xref: /openbmc/linux/drivers/acpi/acpica/exresnte.c (revision afc98d90)
1 /******************************************************************************
2  *
3  * Module Name: exresnte - AML Interpreter object resolution
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2013, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acdispat.h"
47 #include "acinterp.h"
48 #include "acnamesp.h"
49 
50 #define _COMPONENT          ACPI_EXECUTER
51 ACPI_MODULE_NAME("exresnte")
52 
53 /*******************************************************************************
54  *
55  * FUNCTION:    acpi_ex_resolve_node_to_value
56  *
57  * PARAMETERS:  object_ptr      - Pointer to a location that contains
58  *                                a pointer to a NS node, and will receive a
59  *                                pointer to the resolved object.
60  *              walk_state      - Current state. Valid only if executing AML
61  *                                code. NULL if simply resolving an object
62  *
63  * RETURN:      Status
64  *
65  * DESCRIPTION: Resolve a Namespace node to a valued object
66  *
67  * Note: for some of the data types, the pointer attached to the Node
68  * can be either a pointer to an actual internal object or a pointer into the
69  * AML stream itself. These types are currently:
70  *
71  *      ACPI_TYPE_INTEGER
72  *      ACPI_TYPE_STRING
73  *      ACPI_TYPE_BUFFER
74  *      ACPI_TYPE_MUTEX
75  *      ACPI_TYPE_PACKAGE
76  *
77  ******************************************************************************/
78 acpi_status
79 acpi_ex_resolve_node_to_value(struct acpi_namespace_node **object_ptr,
80 			      struct acpi_walk_state *walk_state)
81 {
82 	acpi_status status = AE_OK;
83 	union acpi_operand_object *source_desc;
84 	union acpi_operand_object *obj_desc = NULL;
85 	struct acpi_namespace_node *node;
86 	acpi_object_type entry_type;
87 
88 	ACPI_FUNCTION_TRACE(ex_resolve_node_to_value);
89 
90 	/*
91 	 * The stack pointer points to a struct acpi_namespace_node (Node). Get the
92 	 * object that is attached to the Node.
93 	 */
94 	node = *object_ptr;
95 	source_desc = acpi_ns_get_attached_object(node);
96 	entry_type = acpi_ns_get_type((acpi_handle) node);
97 
98 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Entry=%p SourceDesc=%p [%s]\n",
99 			  node, source_desc,
100 			  acpi_ut_get_type_name(entry_type)));
101 
102 	if ((entry_type == ACPI_TYPE_LOCAL_ALIAS) ||
103 	    (entry_type == ACPI_TYPE_LOCAL_METHOD_ALIAS)) {
104 
105 		/* There is always exactly one level of indirection */
106 
107 		node = ACPI_CAST_PTR(struct acpi_namespace_node, node->object);
108 		source_desc = acpi_ns_get_attached_object(node);
109 		entry_type = acpi_ns_get_type((acpi_handle) node);
110 		*object_ptr = node;
111 	}
112 
113 	/*
114 	 * Several object types require no further processing:
115 	 * 1) Device/Thermal objects don't have a "real" subobject, return the Node
116 	 * 2) Method locals and arguments have a pseudo-Node
117 	 * 3) 10/2007: Added method type to assist with Package construction.
118 	 */
119 	if ((entry_type == ACPI_TYPE_DEVICE) ||
120 	    (entry_type == ACPI_TYPE_THERMAL) ||
121 	    (entry_type == ACPI_TYPE_METHOD) ||
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 [%4.4s] %p",
128 			    node->name.ascii, node));
129 		return_ACPI_STATUS(AE_AML_NO_OPERAND);
130 	}
131 
132 	/*
133 	 * Action is based on the type of the Node, which indicates the type
134 	 * of the attached object or pointer
135 	 */
136 	switch (entry_type) {
137 	case ACPI_TYPE_PACKAGE:
138 
139 		if (source_desc->common.type != ACPI_TYPE_PACKAGE) {
140 			ACPI_ERROR((AE_INFO, "Object not a Package, type %s",
141 				    acpi_ut_get_object_type_name(source_desc)));
142 			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
143 		}
144 
145 		status = acpi_ds_get_package_arguments(source_desc);
146 		if (ACPI_SUCCESS(status)) {
147 
148 			/* Return an additional reference to the object */
149 
150 			obj_desc = source_desc;
151 			acpi_ut_add_reference(obj_desc);
152 		}
153 		break;
154 
155 	case ACPI_TYPE_BUFFER:
156 
157 		if (source_desc->common.type != ACPI_TYPE_BUFFER) {
158 			ACPI_ERROR((AE_INFO, "Object not a Buffer, type %s",
159 				    acpi_ut_get_object_type_name(source_desc)));
160 			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
161 		}
162 
163 		status = acpi_ds_get_buffer_arguments(source_desc);
164 		if (ACPI_SUCCESS(status)) {
165 
166 			/* Return an additional reference to the object */
167 
168 			obj_desc = source_desc;
169 			acpi_ut_add_reference(obj_desc);
170 		}
171 		break;
172 
173 	case ACPI_TYPE_STRING:
174 
175 		if (source_desc->common.type != ACPI_TYPE_STRING) {
176 			ACPI_ERROR((AE_INFO, "Object not a String, type %s",
177 				    acpi_ut_get_object_type_name(source_desc)));
178 			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
179 		}
180 
181 		/* Return an additional reference to the object */
182 
183 		obj_desc = source_desc;
184 		acpi_ut_add_reference(obj_desc);
185 		break;
186 
187 	case ACPI_TYPE_INTEGER:
188 
189 		if (source_desc->common.type != ACPI_TYPE_INTEGER) {
190 			ACPI_ERROR((AE_INFO, "Object not a Integer, type %s",
191 				    acpi_ut_get_object_type_name(source_desc)));
192 			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
193 		}
194 
195 		/* Return an additional reference to the object */
196 
197 		obj_desc = source_desc;
198 		acpi_ut_add_reference(obj_desc);
199 		break;
200 
201 	case ACPI_TYPE_BUFFER_FIELD:
202 	case ACPI_TYPE_LOCAL_REGION_FIELD:
203 	case ACPI_TYPE_LOCAL_BANK_FIELD:
204 	case ACPI_TYPE_LOCAL_INDEX_FIELD:
205 
206 		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
207 				  "FieldRead Node=%p SourceDesc=%p Type=%X\n",
208 				  node, source_desc, entry_type));
209 
210 		status =
211 		    acpi_ex_read_data_from_field(walk_state, source_desc,
212 						 &obj_desc);
213 		break;
214 
215 		/* For these objects, just return the object attached to the Node */
216 
217 	case ACPI_TYPE_MUTEX:
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.class) {
241 		case ACPI_REFCLASS_TABLE:	/* This is a ddb_handle */
242 		case ACPI_REFCLASS_REFOF:
243 		case ACPI_REFCLASS_INDEX:
244 
245 			/* Return an additional reference to the object */
246 
247 			obj_desc = source_desc;
248 			acpi_ut_add_reference(obj_desc);
249 			break;
250 
251 		default:
252 
253 			/* No named references are allowed here */
254 
255 			ACPI_ERROR((AE_INFO,
256 				    "Unsupported Reference type 0x%X",
257 				    source_desc->reference.class));
258 
259 			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
260 		}
261 		break;
262 
263 	default:
264 
265 		/* Default case is for unknown types */
266 
267 		ACPI_ERROR((AE_INFO,
268 			    "Node %p - Unknown object type 0x%X",
269 			    node, entry_type));
270 
271 		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
272 
273 	}			/* switch (entry_type) */
274 
275 	/* Return the object descriptor */
276 
277 	*object_ptr = (void *)obj_desc;
278 	return_ACPI_STATUS(status);
279 }
280