xref: /openbmc/linux/drivers/acpi/acpica/tbinstal.c (revision e983940270f10fe8551baf0098be76ea478294a3)
1 /******************************************************************************
2  *
3  * Module Name: tbinstal - ACPI table installation and removal
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2016, 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 "actables.h"
47 
48 #define _COMPONENT          ACPI_TABLES
49 ACPI_MODULE_NAME("tbinstal")
50 
51 /* Local prototypes */
52 static u8
53 acpi_tb_compare_tables(struct acpi_table_desc *table_desc, u32 table_index);
54 
55 /*******************************************************************************
56  *
57  * FUNCTION:    acpi_tb_compare_tables
58  *
59  * PARAMETERS:  table_desc          - Table 1 descriptor to be compared
60  *              table_index         - Index of table 2 to be compared
61  *
62  * RETURN:      TRUE if both tables are identical.
63  *
64  * DESCRIPTION: This function compares a table with another table that has
65  *              already been installed in the root table list.
66  *
67  ******************************************************************************/
68 
69 static u8
70 acpi_tb_compare_tables(struct acpi_table_desc *table_desc, u32 table_index)
71 {
72 	acpi_status status = AE_OK;
73 	u8 is_identical;
74 	struct acpi_table_header *table;
75 	u32 table_length;
76 	u8 table_flags;
77 
78 	status =
79 	    acpi_tb_acquire_table(&acpi_gbl_root_table_list.tables[table_index],
80 				  &table, &table_length, &table_flags);
81 	if (ACPI_FAILURE(status)) {
82 		return (FALSE);
83 	}
84 
85 	/*
86 	 * Check for a table match on the entire table length,
87 	 * not just the header.
88 	 */
89 	is_identical = (u8)((table_desc->length != table_length ||
90 			     memcmp(table_desc->pointer, table, table_length)) ?
91 			    FALSE : TRUE);
92 
93 	/* Release the acquired table */
94 
95 	acpi_tb_release_table(table, table_length, table_flags);
96 	return (is_identical);
97 }
98 
99 /*******************************************************************************
100  *
101  * FUNCTION:    acpi_tb_install_table_with_override
102  *
103  * PARAMETERS:  new_table_desc          - New table descriptor to install
104  *              override                - Whether override should be performed
105  *              table_index             - Where the table index is returned
106  *
107  * RETURN:      None
108  *
109  * DESCRIPTION: Install an ACPI table into the global data structure. The
110  *              table override mechanism is called to allow the host
111  *              OS to replace any table before it is installed in the root
112  *              table array.
113  *
114  ******************************************************************************/
115 
116 void
117 acpi_tb_install_table_with_override(struct acpi_table_desc *new_table_desc,
118 				    u8 override, u32 *table_index)
119 {
120 	u32 i;
121 	acpi_status status;
122 
123 	status = acpi_tb_get_next_table_descriptor(&i, NULL);
124 	if (ACPI_FAILURE(status)) {
125 		return;
126 	}
127 
128 	/*
129 	 * ACPI Table Override:
130 	 *
131 	 * Before we install the table, let the host OS override it with a new
132 	 * one if desired. Any table within the RSDT/XSDT can be replaced,
133 	 * including the DSDT which is pointed to by the FADT.
134 	 */
135 	if (override) {
136 		acpi_tb_override_table(new_table_desc);
137 	}
138 
139 	acpi_tb_init_table_descriptor(&acpi_gbl_root_table_list.tables[i],
140 				      new_table_desc->address,
141 				      new_table_desc->flags,
142 				      new_table_desc->pointer);
143 
144 	acpi_tb_print_table_header(new_table_desc->address,
145 				   new_table_desc->pointer);
146 
147 	/* This synchronizes acpi_gbl_dsdt_index */
148 
149 	*table_index = i;
150 
151 	/* Set the global integer width (based upon revision of the DSDT) */
152 
153 	if (i == acpi_gbl_dsdt_index) {
154 		acpi_ut_set_integer_width(new_table_desc->pointer->revision);
155 	}
156 }
157 
158 /*******************************************************************************
159  *
160  * FUNCTION:    acpi_tb_install_standard_table
161  *
162  * PARAMETERS:  address             - Address of the table (might be a virtual
163  *                                    address depending on the table_flags)
164  *              flags               - Flags for the table
165  *              reload              - Whether reload should be performed
166  *              override            - Whether override should be performed
167  *              table_index         - Where the table index is returned
168  *
169  * RETURN:      Status
170  *
171  * DESCRIPTION: This function is called to verify and install an ACPI table.
172  *              When this function is called by "Load" or "LoadTable" opcodes,
173  *              or by acpi_load_table() API, the "Reload" parameter is set.
174  *              After sucessfully returning from this function, table is
175  *              "INSTALLED" but not "VALIDATED".
176  *
177  ******************************************************************************/
178 
179 acpi_status
180 acpi_tb_install_standard_table(acpi_physical_address address,
181 			       u8 flags,
182 			       u8 reload, u8 override, u32 *table_index)
183 {
184 	u32 i;
185 	acpi_status status = AE_OK;
186 	struct acpi_table_desc new_table_desc;
187 
188 	ACPI_FUNCTION_TRACE(tb_install_standard_table);
189 
190 	/* Acquire a temporary table descriptor for validation */
191 
192 	status = acpi_tb_acquire_temp_table(&new_table_desc, address, flags);
193 	if (ACPI_FAILURE(status)) {
194 		ACPI_ERROR((AE_INFO,
195 			    "Could not acquire table length at %8.8X%8.8X",
196 			    ACPI_FORMAT_UINT64(address)));
197 		return_ACPI_STATUS(status);
198 	}
199 
200 	/*
201 	 * Optionally do not load any SSDTs from the RSDT/XSDT. This can
202 	 * be useful for debugging ACPI problems on some machines.
203 	 */
204 	if (!reload &&
205 	    acpi_gbl_disable_ssdt_table_install &&
206 	    ACPI_COMPARE_NAME(&new_table_desc.signature, ACPI_SIG_SSDT)) {
207 		ACPI_INFO(("Ignoring installation of %4.4s at %8.8X%8.8X",
208 			   new_table_desc.signature.ascii,
209 			   ACPI_FORMAT_UINT64(address)));
210 		goto release_and_exit;
211 	}
212 
213 	/* Validate and verify a table before installation */
214 
215 	status = acpi_tb_verify_temp_table(&new_table_desc, NULL);
216 	if (ACPI_FAILURE(status)) {
217 		goto release_and_exit;
218 	}
219 
220 	if (reload) {
221 		/*
222 		 * Validate the incoming table signature.
223 		 *
224 		 * 1) Originally, we checked the table signature for "SSDT" or "PSDT".
225 		 * 2) We added support for OEMx tables, signature "OEM".
226 		 * 3) Valid tables were encountered with a null signature, so we just
227 		 *    gave up on validating the signature, (05/2008).
228 		 * 4) We encountered non-AML tables such as the MADT, which caused
229 		 *    interpreter errors and kernel faults. So now, we once again allow
230 		 *    only "SSDT", "OEMx", and now, also a null signature. (05/2011).
231 		 */
232 		if ((new_table_desc.signature.ascii[0] != 0x00) &&
233 		    (!ACPI_COMPARE_NAME
234 		     (&new_table_desc.signature, ACPI_SIG_SSDT))
235 		    && (strncmp(new_table_desc.signature.ascii, "OEM", 3))) {
236 			ACPI_BIOS_ERROR((AE_INFO,
237 					 "Table has invalid signature [%4.4s] (0x%8.8X), "
238 					 "must be SSDT or OEMx",
239 					 acpi_ut_valid_nameseg(new_table_desc.
240 							       signature.
241 							       ascii) ?
242 					 new_table_desc.signature.
243 					 ascii : "????",
244 					 new_table_desc.signature.integer));
245 
246 			status = AE_BAD_SIGNATURE;
247 			goto release_and_exit;
248 		}
249 
250 		/* Check if table is already registered */
251 
252 		for (i = 0; i < acpi_gbl_root_table_list.current_table_count;
253 		     ++i) {
254 			/*
255 			 * Check for a table match on the entire table length,
256 			 * not just the header.
257 			 */
258 			if (!acpi_tb_compare_tables(&new_table_desc, i)) {
259 				continue;
260 			}
261 
262 			/*
263 			 * Note: the current mechanism does not unregister a table if it is
264 			 * dynamically unloaded. The related namespace entries are deleted,
265 			 * but the table remains in the root table list.
266 			 *
267 			 * The assumption here is that the number of different tables that
268 			 * will be loaded is actually small, and there is minimal overhead
269 			 * in just keeping the table in case it is needed again.
270 			 *
271 			 * If this assumption changes in the future (perhaps on large
272 			 * machines with many table load/unload operations), tables will
273 			 * need to be unregistered when they are unloaded, and slots in the
274 			 * root table list should be reused when empty.
275 			 */
276 			if (acpi_gbl_root_table_list.tables[i].flags &
277 			    ACPI_TABLE_IS_LOADED) {
278 
279 				/* Table is still loaded, this is an error */
280 
281 				status = AE_ALREADY_EXISTS;
282 				goto release_and_exit;
283 			} else {
284 				/*
285 				 * Table was unloaded, allow it to be reloaded.
286 				 * As we are going to return AE_OK to the caller, we should
287 				 * take the responsibility of freeing the input descriptor.
288 				 * Refill the input descriptor to ensure
289 				 * acpi_tb_install_table_with_override() can be called again to
290 				 * indicate the re-installation.
291 				 */
292 				acpi_tb_uninstall_table(&new_table_desc);
293 				*table_index = i;
294 				return_ACPI_STATUS(AE_OK);
295 			}
296 		}
297 	}
298 
299 	/* Add the table to the global root table list */
300 
301 	acpi_tb_install_table_with_override(&new_table_desc, override,
302 					    table_index);
303 
304 	/* Invoke table handler if present */
305 
306 	if (acpi_gbl_table_handler) {
307 		(void)acpi_gbl_table_handler(ACPI_TABLE_EVENT_INSTALL,
308 					     new_table_desc.pointer,
309 					     acpi_gbl_table_handler_context);
310 	}
311 
312 release_and_exit:
313 
314 	/* Release the temporary table descriptor */
315 
316 	acpi_tb_release_temp_table(&new_table_desc);
317 	return_ACPI_STATUS(status);
318 }
319 
320 /*******************************************************************************
321  *
322  * FUNCTION:    acpi_tb_override_table
323  *
324  * PARAMETERS:  old_table_desc      - Validated table descriptor to be
325  *                                    overridden
326  *
327  * RETURN:      None
328  *
329  * DESCRIPTION: Attempt table override by calling the OSL override functions.
330  *              Note: If the table is overridden, then the entire new table
331  *              is acquired and returned by this function.
332  *              Before/after invocation, the table descriptor is in a state
333  *              that is "VALIDATED".
334  *
335  ******************************************************************************/
336 
337 void acpi_tb_override_table(struct acpi_table_desc *old_table_desc)
338 {
339 	acpi_status status;
340 	char *override_type;
341 	struct acpi_table_desc new_table_desc;
342 	struct acpi_table_header *table;
343 	acpi_physical_address address;
344 	u32 length;
345 
346 	/* (1) Attempt logical override (returns a logical address) */
347 
348 	status = acpi_os_table_override(old_table_desc->pointer, &table);
349 	if (ACPI_SUCCESS(status) && table) {
350 		acpi_tb_acquire_temp_table(&new_table_desc,
351 					   ACPI_PTR_TO_PHYSADDR(table),
352 					   ACPI_TABLE_ORIGIN_EXTERNAL_VIRTUAL);
353 		override_type = "Logical";
354 		goto finish_override;
355 	}
356 
357 	/* (2) Attempt physical override (returns a physical address) */
358 
359 	status = acpi_os_physical_table_override(old_table_desc->pointer,
360 						 &address, &length);
361 	if (ACPI_SUCCESS(status) && address && length) {
362 		acpi_tb_acquire_temp_table(&new_table_desc, address,
363 					   ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL);
364 		override_type = "Physical";
365 		goto finish_override;
366 	}
367 
368 	return;			/* There was no override */
369 
370 finish_override:
371 
372 	/* Validate and verify a table before overriding */
373 
374 	status = acpi_tb_verify_temp_table(&new_table_desc, NULL);
375 	if (ACPI_FAILURE(status)) {
376 		return;
377 	}
378 
379 	ACPI_INFO(("%4.4s 0x%8.8X%8.8X"
380 		   " %s table override, new table: 0x%8.8X%8.8X",
381 		   old_table_desc->signature.ascii,
382 		   ACPI_FORMAT_UINT64(old_table_desc->address),
383 		   override_type, ACPI_FORMAT_UINT64(new_table_desc.address)));
384 
385 	/* We can now uninstall the original table */
386 
387 	acpi_tb_uninstall_table(old_table_desc);
388 
389 	/*
390 	 * Replace the original table descriptor and keep its state as
391 	 * "VALIDATED".
392 	 */
393 	acpi_tb_init_table_descriptor(old_table_desc, new_table_desc.address,
394 				      new_table_desc.flags,
395 				      new_table_desc.pointer);
396 	acpi_tb_validate_temp_table(old_table_desc);
397 
398 	/* Release the temporary table descriptor */
399 
400 	acpi_tb_release_temp_table(&new_table_desc);
401 }
402 
403 /*******************************************************************************
404  *
405  * FUNCTION:    acpi_tb_uninstall_table
406  *
407  * PARAMETERS:  table_desc          - Table descriptor
408  *
409  * RETURN:      None
410  *
411  * DESCRIPTION: Delete one internal ACPI table
412  *
413  ******************************************************************************/
414 
415 void acpi_tb_uninstall_table(struct acpi_table_desc *table_desc)
416 {
417 
418 	ACPI_FUNCTION_TRACE(tb_uninstall_table);
419 
420 	/* Table must be installed */
421 
422 	if (!table_desc->address) {
423 		return_VOID;
424 	}
425 
426 	acpi_tb_invalidate_table(table_desc);
427 
428 	if ((table_desc->flags & ACPI_TABLE_ORIGIN_MASK) ==
429 	    ACPI_TABLE_ORIGIN_INTERNAL_VIRTUAL) {
430 		ACPI_FREE(ACPI_PHYSADDR_TO_PTR(table_desc->address));
431 	}
432 
433 	table_desc->address = ACPI_PTR_TO_PHYSADDR(NULL);
434 	return_VOID;
435 }
436