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>
15 * Copyright (C) 2013 SuSE Labs
16 * Borislav Petkov <bp@suse.de> - runtime services VA mapping
18 * Copied from efi_32.c to eliminate the duplicated code between EFI
19 * 32/64 support code. --ying 2007-10-26
21 * All EFI Runtime Services are not implemented yet as EFI only
22 * supports physical mode addressing on SoftSDV. This is to be fixed
23 * in a future version. --drummond 1999-07-20
25 * Implemented EFI runtime services and virtual mode calls. --davidm
27 * Goutham Rao: <goutham.rao@intel.com>
28 * Skip non-WB memory and ignore empty memory ranges.
31 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
33 #include <linux/kernel.h>
34 #include <linux/init.h>
35 #include <linux/efi.h>
36 #include <linux/efi-bgrt.h>
37 #include <linux/export.h>
38 #include <linux/bootmem.h>
39 #include <linux/slab.h>
40 #include <linux/memblock.h>
41 #include <linux/spinlock.h>
42 #include <linux/uaccess.h>
43 #include <linux/time.h>
45 #include <linux/reboot.h>
46 #include <linux/bcd.h>
48 #include <asm/setup.h>
51 #include <asm/cacheflush.h>
52 #include <asm/tlbflush.h>
53 #include <asm/x86_init.h>
55 #include <asm/uv/uv.h>
59 struct efi_memory_map memmap
;
61 static struct efi efi_phys __initdata
;
62 static efi_system_table_t efi_systab __initdata
;
64 static efi_config_table_type_t arch_tables
[] __initdata
= {
66 {UV_SYSTEM_TABLE_GUID
, "UVsystab", &efi
.uv_systab
},
68 {NULL_GUID
, NULL
, NULL
},
71 u64 efi_setup
; /* efi setup_data physical address */
73 static int add_efi_memmap __initdata
;
74 static int __init
setup_add_efi_memmap(char *arg
)
79 early_param("add_efi_memmap", setup_add_efi_memmap
);
81 static efi_status_t __init
phys_efi_set_virtual_address_map(
82 unsigned long memory_map_size
,
83 unsigned long descriptor_size
,
84 u32 descriptor_version
,
85 efi_memory_desc_t
*virtual_map
)
91 save_pgd
= efi_call_phys_prolog();
93 /* Disable interrupts around EFI calls: */
94 local_irq_save(flags
);
95 status
= efi_call_phys(efi_phys
.set_virtual_address_map
,
96 memory_map_size
, descriptor_size
,
97 descriptor_version
, virtual_map
);
98 local_irq_restore(flags
);
100 efi_call_phys_epilog(save_pgd
);
105 void efi_get_time(struct timespec
*now
)
111 status
= efi
.get_time(&eft
, &cap
);
112 if (status
!= EFI_SUCCESS
)
113 pr_err("Oops: efitime: can't read time!\n");
115 now
->tv_sec
= mktime(eft
.year
, eft
.month
, eft
.day
, eft
.hour
,
116 eft
.minute
, eft
.second
);
120 void __init
efi_find_mirror(void)
123 u64 mirror_size
= 0, total_size
= 0;
125 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
126 efi_memory_desc_t
*md
= p
;
127 unsigned long long start
= md
->phys_addr
;
128 unsigned long long size
= md
->num_pages
<< EFI_PAGE_SHIFT
;
131 if (md
->attribute
& EFI_MEMORY_MORE_RELIABLE
) {
132 memblock_mark_mirror(start
, size
);
137 pr_info("Memory: %lldM/%lldM mirrored memory\n",
138 mirror_size
>>20, total_size
>>20);
142 * Tell the kernel about the EFI memory map. This might include
143 * more than the max 128 entries that can fit in the e820 legacy
144 * (zeropage) memory map.
147 static void __init
do_add_efi_memmap(void)
151 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
152 efi_memory_desc_t
*md
= p
;
153 unsigned long long start
= md
->phys_addr
;
154 unsigned long long size
= md
->num_pages
<< EFI_PAGE_SHIFT
;
158 case EFI_LOADER_CODE
:
159 case EFI_LOADER_DATA
:
160 case EFI_BOOT_SERVICES_CODE
:
161 case EFI_BOOT_SERVICES_DATA
:
162 case EFI_CONVENTIONAL_MEMORY
:
163 if (md
->attribute
& EFI_MEMORY_WB
)
164 e820_type
= E820_RAM
;
166 e820_type
= E820_RESERVED
;
168 case EFI_ACPI_RECLAIM_MEMORY
:
169 e820_type
= E820_ACPI
;
171 case EFI_ACPI_MEMORY_NVS
:
172 e820_type
= E820_NVS
;
174 case EFI_UNUSABLE_MEMORY
:
175 e820_type
= E820_UNUSABLE
;
179 * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
180 * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
181 * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
183 e820_type
= E820_RESERVED
;
186 e820_add_region(start
, size
, e820_type
);
188 sanitize_e820_map(e820
.map
, ARRAY_SIZE(e820
.map
), &e820
.nr_map
);
191 int __init
efi_memblock_x86_reserve_range(void)
193 struct efi_info
*e
= &boot_params
.efi_info
;
196 if (efi_enabled(EFI_PARAVIRT
))
200 /* Can't handle data above 4GB at this time */
201 if (e
->efi_memmap_hi
) {
202 pr_err("Memory map is above 4GB, disabling EFI.\n");
205 pmap
= e
->efi_memmap
;
207 pmap
= (e
->efi_memmap
| ((__u64
)e
->efi_memmap_hi
<< 32));
209 memmap
.phys_map
= (void *)pmap
;
210 memmap
.nr_map
= e
->efi_memmap_size
/
212 memmap
.desc_size
= e
->efi_memdesc_size
;
213 memmap
.desc_version
= e
->efi_memdesc_version
;
215 memblock_reserve(pmap
, memmap
.nr_map
* memmap
.desc_size
);
217 efi
.memmap
= &memmap
;
222 static void __init
print_efi_memmap(void)
225 efi_memory_desc_t
*md
;
229 for (p
= memmap
.map
, i
= 0;
231 p
+= memmap
.desc_size
, i
++) {
235 pr_info("mem%02u: %s range=[0x%016llx-0x%016llx) (%lluMB)\n",
236 i
, efi_md_typeattr_format(buf
, sizeof(buf
), md
),
238 md
->phys_addr
+ (md
->num_pages
<< EFI_PAGE_SHIFT
),
239 (md
->num_pages
>> (20 - EFI_PAGE_SHIFT
)));
241 #endif /* EFI_DEBUG */
244 void __init
efi_unmap_memmap(void)
246 clear_bit(EFI_MEMMAP
, &efi
.flags
);
248 early_memunmap(memmap
.map
, memmap
.nr_map
* memmap
.desc_size
);
253 static int __init
efi_systab_init(void *phys
)
255 if (efi_enabled(EFI_64BIT
)) {
256 efi_system_table_64_t
*systab64
;
257 struct efi_setup_data
*data
= NULL
;
261 data
= early_memremap(efi_setup
, sizeof(*data
));
265 systab64
= early_memremap((unsigned long)phys
,
267 if (systab64
== NULL
) {
268 pr_err("Couldn't map the system table!\n");
270 early_memunmap(data
, sizeof(*data
));
274 efi_systab
.hdr
= systab64
->hdr
;
275 efi_systab
.fw_vendor
= data
? (unsigned long)data
->fw_vendor
:
277 tmp
|= data
? data
->fw_vendor
: systab64
->fw_vendor
;
278 efi_systab
.fw_revision
= systab64
->fw_revision
;
279 efi_systab
.con_in_handle
= systab64
->con_in_handle
;
280 tmp
|= systab64
->con_in_handle
;
281 efi_systab
.con_in
= systab64
->con_in
;
282 tmp
|= systab64
->con_in
;
283 efi_systab
.con_out_handle
= systab64
->con_out_handle
;
284 tmp
|= systab64
->con_out_handle
;
285 efi_systab
.con_out
= systab64
->con_out
;
286 tmp
|= systab64
->con_out
;
287 efi_systab
.stderr_handle
= systab64
->stderr_handle
;
288 tmp
|= systab64
->stderr_handle
;
289 efi_systab
.stderr
= systab64
->stderr
;
290 tmp
|= systab64
->stderr
;
291 efi_systab
.runtime
= data
?
292 (void *)(unsigned long)data
->runtime
:
293 (void *)(unsigned long)systab64
->runtime
;
294 tmp
|= data
? data
->runtime
: systab64
->runtime
;
295 efi_systab
.boottime
= (void *)(unsigned long)systab64
->boottime
;
296 tmp
|= systab64
->boottime
;
297 efi_systab
.nr_tables
= systab64
->nr_tables
;
298 efi_systab
.tables
= data
? (unsigned long)data
->tables
:
300 tmp
|= data
? data
->tables
: systab64
->tables
;
302 early_memunmap(systab64
, sizeof(*systab64
));
304 early_memunmap(data
, sizeof(*data
));
307 pr_err("EFI data located above 4GB, disabling EFI.\n");
312 efi_system_table_32_t
*systab32
;
314 systab32
= early_memremap((unsigned long)phys
,
316 if (systab32
== NULL
) {
317 pr_err("Couldn't map the system table!\n");
321 efi_systab
.hdr
= systab32
->hdr
;
322 efi_systab
.fw_vendor
= systab32
->fw_vendor
;
323 efi_systab
.fw_revision
= systab32
->fw_revision
;
324 efi_systab
.con_in_handle
= systab32
->con_in_handle
;
325 efi_systab
.con_in
= systab32
->con_in
;
326 efi_systab
.con_out_handle
= systab32
->con_out_handle
;
327 efi_systab
.con_out
= systab32
->con_out
;
328 efi_systab
.stderr_handle
= systab32
->stderr_handle
;
329 efi_systab
.stderr
= systab32
->stderr
;
330 efi_systab
.runtime
= (void *)(unsigned long)systab32
->runtime
;
331 efi_systab
.boottime
= (void *)(unsigned long)systab32
->boottime
;
332 efi_systab
.nr_tables
= systab32
->nr_tables
;
333 efi_systab
.tables
= systab32
->tables
;
335 early_memunmap(systab32
, sizeof(*systab32
));
338 efi
.systab
= &efi_systab
;
341 * Verify the EFI Table
343 if (efi
.systab
->hdr
.signature
!= EFI_SYSTEM_TABLE_SIGNATURE
) {
344 pr_err("System table signature incorrect!\n");
347 if ((efi
.systab
->hdr
.revision
>> 16) == 0)
348 pr_err("Warning: System table version %d.%02d, expected 1.00 or greater!\n",
349 efi
.systab
->hdr
.revision
>> 16,
350 efi
.systab
->hdr
.revision
& 0xffff);
352 set_bit(EFI_SYSTEM_TABLES
, &efi
.flags
);
357 static int __init
efi_runtime_init32(void)
359 efi_runtime_services_32_t
*runtime
;
361 runtime
= early_memremap((unsigned long)efi
.systab
->runtime
,
362 sizeof(efi_runtime_services_32_t
));
364 pr_err("Could not map the runtime service table!\n");
369 * We will only need *early* access to the SetVirtualAddressMap
370 * EFI runtime service. All other runtime services will be called
371 * via the virtual mapping.
373 efi_phys
.set_virtual_address_map
=
374 (efi_set_virtual_address_map_t
*)
375 (unsigned long)runtime
->set_virtual_address_map
;
376 early_memunmap(runtime
, sizeof(efi_runtime_services_32_t
));
381 static int __init
efi_runtime_init64(void)
383 efi_runtime_services_64_t
*runtime
;
385 runtime
= early_memremap((unsigned long)efi
.systab
->runtime
,
386 sizeof(efi_runtime_services_64_t
));
388 pr_err("Could not map the runtime service table!\n");
393 * We will only need *early* access to the SetVirtualAddressMap
394 * EFI runtime service. All other runtime services will be called
395 * via the virtual mapping.
397 efi_phys
.set_virtual_address_map
=
398 (efi_set_virtual_address_map_t
*)
399 (unsigned long)runtime
->set_virtual_address_map
;
400 early_memunmap(runtime
, sizeof(efi_runtime_services_64_t
));
405 static int __init
efi_runtime_init(void)
410 * Check out the runtime services table. We need to map
411 * the runtime services table so that we can grab the physical
412 * address of several of the EFI runtime functions, needed to
413 * set the firmware into virtual mode.
415 * When EFI_PARAVIRT is in force then we could not map runtime
416 * service memory region because we do not have direct access to it.
417 * However, runtime services are available through proxy functions
418 * (e.g. in case of Xen dom0 EFI implementation they call special
419 * hypercall which executes relevant EFI functions) and that is why
420 * they are always enabled.
423 if (!efi_enabled(EFI_PARAVIRT
)) {
424 if (efi_enabled(EFI_64BIT
))
425 rv
= efi_runtime_init64();
427 rv
= efi_runtime_init32();
433 set_bit(EFI_RUNTIME_SERVICES
, &efi
.flags
);
438 static int __init
efi_memmap_init(void)
440 if (efi_enabled(EFI_PARAVIRT
))
443 /* Map the EFI memory map */
444 memmap
.map
= early_memremap((unsigned long)memmap
.phys_map
,
445 memmap
.nr_map
* memmap
.desc_size
);
446 if (memmap
.map
== NULL
) {
447 pr_err("Could not map the memory map!\n");
450 memmap
.map_end
= memmap
.map
+ (memmap
.nr_map
* memmap
.desc_size
);
455 set_bit(EFI_MEMMAP
, &efi
.flags
);
460 void __init
efi_init(void)
463 char vendor
[100] = "unknown";
468 if (boot_params
.efi_info
.efi_systab_hi
||
469 boot_params
.efi_info
.efi_memmap_hi
) {
470 pr_info("Table located above 4GB, disabling EFI.\n");
473 efi_phys
.systab
= (efi_system_table_t
*)boot_params
.efi_info
.efi_systab
;
475 efi_phys
.systab
= (efi_system_table_t
*)
476 (boot_params
.efi_info
.efi_systab
|
477 ((__u64
)boot_params
.efi_info
.efi_systab_hi
<<32));
480 if (efi_systab_init(efi_phys
.systab
))
483 efi
.config_table
= (unsigned long)efi
.systab
->tables
;
484 efi
.fw_vendor
= (unsigned long)efi
.systab
->fw_vendor
;
485 efi
.runtime
= (unsigned long)efi
.systab
->runtime
;
488 * Show what we know for posterity
490 c16
= tmp
= early_memremap(efi
.systab
->fw_vendor
, 2);
492 for (i
= 0; i
< sizeof(vendor
) - 1 && *c16
; ++i
)
496 pr_err("Could not map the firmware vendor!\n");
497 early_memunmap(tmp
, 2);
499 pr_info("EFI v%u.%.02u by %s\n",
500 efi
.systab
->hdr
.revision
>> 16,
501 efi
.systab
->hdr
.revision
& 0xffff, vendor
);
503 if (efi_reuse_config(efi
.systab
->tables
, efi
.systab
->nr_tables
))
506 if (efi_config_init(arch_tables
))
510 * Note: We currently don't support runtime services on an EFI
511 * that doesn't match the kernel 32/64-bit mode.
514 if (!efi_runtime_supported())
515 pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
517 if (efi_runtime_disabled() || efi_runtime_init())
520 if (efi_memmap_init())
523 if (efi_enabled(EFI_DBG
))
529 void __init
efi_late_init(void)
534 void __init
efi_set_executable(efi_memory_desc_t
*md
, bool executable
)
538 addr
= md
->virt_addr
;
539 npages
= md
->num_pages
;
541 memrange_efi_to_native(&addr
, &npages
);
544 set_memory_x(addr
, npages
);
546 set_memory_nx(addr
, npages
);
549 void __init
runtime_code_page_mkexec(void)
551 efi_memory_desc_t
*md
;
554 /* Make EFI runtime service code area executable */
555 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
558 if (md
->type
!= EFI_RUNTIME_SERVICES_CODE
)
561 efi_set_executable(md
, true);
565 void __init
efi_memory_uc(u64 addr
, unsigned long size
)
567 unsigned long page_shift
= 1UL << EFI_PAGE_SHIFT
;
570 npages
= round_up(size
, page_shift
) / page_shift
;
571 memrange_efi_to_native(&addr
, &npages
);
572 set_memory_uc(addr
, npages
);
575 void __init
old_map_region(efi_memory_desc_t
*md
)
577 u64 start_pfn
, end_pfn
, end
;
581 start_pfn
= PFN_DOWN(md
->phys_addr
);
582 size
= md
->num_pages
<< PAGE_SHIFT
;
583 end
= md
->phys_addr
+ size
;
584 end_pfn
= PFN_UP(end
);
586 if (pfn_range_is_mapped(start_pfn
, end_pfn
)) {
587 va
= __va(md
->phys_addr
);
589 if (!(md
->attribute
& EFI_MEMORY_WB
))
590 efi_memory_uc((u64
)(unsigned long)va
, size
);
592 va
= efi_ioremap(md
->phys_addr
, size
,
593 md
->type
, md
->attribute
);
595 md
->virt_addr
= (u64
) (unsigned long) va
;
597 pr_err("ioremap of 0x%llX failed!\n",
598 (unsigned long long)md
->phys_addr
);
601 /* Merge contiguous regions of the same type and attribute */
602 static void __init
efi_merge_regions(void)
605 efi_memory_desc_t
*md
, *prev_md
= NULL
;
607 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
616 if (prev_md
->type
!= md
->type
||
617 prev_md
->attribute
!= md
->attribute
) {
622 prev_size
= prev_md
->num_pages
<< EFI_PAGE_SHIFT
;
624 if (md
->phys_addr
== (prev_md
->phys_addr
+ prev_size
)) {
625 prev_md
->num_pages
+= md
->num_pages
;
626 md
->type
= EFI_RESERVED_TYPE
;
634 static void __init
get_systab_virt_addr(efi_memory_desc_t
*md
)
639 size
= md
->num_pages
<< EFI_PAGE_SHIFT
;
640 end
= md
->phys_addr
+ size
;
641 systab
= (u64
)(unsigned long)efi_phys
.systab
;
642 if (md
->phys_addr
<= systab
&& systab
< end
) {
643 systab
+= md
->virt_addr
- md
->phys_addr
;
644 efi
.systab
= (efi_system_table_t
*)(unsigned long)systab
;
648 static void __init
save_runtime_map(void)
651 efi_memory_desc_t
*md
;
652 void *tmp
, *p
, *q
= NULL
;
655 if (efi_enabled(EFI_OLD_MEMMAP
))
658 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
661 if (!(md
->attribute
& EFI_MEMORY_RUNTIME
) ||
662 (md
->type
== EFI_BOOT_SERVICES_CODE
) ||
663 (md
->type
== EFI_BOOT_SERVICES_DATA
))
665 tmp
= krealloc(q
, (count
+ 1) * memmap
.desc_size
, GFP_KERNEL
);
670 memcpy(q
+ count
* memmap
.desc_size
, md
, memmap
.desc_size
);
674 efi_runtime_map_setup(q
, count
, memmap
.desc_size
);
679 pr_err("Error saving runtime map, efi runtime on kexec non-functional!!\n");
683 static void *realloc_pages(void *old_memmap
, int old_shift
)
687 ret
= (void *)__get_free_pages(GFP_KERNEL
, old_shift
+ 1);
692 * A first-time allocation doesn't have anything to copy.
697 memcpy(ret
, old_memmap
, PAGE_SIZE
<< old_shift
);
700 free_pages((unsigned long)old_memmap
, old_shift
);
705 * Map the efi memory ranges of the runtime services and update new_mmap with
708 static void * __init
efi_map_regions(int *count
, int *pg_shift
)
710 void *p
, *new_memmap
= NULL
;
711 unsigned long left
= 0;
712 efi_memory_desc_t
*md
;
714 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
716 if (!(md
->attribute
& EFI_MEMORY_RUNTIME
)) {
718 if (md
->type
!= EFI_BOOT_SERVICES_CODE
&&
719 md
->type
!= EFI_BOOT_SERVICES_DATA
)
725 get_systab_virt_addr(md
);
727 if (left
< memmap
.desc_size
) {
728 new_memmap
= realloc_pages(new_memmap
, *pg_shift
);
732 left
+= PAGE_SIZE
<< *pg_shift
;
736 memcpy(new_memmap
+ (*count
* memmap
.desc_size
), md
,
739 left
-= memmap
.desc_size
;
746 static void __init
kexec_enter_virtual_mode(void)
749 efi_memory_desc_t
*md
;
755 * We don't do virtual mode, since we don't do runtime services, on
758 if (!efi_is_native()) {
760 clear_bit(EFI_RUNTIME_SERVICES
, &efi
.flags
);
765 * Map efi regions which were passed via setup_data. The virt_addr is a
766 * fixed addr which was used in first kernel of a kexec boot.
768 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
770 efi_map_region_fixed(md
); /* FIXME: add error handling */
771 get_systab_virt_addr(md
);
778 efi_sync_low_kernel_mappings();
781 * Now that EFI is in virtual mode, update the function
782 * pointers in the runtime service table to the new virtual addresses.
784 * Call EFI services through wrapper functions.
786 efi
.runtime_version
= efi_systab
.hdr
.revision
;
788 efi_native_runtime_setup();
790 efi
.set_virtual_address_map
= NULL
;
792 if (efi_enabled(EFI_OLD_MEMMAP
) && (__supported_pte_mask
& _PAGE_NX
))
793 runtime_code_page_mkexec();
795 /* clean DUMMY object */
796 efi_delete_dummy_variable();
801 * This function will switch the EFI runtime services to virtual mode.
802 * Essentially, we look through the EFI memmap and map every region that
803 * has the runtime attribute bit set in its memory descriptor into the
804 * ->trampoline_pgd page table using a top-down VA allocation scheme.
806 * The old method which used to update that memory descriptor with the
807 * virtual address obtained from ioremap() is still supported when the
808 * kernel is booted with efi=old_map on its command line. Same old
809 * method enabled the runtime services to be called without having to
810 * thunk back into physical mode for every invocation.
812 * The new method does a pagetable switch in a preemption-safe manner
813 * so that we're in a different address space when calling a runtime
814 * function. For function arguments passing we do copy the PGDs of the
815 * kernel page table into ->trampoline_pgd prior to each call.
817 * Specially for kexec boot, efi runtime maps in previous kernel should
818 * be passed in via setup_data. In that case runtime ranges will be mapped
819 * to the same virtual addresses as the first kernel, see
820 * kexec_enter_virtual_mode().
822 static void __init
__efi_enter_virtual_mode(void)
824 int count
= 0, pg_shift
= 0;
825 void *new_memmap
= NULL
;
831 new_memmap
= efi_map_regions(&count
, &pg_shift
);
833 pr_err("Error reallocating memory, EFI runtime non-functional!\n");
834 clear_bit(EFI_RUNTIME_SERVICES
, &efi
.flags
);
842 if (efi_setup_page_tables(__pa(new_memmap
), 1 << pg_shift
)) {
843 clear_bit(EFI_RUNTIME_SERVICES
, &efi
.flags
);
847 efi_sync_low_kernel_mappings();
848 efi_dump_pagetable();
850 if (efi_is_native()) {
851 status
= phys_efi_set_virtual_address_map(
852 memmap
.desc_size
* count
,
855 (efi_memory_desc_t
*)__pa(new_memmap
));
857 status
= efi_thunk_set_virtual_address_map(
858 efi_phys
.set_virtual_address_map
,
859 memmap
.desc_size
* count
,
862 (efi_memory_desc_t
*)__pa(new_memmap
));
865 if (status
!= EFI_SUCCESS
) {
866 pr_alert("Unable to switch EFI into virtual mode (status=%lx)!\n",
868 panic("EFI call to SetVirtualAddressMap() failed!");
872 * Now that EFI is in virtual mode, update the function
873 * pointers in the runtime service table to the new virtual addresses.
875 * Call EFI services through wrapper functions.
877 efi
.runtime_version
= efi_systab
.hdr
.revision
;
880 efi_native_runtime_setup();
882 efi_thunk_runtime_setup();
884 efi
.set_virtual_address_map
= NULL
;
886 efi_runtime_mkexec();
889 * We mapped the descriptor array into the EFI pagetable above but we're
890 * not unmapping it here. Here's why:
892 * We're copying select PGDs from the kernel page table to the EFI page
893 * table and when we do so and make changes to those PGDs like unmapping
894 * stuff from them, those changes appear in the kernel page table and we
897 * From setup_real_mode():
900 * trampoline_pgd[0] = init_level4_pgt[pgd_index(__PAGE_OFFSET)].pgd;
902 * In this particular case, our allocation is in PGD 0 of the EFI page
903 * table but we've copied that PGD from PGD[272] of the EFI page table:
905 * pgd_index(__PAGE_OFFSET = 0xffff880000000000) = 272
907 * where the direct memory mapping in kernel space is.
909 * new_memmap's VA comes from that direct mapping and thus clearing it,
910 * it would get cleared in the kernel page table too.
912 * efi_cleanup_page_tables(__pa(new_memmap), 1 << pg_shift);
914 free_pages((unsigned long)new_memmap
, pg_shift
);
916 /* clean DUMMY object */
917 efi_delete_dummy_variable();
920 void __init
efi_enter_virtual_mode(void)
922 if (efi_enabled(EFI_PARAVIRT
))
926 kexec_enter_virtual_mode();
928 __efi_enter_virtual_mode();
932 * Convenience functions to obtain memory types and attributes
934 u32
efi_mem_type(unsigned long phys_addr
)
936 efi_memory_desc_t
*md
;
939 if (!efi_enabled(EFI_MEMMAP
))
942 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
944 if ((md
->phys_addr
<= phys_addr
) &&
945 (phys_addr
< (md
->phys_addr
+
946 (md
->num_pages
<< EFI_PAGE_SHIFT
))))
952 u64
efi_mem_attributes(unsigned long phys_addr
)
954 efi_memory_desc_t
*md
;
957 if (!efi_enabled(EFI_MEMMAP
))
960 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
962 if ((md
->phys_addr
<= phys_addr
) &&
963 (phys_addr
< (md
->phys_addr
+
964 (md
->num_pages
<< EFI_PAGE_SHIFT
))))
965 return md
->attribute
;
970 static int __init
arch_parse_efi_cmdline(char *str
)
972 if (parse_option_str(str
, "old_map"))
973 set_bit(EFI_OLD_MEMMAP
, &efi
.flags
);
974 if (parse_option_str(str
, "debug"))
975 set_bit(EFI_DBG
, &efi
.flags
);
979 early_param("efi", arch_parse_efi_cmdline
);