path: root/drivers/acpi/acpica/psloop.c

/******************************************************************************
 *
 * Module Name: psloop - Main AML parse loop
 *
 *****************************************************************************/

/*
 * 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.
 */

/*
 * Parse the AML and build an operation tree as most interpreters, (such as
 * Perl) do. Parsing is done by hand rather than with a YACC generated parser
 * to tightly constrain stack and dynamic memory usage. Parsing is kept
 * flexible and the code fairly compact by parsing based on a list of AML
 * opcode templates in aml_op_info[].
 */

#include <acpi/acpi.h>
#include "accommon.h"
#include "acparser.h"
#include "acdispat.h"
#include "amlcode.h"

#define _COMPONENT          ACPI_PARSER
ACPI_MODULE_NAME("psloop")

static u32 acpi_gbl_depth = 0;

/* Local prototypes */

static acpi_status acpi_ps_get_aml_opcode(struct acpi_walk_state *walk_state);

static acpi_status
acpi_ps_build_named_op(struct acpi_walk_state *walk_state,
		       u8 * aml_op_start,
		       union acpi_parse_object *unnamed_op,
		       union acpi_parse_object **op);

static acpi_status
acpi_ps_create_op(struct acpi_walk_state *walk_state,
		  u8 * aml_op_start, union acpi_parse_object **new_op);

static acpi_status
acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
		      u8 * aml_op_start, union acpi_parse_object *op);

static acpi_status
acpi_ps_complete_op(struct acpi_walk_state *walk_state,
		    union acpi_parse_object **op, acpi_status status);

static acpi_status
acpi_ps_complete_final_op(struct acpi_walk_state *walk_state,
			  union acpi_parse_object *op, acpi_status status);

static void
acpi_ps_link_module_code(union acpi_parse_object *parent_op,
			 u8 *aml_start, u32 aml_length, acpi_owner_id owner_id);

/*******************************************************************************
 *
 * FUNCTION:    acpi_ps_get_aml_opcode
 *
 * PARAMETERS:  walk_state          - Current state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Extract the next AML opcode from the input stream.
 *
 ******************************************************************************/

static acpi_status acpi_ps_get_aml_opcode(struct acpi_walk_state *walk_state)
{

	ACPI_FUNCTION_TRACE_PTR(ps_get_aml_opcode, walk_state);

	walk_state->aml_offset =
	    (u32) ACPI_PTR_DIFF(walk_state->parser_state.aml,
				walk_state->parser_state.aml_start);
	walk_state->opcode = acpi_ps_peek_opcode(&(walk_state->parser_state));

	/*
	 * First cut to determine what we have found:
	 * 1) A valid AML opcode
	 * 2) A name string
	 * 3) An unknown/invalid opcode
	 */
	walk_state->op_info = acpi_ps_get_opcode_info(walk_state->opcode);

	switch (walk_state->op_info->class) {
	case AML_CLASS_ASCII:
	case AML_CLASS_PREFIX:
		/*
		 * Starts with a valid prefix or ASCII char, this is a name
		 * string. Convert the bare name string to a namepath.
		 */
		walk_state->opcode = AML_INT_NAMEPATH_OP;
		walk_state->arg_types = ARGP_NAMESTRING;
		break;

	case AML_CLASS_UNKNOWN:

		/* The opcode is unrecognized. Just skip unknown opcodes */

		ACPI_ERROR((AE_INFO,
			    "Found unknown opcode 0x%X at AML address %p offset 0x%X, ignoring",
			    walk_state->opcode, walk_state->parser_state.aml,
			    walk_state->aml_