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-rw-r--r--drivers/acpi/acpica/dsutils.c833
1 files changed, 833 insertions, 0 deletions
diff --git a/drivers/acpi/acpica/dsutils.c b/drivers/acpi/acpica/dsutils.c
new file mode 100644
index 000000000..8d1b75400
--- /dev/null
+++ b/drivers/acpi/acpica/dsutils.c
@@ -0,0 +1,833 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
+/*******************************************************************************
+ *
+ * Module Name: dsutils - Dispatcher utilities
+ *
+ ******************************************************************************/
+
+#include <acpi/acpi.h>
+#include "accommon.h"
+#include "acparser.h"
+#include "amlcode.h"
+#include "acdispat.h"
+#include "acinterp.h"
+#include "acnamesp.h"
+#include "acdebug.h"
+
+#define _COMPONENT ACPI_DISPATCHER
+ACPI_MODULE_NAME("dsutils")
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ds_clear_implicit_return
+ *
+ * PARAMETERS: walk_state - Current State
+ *
+ * RETURN: None.
+ *
+ * DESCRIPTION: Clear and remove a reference on an implicit return value. Used
+ * to delete "stale" return values (if enabled, the return value
+ * from every operator is saved at least momentarily, in case the
+ * parent method exits.)
+ *
+ ******************************************************************************/
+void acpi_ds_clear_implicit_return(struct acpi_walk_state *walk_state)
+{
+ ACPI_FUNCTION_NAME(ds_clear_implicit_return);
+
+ /*
+ * Slack must be enabled for this feature
+ */
+ if (!acpi_gbl_enable_interpreter_slack) {
+ return;
+ }
+
+ if (walk_state->implicit_return_obj) {
+ /*
+ * Delete any "stale" implicit return. However, in
+ * complex statements, the implicit return value can be
+ * bubbled up several levels.
+ */
+ ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+ "Removing reference on stale implicit return obj %p\n",
+ walk_state->implicit_return_obj));
+
+ acpi_ut_remove_reference(walk_state->implicit_return_obj);
+ walk_state->implicit_return_obj = NULL;
+ }
+}
+
+#ifndef ACPI_NO_METHOD_EXECUTION
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ds_do_implicit_return
+ *
+ * PARAMETERS: return_desc - The return value
+ * walk_state - Current State
+ * add_reference - True if a reference should be added to the
+ * return object
+ *
+ * RETURN: TRUE if implicit return enabled, FALSE otherwise
+ *
+ * DESCRIPTION: Implements the optional "implicit return". We save the result
+ * of every ASL operator and control method invocation in case the
+ * parent method exit. Before storing a new return value, we
+ * delete the previous return value.
+ *
+ ******************************************************************************/
+
+u8
+acpi_ds_do_implicit_return(union acpi_operand_object *return_desc,
+ struct acpi_walk_state *walk_state, u8 add_reference)
+{
+ ACPI_FUNCTION_NAME(ds_do_implicit_return);
+
+ /*
+ * Slack must be enabled for this feature, and we must
+ * have a valid return object
+ */
+ if ((!acpi_gbl_enable_interpreter_slack) || (!return_desc)) {
+ return (FALSE);
+ }
+
+ ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+ "Result %p will be implicitly returned; Prev=%p\n",
+ return_desc, walk_state->implicit_return_obj));
+
+ /*
+ * Delete any "stale" implicit return value first. However, in
+ * complex statements, the implicit return value can be
+ * bubbled up several levels, so we don't clear the value if it
+ * is the same as the return_desc.
+ */
+ if (walk_state->implicit_return_obj) {
+ if (walk_state->implicit_return_obj == return_desc) {
+ return (TRUE);
+ }
+ acpi_ds_clear_implicit_return(walk_state);
+ }
+
+ /* Save the implicit return value, add a reference if requested */
+
+ walk_state->implicit_return_obj = return_desc;
+ if (add_reference) {
+ acpi_ut_add_reference(return_desc);
+ }
+
+ return (TRUE);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ds_is_result_used
+ *
+ * PARAMETERS: op - Current Op
+ * walk_state - Current State
+ *
+ * RETURN: TRUE if result is used, FALSE otherwise
+ *
+ * DESCRIPTION: Check if a result object will be used by the parent
+ *
+ ******************************************************************************/
+
+u8
+acpi_ds_is_result_used(union acpi_parse_object * op,
+ struct acpi_walk_state * walk_state)
+{
+ const struct acpi_opcode_info *parent_info;
+
+ ACPI_FUNCTION_TRACE_PTR(ds_is_result_used, op);
+
+ /* Must have both an Op and a Result Object */
+
+ if (!op) {
+ ACPI_ERROR((AE_INFO, "Null Op"));
+ return_UINT8(TRUE);
+ }
+
+ /*
+ * We know that this operator is not a
+ * Return() operator (would not come here.) The following code is the
+ * optional support for a so-called "implicit return". Some AML code
+ * assumes that the last value of the method is "implicitly" returned
+ * to the caller. Just save the last result as the return value.
+ * NOTE: this is optional because the ASL language does not actually
+ * support this behavior.
+ */
+ (void)acpi_ds_do_implicit_return(walk_state->result_obj, walk_state,
+ TRUE);
+
+ /*
+ * Now determine if the parent will use the result
+ *
+ * If there is no parent, or the parent is a scope_op, we are executing
+ * at the method level. An executing method typically has no parent,
+ * since each method is parsed separately. A method invoked externally
+ * via execute_control_method has a scope_op as the parent.
+ */
+ if ((!op->common.parent) ||
+ (op->common.parent->common.aml_opcode == AML_SCOPE_OP)) {
+
+ /* No parent, the return value cannot possibly be used */
+
+ ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+ "At Method level, result of [%s] not used\n",
+ acpi_ps_get_opcode_name(op->common.
+ aml_opcode)));
+ return_UINT8(FALSE);
+ }
+
+ /* Get info on the parent. The root_op is AML_SCOPE */
+
+ parent_info =
+ acpi_ps_get_opcode_info(op->common.parent->common.aml_opcode);
+ if (parent_info->class == AML_CLASS_UNKNOWN) {
+ ACPI_ERROR((AE_INFO, "Unknown parent opcode Op=%p", op));
+ return_UINT8(FALSE);
+ }
+
+ /*
+ * Decide what to do with the result based on the parent. If
+ * the parent opcode will not use the result, delete the object.
+ * Otherwise leave it as is, it will be deleted when it is used
+ * as an operand later.
+ */
+ switch (parent_info->class) {
+ case AML_CLASS_CONTROL:
+
+ switch (op->common.parent->common.aml_opcode) {
+ case AML_RETURN_OP:
+
+ /* Never delete the return value associated with a return opcode */
+
+ goto result_used;
+
+ case AML_IF_OP:
+ case AML_WHILE_OP:
+ /*
+ * If we are executing the predicate AND this is the predicate op,
+ * we will use the return value
+ */
+ if ((walk_state->control_state->common.state ==
+ ACPI_CONTROL_PREDICATE_EXECUTING) &&
+ (walk_state->control_state->control.predicate_op ==
+ op)) {
+ goto result_used;
+ }
+ break;
+
+ default:
+
+ /* Ignore other control opcodes */
+
+ break;
+ }
+
+ /* The general control opcode returns no result */
+
+ goto result_not_used;
+
+ case AML_CLASS_CREATE:
+ /*
+ * These opcodes allow term_arg(s) as operands and therefore
+ * the operands can be method calls. The result is used.
+ */
+ goto result_used;
+
+ case AML_CLASS_NAMED_OBJECT:
+
+ if ((op->common.parent->common.aml_opcode == AML_REGION_OP) ||
+ (op->common.parent->common.aml_opcode == AML_DATA_REGION_OP)
+ || (op->common.parent->common.aml_opcode == AML_PACKAGE_OP)
+ || (op->common.parent->common.aml_opcode == AML_BUFFER_OP)
+ || (op->common.parent->common.aml_opcode ==
+ AML_VARIABLE_PACKAGE_OP)
+ || (op->common.parent->common.aml_opcode ==
+ AML_INT_EVAL_SUBTREE_OP)
+ || (op->common.parent->common.aml_opcode ==
+ AML_BANK_FIELD_OP)) {
+ /*
+ * These opcodes allow term_arg(s) as operands and therefore
+ * the operands can be method calls. The result is used.
+ */
+ goto result_used;
+ }
+
+ goto result_not_used;
+
+ default:
+ /*
+ * In all other cases. the parent will actually use the return
+ * object, so keep it.
+ */
+ goto result_used;
+ }
+
+result_used:
+ ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+ "Result of [%s] used by Parent [%s] Op=%p\n",
+ acpi_ps_get_opcode_name(op->common.aml_opcode),
+ acpi_ps_get_opcode_name(op->common.parent->common.
+ aml_opcode), op));
+
+ return_UINT8(TRUE);
+
+result_not_used:
+ ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+ "Result of [%s] not used by Parent [%s] Op=%p\n",
+ acpi_ps_get_opcode_name(op->common.aml_opcode),
+ acpi_ps_get_opcode_name(op->common.parent->common.
+ aml_opcode), op));
+
+ return_UINT8(FALSE);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ds_delete_result_if_not_used
+ *
+ * PARAMETERS: op - Current parse Op
+ * result_obj - Result of the operation
+ * walk_state - Current state
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Used after interpretation of an opcode. If there is an internal
+ * result descriptor, check if the parent opcode will actually use
+ * this result. If not, delete the result now so that it will
+ * not become orphaned.
+ *
+ ******************************************************************************/
+
+void
+acpi_ds_delete_result_if_not_used(union acpi_parse_object *op,
+ union acpi_operand_object *result_obj,
+ struct acpi_walk_state *walk_state)
+{
+ union acpi_operand_object *obj_desc;
+ acpi_status status;
+
+ ACPI_FUNCTION_TRACE_PTR(ds_delete_result_if_not_used, result_obj);
+
+ if (!op) {
+ ACPI_ERROR((AE_INFO, "Null Op"));
+ return_VOID;
+ }
+
+ if (!result_obj) {
+ return_VOID;
+ }
+
+ if (!acpi_ds_is_result_used(op, walk_state)) {
+
+ /* Must pop the result stack (obj_desc should be equal to result_obj) */
+
+ status = acpi_ds_result_pop(&obj_desc, walk_state);
+ if (ACPI_SUCCESS(status)) {
+ acpi_ut_remove_reference(result_obj);
+ }
+ }
+
+ return_VOID;
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ds_resolve_operands
+ *
+ * PARAMETERS: walk_state - Current walk state with operands on stack
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Resolve all operands to their values. Used to prepare
+ * arguments to a control method invocation (a call from one
+ * method to another.)
+ *
+ ******************************************************************************/
+
+acpi_status acpi_ds_resolve_operands(struct acpi_walk_state *walk_state)
+{
+ u32 i;
+ acpi_status status = AE_OK;
+
+ ACPI_FUNCTION_TRACE_PTR(ds_resolve_operands, walk_state);
+
+ /*
+ * Attempt to resolve each of the valid operands
+ * Method arguments are passed by reference, not by value. This means
+ * that the actual objects are passed, not copies of the objects.
+ */
+ for (i = 0; i < walk_state->num_operands; i++) {
+ status =
+ acpi_ex_resolve_to_value(&walk_state->operands[i],
+ walk_state);
+ if (ACPI_FAILURE(status)) {
+ break;
+ }
+ }
+
+ return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ds_clear_operands
+ *
+ * PARAMETERS: walk_state - Current walk state with operands on stack
+ *
+ * RETURN: None
+ *
+ * DESCRIPTION: Clear all operands on the current walk state operand stack.
+ *
+ ******************************************************************************/
+
+void acpi_ds_clear_operands(struct acpi_walk_state *walk_state)
+{
+ u32 i;
+
+ ACPI_FUNCTION_TRACE_PTR(ds_clear_operands, walk_state);
+
+ /* Remove a reference on each operand on the stack */
+
+ for (i = 0; i < walk_state->num_operands; i++) {
+ /*
+ * Remove a reference to all operands, including both
+ * "Arguments" and "Targets".
+ */
+ acpi_ut_remove_reference(walk_state->operands[i]);
+ walk_state->operands[i] = NULL;
+ }
+
+ walk_state->num_operands = 0;
+ return_VOID;
+}
+#endif
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ds_create_operand
+ *
+ * PARAMETERS: walk_state - Current walk state
+ * arg - Parse object for the argument
+ * arg_index - Which argument (zero based)
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Translate a parse tree object that is an argument to an AML
+ * opcode to the equivalent interpreter object. This may include
+ * looking up a name or entering a new name into the internal
+ * namespace.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ds_create_operand(struct acpi_walk_state *walk_state,
+ union acpi_parse_object *arg, u32 arg_index)
+{
+ acpi_status status = AE_OK;
+ char *name_string;
+ u32 name_length;
+ union acpi_operand_object *obj_desc;
+ union acpi_parse_object *parent_op;
+ u16 opcode;
+ acpi_interpreter_mode interpreter_mode;
+ const struct acpi_opcode_info *op_info;
+
+ ACPI_FUNCTION_TRACE_PTR(ds_create_operand, arg);
+
+ /* A valid name must be looked up in the namespace */
+
+ if ((arg->common.aml_opcode == AML_INT_NAMEPATH_OP) &&
+ (arg->common.value.string) &&
+ !(arg->common.flags & ACPI_PARSEOP_IN_STACK)) {
+ ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "Getting a name: Arg=%p\n",
+ arg));
+
+ /* Get the entire name string from the AML stream */
+
+ status = acpi_ex_get_name_string(ACPI_TYPE_ANY,
+ arg->common.value.buffer,
+ &name_string, &name_length);
+
+ if (ACPI_FAILURE(status)) {
+ return_ACPI_STATUS(status);
+ }
+
+ /* All prefixes have been handled, and the name is in name_string */
+
+ /*
+ * Special handling for buffer_field declarations. This is a deferred
+ * opcode that unfortunately defines the field name as the last
+ * parameter instead of the first. We get here when we are performing
+ * the deferred execution, so the actual name of the field is already
+ * in the namespace. We don't want to attempt to look it up again
+ * because we may be executing in a different scope than where the
+ * actual opcode exists.
+ */
+ if ((walk_state->deferred_node) &&
+ (walk_state->deferred_node->type == ACPI_TYPE_BUFFER_FIELD)
+ && (arg_index == (u32)
+ ((walk_state->opcode == AML_CREATE_FIELD_OP) ? 3 : 2))) {
+ obj_desc =
+ ACPI_CAST_PTR(union acpi_operand_object,
+ walk_state->deferred_node);
+ status = AE_OK;
+ } else { /* All other opcodes */
+
+ /*
+ * Differentiate between a namespace "create" operation
+ * versus a "lookup" operation (IMODE_LOAD_PASS2 vs.
+ * IMODE_EXECUTE) in order to support the creation of
+ * namespace objects during the execution of control methods.
+ */
+ parent_op = arg->common.parent;
+ op_info =
+ acpi_ps_get_opcode_info(parent_op->common.
+ aml_opcode);
+
+ if ((op_info->flags & AML_NSNODE) &&
+ (parent_op->common.aml_opcode !=
+ AML_INT_METHODCALL_OP)
+ && (parent_op->common.aml_opcode != AML_REGION_OP)
+ && (parent_op->common.aml_opcode !=
+ AML_INT_NAMEPATH_OP)) {
+
+ /* Enter name into namespace if not found */
+
+ interpreter_mode = ACPI_IMODE_LOAD_PASS2;
+ } else {
+ /* Return a failure if name not found */
+
+ interpreter_mode = ACPI_IMODE_EXECUTE;
+ }
+
+ status =
+ acpi_ns_lookup(walk_state->scope_info, name_string,
+ ACPI_TYPE_ANY, interpreter_mode,
+ ACPI_NS_SEARCH_PARENT |
+ ACPI_NS_DONT_OPEN_SCOPE, walk_state,
+ ACPI_CAST_INDIRECT_PTR(struct
+ acpi_namespace_node,
+ &obj_desc));
+ /*
+ * The only case where we pass through (ignore) a NOT_FOUND
+ * error is for the cond_ref_of opcode.
+ */
+ if (status == AE_NOT_FOUND) {
+ if (parent_op->common.aml_opcode ==
+ AML_CONDITIONAL_REF_OF_OP) {
+ /*
+ * For the Conditional Reference op, it's OK if
+ * the name is not found; We just need a way to
+ * indicate this to the interpreter, set the
+ * object to the root
+ */
+ obj_desc =
+ ACPI_CAST_PTR(union
+ acpi_operand_object,
+ acpi_gbl_root_node);
+ status = AE_OK;
+ } else if (parent_op->common.aml_opcode ==
+ AML_EXTERNAL_OP) {
+ /*
+ * This opcode should never appear here. It is used only
+ * by AML disassemblers and is surrounded by an If(0)
+ * by the ASL compiler.
+ *
+ * Therefore, if we see it here, it is a serious error.
+ */
+ status = AE_AML_BAD_OPCODE;
+ } else {
+ /*
+ * We just plain didn't find it -- which is a
+ * very serious error at this point
+ */
+ status = AE_AML_NAME_NOT_FOUND;
+ }
+ }
+
+ if (ACPI_FAILURE(status)) {
+ ACPI_ERROR_NAMESPACE(walk_state->scope_info,
+ name_string, status);
+ }
+ }
+
+ /* Free the namestring created above */
+
+ ACPI_FREE(name_string);
+
+ /* Check status from the lookup */
+
+ if (ACPI_FAILURE(status)) {
+ return_ACPI_STATUS(status);
+ }
+
+ /* Put the resulting object onto the current object stack */
+
+ status = acpi_ds_obj_stack_push(obj_desc, walk_state);
+ if (ACPI_FAILURE(status)) {
+ return_ACPI_STATUS(status);
+ }
+
+ acpi_db_display_argument_object(obj_desc, walk_state);
+ } else {
+ /* Check for null name case */
+
+ if ((arg->common.aml_opcode == AML_INT_NAMEPATH_OP) &&
+ !(arg->common.flags & ACPI_PARSEOP_IN_STACK)) {
+ /*
+ * If the name is null, this means that this is an
+ * optional result parameter that was not specified
+ * in the original ASL. Create a Zero Constant for a
+ * placeholder. (Store to a constant is a Noop.)
+ */
+ opcode = AML_ZERO_OP; /* Has no arguments! */
+
+ ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+ "Null namepath: Arg=%p\n", arg));
+ } else {
+ opcode = arg->common.aml_opcode;
+ }
+
+ /* Get the object type of the argument */
+
+ op_info = acpi_ps_get_opcode_info(opcode);
+ if (op_info->object_type == ACPI_TYPE_INVALID) {
+ return_ACPI_STATUS(AE_NOT_IMPLEMENTED);
+ }
+
+ if ((op_info->flags & AML_HAS_RETVAL) ||
+ (arg->common.flags & ACPI_PARSEOP_IN_STACK)) {
+ /*
+ * Use value that was already previously returned
+ * by the evaluation of this argument
+ */
+ status = acpi_ds_result_pop(&obj_desc, walk_state);
+ if (ACPI_FAILURE(status)) {
+ /*
+ * Only error is underflow, and this indicates
+ * a missing or null operand!
+ */
+ ACPI_EXCEPTION((AE_INFO, status,
+ "Missing or null operand"));
+ return_ACPI_STATUS(status);
+ }
+ } else {
+ /* Create an ACPI_INTERNAL_OBJECT for the argument */
+
+ obj_desc =
+ acpi_ut_create_internal_object(op_info->
+ object_type);
+ if (!obj_desc) {
+ return_ACPI_STATUS(AE_NO_MEMORY);
+ }
+
+ /* Initialize the new object */
+
+ status =
+ acpi_ds_init_object_from_op(walk_state, arg, opcode,
+ &obj_desc);
+ if (ACPI_FAILURE(status)) {
+ acpi_ut_delete_object_desc(obj_desc);
+ return_ACPI_STATUS(status);
+ }
+ }
+
+ /* Put the operand object on the object stack */
+
+ status = acpi_ds_obj_stack_push(obj_desc, walk_state);
+ if (ACPI_FAILURE(status)) {
+ return_ACPI_STATUS(status);
+ }
+
+ acpi_db_display_argument_object(obj_desc, walk_state);
+ }
+
+ return_ACPI_STATUS(AE_OK);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ds_create_operands
+ *
+ * PARAMETERS: walk_state - Current state
+ * first_arg - First argument of a parser argument tree
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Convert an operator's arguments from a parse tree format to
+ * namespace objects and place those argument object on the object
+ * stack in preparation for evaluation by the interpreter.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ds_create_operands(struct acpi_walk_state *walk_state,
+ union acpi_parse_object *first_arg)
+{
+ acpi_status status = AE_OK;
+ union acpi_parse_object *arg;
+ union acpi_parse_object *arguments[ACPI_OBJ_NUM_OPERANDS];
+ u32 arg_count = 0;
+ u32 index = walk_state->num_operands;
+ u32 i;
+
+ ACPI_FUNCTION_TRACE_PTR(ds_create_operands, first_arg);
+
+ /* Get all arguments in the list */
+
+ arg = first_arg;
+ while (arg) {
+ if (index >= ACPI_OBJ_NUM_OPERANDS) {
+ return_ACPI_STATUS(AE_BAD_DATA);
+ }
+
+ arguments[index] = arg;
+ walk_state->operands[index] = NULL;
+
+ /* Move on to next argument, if any */
+
+ arg = arg->common.next;
+ arg_count++;
+ index++;
+ }
+
+ ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+ "NumOperands %d, ArgCount %d, Index %d\n",
+ walk_state->num_operands, arg_count, index));
+
+ /* Create the interpreter arguments, in reverse order */
+
+ index--;
+ for (i = 0; i < arg_count; i++) {
+ arg = arguments[index];
+ walk_state->operand_index = (u8)index;
+
+ status = acpi_ds_create_operand(walk_state, arg, index);
+ if (ACPI_FAILURE(status)) {
+ goto cleanup;
+ }
+
+ ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+ "Created Arg #%u (%p) %u args total\n",
+ index, arg, arg_count));
+ index--;
+ }
+
+ return_ACPI_STATUS(status);
+
+cleanup:
+ /*
+ * We must undo everything done above; meaning that we must
+ * pop everything off of the operand stack and delete those
+ * objects
+ */
+ acpi_ds_obj_stack_pop_and_delete(arg_count, walk_state);
+
+ ACPI_EXCEPTION((AE_INFO, status, "While creating Arg %u", index));
+ return_ACPI_STATUS(status);
+}
+
+/*****************************************************************************
+ *
+ * FUNCTION: acpi_ds_evaluate_name_path
+ *
+ * PARAMETERS: walk_state - Current state of the parse tree walk,
+ * the opcode of current operation should be
+ * AML_INT_NAMEPATH_OP
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Translate the -name_path- parse tree object to the equivalent
+ * interpreter object, convert it to value, if needed, duplicate
+ * it, if needed, and push it onto the current result stack.
+ *
+ ****************************************************************************/
+
+acpi_status acpi_ds_evaluate_name_path(struct acpi_walk_state *walk_state)
+{
+ acpi_status status = AE_OK;
+ union acpi_parse_object *op = walk_state->op;
+ union acpi_operand_object **operand = &walk_state->operands[0];
+ union acpi_operand_object *new_obj_desc;
+ u8 type;
+
+ ACPI_FUNCTION_TRACE_PTR(ds_evaluate_name_path, walk_state);
+
+ if (!op->common.parent) {
+
+ /* This happens after certain exception processing */
+
+ goto exit;
+ }
+
+ if ((op->common.parent->common.aml_opcode == AML_PACKAGE_OP) ||
+ (op->common.parent->common.aml_opcode == AML_VARIABLE_PACKAGE_OP) ||
+ (op->common.parent->common.aml_opcode == AML_REF_OF_OP)) {
+
+ /* TBD: Should we specify this feature as a bit of op_info->Flags of these opcodes? */
+
+ goto exit;
+ }
+
+ status = acpi_ds_create_operand(walk_state, op, 0);
+ if (ACPI_FAILURE(status)) {
+ goto exit;
+ }
+
+ if (op->common.flags & ACPI_PARSEOP_TARGET) {
+ new_obj_desc = *operand;
+ goto push_result;
+ }
+
+ type = (*operand)->common.type;
+
+ status = acpi_ex_resolve_to_value(operand, walk_state);
+ if (ACPI_FAILURE(status)) {
+ goto exit;
+ }
+
+ if (type == ACPI_TYPE_INTEGER) {
+
+ /* It was incremented by acpi_ex_resolve_to_value */
+
+ acpi_ut_remove_reference(*operand);
+
+ status =
+ acpi_ut_copy_iobject_to_iobject(*operand, &new_obj_desc,
+ walk_state);
+ if (ACPI_FAILURE(status)) {
+ goto exit;
+ }
+ } else {
+ /*
+ * The object either was anew created or is
+ * a Namespace node - don't decrement it.
+ */
+ new_obj_desc = *operand;
+ }
+
+ /* Cleanup for name-path operand */
+
+ status = acpi_ds_obj_stack_pop(1, walk_state);
+ if (ACPI_FAILURE(status)) {
+ walk_state->result_obj = new_obj_desc;
+ goto exit;
+ }
+
+push_result:
+
+ walk_state->result_obj = new_obj_desc;
+
+ status = acpi_ds_result_push(walk_state->result_obj, walk_state);
+ if (ACPI_SUCCESS(status)) {
+
+ /* Force to take it from stack */
+
+ op->common.flags |= ACPI_PARSEOP_IN_STACK;
+ }
+
+exit:
+
+ return_ACPI_STATUS(status);
+}