dsobject.c

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/******************************************************************************
 *
 * Module Name: dsobject - Dispatcher object management routines
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2012, 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 <acpi/acpi.h>
#include "accommon.h"
#include "acparser.h"
#include "amlcode.h"
#include "acdispat.h"
#include "acnamesp.h"
#include "acinterp.h"

#define _COMPONENT          ACPI_DISPATCHER
ACPI_MODULE_NAME("dsobject")

/* Local prototypes */
static acpi_status
acpi_ds_build_internal_object(struct acpi_walk_state *walk_state,
                  union acpi_parse_object *op,
                  union acpi_operand_object **obj_desc_ptr);

#ifndef ACPI_NO_METHOD_EXECUTION
/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_build_internal_object
 *
 * PARAMETERS:  walk_state      - Current walk state
 *              op              - Parser object to be translated
 *              obj_desc_ptr    - Where the ACPI internal object is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Translate a parser Op object to the equivalent namespace object
 *              Simple objects are any objects other than a package object!
 *
 ******************************************************************************/

static acpi_status
acpi_ds_build_internal_object(struct acpi_walk_state *walk_state,
                  union acpi_parse_object *op,
                  union acpi_operand_object **obj_desc_ptr)
{
    union acpi_operand_object *obj_desc;
    acpi_status status;
    acpi_object_type type;

    ACPI_FUNCTION_TRACE(ds_build_internal_object);

    *obj_desc_ptr = NULL;
    if (op->common.aml_opcode == AML_INT_NAMEPATH_OP) {
        /*
         * This is a named object reference. If this name was
         * previously looked up in the namespace, it was stored in this op.
         * Otherwise, go ahead and look it up now
         */
        if (!op->common.node) {
            status = acpi_ns_lookup(walk_state->scope_info,
                        op->common.value.string,
                        ACPI_TYPE_ANY,
                        ACPI_IMODE_EXECUTE,
                        ACPI_NS_SEARCH_PARENT |
                        ACPI_NS_DONT_OPEN_SCOPE, NULL,
                        ACPI_CAST_INDIRECT_PTR(struct
                                       acpi_namespace_node,
                                       &(op->
                                     common.
                                     node)));
            if (ACPI_FAILURE(status)) {

                /* Check if we are resolving a named reference within a package */

                if ((status == AE_NOT_FOUND)
                    && (acpi_gbl_enable_interpreter_slack)
                    &&
                    ((op->common.parent->common.aml_opcode ==
                      AML_PACKAGE_OP)
                     || (op->common.parent->common.aml_opcode ==
                     AML_VAR_PACKAGE_OP))) {
                    /*
                     * We didn't find the target and we are populating elements
                     * of a package - ignore if slack enabled. Some ASL code
                     * contains dangling invalid references in packages and
                     * expects that no exception will be issued. Leave the
                     * element as a null element. It cannot be used, but it
                     * can be overwritten by subsequent ASL code - this is
                     * typically the case.
                     */
                    ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                              "Ignoring unresolved reference in package [%4.4s]\n",
                              walk_state->
                              scope_info->scope.
                              node->name.ascii));

                    return_ACPI_STATUS(AE_OK);
                } else {
                    ACPI_ERROR_NAMESPACE(op->common.value.
                                 string, status);
                }

                return_ACPI_STATUS(status);
            }
        }

        /* Special object resolution for elements of a package */

        if ((op->common.parent->common.aml_opcode == AML_PACKAGE_OP) ||
            (op->common.parent->common.aml_opcode ==
             AML_VAR_PACKAGE_OP)) {
            /*
             * Attempt to resolve the node to a value before we insert it into
             * the package. If this is a reference to a common data type,
             * resolve it immediately. According to the ACPI spec, package
             * elements can only be "data objects" or method references.
             * Attempt to resolve to an Integer, Buffer, String or Package.
             * If cannot, return the named reference (for things like Devices,
             * Methods, etc.) Buffer Fields and Fields will resolve to simple
             * objects (int/buf/str/pkg).
             *
             * NOTE: References to things like Devices, Methods, Mutexes, etc.
             * will remain as named references. This behavior is not described
             * in the ACPI spec, but it appears to be an oversight.
             */
            obj_desc =
                ACPI_CAST_PTR(union acpi_operand_object,
                      op->common.node);

            status =
                acpi_ex_resolve_node_to_value(ACPI_CAST_INDIRECT_PTR
                              (struct
                               acpi_namespace_node,
                               &obj_desc),
                              walk_state);
            if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
            }

            /*
             * Special handling for Alias objects. We need to setup the type
             * and the Op->Common.Node to point to the Alias target. Note,
             * Alias has at most one level of indirection internally.
             */
            type = op->common.node->type;
            if (type == ACPI_TYPE_LOCAL_ALIAS) {
                type = obj_desc->common.type;
                op->common.node =
                    ACPI_CAST_PTR(struct acpi_namespace_node,
                          op->common.node->object);
            }

            switch (type) {
                /*
                 * For these types, we need the actual node, not the subobject.
                 * However, the subobject did not get an extra reference count above.
                 *
                 * TBD: should ex_resolve_node_to_value be changed to fix this?
                 */
            case ACPI_TYPE_DEVICE:
            case ACPI_TYPE_THERMAL:

                acpi_ut_add_reference(op->common.node->object);

                /*lint -fallthrough */
                /*
                 * For these types, we need the actual node, not the subobject.
                 * The subobject got an extra reference count in ex_resolve_node_to_value.
                 */
            case ACPI_TYPE_MUTEX:
            case ACPI_TYPE_METHOD:
            case ACPI_TYPE_POWER:
            case ACPI_TYPE_PROCESSOR:
            case ACPI_TYPE_EVENT:
            case ACPI_TYPE_REGION:

                /* We will create a reference object for these types below */
                break;

            default:
                /*
                 * All other types - the node was resolved to an actual
                 * object, we are done.
                 */
                goto exit;
            }
        }
    }

    /* Create and init a new internal ACPI object */

    obj_desc = acpi_ut_create_internal_object((acpi_ps_get_opcode_info
                           (op->common.aml_opcode))->
                          object_type);
    if (!obj_desc) {
        return_ACPI_STATUS(AE_NO_MEMORY);
    }

    status =
        acpi_ds_init_object_from_op(walk_state, op, op->common.aml_opcode,
                    &obj_desc);
    if (ACPI_FAILURE(status)) {
        acpi_ut_remove_reference(obj_desc);
        return_ACPI_STATUS(status);
    }

      exit:
    *obj_desc_ptr = obj_desc;
    return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_build_internal_buffer_obj
 *
 * PARAMETERS:  walk_state      - Current walk state
 *              op              - Parser object to be translated
 *              buffer_length   - Length of the buffer
 *              obj_desc_ptr    - Where the ACPI internal object is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Translate a parser Op package object to the equivalent
 *              namespace object
 *
 ******************************************************************************/

acpi_status
acpi_ds_build_internal_buffer_obj(struct acpi_walk_state *walk_state,
                  union acpi_parse_object *op,
                  u32 buffer_length,
                  union acpi_operand_object **obj_desc_ptr)
{
    union acpi_parse_object *arg;
    union acpi_operand_object *obj_desc;
    union acpi_parse_object *byte_list;
    u32 byte_list_length = 0;

    ACPI_FUNCTION_TRACE(ds_build_internal_buffer_obj);

    /*
     * If we are evaluating a Named buffer object "Name (xxxx, Buffer)".
     * The buffer object already exists (from the NS node), otherwise it must
     * be created.
     */
    obj_desc = *obj_desc_ptr;
    if (!obj_desc) {

        /* Create a new buffer object */

        obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_BUFFER);
        *obj_desc_ptr = obj_desc;
        if (!obj_desc) {
            return_ACPI_STATUS(AE_NO_MEMORY);
        }
    }

    /*
     * Second arg is the buffer data (optional) byte_list can be either
     * individual bytes or a string initializer.  In either case, a
     * byte_list appears in the AML.
     */
    arg = op->common.value.arg; /* skip first arg */

    byte_list = arg->named.next;
    if (byte_list) {
        if (byte_list->common.aml_opcode != AML_INT_BYTELIST_OP) {
            ACPI_ERROR((AE_INFO,
                    "Expecting bytelist, found AML opcode 0x%X in op %p",
                    byte_list->common.aml_opcode, byte_list));

            acpi_ut_remove_reference(obj_desc);
            return (AE_TYPE);
        }

        byte_list_length = (u32) byte_list->common.value.integer;
    }

    /*
     * The buffer length (number of bytes) will be the larger of:
     * 1) The specified buffer length and
     * 2) The length of the initializer byte list
     */
    obj_desc->buffer.length = buffer_length;
    if (byte_list_length > buffer_length) {
        obj_desc->buffer.length = byte_list_length;
    }

    /* Allocate the buffer */

    if (obj_desc->buffer.length == 0) {
        obj_desc->buffer.pointer = NULL;
        ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
                  "Buffer defined with zero length in AML, creating\n"));
    } else {
        obj_desc->buffer.pointer =
            ACPI_ALLOCATE_ZEROED(obj_desc->buffer.length);
        if (!obj_desc->buffer.pointer) {
            acpi_ut_delete_object_desc(obj_desc);
            return_ACPI_STATUS(AE_NO_MEMORY);
        }

        /* Initialize buffer from the byte_list (if present) */

        if (byte_list) {
            ACPI_MEMCPY(obj_desc->buffer.pointer,
                    byte_list->named.data, byte_list_length);
        }
    }

    obj_desc->buffer.flags |= AOPOBJ_DATA_VALID;
    op->common.node = ACPI_CAST_PTR(struct acpi_namespace_node, obj_desc);
    return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_build_internal_package_obj
 *
 * PARAMETERS:  walk_state      - Current walk state
 *              op              - Parser object to be translated
 *              element_count   - Number of elements in the package - this is
 *                                the num_elements argument to Package()
 *              obj_desc_ptr    - Where the ACPI internal object is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Translate a parser Op package object to the equivalent
 *              namespace object
 *
 * NOTE: The number of elements in the package will be always be the num_elements
 * count, regardless of the number of elements in the package list. If
 * num_elements is smaller, only that many package list elements are used.
 * if num_elements is larger, the Package object is padded out with
 * objects of type Uninitialized (as per ACPI spec.)
 *
 * Even though the ASL compilers do not allow num_elements to be smaller
 * than the Package list length (for the fixed length package opcode), some
 * BIOS code modifies the AML on the fly to adjust the num_elements, and
 * this code compensates for that. This also provides compatibility with
 * other AML interpreters.
 *
 ******************************************************************************/

acpi_status
acpi_ds_build_internal_package_obj(struct acpi_walk_state *walk_state,
                   union acpi_parse_object *op,
                   u32 element_count,
                   union acpi_operand_object **obj_desc_ptr)
{
    union acpi_parse_object *arg;
    union acpi_parse_object *parent;
    union acpi_operand_object *obj_desc = NULL;
    acpi_status status = AE_OK;
    unsigned i;
    u16 index;
    u16 reference_count;

    ACPI_FUNCTION_TRACE(ds_build_internal_package_obj);

    /* Find the parent of a possibly nested package */

    parent = op->common.parent;
    while ((parent->common.aml_opcode == AML_PACKAGE_OP) ||
           (parent->common.aml_opcode == AML_VAR_PACKAGE_OP)) {
        parent = parent->common.parent;
    }

    /*
     * If we are evaluating a Named package object "Name (xxxx, Package)",
     * the package object already exists, otherwise it must be created.
     */
    obj_desc = *obj_desc_ptr;
    if (!obj_desc) {
        obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_PACKAGE);
        *obj_desc_ptr = obj_desc;
        if (!obj_desc) {
            return_ACPI_STATUS(AE_NO_MEMORY);
        }

        obj_desc->package.node = parent->common.node;
    }

    /*
     * Allocate the element array (array of pointers to the individual
     * objects) based on the num_elements parameter. Add an extra pointer slot
     * so that the list is always null terminated.
     */
    obj_desc->package.elements = ACPI_ALLOCATE_ZEROED(((acpi_size)
                               element_count +
                               1) * sizeof(void *));

    if (!obj_desc->package.elements) {
        acpi_ut_delete_object_desc(obj_desc);
        return_ACPI_STATUS(AE_NO_MEMORY);
    }

    obj_desc->package.count = element_count;

    /*
     * Initialize the elements of the package, up to the num_elements count.
     * Package is automatically padded with uninitialized (NULL) elements
     * if num_elements is greater than the package list length. Likewise,
     * Package is truncated if num_elements is less than the list length.
     */
    arg = op->common.value.arg;
    arg = arg->common.next;
    for (i = 0; arg && (i < element_count); i++) {
        if (arg->common.aml_opcode == AML_INT_RETURN_VALUE_OP) {
            if (arg->common.node->type == ACPI_TYPE_METHOD) {
                /*
                 * A method reference "looks" to the parser to be a method
                 * invocation, so we special case it here
                 */
                arg->common.aml_opcode = AML_INT_NAMEPATH_OP;
                status =
                    acpi_ds_build_internal_object(walk_state,
                                  arg,
                                  &obj_desc->
                                  package.
                                  elements[i]);
            } else {
                /* This package element is already built, just get it */

                obj_desc->package.elements[i] =
                    ACPI_CAST_PTR(union acpi_operand_object,
                          arg->common.node);
            }
        } else {
            status = acpi_ds_build_internal_object(walk_state, arg,
                                   &obj_desc->
                                   package.
                                   elements[i]);
        }

        if (*obj_desc_ptr) {

            /* Existing package, get existing reference count */

            reference_count =
                (*obj_desc_ptr)->common.reference_count;
            if (reference_count > 1) {

                /* Make new element ref count match original ref count */

                for (index = 0; index < (reference_count - 1);
                     index++) {
                    acpi_ut_add_reference((obj_desc->
                                   package.
                                   elements[i]));
                }
            }
        }

        arg = arg->common.next;
    }

    /* Check for match between num_elements and actual length of package_list */

    if (arg) {
        /*
         * num_elements was exhausted, but there are remaining elements in the
         * package_list. Truncate the package to num_elements.
         *
         * Note: technically, this is an error, from ACPI spec: "It is an error
         * for NumElements to be less than the number of elements in the
         * PackageList". However, we just print a message and
         * no exception is returned. This provides Windows compatibility. Some
         * BIOSs will alter the num_elements on the fly, creating this type
         * of ill-formed package object.
         */
        while (arg) {
            /*
             * We must delete any package elements that were created earlier
             * and are not going to be used because of the package truncation.
             */
            if (arg->common.node) {
                acpi_ut_remove_reference(ACPI_CAST_PTR
                             (union
                              acpi_operand_object,
                              arg->common.node));
                arg->common.node = NULL;
            }

            /* Find out how many elements there really are */

            i++;
            arg = arg->common.next;
        }

        ACPI_INFO((AE_INFO,
               "Actual Package length (%u) is larger than NumElements field (%u), truncated\n",
               i, element_count));
    } else if (i < element_count) {
        /*
         * Arg list (elements) was exhausted, but we did not reach num_elements count.
         * Note: this is not an error, the package is padded out with NULLs.
         */
        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                  "Package List length (%u) smaller than NumElements count (%u), padded with null elements\n",
                  i, element_count));
    }

    obj_desc->package.flags |= AOPOBJ_DATA_VALID;
    op->common.node = ACPI_CAST_PTR(struct acpi_namespace_node, obj_desc);
    return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_create_node
 *
 * PARAMETERS:  walk_state      - Current walk state
 *              node            - NS Node to be initialized
 *              op              - Parser object to be translated
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Create the object to be associated with a namespace node
 *
 ******************************************************************************/

acpi_status
acpi_ds_create_node(struct acpi_walk_state *walk_state,
            struct acpi_namespace_node *node,
            union acpi_parse_object *op)
{
    acpi_status status;
    union acpi_operand_object *obj_desc;

    ACPI_FUNCTION_TRACE_PTR(ds_create_node, op);

    /*
     * Because of the execution pass through the non-control-method
     * parts of the table, we can arrive here twice.  Only init
     * the named object node the first time through
     */
    if (acpi_ns_get_attached_object(node)) {
        return_ACPI_STATUS(AE_OK);
    }

    if (!op->common.value.arg) {

        /* No arguments, there is nothing to do */

        return_ACPI_STATUS(AE_OK);
    }

    /* Build an internal object for the argument(s) */

    status = acpi_ds_build_internal_object(walk_state, op->common.value.arg,
                           &obj_desc);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    /* Re-type the object according to its argument */

    node->type = obj_desc->common.type;

    /* Attach obj to node */

    status = acpi_ns_attach_object(node, obj_desc, node->type);

    /* Remove local reference to the object */

    acpi_ut_remove_reference(obj_desc);
    return_ACPI_STATUS(status);
}

#endif              /* ACPI_NO_METHOD_EXECUTION */

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_init_object_from_op
 *
 * PARAMETERS:  walk_state      - Current walk state
 *              op              - Parser op used to init the internal object
 *              opcode          - AML opcode associated with the object
 *              ret_obj_desc    - Namespace object to be initialized
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Initialize a namespace object from a parser Op and its
 *              associated arguments.  The namespace object is a more compact
 *              representation of the Op and its arguments.
 *
 ******************************************************************************/

acpi_status
acpi_ds_init_object_from_op(struct acpi_walk_state *walk_state,
                union acpi_parse_object *op,
                u16 opcode,
                union acpi_operand_object **ret_obj_desc)
{
    const struct acpi_opcode_info *op_info;
    union acpi_operand_object *obj_desc;
    acpi_status status = AE_OK;

    ACPI_FUNCTION_TRACE(ds_init_object_from_op);

    obj_desc = *ret_obj_desc;
    op_info = acpi_ps_get_opcode_info(opcode);
    if (op_info->class == AML_CLASS_UNKNOWN) {

        /* Unknown opcode */

        return_ACPI_STATUS(AE_TYPE);
    }

    /* Perform per-object initialization */

    switch (obj_desc->common.type) {
    case ACPI_TYPE_BUFFER:

        /*
         * Defer evaluation of Buffer term_arg operand
         */
        obj_desc->buffer.node =
            ACPI_CAST_PTR(struct acpi_namespace_node,
                  walk_state->operands[0]);
        obj_desc->buffer.aml_start = op->named.data;
        obj_desc->buffer.aml_length = op->named.length;
        break;

    case ACPI_TYPE_PACKAGE:

        /*
         * Defer evaluation of Package term_arg operand
         */
        obj_desc->package.node =
            ACPI_CAST_PTR(struct acpi_namespace_node,
                  walk_state->operands[0]);
        obj_desc->package.aml_start = op->named.data;
        obj_desc->package.aml_length = op->named.length;
        break;

    case ACPI_TYPE_INTEGER:

        switch (op_info->type) {
        case AML_TYPE_CONSTANT:
            /*
             * Resolve AML Constants here - AND ONLY HERE!
             * All constants are integers.
             * We mark the integer with a flag that indicates that it started
             * life as a constant -- so that stores to constants will perform
             * as expected (noop). zero_op is used as a placeholder for optional
             * target operands.
             */
            obj_desc->common.flags = AOPOBJ_AML_CONSTANT;

            switch (opcode) {
            case AML_ZERO_OP:

                obj_desc->integer.value = 0;
                break;

            case AML_ONE_OP:

                obj_desc->integer.value = 1;
                break;

            case AML_ONES_OP:

                obj_desc->integer.value = ACPI_UINT64_MAX;

                /* Truncate value if we are executing from a 32-bit ACPI table */

#ifndef ACPI_NO_METHOD_EXECUTION
                acpi_ex_truncate_for32bit_table(obj_desc);
#endif
                break;

            case AML_REVISION_OP:

                obj_desc->integer.value = ACPI_CA_VERSION;
                break;

            default:

                ACPI_ERROR((AE_INFO,
                        "Unknown constant opcode 0x%X",
                        opcode));
                status = AE_AML_OPERAND_TYPE;
                break;
            }
            break;

        case AML_TYPE_LITERAL:

            obj_desc->integer.value = op->common.value.integer;
#ifndef ACPI_NO_METHOD_EXECUTION
            acpi_ex_truncate_for32bit_table(obj_desc);
#endif
            break;

        default:
            ACPI_ERROR((AE_INFO, "Unknown Integer type 0x%X",
                    op_info->type));
            status = AE_AML_OPERAND_TYPE;
            break;
        }
        break;

    case ACPI_TYPE_STRING:

        obj_desc->string.pointer = op->common.value.string;
        obj_desc->string.length =
            (u32) ACPI_STRLEN(op->common.value.string);

        /*
         * The string is contained in the ACPI table, don't ever try
         * to delete it
         */
        obj_desc->common.flags |= AOPOBJ_STATIC_POINTER;
        break;

    case ACPI_TYPE_METHOD:
        break;

    case ACPI_TYPE_LOCAL_REFERENCE:

        switch (op_info->type) {
        case AML_TYPE_LOCAL_VARIABLE:

            /* Local ID (0-7) is (AML opcode - base AML_LOCAL_OP) */

            obj_desc->reference.value =
                ((u32)opcode) - AML_LOCAL_OP;
            obj_desc->reference.class = ACPI_REFCLASS_LOCAL;

#ifndef ACPI_NO_METHOD_EXECUTION
            status =
                acpi_ds_method_data_get_node(ACPI_REFCLASS_LOCAL,
                             obj_desc->reference.
                             value, walk_state,
                             ACPI_CAST_INDIRECT_PTR
                             (struct
                              acpi_namespace_node,
                              &obj_desc->reference.
                              object));
#endif
            break;

        case AML_TYPE_METHOD_ARGUMENT:

            /* Arg ID (0-6) is (AML opcode - base AML_ARG_OP) */

            obj_desc->reference.value = ((u32)opcode) - AML_ARG_OP;
            obj_desc->reference.class = ACPI_REFCLASS_ARG;

#ifndef ACPI_NO_METHOD_EXECUTION
            status = acpi_ds_method_data_get_node(ACPI_REFCLASS_ARG,
                                  obj_desc->
                                  reference.value,
                                  walk_state,
                                  ACPI_CAST_INDIRECT_PTR
                                  (struct
                                   acpi_namespace_node,
                                   &obj_desc->
                                   reference.
                                   object));
#endif
            break;

        default:    /* Object name or Debug object */

            switch (op->common.aml_opcode) {
            case AML_INT_NAMEPATH_OP:

                /* Node was saved in Op */

                obj_desc->reference.node = op->common.node;
                obj_desc->reference.object =
                    op->common.node->object;
                obj_desc->reference.class = ACPI_REFCLASS_NAME;
                break;

            case AML_DEBUG_OP:

                obj_desc->reference.class = ACPI_REFCLASS_DEBUG;
                break;

            default:

                ACPI_ERROR((AE_INFO,
                        "Unimplemented reference type for AML opcode: 0x%4.4X",
                        opcode));
                return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
            }
            break;
        }
        break;

    default:

        ACPI_ERROR((AE_INFO, "Unimplemented data type: 0x%X",
                obj_desc->common.type));

        status = AE_AML_OPERAND_TYPE;
        break;
    }

    return_ACPI_STATUS(status);
}