2 * Common EFI (Extensible Firmware Interface) support functions
3 * Based on Extensible Firmware Interface Specification version 1.0
5 * Copyright (C) 1999 VA Linux Systems
6 * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
7 * Copyright (C) 1999-2002 Hewlett-Packard Co.
8 * David Mosberger-Tang <davidm@hpl.hp.com>
9 * Stephane Eranian <eranian@hpl.hp.com>
10 * Copyright (C) 2005-2008 Intel Co.
11 * Fenghua Yu <fenghua.yu@intel.com>
12 * Bibo Mao <bibo.mao@intel.com>
13 * Chandramouli Narayanan <mouli@linux.intel.com>
14 * Huang Ying <ying.huang@intel.com>
16 * Copied from efi_32.c to eliminate the duplicated code between EFI
17 * 32/64 support code. --ying 2007-10-26
19 * All EFI Runtime Services are not implemented yet as EFI only
20 * supports physical mode addressing on SoftSDV. This is to be fixed
21 * in a future version. --drummond 1999-07-20
23 * Implemented EFI runtime services and virtual mode calls. --davidm
25 * Goutham Rao: <goutham.rao@intel.com>
26 * Skip non-WB memory and ignore empty memory ranges.
29 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
31 #include <linux/kernel.h>
32 #include <linux/init.h>
33 #include <linux/efi.h>
34 #include <linux/efi-bgrt.h>
35 #include <linux/export.h>
36 #include <linux/bootmem.h>
37 #include <linux/memblock.h>
38 #include <linux/spinlock.h>
39 #include <linux/uaccess.h>
40 #include <linux/time.h>
42 #include <linux/reboot.h>
43 #include <linux/bcd.h>
44 #include <linux/ucs2_string.h>
46 #include <asm/setup.h>
49 #include <asm/cacheflush.h>
50 #include <asm/tlbflush.h>
51 #include <asm/x86_init.h>
56 * There's some additional metadata associated with each
57 * variable. Intel's reference implementation is 60 bytes - bump that
58 * to account for potential alignment constraints
60 #define VAR_METADATA_SIZE 64
62 struct efi __read_mostly efi = {
63 .mps = EFI_INVALID_TABLE_ADDR,
64 .acpi = EFI_INVALID_TABLE_ADDR,
65 .acpi20 = EFI_INVALID_TABLE_ADDR,
66 .smbios = EFI_INVALID_TABLE_ADDR,
67 .sal_systab = EFI_INVALID_TABLE_ADDR,
68 .boot_info = EFI_INVALID_TABLE_ADDR,
69 .hcdp = EFI_INVALID_TABLE_ADDR,
70 .uga = EFI_INVALID_TABLE_ADDR,
71 .uv_systab = EFI_INVALID_TABLE_ADDR,
75 struct efi_memory_map memmap;
77 static struct efi efi_phys __initdata;
78 static efi_system_table_t efi_systab __initdata;
80 static u64 efi_var_store_size;
81 static u64 efi_var_remaining_size;
82 static u64 efi_var_max_var_size;
83 static u64 boot_used_size;
84 static u64 boot_var_size;
85 static u64 active_size;
87 unsigned long x86_efi_facility;
90 * Returns 1 if 'facility' is enabled, 0 otherwise.
92 int efi_enabled(int facility)
94 return test_bit(facility, &x86_efi_facility) != 0;
96 EXPORT_SYMBOL(efi_enabled);
98 static bool __initdata disable_runtime = false;
99 static int __init setup_noefi(char *arg)
101 disable_runtime = true;
104 early_param("noefi", setup_noefi);
107 EXPORT_SYMBOL(add_efi_memmap);
109 static int __init setup_add_efi_memmap(char *arg)
114 early_param("add_efi_memmap", setup_add_efi_memmap);
116 static bool efi_no_storage_paranoia;
118 static int __init setup_storage_paranoia(char *arg)
120 efi_no_storage_paranoia = true;
123 early_param("efi_no_storage_paranoia", setup_storage_paranoia);
126 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
131 spin_lock_irqsave(&rtc_lock, flags);
132 status = efi_call_virt2(get_time, tm, tc);
133 spin_unlock_irqrestore(&rtc_lock, flags);
137 static efi_status_t virt_efi_set_time(efi_time_t *tm)
142 spin_lock_irqsave(&rtc_lock, flags);
143 status = efi_call_virt1(set_time, tm);
144 spin_unlock_irqrestore(&rtc_lock, flags);
148 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
155 spin_lock_irqsave(&rtc_lock, flags);
156 status = efi_call_virt3(get_wakeup_time,
157 enabled, pending, tm);
158 spin_unlock_irqrestore(&rtc_lock, flags);
162 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
167 spin_lock_irqsave(&rtc_lock, flags);
168 status = efi_call_virt2(set_wakeup_time,
170 spin_unlock_irqrestore(&rtc_lock, flags);
174 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
177 unsigned long *data_size,
180 return efi_call_virt5(get_variable,
185 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
190 static bool finished = false;
193 status = efi_call_virt3(get_next_variable,
194 name_size, name, vendor);
196 if (status == EFI_NOT_FOUND) {
198 if (var_size < boot_used_size) {
199 boot_var_size = boot_used_size - var_size;
200 active_size += boot_var_size;
202 printk(KERN_WARNING FW_BUG "efi: Inconsistent initial sizes\n");
206 if (boot_used_size && !finished) {
212 s = virt_efi_get_variable(name, vendor, &attr, &size, NULL);
214 if (s != EFI_BUFFER_TOO_SMALL || !size)
217 tmp = kmalloc(size, GFP_ATOMIC);
222 s = virt_efi_get_variable(name, vendor, &attr, &size, tmp);
224 if (s == EFI_SUCCESS && (attr & EFI_VARIABLE_NON_VOLATILE)) {
226 var_size += ucs2_strsize(name, 1024);
228 active_size += VAR_METADATA_SIZE;
229 active_size += ucs2_strsize(name, 1024);
238 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
241 unsigned long data_size,
246 unsigned long orig_size = 0;
248 status = virt_efi_get_variable(name, vendor, &orig_attr, &orig_size,
251 if (status != EFI_BUFFER_TOO_SMALL)
254 status = efi_call_virt5(set_variable,
258 if (status == EFI_SUCCESS) {
260 active_size -= orig_size;
261 active_size -= ucs2_strsize(name, 1024);
262 active_size -= VAR_METADATA_SIZE;
265 active_size += data_size;
266 active_size += ucs2_strsize(name, 1024);
267 active_size += VAR_METADATA_SIZE;
274 static efi_status_t virt_efi_query_variable_info(u32 attr,
276 u64 *remaining_space,
277 u64 *max_variable_size)
279 if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
280 return EFI_UNSUPPORTED;
282 return efi_call_virt4(query_variable_info, attr, storage_space,
283 remaining_space, max_variable_size);
286 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
288 return efi_call_virt1(get_next_high_mono_count, count);
291 static void virt_efi_reset_system(int reset_type,
293 unsigned long data_size,
296 efi_call_virt4(reset_system, reset_type, status,
300 static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
302 unsigned long sg_list)
304 if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
305 return EFI_UNSUPPORTED;
307 return efi_call_virt3(update_capsule, capsules, count, sg_list);
310 static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
315 if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
316 return EFI_UNSUPPORTED;
318 return efi_call_virt4(query_capsule_caps, capsules, count, max_size,
322 static efi_status_t __init phys_efi_set_virtual_address_map(
323 unsigned long memory_map_size,
324 unsigned long descriptor_size,
325 u32 descriptor_version,
326 efi_memory_desc_t *virtual_map)
330 efi_call_phys_prelog();
331 status = efi_call_phys4(efi_phys.set_virtual_address_map,
332 memory_map_size, descriptor_size,
333 descriptor_version, virtual_map);
334 efi_call_phys_epilog();
338 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
344 spin_lock_irqsave(&rtc_lock, flags);
345 efi_call_phys_prelog();
346 status = efi_call_phys2(efi_phys.get_time, virt_to_phys(tm),
348 efi_call_phys_epilog();
349 spin_unlock_irqrestore(&rtc_lock, flags);
353 int efi_set_rtc_mmss(unsigned long nowtime)
355 int real_seconds, real_minutes;
360 status = efi.get_time(&eft, &cap);
361 if (status != EFI_SUCCESS) {
362 pr_err("Oops: efitime: can't read time!\n");
366 real_seconds = nowtime % 60;
367 real_minutes = nowtime / 60;
368 if (((abs(real_minutes - eft.minute) + 15)/30) & 1)
371 eft.minute = real_minutes;
372 eft.second = real_seconds;
374 status = efi.set_time(&eft);
375 if (status != EFI_SUCCESS) {
376 pr_err("Oops: efitime: can't write time!\n");
382 unsigned long efi_get_time(void)
388 status = efi.get_time(&eft, &cap);
389 if (status != EFI_SUCCESS)
390 pr_err("Oops: efitime: can't read time!\n");
392 return mktime(eft.year, eft.month, eft.day, eft.hour,
393 eft.minute, eft.second);
397 * Tell the kernel about the EFI memory map. This might include
398 * more than the max 128 entries that can fit in the e820 legacy
399 * (zeropage) memory map.
402 static void __init do_add_efi_memmap(void)
406 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
407 efi_memory_desc_t *md = p;
408 unsigned long long start = md->phys_addr;
409 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
413 case EFI_LOADER_CODE:
414 case EFI_LOADER_DATA:
415 case EFI_BOOT_SERVICES_CODE:
416 case EFI_BOOT_SERVICES_DATA:
417 case EFI_CONVENTIONAL_MEMORY:
418 if (md->attribute & EFI_MEMORY_WB)
419 e820_type = E820_RAM;
421 e820_type = E820_RESERVED;
423 case EFI_ACPI_RECLAIM_MEMORY:
424 e820_type = E820_ACPI;
426 case EFI_ACPI_MEMORY_NVS:
427 e820_type = E820_NVS;
429 case EFI_UNUSABLE_MEMORY:
430 e820_type = E820_UNUSABLE;
434 * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
435 * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
436 * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
438 e820_type = E820_RESERVED;
441 e820_add_region(start, size, e820_type);
443 sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
446 int __init efi_memblock_x86_reserve_range(void)
448 struct efi_info *e = &boot_params.efi_info;
452 /* Can't handle data above 4GB at this time */
453 if (e->efi_memmap_hi) {
454 pr_err("Memory map is above 4GB, disabling EFI.\n");
457 pmap = e->efi_memmap;
459 pmap = (e->efi_memmap | ((__u64)e->efi_memmap_hi << 32));
461 memmap.phys_map = (void *)pmap;
462 memmap.nr_map = e->efi_memmap_size /
464 memmap.desc_size = e->efi_memdesc_size;
465 memmap.desc_version = e->efi_memdesc_version;
467 memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
473 static void __init print_efi_memmap(void)
475 efi_memory_desc_t *md;
479 for (p = memmap.map, i = 0;
481 p += memmap.desc_size, i++) {
483 pr_info("mem%02u: type=%u, attr=0x%llx, "
484 "range=[0x%016llx-0x%016llx) (%lluMB)\n",
485 i, md->type, md->attribute, md->phys_addr,
486 md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
487 (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
490 #endif /* EFI_DEBUG */
492 void __init efi_reserve_boot_services(void)
496 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
497 efi_memory_desc_t *md = p;
498 u64 start = md->phys_addr;
499 u64 size = md->num_pages << EFI_PAGE_SHIFT;
501 if (md->type != EFI_BOOT_SERVICES_CODE &&
502 md->type != EFI_BOOT_SERVICES_DATA)
504 /* Only reserve where possible:
505 * - Not within any already allocated areas
506 * - Not over any memory area (really needed, if above?)
507 * - Not within any part of the kernel
508 * - Not the bios reserved area
510 if ((start+size >= __pa_symbol(_text)
511 && start <= __pa_symbol(_end)) ||
512 !e820_all_mapped(start, start+size, E820_RAM) ||
513 memblock_is_region_reserved(start, size)) {
514 /* Could not reserve, skip it */
516 memblock_dbg("Could not reserve boot range "
517 "[0x%010llx-0x%010llx]\n",
518 start, start+size-1);
520 memblock_reserve(start, size);
524 void __init efi_unmap_memmap(void)
526 clear_bit(EFI_MEMMAP, &x86_efi_facility);
528 early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
533 void __init efi_free_boot_services(void)
537 if (!efi_is_native())
540 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
541 efi_memory_desc_t *md = p;
542 unsigned long long start = md->phys_addr;
543 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
545 if (md->type != EFI_BOOT_SERVICES_CODE &&
546 md->type != EFI_BOOT_SERVICES_DATA)
549 /* Could not reserve boot area */
553 free_bootmem_late(start, size);
559 static int __init efi_systab_init(void *phys)
561 if (efi_enabled(EFI_64BIT)) {
562 efi_system_table_64_t *systab64;
565 systab64 = early_ioremap((unsigned long)phys,
567 if (systab64 == NULL) {
568 pr_err("Couldn't map the system table!\n");
572 efi_systab.hdr = systab64->hdr;
573 efi_systab.fw_vendor = systab64->fw_vendor;
574 tmp |= systab64->fw_vendor;
575 efi_systab.fw_revision = systab64->fw_revision;
576 efi_systab.con_in_handle = systab64->con_in_handle;
577 tmp |= systab64->con_in_handle;
578 efi_systab.con_in = systab64->con_in;
579 tmp |= systab64->con_in;
580 efi_systab.con_out_handle = systab64->con_out_handle;
581 tmp |= systab64->con_out_handle;
582 efi_systab.con_out = systab64->con_out;
583 tmp |= systab64->con_out;
584 efi_systab.stderr_handle = systab64->stderr_handle;
585 tmp |= systab64->stderr_handle;
586 efi_systab.stderr = systab64->stderr;
587 tmp |= systab64->stderr;
588 efi_systab.runtime = (void *)(unsigned long)systab64->runtime;
589 tmp |= systab64->runtime;
590 efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
591 tmp |= systab64->boottime;
592 efi_systab.nr_tables = systab64->nr_tables;
593 efi_systab.tables = systab64->tables;
594 tmp |= systab64->tables;
596 early_iounmap(systab64, sizeof(*systab64));
599 pr_err("EFI data located above 4GB, disabling EFI.\n");
604 efi_system_table_32_t *systab32;
606 systab32 = early_ioremap((unsigned long)phys,
608 if (systab32 == NULL) {
609 pr_err("Couldn't map the system table!\n");
613 efi_systab.hdr = systab32->hdr;
614 efi_systab.fw_vendor = systab32->fw_vendor;
615 efi_systab.fw_revision = systab32->fw_revision;
616 efi_systab.con_in_handle = systab32->con_in_handle;
617 efi_systab.con_in = systab32->con_in;
618 efi_systab.con_out_handle = systab32->con_out_handle;
619 efi_systab.con_out = systab32->con_out;
620 efi_systab.stderr_handle = systab32->stderr_handle;
621 efi_systab.stderr = systab32->stderr;
622 efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
623 efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
624 efi_systab.nr_tables = systab32->nr_tables;
625 efi_systab.tables = systab32->tables;
627 early_iounmap(systab32, sizeof(*systab32));
630 efi.systab = &efi_systab;
633 * Verify the EFI Table
635 if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
636 pr_err("System table signature incorrect!\n");
639 if ((efi.systab->hdr.revision >> 16) == 0)
640 pr_err("Warning: System table version "
641 "%d.%02d, expected 1.00 or greater!\n",
642 efi.systab->hdr.revision >> 16,
643 efi.systab->hdr.revision & 0xffff);
648 static int __init efi_config_init(u64 tables, int nr_tables)
650 void *config_tables, *tablep;
653 if (efi_enabled(EFI_64BIT))
654 sz = sizeof(efi_config_table_64_t);
656 sz = sizeof(efi_config_table_32_t);
659 * Let's see what config tables the firmware passed to us.
661 config_tables = early_ioremap(tables, nr_tables * sz);
662 if (config_tables == NULL) {
663 pr_err("Could not map Configuration table!\n");
667 tablep = config_tables;
669 for (i = 0; i < efi.systab->nr_tables; i++) {
673 if (efi_enabled(EFI_64BIT)) {
675 guid = ((efi_config_table_64_t *)tablep)->guid;
676 table64 = ((efi_config_table_64_t *)tablep)->table;
681 pr_err("Table located above 4GB, disabling EFI.\n");
682 early_iounmap(config_tables,
683 efi.systab->nr_tables * sz);
688 guid = ((efi_config_table_32_t *)tablep)->guid;
689 table = ((efi_config_table_32_t *)tablep)->table;
691 if (!efi_guidcmp(guid, MPS_TABLE_GUID)) {
693 pr_cont(" MPS=0x%lx ", table);
694 } else if (!efi_guidcmp(guid, ACPI_20_TABLE_GUID)) {
696 pr_cont(" ACPI 2.0=0x%lx ", table);
697 } else if (!efi_guidcmp(guid, ACPI_TABLE_GUID)) {
699 pr_cont(" ACPI=0x%lx ", table);
700 } else if (!efi_guidcmp(guid, SMBIOS_TABLE_GUID)) {
702 pr_cont(" SMBIOS=0x%lx ", table);
704 } else if (!efi_guidcmp(guid, UV_SYSTEM_TABLE_GUID)) {
705 efi.uv_systab = table;
706 pr_cont(" UVsystab=0x%lx ", table);
708 } else if (!efi_guidcmp(guid, HCDP_TABLE_GUID)) {
710 pr_cont(" HCDP=0x%lx ", table);
711 } else if (!efi_guidcmp(guid, UGA_IO_PROTOCOL_GUID)) {
713 pr_cont(" UGA=0x%lx ", table);
718 early_iounmap(config_tables, efi.systab->nr_tables * sz);
722 static int __init efi_runtime_init(void)
724 efi_runtime_services_t *runtime;
727 * Check out the runtime services table. We need to map
728 * the runtime services table so that we can grab the physical
729 * address of several of the EFI runtime functions, needed to
730 * set the firmware into virtual mode.
732 runtime = early_ioremap((unsigned long)efi.systab->runtime,
733 sizeof(efi_runtime_services_t));
735 pr_err("Could not map the runtime service table!\n");
739 * We will only need *early* access to the following
740 * two EFI runtime services before set_virtual_address_map
743 efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
744 efi_phys.set_virtual_address_map =
745 (efi_set_virtual_address_map_t *)
746 runtime->set_virtual_address_map;
748 * Make efi_get_time can be called before entering
751 efi.get_time = phys_efi_get_time;
752 early_iounmap(runtime, sizeof(efi_runtime_services_t));
757 static int __init efi_memmap_init(void)
759 /* Map the EFI memory map */
760 memmap.map = early_ioremap((unsigned long)memmap.phys_map,
761 memmap.nr_map * memmap.desc_size);
762 if (memmap.map == NULL) {
763 pr_err("Could not map the memory map!\n");
766 memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
774 void __init efi_init(void)
777 char vendor[100] = "unknown";
780 struct setup_data *data;
781 struct efi_var_bootdata *efi_var_data;
785 if (boot_params.efi_info.efi_systab_hi ||
786 boot_params.efi_info.efi_memmap_hi) {
787 pr_info("Table located above 4GB, disabling EFI.\n");
790 efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
792 efi_phys.systab = (efi_system_table_t *)
793 (boot_params.efi_info.efi_systab |
794 ((__u64)boot_params.efi_info.efi_systab_hi<<32));
797 if (efi_systab_init(efi_phys.systab))
800 pa_data = boot_params.hdr.setup_data;
802 data = early_ioremap(pa_data, sizeof(*efi_var_data));
803 if (data->type == SETUP_EFI_VARS) {
804 efi_var_data = (struct efi_var_bootdata *)data;
806 efi_var_store_size = efi_var_data->store_size;
807 efi_var_remaining_size = efi_var_data->remaining_size;
808 efi_var_max_var_size = efi_var_data->max_var_size;
810 pa_data = data->next;
811 early_iounmap(data, sizeof(*efi_var_data));
814 boot_used_size = efi_var_store_size - efi_var_remaining_size;
816 set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
819 * Show what we know for posterity
821 c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
823 for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
827 pr_err("Could not map the firmware vendor!\n");
828 early_iounmap(tmp, 2);
830 pr_info("EFI v%u.%.02u by %s\n",
831 efi.systab->hdr.revision >> 16,
832 efi.systab->hdr.revision & 0xffff, vendor);
834 if (efi_config_init(efi.systab->tables, efi.systab->nr_tables))
837 set_bit(EFI_CONFIG_TABLES, &x86_efi_facility);
840 * Note: We currently don't support runtime services on an EFI
841 * that doesn't match the kernel 32/64-bit mode.
844 if (!efi_is_native())
845 pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
847 if (disable_runtime || efi_runtime_init())
849 set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
852 if (efi_memmap_init())
855 set_bit(EFI_MEMMAP, &x86_efi_facility);
858 if (efi_is_native()) {
859 x86_platform.get_wallclock = efi_get_time;
860 x86_platform.set_wallclock = efi_set_rtc_mmss;
869 void __init efi_late_init(void)
874 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
878 addr = md->virt_addr;
879 npages = md->num_pages;
881 memrange_efi_to_native(&addr, &npages);
884 set_memory_x(addr, npages);
886 set_memory_nx(addr, npages);
889 static void __init runtime_code_page_mkexec(void)
891 efi_memory_desc_t *md;
894 /* Make EFI runtime service code area executable */
895 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
898 if (md->type != EFI_RUNTIME_SERVICES_CODE)
901 efi_set_executable(md, true);
906 * We can't ioremap data in EFI boot services RAM, because we've already mapped
907 * it as RAM. So, look it up in the existing EFI memory map instead. Only
908 * callable after efi_enter_virtual_mode and before efi_free_boot_services.
910 void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
913 if (WARN_ON(!memmap.map))
915 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
916 efi_memory_desc_t *md = p;
917 u64 size = md->num_pages << EFI_PAGE_SHIFT;
918 u64 end = md->phys_addr + size;
919 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
920 md->type != EFI_BOOT_SERVICES_CODE &&
921 md->type != EFI_BOOT_SERVICES_DATA)
925 if (phys_addr >= md->phys_addr && phys_addr < end) {
926 phys_addr += md->virt_addr - md->phys_addr;
927 return (__force void __iomem *)(unsigned long)phys_addr;
933 void efi_memory_uc(u64 addr, unsigned long size)
935 unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
938 npages = round_up(size, page_shift) / page_shift;
939 memrange_efi_to_native(&addr, &npages);
940 set_memory_uc(addr, npages);
944 * This function will switch the EFI runtime services to virtual mode.
945 * Essentially, look through the EFI memmap and map every region that
946 * has the runtime attribute bit set in its memory descriptor and update
947 * that memory descriptor with the virtual address obtained from ioremap().
948 * This enables the runtime services to be called without having to
949 * thunk back into physical mode for every invocation.
951 void __init efi_enter_virtual_mode(void)
953 efi_memory_desc_t *md, *prev_md = NULL;
956 u64 end, systab, start_pfn, end_pfn;
957 void *p, *va, *new_memmap = NULL;
963 * We don't do virtual mode, since we don't do runtime services, on
967 if (!efi_is_native()) {
972 /* Merge contiguous regions of the same type and attribute */
973 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
982 if (prev_md->type != md->type ||
983 prev_md->attribute != md->attribute) {
988 prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
990 if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
991 prev_md->num_pages += md->num_pages;
992 md->type = EFI_RESERVED_TYPE;
999 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1001 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
1002 md->type != EFI_BOOT_SERVICES_CODE &&
1003 md->type != EFI_BOOT_SERVICES_DATA)
1006 size = md->num_pages << EFI_PAGE_SHIFT;
1007 end = md->phys_addr + size;
1009 start_pfn = PFN_DOWN(md->phys_addr);
1010 end_pfn = PFN_UP(end);
1011 if (pfn_range_is_mapped(start_pfn, end_pfn)) {
1012 va = __va(md->phys_addr);
1014 if (!(md->attribute & EFI_MEMORY_WB))
1015 efi_memory_uc((u64)(unsigned long)va, size);
1017 va = efi_ioremap(md->phys_addr, size,
1018 md->type, md->attribute);
1020 md->virt_addr = (u64) (unsigned long) va;
1023 pr_err("ioremap of 0x%llX failed!\n",
1024 (unsigned long long)md->phys_addr);
1028 systab = (u64) (unsigned long) efi_phys.systab;
1029 if (md->phys_addr <= systab && systab < end) {
1030 systab += md->virt_addr - md->phys_addr;
1031 efi.systab = (efi_system_table_t *) (unsigned long) systab;
1033 new_memmap = krealloc(new_memmap,
1034 (count + 1) * memmap.desc_size,
1036 memcpy(new_memmap + (count * memmap.desc_size), md,
1041 BUG_ON(!efi.systab);
1043 status = phys_efi_set_virtual_address_map(
1044 memmap.desc_size * count,
1046 memmap.desc_version,
1047 (efi_memory_desc_t *)__pa(new_memmap));
1049 if (status != EFI_SUCCESS) {
1050 pr_alert("Unable to switch EFI into virtual mode "
1051 "(status=%lx)!\n", status);
1052 panic("EFI call to SetVirtualAddressMap() failed!");
1056 * Now that EFI is in virtual mode, update the function
1057 * pointers in the runtime service table to the new virtual addresses.
1059 * Call EFI services through wrapper functions.
1061 efi.runtime_version = efi_systab.hdr.revision;
1062 efi.get_time = virt_efi_get_time;
1063 efi.set_time = virt_efi_set_time;
1064 efi.get_wakeup_time = virt_efi_get_wakeup_time;
1065 efi.set_wakeup_time = virt_efi_set_wakeup_time;
1066 efi.get_variable = virt_efi_get_variable;
1067 efi.get_next_variable = virt_efi_get_next_variable;
1068 efi.set_variable = virt_efi_set_variable;
1069 efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
1070 efi.reset_system = virt_efi_reset_system;
1071 efi.set_virtual_address_map = NULL;
1072 efi.query_variable_info = virt_efi_query_variable_info;
1073 efi.update_capsule = virt_efi_update_capsule;
1074 efi.query_capsule_caps = virt_efi_query_capsule_caps;
1075 if (__supported_pte_mask & _PAGE_NX)
1076 runtime_code_page_mkexec();
1082 * Convenience functions to obtain memory types and attributes
1084 u32 efi_mem_type(unsigned long phys_addr)
1086 efi_memory_desc_t *md;
1089 if (!efi_enabled(EFI_MEMMAP))
1092 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1094 if ((md->phys_addr <= phys_addr) &&
1095 (phys_addr < (md->phys_addr +
1096 (md->num_pages << EFI_PAGE_SHIFT))))
1102 u64 efi_mem_attributes(unsigned long phys_addr)
1104 efi_memory_desc_t *md;
1107 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1109 if ((md->phys_addr <= phys_addr) &&
1110 (phys_addr < (md->phys_addr +
1111 (md->num_pages << EFI_PAGE_SHIFT))))
1112 return md->attribute;
1118 * Some firmware has serious problems when using more than 50% of the EFI
1119 * variable store, i.e. it triggers bugs that can brick machines. Ensure that
1120 * we never use more than this safe limit.
1122 * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
1125 efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
1127 efi_status_t status;
1128 u64 storage_size, remaining_size, max_size;
1130 status = efi.query_variable_info(attributes, &storage_size,
1131 &remaining_size, &max_size);
1132 if (status != EFI_SUCCESS)
1135 if (!max_size && remaining_size > size)
1136 printk_once(KERN_ERR FW_BUG "Broken EFI implementation"
1137 " is returning MaxVariableSize=0\n");
1139 * Some firmware implementations refuse to boot if there's insufficient
1140 * space in the variable store. We account for that by refusing the
1141 * write if permitting it would reduce the available space to under
1142 * 50%. However, some firmware won't reclaim variable space until
1143 * after the used (not merely the actively used) space drops below
1144 * a threshold. We can approximate that case with the value calculated
1145 * above. If both the firmware and our calculations indicate that the
1146 * available space would drop below 50%, refuse the write.
1149 if (!storage_size || size > remaining_size ||
1150 (max_size && size > max_size))
1151 return EFI_OUT_OF_RESOURCES;
1153 if (!efi_no_storage_paranoia &&
1154 ((active_size + size + VAR_METADATA_SIZE > storage_size / 2) &&
1155 (remaining_size - size < storage_size / 2)))
1156 return EFI_OUT_OF_RESOURCES;
1160 EXPORT_SYMBOL_GPL(efi_query_variable_store);