xref: /openbmc/linux/drivers/acpi/acpica/nsload.c (revision 3db55767)
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 - 2023, 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 especially 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 	return_ACPI_STATUS(status);
113 }
114 
115 #ifdef ACPI_OBSOLETE_FUNCTIONS
116 /*******************************************************************************
117  *
118  * FUNCTION:    acpi_load_namespace
119  *
120  * PARAMETERS:  None
121  *
122  * RETURN:      Status
123  *
124  * DESCRIPTION: Load the name space from what ever is pointed to by DSDT.
125  *              (DSDT points to either the BIOS or a buffer.)
126  *
127  ******************************************************************************/
128 
129 acpi_status acpi_ns_load_namespace(void)
130 {
131 	acpi_status status;
132 
133 	ACPI_FUNCTION_TRACE(acpi_load_name_space);
134 
135 	/* There must be at least a DSDT installed */
136 
137 	if (acpi_gbl_DSDT == NULL) {
138 		ACPI_ERROR((AE_INFO, "DSDT is not in memory"));
139 		return_ACPI_STATUS(AE_NO_ACPI_TABLES);
140 	}
141 
142 	/*
143 	 * Load the namespace. The DSDT is required,
144 	 * but the SSDT and PSDT tables are optional.
145 	 */
146 	status = acpi_ns_load_table_by_type(ACPI_TABLE_ID_DSDT);
147 	if (ACPI_FAILURE(status)) {
148 		return_ACPI_STATUS(status);
149 	}
150 
151 	/* Ignore exceptions from these */
152 
153 	(void)acpi_ns_load_table_by_type(ACPI_TABLE_ID_SSDT);
154 	(void)acpi_ns_load_table_by_type(ACPI_TABLE_ID_PSDT);
155 
156 	ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
157 			      "ACPI Namespace successfully loaded at root %p\n",
158 			      acpi_gbl_root_node));
159 
160 	return_ACPI_STATUS(status);
161 }
162 #endif
163 
164 #ifdef ACPI_FUTURE_IMPLEMENTATION
165 /*******************************************************************************
166  *
167  * FUNCTION:    acpi_ns_delete_subtree
168  *
169  * PARAMETERS:  start_handle        - Handle in namespace where search begins
170  *
171  * RETURNS      Status
172  *
173  * DESCRIPTION: Walks the namespace starting at the given handle and deletes
174  *              all objects, entries, and scopes in the entire subtree.
175  *
176  *              Namespace/Interpreter should be locked or the subsystem should
177  *              be in shutdown before this routine is called.
178  *
179  ******************************************************************************/
180 
181 static acpi_status acpi_ns_delete_subtree(acpi_handle start_handle)
182 {
183 	acpi_status status;
184 	acpi_handle child_handle;
185 	acpi_handle parent_handle;
186 	acpi_handle next_child_handle;
187 	acpi_handle dummy;
188 	u32 level;
189 
190 	ACPI_FUNCTION_TRACE(ns_delete_subtree);
191 
192 	parent_handle = start_handle;
193 	child_handle = NULL;
194 	level = 1;
195 
196 	/*
197 	 * Traverse the tree of objects until we bubble back up
198 	 * to where we started.
199 	 */
200 	while (level > 0) {
201 
202 		/* Attempt to get the next object in this scope */
203 
204 		status = acpi_get_next_object(ACPI_TYPE_ANY, parent_handle,
205 					      child_handle, &next_child_handle);
206 
207 		child_handle = next_child_handle;
208 
209 		/* Did we get a new object? */
210 
211 		if (ACPI_SUCCESS(status)) {
212 
213 			/* Check if this object has any children */
214 
215 			if (ACPI_SUCCESS
216 			    (acpi_get_next_object
217 			     (ACPI_TYPE_ANY, child_handle, NULL, &dummy))) {
218 				/*
219 				 * There is at least one child of this object,
220 				 * visit the object
221 				 */
222 				level++;
223 				parent_handle = child_handle;
224 				child_handle = NULL;
225 			}
226 		} else {
227 			/*
228 			 * No more children in this object, go back up to
229 			 * the object's parent
230 			 */
231 			level--;
232 
233 			/* Delete all children now */
234 
235 			acpi_ns_delete_children(child_handle);
236 
237 			child_handle = parent_handle;
238 			status = acpi_get_parent(parent_handle, &parent_handle);
239 			if (ACPI_FAILURE(status)) {
240 				return_ACPI_STATUS(status);
241 			}
242 		}
243 	}
244 
245 	/* Now delete the starting object, and we are done */
246 
247 	acpi_ns_remove_node(child_handle);
248 	return_ACPI_STATUS(AE_OK);
249 }
250 
251 /*******************************************************************************
252  *
253  *  FUNCTION:       acpi_ns_unload_name_space
254  *
255  *  PARAMETERS:     handle          - Root of namespace subtree to be deleted
256  *
257  *  RETURN:         Status
258  *
259  *  DESCRIPTION:    Shrinks the namespace, typically in response to an undocking
260  *                  event. Deletes an entire subtree starting from (and
261  *                  including) the given handle.
262  *
263  ******************************************************************************/
264 
265 acpi_status acpi_ns_unload_namespace(acpi_handle handle)
266 {
267 	acpi_status status;
268 
269 	ACPI_FUNCTION_TRACE(ns_unload_name_space);
270 
271 	/* Parameter validation */
272 
273 	if (!acpi_gbl_root_node) {
274 		return_ACPI_STATUS(AE_NO_NAMESPACE);
275 	}
276 
277 	if (!handle) {
278 		return_ACPI_STATUS(AE_BAD_PARAMETER);
279 	}
280 
281 	/* This function does the real work */
282 
283 	status = acpi_ns_delete_subtree(handle);
284 	return_ACPI_STATUS(status);
285 }
286 #endif
287