xref: /openbmc/linux/drivers/acpi/acpica/nsparse.c (revision 69fad28c)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: nsparse - namespace interface to AML parser
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 "acparser.h"
14 #include "acdispat.h"
15 #include "actables.h"
16 #include "acinterp.h"
17 
18 #define _COMPONENT          ACPI_NAMESPACE
19 ACPI_MODULE_NAME("nsparse")
20 
21 /*******************************************************************************
22  *
23  * FUNCTION:    ns_execute_table
24  *
25  * PARAMETERS:  table_desc      - An ACPI table descriptor for table to parse
26  *              start_node      - Where to enter the table into the namespace
27  *
28  * RETURN:      Status
29  *
30  * DESCRIPTION: Load ACPI/AML table by executing the entire table as a single
31  *              large control method.
32  *
33  * NOTE: The point of this is to execute any module-level code in-place
34  * as the table is parsed. Some AML code depends on this behavior.
35  *
36  * It is a run-time option at this time, but will eventually become
37  * the default.
38  *
39  * Note: This causes the table to only have a single-pass parse.
40  * However, this is compatible with other ACPI implementations.
41  *
42  ******************************************************************************/
43 acpi_status
44 acpi_ns_execute_table(u32 table_index, struct acpi_namespace_node *start_node)
45 {
46 	acpi_status status;
47 	struct acpi_table_header *table;
48 	acpi_owner_id owner_id;
49 	struct acpi_evaluate_info *info = NULL;
50 	u32 aml_length;
51 	u8 *aml_start;
52 	union acpi_operand_object *method_obj = NULL;
53 
54 	ACPI_FUNCTION_TRACE(ns_execute_table);
55 
56 	status = acpi_get_table_by_index(table_index, &table);
57 	if (ACPI_FAILURE(status)) {
58 		return_ACPI_STATUS(status);
59 	}
60 
61 	/* Table must consist of at least a complete header */
62 
63 	if (table->length < sizeof(struct acpi_table_header)) {
64 		return_ACPI_STATUS(AE_BAD_HEADER);
65 	}
66 
67 	aml_start = (u8 *)table + sizeof(struct acpi_table_header);
68 	aml_length = table->length - sizeof(struct acpi_table_header);
69 
70 	status = acpi_tb_get_owner_id(table_index, &owner_id);
71 	if (ACPI_FAILURE(status)) {
72 		return_ACPI_STATUS(status);
73 	}
74 
75 	/* Create, initialize, and link a new temporary method object */
76 
77 	method_obj = acpi_ut_create_internal_object(ACPI_TYPE_METHOD);
78 	if (!method_obj) {
79 		return_ACPI_STATUS(AE_NO_MEMORY);
80 	}
81 
82 	/* Allocate the evaluation information block */
83 
84 	info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
85 	if (!info) {
86 		status = AE_NO_MEMORY;
87 		goto cleanup;
88 	}
89 
90 	ACPI_DEBUG_PRINT_RAW((ACPI_DB_PARSE,
91 			      "%s: Create table pseudo-method for [%4.4s] @%p, method %p\n",
92 			      ACPI_GET_FUNCTION_NAME, table->signature, table,
93 			      method_obj));
94 
95 	method_obj->method.aml_start = aml_start;
96 	method_obj->method.aml_length = aml_length;
97 	method_obj->method.owner_id = owner_id;
98 	method_obj->method.info_flags |= ACPI_METHOD_MODULE_LEVEL;
99 
100 	info->pass_number = ACPI_IMODE_EXECUTE;
101 	info->node = start_node;
102 	info->obj_desc = method_obj;
103 	info->node_flags = info->node->flags;
104 	info->full_pathname = acpi_ns_get_normalized_pathname(info->node, TRUE);
105 	if (!info->full_pathname) {
106 		status = AE_NO_MEMORY;
107 		goto cleanup;
108 	}
109 
110 	/* Optional object evaluation log */
111 
112 	ACPI_DEBUG_PRINT_RAW((ACPI_DB_EVALUATION,
113 			      "%-26s:  (Definition Block level)\n",
114 			      "Module-level evaluation"));
115 
116 	status = acpi_ps_execute_table(info);
117 
118 	/* Optional object evaluation log */
119 
120 	ACPI_DEBUG_PRINT_RAW((ACPI_DB_EVALUATION,
121 			      "%-26s:  (Definition Block level)\n",
122 			      "Module-level complete"));
123 
124 cleanup:
125 	if (info) {
126 		ACPI_FREE(info->full_pathname);
127 		info->full_pathname = NULL;
128 	}
129 	ACPI_FREE(info);
130 	acpi_ut_remove_reference(method_obj);
131 	return_ACPI_STATUS(status);
132 }
133 
134 /*******************************************************************************
135  *
136  * FUNCTION:    ns_one_complete_parse
137  *
138  * PARAMETERS:  pass_number             - 1 or 2
139  *              table_desc              - The table to be parsed.
140  *
141  * RETURN:      Status
142  *
143  * DESCRIPTION: Perform one complete parse of an ACPI/AML table.
144  *
145  ******************************************************************************/
146 
147 acpi_status
148 acpi_ns_one_complete_parse(u32 pass_number,
149 			   u32 table_index,
150 			   struct acpi_namespace_node *start_node)
151 {
152 	union acpi_parse_object *parse_root;
153 	acpi_status status;
154 	u32 aml_length;
155 	u8 *aml_start;
156 	struct acpi_walk_state *walk_state;
157 	struct acpi_table_header *table;
158 	acpi_owner_id owner_id;
159 
160 	ACPI_FUNCTION_TRACE(ns_one_complete_parse);
161 
162 	status = acpi_get_table_by_index(table_index, &table);
163 	if (ACPI_FAILURE(status)) {
164 		return_ACPI_STATUS(status);
165 	}
166 
167 	/* Table must consist of at least a complete header */
168 
169 	if (table->length < sizeof(struct acpi_table_header)) {
170 		return_ACPI_STATUS(AE_BAD_HEADER);
171 	}
172 
173 	aml_start = (u8 *)table + sizeof(struct acpi_table_header);
174 	aml_length = table->length - sizeof(struct acpi_table_header);
175 
176 	status = acpi_tb_get_owner_id(table_index, &owner_id);
177 	if (ACPI_FAILURE(status)) {
178 		return_ACPI_STATUS(status);
179 	}
180 
181 	/* Create and init a Root Node */
182 
183 	parse_root = acpi_ps_create_scope_op(aml_start);
184 	if (!parse_root) {
185 		return_ACPI_STATUS(AE_NO_MEMORY);
186 	}
187 
188 	/* Create and initialize a new walk state */
189 
190 	walk_state = acpi_ds_create_walk_state(owner_id, NULL, NULL, NULL);
191 	if (!walk_state) {
192 		acpi_ps_free_op(parse_root);
193 		return_ACPI_STATUS(AE_NO_MEMORY);
194 	}
195 
196 	status = acpi_ds_init_aml_walk(walk_state, parse_root, NULL,
197 				       aml_start, aml_length, NULL,
198 				       (u8)pass_number);
199 	if (ACPI_FAILURE(status)) {
200 		acpi_ds_delete_walk_state(walk_state);
201 		goto cleanup;
202 	}
203 
204 	/* Found OSDT table, enable the namespace override feature */
205 
206 	if (ACPI_COMPARE_NAME(table->signature, ACPI_SIG_OSDT) &&
207 	    pass_number == ACPI_IMODE_LOAD_PASS1) {
208 		walk_state->namespace_override = TRUE;
209 	}
210 
211 	/* start_node is the default location to load the table */
212 
213 	if (start_node && start_node != acpi_gbl_root_node) {
214 		status =
215 		    acpi_ds_scope_stack_push(start_node, ACPI_TYPE_METHOD,
216 					     walk_state);
217 		if (ACPI_FAILURE(status)) {
218 			acpi_ds_delete_walk_state(walk_state);
219 			goto cleanup;
220 		}
221 	}
222 
223 	/* Parse the AML */
224 
225 	ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
226 			  "*PARSE* pass %u parse\n", pass_number));
227 	acpi_ex_enter_interpreter();
228 	status = acpi_ps_parse_aml(walk_state);
229 	acpi_ex_exit_interpreter();
230 
231 cleanup:
232 	acpi_ps_delete_parse_tree(parse_root);
233 	return_ACPI_STATUS(status);
234 }
235 
236 /*******************************************************************************
237  *
238  * FUNCTION:    acpi_ns_parse_table
239  *
240  * PARAMETERS:  table_desc      - An ACPI table descriptor for table to parse
241  *              start_node      - Where to enter the table into the namespace
242  *
243  * RETURN:      Status
244  *
245  * DESCRIPTION: Parse AML within an ACPI table and return a tree of ops
246  *
247  ******************************************************************************/
248 
249 acpi_status
250 acpi_ns_parse_table(u32 table_index, struct acpi_namespace_node *start_node)
251 {
252 	acpi_status status;
253 
254 	ACPI_FUNCTION_TRACE(ns_parse_table);
255 
256 	if (acpi_gbl_execute_tables_as_methods) {
257 		/*
258 		 * This case executes the AML table as one large control method.
259 		 * The point of this is to execute any module-level code in-place
260 		 * as the table is parsed. Some AML code depends on this behavior.
261 		 *
262 		 * It is a run-time option at this time, but will eventually become
263 		 * the default.
264 		 *
265 		 * Note: This causes the table to only have a single-pass parse.
266 		 * However, this is compatible with other ACPI implementations.
267 		 */
268 		ACPI_DEBUG_PRINT_RAW((ACPI_DB_PARSE,
269 				      "%s: **** Start table execution pass\n",
270 				      ACPI_GET_FUNCTION_NAME));
271 
272 		status = acpi_ns_execute_table(table_index, start_node);
273 		if (ACPI_FAILURE(status)) {
274 			return_ACPI_STATUS(status);
275 		}
276 	} else {
277 		/*
278 		 * AML Parse, pass 1
279 		 *
280 		 * In this pass, we load most of the namespace. Control methods
281 		 * are not parsed until later. A parse tree is not created.
282 		 * Instead, each Parser Op subtree is deleted when it is finished.
283 		 * This saves a great deal of memory, and allows a small cache of
284 		 * parse objects to service the entire parse. The second pass of
285 		 * the parse then performs another complete parse of the AML.
286 		 */
287 		ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "**** Start pass 1\n"));
288 
289 		status = acpi_ns_one_complete_parse(ACPI_IMODE_LOAD_PASS1,
290 						    table_index, start_node);
291 		if (ACPI_FAILURE(status)) {
292 			return_ACPI_STATUS(status);
293 		}
294 
295 		/*
296 		 * AML Parse, pass 2
297 		 *
298 		 * In this pass, we resolve forward references and other things
299 		 * that could not be completed during the first pass.
300 		 * Another complete parse of the AML is performed, but the
301 		 * overhead of this is compensated for by the fact that the
302 		 * parse objects are all cached.
303 		 */
304 		ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "**** Start pass 2\n"));
305 		status = acpi_ns_one_complete_parse(ACPI_IMODE_LOAD_PASS2,
306 						    table_index, start_node);
307 		if (ACPI_FAILURE(status)) {
308 			return_ACPI_STATUS(status);
309 		}
310 	}
311 
312 	return_ACPI_STATUS(status);
313 }
314