2 * efi.c - EFI subsystem
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>
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.
13 * This file is released under the GPLv2.
16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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>
24 #include <linux/of_fdt.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>
35 #include <asm/early_ioremap.h>
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
59 static unsigned long *efi_tables[] = {
74 &efi.properties_table,
78 struct mm_struct efi_mm = {
80 .mm_users = ATOMIC_INIT(2),
81 .mm_count = ATOMIC_INIT(1),
82 .mmap_sem = __RWSEM_INITIALIZER(efi_mm.mmap_sem),
83 .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock),
84 .mmlist = LIST_HEAD_INIT(efi_mm.mmlist),
87 struct workqueue_struct *efi_rts_wq;
89 static bool disable_runtime;
90 static int __init setup_noefi(char *arg)
92 disable_runtime = true;
95 early_param("noefi", setup_noefi);
97 bool efi_runtime_disabled(void)
99 return disable_runtime;
102 static int __init parse_efi_cmdline(char *str)
105 pr_warn("need at least one option\n");
109 if (parse_option_str(str, "debug"))
110 set_bit(EFI_DBG, &efi.flags);
112 if (parse_option_str(str, "noruntime"))
113 disable_runtime = true;
117 early_param("efi", parse_efi_cmdline);
119 struct kobject *efi_kobj;
122 * Let's not leave out systab information that snuck into
124 * Note, do not add more fields in systab sysfs file as it breaks sysfs
125 * one value per file rule!
127 static ssize_t systab_show(struct kobject *kobj,
128 struct kobj_attribute *attr, char *buf)
135 if (efi.mps != EFI_INVALID_TABLE_ADDR)
136 str += sprintf(str, "MPS=0x%lx\n", efi.mps);
137 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
138 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
139 if (efi.acpi != EFI_INVALID_TABLE_ADDR)
140 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
142 * If both SMBIOS and SMBIOS3 entry points are implemented, the
143 * SMBIOS3 entry point shall be preferred, so we list it first to
144 * let applications stop parsing after the first match.
146 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
147 str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
148 if (efi.smbios != EFI_INVALID_TABLE_ADDR)
149 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
150 if (efi.hcdp != EFI_INVALID_TABLE_ADDR)
151 str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp);
152 if (efi.boot_info != EFI_INVALID_TABLE_ADDR)
153 str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info);
154 if (efi.uga != EFI_INVALID_TABLE_ADDR)
155 str += sprintf(str, "UGA=0x%lx\n", efi.uga);
160 static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400);
162 #define EFI_FIELD(var) efi.var
164 #define EFI_ATTR_SHOW(name) \
165 static ssize_t name##_show(struct kobject *kobj, \
166 struct kobj_attribute *attr, char *buf) \
168 return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \
171 EFI_ATTR_SHOW(fw_vendor);
172 EFI_ATTR_SHOW(runtime);
173 EFI_ATTR_SHOW(config_table);
175 static ssize_t fw_platform_size_show(struct kobject *kobj,
176 struct kobj_attribute *attr, char *buf)
178 return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
181 static struct kobj_attribute efi_attr_fw_vendor = __ATTR_RO(fw_vendor);
182 static struct kobj_attribute efi_attr_runtime = __ATTR_RO(runtime);
183 static struct kobj_attribute efi_attr_config_table = __ATTR_RO(config_table);
184 static struct kobj_attribute efi_attr_fw_platform_size =
185 __ATTR_RO(fw_platform_size);
187 static struct attribute *efi_subsys_attrs[] = {
188 &efi_attr_systab.attr,
189 &efi_attr_fw_vendor.attr,
190 &efi_attr_runtime.attr,
191 &efi_attr_config_table.attr,
192 &efi_attr_fw_platform_size.attr,
196 static umode_t efi_attr_is_visible(struct kobject *kobj,
197 struct attribute *attr, int n)
199 if (attr == &efi_attr_fw_vendor.attr) {
200 if (efi_enabled(EFI_PARAVIRT) ||
201 efi.fw_vendor == EFI_INVALID_TABLE_ADDR)
203 } else if (attr == &efi_attr_runtime.attr) {
204 if (efi.runtime == EFI_INVALID_TABLE_ADDR)
206 } else if (attr == &efi_attr_config_table.attr) {
207 if (efi.config_table == EFI_INVALID_TABLE_ADDR)
214 static const struct attribute_group efi_subsys_attr_group = {
215 .attrs = efi_subsys_attrs,
216 .is_visible = efi_attr_is_visible,
219 static struct efivars generic_efivars;
220 static struct efivar_operations generic_ops;
222 static int generic_ops_register(void)
224 generic_ops.get_variable = efi.get_variable;
225 generic_ops.set_variable = efi.set_variable;
226 generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
227 generic_ops.get_next_variable = efi.get_next_variable;
228 generic_ops.query_variable_store = efi_query_variable_store;
230 return efivars_register(&generic_efivars, &generic_ops, efi_kobj);
233 static void generic_ops_unregister(void)
235 efivars_unregister(&generic_efivars);
238 #if IS_ENABLED(CONFIG_ACPI)
239 #define EFIVAR_SSDT_NAME_MAX 16
240 static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
241 static int __init efivar_ssdt_setup(char *str)
243 if (strlen(str) < sizeof(efivar_ssdt))
244 memcpy(efivar_ssdt, str, strlen(str));
246 pr_warn("efivar_ssdt: name too long: %s\n", str);
249 __setup("efivar_ssdt=", efivar_ssdt_setup);
251 static __init int efivar_ssdt_iter(efi_char16_t *name, efi_guid_t vendor,
252 unsigned long name_size, void *data)
254 struct efivar_entry *entry;
255 struct list_head *list = data;
256 char utf8_name[EFIVAR_SSDT_NAME_MAX];
257 int limit = min_t(unsigned long, EFIVAR_SSDT_NAME_MAX, name_size);
259 ucs2_as_utf8(utf8_name, name, limit - 1);
260 if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
263 entry = kmalloc(sizeof(*entry), GFP_KERNEL);
267 memcpy(entry->var.VariableName, name, name_size);
268 memcpy(&entry->var.VendorGuid, &vendor, sizeof(efi_guid_t));
270 efivar_entry_add(entry, list);
275 static __init int efivar_ssdt_load(void)
278 struct efivar_entry *entry, *aux;
283 ret = efivar_init(efivar_ssdt_iter, &entries, true, &entries);
285 list_for_each_entry_safe(entry, aux, &entries, list) {
286 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt,
287 &entry->var.VendorGuid);
289 list_del(&entry->list);
291 ret = efivar_entry_size(entry, &size);
293 pr_err("failed to get var size\n");
297 data = kmalloc(size, GFP_KERNEL);
303 ret = efivar_entry_get(entry, NULL, &size, data);
305 pr_err("failed to get var data\n");
309 ret = acpi_load_table(data);
311 pr_err("failed to load table: %d\n", ret);
327 static inline int efivar_ssdt_load(void) { return 0; }
331 * We register the efi subsystem with the firmware subsystem and the
332 * efivars subsystem with the efi subsystem, if the system was booted with
335 static int __init efisubsys_init(void)
339 if (!efi_enabled(EFI_BOOT))
343 * Since we process only one efi_runtime_service() at a time, an
344 * ordered workqueue (which creates only one execution context)
345 * should suffice all our needs.
347 efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0);
349 pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n");
350 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
354 /* We register the efi directory at /sys/firmware/efi */
355 efi_kobj = kobject_create_and_add("efi", firmware_kobj);
357 pr_err("efi: Firmware registration failed.\n");
361 error = generic_ops_register();
365 if (efi_enabled(EFI_RUNTIME_SERVICES))
368 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
370 pr_err("efi: Sysfs attribute export failed with error %d.\n",
375 error = efi_runtime_map_init(efi_kobj);
377 goto err_remove_group;
379 /* and the standard mountpoint for efivarfs */
380 error = sysfs_create_mount_point(efi_kobj, "efivars");
382 pr_err("efivars: Subsystem registration failed.\n");
383 goto err_remove_group;
389 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
391 generic_ops_unregister();
393 kobject_put(efi_kobj);
397 subsys_initcall(efisubsys_init);
400 * Find the efi memory descriptor for a given physical address. Given a
401 * physical address, determine if it exists within an EFI Memory Map entry,
402 * and if so, populate the supplied memory descriptor with the appropriate
405 int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
407 efi_memory_desc_t *md;
409 if (!efi_enabled(EFI_MEMMAP)) {
410 pr_err_once("EFI_MEMMAP is not enabled.\n");
415 pr_err_once("out_md is null.\n");
419 for_each_efi_memory_desc(md) {
423 size = md->num_pages << EFI_PAGE_SHIFT;
424 end = md->phys_addr + size;
425 if (phys_addr >= md->phys_addr && phys_addr < end) {
426 memcpy(out_md, md, sizeof(*out_md));
434 * Calculate the highest address of an efi memory descriptor.
436 u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
438 u64 size = md->num_pages << EFI_PAGE_SHIFT;
439 u64 end = md->phys_addr + size;
443 void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {}
446 * efi_mem_reserve - Reserve an EFI memory region
447 * @addr: Physical address to reserve
448 * @size: Size of reservation
450 * Mark a region as reserved from general kernel allocation and
451 * prevent it being released by efi_free_boot_services().
453 * This function should be called drivers once they've parsed EFI
454 * configuration tables to figure out where their data lives, e.g.
457 void __init efi_mem_reserve(phys_addr_t addr, u64 size)
459 if (!memblock_is_region_reserved(addr, size))
460 memblock_reserve(addr, size);
463 * Some architectures (x86) reserve all boot services ranges
464 * until efi_free_boot_services() because of buggy firmware
465 * implementations. This means the above memblock_reserve() is
466 * superfluous on x86 and instead what it needs to do is
467 * ensure the @start, @size is not freed.
469 efi_arch_mem_reserve(addr, size);
472 static __initdata efi_config_table_type_t common_tables[] = {
473 {ACPI_20_TABLE_GUID, "ACPI 2.0", &efi.acpi20},
474 {ACPI_TABLE_GUID, "ACPI", &efi.acpi},
475 {HCDP_TABLE_GUID, "HCDP", &efi.hcdp},
476 {MPS_TABLE_GUID, "MPS", &efi.mps},
477 {SAL_SYSTEM_TABLE_GUID, "SALsystab", &efi.sal_systab},
478 {SMBIOS_TABLE_GUID, "SMBIOS", &efi.smbios},
479 {SMBIOS3_TABLE_GUID, "SMBIOS 3.0", &efi.smbios3},
480 {UGA_IO_PROTOCOL_GUID, "UGA", &efi.uga},
481 {EFI_SYSTEM_RESOURCE_TABLE_GUID, "ESRT", &efi.esrt},
482 {EFI_PROPERTIES_TABLE_GUID, "PROP", &efi.properties_table},
483 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, "MEMATTR", &efi.mem_attr_table},
484 {LINUX_EFI_RANDOM_SEED_TABLE_GUID, "RNG", &efi.rng_seed},
485 {LINUX_EFI_TPM_EVENT_LOG_GUID, "TPMEventLog", &efi.tpm_log},
486 {NULL_GUID, NULL, NULL},
489 static __init int match_config_table(efi_guid_t *guid,
491 efi_config_table_type_t *table_types)
496 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
497 if (!efi_guidcmp(*guid, table_types[i].guid)) {
498 *(table_types[i].ptr) = table;
499 if (table_types[i].name)
500 pr_cont(" %s=0x%lx ",
501 table_types[i].name, table);
510 int __init efi_config_parse_tables(void *config_tables, int count, int sz,
511 efi_config_table_type_t *arch_tables)
516 tablep = config_tables;
518 for (i = 0; i < count; i++) {
522 if (efi_enabled(EFI_64BIT)) {
524 guid = ((efi_config_table_64_t *)tablep)->guid;
525 table64 = ((efi_config_table_64_t *)tablep)->table;
530 pr_err("Table located above 4GB, disabling EFI.\n");
535 guid = ((efi_config_table_32_t *)tablep)->guid;
536 table = ((efi_config_table_32_t *)tablep)->table;
539 if (!match_config_table(&guid, table, common_tables))
540 match_config_table(&guid, table, arch_tables);
545 set_bit(EFI_CONFIG_TABLES, &efi.flags);
547 if (efi.rng_seed != EFI_INVALID_TABLE_ADDR) {
548 struct linux_efi_random_seed *seed;
551 seed = early_memremap(efi.rng_seed, sizeof(*seed));
554 early_memunmap(seed, sizeof(*seed));
556 pr_err("Could not map UEFI random seed!\n");
559 seed = early_memremap(efi.rng_seed,
560 sizeof(*seed) + size);
562 pr_notice("seeding entropy pool\n");
563 add_device_randomness(seed->bits, seed->size);
564 early_memunmap(seed, sizeof(*seed) + size);
566 pr_err("Could not map UEFI random seed!\n");
571 if (efi_enabled(EFI_MEMMAP))
574 efi_tpm_eventlog_init();
576 /* Parse the EFI Properties table if it exists */
577 if (efi.properties_table != EFI_INVALID_TABLE_ADDR) {
578 efi_properties_table_t *tbl;
580 tbl = early_memremap(efi.properties_table, sizeof(*tbl));
582 pr_err("Could not map Properties table!\n");
586 if (tbl->memory_protection_attribute &
587 EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA)
588 set_bit(EFI_NX_PE_DATA, &efi.flags);
590 early_memunmap(tbl, sizeof(*tbl));
596 int __init efi_config_init(efi_config_table_type_t *arch_tables)
601 if (efi_enabled(EFI_64BIT))
602 sz = sizeof(efi_config_table_64_t);
604 sz = sizeof(efi_config_table_32_t);
607 * Let's see what config tables the firmware passed to us.
609 config_tables = early_memremap(efi.systab->tables,
610 efi.systab->nr_tables * sz);
611 if (config_tables == NULL) {
612 pr_err("Could not map Configuration table!\n");
616 ret = efi_config_parse_tables(config_tables, efi.systab->nr_tables, sz,
619 early_memunmap(config_tables, efi.systab->nr_tables * sz);
623 #ifdef CONFIG_EFI_VARS_MODULE
624 static int __init efi_load_efivars(void)
626 struct platform_device *pdev;
628 if (!efi_enabled(EFI_RUNTIME_SERVICES))
631 pdev = platform_device_register_simple("efivars", 0, NULL, 0);
632 return PTR_ERR_OR_ZERO(pdev);
634 device_initcall(efi_load_efivars);
637 #ifdef CONFIG_EFI_PARAMS_FROM_FDT
639 #define UEFI_PARAM(name, prop, field) \
643 offsetof(struct efi_fdt_params, field), \
644 FIELD_SIZEOF(struct efi_fdt_params, field) \
649 const char propname[32];
654 static __initdata struct params fdt_params[] = {
655 UEFI_PARAM("System Table", "linux,uefi-system-table", system_table),
656 UEFI_PARAM("MemMap Address", "linux,uefi-mmap-start", mmap),
657 UEFI_PARAM("MemMap Size", "linux,uefi-mmap-size", mmap_size),
658 UEFI_PARAM("MemMap Desc. Size", "linux,uefi-mmap-desc-size", desc_size),
659 UEFI_PARAM("MemMap Desc. Version", "linux,uefi-mmap-desc-ver", desc_ver)
662 static __initdata struct params xen_fdt_params[] = {
663 UEFI_PARAM("System Table", "xen,uefi-system-table", system_table),
664 UEFI_PARAM("MemMap Address", "xen,uefi-mmap-start", mmap),
665 UEFI_PARAM("MemMap Size", "xen,uefi-mmap-size", mmap_size),
666 UEFI_PARAM("MemMap Desc. Size", "xen,uefi-mmap-desc-size", desc_size),
667 UEFI_PARAM("MemMap Desc. Version", "xen,uefi-mmap-desc-ver", desc_ver)
670 #define EFI_FDT_PARAMS_SIZE ARRAY_SIZE(fdt_params)
672 static __initdata struct {
675 struct params *params;
677 { "hypervisor", "uefi", xen_fdt_params },
678 { "chosen", NULL, fdt_params },
687 static int __init __find_uefi_params(unsigned long node,
688 struct param_info *info,
689 struct params *params)
696 for (i = 0; i < EFI_FDT_PARAMS_SIZE; i++) {
697 prop = of_get_flat_dt_prop(node, params[i].propname, &len);
699 info->missing = params[i].name;
703 dest = info->params + params[i].offset;
706 val = of_read_number(prop, len / sizeof(u32));
708 if (params[i].size == sizeof(u32))
713 if (efi_enabled(EFI_DBG))
714 pr_info(" %s: 0x%0*llx\n", params[i].name,
715 params[i].size * 2, val);
721 static int __init fdt_find_uefi_params(unsigned long node, const char *uname,
722 int depth, void *data)
724 struct param_info *info = data;
727 for (i = 0; i < ARRAY_SIZE(dt_params); i++) {
728 const char *subnode = dt_params[i].subnode;
730 if (depth != 1 || strcmp(uname, dt_params[i].uname) != 0) {
731 info->missing = dt_params[i].params[0].name;
736 int err = of_get_flat_dt_subnode_by_name(node, subnode);
744 return __find_uefi_params(node, info, dt_params[i].params);
750 int __init efi_get_fdt_params(struct efi_fdt_params *params)
752 struct param_info info;
755 pr_info("Getting EFI parameters from FDT:\n");
758 info.params = params;
760 ret = of_scan_flat_dt(fdt_find_uefi_params, &info);
762 pr_info("UEFI not found.\n");
764 pr_err("Can't find '%s' in device tree!\n",
769 #endif /* CONFIG_EFI_PARAMS_FROM_FDT */
771 static __initdata char memory_type_name[][20] = {
779 "Conventional Memory",
781 "ACPI Reclaim Memory",
789 char * __init efi_md_typeattr_format(char *buf, size_t size,
790 const efi_memory_desc_t *md)
797 if (md->type >= ARRAY_SIZE(memory_type_name))
798 type_len = snprintf(pos, size, "[type=%u", md->type);
800 type_len = snprintf(pos, size, "[%-*s",
801 (int)(sizeof(memory_type_name[0]) - 1),
802 memory_type_name[md->type]);
803 if (type_len >= size)
809 attr = md->attribute;
810 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
811 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
812 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
814 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE))
815 snprintf(pos, size, "|attr=0x%016llx]",
816 (unsigned long long)attr);
819 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
820 attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
821 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "",
822 attr & EFI_MEMORY_NV ? "NV" : "",
823 attr & EFI_MEMORY_XP ? "XP" : "",
824 attr & EFI_MEMORY_RP ? "RP" : "",
825 attr & EFI_MEMORY_WP ? "WP" : "",
826 attr & EFI_MEMORY_RO ? "RO" : "",
827 attr & EFI_MEMORY_UCE ? "UCE" : "",
828 attr & EFI_MEMORY_WB ? "WB" : "",
829 attr & EFI_MEMORY_WT ? "WT" : "",
830 attr & EFI_MEMORY_WC ? "WC" : "",
831 attr & EFI_MEMORY_UC ? "UC" : "");
836 * IA64 has a funky EFI memory map that doesn't work the same way as
837 * other architectures.
841 * efi_mem_attributes - lookup memmap attributes for physical address
842 * @phys_addr: the physical address to lookup
844 * Search in the EFI memory map for the region covering
845 * @phys_addr. Returns the EFI memory attributes if the region
846 * was found in the memory map, 0 otherwise.
848 u64 efi_mem_attributes(unsigned long phys_addr)
850 efi_memory_desc_t *md;
852 if (!efi_enabled(EFI_MEMMAP))
855 for_each_efi_memory_desc(md) {
856 if ((md->phys_addr <= phys_addr) &&
857 (phys_addr < (md->phys_addr +
858 (md->num_pages << EFI_PAGE_SHIFT))))
859 return md->attribute;
865 * efi_mem_type - lookup memmap type for physical address
866 * @phys_addr: the physical address to lookup
868 * Search in the EFI memory map for the region covering @phys_addr.
869 * Returns the EFI memory type if the region was found in the memory
870 * map, EFI_RESERVED_TYPE (zero) otherwise.
872 int efi_mem_type(unsigned long phys_addr)
874 const efi_memory_desc_t *md;
876 if (!efi_enabled(EFI_MEMMAP))
879 for_each_efi_memory_desc(md) {
880 if ((md->phys_addr <= phys_addr) &&
881 (phys_addr < (md->phys_addr +
882 (md->num_pages << EFI_PAGE_SHIFT))))
889 int efi_status_to_err(efi_status_t status)
897 case EFI_INVALID_PARAMETER:
900 case EFI_OUT_OF_RESOURCES:
903 case EFI_DEVICE_ERROR:
906 case EFI_WRITE_PROTECTED:
909 case EFI_SECURITY_VIOLATION:
925 bool efi_is_table_address(unsigned long phys_addr)
929 if (phys_addr == EFI_INVALID_TABLE_ADDR)
932 for (i = 0; i < ARRAY_SIZE(efi_tables); i++)
933 if (*(efi_tables[i]) == phys_addr)
940 static int update_efi_random_seed(struct notifier_block *nb,
941 unsigned long code, void *unused)
943 struct linux_efi_random_seed *seed;
946 if (!kexec_in_progress)
949 seed = memremap(efi.rng_seed, sizeof(*seed), MEMREMAP_WB);
951 size = min(seed->size, EFI_RANDOM_SEED_SIZE);
954 pr_err("Could not map UEFI random seed!\n");
957 seed = memremap(efi.rng_seed, sizeof(*seed) + size,
961 get_random_bytes(seed->bits, seed->size);
964 pr_err("Could not map UEFI random seed!\n");
970 static struct notifier_block efi_random_seed_nb = {
971 .notifier_call = update_efi_random_seed,
974 static int register_update_efi_random_seed(void)
976 if (efi.rng_seed == EFI_INVALID_TABLE_ADDR)
978 return register_reboot_notifier(&efi_random_seed_nb);
980 late_initcall(register_update_efi_random_seed);