Merge ACPICA 20130117.

1 files changed, 874 insertions, 0 deletions

diff --git a/sys/contrib/dev/acpica/compiler/aslxref.c b/sys/contrib/dev/acpica/compiler/aslxref.c
new file mode 100644
index 0000000..188c214
--- /dev/null
+++ b/sys/contrib/dev/acpica/compiler/aslxref.c
@@ -0,0 +1,874 @@
+/******************************************************************************
+ *
+ * Module Name: aslxref - Namespace cross-reference
+ *
+ *****************************************************************************/
+
+/*
+ * Copyright (C) 2000 - 2013, 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.
+ */
+
+
+#include <contrib/dev/acpica/compiler/aslcompiler.h>
+#include "aslcompiler.y.h"
+#include <contrib/dev/acpica/include/acparser.h>
+#include <contrib/dev/acpica/include/amlcode.h>
+#include <contrib/dev/acpica/include/acnamesp.h>
+#include <contrib/dev/acpica/include/acdispat.h>
+
+
+#define _COMPONENT          ACPI_COMPILER
+        ACPI_MODULE_NAME    ("aslxref")
+
+/* Local prototypes */
+
+static ACPI_STATUS
+XfNamespaceLocateBegin (
+    ACPI_PARSE_OBJECT       *Op,
+    UINT32                  Level,
+    void                    *Context);
+
+static ACPI_STATUS
+XfNamespaceLocateEnd (
+    ACPI_PARSE_OBJECT       *Op,
+    UINT32                  Level,
+    void                    *Context);
+
+static BOOLEAN
+XfObjectExists (
+    char                    *Name);
+
+static ACPI_STATUS
+XfCompareOneNamespaceObject (
+    ACPI_HANDLE             ObjHandle,
+    UINT32                  Level,
+    void                    *Context,
+    void                    **ReturnValue);
+
+static void
+XfCheckFieldRange (
+    ACPI_PARSE_OBJECT       *Op,
+    UINT32                  RegionBitLength,
+    UINT32                  FieldBitOffset,
+    UINT32                  FieldBitLength,
+    UINT32                  AccessBitWidth);
+
+
+/*******************************************************************************
+ *
+ * FUNCTION:    XfCrossReferenceNamespace
+ *
+ * PARAMETERS:  None
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Perform a cross reference check of the parse tree against the
+ *              namespace. Every named referenced within the parse tree
+ *              should be get resolved with a namespace lookup. If not, the
+ *              original reference in the ASL code is invalid -- i.e., refers
+ *              to a non-existent object.
+ *
+ * NOTE:  The ASL "External" operator causes the name to be inserted into the
+ *        namespace so that references to the external name will be resolved
+ *        correctly here.
+ *
+ ******************************************************************************/
+
+ACPI_STATUS
+XfCrossReferenceNamespace (
+    void)
+{
+    ACPI_WALK_STATE         *WalkState;
+
+
+    DbgPrint (ASL_DEBUG_OUTPUT, "\nCross referencing namespace\n\n");
+
+    /*
+     * Create a new walk state for use when looking up names
+     * within the namespace (Passed as context to the callbacks)
+     */
+    WalkState = AcpiDsCreateWalkState (0, NULL, NULL, NULL);
+    if (!WalkState)
+    {
+        return (AE_NO_MEMORY);
+    }
+
+    /* Walk the entire parse tree */
+
+    TrWalkParseTree (RootNode, ASL_WALK_VISIT_TWICE, XfNamespaceLocateBegin,
+                        XfNamespaceLocateEnd, WalkState);
+    return (AE_OK);
+}
+
+
+/*******************************************************************************
+ *
+ * FUNCTION:    XfObjectExists
+ *
+ * PARAMETERS:  Name            - 4 char ACPI name
+ *
+ * RETURN:      TRUE if name exists in namespace
+ *
+ * DESCRIPTION: Walk the namespace to find an object
+ *
+ ******************************************************************************/
+
+static BOOLEAN
+XfObjectExists (
+    char                    *Name)
+{
+    ACPI_STATUS             Status;
+
+
+    /* Walk entire namespace from the supplied root */
+
+    Status = AcpiNsWalkNamespace (ACPI_TYPE_ANY, ACPI_ROOT_OBJECT,
+                ACPI_UINT32_MAX, FALSE, XfCompareOneNamespaceObject, NULL,
+                Name, NULL);
+    if (Status == AE_CTRL_TRUE)
+    {
+        /* At least one instance of the name was found */
+
+        return (TRUE);
+    }
+
+    return (FALSE);
+}
+
+
+/*******************************************************************************
+ *
+ * FUNCTION:    XfCompareOneNamespaceObject
+ *
+ * PARAMETERS:  ACPI_WALK_CALLBACK
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Compare name of one object.
+ *
+ ******************************************************************************/
+
+static ACPI_STATUS
+XfCompareOneNamespaceObject (
+    ACPI_HANDLE             ObjHandle,
+    UINT32                  Level,
+    void                    *Context,
+    void                    **ReturnValue)
+{
+    ACPI_NAMESPACE_NODE     *Node = (ACPI_NAMESPACE_NODE *) ObjHandle;
+
+
+    /* Simply check the name */
+
+    if (*((UINT32 *) (Context)) == Node->Name.Integer)
+    {
+        /* Abort walk if we found one instance */
+
+        return (AE_CTRL_TRUE);
+    }
+
+    return (AE_OK);
+}
+
+
+/*******************************************************************************
+ *
+ * FUNCTION:    XfCheckFieldRange
+ *
+ * PARAMETERS:  RegionBitLength     - Length of entire parent region
+ *              FieldBitOffset      - Start of the field unit (within region)
+ *              FieldBitLength      - Entire length of field unit
+ *              AccessBitWidth      - Access width of the field unit
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Check one field unit to make sure it fits in the parent
+ *              op region.
+ *
+ * Note: AccessBitWidth must be either 8,16,32, or 64
+ *
+ ******************************************************************************/
+
+static void
+XfCheckFieldRange (
+    ACPI_PARSE_OBJECT       *Op,
+    UINT32                  RegionBitLength,
+    UINT32                  FieldBitOffset,
+    UINT32                  FieldBitLength,
+    UINT32                  AccessBitWidth)
+{
+    UINT32                  FieldEndBitOffset;
+
+
+    /*
+     * Check each field unit against the region size. The entire
+     * field unit (start offset plus length) must fit within the
+     * region.
+     */
+    FieldEndBitOffset = FieldBitOffset + FieldBitLength;
+
+    if (FieldEndBitOffset > RegionBitLength)
+    {
+        /* Field definition itself is beyond the end-of-region */
+
+        AslError (ASL_ERROR, ASL_MSG_FIELD_UNIT_OFFSET, Op, NULL);
+        return;
+    }
+
+    /*
+     * Now check that the field plus AccessWidth doesn't go beyond
+     * the end-of-region. Assumes AccessBitWidth is a power of 2
+     */
+    FieldEndBitOffset = ACPI_ROUND_UP (FieldEndBitOffset, AccessBitWidth);
+
+    if (FieldEndBitOffset > RegionBitLength)
+    {
+        /* Field definition combined with the access is beyond EOR */
+
+        AslError (ASL_ERROR, ASL_MSG_FIELD_UNIT_ACCESS_WIDTH, Op, NULL);
+    }
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    XfNamespaceLocateBegin
+ *
+ * PARAMETERS:  ASL_WALK_CALLBACK
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Descending callback used during cross-reference. For named
+ *              object references, attempt to locate the name in the
+ *              namespace.
+ *
+ * NOTE: ASL references to named fields within resource descriptors are
+ *       resolved to integer values here. Therefore, this step is an
+ *       important part of the code generation. We don't know that the
+ *       name refers to a resource descriptor until now.
+ *
+ ******************************************************************************/
+
+static ACPI_STATUS
+XfNamespaceLocateBegin (
+    ACPI_PARSE_OBJECT       *Op,
+    UINT32                  Level,
+    void                    *Context)
+{
+    ACPI_WALK_STATE         *WalkState = (ACPI_WALK_STATE *) Context;
+    ACPI_NAMESPACE_NODE     *Node;
+    ACPI_STATUS             Status;
+    ACPI_OBJECT_TYPE        ObjectType;
+    char                    *Path;
+    UINT8                   PassedArgs;
+    ACPI_PARSE_OBJECT       *NextOp;
+    ACPI_PARSE_OBJECT       *OwningOp;
+    ACPI_PARSE_OBJECT       *SpaceIdOp;
+    UINT32                  MinimumLength;
+    UINT32                  Offset;
+    UINT32                  FieldBitLength;
+    UINT32                  TagBitLength;
+    UINT8                   Message = 0;
+    const ACPI_OPCODE_INFO  *OpInfo;
+    UINT32                  Flags;
+
+
+    ACPI_FUNCTION_TRACE_PTR (XfNamespaceLocateBegin, Op);
+
+    /*
+     * If this node is the actual declaration of a name
+     * [such as the XXXX name in "Method (XXXX)"],
+     * we are not interested in it here. We only care about names that are
+     * references to other objects within the namespace and the parent objects
+     * of name declarations
+     */
+    if (Op->Asl.CompileFlags & NODE_IS_NAME_DECLARATION)
+    {
+        return (AE_OK);
+    }
+
+    /* We are only interested in opcodes that have an associated name */
+
+    OpInfo = AcpiPsGetOpcodeInfo (Op->Asl.AmlOpcode);
+
+    if ((!(OpInfo->Flags & AML_NAMED)) &&
+        (!(OpInfo->Flags & AML_CREATE)) &&
+        (Op->Asl.ParseOpcode != PARSEOP_NAMESTRING) &&
+        (Op->Asl.ParseOpcode != PARSEOP_NAMESEG)    &&
+        (Op->Asl.ParseOpcode != PARSEOP_METHODCALL))
+    {
+        return (AE_OK);
+    }
+
+    /*
+     * One special case: CondRefOf operator - we don't care if the name exists
+     * or not at this point, just ignore it, the point of the operator is to
+     * determine if the name exists at runtime.
+     */
+    if ((Op->Asl.Parent) &&
+        (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_CONDREFOF))
+    {
+        return (AE_OK);
+    }
+
+    /*
+     * We must enable the "search-to-root" for single NameSegs, but
+     * we have to be very careful about opening up scopes
+     */
+    Flags = ACPI_NS_SEARCH_PARENT;
+    if ((Op->Asl.ParseOpcode == PARSEOP_NAMESTRING) ||
+        (Op->Asl.ParseOpcode == PARSEOP_NAMESEG)    ||
+        (Op->Asl.ParseOpcode == PARSEOP_METHODCALL))
+    {
+        /*
+         * These are name references, do not push the scope stack
+         * for them.
+         */
+        Flags |= ACPI_NS_DONT_OPEN_SCOPE;
+    }
+
+    /* Get the NamePath from the appropriate place */
+
+    if (OpInfo->Flags & AML_NAMED)
+    {
+        /* For nearly all NAMED operators, the name reference is the first child */
+
+        Path = Op->Asl.Child->Asl.Value.String;
+        if (Op->Asl.AmlOpcode == AML_ALIAS_OP)
+        {
+            /*
+             * ALIAS is the only oddball opcode, the name declaration
+             * (alias name) is the second operand
+             */
+            Path = Op->Asl.Child->Asl.Next->Asl.Value.String;
+        }
+    }
+    else if (OpInfo->Flags & AML_CREATE)
+    {
+        /* Name must appear as the last parameter */
+
+        NextOp = Op->Asl.Child;
+        while (!(NextOp->Asl.CompileFlags & NODE_IS_NAME_DECLARATION))
+        {
+            NextOp = NextOp->Asl.Next;
+        }
+        Path = NextOp->Asl.Value.String;
+    }
+    else
+    {
+        Path = Op->Asl.Value.String;
+    }
+
+    ObjectType = AslMapNamedOpcodeToDataType (Op->Asl.AmlOpcode);
+    ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
+        "Type=%s\n", AcpiUtGetTypeName (ObjectType)));
+
+    /*
+     * Lookup the name in the namespace. Name must exist at this point, or it
+     * is an invalid reference.
+     *
+     * The namespace is also used as a lookup table for references to resource
+     * descriptors and the fields within them.
+     */
+    Gbl_NsLookupCount++;
+
+    Status = AcpiNsLookup (WalkState->ScopeInfo, Path, ObjectType,
+                ACPI_IMODE_EXECUTE, Flags, WalkState, &(Node));
+    if (ACPI_FAILURE (Status))
+    {
+        if (Status == AE_NOT_FOUND)
+        {
+            /*
+             * We didn't find the name reference by path -- we can qualify this
+             * a little better before we print an error message
+             */
+            if (strlen (Path) == ACPI_NAME_SIZE)
+            {
+                /* A simple, one-segment ACPI name */
+
+                if (XfObjectExists (Path))
+                {
+                    /*
+                     * There exists such a name, but we couldn't get to it
+                     * from this scope
+                     */
+                    AslError (ASL_ERROR, ASL_MSG_NOT_REACHABLE, Op,
+                        Op->Asl.ExternalName);
+                }
+                else
+                {
+                    /* The name doesn't exist, period */
+
+                    AslError (ASL_ERROR, ASL_MSG_NOT_EXIST,
+                        Op, Op->Asl.ExternalName);
+                }
+            }
+            else
+            {
+                /* Check for a fully qualified path */
+
+                if (Path[0] == AML_ROOT_PREFIX)
+                {
+                    /* Gave full path, the object does not exist */
+
+                    AslError (ASL_ERROR, ASL_MSG_NOT_EXIST, Op,
+                        Op->Asl.ExternalName);
+                }
+                else
+                {
+                    /*
+                     * We can't tell whether it doesn't exist or just
+                     * can't be reached.
+                     */
+                    AslError (ASL_ERROR, ASL_MSG_NOT_FOUND, Op,
+                        Op->Asl.ExternalName);
+                }
+            }
+
+            Status = AE_OK;
+        }
+        return (Status);
+    }
+
+    /* Check for a reference vs. name declaration */
+
+    if (!(OpInfo->Flags & AML_NAMED) &&
+        !(OpInfo->Flags & AML_CREATE))
+    {
+        /* This node has been referenced, mark it for reference check */
+
+        Node->Flags |= ANOBJ_IS_REFERENCED;
+    }
+
+    /* Attempt to optimize the NamePath */
+
+    OptOptimizeNamePath (Op, OpInfo->Flags, WalkState, Path, Node);
+
+    /*
+     * 1) Dereference an alias (A name reference that is an alias)
+     *    Aliases are not nested, the alias always points to the final object
+     */
+    if ((Op->Asl.ParseOpcode != PARSEOP_ALIAS) &&
+        (Node->Type == ACPI_TYPE_LOCAL_ALIAS))
+    {
+        /* This node points back to the original PARSEOP_ALIAS */
+
+        NextOp = Node->Op;
+
+        /* The first child is the alias target op */
+
+        NextOp = NextOp->Asl.Child;
+
+        /* That in turn points back to original target alias node */
+
+        if (NextOp->Asl.Node)
+        {
+            Node = NextOp->Asl.Node;
+        }
+
+        /* Else - forward reference to alias, will be resolved later */
+    }
+
+    /* 2) Check for a reference to a resource descriptor */
+
+    if ((Node->Type == ACPI_TYPE_LOCAL_RESOURCE_FIELD) ||
+        (Node->Type == ACPI_TYPE_LOCAL_RESOURCE))
+    {
+        /*
+         * This was a reference to a field within a resource descriptor.
+         * Extract the associated field offset (either a bit or byte
+         * offset depending on the field type) and change the named
+         * reference into an integer for AML code generation
+         */
+        Offset = Node->Value;
+        TagBitLength = Node->Length;
+
+        /*
+         * If a field is being created, generate the length (in bits) of
+         * the field. Note: Opcodes other than CreateXxxField and Index
+         * can come through here. For other opcodes, we just need to
+         * convert the resource tag reference to an integer offset.
+         */
+        switch (Op->Asl.Parent->Asl.AmlOpcode)
+        {
+        case AML_CREATE_FIELD_OP: /* Variable "Length" field, in bits */
+            /*
+             * We know the length operand is an integer constant because
+             * we know that it contains a reference to a resource
+             * descriptor tag.
+             */
+            FieldBitLength = (UINT32) Op->Asl.Next->Asl.Value.Integer;
+            break;
+
+        case AML_CREATE_BIT_FIELD_OP:
+            FieldBitLength = 1;
+            break;
+
+        case AML_CREATE_BYTE_FIELD_OP:
+        case AML_INDEX_OP:
+            FieldBitLength = 8;
+            break;
+
+        case AML_CREATE_WORD_FIELD_OP:
+            FieldBitLength = 16;
+            break;
+
+        case AML_CREATE_DWORD_FIELD_OP:
+            FieldBitLength = 32;
+            break;
+
+        case AML_CREATE_QWORD_FIELD_OP:
+            FieldBitLength = 64;
+            break;
+
+        default:
+            FieldBitLength = 0;
+            break;
+        }
+
+        /* Check the field length against the length of the resource tag */
+
+        if (FieldBitLength)
+        {
+            if (TagBitLength < FieldBitLength)
+            {
+                Message = ASL_MSG_TAG_SMALLER;
+            }
+            else if (TagBitLength > FieldBitLength)
+            {
+                Message = ASL_MSG_TAG_LARGER;
+            }
+
+            if (Message)
+            {
+                sprintf (MsgBuffer, "Size mismatch, Tag: %u bit%s, Field: %u bit%s",
+                    TagBitLength, (TagBitLength > 1) ? "s" : "",
+                    FieldBitLength, (FieldBitLength > 1) ? "s" : "");
+
+                AslError (ASL_WARNING, Message, Op, MsgBuffer);
+            }
+        }
+
+        /* Convert the BitOffset to a ByteOffset for certain opcodes */
+
+        switch (Op->Asl.Parent->Asl.AmlOpcode)
+        {
+        case AML_CREATE_BYTE_FIELD_OP:
+        case AML_CREATE_WORD_FIELD_OP:
+        case AML_CREATE_DWORD_FIELD_OP:
+        case AML_CREATE_QWORD_FIELD_OP:
+        case AML_INDEX_OP:
+
+            Offset = ACPI_DIV_8 (Offset);
+            break;
+
+        default:
+            break;
+        }
+
+        /* Now convert this node to an integer whose value is the field offset */
+
+        Op->Asl.AmlLength = 0;
+        Op->Asl.ParseOpcode = PARSEOP_INTEGER;
+        Op->Asl.Value.Integer = (UINT64) Offset;
+        Op->Asl.CompileFlags |= NODE_IS_RESOURCE_FIELD;
+
+        OpcGenerateAmlOpcode (Op);
+    }
+
+    /* 3) Check for a method invocation */
+
+    else if ((((Op->Asl.ParseOpcode == PARSEOP_NAMESTRING) || (Op->Asl.ParseOpcode == PARSEOP_NAMESEG)) &&
+                (Node->Type == ACPI_TYPE_METHOD) &&
+                (Op->Asl.Parent) &&
+                (Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_METHOD))   ||
+
+                (Op->Asl.ParseOpcode == PARSEOP_METHODCALL))
+    {
+
+        /*
+         * A reference to a method within one of these opcodes is not an
+         * invocation of the method, it is simply a reference to the method.
+         */
+        if ((Op->Asl.Parent) &&
+           ((Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_REFOF)      ||
+            (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_DEREFOF)    ||
+            (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_OBJECTTYPE)))
+        {
+            return (AE_OK);
+        }
+        /*
+         * There are two types of method invocation:
+         * 1) Invocation with arguments -- the parser recognizes this
+         *    as a METHODCALL.
+         * 2) Invocation with no arguments --the parser cannot determine that
+         *    this is a method invocation, therefore we have to figure it out
+         *    here.
+         */
+        if (Node->Type != ACPI_TYPE_METHOD)
+        {
+            sprintf (MsgBuffer, "%s is a %s",
+                    Op->Asl.ExternalName, AcpiUtGetTypeName (Node->Type));
+
+            AslError (ASL_ERROR, ASL_MSG_NOT_METHOD, Op, MsgBuffer);
+            return (AE_OK);
+        }
+
+        /* Save the method node in the caller's op */
+
+        Op->Asl.Node = Node;
+        if (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_CONDREFOF)
+        {
+            return (AE_OK);
+        }
+
+        /*
+         * This is a method invocation, with or without arguments.
+         * Count the number of arguments, each appears as a child
+         * under the parent node
+         */
+        Op->Asl.ParseOpcode = PARSEOP_METHODCALL;
+        UtSetParseOpName (Op);
+
+        PassedArgs = 0;
+        NextOp     = Op->Asl.Child;
+
+        while (NextOp)
+        {
+            PassedArgs++;
+            NextOp = NextOp->Asl.Next;
+        }
+
+        if (Node->Value != ASL_EXTERNAL_METHOD)
+        {
+            /*
+             * Check the parsed arguments with the number expected by the
+             * method declaration itself
+             */
+            if (PassedArgs != Node->Value)
+            {
+                sprintf (MsgBuffer, "%s requires %u", Op->Asl.ExternalName,
+                            Node->Value);
+
+                if (PassedArgs < Node->Value)
+                {
+                    AslError (ASL_ERROR, ASL_MSG_ARG_COUNT_LO, Op, MsgBuffer);
+                }
+                else
+                {
+                    AslError (ASL_ERROR, ASL_MSG_ARG_COUNT_HI, Op, MsgBuffer);
+                }
+            }
+        }
+    }
+
+    /* 4) Check for an ASL Field definition */
+
+    else if ((Op->Asl.Parent) &&
+            ((Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_FIELD)     ||
+             (Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_BANKFIELD)))
+    {
+        /*
+         * Offset checking for fields. If the parent operation region has a
+         * constant length (known at compile time), we can check fields
+         * defined in that region against the region length. This will catch
+         * fields and field units that cannot possibly fit within the region.
+         *
+         * Note: Index fields do not directly reference an operation region,
+         * thus they are not included in this check.
+         */
+        if (Op == Op->Asl.Parent->Asl.Child)
+        {
+            /*
+             * This is the first child of the field node, which is
+             * the name of the region. Get the parse node for the
+             * region -- which contains the length of the region.
+             */
+            OwningOp = Node->Op;
+            Op->Asl.Parent->Asl.ExtraValue =
+                ACPI_MUL_8 ((UINT32) OwningOp->Asl.Value.Integer);
+
+            /* Examine the field access width */
+
+            switch ((UINT8) Op->Asl.Parent->Asl.Value.Integer)
+            {
+            case AML_FIELD_ACCESS_ANY:
+            case AML_FIELD_ACCESS_BYTE:
+            case AML_FIELD_ACCESS_BUFFER:
+            default:
+                MinimumLength = 1;
+                break;
+
+            case AML_FIELD_ACCESS_WORD:
+                MinimumLength = 2;
+                break;
+
+            case AML_FIELD_ACCESS_DWORD:
+                MinimumLength = 4;
+                break;
+
+            case AML_FIELD_ACCESS_QWORD:
+                MinimumLength = 8;
+                break;
+            }
+
+            /*
+             * Is the region at least as big as the access width?
+             * Note: DataTableRegions have 0 length
+             */
+            if (((UINT32) OwningOp->Asl.Value.Integer) &&
+                ((UINT32) OwningOp->Asl.Value.Integer < MinimumLength))
+            {
+                AslError (ASL_ERROR, ASL_MSG_FIELD_ACCESS_WIDTH, Op, NULL);
+            }
+
+            /*
+             * Check EC/CMOS/SMBUS fields to make sure that the correct
+             * access type is used (BYTE for EC/CMOS, BUFFER for SMBUS)
+             */
+            SpaceIdOp = OwningOp->Asl.Child->Asl.Next;
+            switch ((UINT32) SpaceIdOp->Asl.Value.Integer)
+            {
+            case ACPI_ADR_SPACE_EC:
+            case ACPI_ADR_SPACE_CMOS:
+            case ACPI_ADR_SPACE_GPIO:
+
+                if ((UINT8) Op->Asl.Parent->Asl.Value.Integer != AML_FIELD_ACCESS_BYTE)
+                {
+                    AslError (ASL_ERROR, ASL_MSG_REGION_BYTE_ACCESS, Op, NULL);
+                }
+                break;
+
+            case ACPI_ADR_SPACE_SMBUS:
+            case ACPI_ADR_SPACE_IPMI:
+            case ACPI_ADR_SPACE_GSBUS:
+
+                if ((UINT8) Op->Asl.Parent->Asl.Value.Integer != AML_FIELD_ACCESS_BUFFER)
+                {
+                    AslError (ASL_ERROR, ASL_MSG_REGION_BUFFER_ACCESS, Op, NULL);
+                }
+                break;
+
+            default:
+
+                /* Nothing to do for other address spaces */
+                break;
+            }
+        }
+        else
+        {
+            /*
+             * This is one element of the field list. Check to make sure
+             * that it does not go beyond the end of the parent operation region.
+             *
+             * In the code below:
+             *    Op->Asl.Parent->Asl.ExtraValue      - Region Length (bits)
+             *    Op->Asl.ExtraValue                  - Field start offset (bits)
+             *    Op->Asl.Child->Asl.Value.Integer32  - Field length (bits)
+             *    Op->Asl.Child->Asl.ExtraValue       - Field access width (bits)
+             */
+            if (Op->Asl.Parent->Asl.ExtraValue && Op->Asl.Child)
+            {
+                XfCheckFieldRange (Op,
+                            Op->Asl.Parent->Asl.ExtraValue,
+                            Op->Asl.ExtraValue,
+                            (UINT32) Op->Asl.Child->Asl.Value.Integer,
+                            Op->Asl.Child->Asl.ExtraValue);
+            }
+        }
+    }
+
+    Op->Asl.Node = Node;
+    return (Status);
+}
+
+
+/*******************************************************************************
+ *
+ * FUNCTION:    XfNamespaceLocateEnd
+ *
+ * PARAMETERS:  ASL_WALK_CALLBACK
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Ascending callback used during cross reference. We only
+ *              need to worry about scope management here.
+ *
+ ******************************************************************************/
+
+static ACPI_STATUS
+XfNamespaceLocateEnd (
+    ACPI_PARSE_OBJECT       *Op,
+    UINT32                  Level,
+    void                    *Context)
+{
+    ACPI_WALK_STATE         *WalkState = (ACPI_WALK_STATE *) Context;
+    const ACPI_OPCODE_INFO  *OpInfo;
+
+
+    ACPI_FUNCTION_TRACE (XfNamespaceLocateEnd);
+
+
+    /* We are only interested in opcodes that have an associated name */
+
+    OpInfo = AcpiPsGetOpcodeInfo (Op->Asl.AmlOpcode);
+    if (!(OpInfo->Flags & AML_NAMED))
+    {
+        return (AE_OK);
+    }
+
+    /* Not interested in name references, we did not open a scope for them */
+
+    if ((Op->Asl.ParseOpcode == PARSEOP_NAMESTRING) ||
+        (Op->Asl.ParseOpcode == PARSEOP_NAMESEG)    ||
+        (Op->Asl.ParseOpcode == PARSEOP_METHODCALL))
+    {
+        return (AE_OK);
+    }
+
+    /* Pop the scope stack if necessary */
+
+    if (AcpiNsOpensScope (AslMapNamedOpcodeToDataType (Op->Asl.AmlOpcode)))
+    {
+
+        ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
+            "%s: Popping scope for Op %p\n",
+            AcpiUtGetTypeName (OpInfo->ObjectType), Op));
+
+        (void) AcpiDsScopeStackPop (WalkState);
+    }
+
+    return (AE_OK);
+}