nsparse.c

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/******************************************************************************
 *
 * Module Name: nsparse - namespace interface to AML parser
 *
 *****************************************************************************/

/*
 * 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 "acnamesp.h"
#include "acparser.h"
#include "acdispat.h"
#include "actables.h"

#define _COMPONENT          ACPI_NAMESPACE
ACPI_MODULE_NAME("nsparse")

/*******************************************************************************
 *
 * FUNCTION:    ns_one_complete_parse
 *
 * PARAMETERS:  pass_number             - 1 or 2
 *              table_desc              - The table to be parsed.
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Perform one complete parse of an ACPI/AML table.
 *
 ******************************************************************************/
acpi_status
acpi_ns_one_complete_parse(u32 pass_number,
               u32 table_index,
               struct acpi_namespace_node *start_node)
{
    union acpi_parse_object *parse_root;
    acpi_status status;
       u32 aml_length;
    u8 *aml_start;
    struct acpi_walk_state *walk_state;
    struct acpi_table_header *table;
    acpi_owner_id owner_id;

    ACPI_FUNCTION_TRACE(ns_one_complete_parse);

    status = acpi_tb_get_owner_id(table_index, &owner_id);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    /* Create and init a Root Node */

    parse_root = acpi_ps_create_scope_op();
    if (!parse_root) {
        return_ACPI_STATUS(AE_NO_MEMORY);
    }

    /* Create and initialize a new walk state */

    walk_state = acpi_ds_create_walk_state(owner_id, NULL, NULL, NULL);
    if (!walk_state) {
        acpi_ps_free_op(parse_root);
        return_ACPI_STATUS(AE_NO_MEMORY);
    }

    status = acpi_get_table_by_index(table_index, &table);
    if (ACPI_FAILURE(status)) {
        acpi_ds_delete_walk_state(walk_state);
        acpi_ps_free_op(parse_root);
        return_ACPI_STATUS(status);
    }

    /* Table must consist of at least a complete header */

    if (table->length < sizeof(struct acpi_table_header)) {
        status = AE_BAD_HEADER;
    } else {
        aml_start = (u8 *) table + sizeof(struct acpi_table_header);
        aml_length = table->length - sizeof(struct acpi_table_header);
        status = acpi_ds_init_aml_walk(walk_state, parse_root, NULL,
                           aml_start, aml_length, NULL,
                           (u8) pass_number);
    }

    if (ACPI_FAILURE(status)) {
        acpi_ds_delete_walk_state(walk_state);
        goto cleanup;
    }

    /* start_node is the default location to load the table */

    if (start_node && start_node != acpi_gbl_root_node) {
        status =
            acpi_ds_scope_stack_push(start_node, ACPI_TYPE_METHOD,
                         walk_state);
        if (ACPI_FAILURE(status)) {
            acpi_ds_delete_walk_state(walk_state);
            goto cleanup;
        }
    }

    /* Parse the AML */

    ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "*PARSE* pass %u parse\n",
              pass_number));
    status = acpi_ps_parse_aml(walk_state);

      cleanup:
    acpi_ps_delete_parse_tree(parse_root);
    return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_parse_table
 *
 * PARAMETERS:  table_desc      - An ACPI table descriptor for table to parse
 *              start_node      - Where to enter the table into the namespace
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Parse AML within an ACPI table and return a tree of ops
 *
 ******************************************************************************/

acpi_status
acpi_ns_parse_table(u32 table_index, struct acpi_namespace_node *start_node)
{
    acpi_status status;

    ACPI_FUNCTION_TRACE(ns_parse_table);

    /*
     * AML Parse, pass 1
     *
     * In this pass, we load most of the namespace.  Control methods
     * are not parsed until later.  A parse tree is not created.  Instead,
     * each Parser Op subtree is deleted when it is finished.  This saves
     * a great deal of memory, and allows a small cache of parse objects
     * to service the entire parse.  The second pass of the parse then
     * performs another complete parse of the AML.
     */
    ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "**** Start pass 1\n"));
    status = acpi_ns_one_complete_parse(ACPI_IMODE_LOAD_PASS1,
                        table_index, start_node);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    /*
     * AML Parse, pass 2
     *
     * In this pass, we resolve forward references and other things
     * that could not be completed during the first pass.
     * Another complete parse of the AML is performed, but the
     * overhead of this is compensated for by the fact that the
     * parse objects are all cached.
     */
    ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "**** Start pass 2\n"));
    status = acpi_ns_one_complete_parse(ACPI_IMODE_LOAD_PASS2,
                        table_index, start_node);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    return_ACPI_STATUS(status);
}