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/slab.h>
38 #include <linux/memblock.h>
39 #include <linux/spinlock.h>
40 #include <linux/uaccess.h>
41 #include <linux/time.h>
43 #include <linux/reboot.h>
44 #include <linux/bcd.h>
46 #include <asm/setup.h>
49 #include <asm/cacheflush.h>
50 #include <asm/tlbflush.h>
51 #include <asm/x86_init.h>
56 #define EFI_MIN_RESERVE 5120
58 #define EFI_DUMMY_GUID \
59 EFI_GUID(0x4424ac57, 0xbe4b, 0x47dd, 0x9e, 0x97, 0xed, 0x50, 0xf0, 0x9f, 0x92, 0xa9)
61 static efi_char16_t efi_dummy_name[6] = { 'D', 'U', 'M', 'M', 'Y', 0 };
63 struct efi __read_mostly efi = {
64 .mps = EFI_INVALID_TABLE_ADDR,
65 .acpi = EFI_INVALID_TABLE_ADDR,
66 .acpi20 = EFI_INVALID_TABLE_ADDR,
67 .smbios = EFI_INVALID_TABLE_ADDR,
68 .sal_systab = EFI_INVALID_TABLE_ADDR,
69 .boot_info = EFI_INVALID_TABLE_ADDR,
70 .hcdp = EFI_INVALID_TABLE_ADDR,
71 .uga = EFI_INVALID_TABLE_ADDR,
72 .uv_systab = EFI_INVALID_TABLE_ADDR,
76 struct efi_memory_map memmap;
78 static struct efi efi_phys __initdata;
79 static efi_system_table_t efi_systab __initdata;
81 unsigned long x86_efi_facility;
84 * Returns 1 if 'facility' is enabled, 0 otherwise.
86 int efi_enabled(int facility)
88 return test_bit(facility, &x86_efi_facility) != 0;
90 EXPORT_SYMBOL(efi_enabled);
92 static bool __initdata disable_runtime = false;
93 static int __init setup_noefi(char *arg)
95 disable_runtime = true;
98 early_param("noefi", setup_noefi);
101 EXPORT_SYMBOL(add_efi_memmap);
103 static int __init setup_add_efi_memmap(char *arg)
108 early_param("add_efi_memmap", setup_add_efi_memmap);
110 static bool efi_no_storage_paranoia;
112 static int __init setup_storage_paranoia(char *arg)
114 efi_no_storage_paranoia = true;
117 early_param("efi_no_storage_paranoia", setup_storage_paranoia);
120 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
125 spin_lock_irqsave(&rtc_lock, flags);
126 status = efi_call_virt2(get_time, tm, tc);
127 spin_unlock_irqrestore(&rtc_lock, flags);
131 static efi_status_t virt_efi_set_time(efi_time_t *tm)
136 spin_lock_irqsave(&rtc_lock, flags);
137 status = efi_call_virt1(set_time, tm);
138 spin_unlock_irqrestore(&rtc_lock, flags);
142 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
149 spin_lock_irqsave(&rtc_lock, flags);
150 status = efi_call_virt3(get_wakeup_time,
151 enabled, pending, tm);
152 spin_unlock_irqrestore(&rtc_lock, flags);
156 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
161 spin_lock_irqsave(&rtc_lock, flags);
162 status = efi_call_virt2(set_wakeup_time,
164 spin_unlock_irqrestore(&rtc_lock, flags);
168 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
171 unsigned long *data_size,
174 return efi_call_virt5(get_variable,
179 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
183 return efi_call_virt3(get_next_variable,
184 name_size, name, vendor);
187 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
190 unsigned long data_size,
193 return efi_call_virt5(set_variable,
198 static efi_status_t virt_efi_query_variable_info(u32 attr,
200 u64 *remaining_space,
201 u64 *max_variable_size)
203 if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
204 return EFI_UNSUPPORTED;
206 return efi_call_virt4(query_variable_info, attr, storage_space,
207 remaining_space, max_variable_size);
210 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
212 return efi_call_virt1(get_next_high_mono_count, count);
215 static void virt_efi_reset_system(int reset_type,
217 unsigned long data_size,
220 efi_call_virt4(reset_system, reset_type, status,
224 static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
226 unsigned long sg_list)
228 if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
229 return EFI_UNSUPPORTED;
231 return efi_call_virt3(update_capsule, capsules, count, sg_list);
234 static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
239 if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
240 return EFI_UNSUPPORTED;
242 return efi_call_virt4(query_capsule_caps, capsules, count, max_size,
246 static efi_status_t __init phys_efi_set_virtual_address_map(
247 unsigned long memory_map_size,
248 unsigned long descriptor_size,
249 u32 descriptor_version,
250 efi_memory_desc_t *virtual_map)
254 efi_call_phys_prelog();
255 status = efi_call_phys4(efi_phys.set_virtual_address_map,
256 memory_map_size, descriptor_size,
257 descriptor_version, virtual_map);
258 efi_call_phys_epilog();
262 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
268 spin_lock_irqsave(&rtc_lock, flags);
269 efi_call_phys_prelog();
270 status = efi_call_phys2(efi_phys.get_time, virt_to_phys(tm),
272 efi_call_phys_epilog();
273 spin_unlock_irqrestore(&rtc_lock, flags);
277 int efi_set_rtc_mmss(unsigned long nowtime)
284 status = efi.get_time(&eft, &cap);
285 if (status != EFI_SUCCESS) {
286 pr_err("Oops: efitime: can't read time!\n");
290 rtc_time_to_tm(nowtime, &tm);
291 if (!rtc_valid_tm(&tm)) {
292 eft.year = tm.tm_year + 1900;
293 eft.month = tm.tm_mon + 1;
294 eft.day = tm.tm_mday;
295 eft.minute = tm.tm_min;
296 eft.second = tm.tm_sec;
300 "%s: Invalid EFI RTC value: write of %lx to EFI RTC failed\n",
301 __FUNCTION__, nowtime);
305 status = efi.set_time(&eft);
306 if (status != EFI_SUCCESS) {
307 pr_err("Oops: efitime: can't write time!\n");
313 unsigned long efi_get_time(void)
319 status = efi.get_time(&eft, &cap);
320 if (status != EFI_SUCCESS)
321 pr_err("Oops: efitime: can't read time!\n");
323 return mktime(eft.year, eft.month, eft.day, eft.hour,
324 eft.minute, eft.second);
328 * Tell the kernel about the EFI memory map. This might include
329 * more than the max 128 entries that can fit in the e820 legacy
330 * (zeropage) memory map.
333 static void __init do_add_efi_memmap(void)
337 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
338 efi_memory_desc_t *md = p;
339 unsigned long long start = md->phys_addr;
340 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
344 case EFI_LOADER_CODE:
345 case EFI_LOADER_DATA:
346 case EFI_BOOT_SERVICES_CODE:
347 case EFI_BOOT_SERVICES_DATA:
348 case EFI_CONVENTIONAL_MEMORY:
349 if (md->attribute & EFI_MEMORY_WB)
350 e820_type = E820_RAM;
352 e820_type = E820_RESERVED;
354 case EFI_ACPI_RECLAIM_MEMORY:
355 e820_type = E820_ACPI;
357 case EFI_ACPI_MEMORY_NVS:
358 e820_type = E820_NVS;
360 case EFI_UNUSABLE_MEMORY:
361 e820_type = E820_UNUSABLE;
365 * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
366 * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
367 * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
369 e820_type = E820_RESERVED;
372 e820_add_region(start, size, e820_type);
374 sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
377 int __init efi_memblock_x86_reserve_range(void)
379 struct efi_info *e = &boot_params.efi_info;
383 /* Can't handle data above 4GB at this time */
384 if (e->efi_memmap_hi) {
385 pr_err("Memory map is above 4GB, disabling EFI.\n");
388 pmap = e->efi_memmap;
390 pmap = (e->efi_memmap | ((__u64)e->efi_memmap_hi << 32));
392 memmap.phys_map = (void *)pmap;
393 memmap.nr_map = e->efi_memmap_size /
395 memmap.desc_size = e->efi_memdesc_size;
396 memmap.desc_version = e->efi_memdesc_version;
398 memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
404 static void __init print_efi_memmap(void)
406 efi_memory_desc_t *md;
410 for (p = memmap.map, i = 0;
412 p += memmap.desc_size, i++) {
414 pr_info("mem%02u: type=%u, attr=0x%llx, "
415 "range=[0x%016llx-0x%016llx) (%lluMB)\n",
416 i, md->type, md->attribute, md->phys_addr,
417 md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
418 (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
421 #endif /* EFI_DEBUG */
423 void __init efi_reserve_boot_services(void)
427 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
428 efi_memory_desc_t *md = p;
429 u64 start = md->phys_addr;
430 u64 size = md->num_pages << EFI_PAGE_SHIFT;
432 if (md->type != EFI_BOOT_SERVICES_CODE &&
433 md->type != EFI_BOOT_SERVICES_DATA)
435 /* Only reserve where possible:
436 * - Not within any already allocated areas
437 * - Not over any memory area (really needed, if above?)
438 * - Not within any part of the kernel
439 * - Not the bios reserved area
441 if ((start+size >= __pa_symbol(_text)
442 && start <= __pa_symbol(_end)) ||
443 !e820_all_mapped(start, start+size, E820_RAM) ||
444 memblock_is_region_reserved(start, size)) {
445 /* Could not reserve, skip it */
447 memblock_dbg("Could not reserve boot range "
448 "[0x%010llx-0x%010llx]\n",
449 start, start+size-1);
451 memblock_reserve(start, size);
455 void __init efi_unmap_memmap(void)
457 clear_bit(EFI_MEMMAP, &x86_efi_facility);
459 early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
464 void __init efi_free_boot_services(void)
468 if (!efi_is_native())
471 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
472 efi_memory_desc_t *md = p;
473 unsigned long long start = md->phys_addr;
474 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
476 if (md->type != EFI_BOOT_SERVICES_CODE &&
477 md->type != EFI_BOOT_SERVICES_DATA)
480 /* Could not reserve boot area */
484 free_bootmem_late(start, size);
490 static int __init efi_systab_init(void *phys)
492 if (efi_enabled(EFI_64BIT)) {
493 efi_system_table_64_t *systab64;
496 systab64 = early_ioremap((unsigned long)phys,
498 if (systab64 == NULL) {
499 pr_err("Couldn't map the system table!\n");
503 efi_systab.hdr = systab64->hdr;
504 efi_systab.fw_vendor = systab64->fw_vendor;
505 tmp |= systab64->fw_vendor;
506 efi_systab.fw_revision = systab64->fw_revision;
507 efi_systab.con_in_handle = systab64->con_in_handle;
508 tmp |= systab64->con_in_handle;
509 efi_systab.con_in = systab64->con_in;
510 tmp |= systab64->con_in;
511 efi_systab.con_out_handle = systab64->con_out_handle;
512 tmp |= systab64->con_out_handle;
513 efi_systab.con_out = systab64->con_out;
514 tmp |= systab64->con_out;
515 efi_systab.stderr_handle = systab64->stderr_handle;
516 tmp |= systab64->stderr_handle;
517 efi_systab.stderr = systab64->stderr;
518 tmp |= systab64->stderr;
519 efi_systab.runtime = (void *)(unsigned long)systab64->runtime;
520 tmp |= systab64->runtime;
521 efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
522 tmp |= systab64->boottime;
523 efi_systab.nr_tables = systab64->nr_tables;
524 efi_systab.tables = systab64->tables;
525 tmp |= systab64->tables;
527 early_iounmap(systab64, sizeof(*systab64));
530 pr_err("EFI data located above 4GB, disabling EFI.\n");
535 efi_system_table_32_t *systab32;
537 systab32 = early_ioremap((unsigned long)phys,
539 if (systab32 == NULL) {
540 pr_err("Couldn't map the system table!\n");
544 efi_systab.hdr = systab32->hdr;
545 efi_systab.fw_vendor = systab32->fw_vendor;
546 efi_systab.fw_revision = systab32->fw_revision;
547 efi_systab.con_in_handle = systab32->con_in_handle;
548 efi_systab.con_in = systab32->con_in;
549 efi_systab.con_out_handle = systab32->con_out_handle;
550 efi_systab.con_out = systab32->con_out;
551 efi_systab.stderr_handle = systab32->stderr_handle;
552 efi_systab.stderr = systab32->stderr;
553 efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
554 efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
555 efi_systab.nr_tables = systab32->nr_tables;
556 efi_systab.tables = systab32->tables;
558 early_iounmap(systab32, sizeof(*systab32));
561 efi.systab = &efi_systab;
564 * Verify the EFI Table
566 if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
567 pr_err("System table signature incorrect!\n");
570 if ((efi.systab->hdr.revision >> 16) == 0)
571 pr_err("Warning: System table version "
572 "%d.%02d, expected 1.00 or greater!\n",
573 efi.systab->hdr.revision >> 16,
574 efi.systab->hdr.revision & 0xffff);
579 static int __init efi_config_init(u64 tables, int nr_tables)
581 void *config_tables, *tablep;
584 if (efi_enabled(EFI_64BIT))
585 sz = sizeof(efi_config_table_64_t);
587 sz = sizeof(efi_config_table_32_t);
590 * Let's see what config tables the firmware passed to us.
592 config_tables = early_ioremap(tables, nr_tables * sz);
593 if (config_tables == NULL) {
594 pr_err("Could not map Configuration table!\n");
598 tablep = config_tables;
600 for (i = 0; i < efi.systab->nr_tables; i++) {
604 if (efi_enabled(EFI_64BIT)) {
606 guid = ((efi_config_table_64_t *)tablep)->guid;
607 table64 = ((efi_config_table_64_t *)tablep)->table;
612 pr_err("Table located above 4GB, disabling EFI.\n");
613 early_iounmap(config_tables,
614 efi.systab->nr_tables * sz);
619 guid = ((efi_config_table_32_t *)tablep)->guid;
620 table = ((efi_config_table_32_t *)tablep)->table;
622 if (!efi_guidcmp(guid, MPS_TABLE_GUID)) {
624 pr_cont(" MPS=0x%lx ", table);
625 } else if (!efi_guidcmp(guid, ACPI_20_TABLE_GUID)) {
627 pr_cont(" ACPI 2.0=0x%lx ", table);
628 } else if (!efi_guidcmp(guid, ACPI_TABLE_GUID)) {
630 pr_cont(" ACPI=0x%lx ", table);
631 } else if (!efi_guidcmp(guid, SMBIOS_TABLE_GUID)) {
633 pr_cont(" SMBIOS=0x%lx ", table);
635 } else if (!efi_guidcmp(guid, UV_SYSTEM_TABLE_GUID)) {
636 efi.uv_systab = table;
637 pr_cont(" UVsystab=0x%lx ", table);
639 } else if (!efi_guidcmp(guid, HCDP_TABLE_GUID)) {
641 pr_cont(" HCDP=0x%lx ", table);
642 } else if (!efi_guidcmp(guid, UGA_IO_PROTOCOL_GUID)) {
644 pr_cont(" UGA=0x%lx ", table);
649 early_iounmap(config_tables, efi.systab->nr_tables * sz);
653 static int __init efi_runtime_init(void)
655 efi_runtime_services_t *runtime;
658 * Check out the runtime services table. We need to map
659 * the runtime services table so that we can grab the physical
660 * address of several of the EFI runtime functions, needed to
661 * set the firmware into virtual mode.
663 runtime = early_ioremap((unsigned long)efi.systab->runtime,
664 sizeof(efi_runtime_services_t));
666 pr_err("Could not map the runtime service table!\n");
670 * We will only need *early* access to the following
671 * two EFI runtime services before set_virtual_address_map
674 efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
675 efi_phys.set_virtual_address_map =
676 (efi_set_virtual_address_map_t *)
677 runtime->set_virtual_address_map;
679 * Make efi_get_time can be called before entering
682 efi.get_time = phys_efi_get_time;
683 early_iounmap(runtime, sizeof(efi_runtime_services_t));
688 static int __init efi_memmap_init(void)
690 /* Map the EFI memory map */
691 memmap.map = early_ioremap((unsigned long)memmap.phys_map,
692 memmap.nr_map * memmap.desc_size);
693 if (memmap.map == NULL) {
694 pr_err("Could not map the memory map!\n");
697 memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
705 void __init efi_init(void)
708 char vendor[100] = "unknown";
713 if (boot_params.efi_info.efi_systab_hi ||
714 boot_params.efi_info.efi_memmap_hi) {
715 pr_info("Table located above 4GB, disabling EFI.\n");
718 efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
720 efi_phys.systab = (efi_system_table_t *)
721 (boot_params.efi_info.efi_systab |
722 ((__u64)boot_params.efi_info.efi_systab_hi<<32));
725 if (efi_systab_init(efi_phys.systab))
728 set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
731 * Show what we know for posterity
733 c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
735 for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
739 pr_err("Could not map the firmware vendor!\n");
740 early_iounmap(tmp, 2);
742 pr_info("EFI v%u.%.02u by %s\n",
743 efi.systab->hdr.revision >> 16,
744 efi.systab->hdr.revision & 0xffff, vendor);
746 if (efi_config_init(efi.systab->tables, efi.systab->nr_tables))
749 set_bit(EFI_CONFIG_TABLES, &x86_efi_facility);
752 * Note: We currently don't support runtime services on an EFI
753 * that doesn't match the kernel 32/64-bit mode.
756 if (!efi_is_native())
757 pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
759 if (disable_runtime || efi_runtime_init())
761 set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
764 if (efi_memmap_init())
767 set_bit(EFI_MEMMAP, &x86_efi_facility);
770 if (efi_is_native()) {
771 x86_platform.get_wallclock = efi_get_time;
772 x86_platform.set_wallclock = efi_set_rtc_mmss;
781 void __init efi_late_init(void)
786 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
790 addr = md->virt_addr;
791 npages = md->num_pages;
793 memrange_efi_to_native(&addr, &npages);
796 set_memory_x(addr, npages);
798 set_memory_nx(addr, npages);
801 static void __init runtime_code_page_mkexec(void)
803 efi_memory_desc_t *md;
806 /* Make EFI runtime service code area executable */
807 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
810 if (md->type != EFI_RUNTIME_SERVICES_CODE)
813 efi_set_executable(md, true);
818 * We can't ioremap data in EFI boot services RAM, because we've already mapped
819 * it as RAM. So, look it up in the existing EFI memory map instead. Only
820 * callable after efi_enter_virtual_mode and before efi_free_boot_services.
822 void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
825 if (WARN_ON(!memmap.map))
827 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
828 efi_memory_desc_t *md = p;
829 u64 size = md->num_pages << EFI_PAGE_SHIFT;
830 u64 end = md->phys_addr + size;
831 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
832 md->type != EFI_BOOT_SERVICES_CODE &&
833 md->type != EFI_BOOT_SERVICES_DATA)
837 if (phys_addr >= md->phys_addr && phys_addr < end) {
838 phys_addr += md->virt_addr - md->phys_addr;
839 return (__force void __iomem *)(unsigned long)phys_addr;
845 void efi_memory_uc(u64 addr, unsigned long size)
847 unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
850 npages = round_up(size, page_shift) / page_shift;
851 memrange_efi_to_native(&addr, &npages);
852 set_memory_uc(addr, npages);
856 * This function will switch the EFI runtime services to virtual mode.
857 * Essentially, look through the EFI memmap and map every region that
858 * has the runtime attribute bit set in its memory descriptor and update
859 * that memory descriptor with the virtual address obtained from ioremap().
860 * This enables the runtime services to be called without having to
861 * thunk back into physical mode for every invocation.
863 void __init efi_enter_virtual_mode(void)
865 efi_memory_desc_t *md, *prev_md = NULL;
868 u64 end, systab, start_pfn, end_pfn;
869 void *p, *va, *new_memmap = NULL;
875 * We don't do virtual mode, since we don't do runtime services, on
879 if (!efi_is_native()) {
884 /* Merge contiguous regions of the same type and attribute */
885 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
894 if (prev_md->type != md->type ||
895 prev_md->attribute != md->attribute) {
900 prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
902 if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
903 prev_md->num_pages += md->num_pages;
904 md->type = EFI_RESERVED_TYPE;
911 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
913 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
914 md->type != EFI_BOOT_SERVICES_CODE &&
915 md->type != EFI_BOOT_SERVICES_DATA)
918 size = md->num_pages << EFI_PAGE_SHIFT;
919 end = md->phys_addr + size;
921 start_pfn = PFN_DOWN(md->phys_addr);
922 end_pfn = PFN_UP(end);
923 if (pfn_range_is_mapped(start_pfn, end_pfn)) {
924 va = __va(md->phys_addr);
926 if (!(md->attribute & EFI_MEMORY_WB))
927 efi_memory_uc((u64)(unsigned long)va, size);
929 va = efi_ioremap(md->phys_addr, size,
930 md->type, md->attribute);
932 md->virt_addr = (u64) (unsigned long) va;
935 pr_err("ioremap of 0x%llX failed!\n",
936 (unsigned long long)md->phys_addr);
940 systab = (u64) (unsigned long) efi_phys.systab;
941 if (md->phys_addr <= systab && systab < end) {
942 systab += md->virt_addr - md->phys_addr;
943 efi.systab = (efi_system_table_t *) (unsigned long) systab;
945 new_memmap = krealloc(new_memmap,
946 (count + 1) * memmap.desc_size,
948 memcpy(new_memmap + (count * memmap.desc_size), md,
955 status = phys_efi_set_virtual_address_map(
956 memmap.desc_size * count,
959 (efi_memory_desc_t *)__pa(new_memmap));
961 if (status != EFI_SUCCESS) {
962 pr_alert("Unable to switch EFI into virtual mode "
963 "(status=%lx)!\n", status);
964 panic("EFI call to SetVirtualAddressMap() failed!");
968 * Now that EFI is in virtual mode, update the function
969 * pointers in the runtime service table to the new virtual addresses.
971 * Call EFI services through wrapper functions.
973 efi.runtime_version = efi_systab.hdr.revision;
974 efi.get_time = virt_efi_get_time;
975 efi.set_time = virt_efi_set_time;
976 efi.get_wakeup_time = virt_efi_get_wakeup_time;
977 efi.set_wakeup_time = virt_efi_set_wakeup_time;
978 efi.get_variable = virt_efi_get_variable;
979 efi.get_next_variable = virt_efi_get_next_variable;
980 efi.set_variable = virt_efi_set_variable;
981 efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
982 efi.reset_system = virt_efi_reset_system;
983 efi.set_virtual_address_map = NULL;
984 efi.query_variable_info = virt_efi_query_variable_info;
985 efi.update_capsule = virt_efi_update_capsule;
986 efi.query_capsule_caps = virt_efi_query_capsule_caps;
987 if (__supported_pte_mask & _PAGE_NX)
988 runtime_code_page_mkexec();
992 /* clean DUMMY object */
993 efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
994 EFI_VARIABLE_NON_VOLATILE |
995 EFI_VARIABLE_BOOTSERVICE_ACCESS |
996 EFI_VARIABLE_RUNTIME_ACCESS,
1001 * Convenience functions to obtain memory types and attributes
1003 u32 efi_mem_type(unsigned long phys_addr)
1005 efi_memory_desc_t *md;
1008 if (!efi_enabled(EFI_MEMMAP))
1011 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1013 if ((md->phys_addr <= phys_addr) &&
1014 (phys_addr < (md->phys_addr +
1015 (md->num_pages << EFI_PAGE_SHIFT))))
1021 u64 efi_mem_attributes(unsigned long phys_addr)
1023 efi_memory_desc_t *md;
1026 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1028 if ((md->phys_addr <= phys_addr) &&
1029 (phys_addr < (md->phys_addr +
1030 (md->num_pages << EFI_PAGE_SHIFT))))
1031 return md->attribute;
1037 * Some firmware has serious problems when using more than 50% of the EFI
1038 * variable store, i.e. it triggers bugs that can brick machines. Ensure that
1039 * we never use more than this safe limit.
1041 * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
1044 efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
1046 efi_status_t status;
1047 u64 storage_size, remaining_size, max_size;
1049 if (!(attributes & EFI_VARIABLE_NON_VOLATILE))
1052 status = efi.query_variable_info(attributes, &storage_size,
1053 &remaining_size, &max_size);
1054 if (status != EFI_SUCCESS)
1058 * Some firmware implementations refuse to boot if there's insufficient
1059 * space in the variable store. We account for that by refusing the
1060 * write if permitting it would reduce the available space to under
1061 * 5KB. This figure was provided by Samsung, so should be safe.
1063 if ((remaining_size - size < EFI_MIN_RESERVE) &&
1064 !efi_no_storage_paranoia) {
1067 * Triggering garbage collection may require that the firmware
1068 * generate a real EFI_OUT_OF_RESOURCES error. We can force
1069 * that by attempting to use more space than is available.
1071 unsigned long dummy_size = remaining_size + 1024;
1072 void *dummy = kzalloc(dummy_size, GFP_ATOMIC);
1075 return EFI_OUT_OF_RESOURCES;
1077 status = efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
1078 EFI_VARIABLE_NON_VOLATILE |
1079 EFI_VARIABLE_BOOTSERVICE_ACCESS |
1080 EFI_VARIABLE_RUNTIME_ACCESS,
1083 if (status == EFI_SUCCESS) {
1085 * This should have failed, so if it didn't make sure
1086 * that we delete it...
1088 efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
1089 EFI_VARIABLE_NON_VOLATILE |
1090 EFI_VARIABLE_BOOTSERVICE_ACCESS |
1091 EFI_VARIABLE_RUNTIME_ACCESS,
1098 * The runtime code may now have triggered a garbage collection
1099 * run, so check the variable info again
1101 status = efi.query_variable_info(attributes, &storage_size,
1102 &remaining_size, &max_size);
1104 if (status != EFI_SUCCESS)
1108 * There still isn't enough room, so return an error
1110 if (remaining_size - size < EFI_MIN_RESERVE)
1111 return EFI_OUT_OF_RESOURCES;
1116 EXPORT_SYMBOL_GPL(efi_query_variable_store);