1
2/******************************************************************************
3 *
4 * Module Name: exresnte - AML Interpreter object resolution
5 *
6 *****************************************************************************/
7
8/*
9 * Copyright (C) 2000 - 2007, R. Byron Moore
10 * All rights reserved.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 *    notice, this list of conditions, and the following disclaimer,
17 *    without modification.
18 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
19 *    substantially similar to the "NO WARRANTY" disclaimer below
20 *    ("Disclaimer") and any redistribution must be conditioned upon
21 *    including a substantially similar Disclaimer requirement for further
22 *    binary redistribution.
23 * 3. Neither the names of the above-listed copyright holders nor the names
24 *    of any contributors may be used to endorse or promote products derived
25 *    from this software without specific prior written permission.
26 *
27 * Alternatively, this software may be distributed under the terms of the
28 * GNU General Public License ("GPL") version 2 as published by the Free
29 * Software Foundation.
30 *
31 * NO WARRANTY
32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
35 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
36 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
41 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42 * POSSIBILITY OF SUCH DAMAGES.
43 */
44
45#include <acpi/acpi.h>
46#include <acpi/acdispat.h>
47#include <acpi/acinterp.h>
48#include <acpi/acnamesp.h>
49#include <acpi/acparser.h>
50#include <acpi/amlcode.h>
51
52#define _COMPONENT          ACPI_EXECUTER
53ACPI_MODULE_NAME("exresnte")
54
55/*******************************************************************************
56 *
57 * FUNCTION:    acpi_ex_resolve_node_to_value
58 *
59 * PARAMETERS:  object_ptr      - Pointer to a location that contains
60 *                                a pointer to a NS node, and will receive a
61 *                                pointer to the resolved object.
62 *              walk_state      - Current state.  Valid only if executing AML
63 *                                code.  NULL if simply resolving an object
64 *
65 * RETURN:      Status
66 *
67 * DESCRIPTION: Resolve a Namespace node to a valued object
68 *
69 * Note: for some of the data types, the pointer attached to the Node
70 * can be either a pointer to an actual internal object or a pointer into the
71 * AML stream itself.  These types are currently:
72 *
73 *      ACPI_TYPE_INTEGER
74 *      ACPI_TYPE_STRING
75 *      ACPI_TYPE_BUFFER
76 *      ACPI_TYPE_MUTEX
77 *      ACPI_TYPE_PACKAGE
78 *
79 ******************************************************************************/
80acpi_status
81acpi_ex_resolve_node_to_value(struct acpi_namespace_node **object_ptr,
82			      struct acpi_walk_state *walk_state)
83{
84	acpi_status status = AE_OK;
85	union acpi_operand_object *source_desc;
86	union acpi_operand_object *obj_desc = NULL;
87	struct acpi_namespace_node *node;
88	acpi_object_type entry_type;
89
90	ACPI_FUNCTION_TRACE(ex_resolve_node_to_value);
91
92	/*
93	 * The stack pointer points to a struct acpi_namespace_node (Node).  Get the
94	 * object that is attached to the Node.
95	 */
96	node = *object_ptr;
97	source_desc = acpi_ns_get_attached_object(node);
98	entry_type = acpi_ns_get_type((acpi_handle) node);
99
100	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Entry=%p SourceDesc=%p [%s]\n",
101			  node, source_desc,
102			  acpi_ut_get_type_name(entry_type)));
103
104	if ((entry_type == ACPI_TYPE_LOCAL_ALIAS) ||
105	    (entry_type == ACPI_TYPE_LOCAL_METHOD_ALIAS)) {
106
107		/* There is always exactly one level of indirection */
108
109		node = ACPI_CAST_PTR(struct acpi_namespace_node, node->object);
110		source_desc = acpi_ns_get_attached_object(node);
111		entry_type = acpi_ns_get_type((acpi_handle) node);
112		*object_ptr = node;
113	}
114
115	/*
116	 * Several object types require no further processing:
117	 * 1) Device/Thermal objects don't have a "real" subobject, return the Node
118	 * 2) Method locals and arguments have a pseudo-Node
119	 */
120	if ((entry_type == ACPI_TYPE_DEVICE) ||
121	    (entry_type == ACPI_TYPE_THERMAL) ||
122	    (node->flags & (ANOBJ_METHOD_ARG | ANOBJ_METHOD_LOCAL))) {
123		return_ACPI_STATUS(AE_OK);
124	}
125
126	if (!source_desc) {
127		ACPI_ERROR((AE_INFO, "No object attached to node %p", node));
128		return_ACPI_STATUS(AE_AML_NO_OPERAND);
129	}
130
131	/*
132	 * Action is based on the type of the Node, which indicates the type
133	 * of the attached object or pointer
134	 */
135	switch (entry_type) {
136	case ACPI_TYPE_PACKAGE:
137
138		if (ACPI_GET_OBJECT_TYPE(source_desc) != ACPI_TYPE_PACKAGE) {
139			ACPI_ERROR((AE_INFO, "Object not a Package, type %s",
140				    acpi_ut_get_object_type_name(source_desc)));
141			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
142		}
143
144		status = acpi_ds_get_package_arguments(source_desc);
145		if (ACPI_SUCCESS(status)) {
146
147			/* Return an additional reference to the object */
148
149			obj_desc = source_desc;
150			acpi_ut_add_reference(obj_desc);
151		}
152		break;
153
154	case ACPI_TYPE_BUFFER:
155
156		if (ACPI_GET_OBJECT_TYPE(source_desc) != ACPI_TYPE_BUFFER) {
157			ACPI_ERROR((AE_INFO, "Object not a Buffer, type %s",
158				    acpi_ut_get_object_type_name(source_desc)));
159			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
160		}
161
162		status = acpi_ds_get_buffer_arguments(source_desc);
163		if (ACPI_SUCCESS(status)) {
164
165			/* Return an additional reference to the object */
166
167			obj_desc = source_desc;
168			acpi_ut_add_reference(obj_desc);
169		}
170		break;
171
172	case ACPI_TYPE_STRING:
173
174		if (ACPI_GET_OBJECT_TYPE(source_desc) != ACPI_TYPE_STRING) {
175			ACPI_ERROR((AE_INFO, "Object not a String, type %s",
176				    acpi_ut_get_object_type_name(source_desc)));
177			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
178		}
179
180		/* Return an additional reference to the object */
181
182		obj_desc = source_desc;
183		acpi_ut_add_reference(obj_desc);
184		break;
185
186	case ACPI_TYPE_INTEGER:
187
188		if (ACPI_GET_OBJECT_TYPE(source_desc) != ACPI_TYPE_INTEGER) {
189			ACPI_ERROR((AE_INFO, "Object not a Integer, type %s",
190				    acpi_ut_get_object_type_name(source_desc)));
191			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
192		}
193
194		/* Return an additional reference to the object */
195
196		obj_desc = source_desc;
197		acpi_ut_add_reference(obj_desc);
198		break;
199
200	case ACPI_TYPE_BUFFER_FIELD:
201	case ACPI_TYPE_LOCAL_REGION_FIELD:
202	case ACPI_TYPE_LOCAL_BANK_FIELD:
203	case ACPI_TYPE_LOCAL_INDEX_FIELD:
204
205		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
206				  "FieldRead Node=%p SourceDesc=%p Type=%X\n",
207				  node, source_desc, entry_type));
208
209		status =
210		    acpi_ex_read_data_from_field(walk_state, source_desc,
211						 &obj_desc);
212		break;
213
214		/* For these objects, just return the object attached to the Node */
215
216	case ACPI_TYPE_MUTEX:
217	case ACPI_TYPE_METHOD:
218	case ACPI_TYPE_POWER:
219	case ACPI_TYPE_PROCESSOR:
220	case ACPI_TYPE_EVENT:
221	case ACPI_TYPE_REGION:
222
223		/* Return an additional reference to the object */
224
225		obj_desc = source_desc;
226		acpi_ut_add_reference(obj_desc);
227		break;
228
229		/* TYPE_ANY is untyped, and thus there is no object associated with it */
230
231	case ACPI_TYPE_ANY:
232
233		ACPI_ERROR((AE_INFO,
234			    "Untyped entry %p, no attached object!", node));
235
236		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);	/* Cannot be AE_TYPE */
237
238	case ACPI_TYPE_LOCAL_REFERENCE:
239
240		switch (source_desc->reference.opcode) {
241		case AML_LOAD_OP:
242
243			/* This is a ddb_handle */
244			/* Return an additional reference to the object */
245
246		case AML_REF_OF_OP:
247
248			obj_desc = source_desc;
249			acpi_ut_add_reference(obj_desc);
250			break;
251
252		default:
253			/* No named references are allowed here */
254
255			ACPI_ERROR((AE_INFO,
256				    "Unsupported Reference opcode %X (%s)",
257				    source_desc->reference.opcode,
258				    acpi_ps_get_opcode_name(source_desc->
259							    reference.opcode)));
260
261			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
262		}
263		break;
264
265	default:
266
267		/* Default case is for unknown types */
268
269		ACPI_ERROR((AE_INFO,
270			    "Node %p - Unknown object type %X",
271			    node, entry_type));
272
273		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
274
275	}			/* switch (entry_type) */
276
277	/* Return the object descriptor */
278
279	*object_ptr = (void *)obj_desc;
280	return_ACPI_STATUS(status);
281}
282