xref: /openbmc/linux/drivers/acpi/acpica/exconfig.c (revision a89988a6)
1 /******************************************************************************
2  *
3  * Module Name: exconfig - Namespace reconfiguration (Load/Unload opcodes)
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2017, 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 "acinterp.h"
47 #include "acnamesp.h"
48 #include "actables.h"
49 #include "acdispat.h"
50 #include "acevents.h"
51 #include "amlcode.h"
52 
53 #define _COMPONENT          ACPI_EXECUTER
54 ACPI_MODULE_NAME("exconfig")
55 
56 /* Local prototypes */
57 static acpi_status
58 acpi_ex_add_table(u32 table_index, union acpi_operand_object **ddb_handle);
59 
60 static acpi_status
61 acpi_ex_region_read(union acpi_operand_object *obj_desc,
62 		    u32 length, u8 *buffer);
63 
64 /*******************************************************************************
65  *
66  * FUNCTION:    acpi_ex_add_table
67  *
68  * PARAMETERS:  table               - Pointer to raw table
69  *              parent_node         - Where to load the table (scope)
70  *              ddb_handle          - Where to return the table handle.
71  *
72  * RETURN:      Status
73  *
74  * DESCRIPTION: Common function to Install and Load an ACPI table with a
75  *              returned table handle.
76  *
77  ******************************************************************************/
78 
79 static acpi_status
80 acpi_ex_add_table(u32 table_index, union acpi_operand_object **ddb_handle)
81 {
82 	union acpi_operand_object *obj_desc;
83 
84 	ACPI_FUNCTION_TRACE(ex_add_table);
85 
86 	/* Create an object to be the table handle */
87 
88 	obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_REFERENCE);
89 	if (!obj_desc) {
90 		return_ACPI_STATUS(AE_NO_MEMORY);
91 	}
92 
93 	/* Init the table handle */
94 
95 	obj_desc->common.flags |= AOPOBJ_DATA_VALID;
96 	obj_desc->reference.class = ACPI_REFCLASS_TABLE;
97 	obj_desc->reference.value = table_index;
98 	*ddb_handle = obj_desc;
99 	return_ACPI_STATUS(AE_OK);
100 }
101 
102 /*******************************************************************************
103  *
104  * FUNCTION:    acpi_ex_load_table_op
105  *
106  * PARAMETERS:  walk_state          - Current state with operands
107  *              return_desc         - Where to store the return object
108  *
109  * RETURN:      Status
110  *
111  * DESCRIPTION: Load an ACPI table from the RSDT/XSDT
112  *
113  ******************************************************************************/
114 
115 acpi_status
116 acpi_ex_load_table_op(struct acpi_walk_state *walk_state,
117 		      union acpi_operand_object **return_desc)
118 {
119 	acpi_status status;
120 	union acpi_operand_object **operand = &walk_state->operands[0];
121 	struct acpi_namespace_node *parent_node;
122 	struct acpi_namespace_node *start_node;
123 	struct acpi_namespace_node *parameter_node = NULL;
124 	union acpi_operand_object *ddb_handle;
125 	u32 table_index;
126 
127 	ACPI_FUNCTION_TRACE(ex_load_table_op);
128 
129 	/* Find the ACPI table in the RSDT/XSDT */
130 
131 	acpi_ex_exit_interpreter();
132 	status = acpi_tb_find_table(operand[0]->string.pointer,
133 				    operand[1]->string.pointer,
134 				    operand[2]->string.pointer, &table_index);
135 	acpi_ex_enter_interpreter();
136 	if (ACPI_FAILURE(status)) {
137 		if (status != AE_NOT_FOUND) {
138 			return_ACPI_STATUS(status);
139 		}
140 
141 		/* Table not found, return an Integer=0 and AE_OK */
142 
143 		ddb_handle = acpi_ut_create_integer_object((u64) 0);
144 		if (!ddb_handle) {
145 			return_ACPI_STATUS(AE_NO_MEMORY);
146 		}
147 
148 		*return_desc = ddb_handle;
149 		return_ACPI_STATUS(AE_OK);
150 	}
151 
152 	/* Default nodes */
153 
154 	start_node = walk_state->scope_info->scope.node;
155 	parent_node = acpi_gbl_root_node;
156 
157 	/* root_path (optional parameter) */
158 
159 	if (operand[3]->string.length > 0) {
160 		/*
161 		 * Find the node referenced by the root_path_string. This is the
162 		 * location within the namespace where the table will be loaded.
163 		 */
164 		status = acpi_ns_get_node_unlocked(start_node,
165 						   operand[3]->string.pointer,
166 						   ACPI_NS_SEARCH_PARENT,
167 						   &parent_node);
168 		if (ACPI_FAILURE(status)) {
169 			return_ACPI_STATUS(status);
170 		}
171 	}
172 
173 	/* parameter_path (optional parameter) */
174 
175 	if (operand[4]->string.length > 0) {
176 		if ((operand[4]->string.pointer[0] != AML_ROOT_PREFIX) &&
177 		    (operand[4]->string.pointer[0] != AML_PARENT_PREFIX)) {
178 			/*
179 			 * Path is not absolute, so it will be relative to the node
180 			 * referenced by the root_path_string (or the NS root if omitted)
181 			 */
182 			start_node = parent_node;
183 		}
184 
185 		/* Find the node referenced by the parameter_path_string */
186 
187 		status = acpi_ns_get_node_unlocked(start_node,
188 						   operand[4]->string.pointer,
189 						   ACPI_NS_SEARCH_PARENT,
190 						   &parameter_node);
191 		if (ACPI_FAILURE(status)) {
192 			return_ACPI_STATUS(status);
193 		}
194 	}
195 
196 	/* Load the table into the namespace */
197 
198 	ACPI_INFO(("Dynamic OEM Table Load:"));
199 	acpi_ex_exit_interpreter();
200 	status = acpi_tb_load_table(table_index, parent_node);
201 	acpi_ex_enter_interpreter();
202 	if (ACPI_FAILURE(status)) {
203 		return_ACPI_STATUS(status);
204 	}
205 
206 	status = acpi_ex_add_table(table_index, &ddb_handle);
207 	if (ACPI_FAILURE(status)) {
208 		return_ACPI_STATUS(status);
209 	}
210 
211 	/* Parameter Data (optional) */
212 
213 	if (parameter_node) {
214 
215 		/* Store the parameter data into the optional parameter object */
216 
217 		status = acpi_ex_store(operand[5],
218 				       ACPI_CAST_PTR(union acpi_operand_object,
219 						     parameter_node),
220 				       walk_state);
221 		if (ACPI_FAILURE(status)) {
222 			(void)acpi_ex_unload_table(ddb_handle);
223 
224 			acpi_ut_remove_reference(ddb_handle);
225 			return_ACPI_STATUS(status);
226 		}
227 	}
228 
229 	*return_desc = ddb_handle;
230 	return_ACPI_STATUS(status);
231 }
232 
233 /*******************************************************************************
234  *
235  * FUNCTION:    acpi_ex_region_read
236  *
237  * PARAMETERS:  obj_desc        - Region descriptor
238  *              length          - Number of bytes to read
239  *              buffer          - Pointer to where to put the data
240  *
241  * RETURN:      Status
242  *
243  * DESCRIPTION: Read data from an operation region. The read starts from the
244  *              beginning of the region.
245  *
246  ******************************************************************************/
247 
248 static acpi_status
249 acpi_ex_region_read(union acpi_operand_object *obj_desc, u32 length, u8 *buffer)
250 {
251 	acpi_status status;
252 	u64 value;
253 	u32 region_offset = 0;
254 	u32 i;
255 
256 	/* Bytewise reads */
257 
258 	for (i = 0; i < length; i++) {
259 		status =
260 		    acpi_ev_address_space_dispatch(obj_desc, NULL, ACPI_READ,
261 						   region_offset, 8, &value);
262 		if (ACPI_FAILURE(status)) {
263 			return (status);
264 		}
265 
266 		*buffer = (u8)value;
267 		buffer++;
268 		region_offset++;
269 	}
270 
271 	return (AE_OK);
272 }
273 
274 /*******************************************************************************
275  *
276  * FUNCTION:    acpi_ex_load_op
277  *
278  * PARAMETERS:  obj_desc        - Region or Buffer/Field where the table will be
279  *                                obtained
280  *              target          - Where a handle to the table will be stored
281  *              walk_state      - Current state
282  *
283  * RETURN:      Status
284  *
285  * DESCRIPTION: Load an ACPI table from a field or operation region
286  *
287  * NOTE: Region Fields (Field, bank_field, index_fields) are resolved to buffer
288  *       objects before this code is reached.
289  *
290  *       If source is an operation region, it must refer to system_memory, as
291  *       per the ACPI specification.
292  *
293  ******************************************************************************/
294 
295 acpi_status
296 acpi_ex_load_op(union acpi_operand_object *obj_desc,
297 		union acpi_operand_object *target,
298 		struct acpi_walk_state *walk_state)
299 {
300 	union acpi_operand_object *ddb_handle;
301 	struct acpi_table_header *table_header;
302 	struct acpi_table_header *table;
303 	u32 table_index;
304 	acpi_status status;
305 	u32 length;
306 
307 	ACPI_FUNCTION_TRACE(ex_load_op);
308 
309 	/* Source Object can be either an op_region or a Buffer/Field */
310 
311 	switch (obj_desc->common.type) {
312 	case ACPI_TYPE_REGION:
313 
314 		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
315 				  "Load table from Region %p\n", obj_desc));
316 
317 		/* Region must be system_memory (from ACPI spec) */
318 
319 		if (obj_desc->region.space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY) {
320 			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
321 		}
322 
323 		/*
324 		 * If the Region Address and Length have not been previously
325 		 * evaluated, evaluate them now and save the results.
326 		 */
327 		if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
328 			status = acpi_ds_get_region_arguments(obj_desc);
329 			if (ACPI_FAILURE(status)) {
330 				return_ACPI_STATUS(status);
331 			}
332 		}
333 
334 		/* Get the table header first so we can get the table length */
335 
336 		table_header = ACPI_ALLOCATE(sizeof(struct acpi_table_header));
337 		if (!table_header) {
338 			return_ACPI_STATUS(AE_NO_MEMORY);
339 		}
340 
341 		status =
342 		    acpi_ex_region_read(obj_desc,
343 					sizeof(struct acpi_table_header),
344 					ACPI_CAST_PTR(u8, table_header));
345 		length = table_header->length;
346 		ACPI_FREE(table_header);
347 
348 		if (ACPI_FAILURE(status)) {
349 			return_ACPI_STATUS(status);
350 		}
351 
352 		/* Must have at least an ACPI table header */
353 
354 		if (length < sizeof(struct acpi_table_header)) {
355 			return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
356 		}
357 
358 		/*
359 		 * The original implementation simply mapped the table, with no copy.
360 		 * However, the memory region is not guaranteed to remain stable and
361 		 * we must copy the table to a local buffer. For example, the memory
362 		 * region is corrupted after suspend on some machines. Dynamically
363 		 * loaded tables are usually small, so this overhead is minimal.
364 		 *
365 		 * The latest implementation (5/2009) does not use a mapping at all.
366 		 * We use the low-level operation region interface to read the table
367 		 * instead of the obvious optimization of using a direct mapping.
368 		 * This maintains a consistent use of operation regions across the
369 		 * entire subsystem. This is important if additional processing must
370 		 * be performed in the (possibly user-installed) operation region
371 		 * handler. For example, acpi_exec and ASLTS depend on this.
372 		 */
373 
374 		/* Allocate a buffer for the table */
375 
376 		table = ACPI_ALLOCATE(length);
377 		if (!table) {
378 			return_ACPI_STATUS(AE_NO_MEMORY);
379 		}
380 
381 		/* Read the entire table */
382 
383 		status = acpi_ex_region_read(obj_desc, length,
384 					     ACPI_CAST_PTR(u8, table));
385 		if (ACPI_FAILURE(status)) {
386 			ACPI_FREE(table);
387 			return_ACPI_STATUS(status);
388 		}
389 		break;
390 
391 	case ACPI_TYPE_BUFFER:	/* Buffer or resolved region_field */
392 
393 		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
394 				  "Load table from Buffer or Field %p\n",
395 				  obj_desc));
396 
397 		/* Must have at least an ACPI table header */
398 
399 		if (obj_desc->buffer.length < sizeof(struct acpi_table_header)) {
400 			return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
401 		}
402 
403 		/* Get the actual table length from the table header */
404 
405 		table_header =
406 		    ACPI_CAST_PTR(struct acpi_table_header,
407 				  obj_desc->buffer.pointer);
408 		length = table_header->length;
409 
410 		/* Table cannot extend beyond the buffer */
411 
412 		if (length > obj_desc->buffer.length) {
413 			return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
414 		}
415 		if (length < sizeof(struct acpi_table_header)) {
416 			return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
417 		}
418 
419 		/*
420 		 * Copy the table from the buffer because the buffer could be
421 		 * modified or even deleted in the future
422 		 */
423 		table = ACPI_ALLOCATE(length);
424 		if (!table) {
425 			return_ACPI_STATUS(AE_NO_MEMORY);
426 		}
427 
428 		memcpy(table, table_header, length);
429 		break;
430 
431 	default:
432 
433 		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
434 	}
435 
436 	/* Install the new table into the local data structures */
437 
438 	ACPI_INFO(("Dynamic OEM Table Load:"));
439 	acpi_ex_exit_interpreter();
440 	status = acpi_tb_install_and_load_table(ACPI_PTR_TO_PHYSADDR(table),
441 						ACPI_TABLE_ORIGIN_INTERNAL_VIRTUAL,
442 						TRUE, &table_index);
443 	acpi_ex_enter_interpreter();
444 	if (ACPI_FAILURE(status)) {
445 
446 		/* Delete allocated table buffer */
447 
448 		ACPI_FREE(table);
449 		return_ACPI_STATUS(status);
450 	}
451 
452 	/*
453 	 * Add the table to the namespace.
454 	 *
455 	 * Note: Load the table objects relative to the root of the namespace.
456 	 * This appears to go against the ACPI specification, but we do it for
457 	 * compatibility with other ACPI implementations.
458 	 */
459 	status = acpi_ex_add_table(table_index, &ddb_handle);
460 	if (ACPI_FAILURE(status)) {
461 
462 		/* On error, table_ptr was deallocated above */
463 
464 		return_ACPI_STATUS(status);
465 	}
466 
467 	/* Store the ddb_handle into the Target operand */
468 
469 	status = acpi_ex_store(ddb_handle, target, walk_state);
470 	if (ACPI_FAILURE(status)) {
471 		(void)acpi_ex_unload_table(ddb_handle);
472 
473 		/* table_ptr was deallocated above */
474 
475 		acpi_ut_remove_reference(ddb_handle);
476 		return_ACPI_STATUS(status);
477 	}
478 
479 	/* Remove the reference by added by acpi_ex_store above */
480 
481 	acpi_ut_remove_reference(ddb_handle);
482 	return_ACPI_STATUS(status);
483 }
484 
485 /*******************************************************************************
486  *
487  * FUNCTION:    acpi_ex_unload_table
488  *
489  * PARAMETERS:  ddb_handle          - Handle to a previously loaded table
490  *
491  * RETURN:      Status
492  *
493  * DESCRIPTION: Unload an ACPI table
494  *
495  ******************************************************************************/
496 
497 acpi_status acpi_ex_unload_table(union acpi_operand_object *ddb_handle)
498 {
499 	acpi_status status = AE_OK;
500 	union acpi_operand_object *table_desc = ddb_handle;
501 	u32 table_index;
502 
503 	ACPI_FUNCTION_TRACE(ex_unload_table);
504 
505 	/*
506 	 * Temporarily emit a warning so that the ASL for the machine can be
507 	 * hopefully obtained. This is to say that the Unload() operator is
508 	 * extremely rare if not completely unused.
509 	 */
510 	ACPI_WARNING((AE_INFO, "Received request to unload an ACPI table"));
511 
512 	/*
513 	 * Validate the handle
514 	 * Although the handle is partially validated in acpi_ex_reconfiguration()
515 	 * when it calls acpi_ex_resolve_operands(), the handle is more completely
516 	 * validated here.
517 	 *
518 	 * Handle must be a valid operand object of type reference. Also, the
519 	 * ddb_handle must still be marked valid (table has not been previously
520 	 * unloaded)
521 	 */
522 	if ((!ddb_handle) ||
523 	    (ACPI_GET_DESCRIPTOR_TYPE(ddb_handle) != ACPI_DESC_TYPE_OPERAND) ||
524 	    (ddb_handle->common.type != ACPI_TYPE_LOCAL_REFERENCE) ||
525 	    (!(ddb_handle->common.flags & AOPOBJ_DATA_VALID))) {
526 		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
527 	}
528 
529 	/* Get the table index from the ddb_handle */
530 
531 	table_index = table_desc->reference.value;
532 
533 	/*
534 	 * Release the interpreter lock so that the table lock won't have
535 	 * strict order requirement against it.
536 	 */
537 	acpi_ex_exit_interpreter();
538 	status = acpi_tb_unload_table(table_index);
539 	acpi_ex_enter_interpreter();
540 
541 	/*
542 	 * Invalidate the handle. We do this because the handle may be stored
543 	 * in a named object and may not be actually deleted until much later.
544 	 */
545 	if (ACPI_SUCCESS(status)) {
546 		ddb_handle->common.flags &= ~AOPOBJ_DATA_VALID;
547 	}
548 	return_ACPI_STATUS(status);
549 }
550