1 /* 2 * efi.c - EFI subsystem 3 * 4 * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com> 5 * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com> 6 * Copyright (C) 2013 Tom Gundersen <teg@jklm.no> 7 * 8 * This code registers /sys/firmware/efi{,/efivars} when EFI is supported, 9 * allowing the efivarfs to be mounted or the efivars module to be loaded. 10 * The existance of /sys/firmware/efi may also be used by userspace to 11 * determine that the system supports EFI. 12 * 13 * This file is released under the GPLv2. 14 */ 15 16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 17 18 #include <linux/kobject.h> 19 #include <linux/module.h> 20 #include <linux/init.h> 21 #include <linux/device.h> 22 #include <linux/efi.h> 23 #include <linux/of.h> 24 #include <linux/of_fdt.h> 25 #include <linux/io.h> 26 #include <linux/kexec.h> 27 #include <linux/platform_device.h> 28 #include <linux/random.h> 29 #include <linux/reboot.h> 30 #include <linux/slab.h> 31 #include <linux/acpi.h> 32 #include <linux/ucs2_string.h> 33 #include <linux/memblock.h> 34 35 #include <asm/early_ioremap.h> 36 37 struct efi __read_mostly efi = { 38 .mps = EFI_INVALID_TABLE_ADDR, 39 .acpi = EFI_INVALID_TABLE_ADDR, 40 .acpi20 = EFI_INVALID_TABLE_ADDR, 41 .smbios = EFI_INVALID_TABLE_ADDR, 42 .smbios3 = EFI_INVALID_TABLE_ADDR, 43 .sal_systab = EFI_INVALID_TABLE_ADDR, 44 .boot_info = EFI_INVALID_TABLE_ADDR, 45 .hcdp = EFI_INVALID_TABLE_ADDR, 46 .uga = EFI_INVALID_TABLE_ADDR, 47 .uv_systab = EFI_INVALID_TABLE_ADDR, 48 .fw_vendor = EFI_INVALID_TABLE_ADDR, 49 .runtime = EFI_INVALID_TABLE_ADDR, 50 .config_table = EFI_INVALID_TABLE_ADDR, 51 .esrt = EFI_INVALID_TABLE_ADDR, 52 .properties_table = EFI_INVALID_TABLE_ADDR, 53 .mem_attr_table = EFI_INVALID_TABLE_ADDR, 54 .rng_seed = EFI_INVALID_TABLE_ADDR, 55 .tpm_log = EFI_INVALID_TABLE_ADDR, 56 .mem_reserve = EFI_INVALID_TABLE_ADDR, 57 }; 58 EXPORT_SYMBOL(efi); 59 60 static unsigned long *efi_tables[] = { 61 &efi.mps, 62 &efi.acpi, 63 &efi.acpi20, 64 &efi.smbios, 65 &efi.smbios3, 66 &efi.sal_systab, 67 &efi.boot_info, 68 &efi.hcdp, 69 &efi.uga, 70 &efi.uv_systab, 71 &efi.fw_vendor, 72 &efi.runtime, 73 &efi.config_table, 74 &efi.esrt, 75 &efi.properties_table, 76 &efi.mem_attr_table, 77 }; 78 79 struct mm_struct efi_mm = { 80 .mm_rb = RB_ROOT, 81 .mm_users = ATOMIC_INIT(2), 82 .mm_count = ATOMIC_INIT(1), 83 .mmap_sem = __RWSEM_INITIALIZER(efi_mm.mmap_sem), 84 .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock), 85 .mmlist = LIST_HEAD_INIT(efi_mm.mmlist), 86 .cpu_bitmap = { [BITS_TO_LONGS(NR_CPUS)] = 0}, 87 }; 88 89 struct workqueue_struct *efi_rts_wq; 90 91 static bool disable_runtime; 92 static int __init setup_noefi(char *arg) 93 { 94 disable_runtime = true; 95 return 0; 96 } 97 early_param("noefi", setup_noefi); 98 99 bool efi_runtime_disabled(void) 100 { 101 return disable_runtime; 102 } 103 104 static int __init parse_efi_cmdline(char *str) 105 { 106 if (!str) { 107 pr_warn("need at least one option\n"); 108 return -EINVAL; 109 } 110 111 if (parse_option_str(str, "debug")) 112 set_bit(EFI_DBG, &efi.flags); 113 114 if (parse_option_str(str, "noruntime")) 115 disable_runtime = true; 116 117 return 0; 118 } 119 early_param("efi", parse_efi_cmdline); 120 121 struct kobject *efi_kobj; 122 123 /* 124 * Let's not leave out systab information that snuck into 125 * the efivars driver 126 * Note, do not add more fields in systab sysfs file as it breaks sysfs 127 * one value per file rule! 128 */ 129 static ssize_t systab_show(struct kobject *kobj, 130 struct kobj_attribute *attr, char *buf) 131 { 132 char *str = buf; 133 134 if (!kobj || !buf) 135 return -EINVAL; 136 137 if (efi.mps != EFI_INVALID_TABLE_ADDR) 138 str += sprintf(str, "MPS=0x%lx\n", efi.mps); 139 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR) 140 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20); 141 if (efi.acpi != EFI_INVALID_TABLE_ADDR) 142 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi); 143 /* 144 * If both SMBIOS and SMBIOS3 entry points are implemented, the 145 * SMBIOS3 entry point shall be preferred, so we list it first to 146 * let applications stop parsing after the first match. 147 */ 148 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR) 149 str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3); 150 if (efi.smbios != EFI_INVALID_TABLE_ADDR) 151 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios); 152 if (efi.hcdp != EFI_INVALID_TABLE_ADDR) 153 str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp); 154 if (efi.boot_info != EFI_INVALID_TABLE_ADDR) 155 str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info); 156 if (efi.uga != EFI_INVALID_TABLE_ADDR) 157 str += sprintf(str, "UGA=0x%lx\n", efi.uga); 158 159 return str - buf; 160 } 161 162 static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400); 163 164 #define EFI_FIELD(var) efi.var 165 166 #define EFI_ATTR_SHOW(name) \ 167 static ssize_t name##_show(struct kobject *kobj, \ 168 struct kobj_attribute *attr, char *buf) \ 169 { \ 170 return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \ 171 } 172 173 EFI_ATTR_SHOW(fw_vendor); 174 EFI_ATTR_SHOW(runtime); 175 EFI_ATTR_SHOW(config_table); 176 177 static ssize_t fw_platform_size_show(struct kobject *kobj, 178 struct kobj_attribute *attr, char *buf) 179 { 180 return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32); 181 } 182 183 static struct kobj_attribute efi_attr_fw_vendor = __ATTR_RO(fw_vendor); 184 static struct kobj_attribute efi_attr_runtime = __ATTR_RO(runtime); 185 static struct kobj_attribute efi_attr_config_table = __ATTR_RO(config_table); 186 static struct kobj_attribute efi_attr_fw_platform_size = 187 __ATTR_RO(fw_platform_size); 188 189 static struct attribute *efi_subsys_attrs[] = { 190 &efi_attr_systab.attr, 191 &efi_attr_fw_vendor.attr, 192 &efi_attr_runtime.attr, 193 &efi_attr_config_table.attr, 194 &efi_attr_fw_platform_size.attr, 195 NULL, 196 }; 197 198 static umode_t efi_attr_is_visible(struct kobject *kobj, 199 struct attribute *attr, int n) 200 { 201 if (attr == &efi_attr_fw_vendor.attr) { 202 if (efi_enabled(EFI_PARAVIRT) || 203 efi.fw_vendor == EFI_INVALID_TABLE_ADDR) 204 return 0; 205 } else if (attr == &efi_attr_runtime.attr) { 206 if (efi.runtime == EFI_INVALID_TABLE_ADDR) 207 return 0; 208 } else if (attr == &efi_attr_config_table.attr) { 209 if (efi.config_table == EFI_INVALID_TABLE_ADDR) 210 return 0; 211 } 212 213 return attr->mode; 214 } 215 216 static const struct attribute_group efi_subsys_attr_group = { 217 .attrs = efi_subsys_attrs, 218 .is_visible = efi_attr_is_visible, 219 }; 220 221 static struct efivars generic_efivars; 222 static struct efivar_operations generic_ops; 223 224 static int generic_ops_register(void) 225 { 226 generic_ops.get_variable = efi.get_variable; 227 generic_ops.set_variable = efi.set_variable; 228 generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking; 229 generic_ops.get_next_variable = efi.get_next_variable; 230 generic_ops.query_variable_store = efi_query_variable_store; 231 232 return efivars_register(&generic_efivars, &generic_ops, efi_kobj); 233 } 234 235 static void generic_ops_unregister(void) 236 { 237 efivars_unregister(&generic_efivars); 238 } 239 240 #if IS_ENABLED(CONFIG_ACPI) 241 #define EFIVAR_SSDT_NAME_MAX 16 242 static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata; 243 static int __init efivar_ssdt_setup(char *str) 244 { 245 if (strlen(str) < sizeof(efivar_ssdt)) 246 memcpy(efivar_ssdt, str, strlen(str)); 247 else 248 pr_warn("efivar_ssdt: name too long: %s\n", str); 249 return 0; 250 } 251 __setup("efivar_ssdt=", efivar_ssdt_setup); 252 253 static __init int efivar_ssdt_iter(efi_char16_t *name, efi_guid_t vendor, 254 unsigned long name_size, void *data) 255 { 256 struct efivar_entry *entry; 257 struct list_head *list = data; 258 char utf8_name[EFIVAR_SSDT_NAME_MAX]; 259 int limit = min_t(unsigned long, EFIVAR_SSDT_NAME_MAX, name_size); 260 261 ucs2_as_utf8(utf8_name, name, limit - 1); 262 if (strncmp(utf8_name, efivar_ssdt, limit) != 0) 263 return 0; 264 265 entry = kmalloc(sizeof(*entry), GFP_KERNEL); 266 if (!entry) 267 return 0; 268 269 memcpy(entry->var.VariableName, name, name_size); 270 memcpy(&entry->var.VendorGuid, &vendor, sizeof(efi_guid_t)); 271 272 efivar_entry_add(entry, list); 273 274 return 0; 275 } 276 277 static __init int efivar_ssdt_load(void) 278 { 279 LIST_HEAD(entries); 280 struct efivar_entry *entry, *aux; 281 unsigned long size; 282 void *data; 283 int ret; 284 285 ret = efivar_init(efivar_ssdt_iter, &entries, true, &entries); 286 287 list_for_each_entry_safe(entry, aux, &entries, list) { 288 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt, 289 &entry->var.VendorGuid); 290 291 list_del(&entry->list); 292 293 ret = efivar_entry_size(entry, &size); 294 if (ret) { 295 pr_err("failed to get var size\n"); 296 goto free_entry; 297 } 298 299 data = kmalloc(size, GFP_KERNEL); 300 if (!data) { 301 ret = -ENOMEM; 302 goto free_entry; 303 } 304 305 ret = efivar_entry_get(entry, NULL, &size, data); 306 if (ret) { 307 pr_err("failed to get var data\n"); 308 goto free_data; 309 } 310 311 ret = acpi_load_table(data); 312 if (ret) { 313 pr_err("failed to load table: %d\n", ret); 314 goto free_data; 315 } 316 317 goto free_entry; 318 319 free_data: 320 kfree(data); 321 322 free_entry: 323 kfree(entry); 324 } 325 326 return ret; 327 } 328 #else 329 static inline int efivar_ssdt_load(void) { return 0; } 330 #endif 331 332 /* 333 * We register the efi subsystem with the firmware subsystem and the 334 * efivars subsystem with the efi subsystem, if the system was booted with 335 * EFI. 336 */ 337 static int __init efisubsys_init(void) 338 { 339 int error; 340 341 if (!efi_enabled(EFI_BOOT)) 342 return 0; 343 344 /* 345 * Since we process only one efi_runtime_service() at a time, an 346 * ordered workqueue (which creates only one execution context) 347 * should suffice all our needs. 348 */ 349 efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0); 350 if (!efi_rts_wq) { 351 pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n"); 352 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); 353 return 0; 354 } 355 356 /* We register the efi directory at /sys/firmware/efi */ 357 efi_kobj = kobject_create_and_add("efi", firmware_kobj); 358 if (!efi_kobj) { 359 pr_err("efi: Firmware registration failed.\n"); 360 return -ENOMEM; 361 } 362 363 error = generic_ops_register(); 364 if (error) 365 goto err_put; 366 367 if (efi_enabled(EFI_RUNTIME_SERVICES)) 368 efivar_ssdt_load(); 369 370 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); 371 if (error) { 372 pr_err("efi: Sysfs attribute export failed with error %d.\n", 373 error); 374 goto err_unregister; 375 } 376 377 error = efi_runtime_map_init(efi_kobj); 378 if (error) 379 goto err_remove_group; 380 381 /* and the standard mountpoint for efivarfs */ 382 error = sysfs_create_mount_point(efi_kobj, "efivars"); 383 if (error) { 384 pr_err("efivars: Subsystem registration failed.\n"); 385 goto err_remove_group; 386 } 387 388 return 0; 389 390 err_remove_group: 391 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group); 392 err_unregister: 393 generic_ops_unregister(); 394 err_put: 395 kobject_put(efi_kobj); 396 return error; 397 } 398 399 subsys_initcall(efisubsys_init); 400 401 /* 402 * Find the efi memory descriptor for a given physical address. Given a 403 * physical address, determine if it exists within an EFI Memory Map entry, 404 * and if so, populate the supplied memory descriptor with the appropriate 405 * data. 406 */ 407 int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md) 408 { 409 efi_memory_desc_t *md; 410 411 if (!efi_enabled(EFI_MEMMAP)) { 412 pr_err_once("EFI_MEMMAP is not enabled.\n"); 413 return -EINVAL; 414 } 415 416 if (!out_md) { 417 pr_err_once("out_md is null.\n"); 418 return -EINVAL; 419 } 420 421 for_each_efi_memory_desc(md) { 422 u64 size; 423 u64 end; 424 425 size = md->num_pages << EFI_PAGE_SHIFT; 426 end = md->phys_addr + size; 427 if (phys_addr >= md->phys_addr && phys_addr < end) { 428 memcpy(out_md, md, sizeof(*out_md)); 429 return 0; 430 } 431 } 432 return -ENOENT; 433 } 434 435 /* 436 * Calculate the highest address of an efi memory descriptor. 437 */ 438 u64 __init efi_mem_desc_end(efi_memory_desc_t *md) 439 { 440 u64 size = md->num_pages << EFI_PAGE_SHIFT; 441 u64 end = md->phys_addr + size; 442 return end; 443 } 444 445 void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {} 446 447 /** 448 * efi_mem_reserve - Reserve an EFI memory region 449 * @addr: Physical address to reserve 450 * @size: Size of reservation 451 * 452 * Mark a region as reserved from general kernel allocation and 453 * prevent it being released by efi_free_boot_services(). 454 * 455 * This function should be called drivers once they've parsed EFI 456 * configuration tables to figure out where their data lives, e.g. 457 * efi_esrt_init(). 458 */ 459 void __init efi_mem_reserve(phys_addr_t addr, u64 size) 460 { 461 if (!memblock_is_region_reserved(addr, size)) 462 memblock_reserve(addr, size); 463 464 /* 465 * Some architectures (x86) reserve all boot services ranges 466 * until efi_free_boot_services() because of buggy firmware 467 * implementations. This means the above memblock_reserve() is 468 * superfluous on x86 and instead what it needs to do is 469 * ensure the @start, @size is not freed. 470 */ 471 efi_arch_mem_reserve(addr, size); 472 } 473 474 static __initdata efi_config_table_type_t common_tables[] = { 475 {ACPI_20_TABLE_GUID, "ACPI 2.0", &efi.acpi20}, 476 {ACPI_TABLE_GUID, "ACPI", &efi.acpi}, 477 {HCDP_TABLE_GUID, "HCDP", &efi.hcdp}, 478 {MPS_TABLE_GUID, "MPS", &efi.mps}, 479 {SAL_SYSTEM_TABLE_GUID, "SALsystab", &efi.sal_systab}, 480 {SMBIOS_TABLE_GUID, "SMBIOS", &efi.smbios}, 481 {SMBIOS3_TABLE_GUID, "SMBIOS 3.0", &efi.smbios3}, 482 {UGA_IO_PROTOCOL_GUID, "UGA", &efi.uga}, 483 {EFI_SYSTEM_RESOURCE_TABLE_GUID, "ESRT", &efi.esrt}, 484 {EFI_PROPERTIES_TABLE_GUID, "PROP", &efi.properties_table}, 485 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, "MEMATTR", &efi.mem_attr_table}, 486 {LINUX_EFI_RANDOM_SEED_TABLE_GUID, "RNG", &efi.rng_seed}, 487 {LINUX_EFI_TPM_EVENT_LOG_GUID, "TPMEventLog", &efi.tpm_log}, 488 {LINUX_EFI_MEMRESERVE_TABLE_GUID, "MEMRESERVE", &efi.mem_reserve}, 489 {NULL_GUID, NULL, NULL}, 490 }; 491 492 static __init int match_config_table(efi_guid_t *guid, 493 unsigned long table, 494 efi_config_table_type_t *table_types) 495 { 496 int i; 497 498 if (table_types) { 499 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) { 500 if (!efi_guidcmp(*guid, table_types[i].guid)) { 501 *(table_types[i].ptr) = table; 502 if (table_types[i].name) 503 pr_cont(" %s=0x%lx ", 504 table_types[i].name, table); 505 return 1; 506 } 507 } 508 } 509 510 return 0; 511 } 512 513 int __init efi_config_parse_tables(void *config_tables, int count, int sz, 514 efi_config_table_type_t *arch_tables) 515 { 516 void *tablep; 517 int i; 518 519 tablep = config_tables; 520 pr_info(""); 521 for (i = 0; i < count; i++) { 522 efi_guid_t guid; 523 unsigned long table; 524 525 if (efi_enabled(EFI_64BIT)) { 526 u64 table64; 527 guid = ((efi_config_table_64_t *)tablep)->guid; 528 table64 = ((efi_config_table_64_t *)tablep)->table; 529 table = table64; 530 #ifndef CONFIG_64BIT 531 if (table64 >> 32) { 532 pr_cont("\n"); 533 pr_err("Table located above 4GB, disabling EFI.\n"); 534 return -EINVAL; 535 } 536 #endif 537 } else { 538 guid = ((efi_config_table_32_t *)tablep)->guid; 539 table = ((efi_config_table_32_t *)tablep)->table; 540 } 541 542 if (!match_config_table(&guid, table, common_tables)) 543 match_config_table(&guid, table, arch_tables); 544 545 tablep += sz; 546 } 547 pr_cont("\n"); 548 set_bit(EFI_CONFIG_TABLES, &efi.flags); 549 550 if (efi.rng_seed != EFI_INVALID_TABLE_ADDR) { 551 struct linux_efi_random_seed *seed; 552 u32 size = 0; 553 554 seed = early_memremap(efi.rng_seed, sizeof(*seed)); 555 if (seed != NULL) { 556 size = seed->size; 557 early_memunmap(seed, sizeof(*seed)); 558 } else { 559 pr_err("Could not map UEFI random seed!\n"); 560 } 561 if (size > 0) { 562 seed = early_memremap(efi.rng_seed, 563 sizeof(*seed) + size); 564 if (seed != NULL) { 565 pr_notice("seeding entropy pool\n"); 566 add_device_randomness(seed->bits, seed->size); 567 early_memunmap(seed, sizeof(*seed) + size); 568 } else { 569 pr_err("Could not map UEFI random seed!\n"); 570 } 571 } 572 } 573 574 if (efi_enabled(EFI_MEMMAP)) 575 efi_memattr_init(); 576 577 efi_tpm_eventlog_init(); 578 579 /* Parse the EFI Properties table if it exists */ 580 if (efi.properties_table != EFI_INVALID_TABLE_ADDR) { 581 efi_properties_table_t *tbl; 582 583 tbl = early_memremap(efi.properties_table, sizeof(*tbl)); 584 if (tbl == NULL) { 585 pr_err("Could not map Properties table!\n"); 586 return -ENOMEM; 587 } 588 589 if (tbl->memory_protection_attribute & 590 EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA) 591 set_bit(EFI_NX_PE_DATA, &efi.flags); 592 593 early_memunmap(tbl, sizeof(*tbl)); 594 } 595 return 0; 596 } 597 598 int __init efi_apply_persistent_mem_reservations(void) 599 { 600 if (efi.mem_reserve != EFI_INVALID_TABLE_ADDR) { 601 unsigned long prsv = efi.mem_reserve; 602 603 while (prsv) { 604 struct linux_efi_memreserve *rsv; 605 606 /* reserve the entry itself */ 607 memblock_reserve(prsv, sizeof(*rsv)); 608 609 rsv = early_memremap(prsv, sizeof(*rsv)); 610 if (rsv == NULL) { 611 pr_err("Could not map UEFI memreserve entry!\n"); 612 return -ENOMEM; 613 } 614 615 if (rsv->size) 616 memblock_reserve(rsv->base, rsv->size); 617 618 prsv = rsv->next; 619 early_memunmap(rsv, sizeof(*rsv)); 620 } 621 } 622 623 return 0; 624 } 625 626 int __init efi_config_init(efi_config_table_type_t *arch_tables) 627 { 628 void *config_tables; 629 int sz, ret; 630 631 if (efi_enabled(EFI_64BIT)) 632 sz = sizeof(efi_config_table_64_t); 633 else 634 sz = sizeof(efi_config_table_32_t); 635 636 /* 637 * Let's see what config tables the firmware passed to us. 638 */ 639 config_tables = early_memremap(efi.systab->tables, 640 efi.systab->nr_tables * sz); 641 if (config_tables == NULL) { 642 pr_err("Could not map Configuration table!\n"); 643 return -ENOMEM; 644 } 645 646 ret = efi_config_parse_tables(config_tables, efi.systab->nr_tables, sz, 647 arch_tables); 648 649 early_memunmap(config_tables, efi.systab->nr_tables * sz); 650 return ret; 651 } 652 653 #ifdef CONFIG_EFI_VARS_MODULE 654 static int __init efi_load_efivars(void) 655 { 656 struct platform_device *pdev; 657 658 if (!efi_enabled(EFI_RUNTIME_SERVICES)) 659 return 0; 660 661 pdev = platform_device_register_simple("efivars", 0, NULL, 0); 662 return PTR_ERR_OR_ZERO(pdev); 663 } 664 device_initcall(efi_load_efivars); 665 #endif 666 667 #ifdef CONFIG_EFI_PARAMS_FROM_FDT 668 669 #define UEFI_PARAM(name, prop, field) \ 670 { \ 671 { name }, \ 672 { prop }, \ 673 offsetof(struct efi_fdt_params, field), \ 674 FIELD_SIZEOF(struct efi_fdt_params, field) \ 675 } 676 677 struct params { 678 const char name[32]; 679 const char propname[32]; 680 int offset; 681 int size; 682 }; 683 684 static __initdata struct params fdt_params[] = { 685 UEFI_PARAM("System Table", "linux,uefi-system-table", system_table), 686 UEFI_PARAM("MemMap Address", "linux,uefi-mmap-start", mmap), 687 UEFI_PARAM("MemMap Size", "linux,uefi-mmap-size", mmap_size), 688 UEFI_PARAM("MemMap Desc. Size", "linux,uefi-mmap-desc-size", desc_size), 689 UEFI_PARAM("MemMap Desc. Version", "linux,uefi-mmap-desc-ver", desc_ver) 690 }; 691 692 static __initdata struct params xen_fdt_params[] = { 693 UEFI_PARAM("System Table", "xen,uefi-system-table", system_table), 694 UEFI_PARAM("MemMap Address", "xen,uefi-mmap-start", mmap), 695 UEFI_PARAM("MemMap Size", "xen,uefi-mmap-size", mmap_size), 696 UEFI_PARAM("MemMap Desc. Size", "xen,uefi-mmap-desc-size", desc_size), 697 UEFI_PARAM("MemMap Desc. Version", "xen,uefi-mmap-desc-ver", desc_ver) 698 }; 699 700 #define EFI_FDT_PARAMS_SIZE ARRAY_SIZE(fdt_params) 701 702 static __initdata struct { 703 const char *uname; 704 const char *subnode; 705 struct params *params; 706 } dt_params[] = { 707 { "hypervisor", "uefi", xen_fdt_params }, 708 { "chosen", NULL, fdt_params }, 709 }; 710 711 struct param_info { 712 int found; 713 void *params; 714 const char *missing; 715 }; 716 717 static int __init __find_uefi_params(unsigned long node, 718 struct param_info *info, 719 struct params *params) 720 { 721 const void *prop; 722 void *dest; 723 u64 val; 724 int i, len; 725 726 for (i = 0; i < EFI_FDT_PARAMS_SIZE; i++) { 727 prop = of_get_flat_dt_prop(node, params[i].propname, &len); 728 if (!prop) { 729 info->missing = params[i].name; 730 return 0; 731 } 732 733 dest = info->params + params[i].offset; 734 info->found++; 735 736 val = of_read_number(prop, len / sizeof(u32)); 737 738 if (params[i].size == sizeof(u32)) 739 *(u32 *)dest = val; 740 else 741 *(u64 *)dest = val; 742 743 if (efi_enabled(EFI_DBG)) 744 pr_info(" %s: 0x%0*llx\n", params[i].name, 745 params[i].size * 2, val); 746 } 747 748 return 1; 749 } 750 751 static int __init fdt_find_uefi_params(unsigned long node, const char *uname, 752 int depth, void *data) 753 { 754 struct param_info *info = data; 755 int i; 756 757 for (i = 0; i < ARRAY_SIZE(dt_params); i++) { 758 const char *subnode = dt_params[i].subnode; 759 760 if (depth != 1 || strcmp(uname, dt_params[i].uname) != 0) { 761 info->missing = dt_params[i].params[0].name; 762 continue; 763 } 764 765 if (subnode) { 766 int err = of_get_flat_dt_subnode_by_name(node, subnode); 767 768 if (err < 0) 769 return 0; 770 771 node = err; 772 } 773 774 return __find_uefi_params(node, info, dt_params[i].params); 775 } 776 777 return 0; 778 } 779 780 int __init efi_get_fdt_params(struct efi_fdt_params *params) 781 { 782 struct param_info info; 783 int ret; 784 785 pr_info("Getting EFI parameters from FDT:\n"); 786 787 info.found = 0; 788 info.params = params; 789 790 ret = of_scan_flat_dt(fdt_find_uefi_params, &info); 791 if (!info.found) 792 pr_info("UEFI not found.\n"); 793 else if (!ret) 794 pr_err("Can't find '%s' in device tree!\n", 795 info.missing); 796 797 return ret; 798 } 799 #endif /* CONFIG_EFI_PARAMS_FROM_FDT */ 800 801 static __initdata char memory_type_name[][20] = { 802 "Reserved", 803 "Loader Code", 804 "Loader Data", 805 "Boot Code", 806 "Boot Data", 807 "Runtime Code", 808 "Runtime Data", 809 "Conventional Memory", 810 "Unusable Memory", 811 "ACPI Reclaim Memory", 812 "ACPI Memory NVS", 813 "Memory Mapped I/O", 814 "MMIO Port Space", 815 "PAL Code", 816 "Persistent Memory", 817 }; 818 819 char * __init efi_md_typeattr_format(char *buf, size_t size, 820 const efi_memory_desc_t *md) 821 { 822 char *pos; 823 int type_len; 824 u64 attr; 825 826 pos = buf; 827 if (md->type >= ARRAY_SIZE(memory_type_name)) 828 type_len = snprintf(pos, size, "[type=%u", md->type); 829 else 830 type_len = snprintf(pos, size, "[%-*s", 831 (int)(sizeof(memory_type_name[0]) - 1), 832 memory_type_name[md->type]); 833 if (type_len >= size) 834 return buf; 835 836 pos += type_len; 837 size -= type_len; 838 839 attr = md->attribute; 840 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT | 841 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO | 842 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP | 843 EFI_MEMORY_NV | 844 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE)) 845 snprintf(pos, size, "|attr=0x%016llx]", 846 (unsigned long long)attr); 847 else 848 snprintf(pos, size, 849 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]", 850 attr & EFI_MEMORY_RUNTIME ? "RUN" : "", 851 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "", 852 attr & EFI_MEMORY_NV ? "NV" : "", 853 attr & EFI_MEMORY_XP ? "XP" : "", 854 attr & EFI_MEMORY_RP ? "RP" : "", 855 attr & EFI_MEMORY_WP ? "WP" : "", 856 attr & EFI_MEMORY_RO ? "RO" : "", 857 attr & EFI_MEMORY_UCE ? "UCE" : "", 858 attr & EFI_MEMORY_WB ? "WB" : "", 859 attr & EFI_MEMORY_WT ? "WT" : "", 860 attr & EFI_MEMORY_WC ? "WC" : "", 861 attr & EFI_MEMORY_UC ? "UC" : ""); 862 return buf; 863 } 864 865 /* 866 * IA64 has a funky EFI memory map that doesn't work the same way as 867 * other architectures. 868 */ 869 #ifndef CONFIG_IA64 870 /* 871 * efi_mem_attributes - lookup memmap attributes for physical address 872 * @phys_addr: the physical address to lookup 873 * 874 * Search in the EFI memory map for the region covering 875 * @phys_addr. Returns the EFI memory attributes if the region 876 * was found in the memory map, 0 otherwise. 877 */ 878 u64 efi_mem_attributes(unsigned long phys_addr) 879 { 880 efi_memory_desc_t *md; 881 882 if (!efi_enabled(EFI_MEMMAP)) 883 return 0; 884 885 for_each_efi_memory_desc(md) { 886 if ((md->phys_addr <= phys_addr) && 887 (phys_addr < (md->phys_addr + 888 (md->num_pages << EFI_PAGE_SHIFT)))) 889 return md->attribute; 890 } 891 return 0; 892 } 893 894 /* 895 * efi_mem_type - lookup memmap type for physical address 896 * @phys_addr: the physical address to lookup 897 * 898 * Search in the EFI memory map for the region covering @phys_addr. 899 * Returns the EFI memory type if the region was found in the memory 900 * map, EFI_RESERVED_TYPE (zero) otherwise. 901 */ 902 int efi_mem_type(unsigned long phys_addr) 903 { 904 const efi_memory_desc_t *md; 905 906 if (!efi_enabled(EFI_MEMMAP)) 907 return -ENOTSUPP; 908 909 for_each_efi_memory_desc(md) { 910 if ((md->phys_addr <= phys_addr) && 911 (phys_addr < (md->phys_addr + 912 (md->num_pages << EFI_PAGE_SHIFT)))) 913 return md->type; 914 } 915 return -EINVAL; 916 } 917 #endif 918 919 int efi_status_to_err(efi_status_t status) 920 { 921 int err; 922 923 switch (status) { 924 case EFI_SUCCESS: 925 err = 0; 926 break; 927 case EFI_INVALID_PARAMETER: 928 err = -EINVAL; 929 break; 930 case EFI_OUT_OF_RESOURCES: 931 err = -ENOSPC; 932 break; 933 case EFI_DEVICE_ERROR: 934 err = -EIO; 935 break; 936 case EFI_WRITE_PROTECTED: 937 err = -EROFS; 938 break; 939 case EFI_SECURITY_VIOLATION: 940 err = -EACCES; 941 break; 942 case EFI_NOT_FOUND: 943 err = -ENOENT; 944 break; 945 case EFI_ABORTED: 946 err = -EINTR; 947 break; 948 default: 949 err = -EINVAL; 950 } 951 952 return err; 953 } 954 955 bool efi_is_table_address(unsigned long phys_addr) 956 { 957 unsigned int i; 958 959 if (phys_addr == EFI_INVALID_TABLE_ADDR) 960 return false; 961 962 for (i = 0; i < ARRAY_SIZE(efi_tables); i++) 963 if (*(efi_tables[i]) == phys_addr) 964 return true; 965 966 return false; 967 } 968 969 static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock); 970 static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init; 971 972 int efi_mem_reserve_persistent(phys_addr_t addr, u64 size) 973 { 974 struct linux_efi_memreserve *rsv; 975 976 if (!efi_memreserve_root) 977 return -ENODEV; 978 979 rsv = kmalloc(sizeof(*rsv), GFP_ATOMIC); 980 if (!rsv) 981 return -ENOMEM; 982 983 rsv->base = addr; 984 rsv->size = size; 985 986 spin_lock(&efi_mem_reserve_persistent_lock); 987 rsv->next = efi_memreserve_root->next; 988 efi_memreserve_root->next = __pa(rsv); 989 spin_unlock(&efi_mem_reserve_persistent_lock); 990 991 return 0; 992 } 993 994 static int __init efi_memreserve_root_init(void) 995 { 996 if (efi.mem_reserve == EFI_INVALID_TABLE_ADDR) 997 return -ENODEV; 998 999 efi_memreserve_root = memremap(efi.mem_reserve, 1000 sizeof(*efi_memreserve_root), 1001 MEMREMAP_WB); 1002 if (!efi_memreserve_root) 1003 return -ENOMEM; 1004 return 0; 1005 } 1006 early_initcall(efi_memreserve_root_init); 1007 1008 #ifdef CONFIG_KEXEC 1009 static int update_efi_random_seed(struct notifier_block *nb, 1010 unsigned long code, void *unused) 1011 { 1012 struct linux_efi_random_seed *seed; 1013 u32 size = 0; 1014 1015 if (!kexec_in_progress) 1016 return NOTIFY_DONE; 1017 1018 seed = memremap(efi.rng_seed, sizeof(*seed), MEMREMAP_WB); 1019 if (seed != NULL) { 1020 size = min(seed->size, EFI_RANDOM_SEED_SIZE); 1021 memunmap(seed); 1022 } else { 1023 pr_err("Could not map UEFI random seed!\n"); 1024 } 1025 if (size > 0) { 1026 seed = memremap(efi.rng_seed, sizeof(*seed) + size, 1027 MEMREMAP_WB); 1028 if (seed != NULL) { 1029 seed->size = size; 1030 get_random_bytes(seed->bits, seed->size); 1031 memunmap(seed); 1032 } else { 1033 pr_err("Could not map UEFI random seed!\n"); 1034 } 1035 } 1036 return NOTIFY_DONE; 1037 } 1038 1039 static struct notifier_block efi_random_seed_nb = { 1040 .notifier_call = update_efi_random_seed, 1041 }; 1042 1043 static int register_update_efi_random_seed(void) 1044 { 1045 if (efi.rng_seed == EFI_INVALID_TABLE_ADDR) 1046 return 0; 1047 return register_reboot_notifier(&efi_random_seed_nb); 1048 } 1049 late_initcall(register_update_efi_random_seed); 1050 #endif 1051