xref: /openbmc/linux/drivers/acpi/acpica/nsload.c (revision d0e22329)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: nsload - namespace loading/expanding/contracting procedures
5  *
6  * Copyright (C) 2000 - 2018, Intel Corp.
7  *
8  *****************************************************************************/
9 
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acnamesp.h"
13 #include "acdispat.h"
14 #include "actables.h"
15 #include "acinterp.h"
16 
17 #define _COMPONENT          ACPI_NAMESPACE
18 ACPI_MODULE_NAME("nsload")
19 
20 /* Local prototypes */
21 #ifdef ACPI_FUTURE_IMPLEMENTATION
22 acpi_status acpi_ns_unload_namespace(acpi_handle handle);
23 
24 static acpi_status acpi_ns_delete_subtree(acpi_handle start_handle);
25 #endif
26 
27 /*******************************************************************************
28  *
29  * FUNCTION:    acpi_ns_load_table
30  *
31  * PARAMETERS:  table_index     - Index for table to be loaded
32  *              node            - Owning NS node
33  *
34  * RETURN:      Status
35  *
36  * DESCRIPTION: Load one ACPI table into the namespace
37  *
38  ******************************************************************************/
39 
40 acpi_status
41 acpi_ns_load_table(u32 table_index, struct acpi_namespace_node *node)
42 {
43 	acpi_status status;
44 
45 	ACPI_FUNCTION_TRACE(ns_load_table);
46 
47 	/* If table already loaded into namespace, just return */
48 
49 	if (acpi_tb_is_table_loaded(table_index)) {
50 		status = AE_ALREADY_EXISTS;
51 		goto unlock;
52 	}
53 
54 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
55 			  "**** Loading table into namespace ****\n"));
56 
57 	status = acpi_tb_allocate_owner_id(table_index);
58 	if (ACPI_FAILURE(status)) {
59 		goto unlock;
60 	}
61 
62 	/*
63 	 * Parse the table and load the namespace with all named
64 	 * objects found within. Control methods are NOT parsed
65 	 * at this time. In fact, the control methods cannot be
66 	 * parsed until the entire namespace is loaded, because
67 	 * if a control method makes a forward reference (call)
68 	 * to another control method, we can't continue parsing
69 	 * because we don't know how many arguments to parse next!
70 	 */
71 	status = acpi_ns_parse_table(table_index, node);
72 	if (ACPI_SUCCESS(status)) {
73 		acpi_tb_set_table_loaded_flag(table_index, TRUE);
74 	} else {
75 		/*
76 		 * On error, delete any namespace objects created by this table.
77 		 * We cannot initialize these objects, so delete them. There are
78 		 * a couple of expecially bad cases:
79 		 * AE_ALREADY_EXISTS - namespace collision.
80 		 * AE_NOT_FOUND - the target of a Scope operator does not
81 		 * exist. This target of Scope must already exist in the
82 		 * namespace, as per the ACPI specification.
83 		 */
84 		acpi_ns_delete_namespace_by_owner(acpi_gbl_root_table_list.
85 						  tables[table_index].owner_id);
86 
87 		acpi_tb_release_owner_id(table_index);
88 		return_ACPI_STATUS(status);
89 	}
90 
91 unlock:
92 	if (ACPI_FAILURE(status)) {
93 		return_ACPI_STATUS(status);
94 	}
95 
96 	/*
97 	 * Now we can parse the control methods. We always parse
98 	 * them here for a sanity check, and if configured for
99 	 * just-in-time parsing, we delete the control method
100 	 * parse trees.
101 	 */
102 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
103 			  "**** Begin Table Object Initialization\n"));
104 
105 	acpi_ex_enter_interpreter();
106 	status = acpi_ds_initialize_objects(table_index, node);
107 	acpi_ex_exit_interpreter();
108 
109 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
110 			  "**** Completed Table Object Initialization\n"));
111 
112 	/*
113 	 * This case handles the legacy option that groups all module-level
114 	 * code blocks together and defers execution until all of the tables
115 	 * are loaded. Execute all of these blocks at this time.
116 	 * Execute any module-level code that was detected during the table
117 	 * load phase.
118 	 *
119 	 * Note: this option is deprecated and will be eliminated in the
120 	 * future. Use of this option can cause problems with AML code that
121 	 * depends upon in-order immediate execution of module-level code.
122 	 */
123 	acpi_ns_exec_module_code_list();
124 	return_ACPI_STATUS(status);
125 }
126 
127 #ifdef ACPI_OBSOLETE_FUNCTIONS
128 /*******************************************************************************
129  *
130  * FUNCTION:    acpi_load_namespace
131  *
132  * PARAMETERS:  None
133  *
134  * RETURN:      Status
135  *
136  * DESCRIPTION: Load the name space from what ever is pointed to by DSDT.
137  *              (DSDT points to either the BIOS or a buffer.)
138  *
139  ******************************************************************************/
140 
141 acpi_status acpi_ns_load_namespace(void)
142 {
143 	acpi_status status;
144 
145 	ACPI_FUNCTION_TRACE(acpi_load_name_space);
146 
147 	/* There must be at least a DSDT installed */
148 
149 	if (acpi_gbl_DSDT == NULL) {
150 		ACPI_ERROR((AE_INFO, "DSDT is not in memory"));
151 		return_ACPI_STATUS(AE_NO_ACPI_TABLES);
152 	}
153 
154 	/*
155 	 * Load the namespace. The DSDT is required,
156 	 * but the SSDT and PSDT tables are optional.
157 	 */
158 	status = acpi_ns_load_table_by_type(ACPI_TABLE_ID_DSDT);
159 	if (ACPI_FAILURE(status)) {
160 		return_ACPI_STATUS(status);
161 	}
162 
163 	/* Ignore exceptions from these */
164 
165 	(void)acpi_ns_load_table_by_type(ACPI_TABLE_ID_SSDT);
166 	(void)acpi_ns_load_table_by_type(ACPI_TABLE_ID_PSDT);
167 
168 	ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
169 			      "ACPI Namespace successfully loaded at root %p\n",
170 			      acpi_gbl_root_node));
171 
172 	return_ACPI_STATUS(status);
173 }
174 #endif
175 
176 #ifdef ACPI_FUTURE_IMPLEMENTATION
177 /*******************************************************************************
178  *
179  * FUNCTION:    acpi_ns_delete_subtree
180  *
181  * PARAMETERS:  start_handle        - Handle in namespace where search begins
182  *
183  * RETURNS      Status
184  *
185  * DESCRIPTION: Walks the namespace starting at the given handle and deletes
186  *              all objects, entries, and scopes in the entire subtree.
187  *
188  *              Namespace/Interpreter should be locked or the subsystem should
189  *              be in shutdown before this routine is called.
190  *
191  ******************************************************************************/
192 
193 static acpi_status acpi_ns_delete_subtree(acpi_handle start_handle)
194 {
195 	acpi_status status;
196 	acpi_handle child_handle;
197 	acpi_handle parent_handle;
198 	acpi_handle next_child_handle;
199 	acpi_handle dummy;
200 	u32 level;
201 
202 	ACPI_FUNCTION_TRACE(ns_delete_subtree);
203 
204 	parent_handle = start_handle;
205 	child_handle = NULL;
206 	level = 1;
207 
208 	/*
209 	 * Traverse the tree of objects until we bubble back up
210 	 * to where we started.
211 	 */
212 	while (level > 0) {
213 
214 		/* Attempt to get the next object in this scope */
215 
216 		status = acpi_get_next_object(ACPI_TYPE_ANY, parent_handle,
217 					      child_handle, &next_child_handle);
218 
219 		child_handle = next_child_handle;
220 
221 		/* Did we get a new object? */
222 
223 		if (ACPI_SUCCESS(status)) {
224 
225 			/* Check if this object has any children */
226 
227 			if (ACPI_SUCCESS
228 			    (acpi_get_next_object
229 			     (ACPI_TYPE_ANY, child_handle, NULL, &dummy))) {
230 				/*
231 				 * There is at least one child of this object,
232 				 * visit the object
233 				 */
234 				level++;
235 				parent_handle = child_handle;
236 				child_handle = NULL;
237 			}
238 		} else {
239 			/*
240 			 * No more children in this object, go back up to
241 			 * the object's parent
242 			 */
243 			level--;
244 
245 			/* Delete all children now */
246 
247 			acpi_ns_delete_children(child_handle);
248 
249 			child_handle = parent_handle;
250 			status = acpi_get_parent(parent_handle, &parent_handle);
251 			if (ACPI_FAILURE(status)) {
252 				return_ACPI_STATUS(status);
253 			}
254 		}
255 	}
256 
257 	/* Now delete the starting object, and we are done */
258 
259 	acpi_ns_remove_node(child_handle);
260 	return_ACPI_STATUS(AE_OK);
261 }
262 
263 /*******************************************************************************
264  *
265  *  FUNCTION:       acpi_ns_unload_name_space
266  *
267  *  PARAMETERS:     handle          - Root of namespace subtree to be deleted
268  *
269  *  RETURN:         Status
270  *
271  *  DESCRIPTION:    Shrinks the namespace, typically in response to an undocking
272  *                  event. Deletes an entire subtree starting from (and
273  *                  including) the given handle.
274  *
275  ******************************************************************************/
276 
277 acpi_status acpi_ns_unload_namespace(acpi_handle handle)
278 {
279 	acpi_status status;
280 
281 	ACPI_FUNCTION_TRACE(ns_unload_name_space);
282 
283 	/* Parameter validation */
284 
285 	if (!acpi_gbl_root_node) {
286 		return_ACPI_STATUS(AE_NO_NAMESPACE);
287 	}
288 
289 	if (!handle) {
290 		return_ACPI_STATUS(AE_BAD_PARAMETER);
291 	}
292 
293 	/* This function does the real work */
294 
295 	status = acpi_ns_delete_subtree(handle);
296 	return_ACPI_STATUS(status);
297 }
298 #endif
299