text: 
  /******************************************************************************
   *
   * Module Name: exprep - ACPI AML (p-code) execution - field prep utilities
   *
   *****************************************************************************/
  
  /*
   * Copyright (C) 2000 - 2011, Intel Corp.
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions, and the following disclaimer,
   *    without modification.
   * 2. Redistributions in binary form must reproduce at minimum a disclaimer
   *    substantially similar to the "NO WARRANTY" disclaimer below
   *    ("Disclaimer") and any redistribution must be conditioned upon
   *    including a substantially similar Disclaimer requirement for further
   *    binary redistribution.
   * 3. Neither the names of the above-listed copyright holders nor the names
   *    of any contributors may be used to endorse or promote products derived
   *    from this software without specific prior written permission.
   *
   * Alternatively, this software may be distributed under the terms of the
   * GNU General Public License ("GPL") version 2 as published by the Free
   * Software Foundation.
   *
   * NO WARRANTY
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
   * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGES.
   */
  
  #define __EXPREP_C__
  
  #include <contrib/dev/acpica/include/acpi.h>
  #include <contrib/dev/acpica/include/accommon.h>
  #include <contrib/dev/acpica/include/acinterp.h>
  #include <contrib/dev/acpica/include/amlcode.h>
  #include <contrib/dev/acpica/include/acnamesp.h>
  
  
  #define _COMPONENT          ACPI_EXECUTER
          ACPI_MODULE_NAME    ("exprep")
  
  /* Local prototypes */
  
  static UINT32
  AcpiExDecodeFieldAccess (
      ACPI_OPERAND_OBJECT     *ObjDesc,
      UINT8                   FieldFlags,
      UINT32                  *ReturnByteAlignment);
  
  
  #ifdef ACPI_UNDER_DEVELOPMENT
  
  static UINT32
  AcpiExGenerateAccess (
      UINT32                  FieldBitOffset,
      UINT32                  FieldBitLength,
      UINT32                  RegionLength);
  
  /*******************************************************************************
   *
   * FUNCTION:    AcpiExGenerateAccess
   *
   * PARAMETERS:  FieldBitOffset      - Start of field within parent region/buffer
   *              FieldBitLength      - Length of field in bits
   *              RegionLength        - Length of parent in bytes
   *
   * RETURN:      Field granularity (8, 16, 32 or 64) and
   *              ByteAlignment (1, 2, 3, or 4)
   *
   * DESCRIPTION: Generate an optimal access width for fields defined with the
   *              AnyAcc keyword.
   *
   * NOTE: Need to have the RegionLength in order to check for boundary
   *       conditions (end-of-region).  However, the RegionLength is a deferred
   *       operation.  Therefore, to complete this implementation, the generation
   *       of this access width must be deferred until the region length has
   *       been evaluated.
   *
   ******************************************************************************/
  
  static UINT32
  AcpiExGenerateAccess (
      UINT32                  FieldBitOffset,
      UINT32                  FieldBitLength,
      UINT32                  RegionLength)
  {
      UINT32                  FieldByteLength;
      UINT32                  FieldByteOffset;
      UINT32                  FieldByteEndOffset;
      UINT32                  AccessByteWidth;
      UINT32                  FieldStartOffset;
      UINT32                  FieldEndOffset;
      UINT32                  MinimumAccessWidth = 0xFFFFFFFF;
      UINT32                  MinimumAccesses = 0xFFFFFFFF;
      UINT32                  Accesses;
  
  
      ACPI_FUNCTION_TRACE (ExGenerateAccess);
  
  
      /* Round Field start offset and length to "minimal" byte boundaries */
  
      FieldByteOffset    = ACPI_DIV_8 (ACPI_ROUND_DOWN (FieldBitOffset, 8));
      FieldByteEndOffset = ACPI_DIV_8 (ACPI_ROUND_UP   (FieldBitLength +
                                                        FieldBitOffset, 8));
      FieldByteLength    = FieldByteEndOffset - FieldByteOffset;
  
      ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
          "Bit length %u, Bit offset %u\n",
          FieldBitLength, FieldBitOffset));
  
      ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
          "Byte Length %u, Byte Offset %u, End Offset %u\n",
          FieldByteLength, FieldByteOffset, FieldByteEndOffset));
  
      /*
       * Iterative search for the maximum access width that is both aligned
       * and does not go beyond the end of the region
       *
       * Start at ByteAcc and work upwards to QwordAcc max. (1,2,4,8 bytes)
       */
      for (AccessByteWidth = 1; AccessByteWidth <= 8; AccessByteWidth <<= 1)
      {
          /*
           * 1) Round end offset up to next access boundary and make sure that
           *    this does not go beyond the end of the parent region.
           * 2) When the Access width is greater than the FieldByteLength, we
           *    are done. (This does not optimize for the perfectly aligned
           *    case yet).
           */
          if (ACPI_ROUND_UP (FieldByteEndOffset, AccessByteWidth) <= RegionLength)
          {
              FieldStartOffset =
                  ACPI_ROUND_DOWN (FieldByteOffset, AccessByteWidth) /
                  AccessByteWidth;
  
              FieldEndOffset =
                  ACPI_ROUND_UP ((FieldByteLength + FieldByteOffset),
                      AccessByteWidth) / AccessByteWidth;
  
              Accesses = FieldEndOffset - FieldStartOffset;
  
              ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
                  "AccessWidth %u end is within region\n", AccessByteWidth));
  
              ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
                  "Field Start %u, Field End %u -- requires %u accesses\n",
                  FieldStartOffset, FieldEndOffset, Accesses));
  
              /* Single access is optimal */
  
              if (Accesses <= 1)
              {
                  ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
                      "Entire field can be accessed with one operation of size %u\n",
                      AccessByteWidth));
                  return_VALUE (AccessByteWidth);
              }
  
              /*
               * Fits in the region, but requires more than one read/write.
               * try the next wider access on next iteration
               */
              if (Accesses < MinimumAccesses)
              {
                  MinimumAccesses    = Accesses;
                  MinimumAccessWidth = AccessByteWidth;
              }
          }
          else
          {
              ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
                  "AccessWidth %u end is NOT within region\n", AccessByteWidth));
              if (AccessByteWidth == 1)
              {
                  ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
                      "Field goes beyond end-of-region!\n"));
  
                  /* Field does not fit in the region at all */
  
                  return_VALUE (0);
              }
  
              /*
               * This width goes beyond the end-of-region, back off to
               * previous access
               */
              ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
                  "Backing off to previous optimal access width of %u\n",
                  MinimumAccessWidth));
              return_VALUE (MinimumAccessWidth);
          }
      }
  
      /*
       * Could not read/write field with one operation,
       * just use max access width
       */
      ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
          "Cannot access field in one operation, using width 8\n"));
      return_VALUE (8);
  }
  #endif /* ACPI_UNDER_DEVELOPMENT */
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AcpiExDecodeFieldAccess
   *
   * PARAMETERS:  ObjDesc             - Field object
   *              FieldFlags          - Encoded fieldflags (contains access bits)
   *              ReturnByteAlignment - Where the byte alignment is returned
   *
   * RETURN:      Field granularity (8, 16, 32 or 64) and
   *              ByteAlignment (1, 2, 3, or 4)
   *
   * DESCRIPTION: Decode the AccessType bits of a field definition.
   *
   ******************************************************************************/
  
  static UINT32
  AcpiExDecodeFieldAccess (
      ACPI_OPERAND_OBJECT     *ObjDesc,
      UINT8                   FieldFlags,
      UINT32                  *ReturnByteAlignment)
  {
      UINT32                  Access;
      UINT32                  ByteAlignment;
      UINT32                  BitLength;
  
  
      ACPI_FUNCTION_TRACE (ExDecodeFieldAccess);
  
  
      Access = (FieldFlags & AML_FIELD_ACCESS_TYPE_MASK);
  
      switch (Access)
      {
      case AML_FIELD_ACCESS_ANY:
  
  #ifdef ACPI_UNDER_DEVELOPMENT
          ByteAlignment =
              AcpiExGenerateAccess (ObjDesc->CommonField.StartFieldBitOffset,
                  ObjDesc->CommonField.BitLength,
                  0xFFFFFFFF /* Temp until we pass RegionLength as parameter */);
          BitLength = ByteAlignment * 8;
  #endif
  
          ByteAlignment = 1;
          BitLength = 8;
          break;
  
      case AML_FIELD_ACCESS_BYTE:
      case AML_FIELD_ACCESS_BUFFER:   /* ACPI 2.0 (SMBus Buffer) */
          ByteAlignment = 1;
          BitLength     = 8;
          break;
  
      case AML_FIELD_ACCESS_WORD:
          ByteAlignment = 2;
          BitLength     = 16;
          break;
  
      case AML_FIELD_ACCESS_DWORD:
          ByteAlignment = 4;
          BitLength     = 32;
          break;
  
      case AML_FIELD_ACCESS_QWORD:    /* ACPI 2.0 */
          ByteAlignment = 8;
          BitLength     = 64;
          break;
  
      default:
          /* Invalid field access type */
  
          ACPI_ERROR ((AE_INFO,
              "Unknown field access type 0x%X",
              Access));
          return_UINT32 (0);
      }
  
      if (ObjDesc->Common.Type == ACPI_TYPE_BUFFER_FIELD)
      {
          /*
           * BufferField access can be on any byte boundary, so the
           * ByteAlignment is always 1 byte -- regardless of any ByteAlignment
           * implied by the field access type.
           */
          ByteAlignment = 1;
      }
  
      *ReturnByteAlignment = ByteAlignment;
      return_UINT32 (BitLength);
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AcpiExPrepCommonFieldObject
   *
   * PARAMETERS:  ObjDesc             - The field object
   *              FieldFlags          - Access, LockRule, and UpdateRule.
   *                                    The format of a FieldFlag is described
   *                                    in the ACPI specification
   *              FieldAttribute      - Special attributes (not used)
   *              FieldBitPosition    - Field start position
   *              FieldBitLength      - Field length in number of bits
   *
   * RETURN:      Status
   *
   * DESCRIPTION: Initialize the areas of the field object that are common
   *              to the various types of fields.  Note: This is very "sensitive"
   *              code because we are solving the general case for field
   *              alignment.
   *
   ******************************************************************************/
  
  ACPI_STATUS
  AcpiExPrepCommonFieldObject (
      ACPI_OPERAND_OBJECT     *ObjDesc,
      UINT8                   FieldFlags,
      UINT8                   FieldAttribute,
      UINT32                  FieldBitPosition,
      UINT32                  FieldBitLength)
  {
      UINT32                  AccessBitWidth;
      UINT32                  ByteAlignment;
      UINT32                  NearestByteAddress;
  
  
      ACPI_FUNCTION_TRACE (ExPrepCommonFieldObject);
  
  
      /*
       * Note: the structure being initialized is the
       * ACPI_COMMON_FIELD_INFO;  No structure fields outside of the common
       * area are initialized by this procedure.
       */
      ObjDesc->CommonField.FieldFlags = FieldFlags;
      ObjDesc->CommonField.Attribute  = FieldAttribute;
      ObjDesc->CommonField.BitLength  = FieldBitLength;
  
      /*
       * Decode the access type so we can compute offsets.  The access type gives
       * two pieces of information - the width of each field access and the
       * necessary ByteAlignment (address granularity) of the access.
       *
       * For AnyAcc, the AccessBitWidth is the largest width that is both
       * necessary and possible in an attempt to access the whole field in one
       * I/O operation.  However, for AnyAcc, the ByteAlignment is always one
       * byte.
       *
       * For all Buffer Fields, the ByteAlignment is always one byte.
       *
       * For all other access types (Byte, Word, Dword, Qword), the Bitwidth is
       * the same (equivalent) as the ByteAlignment.
       */
      AccessBitWidth = AcpiExDecodeFieldAccess (ObjDesc, FieldFlags,
                          &ByteAlignment);
      if (!AccessBitWidth)
      {
          return_ACPI_STATUS (AE_AML_OPERAND_VALUE);
      }
  
      /* Setup width (access granularity) fields (values are: 1, 2, 4, 8) */
  
      ObjDesc->CommonField.AccessByteWidth = (UINT8)
          ACPI_DIV_8 (AccessBitWidth);
  
      /*
       * BaseByteOffset is the address of the start of the field within the
       * region.  It is the byte address of the first *datum* (field-width data
       * unit) of the field. (i.e., the first datum that contains at least the
       * first *bit* of the field.)
       *
       * Note: ByteAlignment is always either equal to the AccessBitWidth or 8
       * (Byte access), and it defines the addressing granularity of the parent
       * region or buffer.
       */
      NearestByteAddress =
          ACPI_ROUND_BITS_DOWN_TO_BYTES (FieldBitPosition);
      ObjDesc->CommonField.BaseByteOffset = (UINT32)
          ACPI_ROUND_DOWN (NearestByteAddress, ByteAlignment);
  
      /*
       * StartFieldBitOffset is the offset of the first bit of the field within
       * a field datum.
       */
      ObjDesc->CommonField.StartFieldBitOffset = (UINT8)
          (FieldBitPosition - ACPI_MUL_8 (ObjDesc->CommonField.BaseByteOffset));
  
      return_ACPI_STATUS (AE_OK);
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AcpiExPrepFieldValue
   *
   * PARAMETERS:  Info    - Contains all field creation info
   *
   * RETURN:      Status
   *
   * DESCRIPTION: Construct an ACPI_OPERAND_OBJECT of type DefField and
   *              connect it to the parent Node.
   *
   ******************************************************************************/
  
  ACPI_STATUS
  AcpiExPrepFieldValue (
      ACPI_CREATE_FIELD_INFO  *Info)
  {
      ACPI_OPERAND_OBJECT     *ObjDesc;
      ACPI_OPERAND_OBJECT     *SecondDesc = NULL;
      ACPI_STATUS             Status;
      UINT32                  AccessByteWidth;
      UINT32                  Type;
  
  
      ACPI_FUNCTION_TRACE (ExPrepFieldValue);
  
  
      /* Parameter validation */
  
      if (Info->FieldType != ACPI_TYPE_LOCAL_INDEX_FIELD)
      {
          if (!Info->RegionNode)
          {
              ACPI_ERROR ((AE_INFO, "Null RegionNode"));
              return_ACPI_STATUS (AE_AML_NO_OPERAND);
          }
  
          Type = AcpiNsGetType (Info->RegionNode);
          if (Type != ACPI_TYPE_REGION)
          {
              ACPI_ERROR ((AE_INFO, "Needed Region, found type 0x%X (%s)",
                  Type, AcpiUtGetTypeName (Type)));
  
              return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
          }
      }
  
      /* Allocate a new field object */
  
      ObjDesc = AcpiUtCreateInternalObject (Info->FieldType);
      if (!ObjDesc)
      {
          return_ACPI_STATUS (AE_NO_MEMORY);
      }
  
      /* Initialize areas of the object that are common to all fields */
  
      ObjDesc->CommonField.Node = Info->FieldNode;
      Status = AcpiExPrepCommonFieldObject (ObjDesc,
                  Info->FieldFlags, Info->Attribute,
                  Info->FieldBitPosition, Info->FieldBitLength);
      if (ACPI_FAILURE (Status))
      {
          AcpiUtDeleteObjectDesc (ObjDesc);
          return_ACPI_STATUS (Status);
      }
  
      /* Initialize areas of the object that are specific to the field type */
  
      switch (Info->FieldType)
      {
      case ACPI_TYPE_LOCAL_REGION_FIELD:
  
          ObjDesc->Field.RegionObj = AcpiNsGetAttachedObject (Info->RegionNode);
  
          /* Allow full data read from EC address space */
  
          if ((ObjDesc->Field.RegionObj->Region.SpaceId == ACPI_ADR_SPACE_EC) &&
              (ObjDesc->CommonField.BitLength > 8))
          {
              AccessByteWidth = ACPI_ROUND_BITS_UP_TO_BYTES (
                  ObjDesc->CommonField.BitLength);
  
              /* Maximum byte width supported is 255 */
  
              if (AccessByteWidth < 256)
              {
                  ObjDesc->CommonField.AccessByteWidth = (UINT8) AccessByteWidth;
              }
          }
  
          /* An additional reference for the container */
  
          AcpiUtAddReference (ObjDesc->Field.RegionObj);
  
          ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
              "RegionField: BitOff %X, Off %X, Gran %X, Region %p\n",
              ObjDesc->Field.StartFieldBitOffset, ObjDesc->Field.BaseByteOffset,
              ObjDesc->Field.AccessByteWidth, ObjDesc->Field.RegionObj));
          break;
  
  
      case ACPI_TYPE_LOCAL_BANK_FIELD:
  
          ObjDesc->BankField.Value = Info->BankValue;
          ObjDesc->BankField.RegionObj =
              AcpiNsGetAttachedObject (Info->RegionNode);
          ObjDesc->BankField.BankObj =
              AcpiNsGetAttachedObject (Info->RegisterNode);
  
          /* An additional reference for the attached objects */
  
          AcpiUtAddReference (ObjDesc->BankField.RegionObj);
          AcpiUtAddReference (ObjDesc->BankField.BankObj);
  
          ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
              "Bank Field: BitOff %X, Off %X, Gran %X, Region %p, BankReg %p\n",
              ObjDesc->BankField.StartFieldBitOffset,
              ObjDesc->BankField.BaseByteOffset,
              ObjDesc->Field.AccessByteWidth,
              ObjDesc->BankField.RegionObj,
              ObjDesc->BankField.BankObj));
  
          /*
           * Remember location in AML stream of the field unit
           * opcode and operands -- since the BankValue
           * operands must be evaluated.
           */
          SecondDesc = ObjDesc->Common.NextObject;
          SecondDesc->Extra.AmlStart = ACPI_CAST_PTR (ACPI_PARSE_OBJECT,
              Info->DataRegisterNode)->Named.Data;
          SecondDesc->Extra.AmlLength = ACPI_CAST_PTR (ACPI_PARSE_OBJECT,
              Info->DataRegisterNode)->Named.Length;
  
          break;
  
  
      case ACPI_TYPE_LOCAL_INDEX_FIELD:
  
          /* Get the Index and Data registers */
  
          ObjDesc->IndexField.IndexObj =
              AcpiNsGetAttachedObject (Info->RegisterNode);
          ObjDesc->IndexField.DataObj =
              AcpiNsGetAttachedObject (Info->DataRegisterNode);
  
          if (!ObjDesc->IndexField.DataObj || !ObjDesc->IndexField.IndexObj)
          {
              ACPI_ERROR ((AE_INFO, "Null Index Object during field prep"));
              AcpiUtDeleteObjectDesc (ObjDesc);
              return_ACPI_STATUS (AE_AML_INTERNAL);
          }
  
          /* An additional reference for the attached objects */
  
          AcpiUtAddReference (ObjDesc->IndexField.DataObj);
          AcpiUtAddReference (ObjDesc->IndexField.IndexObj);
  
          /*
           * April 2006: Changed to match MS behavior
           *
           * The value written to the Index register is the byte offset of the
           * target field in units of the granularity of the IndexField
           *
           * Previously, the value was calculated as an index in terms of the
           * width of the Data register, as below:
           *
           *      ObjDesc->IndexField.Value = (UINT32)
           *          (Info->FieldBitPosition / ACPI_MUL_8 (
           *              ObjDesc->Field.AccessByteWidth));
           *
           * February 2006: Tried value as a byte offset:
           *      ObjDesc->IndexField.Value = (UINT32)
           *          ACPI_DIV_8 (Info->FieldBitPosition);
           */
          ObjDesc->IndexField.Value = (UINT32) ACPI_ROUND_DOWN (
              ACPI_DIV_8 (Info->FieldBitPosition),
              ObjDesc->IndexField.AccessByteWidth);
  
          ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
              "IndexField: BitOff %X, Off %X, Value %X, Gran %X, Index %p, Data %p\n",
              ObjDesc->IndexField.StartFieldBitOffset,
              ObjDesc->IndexField.BaseByteOffset,
              ObjDesc->IndexField.Value,
              ObjDesc->Field.AccessByteWidth,
              ObjDesc->IndexField.IndexObj,
              ObjDesc->IndexField.DataObj));
          break;
  
      default:
          /* No other types should get here */
          break;
      }
  
      /*
       * Store the constructed descriptor (ObjDesc) into the parent Node,
       * preserving the current type of that NamedObj.
       */
      Status = AcpiNsAttachObject (Info->FieldNode, ObjDesc,
                  AcpiNsGetType (Info->FieldNode));
  
      ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "Set NamedObj %p [%4.4s], ObjDesc %p\n",
          Info->FieldNode, AcpiUtGetNodeName (Info->FieldNode), ObjDesc));
  
      /* Remove local reference to the object */
  
      AcpiUtRemoveReference (ObjDesc);
      return_ACPI_STATUS (Status);
  }
  
  