// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
*
* Module Name: exresolv - AML Interpreter object resolution
*
* Copyright (C) 2000 - 2025, Intel Corp.
*
*****************************************************************************/
#include <acpi/acpi.h>
#include "accommon.h"
#include "amlcode.h"
#include "acdispat.h"
#include "acinterp.h"
#include "acnamesp.h"
#define _COMPONENT ACPI_EXECUTER
ACPI_MODULE_NAME(
"exresolv")
/* Local prototypes */
static acpi_status
acpi_ex_resolve_object_to_value(
union acpi_operand_object **stack_ptr,
struct acpi_walk_state *walk_state);
/*******************************************************************************
*
* FUNCTION: acpi_ex_resolve_to_value
*
* PARAMETERS: **stack_ptr - Points to entry on obj_stack, which can
* be either an (union acpi_operand_object *)
* or an acpi_handle.
* walk_state - Current method state
*
* RETURN: Status
*
* DESCRIPTION: Convert Reference objects to values
*
******************************************************************************/
acpi_status
acpi_ex_resolve_to_value(
union acpi_operand_object **stack_ptr,
struct acpi_walk_state *walk_state)
{
acpi_status status;
ACPI_FUNCTION_TRACE_PTR(ex_resolve_to_value, stack_ptr);
if (!stack_ptr || !*stack_ptr) {
ACPI_ERROR((AE_INFO,
"Internal - null pointer"));
return_ACPI_STATUS(AE_AML_NO_OPERAND);
}
/*
* The entity pointed to by the stack_ptr can be either
* 1) A valid union acpi_operand_object, or
* 2) A struct acpi_namespace_node (named_obj)
*/
if (ACPI_GET_DESCRIPTOR_TYPE(*stack_ptr) == ACPI_DESC_TYPE_OPERAND) {
status = acpi_ex_resolve_object_to_value(stack_ptr, walk_state);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
if (!*stack_ptr) {
ACPI_ERROR((AE_INFO,
"Internal - null pointer"));
return_ACPI_STATUS(AE_AML_NO_OPERAND);
}
}
/*
* Object on the stack may have changed if acpi_ex_resolve_object_to_value()
* was called (i.e., we can't use an _else_ here.)
*/
if (ACPI_GET_DESCRIPTOR_TYPE(*stack_ptr) == ACPI_DESC_TYPE_NAMED) {
status =
acpi_ex_resolve_node_to_value(ACPI_CAST_INDIRECT_PTR
(
struct acpi_namespace_node,
stack_ptr), walk_state);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
}
ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
"Resolved object %p\n", *stack_ptr));
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_resolve_object_to_value
*
* PARAMETERS: stack_ptr - Pointer to an internal object
* walk_state - Current method state
*
* RETURN: Status
*
* DESCRIPTION: Retrieve the value from an internal object. The Reference type
* uses the associated AML opcode to determine the value.
*
******************************************************************************/
static acpi_status
acpi_ex_resolve_object_to_value(
union acpi_operand_object **stack_ptr,
struct acpi_walk_state *walk_state)
{
acpi_status status = AE_OK;
union acpi_operand_object *stack_desc;
union acpi_operand_object *obj_desc = NULL;
u8 ref_type;
ACPI_FUNCTION_TRACE(ex_resolve_object_to_value);
stack_desc = *stack_ptr;
/* This is an object of type union acpi_operand_object */
switch (stack_desc->common.type) {
case ACPI_TYPE_LOCAL_REFERENCE:
ref_type = stack_desc->reference.
class;
switch (ref_type) {
case ACPI_REFCLASS_LOCAL:
case ACPI_REFCLASS_ARG:
/*
* Get the local from the method's state info
* Note: this increments the local's object reference count
*/
status = acpi_ds_method_data_get_value(ref_type,
stack_desc->
reference.value,
walk_state,
&obj_desc);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
"[Arg/Local %X] ValueObj is %p\n",
stack_desc->reference.value,
obj_desc));
/*
* Now we can delete the original Reference Object and
* replace it with the resolved value
*/
acpi_ut_remove_reference(stack_desc);
*stack_ptr = obj_desc;
break;
case ACPI_REFCLASS_INDEX:
switch (stack_desc->reference.target_type) {
case ACPI_TYPE_BUFFER_FIELD:
/* Just return - do not dereference */
break;
case ACPI_TYPE_PACKAGE:
/* If method call or copy_object - do not dereference */
if ((walk_state->opcode ==
AML_INT_METHODCALL_OP)
|| (walk_state->opcode ==
AML_COPY_OBJECT_OP)) {
break;
}
/* Otherwise, dereference the package_index to a package element */
obj_desc = *stack_desc->reference.where;
if (obj_desc) {
/*
* Valid object descriptor, copy pointer to return value
* (i.e., dereference the package index)
* Delete the ref object, increment the returned object
*/
acpi_ut_add_reference(obj_desc);
*stack_ptr = obj_desc;
}
else {
/*
* A NULL object descriptor means an uninitialized element of
* the package, can't dereference it
*/
ACPI_ERROR((AE_INFO,
"Attempt to dereference an Index to "
"NULL package element Idx=%p",
stack_desc));
status = AE_AML_UNINITIALIZED_ELEMENT;
}
break;
default:
/* Invalid reference object */
ACPI_ERROR((AE_INFO,
"Unknown TargetType 0x%X in Index/Reference object %p",
stack_desc->reference.target_type,
stack_desc));
status = AE_AML_INTERNAL;
break;
}
break;
case ACPI_REFCLASS_REFOF:
case ACPI_REFCLASS_DEBUG:
case ACPI_REFCLASS_TABLE:
/* Just leave the object as-is, do not dereference */
break;
case ACPI_REFCLASS_NAME:
/* Reference to a named object */
/* Dereference the name */
if ((stack_desc->reference.node->type ==
ACPI_TYPE_DEVICE)
|| (stack_desc->reference.node->type ==
ACPI_TYPE_THERMAL)) {
/* These node types do not have 'real' subobjects */
*stack_ptr = (
void *)stack_desc->reference.node;
}
else {
/* Get the object pointed to by the namespace node */
*stack_ptr =
(stack_desc->reference.node)->object;
acpi_ut_add_reference(*stack_ptr);
}
acpi_ut_remove_reference(stack_desc);
break;
default:
ACPI_ERROR((AE_INFO,
"Unknown Reference type 0x%X in %p",
ref_type, stack_desc));
status = AE_AML_INTERNAL;
break;
}
break;
case ACPI_TYPE_BUFFER:
status = acpi_ds_get_buffer_arguments(stack_desc);
break;
case ACPI_TYPE_PACKAGE:
status = acpi_ds_get_package_arguments(stack_desc);
break;
case ACPI_TYPE_BUFFER_FIELD:
case ACPI_TYPE_LOCAL_REGION_FIELD:
case ACPI_TYPE_LOCAL_BANK_FIELD:
case ACPI_TYPE_LOCAL_INDEX_FIELD:
ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
"FieldRead SourceDesc=%p Type=%X\n",
stack_desc, stack_desc->common.type));
status =
acpi_ex_read_data_from_field(walk_state, stack_desc,
&obj_desc);
/* Remove a reference to the original operand, then override */
acpi_ut_remove_reference(*stack_ptr);
*stack_ptr = (
void *)obj_desc;
break;
default:
break;
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_resolve_multiple
*
* PARAMETERS: walk_state - Current state (contains AML opcode)
* operand - Starting point for resolution
* return_type - Where the object type is returned
* return_desc - Where the resolved object is returned
*
* RETURN: Status
*
* DESCRIPTION: Return the base object and type. Traverse a reference list if
* necessary to get to the base object.
*
******************************************************************************/
acpi_status
acpi_ex_resolve_multiple(
struct acpi_walk_state *walk_state,
union acpi_operand_object *operand,
acpi_object_type *return_type,
union acpi_operand_object **return_desc)
{
union acpi_operand_object *obj_desc = ACPI_CAST_PTR(
void, operand);
struct acpi_namespace_node *node =
ACPI_CAST_PTR(
struct acpi_namespace_node, operand);
acpi_object_type type;
acpi_status status;
ACPI_FUNCTION_TRACE(acpi_ex_resolve_multiple);
/* Operand can be either a namespace node or an operand descriptor */
switch (ACPI_GET_DESCRIPTOR_TYPE(obj_desc)) {
case ACPI_DESC_TYPE_OPERAND:
type = obj_desc->common.type;
break;
case ACPI_DESC_TYPE_NAMED:
type = ((
struct acpi_namespace_node *)obj_desc)->type;
obj_desc = acpi_ns_get_attached_object(node);
/* If we had an Alias node, use the attached object for type info */
if (type == ACPI_TYPE_LOCAL_ALIAS) {
type = ((
struct acpi_namespace_node *)obj_desc)->type;
obj_desc = acpi_ns_get_attached_object((
struct
acpi_namespace_node
*)obj_desc);
}
switch (type) {
case ACPI_TYPE_DEVICE:
case ACPI_TYPE_THERMAL:
/* These types have no attached subobject */
break;
default:
/* All other types require a subobject */
if (!obj_desc) {
ACPI_ERROR((AE_INFO,
"[%4.4s] Node is unresolved or uninitialized",
acpi_ut_get_node_name(node)));
return_ACPI_STATUS(AE_AML_UNINITIALIZED_NODE);
}
break;
}
break;
default:
return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
}
/* If type is anything other than a reference, we are done */
if (type != ACPI_TYPE_LOCAL_REFERENCE) {
goto exit;
}
/*
* For reference objects created via the ref_of, Index, or Load/load_table
* operators, we need to get to the base object (as per the ACPI
* specification of the object_type and size_of operators). This means
* traversing the list of possibly many nested references.
*/
while (obj_desc->common.type == ACPI_TYPE_LOCAL_REFERENCE) {
switch (obj_desc->reference.
class) {
case ACPI_REFCLASS_REFOF:
case ACPI_REFCLASS_NAME:
/* Dereference the reference pointer */
if (obj_desc->reference.
class == ACPI_REFCLASS_REFOF) {
node = obj_desc->reference.object;
}
else {
/* AML_INT_NAMEPATH_OP */
node = obj_desc->reference.node;
}
/* All "References" point to a NS node */
if (ACPI_GET_DESCRIPTOR_TYPE(node) !=
ACPI_DESC_TYPE_NAMED) {
ACPI_ERROR((AE_INFO,
"Not a namespace node %p [%s]",
node,
acpi_ut_get_descriptor_name(node)));
return_ACPI_STATUS(AE_AML_INTERNAL);
}
/* Get the attached object */
obj_desc = acpi_ns_get_attached_object(node);
if (!obj_desc) {
/* No object, use the NS node type */
type = acpi_ns_get_type(node);
goto exit;
}
/* Check for circular references */
if (obj_desc == operand) {
return_ACPI_STATUS(AE_AML_CIRCULAR_REFERENCE);
}
break;
case ACPI_REFCLASS_INDEX:
/* Get the type of this reference (index into another object) */
type = obj_desc->reference.target_type;
if (type != ACPI_TYPE_PACKAGE) {
goto exit;
}
/*
* The main object is a package, we want to get the type
* of the individual package element that is referenced by
* the index.
*
* This could of course in turn be another reference object.
*/
obj_desc = *(obj_desc->reference.where);
if (!obj_desc) {
/* NULL package elements are allowed */
type = 0;
/* Uninitialized */
goto exit;
}
break;
case ACPI_REFCLASS_TABLE:
type = ACPI_TYPE_DDB_HANDLE;
goto exit;
case ACPI_REFCLASS_LOCAL:
case ACPI_REFCLASS_ARG:
if (return_desc) {
status =
acpi_ds_method_data_get_value(obj_desc->
reference.
class,
obj_desc->
reference.
value,
walk_state,
&obj_desc);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
acpi_ut_remove_reference(obj_desc);
}
else {
status =
acpi_ds_method_data_get_node(obj_desc->
reference.
class,
obj_desc->
reference.
value,
walk_state,
&node);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
obj_desc = acpi_ns_get_attached_object(node);
if (!obj_desc) {
type = ACPI_TYPE_ANY;
goto exit;
}
}
break;
case ACPI_REFCLASS_DEBUG:
/* The Debug Object is of type "DebugObject" */
type = ACPI_TYPE_DEBUG_OBJECT;
goto exit;
default:
ACPI_ERROR((AE_INFO,
"Unknown Reference Class 0x%2.2X",
obj_desc->reference.
class));
return_ACPI_STATUS(AE_AML_INTERNAL);
}
}
/*
* Now we are guaranteed to have an object that has not been created
* via the ref_of or Index operators.
*/
type = obj_desc->common.type;
exit:
/* Convert internal types to external types */
switch (type) {
case ACPI_TYPE_LOCAL_REGION_FIELD:
case ACPI_TYPE_LOCAL_BANK_FIELD:
case ACPI_TYPE_LOCAL_INDEX_FIELD:
type = ACPI_TYPE_FIELD_UNIT;
break;
case ACPI_TYPE_LOCAL_SCOPE:
/* Per ACPI Specification, Scope is untyped */
type = ACPI_TYPE_ANY;
break;
default:
/* No change to Type required */
break;
}
*return_type = type;
if (return_desc) {
*return_desc = obj_desc;
}
return_ACPI_STATUS(AE_OK);
}
