Gitiles
Code Review Sign In
gerrit-public.fairphone.software / kernel / msm-4.9 / 5ebd2eaaefc0d4fe37ab72e716e1b8065ed4206c / . / drivers / acpi / acpica / exoparg1.c
blob: 6ae19cb26eb2eb0be6343ef435d0cc2151482010 [file] [log] [blame]
/******************************************************************************
*
* Module Name: exoparg1 - AML execution - opcodes with 1 argument
*
*****************************************************************************/
/*
* Copyright (C) 2000 - 2016, 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 "acdispat.h"
#include "acinterp.h"
#include "amlcode.h"
#include "acnamesp.h"
#define _COMPONENT ACPI_EXECUTER
ACPI_MODULE_NAME("exoparg1")
/*!
* Naming convention for AML interpreter execution routines.
*
* The routines that begin execution of AML opcodes are named with a common
* convention based upon the number of arguments, the number of target operands,
* and whether or not a value is returned:
*
* AcpiExOpcode_xA_yT_zR
*
* Where:
*
* xA - ARGUMENTS: The number of arguments (input operands) that are
* required for this opcode type (0 through 6 args).
* yT - TARGETS: The number of targets (output operands) that are required
* for this opcode type (0, 1, or 2 targets).
* zR - RETURN VALUE: Indicates whether this opcode type returns a value
* as the function return (0 or 1).
*
* The AcpiExOpcode* functions are called via the Dispatcher component with
* fully resolved operands.
!*/
/*******************************************************************************
*
* FUNCTION: acpi_ex_opcode_0A_0T_1R
*
* PARAMETERS: walk_state - Current state (contains AML opcode)
*
* RETURN: Status
*
* DESCRIPTION: Execute operator with no operands, one return value
*
******************************************************************************/
acpi_status acpi_ex_opcode_0A_0T_1R(struct acpi_walk_state *walk_state)
{
acpi_status status = AE_OK;
union acpi_operand_object *return_desc = NULL;
ACPI_FUNCTION_TRACE_STR(ex_opcode_0A_0T_1R,
acpi_ps_get_opcode_name(walk_state->opcode));
/* Examine the AML opcode */
switch (walk_state->opcode) {
case AML_TIMER_OP: /* Timer () */
/* Create a return object of type Integer */
return_desc =
acpi_ut_create_integer_object(acpi_os_get_timer());
if (!return_desc) {
status = AE_NO_MEMORY;
goto cleanup;
}
break;
default: /* Unknown opcode */
ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X",
walk_state->opcode));
status = AE_AML_BAD_OPCODE;
break;
}
cleanup:
/* Delete return object on error */
if ((ACPI_FAILURE(status)) || walk_state->result_obj) {
acpi_ut_remove_reference(return_desc);
walk_state->result_obj = NULL;
} else {
/* Save the return value */
walk_state->result_obj = return_desc;
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_opcode_1A_0T_0R
*
* PARAMETERS: walk_state - Current state (contains AML opcode)
*
* RETURN: Status
*
* DESCRIPTION: Execute Type 1 monadic operator with numeric operand on
* object stack
*
******************************************************************************/
acpi_status acpi_ex_opcode_1A_0T_0R(struct acpi_walk_state *walk_state)
{
union acpi_operand_object **operand = &walk_state->operands[0];
acpi_status status = AE_OK;
ACPI_FUNCTION_TRACE_STR(ex_opcode_1A_0T_0R,
acpi_ps_get_opcode_name(walk_state->opcode));
/* Examine the AML opcode */
switch (walk_state->opcode) {
case AML_RELEASE_OP: /* Release (mutex_object) */
status = acpi_ex_release_mutex(operand[0], walk_state);
break;
case AML_RESET_OP: /* Reset (event_object) */
status = acpi_ex_system_reset_event(operand[0]);
break;
case AML_SIGNAL_OP: /* Signal (event_object) */
status = acpi_ex_system_signal_event(operand[0]);
break;
case AML_SLEEP_OP: /* Sleep (msec_time) */
status = acpi_ex_system_do_sleep(operand[0]->integer.value);
break;
case AML_STALL_OP: /* Stall (usec_time) */
status =
acpi_ex_system_do_stall((u32) operand[0]->integer.value);
break;
case AML_UNLOAD_OP: /* Unload (Handle) */
status = acpi_ex_unload_table(operand[0]);
break;
default: /* Unknown opcode */
ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X",
walk_state->opcode));
status = AE_AML_BAD_OPCODE;
break;
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_opcode_1A_1T_0R
*
* PARAMETERS: walk_state - Current state (contains AML opcode)
*
* RETURN: Status
*
* DESCRIPTION: Execute opcode with one argument, one target, and no
* return value.
*
******************************************************************************/
acpi_status acpi_ex_opcode_1A_1T_0R(struct acpi_walk_state *walk_state)
{
acpi_status status = AE_OK;
union acpi_operand_object **operand = &walk_state->operands[0];
ACPI_FUNCTION_TRACE_STR(ex_opcode_1A_1T_0R,
acpi_ps_get_opcode_name(walk_state->opcode));
/* Examine the AML opcode */
switch (walk_state->opcode) {
case AML_LOAD_OP:
status = acpi_ex_load_op(operand[0], operand[1], walk_state);
break;
default: /* Unknown opcode */
ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X",
walk_state->opcode));
status = AE_AML_BAD_OPCODE;
goto cleanup;
}
cleanup:
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_opcode_1A_1T_1R
*
* PARAMETERS: walk_state - Current state (contains AML opcode)
*
* RETURN: Status
*
* DESCRIPTION: Execute opcode with one argument, one target, and a
* return value.
*
******************************************************************************/
acpi_status acpi_ex_opcode_1A_1T_1R(struct acpi_walk_state *walk_state)
{
acpi_status status = AE_OK;
union acpi_operand_object **operand = &walk_state->operands[0];
union acpi_operand_object *return_desc = NULL;
union acpi_operand_object *return_desc2 = NULL;
u32 temp32;
u32 i;
u64 power_of_ten;
u64 digit;
ACPI_FUNCTION_TRACE_STR(ex_opcode_1A_1T_1R,
acpi_ps_get_opcode_name(walk_state->opcode));
/* Examine the AML opcode */
switch (walk_state->opcode) {
case AML_BIT_NOT_OP:
case AML_FIND_SET_LEFT_BIT_OP:
case AML_FIND_SET_RIGHT_BIT_OP:
case AML_FROM_BCD_OP:
case AML_TO_BCD_OP:
case AML_COND_REF_OF_OP:
/* Create a return object of type Integer for these opcodes */
return_desc = acpi_ut_create_internal_object(ACPI_TYPE_INTEGER);
if (!return_desc) {
status = AE_NO_MEMORY;
goto cleanup;
}
switch (walk_state->opcode) {
case AML_BIT_NOT_OP: /* Not (Operand, Result) */
return_desc->integer.value = ~operand[0]->integer.value;
break;
case AML_FIND_SET_LEFT_BIT_OP: /* find_set_left_bit (Operand, Result) */
return_desc->integer.value = operand[0]->integer.value;
/*
* Acpi specification describes Integer type as a little
* endian unsigned value, so this boundary condition is valid.
*/
for (temp32 = 0; return_desc->integer.value &&
temp32 < ACPI_INTEGER_BIT_SIZE; ++temp32) {
return_desc->integer.value >>= 1;
}
return_desc->integer.value = temp32;
break;
case AML_FIND_SET_RIGHT_BIT_OP: /* find_set_right_bit (Operand, Result) */
return_desc->integer.value = operand[0]->integer.value;
/*
* The Acpi specification describes Integer type as a little
* endian unsigned value, so this boundary condition is valid.
*/
for (temp32 = 0; return_desc->integer.value &&
temp32 < ACPI_INTEGER_BIT_SIZE; ++temp32) {
return_desc->integer.value <<= 1;
}
/* Since the bit position is one-based, subtract from 33 (65) */
return_desc->integer.value =
temp32 ==
0 ? 0 : (ACPI_INTEGER_BIT_SIZE + 1) - temp32;
break;
case AML_FROM_BCD_OP: /* from_bcd (BCDValue, Result) */
/*
* The 64-bit ACPI integer can hold 16 4-bit BCD characters
* (if table is 32-bit, integer can hold 8 BCD characters)
* Convert each 4-bit BCD value
*/
power_of_ten = 1;
return_desc->integer.value = 0;
digit = operand[0]->integer.value;
/* Convert each BCD digit (each is one nybble wide) */
for (i = 0;
(i < acpi_gbl_integer_nybble_width) && (digit > 0);
i++) {
/* Get the least significant 4-bit BCD digit */
temp32 = ((u32) digit) & 0xF;
/* Check the range of the digit */
if (temp32 > 9) {
ACPI_ERROR((AE_INFO,
"BCD digit too large (not decimal): 0x%X",
temp32));
status = AE_AML_NUMERIC_OVERFLOW;
goto cleanup;
}
/* Sum the digit into the result with the current power of 10 */
return_desc->integer.value +=
(((u64) temp32) * power_of_ten);
/* Shift to next BCD digit */
digit >>= 4;
/* Next power of 10 */
power_of_ten *= 10;
}
break;
case AML_TO_BCD_OP: /* to_bcd (Operand, Result) */
return_desc->integer.value = 0;
digit = operand[0]->integer.value;
/* Each BCD digit is one nybble wide */
for (i = 0;
(i < acpi_gbl_integer_nybble_width) && (digit > 0);
i++) {
(void)acpi_ut_short_divide(digit, 10, &digit,
&temp32);
/*
* Insert the BCD digit that resides in the
* remainder from above
*/
return_desc->integer.value |=
(((u64) temp32) << ACPI_MUL_4(i));
}
/* Overflow if there is any data left in Digit */
if (digit > 0) {
ACPI_ERROR((AE_INFO,
"Integer too large to convert to BCD: 0x%8.8X%8.8X",
ACPI_FORMAT_UINT64(operand[0]->
integer.value)));
status = AE_AML_NUMERIC_OVERFLOW;
goto cleanup;
}
break;
case AML_COND_REF_OF_OP: /* cond_ref_of (source_object, Result) */
/*
* This op is a little strange because the internal return value is
* different than the return value stored in the result descriptor
* (There are really two return values)
*/
if ((struct acpi_namespace_node *)operand[0] ==
acpi_gbl_root_node) {
/*
* This means that the object does not exist in the namespace,
* return FALSE
*/
return_desc->integer.value = 0;
goto cleanup;
}
/* Get the object reference, store it, and remove our reference */
status = acpi_ex_get_object_reference(operand[0],
&return_desc2,
walk_state);
if (ACPI_FAILURE(status)) {
goto cleanup;
}
status =
acpi_ex_store(return_desc2, operand[1], walk_state);
acpi_ut_remove_reference(return_desc2);
/* The object exists in the namespace, return TRUE */
return_desc->integer.value = ACPI_UINT64_MAX;
goto cleanup;
default:
/* No other opcodes get here */
break;
}
break;
case AML_STORE_OP: /* Store (Source, Target) */
/*
* A store operand is typically a number, string, buffer or lvalue
* Be careful about deleting the source object,
* since the object itself may have been stored.
*/
status = acpi_ex_store(operand[0], operand[1], walk_state);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* It is possible that the Store already produced a return object */
if (!walk_state->result_obj) {
/*
* Normally, we would remove a reference on the Operand[0]
* parameter; But since it is being used as the internal return
* object (meaning we would normally increment it), the two
* cancel out, and we simply don't do anything.
*/
walk_state->result_obj = operand[0];
walk_state->operands[0] = NULL; /* Prevent deletion */
}
return_ACPI_STATUS(status);
/*
* ACPI 2.0 Opcodes
*/
case AML_COPY_OP: /* Copy (Source, Target) */
status =
acpi_ut_copy_iobject_to_iobject(operand[0], &return_desc,
walk_state);
break;
case AML_TO_DECSTRING_OP: /* to_decimal_string (Data, Result) */
status =
acpi_ex_convert_to_string(operand[0], &return_desc,
ACPI_EXPLICIT_CONVERT_DECIMAL);
if (return_desc == operand[0]) {
/* No conversion performed, add ref to handle return value */
acpi_ut_add_reference(return_desc);
}
break;
case AML_TO_HEXSTRING_OP: /* to_hex_string (Data, Result) */
status =
acpi_ex_convert_to_string(operand[0], &return_desc,
ACPI_EXPLICIT_CONVERT_HEX);
if (return_desc == operand[0]) {
/* No conversion performed, add ref to handle return value */
acpi_ut_add_reference(return_desc);
}
break;
case AML_TO_BUFFER_OP: /* to_buffer (Data, Result) */
status = acpi_ex_convert_to_buffer(operand[0], &return_desc);
if (return_desc == operand[0]) {
/* No conversion performed, add ref to handle return value */
acpi_ut_add_reference(return_desc);
}
break;
case AML_TO_INTEGER_OP: /* to_integer (Data, Result) */
/* Perform "explicit" conversion */
status =
acpi_ex_convert_to_integer(operand[0], &return_desc, 0);
if (return_desc == operand[0]) {
/* No conversion performed, add ref to handle return value */
acpi_ut_add_reference(return_desc);
}
break;
case AML_SHIFT_LEFT_BIT_OP: /* shift_left_bit (Source, bit_num) */
case AML_SHIFT_RIGHT_BIT_OP: /* shift_right_bit (Source, bit_num) */
/* These are two obsolete opcodes */
ACPI_ERROR((AE_INFO,
"%s is obsolete and not implemented",
acpi_ps_get_opcode_name(walk_state->opcode)));
status = AE_SUPPORT;
goto cleanup;
default: /* Unknown opcode */
ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X",
walk_state->opcode));
status = AE_AML_BAD_OPCODE;
goto cleanup;
}
if (ACPI_SUCCESS(status)) {
/* Store the return value computed above into the target object */
status = acpi_ex_store(return_desc, operand[1], walk_state);
}
cleanup:
/* Delete return object on error */
if (ACPI_FAILURE(status)) {
acpi_ut_remove_reference(return_desc);
}
/* Save return object on success */
else if (!walk_state->result_obj) {
walk_state->result_obj = return_desc;
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_opcode_1A_0T_1R
*
* PARAMETERS: walk_state - Current state (contains AML opcode)
*
* RETURN: Status
*
* DESCRIPTION: Execute opcode with one argument, no target, and a return value
*
******************************************************************************/
acpi_status acpi_ex_opcode_1A_0T_1R(struct acpi_walk_state *walk_state)
{
union acpi_operand_object **operand = &walk_state->operands[0];
union acpi_operand_object *temp_desc;
union acpi_operand_object *return_desc = NULL;
acpi_status status = AE_OK;
u32 type;
u64 value;
ACPI_FUNCTION_TRACE_STR(ex_opcode_1A_0T_1R,
acpi_ps_get_opcode_name(walk_state->opcode));
/* Examine the AML opcode */
switch (walk_state->opcode) {
case AML_LNOT_OP: /* LNot (Operand) */
return_desc = acpi_ut_create_integer_object((u64) 0);
if (!return_desc) {
status = AE_NO_MEMORY;
goto cleanup;
}
/*
* Set result to ONES (TRUE) if Value == 0. Note:
* return_desc->Integer.Value is initially == 0 (FALSE) from above.
*/
if (!operand[0]->integer.value) {
return_desc->integer.value = ACPI_UINT64_MAX;
}
break;
case AML_DECREMENT_OP: /* Decrement (Operand) */
case AML_INCREMENT_OP: /* Increment (Operand) */
/*
* Create a new integer. Can't just get the base integer and
* increment it because it may be an Arg or Field.
*/
return_desc = acpi_ut_create_internal_object(ACPI_TYPE_INTEGER);
if (!return_desc) {
status = AE_NO_MEMORY;
goto cleanup;
}
/*
* Since we are expecting a Reference operand, it can be either a
* NS Node or an internal object.
*/
temp_desc = operand[0];
if (ACPI_GET_DESCRIPTOR_TYPE(temp_desc) ==
ACPI_DESC_TYPE_OPERAND) {
/* Internal reference object - prevent deletion */
acpi_ut_add_reference(temp_desc);
}
/*
* Convert the Reference operand to an Integer (This removes a
* reference on the Operand[0] object)
*
* NOTE: We use LNOT_OP here in order to force resolution of the
* reference operand to an actual integer.
*/
status =
acpi_ex_resolve_operands(AML_LNOT_OP, &temp_desc,
walk_state);
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"While resolving operands for [%s]",
acpi_ps_get_opcode_name(walk_state->
opcode)));
goto cleanup;
}
/*
* temp_desc is now guaranteed to be an Integer object --
* Perform the actual increment or decrement
*/
if (walk_state->opcode == AML_INCREMENT_OP) {
return_desc->integer.value =
temp_desc->integer.value + 1;
} else {
return_desc->integer.value =
temp_desc->integer.value - 1;
}
/* Finished with this Integer object */
acpi_ut_remove_reference(temp_desc);
/*
* Store the result back (indirectly) through the original
* Reference object
*/
status = acpi_ex_store(return_desc, operand[0], walk_state);
break;
case AML_OBJECT_TYPE_OP: /* object_type (source_object) */
/*
* Note: The operand is not resolved at this point because we want to
* get the associated object, not its value. For example, we don't
* want to resolve a field_unit to its value, we want the actual
* field_unit object.
*/
/* Get the type of the base object */
status =
acpi_ex_resolve_multiple(walk_state, operand[0], &type,
NULL);
if (ACPI_FAILURE(status)) {
goto cleanup;
}
/* Allocate a descriptor to hold the type. */
return_desc = acpi_ut_create_integer_object((u64) type);
if (!return_desc) {
status = AE_NO_MEMORY;
goto cleanup;
}
break;
case AML_SIZE_OF_OP: /* size_of (source_object) */
/*
* Note: The operand is not resolved at this point because we want to
* get the associated object, not its value.
*/
/* Get the base object */
status =
acpi_ex_resolve_multiple(walk_state, operand[0], &type,
&temp_desc);
if (ACPI_FAILURE(status)) {
goto cleanup;
}
/*
* The type of the base object must be integer, buffer, string, or
* package. All others are not supported.
*
* NOTE: Integer is not specifically supported by the ACPI spec,
* but is supported implicitly via implicit operand conversion.
* rather than bother with conversion, we just use the byte width
* global (4 or 8 bytes).
*/
switch (type) {
case ACPI_TYPE_INTEGER:
value = acpi_gbl_integer_byte_width;
break;
case ACPI_TYPE_STRING:
value = temp_desc->string.length;
break;
case ACPI_TYPE_BUFFER:
/* Buffer arguments may not be evaluated at this point */
status = acpi_ds_get_buffer_arguments(temp_desc);
value = temp_desc->buffer.length;
break;
case ACPI_TYPE_PACKAGE:
/* Package arguments may not be evaluated at this point */
status = acpi_ds_get_package_arguments(temp_desc);
value = temp_desc->package.count;
break;
default:
ACPI_ERROR((AE_INFO,
"Operand must be Buffer/Integer/String/Package"
" - found type %s",
acpi_ut_get_type_name(type)));
status = AE_AML_OPERAND_TYPE;
goto cleanup;
}
if (ACPI_FAILURE(status)) {
goto cleanup;
}
/*
* Now that we have the size of the object, create a result
* object to hold the value
*/
return_desc = acpi_ut_create_integer_object(value);
if (!return_desc) {
status = AE_NO_MEMORY;
goto cleanup;
}
break;
case AML_REF_OF_OP: /* ref_of (source_object) */
status =
acpi_ex_get_object_reference(operand[0], &return_desc,
walk_state);
if (ACPI_FAILURE(status)) {
goto cleanup;
}
break;
case AML_DEREF_OF_OP: /* deref_of (obj_reference | String) */
/* Check for a method local or argument, or standalone String */
if (ACPI_GET_DESCRIPTOR_TYPE(operand[0]) ==
ACPI_DESC_TYPE_NAMED) {
temp_desc =
acpi_ns_get_attached_object((struct
acpi_namespace_node *)
operand[0]);
if (temp_desc
&& ((temp_desc->common.type == ACPI_TYPE_STRING)
|| (temp_desc->common.type ==
ACPI_TYPE_LOCAL_REFERENCE))) {
operand[0] = temp_desc;
acpi_ut_add_reference(temp_desc);
} else {
status = AE_AML_OPERAND_TYPE;
goto cleanup;
}
} else {
switch ((operand[0])->common.type) {
case ACPI_TYPE_LOCAL_REFERENCE:
/*
* This is a deref_of (local_x | arg_x)
*
* Must resolve/dereference the local/arg reference first
*/
switch (operand[0]->reference.class) {
case ACPI_REFCLASS_LOCAL:
case ACPI_REFCLASS_ARG:
/* Set Operand[0] to the value of the local/arg */
status =
acpi_ds_method_data_get_value
(operand[0]->reference.class,
operand[0]->reference.value,
walk_state, &temp_desc);
if (ACPI_FAILURE(status)) {
goto cleanup;
}
/*
* Delete our reference to the input object and
* point to the object just retrieved
*/
acpi_ut_remove_reference(operand[0]);
operand[0] = temp_desc;
break;
case ACPI_REFCLASS_REFOF:
/* Get the object to which the reference refers */
temp_desc =
operand[0]->reference.object;
acpi_ut_remove_reference(operand[0]);
operand[0] = temp_desc;
break;
default:
/* Must be an Index op - handled below */
break;
}
break;
case ACPI_TYPE_STRING:
break;
default:
status = AE_AML_OPERAND_TYPE;
goto cleanup;
}
}
if (ACPI_GET_DESCRIPTOR_TYPE(operand[0]) !=
ACPI_DESC_TYPE_NAMED) {
if ((operand[0])->common.type == ACPI_TYPE_STRING) {
/*
* This is a deref_of (String). The string is a reference
* to a named ACPI object.
*
* 1) Find the owning Node
* 2) Dereference the node to an actual object. Could be a
* Field, so we need to resolve the node to a value.
*/
status =
acpi_ns_get_node(walk_state->scope_info->
scope.node,
operand[0]->string.pointer,
ACPI_NS_SEARCH_PARENT,
ACPI_CAST_INDIRECT_PTR
(struct
acpi_namespace_node,
&return_desc));
if (ACPI_FAILURE(status)) {
goto cleanup;
}
status =
acpi_ex_resolve_node_to_value
(ACPI_CAST_INDIRECT_PTR
(struct acpi_namespace_node, &return_desc),
walk_state);
goto cleanup;
}
}
/* Operand[0] may have changed from the code above */
if (ACPI_GET_DESCRIPTOR_TYPE(operand[0]) ==
ACPI_DESC_TYPE_NAMED) {
/*
* This is a deref_of (object_reference)
* Get the actual object from the Node (This is the dereference).
* This case may only happen when a local_x or arg_x is
* dereferenced above.
*/
return_desc = acpi_ns_get_attached_object((struct
acpi_namespace_node
*)
operand[0]);
acpi_ut_add_reference(return_desc);
} else {
/*
* This must be a reference object produced by either the
* Index() or ref_of() operator
*/
switch (operand[0]->reference.class) {
case ACPI_REFCLASS_INDEX:
/*
* The target type for the Index operator must be
* either a Buffer or a Package
*/
switch (operand[0]->reference.target_type) {
case ACPI_TYPE_BUFFER_FIELD:
temp_desc =
operand[0]->reference.object;
/*
* Create a new object that contains one element of the
* buffer -- the element pointed to by the index.
*
* NOTE: index into a buffer is NOT a pointer to a
* sub-buffer of the main buffer, it is only a pointer to a
* single element (byte) of the buffer!
*
* Since we are returning the value of the buffer at the
* indexed location, we don't need to add an additional
* reference to the buffer itself.
*/
return_desc =
acpi_ut_create_integer_object((u64)
temp_desc->buffer.pointer[operand[0]->reference.value]);
if (!return_desc) {
status = AE_NO_MEMORY;
goto cleanup;
}
break;
case ACPI_TYPE_PACKAGE:
/*
* Return the referenced element of the package. We must
* add another reference to the referenced object, however.
*/
return_desc =
*(operand[0]->reference.where);
if (!return_desc) {
/*
* Element is NULL, do not allow the dereference.
* This provides compatibility with other ACPI
* implementations.
*/
return_ACPI_STATUS
(AE_AML_UNINITIALIZED_ELEMENT);
}
acpi_ut_add_reference(return_desc);
break;
default:
ACPI_ERROR((AE_INFO,
"Unknown Index TargetType 0x%X in reference object %p",
operand[0]->reference.
target_type, operand[0]));
status = AE_AML_OPERAND_TYPE;
goto cleanup;
}
break;
case ACPI_REFCLASS_REFOF:
return_desc = operand[0]->reference.object;
if (ACPI_GET_DESCRIPTOR_TYPE(return_desc) ==
ACPI_DESC_TYPE_NAMED) {
return_desc =
acpi_ns_get_attached_object((struct
acpi_namespace_node
*)
return_desc);
if (!return_desc) {
break;
}
/*
* June 2013:
* buffer_fields/field_units require additional resolution
*/
switch (return_desc->common.type) {
case ACPI_TYPE_BUFFER_FIELD:
case ACPI_TYPE_LOCAL_REGION_FIELD:
case ACPI_TYPE_LOCAL_BANK_FIELD:
case ACPI_TYPE_LOCAL_INDEX_FIELD:
status =
acpi_ex_read_data_from_field
(walk_state, return_desc,
&temp_desc);
if (ACPI_FAILURE(status)) {
goto cleanup;
}
return_desc = temp_desc;
break;
default:
/* Add another reference to the object */
acpi_ut_add_reference
(return_desc);
break;
}
}
break;
default:
ACPI_ERROR((AE_INFO,
"Unknown class in reference(%p) - 0x%2.2X",
operand[0],
operand[0]->reference.class));
status = AE_TYPE;
goto cleanup;
}
}
break;
default:
ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X",
walk_state->opcode));
status = AE_AML_BAD_OPCODE;
goto cleanup;
}
cleanup:
/* Delete return object on error */
if (ACPI_FAILURE(status)) {
acpi_ut_remove_reference(return_desc);
}
/* Save return object on success */
else {
walk_state->result_obj = return_desc;
}
return_ACPI_STATUS(status);
}