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tbfadt.c
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linux-6.19.14/drivers/acpi/acpica/tbfadt.c
1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 2/****************************************************************************** 3 * 4 * Module Name: tbfadt - FADT table utilities 5 * 6 * Copyright (C) 2000 - 2025, Intel Corp. 7 * 8 *****************************************************************************/ 9 10#include <acpi/acpi.h> 11#include "accommon.h" 12#include "actables.h" 13 14#define _COMPONENT ACPI_TABLES 15ACPI_MODULE_NAME("tbfadt") 16 17/* Local prototypes */ 18static void 19acpi_tb_init_generic_address(struct acpi_generic_address *generic_address, 20 u8 space_id, 21 u8 byte_width, 22 u64 address, const char *register_name, u8 flags); 23 24static void acpi_tb_convert_fadt(void); 25 26static void acpi_tb_setup_fadt_registers(void); 27 28static u64 29acpi_tb_select_address(char *register_name, u32 address32, u64 address64); 30 31/* Table for conversion of FADT to common internal format and FADT validation */ 32 33typedef struct acpi_fadt_info { 34 const char *name; 35 u16 address64; 36 u16 address32; 37 u16 length; 38 u8 default_length; 39 u8 flags; 40 41} acpi_fadt_info; 42 43#define ACPI_FADT_OPTIONAL 0 44#define ACPI_FADT_REQUIRED 1 45#define ACPI_FADT_SEPARATE_LENGTH 2 46#define ACPI_FADT_GPE_REGISTER 4 47 48static struct acpi_fadt_info fadt_info_table[] = { 49 {"Pm1aEventBlock", 50 ACPI_FADT_OFFSET(xpm1a_event_block), 51 ACPI_FADT_OFFSET(pm1a_event_block), 52 ACPI_FADT_OFFSET(pm1_event_length), 53 ACPI_PM1_REGISTER_WIDTH * 2, /* Enable + Status register */ 54 ACPI_FADT_REQUIRED}, 55 56 {"Pm1bEventBlock", 57 ACPI_FADT_OFFSET(xpm1b_event_block), 58 ACPI_FADT_OFFSET(pm1b_event_block), 59 ACPI_FADT_OFFSET(pm1_event_length), 60 ACPI_PM1_REGISTER_WIDTH * 2, /* Enable + Status register */ 61 ACPI_FADT_OPTIONAL}, 62 63 {"Pm1aControlBlock", 64 ACPI_FADT_OFFSET(xpm1a_control_block), 65 ACPI_FADT_OFFSET(pm1a_control_block), 66 ACPI_FADT_OFFSET(pm1_control_length), 67 ACPI_PM1_REGISTER_WIDTH, 68 ACPI_FADT_REQUIRED}, 69 70 {"Pm1bControlBlock", 71 ACPI_FADT_OFFSET(xpm1b_control_block), 72 ACPI_FADT_OFFSET(pm1b_control_block), 73 ACPI_FADT_OFFSET(pm1_control_length), 74 ACPI_PM1_REGISTER_WIDTH, 75 ACPI_FADT_OPTIONAL}, 76 77 {"Pm2ControlBlock", 78 ACPI_FADT_OFFSET(xpm2_control_block), 79 ACPI_FADT_OFFSET(pm2_control_block), 80 ACPI_FADT_OFFSET(pm2_control_length), 81 ACPI_PM2_REGISTER_WIDTH, 82 ACPI_FADT_SEPARATE_LENGTH}, 83 84 {"PmTimerBlock", 85 ACPI_FADT_OFFSET(xpm_timer_block), 86 ACPI_FADT_OFFSET(pm_timer_block), 87 ACPI_FADT_OFFSET(pm_timer_length), 88 ACPI_PM_TIMER_WIDTH, 89 ACPI_FADT_SEPARATE_LENGTH}, /* ACPI 5.0A: Timer is optional */ 90 91 {"Gpe0Block", 92 ACPI_FADT_OFFSET(xgpe0_block), 93 ACPI_FADT_OFFSET(gpe0_block), 94 ACPI_FADT_OFFSET(gpe0_block_length), 95 0, 96 ACPI_FADT_SEPARATE_LENGTH | ACPI_FADT_GPE_REGISTER}, 97 98 {"Gpe1Block", 99 ACPI_FADT_OFFSET(xgpe1_block), 100 ACPI_FADT_OFFSET(gpe1_block), 101 ACPI_FADT_OFFSET(gpe1_block_length), 102 0, 103 ACPI_FADT_SEPARATE_LENGTH | ACPI_FADT_GPE_REGISTER} 104}; 105 106#define ACPI_FADT_INFO_ENTRIES \ 107 (sizeof (fadt_info_table) / sizeof (struct acpi_fadt_info)) 108 109/* Table used to split Event Blocks into separate status/enable registers */ 110 111typedef struct acpi_fadt_pm_info { 112 struct acpi_generic_address *target; 113 u16 source; 114 u8 register_num; 115 116} acpi_fadt_pm_info; 117 118static struct acpi_fadt_pm_info fadt_pm_info_table[] = { 119 {&acpi_gbl_xpm1a_status, 120 ACPI_FADT_OFFSET(xpm1a_event_block), 121 0}, 122 123 {&acpi_gbl_xpm1a_enable, 124 ACPI_FADT_OFFSET(xpm1a_event_block), 125 1}, 126 127 {&acpi_gbl_xpm1b_status, 128 ACPI_FADT_OFFSET(xpm1b_event_block), 129 0}, 130 131 {&acpi_gbl_xpm1b_enable, 132 ACPI_FADT_OFFSET(xpm1b_event_block), 133 1} 134}; 135 136#define ACPI_FADT_PM_INFO_ENTRIES \ 137 (sizeof (fadt_pm_info_table) / sizeof (struct acpi_fadt_pm_info)) 138 139/******************************************************************************* 140 * 141 * FUNCTION: acpi_tb_init_generic_address 142 * 143 * PARAMETERS: generic_address - GAS struct to be initialized 144 * space_id - ACPI Space ID for this register 145 * byte_width - Width of this register 146 * address - Address of the register 147 * register_name - ASCII name of the ACPI register 148 * 149 * RETURN: None 150 * 151 * DESCRIPTION: Initialize a Generic Address Structure (GAS) 152 * See the ACPI specification for a full description and 153 * definition of this structure. 154 * 155 ******************************************************************************/ 156 157static void 158acpi_tb_init_generic_address(struct acpi_generic_address *generic_address, 159 u8 space_id, 160 u8 byte_width, 161 u64 address, const char *register_name, u8 flags) 162{ 163 u8 bit_width; 164 165 /* 166 * Bit width field in the GAS is only one byte long, 255 max. 167 * Check for bit_width overflow in GAS. 168 */ 169 bit_width = (u8)(byte_width * 8); 170 if (byte_width > 31) { /* (31*8)=248, (32*8)=256 */ 171 /* 172 * No error for GPE blocks, because we do not use the bit_width 173 * for GPEs, the legacy length (byte_width) is used instead to 174 * allow for a large number of GPEs. 175 */ 176 if (!(flags & ACPI_FADT_GPE_REGISTER)) { 177 ACPI_ERROR((AE_INFO, 178 "%s - 32-bit FADT register is too long (%u bytes, %u bits) " 179 "to convert to GAS struct - 255 bits max, truncating", 180 register_name, byte_width, 181 (byte_width * 8))); 182 } 183 184 bit_width = 255; 185 } 186 187 /* 188 * The 64-bit Address field is non-aligned in the byte packed 189 * GAS struct. 190 */ 191 ACPI_MOVE_64_TO_64(&generic_address->address, &address); 192 193 /* All other fields are byte-wide */ 194 195 generic_address->space_id = space_id; 196 generic_address->bit_width = bit_width; 197 generic_address->bit_offset = 0; 198 generic_address->access_width = 0; /* Access width ANY */ 199} 200 201/******************************************************************************* 202 * 203 * FUNCTION: acpi_tb_select_address 204 * 205 * PARAMETERS: register_name - ASCII name of the ACPI register 206 * address32 - 32-bit address of the register 207 * address64 - 64-bit address of the register 208 * 209 * RETURN: The resolved 64-bit address 210 * 211 * DESCRIPTION: Select between 32-bit and 64-bit versions of addresses within 212 * the FADT. Used for the FACS and DSDT addresses. 213 * 214 * NOTES: 215 * 216 * Check for FACS and DSDT address mismatches. An address mismatch between 217 * the 32-bit and 64-bit address fields (FIRMWARE_CTRL/X_FIRMWARE_CTRL and 218 * DSDT/X_DSDT) could be a corrupted address field or it might indicate 219 * the presence of two FACS or two DSDT tables. 220 * 221 * November 2013: 222 * By default, as per the ACPICA specification, a valid 64-bit address is 223 * used regardless of the value of the 32-bit address. However, this 224 * behavior can be overridden via the acpi_gbl_use32_bit_fadt_addresses flag. 225 * 226 ******************************************************************************/ 227 228static u64 229acpi_tb_select_address(char *register_name, u32 address32, u64 address64) 230{ 231 232 if (!address64) { 233 234 /* 64-bit address is zero, use 32-bit address */ 235 236 return ((u64)address32); 237 } 238 239 if (address32 && (address64 != (u64)address32)) { 240 241 /* Address mismatch between 32-bit and 64-bit versions */ 242 243 ACPI_BIOS_WARNING((AE_INFO, 244 "32/64X %s address mismatch in FADT: " 245 "0x%8.8X/0x%8.8X%8.8X, using %u-bit address", 246 register_name, address32, 247 ACPI_FORMAT_UINT64(address64), 248 acpi_gbl_use32_bit_fadt_addresses ? 32 : 249 64)); 250 251 /* 32-bit address override */ 252 253 if (acpi_gbl_use32_bit_fadt_addresses) { 254 return ((u64)address32); 255 } 256 } 257 258 /* Default is to use the 64-bit address */ 259 260 return (address64); 261} 262 263/******************************************************************************* 264 * 265 * FUNCTION: acpi_tb_parse_fadt 266 * 267 * PARAMETERS: None 268 * 269 * RETURN: None 270 * 271 * DESCRIPTION: Initialize the FADT, DSDT and FACS tables 272 * (FADT contains the addresses of the DSDT and FACS) 273 * 274 ******************************************************************************/ 275 276void acpi_tb_parse_fadt(void) 277{ 278 u32 length; 279 struct acpi_table_header *table; 280 struct acpi_table_desc *fadt_desc; 281 acpi_status status; 282 283 /* 284 * The FADT has multiple versions with different lengths, 285 * and it contains pointers to both the DSDT and FACS tables. 286 * 287 * Get a local copy of the FADT and convert it to a common format 288 * Map entire FADT, assumed to be smaller than one page. 289 */ 290 fadt_desc = &acpi_gbl_root_table_list.tables[acpi_gbl_fadt_index]; 291 status = acpi_tb_get_table(fadt_desc, &table); 292 if (ACPI_FAILURE(status)) { 293 return; 294 } 295 length = fadt_desc->length; 296 297 /* 298 * Validate the FADT checksum before we copy the table. Ignore 299 * checksum error as we want to try to get the DSDT and FACS. 300 */ 301 (void)acpi_ut_verify_checksum(table, length); 302 303 /* Create a local copy of the FADT in common ACPI 2.0+ format */ 304 305 acpi_tb_create_local_fadt(table, length); 306 307 /* All done with the real FADT, unmap it */ 308 309 acpi_tb_put_table(fadt_desc); 310 311 /* Obtain the DSDT and FACS tables via their addresses within the FADT */ 312 313 acpi_tb_install_standard_table((acpi_physical_address)acpi_gbl_FADT. 314 Xdsdt, 315 ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL, 316 NULL, FALSE, TRUE, &acpi_gbl_dsdt_index); 317 318 if (acpi_gbl_FADT.facs) { 319 acpi_tb_install_standard_table((acpi_physical_address) 320 acpi_gbl_FADT.facs, 321 ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL, 322 NULL, FALSE, TRUE, 323 &acpi_gbl_facs_index); 324 } 325 if (acpi_gbl_FADT.Xfacs) { 326 acpi_tb_install_standard_table((acpi_physical_address) 327 acpi_gbl_FADT.Xfacs, 328 ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL, 329 NULL, FALSE, TRUE, 330 &acpi_gbl_xfacs_index); 331 } 332} 333 334/******************************************************************************* 335 * 336 * FUNCTION: acpi_tb_create_local_fadt 337 * 338 * PARAMETERS: table - Pointer to BIOS FADT 339 * length - Length of the table 340 * 341 * RETURN: None 342 * 343 * DESCRIPTION: Get a local copy of the FADT and convert it to a common format. 344 * Performs validation on some important FADT fields. 345 * 346 * NOTE: We create a local copy of the FADT regardless of the version. 347 * 348 ******************************************************************************/ 349 350void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length) 351{ 352 /* 353 * Check if the FADT is larger than the largest table that we expect 354 * (typically the current ACPI specification version). If so, truncate 355 * the table, and issue a warning. 356 */ 357 if (length > sizeof(struct acpi_table_fadt)) { 358 ACPI_BIOS_WARNING((AE_INFO, 359 "FADT (revision %u) is longer than %s length, " 360 "truncating length %u to %u", 361 table->revision, ACPI_FADT_CONFORMANCE, 362 length, 363 (u32)sizeof(struct acpi_table_fadt))); 364 } 365 366 /* Clear the entire local FADT */ 367 368 memset(&acpi_gbl_FADT, 0, sizeof(struct acpi_table_fadt)); 369 370 /* Copy the original FADT, up to sizeof (struct acpi_table_fadt) */ 371 372 memcpy(&acpi_gbl_FADT, table, 373 ACPI_MIN(length, sizeof(struct acpi_table_fadt))); 374 375 /* Take a copy of the Hardware Reduced flag */ 376 377 acpi_gbl_reduced_hardware = FALSE; 378 if (acpi_gbl_FADT.flags & ACPI_FADT_HW_REDUCED) { 379 acpi_gbl_reduced_hardware = TRUE; 380 } 381 382 /* Convert the local copy of the FADT to the common internal format */ 383 384 acpi_tb_convert_fadt(); 385 386 /* Initialize the global ACPI register structures */ 387 388 acpi_tb_setup_fadt_registers(); 389} 390 391/******************************************************************************* 392 * 393 * FUNCTION: acpi_tb_convert_fadt 394 * 395 * PARAMETERS: none - acpi_gbl_FADT is used. 396 * 397 * RETURN: None 398 * 399 * DESCRIPTION: Converts all versions of the FADT to a common internal format. 400 * Expand 32-bit addresses to 64-bit as necessary. Also validate 401 * important fields within the FADT. 402 * 403 * NOTE: acpi_gbl_FADT must be of size (struct acpi_table_fadt), and must 404 * contain a copy of the actual BIOS-provided FADT. 405 * 406 * Notes on 64-bit register addresses: 407 * 408 * After this FADT conversion, later ACPICA code will only use the 64-bit "X" 409 * fields of the FADT for all ACPI register addresses. 410 * 411 * The 64-bit X fields are optional extensions to the original 32-bit FADT 412 * V1.0 fields. Even if they are present in the FADT, they are optional and 413 * are unused if the BIOS sets them to zero. Therefore, we must copy/expand 414 * 32-bit V1.0 fields to the 64-bit X fields if the 64-bit X field is originally 415 * zero. 416 * 417 * For ACPI 1.0 FADTs (that contain no 64-bit addresses), all 32-bit address 418 * fields are expanded to the corresponding 64-bit X fields in the internal 419 * common FADT. 420 * 421 * For ACPI 2.0+ FADTs, all valid (non-zero) 32-bit address fields are expanded 422 * to the corresponding 64-bit X fields, if the 64-bit field is originally 423 * zero. Adhering to the ACPI specification, we completely ignore the 32-bit 424 * field if the 64-bit field is valid, regardless of whether the host OS is 425 * 32-bit or 64-bit. 426 * 427 * Possible additional checks: 428 * (acpi_gbl_FADT.pm1_event_length >= 4) 429 * (acpi_gbl_FADT.pm1_control_length >= 2) 430 * (acpi_gbl_FADT.pm_timer_length >= 4) 431 * Gpe block lengths must be multiple of 2 432 * 433 ******************************************************************************/ 434 435static void acpi_tb_convert_fadt(void) 436{ 437 const char *name; 438 struct acpi_generic_address *address64; 439 u32 address32; 440 u8 length; 441 u8 flags; 442 u32 i; 443 444 /* 445 * For ACPI 1.0 FADTs (revision 1 or 2), ensure that reserved fields which 446 * should be zero are indeed zero. This will workaround BIOSs that 447 * inadvertently place values in these fields. 448 * 449 * The ACPI 1.0 reserved fields that will be zeroed are the bytes located 450 * at offset 45, 55, 95, and the word located at offset 109, 110. 451 * 452 * Note: The FADT revision value is unreliable. Only the length can be 453 * trusted. 454 */ 455 if (acpi_gbl_FADT.header.length <= ACPI_FADT_V2_SIZE) { 456 acpi_gbl_FADT.preferred_profile = 0; 457 acpi_gbl_FADT.pstate_control = 0; 458 acpi_gbl_FADT.cst_control = 0; 459 acpi_gbl_FADT.boot_flags = 0; 460 } 461 462 /* 463 * Now we can update the local FADT length to the length of the 464 * current FADT version as defined by the ACPI specification. 465 * Thus, we will have a common FADT internally. 466 */ 467 acpi_gbl_FADT.header.length = sizeof(struct acpi_table_fadt); 468 469 /* 470 * Expand the 32-bit DSDT addresses to 64-bit as necessary. 471 * Later ACPICA code will always use the X 64-bit field. 472 */ 473 acpi_gbl_FADT.Xdsdt = acpi_tb_select_address("DSDT", 474 acpi_gbl_FADT.dsdt, 475 acpi_gbl_FADT.Xdsdt); 476 477 /* If Hardware Reduced flag is set, we are all done */ 478 479 if (acpi_gbl_reduced_hardware) { 480 return; 481 } 482 483 /* Examine all of the 64-bit extended address fields (X fields) */ 484 485 for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) { 486 /* 487 * Get the 32-bit and 64-bit addresses, as well as the register 488 * length and register name. 489 */ 490 address32 = *ACPI_ADD_PTR(u32, 491 &acpi_gbl_FADT, 492 fadt_info_table[i].address32); 493 494 address64 = ACPI_ADD_PTR(struct acpi_generic_address, 495 &acpi_gbl_FADT, 496 fadt_info_table[i].address64); 497 498 length = *ACPI_ADD_PTR(u8, 499 &acpi_gbl_FADT, 500 fadt_info_table[i].length); 501 502 name = fadt_info_table[i].name; 503 flags = fadt_info_table[i].flags; 504 505 /* 506 * Expand the ACPI 1.0 32-bit addresses to the ACPI 2.0 64-bit "X" 507 * generic address structures as necessary. Later code will always use 508 * the 64-bit address structures. 509 * 510 * November 2013: 511 * Now always use the 64-bit address if it is valid (non-zero), in 512 * accordance with the ACPI specification which states that a 64-bit 513 * address supersedes the 32-bit version. This behavior can be 514 * overridden by the acpi_gbl_use32_bit_fadt_addresses flag. 515 * 516 * During 64-bit address construction and verification, 517 * these cases are handled: 518 * 519 * Address32 zero, Address64 [don't care] - Use Address64 520 * 521 * No override: if acpi_gbl_use32_bit_fadt_addresses is FALSE, and: 522 * Address32 non-zero, Address64 zero - Copy/use Address32 523 * Address32 non-zero == Address64 non-zero - Use Address64 524 * Address32 non-zero != Address64 non-zero - Warning, use Address64 525 * 526 * Override: if acpi_gbl_use32_bit_fadt_addresses is TRUE, and: 527 * Address32 non-zero, Address64 zero - Copy/use Address32 528 * Address32 non-zero == Address64 non-zero - Copy/use Address32 529 * Address32 non-zero != Address64 non-zero - Warning, copy/use Address32 530 * 531 * Note: space_id is always I/O for 32-bit legacy address fields 532 */ 533 if (address32) { 534 if (address64->address) { 535 if (address64->address != (u64)address32) { 536 537 /* Address mismatch */ 538 539 ACPI_BIOS_WARNING((AE_INFO, 540 "32/64X address mismatch in FADT/%s: " 541 "0x%8.8X/0x%8.8X%8.8X, using %u-bit address", 542 name, address32, 543 ACPI_FORMAT_UINT64 544 (address64->address), 545 acpi_gbl_use32_bit_fadt_addresses 546 ? 32 : 64)); 547 } 548 549 /* 550 * For each extended field, check for length mismatch 551 * between the legacy length field and the corresponding 552 * 64-bit X length field. 553 * Note: If the legacy length field is > 0xFF bits, ignore 554 * this check. (GPE registers can be larger than the 555 * 64-bit GAS structure can accommodate, 0xFF bits). 556 */ 557 if ((ACPI_MUL_8(length) <= ACPI_UINT8_MAX) && 558 (address64->bit_width != 559 ACPI_MUL_8(length))) { 560 ACPI_BIOS_WARNING((AE_INFO, 561 "32/64X length mismatch in FADT/%s: %u/%u", 562 name, 563 ACPI_MUL_8(length), 564 address64-> 565 bit_width)); 566 } 567 } 568 569 /* 570 * Hardware register access code always uses the 64-bit fields. 571 * So if the 64-bit field is zero or is to be overridden, 572 * initialize it with the 32-bit fields. 573 * Note that when the 32-bit address favor is specified, the 574 * 64-bit fields are always re-initialized so that 575 * access_size/bit_width/bit_offset fields can be correctly 576 * configured to the values to trigger a 32-bit compatible 577 * access mode in the hardware register access code. 578 */ 579 if (!address64->address 580 || acpi_gbl_use32_bit_fadt_addresses) { 581 acpi_tb_init_generic_address(address64, 582 ACPI_ADR_SPACE_SYSTEM_IO, 583 length, 584 (u64)address32, 585 name, flags); 586 } 587 } 588 589 if (fadt_info_table[i].flags & ACPI_FADT_REQUIRED) { 590 /* 591 * Field is required (Pm1a_event, Pm1a_control). 592 * Both the address and length must be non-zero. 593 */ 594 if (!address64->address || !length) { 595 ACPI_BIOS_ERROR((AE_INFO, 596 "Required FADT field %s has zero address and/or length: " 597 "0x%8.8X%8.8X/0x%X", 598 name, 599 ACPI_FORMAT_UINT64(address64-> 600 address), 601 length)); 602 } 603 } else if (fadt_info_table[i].flags & ACPI_FADT_SEPARATE_LENGTH) { 604 /* 605 * Field is optional (Pm2_control, GPE0, GPE1) AND has its own 606 * length field. If present, both the address and length must 607 * be valid. 608 */ 609 if ((address64->address && !length) || 610 (!address64->address && length)) { 611 ACPI_BIOS_WARNING((AE_INFO, 612 "Optional FADT field %s has valid %s but zero %s: " 613 "0x%8.8X%8.8X/0x%X", name, 614 (length ? "Length" : 615 "Address"), 616 (length ? "Address" : 617 "Length"), 618 ACPI_FORMAT_UINT64 619 (address64->address), 620 length)); 621 } 622 } 623 } 624} 625 626/******************************************************************************* 627 * 628 * FUNCTION: acpi_tb_setup_fadt_registers 629 * 630 * PARAMETERS: None, uses acpi_gbl_FADT. 631 * 632 * RETURN: None 633 * 634 * DESCRIPTION: Initialize global ACPI PM1 register definitions. Optionally, 635 * force FADT register definitions to their default lengths. 636 * 637 ******************************************************************************/ 638 639static void acpi_tb_setup_fadt_registers(void) 640{ 641 struct acpi_generic_address *target64; 642 struct acpi_generic_address *source64; 643 u8 pm1_register_byte_width; 644 u32 i; 645 646 /* 647 * Optionally check all register lengths against the default values and 648 * update them if they are incorrect. 649 */ 650 if (acpi_gbl_use_default_register_widths) { 651 for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) { 652 target64 = 653 ACPI_ADD_PTR(struct acpi_generic_address, 654 &acpi_gbl_FADT, 655 fadt_info_table[i].address64); 656 657 /* 658 * If a valid register (Address != 0) and the (default_length > 0) 659 * (Not a GPE register), then check the width against the default. 660 */ 661 if ((target64->address) && 662 (fadt_info_table[i].default_length > 0) && 663 (fadt_info_table[i].default_length != 664 target64->bit_width)) { 665 ACPI_BIOS_WARNING((AE_INFO, 666 "Invalid length for FADT/%s: %u, using default %u", 667 fadt_info_table[i].name, 668 target64->bit_width, 669 fadt_info_table[i]. 670 default_length)); 671 672 /* Incorrect size, set width to the default */ 673 674 target64->bit_width = 675 fadt_info_table[i].default_length; 676 } 677 } 678 } 679 680 /* 681 * Get the length of the individual PM1 registers (enable and status). 682 * Each register is defined to be (event block length / 2). Extra divide 683 * by 8 converts bits to bytes. 684 */ 685 pm1_register_byte_width = (u8) 686 ACPI_DIV_16(acpi_gbl_FADT.xpm1a_event_block.bit_width); 687 688 /* 689 * Calculate separate GAS structs for the PM1x (A/B) Status and Enable 690 * registers. These addresses do not appear (directly) in the FADT, so it 691 * is useful to pre-calculate them from the PM1 Event Block definitions. 692 * 693 * The PM event blocks are split into two register blocks, first is the 694 * PM Status Register block, followed immediately by the PM Enable 695 * Register block. Each is of length (pm1_event_length/2) 696 * 697 * Note: The PM1A event block is required by the ACPI specification. 698 * However, the PM1B event block is optional and is rarely, if ever, 699 * used. 700 */ 701 702 for (i = 0; i < ACPI_FADT_PM_INFO_ENTRIES; i++) { 703 source64 = 704 ACPI_ADD_PTR(struct acpi_generic_address, &acpi_gbl_FADT, 705 fadt_pm_info_table[i].source); 706 707 if (source64->address) { 708 acpi_tb_init_generic_address(fadt_pm_info_table[i]. 709 target, source64->space_id, 710 pm1_register_byte_width, 711 source64->address + 712 (fadt_pm_info_table[i]. 713 register_num * 714 pm1_register_byte_width), 715 "PmRegisters", 0); 716 } 717 } 718}
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