1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2/******************************************************************************
3 *
4 * Module Name: exresnte - AML Interpreter object resolution
5 *
6 * Copyright (C) 2000 - 2023, Intel Corp.
7 *
8 *****************************************************************************/
9
10#include <acpi/acpi.h>
11#include "accommon.h"
12#include "acdispat.h"
13#include "acinterp.h"
14#include "acnamesp.h"
15
16#define _COMPONENT          ACPI_EXECUTER
17ACPI_MODULE_NAME("exresnte")
18
19/*******************************************************************************
20 *
21 * FUNCTION:    acpi_ex_resolve_node_to_value
22 *
23 * PARAMETERS:  object_ptr      - Pointer to a location that contains
24 *                                a pointer to a NS node, and will receive a
25 *                                pointer to the resolved object.
26 *              walk_state      - Current state. Valid only if executing AML
27 *                                code. NULL if simply resolving an object
28 *
29 * RETURN:      Status
30 *
31 * DESCRIPTION: Resolve a Namespace node to a valued object
32 *
33 * Note: for some of the data types, the pointer attached to the Node
34 * can be either a pointer to an actual internal object or a pointer into the
35 * AML stream itself. These types are currently:
36 *
37 *      ACPI_TYPE_INTEGER
38 *      ACPI_TYPE_STRING
39 *      ACPI_TYPE_BUFFER
40 *      ACPI_TYPE_MUTEX
41 *      ACPI_TYPE_PACKAGE
42 *
43 ******************************************************************************/
44acpi_status
45acpi_ex_resolve_node_to_value(struct acpi_namespace_node **object_ptr,
46			      struct acpi_walk_state *walk_state)
47{
48	acpi_status status = AE_OK;
49	union acpi_operand_object *source_desc;
50	union acpi_operand_object *obj_desc = NULL;
51	struct acpi_namespace_node *node;
52	acpi_object_type entry_type;
53
54	ACPI_FUNCTION_TRACE(ex_resolve_node_to_value);
55
56	/*
57	 * The stack pointer points to a struct acpi_namespace_node (Node). Get the
58	 * object that is attached to the Node.
59	 */
60	node = *object_ptr;
61	source_desc = acpi_ns_get_attached_object(node);
62	entry_type = acpi_ns_get_type((acpi_handle)node);
63
64	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Entry=%p SourceDesc=%p [%s]\n",
65			  node, source_desc,
66			  acpi_ut_get_type_name(entry_type)));
67
68	if ((entry_type == ACPI_TYPE_LOCAL_ALIAS) ||
69	    (entry_type == ACPI_TYPE_LOCAL_METHOD_ALIAS)) {
70
71		/* There is always exactly one level of indirection */
72
73		node = ACPI_CAST_PTR(struct acpi_namespace_node, node->object);
74		source_desc = acpi_ns_get_attached_object(node);
75		entry_type = acpi_ns_get_type((acpi_handle)node);
76		*object_ptr = node;
77	}
78
79	/*
80	 * Several object types require no further processing:
81	 * 1) Device/Thermal objects don't have a "real" subobject, return Node
82	 * 2) Method locals and arguments have a pseudo-Node
83	 * 3) 10/2007: Added method type to assist with Package construction.
84	 */
85	if ((entry_type == ACPI_TYPE_DEVICE) ||
86	    (entry_type == ACPI_TYPE_THERMAL) ||
87	    (entry_type == ACPI_TYPE_METHOD) ||
88	    (node->flags & (ANOBJ_METHOD_ARG | ANOBJ_METHOD_LOCAL))) {
89		return_ACPI_STATUS(AE_OK);
90	}
91
92	if (!source_desc) {
93		ACPI_ERROR((AE_INFO, "No object attached to node [%4.4s] %p",
94			    node->name.ascii, node));
95		return_ACPI_STATUS(AE_AML_UNINITIALIZED_NODE);
96	}
97
98	/*
99	 * Action is based on the type of the Node, which indicates the type
100	 * of the attached object or pointer
101	 */
102	switch (entry_type) {
103	case ACPI_TYPE_PACKAGE:
104
105		if (source_desc->common.type != ACPI_TYPE_PACKAGE) {
106			ACPI_ERROR((AE_INFO, "Object not a Package, type %s",
107				    acpi_ut_get_object_type_name(source_desc)));
108			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
109		}
110
111		status = acpi_ds_get_package_arguments(source_desc);
112		if (ACPI_SUCCESS(status)) {
113
114			/* Return an additional reference to the object */
115
116			obj_desc = source_desc;
117			acpi_ut_add_reference(obj_desc);
118		}
119		break;
120
121	case ACPI_TYPE_BUFFER:
122
123		if (source_desc->common.type != ACPI_TYPE_BUFFER) {
124			ACPI_ERROR((AE_INFO, "Object not a Buffer, type %s",
125				    acpi_ut_get_object_type_name(source_desc)));
126			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
127		}
128
129		status = acpi_ds_get_buffer_arguments(source_desc);
130		if (ACPI_SUCCESS(status)) {
131
132			/* Return an additional reference to the object */
133
134			obj_desc = source_desc;
135			acpi_ut_add_reference(obj_desc);
136		}
137		break;
138
139	case ACPI_TYPE_STRING:
140
141		if (source_desc->common.type != ACPI_TYPE_STRING) {
142			ACPI_ERROR((AE_INFO, "Object not a String, type %s",
143				    acpi_ut_get_object_type_name(source_desc)));
144			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
145		}
146
147		/* Return an additional reference to the object */
148
149		obj_desc = source_desc;
150		acpi_ut_add_reference(obj_desc);
151		break;
152
153	case ACPI_TYPE_INTEGER:
154
155		if (source_desc->common.type != ACPI_TYPE_INTEGER) {
156			ACPI_ERROR((AE_INFO, "Object not a Integer, type %s",
157				    acpi_ut_get_object_type_name(source_desc)));
158			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
159		}
160
161		/* Return an additional reference to the object */
162
163		obj_desc = source_desc;
164		acpi_ut_add_reference(obj_desc);
165		break;
166
167	case ACPI_TYPE_BUFFER_FIELD:
168	case ACPI_TYPE_LOCAL_REGION_FIELD:
169	case ACPI_TYPE_LOCAL_BANK_FIELD:
170	case ACPI_TYPE_LOCAL_INDEX_FIELD:
171
172		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
173				  "FieldRead Node=%p SourceDesc=%p Type=%X\n",
174				  node, source_desc, entry_type));
175
176		status =
177		    acpi_ex_read_data_from_field(walk_state, source_desc,
178						 &obj_desc);
179		break;
180
181		/* For these objects, just return the object attached to the Node */
182
183	case ACPI_TYPE_MUTEX:
184	case ACPI_TYPE_POWER:
185	case ACPI_TYPE_PROCESSOR:
186	case ACPI_TYPE_EVENT:
187	case ACPI_TYPE_REGION:
188
189		/* Return an additional reference to the object */
190
191		obj_desc = source_desc;
192		acpi_ut_add_reference(obj_desc);
193		break;
194
195		/* TYPE_ANY is untyped, and thus there is no object associated with it */
196
197	case ACPI_TYPE_ANY:
198
199		ACPI_ERROR((AE_INFO,
200			    "Untyped entry %p, no attached object!", node));
201
202		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);	/* Cannot be AE_TYPE */
203
204	case ACPI_TYPE_LOCAL_REFERENCE:
205
206		switch (source_desc->reference.class) {
207		case ACPI_REFCLASS_TABLE:	/* This is a ddb_handle */
208		case ACPI_REFCLASS_REFOF:
209		case ACPI_REFCLASS_INDEX:
210
211			/* Return an additional reference to the object */
212
213			obj_desc = source_desc;
214			acpi_ut_add_reference(obj_desc);
215			break;
216
217		default:
218
219			/* No named references are allowed here */
220
221			ACPI_ERROR((AE_INFO,
222				    "Unsupported Reference type 0x%X",
223				    source_desc->reference.class));
224
225			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
226		}
227		break;
228
229	default:
230
231		/* Default case is for unknown types */
232
233		ACPI_ERROR((AE_INFO,
234			    "Node %p - Unknown object type 0x%X",
235			    node, entry_type));
236
237		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
238
239	}			/* switch (entry_type) */
240
241	/* Return the object descriptor */
242
243	*object_ptr = (void *)obj_desc;
244	return_ACPI_STATUS(status);
245}
246