xref: /openbmc/linux/drivers/acpi/acpica/tbxface.c (revision a44e4f3a)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: tbxface - ACPI table-oriented external interfaces
5  *
6  * Copyright (C) 2000 - 2019, Intel Corp.
7  *
8  *****************************************************************************/
9 
10 #define EXPORT_ACPI_INTERFACES
11 
12 #include <acpi/acpi.h>
13 #include "accommon.h"
14 #include "actables.h"
15 
16 #define _COMPONENT          ACPI_TABLES
17 ACPI_MODULE_NAME("tbxface")
18 
19 /*******************************************************************************
20  *
21  * FUNCTION:    acpi_allocate_root_table
22  *
23  * PARAMETERS:  initial_table_count - Size of initial_table_array, in number of
24  *                                    struct acpi_table_desc structures
25  *
26  * RETURN:      Status
27  *
28  * DESCRIPTION: Allocate a root table array. Used by iASL compiler and
29  *              acpi_initialize_tables.
30  *
31  ******************************************************************************/
32 acpi_status acpi_allocate_root_table(u32 initial_table_count)
33 {
34 
35 	acpi_gbl_root_table_list.max_table_count = initial_table_count;
36 	acpi_gbl_root_table_list.flags = ACPI_ROOT_ALLOW_RESIZE;
37 
38 	return (acpi_tb_resize_root_table_list());
39 }
40 
41 /*******************************************************************************
42  *
43  * FUNCTION:    acpi_initialize_tables
44  *
45  * PARAMETERS:  initial_table_array - Pointer to an array of pre-allocated
46  *                                    struct acpi_table_desc structures. If NULL, the
47  *                                    array is dynamically allocated.
48  *              initial_table_count - Size of initial_table_array, in number of
49  *                                    struct acpi_table_desc structures
50  *              allow_resize        - Flag to tell Table Manager if resize of
51  *                                    pre-allocated array is allowed. Ignored
52  *                                    if initial_table_array is NULL.
53  *
54  * RETURN:      Status
55  *
56  * DESCRIPTION: Initialize the table manager, get the RSDP and RSDT/XSDT.
57  *
58  * NOTE:        Allows static allocation of the initial table array in order
59  *              to avoid the use of dynamic memory in confined environments
60  *              such as the kernel boot sequence where it may not be available.
61  *
62  *              If the host OS memory managers are initialized, use NULL for
63  *              initial_table_array, and the table will be dynamically allocated.
64  *
65  ******************************************************************************/
66 
67 acpi_status ACPI_INIT_FUNCTION
68 acpi_initialize_tables(struct acpi_table_desc *initial_table_array,
69 		       u32 initial_table_count, u8 allow_resize)
70 {
71 	acpi_physical_address rsdp_address;
72 	acpi_status status;
73 
74 	ACPI_FUNCTION_TRACE(acpi_initialize_tables);
75 
76 	/*
77 	 * Setup the Root Table Array and allocate the table array
78 	 * if requested
79 	 */
80 	if (!initial_table_array) {
81 		status = acpi_allocate_root_table(initial_table_count);
82 		if (ACPI_FAILURE(status)) {
83 			return_ACPI_STATUS(status);
84 		}
85 	} else {
86 		/* Root Table Array has been statically allocated by the host */
87 
88 		memset(initial_table_array, 0,
89 		       (acpi_size)initial_table_count *
90 		       sizeof(struct acpi_table_desc));
91 
92 		acpi_gbl_root_table_list.tables = initial_table_array;
93 		acpi_gbl_root_table_list.max_table_count = initial_table_count;
94 		acpi_gbl_root_table_list.flags = ACPI_ROOT_ORIGIN_UNKNOWN;
95 		if (allow_resize) {
96 			acpi_gbl_root_table_list.flags |=
97 			    ACPI_ROOT_ALLOW_RESIZE;
98 		}
99 	}
100 
101 	/* Get the address of the RSDP */
102 
103 	rsdp_address = acpi_os_get_root_pointer();
104 	if (!rsdp_address) {
105 		return_ACPI_STATUS(AE_NOT_FOUND);
106 	}
107 
108 	/*
109 	 * Get the root table (RSDT or XSDT) and extract all entries to the local
110 	 * Root Table Array. This array contains the information of the RSDT/XSDT
111 	 * in a common, more usable format.
112 	 */
113 	status = acpi_tb_parse_root_table(rsdp_address);
114 	return_ACPI_STATUS(status);
115 }
116 
117 ACPI_EXPORT_SYMBOL_INIT(acpi_initialize_tables)
118 
119 /*******************************************************************************
120  *
121  * FUNCTION:    acpi_reallocate_root_table
122  *
123  * PARAMETERS:  None
124  *
125  * RETURN:      Status
126  *
127  * DESCRIPTION: Reallocate Root Table List into dynamic memory. Copies the
128  *              root list from the previously provided scratch area. Should
129  *              be called once dynamic memory allocation is available in the
130  *              kernel.
131  *
132  ******************************************************************************/
133 acpi_status ACPI_INIT_FUNCTION acpi_reallocate_root_table(void)
134 {
135 	acpi_status status;
136 	struct acpi_table_desc *table_desc;
137 	u32 i, j;
138 
139 	ACPI_FUNCTION_TRACE(acpi_reallocate_root_table);
140 
141 	/*
142 	 * If there are tables unverified, it is required to reallocate the
143 	 * root table list to clean up invalid table entries. Otherwise only
144 	 * reallocate the root table list if the host provided a static buffer
145 	 * for the table array in the call to acpi_initialize_tables().
146 	 */
147 	if ((acpi_gbl_root_table_list.flags & ACPI_ROOT_ORIGIN_ALLOCATED) &&
148 	    acpi_gbl_enable_table_validation) {
149 		return_ACPI_STATUS(AE_SUPPORT);
150 	}
151 
152 	(void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
153 
154 	/*
155 	 * Ensure OS early boot logic, which is required by some hosts. If the
156 	 * table state is reported to be wrong, developers should fix the
157 	 * issue by invoking acpi_put_table() for the reported table during the
158 	 * early stage.
159 	 */
160 	for (i = 0; i < acpi_gbl_root_table_list.current_table_count; ++i) {
161 		table_desc = &acpi_gbl_root_table_list.tables[i];
162 		if (table_desc->pointer) {
163 			ACPI_ERROR((AE_INFO,
164 				    "Table [%4.4s] is not invalidated during early boot stage",
165 				    table_desc->signature.ascii));
166 		}
167 	}
168 
169 	if (!acpi_gbl_enable_table_validation) {
170 		/*
171 		 * Now it's safe to do full table validation. We can do deferred
172 		 * table initialization here once the flag is set.
173 		 */
174 		acpi_gbl_enable_table_validation = TRUE;
175 		for (i = 0; i < acpi_gbl_root_table_list.current_table_count;
176 		     ++i) {
177 			table_desc = &acpi_gbl_root_table_list.tables[i];
178 			if (!(table_desc->flags & ACPI_TABLE_IS_VERIFIED)) {
179 				status =
180 				    acpi_tb_verify_temp_table(table_desc, NULL,
181 							      &j);
182 				if (ACPI_FAILURE(status)) {
183 					acpi_tb_uninstall_table(table_desc);
184 				}
185 			}
186 		}
187 	}
188 
189 	acpi_gbl_root_table_list.flags |= ACPI_ROOT_ALLOW_RESIZE;
190 	status = acpi_tb_resize_root_table_list();
191 	acpi_gbl_root_table_list.flags |= ACPI_ROOT_ORIGIN_ALLOCATED;
192 
193 	(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
194 	return_ACPI_STATUS(status);
195 }
196 
197 ACPI_EXPORT_SYMBOL_INIT(acpi_reallocate_root_table)
198 
199 /*******************************************************************************
200  *
201  * FUNCTION:    acpi_get_table_header
202  *
203  * PARAMETERS:  signature           - ACPI signature of needed table
204  *              instance            - Which instance (for SSDTs)
205  *              out_table_header    - The pointer to the table header to fill
206  *
207  * RETURN:      Status and pointer to mapped table header
208  *
209  * DESCRIPTION: Finds an ACPI table header.
210  *
211  * NOTE:        Caller is responsible in unmapping the header with
212  *              acpi_os_unmap_memory
213  *
214  ******************************************************************************/
215 acpi_status
216 acpi_get_table_header(char *signature,
217 		      u32 instance, struct acpi_table_header *out_table_header)
218 {
219 	u32 i;
220 	u32 j;
221 	struct acpi_table_header *header;
222 
223 	/* Parameter validation */
224 
225 	if (!signature || !out_table_header) {
226 		return (AE_BAD_PARAMETER);
227 	}
228 
229 	/* Walk the root table list */
230 
231 	for (i = 0, j = 0; i < acpi_gbl_root_table_list.current_table_count;
232 	     i++) {
233 		if (!ACPI_COMPARE_NAMESEG
234 		    (&(acpi_gbl_root_table_list.tables[i].signature),
235 		     signature)) {
236 			continue;
237 		}
238 
239 		if (++j < instance) {
240 			continue;
241 		}
242 
243 		if (!acpi_gbl_root_table_list.tables[i].pointer) {
244 			if ((acpi_gbl_root_table_list.tables[i].flags &
245 			     ACPI_TABLE_ORIGIN_MASK) ==
246 			    ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL) {
247 				header =
248 				    acpi_os_map_memory(acpi_gbl_root_table_list.
249 						       tables[i].address,
250 						       sizeof(struct
251 							      acpi_table_header));
252 				if (!header) {
253 					return (AE_NO_MEMORY);
254 				}
255 
256 				memcpy(out_table_header, header,
257 				       sizeof(struct acpi_table_header));
258 				acpi_os_unmap_memory(header,
259 						     sizeof(struct
260 							    acpi_table_header));
261 			} else {
262 				return (AE_NOT_FOUND);
263 			}
264 		} else {
265 			memcpy(out_table_header,
266 			       acpi_gbl_root_table_list.tables[i].pointer,
267 			       sizeof(struct acpi_table_header));
268 		}
269 		return (AE_OK);
270 	}
271 
272 	return (AE_NOT_FOUND);
273 }
274 
275 ACPI_EXPORT_SYMBOL(acpi_get_table_header)
276 
277 /*******************************************************************************
278  *
279  * FUNCTION:    acpi_get_table
280  *
281  * PARAMETERS:  signature           - ACPI signature of needed table
282  *              instance            - Which instance (for SSDTs)
283  *              out_table           - Where the pointer to the table is returned
284  *
285  * RETURN:      Status and pointer to the requested table
286  *
287  * DESCRIPTION: Finds and verifies an ACPI table. Table must be in the
288  *              RSDT/XSDT.
289  *              Note that an early stage acpi_get_table() call must be paired
290  *              with an early stage acpi_put_table() call. otherwise the table
291  *              pointer mapped by the early stage mapping implementation may be
292  *              erroneously unmapped by the late stage unmapping implementation
293  *              in an acpi_put_table() invoked during the late stage.
294  *
295  ******************************************************************************/
296 acpi_status
297 acpi_get_table(char *signature,
298 	       u32 instance, struct acpi_table_header ** out_table)
299 {
300 	u32 i;
301 	u32 j;
302 	acpi_status status = AE_NOT_FOUND;
303 	struct acpi_table_desc *table_desc;
304 
305 	/* Parameter validation */
306 
307 	if (!signature || !out_table) {
308 		return (AE_BAD_PARAMETER);
309 	}
310 
311 	/*
312 	 * Note that the following line is required by some OSPMs, they only
313 	 * check if the returned table is NULL instead of the returned status
314 	 * to determined if this function is succeeded.
315 	 */
316 	*out_table = NULL;
317 
318 	(void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
319 
320 	/* Walk the root table list */
321 
322 	for (i = 0, j = 0; i < acpi_gbl_root_table_list.current_table_count;
323 	     i++) {
324 		table_desc = &acpi_gbl_root_table_list.tables[i];
325 
326 		if (!ACPI_COMPARE_NAMESEG(&table_desc->signature, signature)) {
327 			continue;
328 		}
329 
330 		if (++j < instance) {
331 			continue;
332 		}
333 
334 		status = acpi_tb_get_table(table_desc, out_table);
335 		break;
336 	}
337 
338 	(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
339 	return (status);
340 }
341 
342 ACPI_EXPORT_SYMBOL(acpi_get_table)
343 
344 /*******************************************************************************
345  *
346  * FUNCTION:    acpi_put_table
347  *
348  * PARAMETERS:  table               - The pointer to the table
349  *
350  * RETURN:      None
351  *
352  * DESCRIPTION: Release a table returned by acpi_get_table() and its clones.
353  *              Note that it is not safe if this function was invoked after an
354  *              uninstallation happened to the original table descriptor.
355  *              Currently there is no OSPMs' requirement to handle such
356  *              situations.
357  *
358  ******************************************************************************/
359 void acpi_put_table(struct acpi_table_header *table)
360 {
361 	u32 i;
362 	struct acpi_table_desc *table_desc;
363 
364 	ACPI_FUNCTION_TRACE(acpi_put_table);
365 
366 	if (!table) {
367 		return_VOID;
368 	}
369 
370 	(void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
371 
372 	/* Walk the root table list */
373 
374 	for (i = 0; i < acpi_gbl_root_table_list.current_table_count; i++) {
375 		table_desc = &acpi_gbl_root_table_list.tables[i];
376 
377 		if (table_desc->pointer != table) {
378 			continue;
379 		}
380 
381 		acpi_tb_put_table(table_desc);
382 		break;
383 	}
384 
385 	(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
386 	return_VOID;
387 }
388 
389 ACPI_EXPORT_SYMBOL(acpi_put_table)
390 
391 /*******************************************************************************
392  *
393  * FUNCTION:    acpi_get_table_by_index
394  *
395  * PARAMETERS:  table_index         - Table index
396  *              out_table           - Where the pointer to the table is returned
397  *
398  * RETURN:      Status and pointer to the requested table
399  *
400  * DESCRIPTION: Obtain a table by an index into the global table list. Used
401  *              internally also.
402  *
403  ******************************************************************************/
404 acpi_status
405 acpi_get_table_by_index(u32 table_index, struct acpi_table_header **out_table)
406 {
407 	acpi_status status;
408 
409 	ACPI_FUNCTION_TRACE(acpi_get_table_by_index);
410 
411 	/* Parameter validation */
412 
413 	if (!out_table) {
414 		return_ACPI_STATUS(AE_BAD_PARAMETER);
415 	}
416 
417 	/*
418 	 * Note that the following line is required by some OSPMs, they only
419 	 * check if the returned table is NULL instead of the returned status
420 	 * to determined if this function is succeeded.
421 	 */
422 	*out_table = NULL;
423 
424 	(void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
425 
426 	/* Validate index */
427 
428 	if (table_index >= acpi_gbl_root_table_list.current_table_count) {
429 		status = AE_BAD_PARAMETER;
430 		goto unlock_and_exit;
431 	}
432 
433 	status =
434 	    acpi_tb_get_table(&acpi_gbl_root_table_list.tables[table_index],
435 			      out_table);
436 
437 unlock_and_exit:
438 	(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
439 	return_ACPI_STATUS(status);
440 }
441 
442 ACPI_EXPORT_SYMBOL(acpi_get_table_by_index)
443 
444 /*******************************************************************************
445  *
446  * FUNCTION:    acpi_install_table_handler
447  *
448  * PARAMETERS:  handler         - Table event handler
449  *              context         - Value passed to the handler on each event
450  *
451  * RETURN:      Status
452  *
453  * DESCRIPTION: Install a global table event handler.
454  *
455  ******************************************************************************/
456 acpi_status
457 acpi_install_table_handler(acpi_table_handler handler, void *context)
458 {
459 	acpi_status status;
460 
461 	ACPI_FUNCTION_TRACE(acpi_install_table_handler);
462 
463 	if (!handler) {
464 		return_ACPI_STATUS(AE_BAD_PARAMETER);
465 	}
466 
467 	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
468 	if (ACPI_FAILURE(status)) {
469 		return_ACPI_STATUS(status);
470 	}
471 
472 	/* Don't allow more than one handler */
473 
474 	if (acpi_gbl_table_handler) {
475 		status = AE_ALREADY_EXISTS;
476 		goto cleanup;
477 	}
478 
479 	/* Install the handler */
480 
481 	acpi_gbl_table_handler = handler;
482 	acpi_gbl_table_handler_context = context;
483 
484 cleanup:
485 	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
486 	return_ACPI_STATUS(status);
487 }
488 
489 ACPI_EXPORT_SYMBOL(acpi_install_table_handler)
490 
491 /*******************************************************************************
492  *
493  * FUNCTION:    acpi_remove_table_handler
494  *
495  * PARAMETERS:  handler         - Table event handler that was installed
496  *                                previously.
497  *
498  * RETURN:      Status
499  *
500  * DESCRIPTION: Remove a table event handler
501  *
502  ******************************************************************************/
503 acpi_status acpi_remove_table_handler(acpi_table_handler handler)
504 {
505 	acpi_status status;
506 
507 	ACPI_FUNCTION_TRACE(acpi_remove_table_handler);
508 
509 	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
510 	if (ACPI_FAILURE(status)) {
511 		return_ACPI_STATUS(status);
512 	}
513 
514 	/* Make sure that the installed handler is the same */
515 
516 	if (!handler || handler != acpi_gbl_table_handler) {
517 		status = AE_BAD_PARAMETER;
518 		goto cleanup;
519 	}
520 
521 	/* Remove the handler */
522 
523 	acpi_gbl_table_handler = NULL;
524 
525 cleanup:
526 	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
527 	return_ACPI_STATUS(status);
528 }
529 
530 ACPI_EXPORT_SYMBOL(acpi_remove_table_handler)
531