1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 2 /****************************************************************************** 3 * 4 * Module Name: tbutils - ACPI Table utilities 5 * 6 * Copyright (C) 2000 - 2022, Intel Corp. 7 * 8 *****************************************************************************/ 9 10 #include <acpi/acpi.h> 11 #include "accommon.h" 12 #include "actables.h" 13 14 #define _COMPONENT ACPI_TABLES 15 ACPI_MODULE_NAME("tbutils") 16 17 /* Local prototypes */ 18 static acpi_physical_address 19 acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size); 20 21 #if (!ACPI_REDUCED_HARDWARE) 22 /******************************************************************************* 23 * 24 * FUNCTION: acpi_tb_initialize_facs 25 * 26 * PARAMETERS: None 27 * 28 * RETURN: Status 29 * 30 * DESCRIPTION: Create a permanent mapping for the FADT and save it in a global 31 * for accessing the Global Lock and Firmware Waking Vector 32 * 33 ******************************************************************************/ 34 35 acpi_status acpi_tb_initialize_facs(void) 36 { 37 struct acpi_table_facs *facs; 38 39 /* If Hardware Reduced flag is set, there is no FACS */ 40 41 if (acpi_gbl_reduced_hardware) { 42 acpi_gbl_FACS = NULL; 43 return (AE_OK); 44 } else if (acpi_gbl_FADT.Xfacs && 45 (!acpi_gbl_FADT.facs 46 || !acpi_gbl_use32_bit_facs_addresses)) { 47 (void)acpi_get_table_by_index(acpi_gbl_xfacs_index, 48 ACPI_CAST_INDIRECT_PTR(struct 49 acpi_table_header, 50 &facs)); 51 acpi_gbl_FACS = facs; 52 } else if (acpi_gbl_FADT.facs) { 53 (void)acpi_get_table_by_index(acpi_gbl_facs_index, 54 ACPI_CAST_INDIRECT_PTR(struct 55 acpi_table_header, 56 &facs)); 57 acpi_gbl_FACS = facs; 58 } 59 60 /* If there is no FACS, just continue. There was already an error msg */ 61 62 return (AE_OK); 63 } 64 #endif /* !ACPI_REDUCED_HARDWARE */ 65 66 /******************************************************************************* 67 * 68 * FUNCTION: acpi_tb_check_dsdt_header 69 * 70 * PARAMETERS: None 71 * 72 * RETURN: None 73 * 74 * DESCRIPTION: Quick compare to check validity of the DSDT. This will detect 75 * if the DSDT has been replaced from outside the OS and/or if 76 * the DSDT header has been corrupted. 77 * 78 ******************************************************************************/ 79 80 void acpi_tb_check_dsdt_header(void) 81 { 82 83 /* Compare original length and checksum to current values */ 84 85 if (acpi_gbl_original_dsdt_header.length != acpi_gbl_DSDT->length || 86 acpi_gbl_original_dsdt_header.checksum != acpi_gbl_DSDT->checksum) { 87 ACPI_BIOS_ERROR((AE_INFO, 88 "The DSDT has been corrupted or replaced - " 89 "old, new headers below")); 90 91 acpi_tb_print_table_header(0, &acpi_gbl_original_dsdt_header); 92 acpi_tb_print_table_header(0, acpi_gbl_DSDT); 93 94 ACPI_ERROR((AE_INFO, 95 "Please send DMI info to linux-acpi@vger.kernel.org\n" 96 "If system does not work as expected, please boot with acpi=copy_dsdt")); 97 98 /* Disable further error messages */ 99 100 acpi_gbl_original_dsdt_header.length = acpi_gbl_DSDT->length; 101 acpi_gbl_original_dsdt_header.checksum = 102 acpi_gbl_DSDT->checksum; 103 } 104 } 105 106 /******************************************************************************* 107 * 108 * FUNCTION: acpi_tb_copy_dsdt 109 * 110 * PARAMETERS: table_index - Index of installed table to copy 111 * 112 * RETURN: The copied DSDT 113 * 114 * DESCRIPTION: Implements a subsystem option to copy the DSDT to local memory. 115 * Some very bad BIOSs are known to either corrupt the DSDT or 116 * install a new, bad DSDT. This copy works around the problem. 117 * 118 ******************************************************************************/ 119 120 struct acpi_table_header *acpi_tb_copy_dsdt(u32 table_index) 121 { 122 struct acpi_table_header *new_table; 123 struct acpi_table_desc *table_desc; 124 125 table_desc = &acpi_gbl_root_table_list.tables[table_index]; 126 127 new_table = ACPI_ALLOCATE(table_desc->length); 128 if (!new_table) { 129 ACPI_ERROR((AE_INFO, "Could not copy DSDT of length 0x%X", 130 table_desc->length)); 131 return (NULL); 132 } 133 134 memcpy(new_table, table_desc->pointer, table_desc->length); 135 acpi_tb_uninstall_table(table_desc); 136 137 acpi_tb_init_table_descriptor(&acpi_gbl_root_table_list. 138 tables[acpi_gbl_dsdt_index], 139 ACPI_PTR_TO_PHYSADDR(new_table), 140 ACPI_TABLE_ORIGIN_INTERNAL_VIRTUAL, 141 new_table); 142 143 ACPI_INFO(("Forced DSDT copy: length 0x%05X copied locally, original unmapped", new_table->length)); 144 145 return (new_table); 146 } 147 148 /******************************************************************************* 149 * 150 * FUNCTION: acpi_tb_get_root_table_entry 151 * 152 * PARAMETERS: table_entry - Pointer to the RSDT/XSDT table entry 153 * table_entry_size - sizeof 32 or 64 (RSDT or XSDT) 154 * 155 * RETURN: Physical address extracted from the root table 156 * 157 * DESCRIPTION: Get one root table entry. Handles 32-bit and 64-bit cases on 158 * both 32-bit and 64-bit platforms 159 * 160 * NOTE: acpi_physical_address is 32-bit on 32-bit platforms, 64-bit on 161 * 64-bit platforms. 162 * 163 ******************************************************************************/ 164 165 static acpi_physical_address 166 acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size) 167 { 168 u64 address64; 169 170 /* 171 * Get the table physical address (32-bit for RSDT, 64-bit for XSDT): 172 * Note: Addresses are 32-bit aligned (not 64) in both RSDT and XSDT 173 */ 174 if (table_entry_size == ACPI_RSDT_ENTRY_SIZE) { 175 /* 176 * 32-bit platform, RSDT: Return 32-bit table entry 177 * 64-bit platform, RSDT: Expand 32-bit to 64-bit and return 178 */ 179 return ((acpi_physical_address) 180 (*ACPI_CAST_PTR(u32, table_entry))); 181 } else { 182 /* 183 * 32-bit platform, XSDT: Truncate 64-bit to 32-bit and return 184 * 64-bit platform, XSDT: Move (unaligned) 64-bit to local, 185 * return 64-bit 186 */ 187 ACPI_MOVE_64_TO_64(&address64, table_entry); 188 189 #if ACPI_MACHINE_WIDTH == 32 190 if (address64 > ACPI_UINT32_MAX) { 191 192 /* Will truncate 64-bit address to 32 bits, issue warning */ 193 194 ACPI_BIOS_WARNING((AE_INFO, 195 "64-bit Physical Address in XSDT is too large (0x%8.8X%8.8X)," 196 " truncating", 197 ACPI_FORMAT_UINT64(address64))); 198 } 199 #endif 200 return ((acpi_physical_address)(address64)); 201 } 202 } 203 204 /******************************************************************************* 205 * 206 * FUNCTION: acpi_tb_parse_root_table 207 * 208 * PARAMETERS: rsdp_address - Pointer to the RSDP 209 * 210 * RETURN: Status 211 * 212 * DESCRIPTION: This function is called to parse the Root System Description 213 * Table (RSDT or XSDT) 214 * 215 * NOTE: Tables are mapped (not copied) for efficiency. The FACS must 216 * be mapped and cannot be copied because it contains the actual 217 * memory location of the ACPI Global Lock. 218 * 219 ******************************************************************************/ 220 221 acpi_status ACPI_INIT_FUNCTION 222 acpi_tb_parse_root_table(acpi_physical_address rsdp_address) 223 { 224 struct acpi_table_rsdp *rsdp; 225 u32 table_entry_size; 226 u32 i; 227 u32 table_count; 228 struct acpi_table_header *table; 229 acpi_physical_address address; 230 u32 length; 231 u8 *table_entry; 232 acpi_status status; 233 u32 table_index; 234 235 ACPI_FUNCTION_TRACE(tb_parse_root_table); 236 237 /* Map the entire RSDP and extract the address of the RSDT or XSDT */ 238 239 rsdp = acpi_os_map_memory(rsdp_address, sizeof(struct acpi_table_rsdp)); 240 if (!rsdp) { 241 return_ACPI_STATUS(AE_NO_MEMORY); 242 } 243 244 acpi_tb_print_table_header(rsdp_address, 245 ACPI_CAST_PTR(struct acpi_table_header, 246 rsdp)); 247 248 /* Use XSDT if present and not overridden. Otherwise, use RSDT */ 249 250 if ((rsdp->revision > 1) && 251 rsdp->xsdt_physical_address && !acpi_gbl_do_not_use_xsdt) { 252 /* 253 * RSDP contains an XSDT (64-bit physical addresses). We must use 254 * the XSDT if the revision is > 1 and the XSDT pointer is present, 255 * as per the ACPI specification. 256 */ 257 address = (acpi_physical_address)rsdp->xsdt_physical_address; 258 table_entry_size = ACPI_XSDT_ENTRY_SIZE; 259 } else { 260 /* Root table is an RSDT (32-bit physical addresses) */ 261 262 address = (acpi_physical_address)rsdp->rsdt_physical_address; 263 table_entry_size = ACPI_RSDT_ENTRY_SIZE; 264 } 265 266 /* 267 * It is not possible to map more than one entry in some environments, 268 * so unmap the RSDP here before mapping other tables 269 */ 270 acpi_os_unmap_memory(rsdp, sizeof(struct acpi_table_rsdp)); 271 272 /* Map the RSDT/XSDT table header to get the full table length */ 273 274 table = acpi_os_map_memory(address, sizeof(struct acpi_table_header)); 275 if (!table) { 276 return_ACPI_STATUS(AE_NO_MEMORY); 277 } 278 279 acpi_tb_print_table_header(address, table); 280 281 /* 282 * Validate length of the table, and map entire table. 283 * Minimum length table must contain at least one entry. 284 */ 285 length = table->length; 286 acpi_os_unmap_memory(table, sizeof(struct acpi_table_header)); 287 288 if (length < (sizeof(struct acpi_table_header) + table_entry_size)) { 289 ACPI_BIOS_ERROR((AE_INFO, 290 "Invalid table length 0x%X in RSDT/XSDT", 291 length)); 292 return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH); 293 } 294 295 table = acpi_os_map_memory(address, length); 296 if (!table) { 297 return_ACPI_STATUS(AE_NO_MEMORY); 298 } 299 300 /* Validate the root table checksum */ 301 302 status = acpi_ut_verify_checksum(table, length); 303 if (ACPI_FAILURE(status)) { 304 acpi_os_unmap_memory(table, length); 305 return_ACPI_STATUS(status); 306 } 307 308 /* Get the number of entries and pointer to first entry */ 309 310 table_count = (u32)((table->length - sizeof(struct acpi_table_header)) / 311 table_entry_size); 312 table_entry = ACPI_ADD_PTR(u8, table, sizeof(struct acpi_table_header)); 313 314 /* Initialize the root table array from the RSDT/XSDT */ 315 316 for (i = 0; i < table_count; i++) { 317 318 /* Get the table physical address (32-bit for RSDT, 64-bit for XSDT) */ 319 320 address = 321 acpi_tb_get_root_table_entry(table_entry, table_entry_size); 322 323 /* Skip NULL entries in RSDT/XSDT */ 324 325 if (!address) { 326 goto next_table; 327 } 328 329 status = acpi_tb_install_standard_table(address, 330 ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL, 331 NULL, FALSE, TRUE, 332 &table_index); 333 334 if (ACPI_SUCCESS(status) && 335 ACPI_COMPARE_NAMESEG(&acpi_gbl_root_table_list. 336 tables[table_index].signature, 337 ACPI_SIG_FADT)) { 338 acpi_gbl_fadt_index = table_index; 339 acpi_tb_parse_fadt(); 340 } 341 342 next_table: 343 344 table_entry += table_entry_size; 345 } 346 347 acpi_os_unmap_memory(table, length); 348 return_ACPI_STATUS(AE_OK); 349 } 350 351 /******************************************************************************* 352 * 353 * FUNCTION: acpi_tb_get_table 354 * 355 * PARAMETERS: table_desc - Table descriptor 356 * out_table - Where the pointer to the table is returned 357 * 358 * RETURN: Status and pointer to the requested table 359 * 360 * DESCRIPTION: Increase a reference to a table descriptor and return the 361 * validated table pointer. 362 * If the table descriptor is an entry of the root table list, 363 * this API must be invoked with ACPI_MTX_TABLES acquired. 364 * 365 ******************************************************************************/ 366 367 acpi_status 368 acpi_tb_get_table(struct acpi_table_desc *table_desc, 369 struct acpi_table_header **out_table) 370 { 371 acpi_status status; 372 373 ACPI_FUNCTION_TRACE(acpi_tb_get_table); 374 375 if (table_desc->validation_count == 0) { 376 377 /* Table need to be "VALIDATED" */ 378 379 status = acpi_tb_validate_table(table_desc); 380 if (ACPI_FAILURE(status)) { 381 return_ACPI_STATUS(status); 382 } 383 } 384 385 if (table_desc->validation_count < ACPI_MAX_TABLE_VALIDATIONS) { 386 table_desc->validation_count++; 387 388 /* 389 * Detect validation_count overflows to ensure that the warning 390 * message will only be printed once. 391 */ 392 if (table_desc->validation_count >= ACPI_MAX_TABLE_VALIDATIONS) { 393 ACPI_WARNING((AE_INFO, 394 "Table %p, Validation count overflows\n", 395 table_desc)); 396 } 397 } 398 399 *out_table = table_desc->pointer; 400 return_ACPI_STATUS(AE_OK); 401 } 402 403 /******************************************************************************* 404 * 405 * FUNCTION: acpi_tb_put_table 406 * 407 * PARAMETERS: table_desc - Table descriptor 408 * 409 * RETURN: None 410 * 411 * DESCRIPTION: Decrease a reference to a table descriptor and release the 412 * validated table pointer if no references. 413 * If the table descriptor is an entry of the root table list, 414 * this API must be invoked with ACPI_MTX_TABLES acquired. 415 * 416 ******************************************************************************/ 417 418 void acpi_tb_put_table(struct acpi_table_desc *table_desc) 419 { 420 421 ACPI_FUNCTION_TRACE(acpi_tb_put_table); 422 423 if (table_desc->validation_count < ACPI_MAX_TABLE_VALIDATIONS) { 424 table_desc->validation_count--; 425 426 /* 427 * Detect validation_count underflows to ensure that the warning 428 * message will only be printed once. 429 */ 430 if (table_desc->validation_count >= ACPI_MAX_TABLE_VALIDATIONS) { 431 ACPI_WARNING((AE_INFO, 432 "Table %p, Validation count underflows\n", 433 table_desc)); 434 return_VOID; 435 } 436 } 437 438 if (table_desc->validation_count == 0) { 439 440 /* Table need to be "INVALIDATED" */ 441 442 acpi_tb_invalidate_table(table_desc); 443 } 444 445 return_VOID; 446 } 447