acpi/acpica/tbutils.c

0001 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
0002 /******************************************************************************
0003  *
0004  * Module Name: tbutils - ACPI Table utilities
0005  *
0006  * Copyright (C) 2000 - 2022, Intel Corp.
0007  *
0008  *****************************************************************************/
0009
0010 #include <acpi/acpi.h>
0011 #include "accommon.h"
0012 #include "actables.h"
0013
0014 #define _COMPONENT          ACPI_TABLES
0015 ACPI_MODULE_NAME("tbutils")
0016
0017 /* Local prototypes */
0018 static acpi_physical_address
0019 acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size);
0020
0021 #if (!ACPI_REDUCED_HARDWARE)
0022 /*******************************************************************************
0023  *
0024  * FUNCTION:    acpi_tb_initialize_facs
0025  *
0026  * PARAMETERS:  None
0027  *
0028  * RETURN:      Status
0029  *
0030  * DESCRIPTION: Create a permanent mapping for the FADT and save it in a global
0031  *              for accessing the Global Lock and Firmware Waking Vector
0032  *
0033  ******************************************************************************/
0034
0035 acpi_status acpi_tb_initialize_facs(void)
0036 {
0037     struct acpi_table_facs *facs;
0038
0039     /* If Hardware Reduced flag is set, there is no FACS */
0040
0041     if (acpi_gbl_reduced_hardware) {
0042         acpi_gbl_FACS = NULL;
0043         return (AE_OK);
0044     } else if (acpi_gbl_FADT.Xfacs &&
0045            (!acpi_gbl_FADT.facs
0046             || !acpi_gbl_use32_bit_facs_addresses)) {
0047         (void)acpi_get_table_by_index(acpi_gbl_xfacs_index,
0048                           ACPI_CAST_INDIRECT_PTR(struct
0049                                      acpi_table_header,
0050                                      &facs));
0051         acpi_gbl_FACS = facs;
0052     } else if (acpi_gbl_FADT.facs) {
0053         (void)acpi_get_table_by_index(acpi_gbl_facs_index,
0054                           ACPI_CAST_INDIRECT_PTR(struct
0055                                      acpi_table_header,
0056                                      &facs));
0057         acpi_gbl_FACS = facs;
0058     }
0059
0060     /* If there is no FACS, just continue. There was already an error msg */
0061
0062     return (AE_OK);
0063 }
0064 #endif              /* !ACPI_REDUCED_HARDWARE */
0065
0066 /*******************************************************************************
0067  *
0068  * FUNCTION:    acpi_tb_check_dsdt_header
0069  *
0070  * PARAMETERS:  None
0071  *
0072  * RETURN:      None
0073  *
0074  * DESCRIPTION: Quick compare to check validity of the DSDT. This will detect
0075  *              if the DSDT has been replaced from outside the OS and/or if
0076  *              the DSDT header has been corrupted.
0077  *
0078  ******************************************************************************/
0079
0080 void acpi_tb_check_dsdt_header(void)
0081 {
0082
0083     /* Compare original length and checksum to current values */
0084
0085     if (acpi_gbl_original_dsdt_header.length != acpi_gbl_DSDT->length ||
0086         acpi_gbl_original_dsdt_header.checksum != acpi_gbl_DSDT->checksum) {
0087         ACPI_BIOS_ERROR((AE_INFO,
0088                  "The DSDT has been corrupted or replaced - "
0089                  "old, new headers below"));
0090
0091         acpi_tb_print_table_header(0, &acpi_gbl_original_dsdt_header);
0092         acpi_tb_print_table_header(0, acpi_gbl_DSDT);
0093
0094         ACPI_ERROR((AE_INFO,
0095                 "Please send DMI info to linux-acpi@vger.kernel.org\n"
0096                 "If system does not work as expected, please boot with acpi=copy_dsdt"));
0097
0098         /* Disable further error messages */
0099
0100         acpi_gbl_original_dsdt_header.length = acpi_gbl_DSDT->length;
0101         acpi_gbl_original_dsdt_header.checksum =
0102             acpi_gbl_DSDT->checksum;
0103     }
0104 }
0105
0106 /*******************************************************************************
0107  *
0108  * FUNCTION:    acpi_tb_copy_dsdt
0109  *
0110  * PARAMETERS:  table_index         - Index of installed table to copy
0111  *
0112  * RETURN:      The copied DSDT
0113  *
0114  * DESCRIPTION: Implements a subsystem option to copy the DSDT to local memory.
0115  *              Some very bad BIOSs are known to either corrupt the DSDT or
0116  *              install a new, bad DSDT. This copy works around the problem.
0117  *
0118  ******************************************************************************/
0119
0120 struct acpi_table_header *acpi_tb_copy_dsdt(u32 table_index)
0121 {
0122     struct acpi_table_header *new_table;
0123     struct acpi_table_desc *table_desc;
0124
0125     table_desc = &acpi_gbl_root_table_list.tables[table_index];
0126
0127     new_table = ACPI_ALLOCATE(table_desc->length);
0128     if (!new_table) {
0129         ACPI_ERROR((AE_INFO, "Could not copy DSDT of length 0x%X",
0130                 table_desc->length));
0131         return (NULL);
0132     }
0133
0134     memcpy(new_table, table_desc->pointer, table_desc->length);
0135     acpi_tb_uninstall_table(table_desc);
0136
0137     acpi_tb_init_table_descriptor(&acpi_gbl_root_table_list.
0138                       tables[acpi_gbl_dsdt_index],
0139                       ACPI_PTR_TO_PHYSADDR(new_table),
0140                       ACPI_TABLE_ORIGIN_INTERNAL_VIRTUAL,
0141                       new_table);
0142
0143     ACPI_INFO(("Forced DSDT copy: length 0x%05X copied locally, original unmapped", new_table->length));
0144
0145     return (new_table);
0146 }
0147
0148 /*******************************************************************************
0149  *
0150  * FUNCTION:    acpi_tb_get_root_table_entry
0151  *
0152  * PARAMETERS:  table_entry         - Pointer to the RSDT/XSDT table entry
0153  *              table_entry_size    - sizeof 32 or 64 (RSDT or XSDT)
0154  *
0155  * RETURN:      Physical address extracted from the root table
0156  *
0157  * DESCRIPTION: Get one root table entry. Handles 32-bit and 64-bit cases on
0158  *              both 32-bit and 64-bit platforms
0159  *
0160  * NOTE:        acpi_physical_address is 32-bit on 32-bit platforms, 64-bit on
0161  *              64-bit platforms.
0162  *
0163  ******************************************************************************/
0164
0165 static acpi_physical_address
0166 acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size)
0167 {
0168     u64 address64;
0169
0170     /*
0171      * Get the table physical address (32-bit for RSDT, 64-bit for XSDT):
0172      * Note: Addresses are 32-bit aligned (not 64) in both RSDT and XSDT
0173      */
0174     if (table_entry_size == ACPI_RSDT_ENTRY_SIZE) {
0175         /*
0176          * 32-bit platform, RSDT: Return 32-bit table entry
0177          * 64-bit platform, RSDT: Expand 32-bit to 64-bit and return
0178          */
0179         return ((acpi_physical_address)
0180             (*ACPI_CAST_PTR(u32, table_entry)));
0181     } else {
0182         /*
0183          * 32-bit platform, XSDT: Truncate 64-bit to 32-bit and return
0184          * 64-bit platform, XSDT: Move (unaligned) 64-bit to local,
0185          *  return 64-bit
0186          */
0187         ACPI_MOVE_64_TO_64(&address64, table_entry);
0188
0189 #if ACPI_MACHINE_WIDTH == 32
0190         if (address64 > ACPI_UINT32_MAX) {
0191
0192             /* Will truncate 64-bit address to 32 bits, issue warning */
0193
0194             ACPI_BIOS_WARNING((AE_INFO,
0195                        "64-bit Physical Address in XSDT is too large (0x%8.8X%8.8X),"
0196                        " truncating",
0197                        ACPI_FORMAT_UINT64(address64)));
0198         }
0199 #endif
0200         return ((acpi_physical_address)(address64));
0201     }
0202 }
0203
0204 /*******************************************************************************
0205  *
0206  * FUNCTION:    acpi_tb_parse_root_table
0207  *
0208  * PARAMETERS:  rsdp_address        - Pointer to the RSDP
0209  *
0210  * RETURN:      Status
0211  *
0212  * DESCRIPTION: This function is called to parse the Root System Description
0213  *              Table (RSDT or XSDT)
0214  *
0215  * NOTE:        Tables are mapped (not copied) for efficiency. The FACS must
0216  *              be mapped and cannot be copied because it contains the actual
0217  *              memory location of the ACPI Global Lock.
0218  *
0219  ******************************************************************************/
0220
0221 acpi_status ACPI_INIT_FUNCTION
0222 acpi_tb_parse_root_table(acpi_physical_address rsdp_address)
0223 {
0224     struct acpi_table_rsdp *rsdp;
0225     u32 table_entry_size;
0226     u32 i;
0227     u32 table_count;
0228     struct acpi_table_header *table;
0229     acpi_physical_address address;
0230     u32 length;
0231     u8 *table_entry;
0232     acpi_status status;
0233     u32 table_index;
0234
0235     ACPI_FUNCTION_TRACE(tb_parse_root_table);
0236
0237     /* Map the entire RSDP and extract the address of the RSDT or XSDT */
0238
0239     rsdp = acpi_os_map_memory(rsdp_address, sizeof(struct acpi_table_rsdp));
0240     if (!rsdp) {
0241         return_ACPI_STATUS(AE_NO_MEMORY);
0242     }
0243
0244     acpi_tb_print_table_header(rsdp_address,
0245                    ACPI_CAST_PTR(struct acpi_table_header,
0246                          rsdp));
0247
0248     /* Use XSDT if present and not overridden. Otherwise, use RSDT */
0249
0250     if ((rsdp->revision > 1) &&
0251         rsdp->xsdt_physical_address && !acpi_gbl_do_not_use_xsdt) {
0252         /*
0253          * RSDP contains an XSDT (64-bit physical addresses). We must use
0254          * the XSDT if the revision is > 1 and the XSDT pointer is present,
0255          * as per the ACPI specification.
0256          */
0257         address = (acpi_physical_address)rsdp->xsdt_physical_address;
0258         table_entry_size = ACPI_XSDT_ENTRY_SIZE;
0259     } else {
0260         /* Root table is an RSDT (32-bit physical addresses) */
0261
0262         address = (acpi_physical_address)rsdp->rsdt_physical_address;
0263         table_entry_size = ACPI_RSDT_ENTRY_SIZE;
0264     }
0265
0266     /*
0267      * It is not possible to map more than one entry in some environments,
0268      * so unmap the RSDP here before mapping other tables
0269      */
0270     acpi_os_unmap_memory(rsdp, sizeof(struct acpi_table_rsdp));
0271
0272     /* Map the RSDT/XSDT table header to get the full table length */
0273
0274     table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
0275     if (!table) {
0276         return_ACPI_STATUS(AE_NO_MEMORY);
0277     }
0278
0279     acpi_tb_print_table_header(address, table);
0280
0281     /*
0282      * Validate length of the table, and map entire table.
0283      * Minimum length table must contain at least one entry.
0284      */
0285     length = table->length;
0286     acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
0287
0288     if (length < (sizeof(struct acpi_table_header) + table_entry_size)) {
0289         ACPI_BIOS_ERROR((AE_INFO,
0290                  "Invalid table length 0x%X in RSDT/XSDT",
0291                  length));
0292         return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
0293     }
0294
0295     table = acpi_os_map_memory(address, length);
0296     if (!table) {
0297         return_ACPI_STATUS(AE_NO_MEMORY);
0298     }
0299
0300     /* Validate the root table checksum */
0301
0302     status = acpi_tb_verify_checksum(table, length);
0303     if (ACPI_FAILURE(status)) {
0304         acpi_os_unmap_memory(table, length);
0305         return_ACPI_STATUS(status);
0306     }
0307
0308     /* Get the number of entries and pointer to first entry */
0309
0310     table_count = (u32)((table->length - sizeof(struct acpi_table_header)) /
0311                 table_entry_size);
0312     table_entry = ACPI_ADD_PTR(u8, table, sizeof(struct acpi_table_header));
0313
0314     /* Initialize the root table array from the RSDT/XSDT */
0315
0316     for (i = 0; i < table_count; i++) {
0317
0318         /* Get the table physical address (32-bit for RSDT, 64-bit for XSDT) */
0319
0320         address =
0321             acpi_tb_get_root_table_entry(table_entry, table_entry_size);
0322
0323         /* Skip NULL entries in RSDT/XSDT */
0324
0325         if (!address) {
0326             goto next_table;
0327         }
0328
0329         status = acpi_tb_install_standard_table(address,
0330                             ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL,
0331                             NULL, FALSE, TRUE,
0332                             &table_index);
0333
0334         if (ACPI_SUCCESS(status) &&
0335             ACPI_COMPARE_NAMESEG(&acpi_gbl_root_table_list.
0336                      tables[table_index].signature,
0337                      ACPI_SIG_FADT)) {
0338             acpi_gbl_fadt_index = table_index;
0339             acpi_tb_parse_fadt();
0340         }
0341
0342 next_table:
0343
0344         table_entry += table_entry_size;
0345     }
0346
0347     acpi_os_unmap_memory(table, length);
0348     return_ACPI_STATUS(AE_OK);
0349 }
0350
0351 /*******************************************************************************
0352  *
0353  * FUNCTION:    acpi_tb_get_table
0354  *
0355  * PARAMETERS:  table_desc          - Table descriptor
0356  *              out_table           - Where the pointer to the table is returned
0357  *
0358  * RETURN:      Status and pointer to the requested table
0359  *
0360  * DESCRIPTION: Increase a reference to a table descriptor and return the
0361  *              validated table pointer.
0362  *              If the table descriptor is an entry of the root table list,
0363  *              this API must be invoked with ACPI_MTX_TABLES acquired.
0364  *
0365  ******************************************************************************/
0366
0367 acpi_status
0368 acpi_tb_get_table(struct acpi_table_desc *table_desc,
0369           struct acpi_table_header **out_table)
0370 {
0371     acpi_status status;
0372
0373     ACPI_FUNCTION_TRACE(acpi_tb_get_table);
0374
0375     if (table_desc->validation_count == 0) {
0376
0377         /* Table need to be "VALIDATED" */
0378
0379         status = acpi_tb_validate_table(table_desc);
0380         if (ACPI_FAILURE(status)) {
0381             return_ACPI_STATUS(status);
0382         }
0383     }
0384
0385     if (table_desc->validation_count < ACPI_MAX_TABLE_VALIDATIONS) {
0386         table_desc->validation_count++;
0387
0388         /*
0389          * Detect validation_count overflows to ensure that the warning
0390          * message will only be printed once.
0391          */
0392         if (table_desc->validation_count >= ACPI_MAX_TABLE_VALIDATIONS) {
0393             ACPI_WARNING((AE_INFO,
0394                       "Table %p, Validation count overflows\n",
0395                       table_desc));
0396         }
0397     }
0398
0399     *out_table = table_desc->pointer;
0400     return_ACPI_STATUS(AE_OK);
0401 }
0402
0403 /*******************************************************************************
0404  *
0405  * FUNCTION:    acpi_tb_put_table
0406  *
0407  * PARAMETERS:  table_desc          - Table descriptor
0408  *
0409  * RETURN:      None
0410  *
0411  * DESCRIPTION: Decrease a reference to a table descriptor and release the
0412  *              validated table pointer if no references.
0413  *              If the table descriptor is an entry of the root table list,
0414  *              this API must be invoked with ACPI_MTX_TABLES acquired.
0415  *
0416  ******************************************************************************/
0417
0418 void acpi_tb_put_table(struct acpi_table_desc *table_desc)
0419 {
0420
0421     ACPI_FUNCTION_TRACE(acpi_tb_put_table);
0422
0423     if (table_desc->validation_count < ACPI_MAX_TABLE_VALIDATIONS) {
0424         table_desc->validation_count--;
0425
0426         /*
0427          * Detect validation_count underflows to ensure that the warning
0428          * message will only be printed once.
0429          */
0430         if (table_desc->validation_count >= ACPI_MAX_TABLE_VALIDATIONS) {
0431             ACPI_WARNING((AE_INFO,
0432                       "Table %p, Validation count underflows\n",
0433                       table_desc));
0434             return_VOID;
0435         }
0436     }
0437
0438     if (table_desc->validation_count == 0) {
0439
0440         /* Table need to be "INVALIDATED" */
0441
0442         acpi_tb_invalidate_table(table_desc);
0443     }
0444
0445     return_VOID;
0446 }