Quelle  exresnte.c   Sprache: C

// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
 *
 * Module Name: exresnte - AML Interpreter object resolution
 *
 * Copyright (C) 2000 - 2025, Intel Corp.
 *
 *****************************************************************************/

#include <acpi/acpi.h>
#include "accommon.h"
#include "acdispat.h"
#include "acinterp.h"
#include "acnamesp.h"

#define _COMPONENT          ACPI_EXECUTER
ACPI_MODULE_NAME("exresnte")

/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_resolve_node_to_value
 *
 * PARAMETERS:  object_ptr      - Pointer to a location that contains
 *                                a pointer to a NS node, and will receive a
 *                                pointer to the resolved object.
 *              walk_state      - Current state. Valid only if executing AML
 *                                code. NULL if simply resolving an object
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Resolve a Namespace node to a valued object
 *
 * Note: for some of the data types, the pointer attached to the Node
 * can be either a pointer to an actual internal object or a pointer into the
 * AML stream itself. These types are currently:
 *
 *      ACPI_TYPE_INTEGER
 *      ACPI_TYPE_STRING
 *      ACPI_TYPE_BUFFER
 *      ACPI_TYPE_MUTEX
 *      ACPI_TYPE_PACKAGE
 *
 ******************************************************************************/
acpi_status
acpi_ex_resolve_node_to_value(struct acpi_namespace_node **object_ptr,
         struct acpi_walk_state *walk_state)
{
 acpi_status status = AE_OK;
 union acpi_operand_object *source_desc;
 union acpi_operand_object *obj_desc = NULL;
 struct acpi_namespace_node *node;
 acpi_object_type entry_type;

 ACPI_FUNCTION_TRACE(ex_resolve_node_to_value);

 /*
 * The stack pointer points to a struct acpi_namespace_node (Node). Get the
 * object that is attached to the Node.
 */
 node = *object_ptr;
 source_desc = acpi_ns_get_attached_object(node);
 entry_type = acpi_ns_get_type((acpi_handle)node);

 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Entry=%p SourceDesc=%p [%s]\n",
     node, source_desc,
     acpi_ut_get_type_name(entry_type)));

 if ((entry_type == ACPI_TYPE_LOCAL_ALIAS) ||
     (entry_type == ACPI_TYPE_LOCAL_METHOD_ALIAS)) {

  /* There is always exactly one level of indirection */

  node = ACPI_CAST_PTR(struct acpi_namespace_node, node->object);
  source_desc = acpi_ns_get_attached_object(node);
  entry_type = acpi_ns_get_type((acpi_handle)node);
  *object_ptr = node;
 }

 /*
 * Several object types require no further processing:
 * 1) Device/Thermal objects don't have a "real" subobject, return Node
 * 2) Method locals and arguments have a pseudo-Node
 * 3) 10/2007: Added method type to assist with Package construction.
 */
 if ((entry_type == ACPI_TYPE_DEVICE) ||
     (entry_type == ACPI_TYPE_THERMAL) ||
     (entry_type == ACPI_TYPE_METHOD) ||
     (node->flags & (ANOBJ_METHOD_ARG | ANOBJ_METHOD_LOCAL))) {
  return_ACPI_STATUS(AE_OK);
 }

 if (!source_desc) {
  ACPI_ERROR((AE_INFO, "No object attached to node [%4.4s] %p",
       node->name.ascii, node));
  return_ACPI_STATUS(AE_AML_UNINITIALIZED_NODE);
 }

 /*
 * Action is based on the type of the Node, which indicates the type
 * of the attached object or pointer
 */
 switch (entry_type) {
 case ACPI_TYPE_PACKAGE:

  if (source_desc->common.type != ACPI_TYPE_PACKAGE) {
   ACPI_ERROR((AE_INFO, "Object not a Package, type %s",
        acpi_ut_get_object_type_name(source_desc)));
   return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
  }

  status = acpi_ds_get_package_arguments(source_desc);
  if (ACPI_SUCCESS(status)) {

   /* Return an additional reference to the object */

   obj_desc = source_desc;
   acpi_ut_add_reference(obj_desc);
  }
  break;

 case ACPI_TYPE_BUFFER:

  if (source_desc->common.type != ACPI_TYPE_BUFFER) {
   ACPI_ERROR((AE_INFO, "Object not a Buffer, type %s",
        acpi_ut_get_object_type_name(source_desc)));
   return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
  }

  status = acpi_ds_get_buffer_arguments(source_desc);
  if (ACPI_SUCCESS(status)) {

   /* Return an additional reference to the object */

   obj_desc = source_desc;
   acpi_ut_add_reference(obj_desc);
  }
  break;

 case ACPI_TYPE_STRING:

  if (source_desc->common.type != ACPI_TYPE_STRING) {
   ACPI_ERROR((AE_INFO, "Object not a String, type %s",
        acpi_ut_get_object_type_name(source_desc)));
   return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
  }

  /* Return an additional reference to the object */

  obj_desc = source_desc;
  acpi_ut_add_reference(obj_desc);
  break;

 case ACPI_TYPE_INTEGER:

  if (source_desc->common.type != ACPI_TYPE_INTEGER) {
   ACPI_ERROR((AE_INFO, "Object not a Integer, type %s",
        acpi_ut_get_object_type_name(source_desc)));
   return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
  }

  /* Return an additional reference to the object */

  obj_desc = source_desc;
  acpi_ut_add_reference(obj_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 Node=%p SourceDesc=%p Type=%X\n",
      node, source_desc, entry_type));

  status =
      acpi_ex_read_data_from_field(walk_state, source_desc,
       &obj_desc);
  break;

  /* For these objects, just return the object attached to the Node */

 case ACPI_TYPE_MUTEX:
 case ACPI_TYPE_POWER:
 case ACPI_TYPE_PROCESSOR:
 case ACPI_TYPE_EVENT:
 case ACPI_TYPE_REGION:

  /* Return an additional reference to the object */

  obj_desc = source_desc;
  acpi_ut_add_reference(obj_desc);
  break;

  /* TYPE_ANY is untyped, and thus there is no object associated with it */

 case ACPI_TYPE_ANY:

  ACPI_ERROR((AE_INFO,
       "Untyped entry %p, no attached object!", node));

  return_ACPI_STATUS(AE_AML_OPERAND_TYPE); /* Cannot be AE_TYPE */

 case ACPI_TYPE_LOCAL_REFERENCE:

  switch (source_desc->reference.class) {
  case ACPI_REFCLASS_TABLE: /* This is a ddb_handle */
  case ACPI_REFCLASS_REFOF:
  case ACPI_REFCLASS_INDEX:

   /* Return an additional reference to the object */

   obj_desc = source_desc;
   acpi_ut_add_reference(obj_desc);
   break;

  default:

   /* No named references are allowed here */

   ACPI_ERROR((AE_INFO,
        "Unsupported Reference type 0x%X",
        source_desc->reference.class));

   return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
  }
  break;

 default:

  /* Default case is for unknown types */

  ACPI_ERROR((AE_INFO,
       "Node %p - Unknown object type 0x%X",
       node, entry_type));

  return_ACPI_STATUS(AE_AML_OPERAND_TYPE);

 }   /* switch (entry_type) */

 /* Return the object descriptor */

 *object_ptr = (void *)obj_desc;
 return_ACPI_STATUS(status);
}