
  642.         /*
  643.          * April 2006: Changed to match MS behavior
  644.          *
  645.          * The value written to the Index register is the byte offset of the
  646.          * target field in units of the granularity of the IndexField
  647.          *
  648.          * Previously, the value was calculated as an index in terms of the
  649.          * width of the Data register, as below:
  650.          *
  651.          *      ObjDesc->IndexField.Value = (UINT32)
  652.          *          (Info->FieldBitPosition / ACPI_MUL_8 (
  653.          *              ObjDesc->Field.AccessByteWidth));
  654.          *
  655.          * February 2006: Tried value as a byte offset:
  656.          *      ObjDesc->IndexField.Value = (UINT32)
  657.          *          ACPI_DIV_8 (Info->FieldBitPosition);
  658.          */
  659.         ObjDesc->IndexField.Value = (UINT32) ACPI_ROUND_DOWN (
  660.             ACPI_DIV_8 (Info->FieldBitPosition),
  661.             ObjDesc->IndexField.AccessByteWidth);
  662.  
  663.         ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
  664.             "IndexField: BitOff %X, Off %X, Value %X, Gran %X, Index %p, Data %p\n",
  665.             ObjDesc->IndexField.StartFieldBitOffset,
  666.             ObjDesc->IndexField.BaseByteOffset,
  667.             ObjDesc->IndexField.Value,
  668.             ObjDesc->Field.AccessByteWidth,
  669.             ObjDesc->IndexField.IndexObj,
  670.             ObjDesc->IndexField.DataObj));
  671.         break;
  672.  
  673.     default:
  674.         /* No other types should get here */
  675.         break;
  676.     }
  677.  
  678.     /*
  679.      * Store the constructed descriptor (ObjDesc) into the parent Node,
  680.      * preserving the current type of that NamedObj.
  681.      */
  682.     Status = AcpiNsAttachObject (Info->FieldNode, ObjDesc,
  683.                 AcpiNsGetType (Info->FieldNode));
  684.  
  685.     ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "Set NamedObj %p [%4.4s], ObjDesc %p\n",
  686.         Info->FieldNode, AcpiUtGetNodeName (Info->FieldNode), ObjDesc));
  687.  
  688.     /* Remove local reference to the object */
  689.  
  690.     AcpiUtRemoveReference (ObjDesc);
  691.     return_ACPI_STATUS (Status);
  692. }
  693.  
  694.