Linux-2.6.33.2/drivers/acpi/acpica/psargs.c
/******************************************************************************
*
* Module Name: psargs - Parse AML opcode arguments
*
*****************************************************************************/
/*
* Copyright (C) 2000 - 2008, 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 "acnamesp.h"
#include "acdispat.h"
#define _COMPONENT ACPI_PARSER
ACPI_MODULE_NAME("psargs")
/* Local prototypes */
static u32
acpi_ps_get_next_package_length(struct acpi_parse_state *parser_state);
static union acpi_parse_object *acpi_ps_get_next_field(struct acpi_parse_state
*parser_state);
/*******************************************************************************
*
* FUNCTION: acpi_ps_get_next_package_length
*
* PARAMETERS: parser_state - Current parser state object
*
* RETURN: Decoded package length. On completion, the AML pointer points
* past the length byte or bytes.
*
* DESCRIPTION: Decode and return a package length field.
* Note: Largest package length is 28 bits, from ACPI specification
*
******************************************************************************/
static u32
acpi_ps_get_next_package_length(struct acpi_parse_state *parser_state)
{
u8 *aml = parser_state->aml;
u32 package_length = 0;
u32 byte_count;
u8 byte_zero_mask = 0x3F; /* Default [0:5] */
ACPI_FUNCTION_TRACE(ps_get_next_package_length);
/*
* Byte 0 bits [6:7] contain the number of additional bytes
* used to encode the package length, either 0,1,2, or 3
*/
byte_count = (aml[0] >> 6);
parser_state->aml += ((acpi_size) byte_count + 1);
/* Get bytes 3, 2, 1 as needed */
while (byte_count) {
/*
* Final bit positions for the package length bytes:
* Byte3->[20:27]
* Byte2->[12:19]
* Byte1->[04:11]
* Byte0->[00:03]
*/
package_length |= (aml[byte_count] << ((byte_count << 3) - 4));
byte_zero_mask = 0x0F; /* Use bits [0:3] of byte 0 */
byte_count--;
}
/* Byte 0 is a special case, either bits [0:3] or [0:5] are used */
package_length |= (aml[0] & byte_zero_mask);
return_UINT32(package_length);
}
/*******************************************************************************
*
* FUNCTION: acpi_ps_get_next_package_end
*
* PARAMETERS: parser_state - Current parser state object
*
* RETURN: Pointer to end-of-package +1
*
* DESCRIPTION: Get next package length and return a pointer past the end of
* the package. Consumes the package length field
*
******************************************************************************/
u8 *acpi_ps_get_next_package_end(struct acpi_parse_state *parser_state)
{
u8 *start = parser_state->aml;
u32 package_length;
ACPI_FUNCTION_TRACE(ps_get_next_package_end);
/* Function below updates parser_state->Aml */
package_length = acpi_ps_get_next_package_length(parser_state);
return_PTR(start + package_length); /* end of package */
}
/*******************************************************************************
*
* FUNCTION: acpi_ps_get_next_namestring
*
* PARAMETERS: parser_state - Current parser state object
*
* RETURN: Pointer to the start of the name string (pointer points into
* the AML.
*
* DESCRIPTION: Get next raw namestring within the AML stream. Handles all name
* prefix characters. Set parser state to point past the string.
* (Name is consumed from the AML.)
*
******************************************************************************/
char *acpi_ps_get_next_namestring(struct acpi_parse_state *parser_state)
{
u8 *start = parser_state->aml;
u8 *end = parser_state->aml;
ACPI_FUNCTION_TRACE(ps_get_next_namestring);
/* Point past any namestring prefix characters (backslash or carat) */
while (acpi_ps_is_prefix_char(*end)) {
end++;
}
/* Decode the path prefix character */
switch (*end) {
case 0:
/* null_name */
if (end == start) {
start = NULL;
}
end++;
break;
case AML_DUAL_NAME_PREFIX:
/* Two name segments */
end += 1 + (2 * ACPI_NAME_SIZE);
break;
case AML_MULTI_NAME_PREFIX_OP:
/* Multiple name segments, 4 chars each, count in next byte */
end += 2 + (*(end + 1) * ACPI_NAME_SIZE);
break;
default:
/* Single name segment */
end += ACPI_NAME_SIZE;
break;
}
parser_state->aml = end;
return_PTR((char *)start);
}
/*******************************************************************************
*
* FUNCTION: acpi_ps_get_next_namepath
*
* PARAMETERS: parser_state - Current parser state object
* Arg - Where the namepath will be stored
* arg_count - If the namepath points to a control method
* the method's argument is returned here.
* possible_method_call - Whether the namepath can possibly be the
* start of a method call
*
* RETURN: Status
*
* DESCRIPTION: Get next name (if method call, return # of required args).
* Names are looked up in the internal namespace to determine
* if the name represents a control method. If a method
* is found, the number of arguments to the method is returned.
* This information is critical for parsing to continue correctly.
*
******************************************************************************/
acpi_status
acpi_ps_get_next_namepath(struct acpi_walk_state *walk_state,
struct acpi_parse_state *parser_state,
union acpi_parse_object *arg, u8 possible_method_call)
{
acpi_status status;
char *path;
union acpi_parse_object *name_op;
union acpi_operand_object *method_desc;
struct acpi_namespace_node *node;
u8 *start = parser_state->aml;
ACPI_FUNCTION_TRACE(ps_get_next_namepath);
path = acpi_ps_get_next_namestring(parser_state);
acpi_ps_init_op(arg, AML_INT_NAMEPATH_OP);
/* Null path case is allowed, just exit */
if (!path) {
arg->common.value.name = path;
return_ACPI_STATUS(AE_OK);
}
/*
* Lookup the name in the internal namespace, starting with the current
* scope. We don't want to add anything new to the namespace here,
* however, so we use MODE_EXECUTE.
* Allow searching of the parent tree, but don't open a new scope -
* we just want to lookup the object (must be mode EXECUTE to perform
* the upsearch)
*/
status = acpi_ns_lookup(walk_state->scope_info, path,
ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE,
NULL, &node);
/*
* If this name is a control method invocation, we must
* setup the method call
*/
if (ACPI_SUCCESS(status) &&
possible_method_call && (node->type == ACPI_TYPE_METHOD)) {
if (walk_state->opcode == AML_UNLOAD_OP) {
/*
* acpi_ps_get_next_namestring has increased the AML pointer,
* so we need to restore the saved AML pointer for method call.
*/
walk_state->parser_state.aml = start;
walk_state->arg_count = 1;
acpi_ps_init_op(arg, AML_INT_METHODCALL_OP);
return_ACPI_STATUS(AE_OK);
}
/* This name is actually a control method invocation */
method_desc = acpi_ns_get_attached_object(node);
ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
"Control Method - %p Desc %p Path=%p\n", node,
method_desc, path));
name_op = acpi_ps_alloc_op(AML_INT_NAMEPATH_OP);
if (!name_op) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
/* Change Arg into a METHOD CALL and attach name to it */
acpi_ps_init_op(arg, AML_INT_METHODCALL_OP);
name_op->common.value.name = path;
/* Point METHODCALL/NAME to the METHOD Node */
name_op->common.node = node;
acpi_ps_append_arg(arg, name_op);
if (!method_desc) {
ACPI_ERROR((AE_INFO,
"Control Method %p has no attached object",
node));
return_ACPI_STATUS(AE_AML_INTERNAL);
}
ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
"Control Method - %p Args %X\n",
node, method_desc->method.param_count));
/* Get the number of arguments to expect */
walk_state->arg_count = method_desc->method.param_count;
return_ACPI_STATUS(AE_OK);
}
/*
* Special handling if the name was not found during the lookup -
* some not_found cases are allowed
*/
if (status == AE_NOT_FOUND) {
/* 1) not_found is ok during load pass 1/2 (allow forward references) */
if ((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) !=
ACPI_PARSE_EXECUTE) {
status = AE_OK;
}
/* 2) not_found during a cond_ref_of(x) is ok by definition */
else if (walk_state->op->common.aml_opcode ==
AML_COND_REF_OF_OP) {
status = AE_OK;
}
/*
* 3) not_found while building a Package is ok at this point, we
* may flag as an error later if slack mode is not enabled.
* (Some ASL code depends on allowing this behavior)
*/
else if ((arg->common.parent) &&
((arg->common.parent->common.aml_opcode ==
AML_PACKAGE_OP)
|| (arg->common.parent->common.aml_opcode ==
AML_VAR_PACKAGE_OP))) {
status = AE_OK;
}
}
/* Final exception check (may have been changed from code above) */
if (ACPI_FAILURE(status)) {
ACPI_ERROR_NAMESPACE(path, status);
if ((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) ==
ACPI_PARSE_EXECUTE) {
/* Report a control method execution error */
status = acpi_ds_method_error(status, walk_state);
}
}
/* Save the namepath */
arg->common.value.name = path;
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ps_get_next_simple_arg
*
* PARAMETERS: parser_state - Current parser state object
* arg_type - The argument type (AML_*_ARG)
* Arg - Where the argument is returned
*
* RETURN: None
*
* DESCRIPTION: Get the next simple argument (constant, string, or namestring)
*
******************************************************************************/
void
acpi_ps_get_next_simple_arg(struct acpi_parse_state *parser_state,
u32 arg_type, union acpi_parse_object *arg)
{
u32 length;
u16 opcode;
u8 *aml = parser_state->aml;
ACPI_FUNCTION_TRACE_U32(ps_get_next_simple_arg, arg_type);
switch (arg_type) {
case ARGP_BYTEDATA:
/* Get 1 byte from the AML stream */
opcode = AML_BYTE_OP;
arg->common.value.integer = (acpi_integer) * aml;
length = 1;
break;
case ARGP_WORDDATA:
/* Get 2 bytes from the AML stream */
opcode = AML_WORD_OP;
ACPI_MOVE_16_TO_64(&arg->common.value.integer, aml);
length = 2;
break;
case ARGP_DWORDDATA:
/* Get 4 bytes from the AML stream */
opcode = AML_DWORD_OP;
ACPI_MOVE_32_TO_64(&arg->common.value.integer, aml);
length = 4;
break;
case ARGP_QWORDDATA:
/* Get 8 bytes from the AML stream */
opcode = AML_QWORD_OP;
ACPI_MOVE_64_TO_64(&arg->common.value.integer, aml);
length = 8;
break;
case ARGP_CHARLIST:
/* Get a pointer to the string, point past the string */
opcode = AML_STRING_OP;
arg->common.value.string = ACPI_CAST_PTR(char, aml);
/* Find the null terminator */
length = 0;
while (aml[length]) {
length++;
}
length++;
break;
case ARGP_NAME:
case ARGP_NAMESTRING:
acpi_ps_init_op(arg, AML_INT_NAMEPATH_OP);
arg->common.value.name =
acpi_ps_get_next_namestring(parser_state);
return_VOID;
default:
ACPI_ERROR((AE_INFO, "Invalid ArgType %X", arg_type));
return_VOID;
}
acpi_ps_init_op(arg, opcode);
parser_state->aml += length;
return_VOID;
}
/*******************************************************************************
*
* FUNCTION: acpi_ps_get_next_field
*
* PARAMETERS: parser_state - Current parser state object
*
* RETURN: A newly allocated FIELD op
*
* DESCRIPTION: Get next field (named_field, reserved_field, or access_field)
*
******************************************************************************/
static union acpi_parse_object *acpi_ps_get_next_field(struct acpi_parse_state
*parser_state)
{
u32 aml_offset = (u32)
ACPI_PTR_DIFF(parser_state->aml,
parser_state->aml_start);
union acpi_parse_object *field;
u16 opcode;
u32 name;
ACPI_FUNCTION_TRACE(ps_get_next_field);
/* Determine field type */
switch (ACPI_GET8(parser_state->aml)) {
default:
opcode = AML_INT_NAMEDFIELD_OP;
break;
case 0x00:
opcode = AML_INT_RESERVEDFIELD_OP;
parser_state->aml++;
break;
case 0x01:
opcode = AML_INT_ACCESSFIELD_OP;
parser_state->aml++;
break;
}
/* Allocate a new field op */
field = acpi_ps_alloc_op(opcode);
if (!field) {
return_PTR(NULL);
}
field->common.aml_offset = aml_offset;
/* Decode the field type */
switch (opcode) {
case AML_INT_NAMEDFIELD_OP:
/* Get the 4-character name */
ACPI_MOVE_32_TO_32(&name, parser_state->aml);
acpi_ps_set_name(field, name);
parser_state->aml += ACPI_NAME_SIZE;
/* Get the length which is encoded as a package length */
field->common.value.size =
acpi_ps_get_next_package_length(parser_state);
break;
case AML_INT_RESERVEDFIELD_OP:
/* Get the length which is encoded as a package length */
field->common.value.size =
acpi_ps_get_next_package_length(parser_state);
break;
case AML_INT_ACCESSFIELD_OP:
/*
* Get access_type and access_attrib and merge into the field Op
* access_type is first operand, access_attribute is second
*/
field->common.value.integer =
(((u32) ACPI_GET8(parser_state->aml) << 8));
parser_state->aml++;
field->common.value.integer |= ACPI_GET8(parser_state->aml);
parser_state->aml++;
break;
default:
/* Opcode was set in previous switch */
break;
}
return_PTR(field);
}
/*******************************************************************************
*
* FUNCTION: acpi_ps_get_next_arg
*
* PARAMETERS: walk_state - Current state
* parser_state - Current parser state object
* arg_type - The argument type (AML_*_ARG)
* return_arg - Where the next arg is returned
*
* RETURN: Status, and an op object containing the next argument.
*
* DESCRIPTION: Get next argument (including complex list arguments that require
* pushing the parser stack)
*
******************************************************************************/
acpi_status
acpi_ps_get_next_arg(struct acpi_walk_state *walk_state,
struct acpi_parse_state *parser_state,
u32 arg_type, union acpi_parse_object **return_arg)
{
union acpi_parse_object *arg = NULL;
union acpi_parse_object *prev = NULL;
union acpi_parse_object *field;
u32 subop;
acpi_status status = AE_OK;
ACPI_FUNCTION_TRACE_PTR(ps_get_next_arg, parser_state);
switch (arg_type) {
case ARGP_BYTEDATA:
case ARGP_WORDDATA:
case ARGP_DWORDDATA:
case ARGP_CHARLIST:
case ARGP_NAME:
case ARGP_NAMESTRING:
/* Constants, strings, and namestrings are all the same size */
arg = acpi_ps_alloc_op(AML_BYTE_OP);
if (!arg) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
acpi_ps_get_next_simple_arg(parser_state, arg_type, arg);
break;
case ARGP_PKGLENGTH:
/* Package length, nothing returned */
parser_state->pkg_end =
acpi_ps_get_next_package_end(parser_state);
break;
case ARGP_FIELDLIST:
if (parser_state->aml < parser_state->pkg_end) {
/* Non-empty list */
while (parser_state->aml < parser_state->pkg_end) {
field = acpi_ps_get_next_field(parser_state);
if (!field) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
if (prev) {
prev->common.next = field;
} else {
arg = field;
}
prev = field;
}
/* Skip to End of byte data */
parser_state->aml = parser_state->pkg_end;
}
break;
case ARGP_BYTELIST:
if (parser_state->aml < parser_state->pkg_end) {
/* Non-empty list */
arg = acpi_ps_alloc_op(AML_INT_BYTELIST_OP);
if (!arg) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
/* Fill in bytelist data */
arg->common.value.size = (u32)
ACPI_PTR_DIFF(parser_state->pkg_end,
parser_state->aml);
arg->named.data = parser_state->aml;
/* Skip to End of byte data */
parser_state->aml = parser_state->pkg_end;
}
break;
case ARGP_TARGET:
case ARGP_SUPERNAME:
case ARGP_SIMPLENAME:
subop = acpi_ps_peek_opcode(parser_state);
if (subop == 0 ||
acpi_ps_is_leading_char(subop) ||
acpi_ps_is_prefix_char(subop)) {
/* null_name or name_string */
arg = acpi_ps_alloc_op(AML_INT_NAMEPATH_OP);
if (!arg) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
/* To support super_name arg of Unload */
if (walk_state->opcode == AML_UNLOAD_OP) {
status =
acpi_ps_get_next_namepath(walk_state,
parser_state, arg,
1);
/*
* If the super_name arg of Unload is a method call,
* we have restored the AML pointer, just free this Arg
*/
if (arg->common.aml_opcode ==
AML_INT_METHODCALL_OP) {
acpi_ps_free_op(arg);
arg = NULL;
}
} else {
status =
acpi_ps_get_next_namepath(walk_state,
parser_state, arg,
0);
}
} else {
/* Single complex argument, nothing returned */
walk_state->arg_count = 1;
}
break;
case ARGP_DATAOBJ:
case ARGP_TERMARG:
/* Single complex argument, nothing returned */
walk_state->arg_count = 1;
break;
case ARGP_DATAOBJLIST:
case ARGP_TERMLIST:
case ARGP_OBJLIST:
if (parser_state->aml < parser_state->pkg_end) {
/* Non-empty list of variable arguments, nothing returned */
walk_state->arg_count = ACPI_VAR_ARGS;
}
break;
default:
ACPI_ERROR((AE_INFO, "Invalid ArgType: %X", arg_type));
status = AE_AML_OPERAND_TYPE;
break;
}
*return_arg = arg;
return_ACPI_STATUS(status);
}