linux/drivers/acpi/parser/psargs.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

747 lines
19 KiB
C

/******************************************************************************
*
* Module Name: psargs - Parse AML opcode arguments
*
*****************************************************************************/
/*
* Copyright (C) 2000 - 2005, R. Byron Moore
* 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 <acpi/acparser.h>
#include <acpi/amlcode.h>
#include <acpi/acnamesp.h>
#define _COMPONENT ACPI_PARSER
ACPI_MODULE_NAME ("psargs")
/*******************************************************************************
*
* 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
*
******************************************************************************/
u32
acpi_ps_get_next_package_length (
struct acpi_parse_state *parser_state)
{
u32 encoded_length;
u32 length = 0;
ACPI_FUNCTION_TRACE ("ps_get_next_package_length");
encoded_length = (u32) ACPI_GET8 (parser_state->aml);
parser_state->aml++;
switch (encoded_length >> 6) /* bits 6-7 contain encoding scheme */ {
case 0: /* 1-byte encoding (bits 0-5) */
length = (encoded_length & 0x3F);
break;
case 1: /* 2-byte encoding (next byte + bits 0-3) */
length = ((ACPI_GET8 (parser_state->aml) << 04) |
(encoded_length & 0x0F));
parser_state->aml++;
break;
case 2: /* 3-byte encoding (next 2 bytes + bits 0-3) */
length = ((ACPI_GET8 (parser_state->aml + 1) << 12) |
(ACPI_GET8 (parser_state->aml) << 04) |
(encoded_length & 0x0F));
parser_state->aml += 2;
break;
case 3: /* 4-byte encoding (next 3 bytes + bits 0-3) */
length = ((ACPI_GET8 (parser_state->aml + 2) << 20) |
(ACPI_GET8 (parser_state->aml + 1) << 12) |
(ACPI_GET8 (parser_state->aml) << 04) |
(encoded_length & 0x0F));
parser_state->aml += 3;
break;
default:
/* Can't get here, only 2 bits / 4 cases */
break;
}
return_VALUE (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;
acpi_native_uint length;
ACPI_FUNCTION_TRACE ("ps_get_next_package_end");
/* Function below changes parser_state->Aml */
length = (acpi_native_uint) acpi_ps_get_next_package_length (parser_state);
return_PTR (start + 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");
/* Handle multiple prefix characters */
while (acpi_ps_is_prefix_char (ACPI_GET8 (end))) {
/* Include prefix '\\' or '^' */
end++;
}
/* Decode the path */
switch (ACPI_GET8 (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 */
end += 2 + ((acpi_size) ACPI_GET8 (end + 1) * ACPI_NAME_SIZE);
break;
default:
/* Single name segment */
end += ACPI_NAME_SIZE;
break;
}
parser_state->aml = (u8*) 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.
* 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 method_call)
{
char *path;
union acpi_parse_object *name_op;
acpi_status status = AE_OK;
union acpi_operand_object *method_desc;
struct acpi_namespace_node *node;
union acpi_generic_state scope_info;
ACPI_FUNCTION_TRACE ("ps_get_next_namepath");
path = acpi_ps_get_next_namestring (parser_state);
/* Null path case is allowed */
if (path) {
/*
* Lookup the name in the internal namespace
*/
scope_info.scope.node = NULL;
node = parser_state->start_node;
if (node) {
scope_info.scope.node = node;
}
/*
* Lookup object. 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 upsearch)
*/
status = acpi_ns_lookup (&scope_info, path, ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE, NULL, &node);
if (ACPI_SUCCESS (status) && method_call) {
if (node->type == ACPI_TYPE_METHOD) {
/*
* 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_REPORT_ERROR ((
"ps_get_next_namepath: Control Method %p has no attached object\n",
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);
}
/*
* Else this is normal named object reference.
* Just init the NAMEPATH object with the pathname.
* (See code below)
*/
}
if (ACPI_FAILURE (status)) {
/*
* 1) Any error other than NOT_FOUND is always severe
* 2) NOT_FOUND is only important if we are executing a method.
* 3) If executing a cond_ref_of opcode, NOT_FOUND is ok.
*/
if ((((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) == ACPI_PARSE_EXECUTE) &&
(status == AE_NOT_FOUND) &&
(walk_state->op->common.aml_opcode != AML_COND_REF_OF_OP)) ||
(status != AE_NOT_FOUND)) {
ACPI_REPORT_NSERROR (path, status);
acpi_os_printf ("search_node %p start_node %p return_node %p\n",
scope_info.scope.node, parser_state->start_node, node);
}
else {
/*
* We got a NOT_FOUND during table load or we encountered
* a cond_ref_of(x) where the target does not exist.
* -- either case is ok
*/
status = AE_OK;
}
}
}
/*
* Regardless of success/failure above,
* Just initialize the Op with the pathname.
*/
acpi_ps_init_op (arg, AML_INT_NAMEPATH_OP);
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)
{
ACPI_FUNCTION_TRACE_U32 ("ps_get_next_simple_arg", arg_type);
switch (arg_type) {
case ARGP_BYTEDATA:
acpi_ps_init_op (arg, AML_BYTE_OP);
arg->common.value.integer = (u32) ACPI_GET8 (parser_state->aml);
parser_state->aml++;
break;
case ARGP_WORDDATA:
acpi_ps_init_op (arg, AML_WORD_OP);
/* Get 2 bytes from the AML stream */
ACPI_MOVE_16_TO_32 (&arg->common.value.integer, parser_state->aml);
parser_state->aml += 2;
break;
case ARGP_DWORDDATA:
acpi_ps_init_op (arg, AML_DWORD_OP);
/* Get 4 bytes from the AML stream */
ACPI_MOVE_32_TO_32 (&arg->common.value.integer, parser_state->aml);
parser_state->aml += 4;
break;
case ARGP_QWORDDATA:
acpi_ps_init_op (arg, AML_QWORD_OP);
/* Get 8 bytes from the AML stream */
ACPI_MOVE_64_TO_64 (&arg->common.value.integer, parser_state->aml);
parser_state->aml += 8;
break;
case ARGP_CHARLIST:
acpi_ps_init_op (arg, AML_STRING_OP);
arg->common.value.string = (char *) parser_state->aml;
while (ACPI_GET8 (parser_state->aml) != '\0') {
parser_state->aml++;
}
parser_state->aml++;
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);
break;
default:
ACPI_REPORT_ERROR (("Invalid arg_type %X\n", arg_type));
break;
}
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)
*
******************************************************************************/
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 = (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: parser_state - Current parser state object
* arg_type - The argument type (AML_*_ARG)
* arg_count - If the argument points to a control method
* the method's argument is returned here.
*
* 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);
}
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_REPORT_ERROR (("Invalid arg_type: %X\n", arg_type));
status = AE_AML_OPERAND_TYPE;
break;
}
*return_arg = arg;
return_ACPI_STATUS (status);
}