Committer: Michael Beasley <mike@snafu.setup>
[mikesnafu-overlay.git] / drivers / acpi / tables / tbutils.c
blob010f19652f80a633305a9da6c73729a73f58f545
1 /******************************************************************************
3 * Module Name: tbutils - table utilities
5 *****************************************************************************/
7 /*
8 * Copyright (C) 2000 - 2007, R. Byron Moore
9 * All rights reserved.
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.
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.
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.
44 #include <acpi/acpi.h>
45 #include <acpi/actables.h>
47 #define _COMPONENT ACPI_TABLES
48 ACPI_MODULE_NAME("tbutils")
50 /* Local prototypes */
51 static acpi_physical_address
52 acpi_tb_get_root_table_entry(u8 * table_entry,
53 acpi_native_uint table_entry_size);
54 /*******************************************************************************
56 * FUNCTION: acpi_tb_check_xsdt
58 * PARAMETERS: address - Pointer to the XSDT
60 * RETURN: status
61 * AE_OK - XSDT is okay
62 * AE_NO_MEMORY - can't map XSDT
63 * AE_INVALID_TABLE_LENGTH - invalid table length
64 * AE_NULL_ENTRY - XSDT has NULL entry
66 * DESCRIPTION: validate XSDT
67 ******************************************************************************/
69 static acpi_status
70 acpi_tb_check_xsdt(acpi_physical_address address)
72 struct acpi_table_header *table;
73 u32 length;
74 u64 xsdt_entry_address;
75 u8 *table_entry;
76 u32 table_count;
77 int i;
79 table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
80 if (!table)
81 return AE_NO_MEMORY;
83 length = table->length;
84 acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
85 if (length < sizeof(struct acpi_table_header))
86 return AE_INVALID_TABLE_LENGTH;
88 table = acpi_os_map_memory(address, length);
89 if (!table)
90 return AE_NO_MEMORY;
92 /* Calculate the number of tables described in XSDT */
93 table_count =
94 (u32) ((table->length -
95 sizeof(struct acpi_table_header)) / sizeof(u64));
96 table_entry =
97 ACPI_CAST_PTR(u8, table) + sizeof(struct acpi_table_header);
98 for (i = 0; i < table_count; i++) {
99 ACPI_MOVE_64_TO_64(&xsdt_entry_address, table_entry);
100 if (!xsdt_entry_address) {
101 /* XSDT has NULL entry */
102 break;
104 table_entry += sizeof(u64);
106 acpi_os_unmap_memory(table, length);
108 if (i < table_count)
109 return AE_NULL_ENTRY;
110 else
111 return AE_OK;
114 /*******************************************************************************
116 * FUNCTION: acpi_tb_tables_loaded
118 * PARAMETERS: None
120 * RETURN: TRUE if required ACPI tables are loaded
122 * DESCRIPTION: Determine if the minimum required ACPI tables are present
123 * (FADT, FACS, DSDT)
125 ******************************************************************************/
127 u8 acpi_tb_tables_loaded(void)
130 if (acpi_gbl_root_table_list.count >= 3) {
131 return (TRUE);
134 return (FALSE);
137 /*******************************************************************************
139 * FUNCTION: acpi_tb_print_table_header
141 * PARAMETERS: Address - Table physical address
142 * Header - Table header
144 * RETURN: None
146 * DESCRIPTION: Print an ACPI table header. Special cases for FACS and RSDP.
148 ******************************************************************************/
150 void
151 acpi_tb_print_table_header(acpi_physical_address address,
152 struct acpi_table_header *header)
155 if (ACPI_COMPARE_NAME(header->signature, ACPI_SIG_FACS)) {
157 /* FACS only has signature and length fields of common table header */
159 ACPI_INFO((AE_INFO, "%4.4s %08lX, %04X",
160 header->signature, (unsigned long)address,
161 header->length));
162 } else if (ACPI_COMPARE_NAME(header->signature, ACPI_SIG_RSDP)) {
164 /* RSDP has no common fields */
166 ACPI_INFO((AE_INFO, "RSDP %08lX, %04X (r%d %6.6s)",
167 (unsigned long)address,
168 (ACPI_CAST_PTR(struct acpi_table_rsdp, header)->
169 revision >
170 0) ? ACPI_CAST_PTR(struct acpi_table_rsdp,
171 header)->length : 20,
172 ACPI_CAST_PTR(struct acpi_table_rsdp,
173 header)->revision,
174 ACPI_CAST_PTR(struct acpi_table_rsdp,
175 header)->oem_id));
176 } else {
177 /* Standard ACPI table with full common header */
179 ACPI_INFO((AE_INFO,
180 "%4.4s %08lX, %04X (r%d %6.6s %8.8s %8X %4.4s %8X)",
181 header->signature, (unsigned long)address,
182 header->length, header->revision, header->oem_id,
183 header->oem_table_id, header->oem_revision,
184 header->asl_compiler_id,
185 header->asl_compiler_revision));
189 /*******************************************************************************
191 * FUNCTION: acpi_tb_validate_checksum
193 * PARAMETERS: Table - ACPI table to verify
194 * Length - Length of entire table
196 * RETURN: Status
198 * DESCRIPTION: Verifies that the table checksums to zero. Optionally returns
199 * exception on bad checksum.
201 ******************************************************************************/
203 acpi_status acpi_tb_verify_checksum(struct acpi_table_header *table, u32 length)
205 u8 checksum;
207 /* Compute the checksum on the table */
209 checksum = acpi_tb_checksum(ACPI_CAST_PTR(u8, table), length);
211 /* Checksum ok? (should be zero) */
213 if (checksum) {
214 ACPI_WARNING((AE_INFO,
215 "Incorrect checksum in table [%4.4s] - %2.2X, should be %2.2X",
216 table->signature, table->checksum,
217 (u8) (table->checksum - checksum)));
219 #if (ACPI_CHECKSUM_ABORT)
221 return (AE_BAD_CHECKSUM);
222 #endif
225 return (AE_OK);
228 /*******************************************************************************
230 * FUNCTION: acpi_tb_checksum
232 * PARAMETERS: Buffer - Pointer to memory region to be checked
233 * Length - Length of this memory region
235 * RETURN: Checksum (u8)
237 * DESCRIPTION: Calculates circular checksum of memory region.
239 ******************************************************************************/
241 u8 acpi_tb_checksum(u8 * buffer, acpi_native_uint length)
243 u8 sum = 0;
244 u8 *end = buffer + length;
246 while (buffer < end) {
247 sum = (u8) (sum + *(buffer++));
250 return sum;
253 /*******************************************************************************
255 * FUNCTION: acpi_tb_install_table
257 * PARAMETERS: Address - Physical address of DSDT or FACS
258 * Flags - Flags
259 * Signature - Table signature, NULL if no need to
260 * match
261 * table_index - Index into root table array
263 * RETURN: None
265 * DESCRIPTION: Install an ACPI table into the global data structure.
267 ******************************************************************************/
269 void
270 acpi_tb_install_table(acpi_physical_address address,
271 u8 flags, char *signature, acpi_native_uint table_index)
273 struct acpi_table_header *table;
275 if (!address) {
276 ACPI_ERROR((AE_INFO,
277 "Null physical address for ACPI table [%s]",
278 signature));
279 return;
282 /* Map just the table header */
284 table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
285 if (!table) {
286 return;
289 /* If a particular signature is expected, signature must match */
291 if (signature && !ACPI_COMPARE_NAME(table->signature, signature)) {
292 ACPI_ERROR((AE_INFO,
293 "Invalid signature 0x%X for ACPI table [%s]",
294 *ACPI_CAST_PTR(u32, table->signature), signature));
295 goto unmap_and_exit;
298 /* Initialize the table entry */
300 acpi_gbl_root_table_list.tables[table_index].address = address;
301 acpi_gbl_root_table_list.tables[table_index].length = table->length;
302 acpi_gbl_root_table_list.tables[table_index].flags = flags;
304 ACPI_MOVE_32_TO_32(&
305 (acpi_gbl_root_table_list.tables[table_index].
306 signature), table->signature);
308 acpi_tb_print_table_header(address, table);
310 if (table_index == ACPI_TABLE_INDEX_DSDT) {
312 /* Global integer width is based upon revision of the DSDT */
314 acpi_ut_set_integer_width(table->revision);
317 unmap_and_exit:
318 acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
321 /*******************************************************************************
323 * FUNCTION: acpi_tb_get_root_table_entry
325 * PARAMETERS: table_entry - Pointer to the RSDT/XSDT table entry
326 * table_entry_size - sizeof 32 or 64 (RSDT or XSDT)
328 * RETURN: Physical address extracted from the root table
330 * DESCRIPTION: Get one root table entry. Handles 32-bit and 64-bit cases on
331 * both 32-bit and 64-bit platforms
333 * NOTE: acpi_physical_address is 32-bit on 32-bit platforms, 64-bit on
334 * 64-bit platforms.
336 ******************************************************************************/
338 static acpi_physical_address
339 acpi_tb_get_root_table_entry(u8 * table_entry,
340 acpi_native_uint table_entry_size)
342 u64 address64;
345 * Get the table physical address (32-bit for RSDT, 64-bit for XSDT):
346 * Note: Addresses are 32-bit aligned (not 64) in both RSDT and XSDT
348 if (table_entry_size == sizeof(u32)) {
350 * 32-bit platform, RSDT: Return 32-bit table entry
351 * 64-bit platform, RSDT: Expand 32-bit to 64-bit and return
353 return ((acpi_physical_address)
354 (*ACPI_CAST_PTR(u32, table_entry)));
355 } else {
357 * 32-bit platform, XSDT: Truncate 64-bit to 32-bit and return
358 * 64-bit platform, XSDT: Move (unaligned) 64-bit to local, return 64-bit
360 ACPI_MOVE_64_TO_64(&address64, table_entry);
362 #if ACPI_MACHINE_WIDTH == 32
363 if (address64 > ACPI_UINT32_MAX) {
365 /* Will truncate 64-bit address to 32 bits, issue warning */
367 ACPI_WARNING((AE_INFO,
368 "64-bit Physical Address in XSDT is too large (%8.8X%8.8X), truncating",
369 ACPI_FORMAT_UINT64(address64)));
371 #endif
372 return ((acpi_physical_address) (address64));
376 /*******************************************************************************
378 * FUNCTION: acpi_tb_parse_root_table
380 * PARAMETERS: Rsdp - Pointer to the RSDP
381 * Flags - Flags
383 * RETURN: Status
385 * DESCRIPTION: This function is called to parse the Root System Description
386 * Table (RSDT or XSDT)
388 * NOTE: Tables are mapped (not copied) for efficiency. The FACS must
389 * be mapped and cannot be copied because it contains the actual
390 * memory location of the ACPI Global Lock.
392 ******************************************************************************/
394 acpi_status __init
395 acpi_tb_parse_root_table(acpi_physical_address rsdp_address, u8 flags)
397 struct acpi_table_rsdp *rsdp;
398 acpi_native_uint table_entry_size;
399 acpi_native_uint i;
400 u32 table_count;
401 struct acpi_table_header *table;
402 acpi_physical_address address;
403 acpi_physical_address uninitialized_var(rsdt_address);
404 u32 length;
405 u8 *table_entry;
406 acpi_status status;
408 ACPI_FUNCTION_TRACE(tb_parse_root_table);
411 * Map the entire RSDP and extract the address of the RSDT or XSDT
413 rsdp = acpi_os_map_memory(rsdp_address, sizeof(struct acpi_table_rsdp));
414 if (!rsdp) {
415 return_ACPI_STATUS(AE_NO_MEMORY);
418 acpi_tb_print_table_header(rsdp_address,
419 ACPI_CAST_PTR(struct acpi_table_header,
420 rsdp));
422 /* Differentiate between RSDT and XSDT root tables */
424 if (rsdp->revision > 1 && rsdp->xsdt_physical_address) {
426 * Root table is an XSDT (64-bit physical addresses). We must use the
427 * XSDT if the revision is > 1 and the XSDT pointer is present, as per
428 * the ACPI specification.
430 address = (acpi_physical_address) rsdp->xsdt_physical_address;
431 table_entry_size = sizeof(u64);
432 rsdt_address = (acpi_physical_address)
433 rsdp->rsdt_physical_address;
434 } else {
435 /* Root table is an RSDT (32-bit physical addresses) */
437 address = (acpi_physical_address) rsdp->rsdt_physical_address;
438 table_entry_size = sizeof(u32);
442 * It is not possible to map more than one entry in some environments,
443 * so unmap the RSDP here before mapping other tables
445 acpi_os_unmap_memory(rsdp, sizeof(struct acpi_table_rsdp));
447 if (table_entry_size == sizeof(u64)) {
448 if (acpi_tb_check_xsdt(address) == AE_NULL_ENTRY) {
449 /* XSDT has NULL entry, RSDT is used */
450 address = rsdt_address;
451 table_entry_size = sizeof(u32);
452 ACPI_WARNING((AE_INFO, "BIOS XSDT has NULL entry, "
453 "using RSDT"));
456 /* Map the RSDT/XSDT table header to get the full table length */
458 table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
459 if (!table) {
460 return_ACPI_STATUS(AE_NO_MEMORY);
463 acpi_tb_print_table_header(address, table);
465 /* Get the length of the full table, verify length and map entire table */
467 length = table->length;
468 acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
470 if (length < sizeof(struct acpi_table_header)) {
471 ACPI_ERROR((AE_INFO, "Invalid length 0x%X in RSDT/XSDT",
472 length));
473 return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
476 table = acpi_os_map_memory(address, length);
477 if (!table) {
478 return_ACPI_STATUS(AE_NO_MEMORY);
481 /* Validate the root table checksum */
483 status = acpi_tb_verify_checksum(table, length);
484 if (ACPI_FAILURE(status)) {
485 acpi_os_unmap_memory(table, length);
486 return_ACPI_STATUS(status);
489 /* Calculate the number of tables described in the root table */
491 table_count =
492 (u32) ((table->length -
493 sizeof(struct acpi_table_header)) / table_entry_size);
496 * First two entries in the table array are reserved for the DSDT and FACS,
497 * which are not actually present in the RSDT/XSDT - they come from the FADT
499 table_entry =
500 ACPI_CAST_PTR(u8, table) + sizeof(struct acpi_table_header);
501 acpi_gbl_root_table_list.count = 2;
504 * Initialize the root table array from the RSDT/XSDT
506 for (i = 0; i < table_count; i++) {
507 if (acpi_gbl_root_table_list.count >=
508 acpi_gbl_root_table_list.size) {
510 /* There is no more room in the root table array, attempt resize */
512 status = acpi_tb_resize_root_table_list();
513 if (ACPI_FAILURE(status)) {
514 ACPI_WARNING((AE_INFO,
515 "Truncating %u table entries!",
516 (unsigned)
517 (acpi_gbl_root_table_list.size -
518 acpi_gbl_root_table_list.
519 count)));
520 break;
524 /* Get the table physical address (32-bit for RSDT, 64-bit for XSDT) */
526 acpi_gbl_root_table_list.tables[acpi_gbl_root_table_list.count].
527 address =
528 acpi_tb_get_root_table_entry(table_entry, table_entry_size);
530 table_entry += table_entry_size;
531 acpi_gbl_root_table_list.count++;
535 * It is not possible to map more than one entry in some environments,
536 * so unmap the root table here before mapping other tables
538 acpi_os_unmap_memory(table, length);
541 * Complete the initialization of the root table array by examining
542 * the header of each table
544 for (i = 2; i < acpi_gbl_root_table_list.count; i++) {
545 acpi_tb_install_table(acpi_gbl_root_table_list.tables[i].
546 address, flags, NULL, i);
548 /* Special case for FADT - get the DSDT and FACS */
550 if (ACPI_COMPARE_NAME
551 (&acpi_gbl_root_table_list.tables[i].signature,
552 ACPI_SIG_FADT)) {
553 acpi_tb_parse_fadt(i, flags);
557 return_ACPI_STATUS(AE_OK);