Merge master.kernel.org:/home/rmk/linux-2.6-serial
[pandora-kernel.git] / drivers / acpi / tables / tbget.c
1 /******************************************************************************
2  *
3  * Module Name: tbget - ACPI Table get* routines
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2006, R. Byron Moore
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 <acpi/actables.h>
46
47 #define _COMPONENT          ACPI_TABLES
48 ACPI_MODULE_NAME("tbget")
49
50 /* Local prototypes */
51 static acpi_status
52 acpi_tb_get_this_table(struct acpi_pointer *address,
53                        struct acpi_table_header *header,
54                        struct acpi_table_desc *table_info);
55
56 static acpi_status
57 acpi_tb_table_override(struct acpi_table_header *header,
58                        struct acpi_table_desc *table_info);
59
60 /*******************************************************************************
61  *
62  * FUNCTION:    acpi_tb_get_table
63  *
64  * PARAMETERS:  Address             - Address of table to retrieve.  Can be
65  *                                    Logical or Physical
66  *              table_info          - Where table info is returned
67  *
68  * RETURN:      None
69  *
70  * DESCRIPTION: Get entire table of unknown size.
71  *
72  ******************************************************************************/
73
74 acpi_status
75 acpi_tb_get_table(struct acpi_pointer *address,
76                   struct acpi_table_desc *table_info)
77 {
78         acpi_status status;
79         struct acpi_table_header header;
80
81         ACPI_FUNCTION_TRACE(tb_get_table);
82
83         /* Get the header in order to get signature and table size */
84
85         status = acpi_tb_get_table_header(address, &header);
86         if (ACPI_FAILURE(status)) {
87                 return_ACPI_STATUS(status);
88         }
89
90         /* Get the entire table */
91
92         status = acpi_tb_get_table_body(address, &header, table_info);
93         if (ACPI_FAILURE(status)) {
94                 ACPI_EXCEPTION((AE_INFO, status,
95                                 "Could not get ACPI table (size %X)",
96                                 header.length));
97                 return_ACPI_STATUS(status);
98         }
99
100         return_ACPI_STATUS(AE_OK);
101 }
102
103 /*******************************************************************************
104  *
105  * FUNCTION:    acpi_tb_get_table_header
106  *
107  * PARAMETERS:  Address             - Address of table to retrieve.  Can be
108  *                                    Logical or Physical
109  *              return_header       - Where the table header is returned
110  *
111  * RETURN:      Status
112  *
113  * DESCRIPTION: Get an ACPI table header.  Works in both physical or virtual
114  *              addressing mode.  Works with both physical or logical pointers.
115  *              Table is either copied or mapped, depending on the pointer
116  *              type and mode of the processor.
117  *
118  ******************************************************************************/
119
120 acpi_status
121 acpi_tb_get_table_header(struct acpi_pointer *address,
122                          struct acpi_table_header *return_header)
123 {
124         acpi_status status = AE_OK;
125         struct acpi_table_header *header = NULL;
126
127         ACPI_FUNCTION_TRACE(tb_get_table_header);
128
129         /*
130          * Flags contains the current processor mode (Virtual or Physical
131          * addressing) The pointer_type is either Logical or Physical
132          */
133         switch (address->pointer_type) {
134         case ACPI_PHYSMODE_PHYSPTR:
135         case ACPI_LOGMODE_LOGPTR:
136
137                 /* Pointer matches processor mode, copy the header */
138
139                 ACPI_MEMCPY(return_header, address->pointer.logical,
140                             sizeof(struct acpi_table_header));
141                 break;
142
143         case ACPI_LOGMODE_PHYSPTR:
144
145                 /* Create a logical address for the physical pointer */
146
147                 status = acpi_os_map_memory(address->pointer.physical,
148                                             sizeof(struct acpi_table_header),
149                                             (void *)&header);
150                 if (ACPI_FAILURE(status)) {
151                         ACPI_ERROR((AE_INFO,
152                                     "Could not map memory at %8.8X%8.8X for table header",
153                                     ACPI_FORMAT_UINT64(address->pointer.
154                                                        physical)));
155                         return_ACPI_STATUS(status);
156                 }
157
158                 /* Copy header and delete mapping */
159
160                 ACPI_MEMCPY(return_header, header,
161                             sizeof(struct acpi_table_header));
162                 acpi_os_unmap_memory(header, sizeof(struct acpi_table_header));
163                 break;
164
165         default:
166
167                 ACPI_ERROR((AE_INFO, "Invalid address flags %X",
168                             address->pointer_type));
169                 return_ACPI_STATUS(AE_BAD_PARAMETER);
170         }
171
172         ACPI_DEBUG_PRINT((ACPI_DB_TABLES, "Table Signature: [%4.4s]\n",
173                           return_header->signature));
174
175         return_ACPI_STATUS(AE_OK);
176 }
177
178 /*******************************************************************************
179  *
180  * FUNCTION:    acpi_tb_get_table_body
181  *
182  * PARAMETERS:  Address             - Address of table to retrieve.  Can be
183  *                                    Logical or Physical
184  *              Header              - Header of the table to retrieve
185  *              table_info          - Where the table info is returned
186  *
187  * RETURN:      Status
188  *
189  * DESCRIPTION: Get an entire ACPI table with support to allow the host OS to
190  *              replace the table with a newer version (table override.)
191  *              Works in both physical or virtual
192  *              addressing mode.  Works with both physical or logical pointers.
193  *              Table is either copied or mapped, depending on the pointer
194  *              type and mode of the processor.
195  *
196  ******************************************************************************/
197
198 acpi_status
199 acpi_tb_get_table_body(struct acpi_pointer *address,
200                        struct acpi_table_header *header,
201                        struct acpi_table_desc *table_info)
202 {
203         acpi_status status;
204
205         ACPI_FUNCTION_TRACE(tb_get_table_body);
206
207         if (!table_info || !address) {
208                 return_ACPI_STATUS(AE_BAD_PARAMETER);
209         }
210
211         /* Attempt table override. */
212
213         status = acpi_tb_table_override(header, table_info);
214         if (ACPI_SUCCESS(status)) {
215
216                 /* Table was overridden by the host OS */
217
218                 return_ACPI_STATUS(status);
219         }
220
221         /* No override, get the original table */
222
223         status = acpi_tb_get_this_table(address, header, table_info);
224         return_ACPI_STATUS(status);
225 }
226
227 /*******************************************************************************
228  *
229  * FUNCTION:    acpi_tb_table_override
230  *
231  * PARAMETERS:  Header              - Pointer to table header
232  *              table_info          - Return info if table is overridden
233  *
234  * RETURN:      None
235  *
236  * DESCRIPTION: Attempts override of current table with a new one if provided
237  *              by the host OS.
238  *
239  ******************************************************************************/
240
241 static acpi_status
242 acpi_tb_table_override(struct acpi_table_header *header,
243                        struct acpi_table_desc *table_info)
244 {
245         struct acpi_table_header *new_table;
246         acpi_status status;
247         struct acpi_pointer address;
248
249         ACPI_FUNCTION_TRACE(tb_table_override);
250
251         /*
252          * The OSL will examine the header and decide whether to override this
253          * table.  If it decides to override, a table will be returned in new_table,
254          * which we will then copy.
255          */
256         status = acpi_os_table_override(header, &new_table);
257         if (ACPI_FAILURE(status)) {
258
259                 /* Some severe error from the OSL, but we basically ignore it */
260
261                 ACPI_EXCEPTION((AE_INFO, status,
262                                 "Could not override ACPI table"));
263                 return_ACPI_STATUS(status);
264         }
265
266         if (!new_table) {
267
268                 /* No table override */
269
270                 return_ACPI_STATUS(AE_NO_ACPI_TABLES);
271         }
272
273         /*
274          * We have a new table to override the old one.  Get a copy of
275          * the new one.  We know that the new table has a logical pointer.
276          */
277         address.pointer_type = ACPI_LOGICAL_POINTER | ACPI_LOGICAL_ADDRESSING;
278         address.pointer.logical = new_table;
279
280         status = acpi_tb_get_this_table(&address, new_table, table_info);
281         if (ACPI_FAILURE(status)) {
282                 ACPI_EXCEPTION((AE_INFO, status, "Could not copy ACPI table"));
283                 return_ACPI_STATUS(status);
284         }
285
286         /* Copy the table info */
287
288         ACPI_INFO((AE_INFO, "Table [%4.4s] replaced by host OS",
289                    table_info->pointer->signature));
290
291         return_ACPI_STATUS(AE_OK);
292 }
293
294 /*******************************************************************************
295  *
296  * FUNCTION:    acpi_tb_get_this_table
297  *
298  * PARAMETERS:  Address             - Address of table to retrieve.  Can be
299  *                                    Logical or Physical
300  *              Header              - Header of the table to retrieve
301  *              table_info          - Where the table info is returned
302  *
303  * RETURN:      Status
304  *
305  * DESCRIPTION: Get an entire ACPI table.  Works in both physical or virtual
306  *              addressing mode.  Works with both physical or logical pointers.
307  *              Table is either copied or mapped, depending on the pointer
308  *              type and mode of the processor.
309  *
310  ******************************************************************************/
311
312 static acpi_status
313 acpi_tb_get_this_table(struct acpi_pointer *address,
314                        struct acpi_table_header *header,
315                        struct acpi_table_desc *table_info)
316 {
317         struct acpi_table_header *full_table = NULL;
318         u8 allocation;
319         acpi_status status = AE_OK;
320
321         ACPI_FUNCTION_TRACE(tb_get_this_table);
322
323         /* Validate minimum length */
324
325         if (header->length < sizeof(struct acpi_table_header)) {
326                 ACPI_ERROR((AE_INFO,
327                             "Table length (%X) is smaller than minimum (%X)",
328                             header->length, sizeof(struct acpi_table_header)));
329
330                 return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
331         }
332
333         /*
334          * Flags contains the current processor mode (Virtual or Physical
335          * addressing) The pointer_type is either Logical or Physical
336          */
337         switch (address->pointer_type) {
338         case ACPI_PHYSMODE_PHYSPTR:
339         case ACPI_LOGMODE_LOGPTR:
340
341                 /* Pointer matches processor mode, copy the table to a new buffer */
342
343                 full_table = ACPI_ALLOCATE(header->length);
344                 if (!full_table) {
345                         ACPI_ERROR((AE_INFO,
346                                     "Could not allocate table memory for [%4.4s] length %X",
347                                     header->signature, header->length));
348                         return_ACPI_STATUS(AE_NO_MEMORY);
349                 }
350
351                 /* Copy the entire table (including header) to the local buffer */
352
353                 ACPI_MEMCPY(full_table, address->pointer.logical,
354                             header->length);
355
356                 /* Save allocation type */
357
358                 allocation = ACPI_MEM_ALLOCATED;
359                 break;
360
361         case ACPI_LOGMODE_PHYSPTR:
362
363                 /*
364                  * Just map the table's physical memory
365                  * into our address space.
366                  */
367                 status = acpi_os_map_memory(address->pointer.physical,
368                                             (acpi_size) header->length,
369                                             ACPI_CAST_PTR(void, &full_table));
370                 if (ACPI_FAILURE(status)) {
371                         ACPI_ERROR((AE_INFO,
372                                     "Could not map memory for table [%4.4s] at %8.8X%8.8X for length %X",
373                                     header->signature,
374                                     ACPI_FORMAT_UINT64(address->pointer.
375                                                        physical),
376                                     header->length));
377                         return (status);
378                 }
379
380                 /* Save allocation type */
381
382                 allocation = ACPI_MEM_MAPPED;
383                 break;
384
385         default:
386
387                 ACPI_ERROR((AE_INFO, "Invalid address flags %X",
388                             address->pointer_type));
389                 return_ACPI_STATUS(AE_BAD_PARAMETER);
390         }
391
392         /*
393          * Validate checksum for _most_ tables,
394          * even the ones whose signature we don't recognize
395          */
396         if (table_info->type != ACPI_TABLE_ID_FACS) {
397                 status = acpi_tb_verify_table_checksum(full_table);
398
399 #if (!ACPI_CHECKSUM_ABORT)
400                 if (ACPI_FAILURE(status)) {
401
402                         /* Ignore the error if configuration says so */
403
404                         status = AE_OK;
405                 }
406 #endif
407         }
408
409         /* Return values */
410
411         table_info->pointer = full_table;
412         table_info->length = (acpi_size) header->length;
413         table_info->allocation = allocation;
414
415         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
416                           "Found table [%4.4s] at %8.8X%8.8X, mapped/copied to %p\n",
417                           full_table->signature,
418                           ACPI_FORMAT_UINT64(address->pointer.physical),
419                           full_table));
420
421         return_ACPI_STATUS(status);
422 }
423
424 /*******************************************************************************
425  *
426  * FUNCTION:    acpi_tb_get_table_ptr
427  *
428  * PARAMETERS:  table_type      - one of the defined table types
429  *              Instance        - Which table of this type
430  *              return_table    - pointer to location to place the pointer for
431  *                                return
432  *
433  * RETURN:      Status
434  *
435  * DESCRIPTION: This function is called to get the pointer to an ACPI table.
436  *
437  ******************************************************************************/
438
439 acpi_status
440 acpi_tb_get_table_ptr(acpi_table_type table_type,
441                       u32 instance, struct acpi_table_header **return_table)
442 {
443         struct acpi_table_desc *table_desc;
444         u32 i;
445
446         ACPI_FUNCTION_TRACE(tb_get_table_ptr);
447
448         if (table_type > ACPI_TABLE_ID_MAX) {
449                 return_ACPI_STATUS(AE_BAD_PARAMETER);
450         }
451
452         /* Check for instance out of range of the current table count */
453
454         if (instance > acpi_gbl_table_lists[table_type].count) {
455                 return_ACPI_STATUS(AE_NOT_EXIST);
456         }
457
458         /*
459          * Walk the list to get the desired table
460          * Note: Instance is one-based
461          */
462         table_desc = acpi_gbl_table_lists[table_type].next;
463         for (i = 1; i < instance; i++) {
464                 table_desc = table_desc->next;
465         }
466
467         /* We are now pointing to the requested table's descriptor */
468
469         *return_table = table_desc->pointer;
470         return_ACPI_STATUS(AE_OK);
471 }