xref: /openbmc/linux/drivers/acpi/acpica/nsload.c (revision ba61bb17)
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 #ifndef ACPI_NO_METHOD_EXECUTION
28 /*******************************************************************************
29  *
30  * FUNCTION:    acpi_ns_load_table
31  *
32  * PARAMETERS:  table_index     - Index for table to be loaded
33  *              node            - Owning NS node
34  *
35  * RETURN:      Status
36  *
37  * DESCRIPTION: Load one ACPI table into the namespace
38  *
39  ******************************************************************************/
40 
41 acpi_status
42 acpi_ns_load_table(u32 table_index, struct acpi_namespace_node *node)
43 {
44 	acpi_status status;
45 
46 	ACPI_FUNCTION_TRACE(ns_load_table);
47 
48 	/* If table already loaded into namespace, just return */
49 
50 	if (acpi_tb_is_table_loaded(table_index)) {
51 		status = AE_ALREADY_EXISTS;
52 		goto unlock;
53 	}
54 
55 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
56 			  "**** Loading table into namespace ****\n"));
57 
58 	status = acpi_tb_allocate_owner_id(table_index);
59 	if (ACPI_FAILURE(status)) {
60 		goto unlock;
61 	}
62 
63 	/*
64 	 * Parse the table and load the namespace with all named
65 	 * objects found within. Control methods are NOT parsed
66 	 * at this time. In fact, the control methods cannot be
67 	 * parsed until the entire namespace is loaded, because
68 	 * if a control method makes a forward reference (call)
69 	 * to another control method, we can't continue parsing
70 	 * because we don't know how many arguments to parse next!
71 	 */
72 	status = acpi_ns_parse_table(table_index, node);
73 	if (ACPI_SUCCESS(status)) {
74 		acpi_tb_set_table_loaded_flag(table_index, TRUE);
75 	} else {
76 		/*
77 		 * On error, delete any namespace objects created by this table.
78 		 * We cannot initialize these objects, so delete them. There are
79 		 * a couple of expecially bad cases:
80 		 * AE_ALREADY_EXISTS - namespace collision.
81 		 * AE_NOT_FOUND - the target of a Scope operator does not
82 		 * exist. This target of Scope must already exist in the
83 		 * namespace, as per the ACPI specification.
84 		 */
85 		acpi_ns_delete_namespace_by_owner(acpi_gbl_root_table_list.
86 						  tables[table_index].owner_id);
87 
88 		acpi_tb_release_owner_id(table_index);
89 		return_ACPI_STATUS(status);
90 	}
91 
92 unlock:
93 	if (ACPI_FAILURE(status)) {
94 		return_ACPI_STATUS(status);
95 	}
96 
97 	/*
98 	 * Now we can parse the control methods. We always parse
99 	 * them here for a sanity check, and if configured for
100 	 * just-in-time parsing, we delete the control method
101 	 * parse trees.
102 	 */
103 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
104 			  "**** Begin Table Object Initialization\n"));
105 
106 	acpi_ex_enter_interpreter();
107 	status = acpi_ds_initialize_objects(table_index, node);
108 	acpi_ex_exit_interpreter();
109 
110 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
111 			  "**** Completed Table Object Initialization\n"));
112 
113 	/*
114 	 * This case handles the legacy option that groups all module-level
115 	 * code blocks together and defers execution until all of the tables
116 	 * are loaded. Execute all of these blocks at this time.
117 	 * Execute any module-level code that was detected during the table
118 	 * load phase.
119 	 *
120 	 * Note: this option is deprecated and will be eliminated in the
121 	 * future. Use of this option can cause problems with AML code that
122 	 * depends upon in-order immediate execution of module-level code.
123 	 */
124 	acpi_ns_exec_module_code_list();
125 	return_ACPI_STATUS(status);
126 }
127 
128 #ifdef ACPI_OBSOLETE_FUNCTIONS
129 /*******************************************************************************
130  *
131  * FUNCTION:    acpi_load_namespace
132  *
133  * PARAMETERS:  None
134  *
135  * RETURN:      Status
136  *
137  * DESCRIPTION: Load the name space from what ever is pointed to by DSDT.
138  *              (DSDT points to either the BIOS or a buffer.)
139  *
140  ******************************************************************************/
141 
142 acpi_status acpi_ns_load_namespace(void)
143 {
144 	acpi_status status;
145 
146 	ACPI_FUNCTION_TRACE(acpi_load_name_space);
147 
148 	/* There must be at least a DSDT installed */
149 
150 	if (acpi_gbl_DSDT == NULL) {
151 		ACPI_ERROR((AE_INFO, "DSDT is not in memory"));
152 		return_ACPI_STATUS(AE_NO_ACPI_TABLES);
153 	}
154 
155 	/*
156 	 * Load the namespace. The DSDT is required,
157 	 * but the SSDT and PSDT tables are optional.
158 	 */
159 	status = acpi_ns_load_table_by_type(ACPI_TABLE_ID_DSDT);
160 	if (ACPI_FAILURE(status)) {
161 		return_ACPI_STATUS(status);
162 	}
163 
164 	/* Ignore exceptions from these */
165 
166 	(void)acpi_ns_load_table_by_type(ACPI_TABLE_ID_SSDT);
167 	(void)acpi_ns_load_table_by_type(ACPI_TABLE_ID_PSDT);
168 
169 	ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
170 			      "ACPI Namespace successfully loaded at root %p\n",
171 			      acpi_gbl_root_node));
172 
173 	return_ACPI_STATUS(status);
174 }
175 #endif
176 
177 #ifdef ACPI_FUTURE_IMPLEMENTATION
178 /*******************************************************************************
179  *
180  * FUNCTION:    acpi_ns_delete_subtree
181  *
182  * PARAMETERS:  start_handle        - Handle in namespace where search begins
183  *
184  * RETURNS      Status
185  *
186  * DESCRIPTION: Walks the namespace starting at the given handle and deletes
187  *              all objects, entries, and scopes in the entire subtree.
188  *
189  *              Namespace/Interpreter should be locked or the subsystem should
190  *              be in shutdown before this routine is called.
191  *
192  ******************************************************************************/
193 
194 static acpi_status acpi_ns_delete_subtree(acpi_handle start_handle)
195 {
196 	acpi_status status;
197 	acpi_handle child_handle;
198 	acpi_handle parent_handle;
199 	acpi_handle next_child_handle;
200 	acpi_handle dummy;
201 	u32 level;
202 
203 	ACPI_FUNCTION_TRACE(ns_delete_subtree);
204 
205 	parent_handle = start_handle;
206 	child_handle = NULL;
207 	level = 1;
208 
209 	/*
210 	 * Traverse the tree of objects until we bubble back up
211 	 * to where we started.
212 	 */
213 	while (level > 0) {
214 
215 		/* Attempt to get the next object in this scope */
216 
217 		status = acpi_get_next_object(ACPI_TYPE_ANY, parent_handle,
218 					      child_handle, &next_child_handle);
219 
220 		child_handle = next_child_handle;
221 
222 		/* Did we get a new object? */
223 
224 		if (ACPI_SUCCESS(status)) {
225 
226 			/* Check if this object has any children */
227 
228 			if (ACPI_SUCCESS
229 			    (acpi_get_next_object
230 			     (ACPI_TYPE_ANY, child_handle, NULL, &dummy))) {
231 				/*
232 				 * There is at least one child of this object,
233 				 * visit the object
234 				 */
235 				level++;
236 				parent_handle = child_handle;
237 				child_handle = NULL;
238 			}
239 		} else {
240 			/*
241 			 * No more children in this object, go back up to
242 			 * the object's parent
243 			 */
244 			level--;
245 
246 			/* Delete all children now */
247 
248 			acpi_ns_delete_children(child_handle);
249 
250 			child_handle = parent_handle;
251 			status = acpi_get_parent(parent_handle, &parent_handle);
252 			if (ACPI_FAILURE(status)) {
253 				return_ACPI_STATUS(status);
254 			}
255 		}
256 	}
257 
258 	/* Now delete the starting object, and we are done */
259 
260 	acpi_ns_remove_node(child_handle);
261 	return_ACPI_STATUS(AE_OK);
262 }
263 
264 /*******************************************************************************
265  *
266  *  FUNCTION:       acpi_ns_unload_name_space
267  *
268  *  PARAMETERS:     handle          - Root of namespace subtree to be deleted
269  *
270  *  RETURN:         Status
271  *
272  *  DESCRIPTION:    Shrinks the namespace, typically in response to an undocking
273  *                  event. Deletes an entire subtree starting from (and
274  *                  including) the given handle.
275  *
276  ******************************************************************************/
277 
278 acpi_status acpi_ns_unload_namespace(acpi_handle handle)
279 {
280 	acpi_status status;
281 
282 	ACPI_FUNCTION_TRACE(ns_unload_name_space);
283 
284 	/* Parameter validation */
285 
286 	if (!acpi_gbl_root_node) {
287 		return_ACPI_STATUS(AE_NO_NAMESPACE);
288 	}
289 
290 	if (!handle) {
291 		return_ACPI_STATUS(AE_BAD_PARAMETER);
292 	}
293 
294 	/* This function does the real work */
295 
296 	status = acpi_ns_delete_subtree(handle);
297 	return_ACPI_STATUS(status);
298 }
299 #endif
300 #endif
301