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
)
89 efi_call_phys_prolog();
90 status
= efi_call_phys(efi_phys
.set_virtual_address_map
,
91 memory_map_size
, descriptor_size
,
92 descriptor_version
, virtual_map
);
93 efi_call_phys_epilog();
97 void efi_get_time(struct timespec
*now
)
103 status
= efi
.get_time(&eft
, &cap
);
104 if (status
!= EFI_SUCCESS
)
105 pr_err("Oops: efitime: can't read time!\n");
107 now
->tv_sec
= mktime(eft
.year
, eft
.month
, eft
.day
, eft
.hour
,
108 eft
.minute
, eft
.second
);
113 * Tell the kernel about the EFI memory map. This might include
114 * more than the max 128 entries that can fit in the e820 legacy
115 * (zeropage) memory map.
118 static void __init
do_add_efi_memmap(void)
122 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
123 efi_memory_desc_t
*md
= p
;
124 unsigned long long start
= md
->phys_addr
;
125 unsigned long long size
= md
->num_pages
<< EFI_PAGE_SHIFT
;
129 case EFI_LOADER_CODE
:
130 case EFI_LOADER_DATA
:
131 case EFI_BOOT_SERVICES_CODE
:
132 case EFI_BOOT_SERVICES_DATA
:
133 case EFI_CONVENTIONAL_MEMORY
:
134 if (md
->attribute
& EFI_MEMORY_WB
)
135 e820_type
= E820_RAM
;
137 e820_type
= E820_RESERVED
;
139 case EFI_ACPI_RECLAIM_MEMORY
:
140 e820_type
= E820_ACPI
;
142 case EFI_ACPI_MEMORY_NVS
:
143 e820_type
= E820_NVS
;
145 case EFI_UNUSABLE_MEMORY
:
146 e820_type
= E820_UNUSABLE
;
150 * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
151 * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
152 * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
154 e820_type
= E820_RESERVED
;
157 e820_add_region(start
, size
, e820_type
);
159 sanitize_e820_map(e820
.map
, ARRAY_SIZE(e820
.map
), &e820
.nr_map
);
162 int __init
efi_memblock_x86_reserve_range(void)
164 struct efi_info
*e
= &boot_params
.efi_info
;
167 if (efi_enabled(EFI_PARAVIRT
))
171 /* Can't handle data above 4GB at this time */
172 if (e
->efi_memmap_hi
) {
173 pr_err("Memory map is above 4GB, disabling EFI.\n");
176 pmap
= e
->efi_memmap
;
178 pmap
= (e
->efi_memmap
| ((__u64
)e
->efi_memmap_hi
<< 32));
180 memmap
.phys_map
= (void *)pmap
;
181 memmap
.nr_map
= e
->efi_memmap_size
/
183 memmap
.desc_size
= e
->efi_memdesc_size
;
184 memmap
.desc_version
= e
->efi_memdesc_version
;
186 memblock_reserve(pmap
, memmap
.nr_map
* memmap
.desc_size
);
188 efi
.memmap
= &memmap
;
193 static void __init
print_efi_memmap(void)
196 efi_memory_desc_t
*md
;
200 for (p
= memmap
.map
, i
= 0;
202 p
+= memmap
.desc_size
, i
++) {
206 pr_info("mem%02u: %s range=[0x%016llx-0x%016llx) (%lluMB)\n",
207 i
, efi_md_typeattr_format(buf
, sizeof(buf
), md
),
209 md
->phys_addr
+ (md
->num_pages
<< EFI_PAGE_SHIFT
),
210 (md
->num_pages
>> (20 - EFI_PAGE_SHIFT
)));
212 #endif /* EFI_DEBUG */
215 void __init
efi_unmap_memmap(void)
217 clear_bit(EFI_MEMMAP
, &efi
.flags
);
219 early_memunmap(memmap
.map
, memmap
.nr_map
* memmap
.desc_size
);
224 static int __init
efi_systab_init(void *phys
)
226 if (efi_enabled(EFI_64BIT
)) {
227 efi_system_table_64_t
*systab64
;
228 struct efi_setup_data
*data
= NULL
;
232 data
= early_memremap(efi_setup
, sizeof(*data
));
236 systab64
= early_memremap((unsigned long)phys
,
238 if (systab64
== NULL
) {
239 pr_err("Couldn't map the system table!\n");
241 early_memunmap(data
, sizeof(*data
));
245 efi_systab
.hdr
= systab64
->hdr
;
246 efi_systab
.fw_vendor
= data
? (unsigned long)data
->fw_vendor
:
248 tmp
|= data
? data
->fw_vendor
: systab64
->fw_vendor
;
249 efi_systab
.fw_revision
= systab64
->fw_revision
;
250 efi_systab
.con_in_handle
= systab64
->con_in_handle
;
251 tmp
|= systab64
->con_in_handle
;
252 efi_systab
.con_in
= systab64
->con_in
;
253 tmp
|= systab64
->con_in
;
254 efi_systab
.con_out_handle
= systab64
->con_out_handle
;
255 tmp
|= systab64
->con_out_handle
;
256 efi_systab
.con_out
= systab64
->con_out
;
257 tmp
|= systab64
->con_out
;
258 efi_systab
.stderr_handle
= systab64
->stderr_handle
;
259 tmp
|= systab64
->stderr_handle
;
260 efi_systab
.stderr
= systab64
->stderr
;
261 tmp
|= systab64
->stderr
;
262 efi_systab
.runtime
= data
?
263 (void *)(unsigned long)data
->runtime
:
264 (void *)(unsigned long)systab64
->runtime
;
265 tmp
|= data
? data
->runtime
: systab64
->runtime
;
266 efi_systab
.boottime
= (void *)(unsigned long)systab64
->boottime
;
267 tmp
|= systab64
->boottime
;
268 efi_systab
.nr_tables
= systab64
->nr_tables
;
269 efi_systab
.tables
= data
? (unsigned long)data
->tables
:
271 tmp
|= data
? data
->tables
: systab64
->tables
;
273 early_memunmap(systab64
, sizeof(*systab64
));
275 early_memunmap(data
, sizeof(*data
));
278 pr_err("EFI data located above 4GB, disabling EFI.\n");
283 efi_system_table_32_t
*systab32
;
285 systab32
= early_memremap((unsigned long)phys
,
287 if (systab32
== NULL
) {
288 pr_err("Couldn't map the system table!\n");
292 efi_systab
.hdr
= systab32
->hdr
;
293 efi_systab
.fw_vendor
= systab32
->fw_vendor
;
294 efi_systab
.fw_revision
= systab32
->fw_revision
;
295 efi_systab
.con_in_handle
= systab32
->con_in_handle
;
296 efi_systab
.con_in
= systab32
->con_in
;
297 efi_systab
.con_out_handle
= systab32
->con_out_handle
;
298 efi_systab
.con_out
= systab32
->con_out
;
299 efi_systab
.stderr_handle
= systab32
->stderr_handle
;
300 efi_systab
.stderr
= systab32
->stderr
;
301 efi_systab
.runtime
= (void *)(unsigned long)systab32
->runtime
;
302 efi_systab
.boottime
= (void *)(unsigned long)systab32
->boottime
;
303 efi_systab
.nr_tables
= systab32
->nr_tables
;
304 efi_systab
.tables
= systab32
->tables
;
306 early_memunmap(systab32
, sizeof(*systab32
));
309 efi
.systab
= &efi_systab
;
312 * Verify the EFI Table
314 if (efi
.systab
->hdr
.signature
!= EFI_SYSTEM_TABLE_SIGNATURE
) {
315 pr_err("System table signature incorrect!\n");
318 if ((efi
.systab
->hdr
.revision
>> 16) == 0)
319 pr_err("Warning: System table version %d.%02d, expected 1.00 or greater!\n",
320 efi
.systab
->hdr
.revision
>> 16,
321 efi
.systab
->hdr
.revision
& 0xffff);
323 set_bit(EFI_SYSTEM_TABLES
, &efi
.flags
);
328 static int __init
efi_runtime_init32(void)
330 efi_runtime_services_32_t
*runtime
;
332 runtime
= early_memremap((unsigned long)efi
.systab
->runtime
,
333 sizeof(efi_runtime_services_32_t
));
335 pr_err("Could not map the runtime service table!\n");
340 * We will only need *early* access to the SetVirtualAddressMap
341 * EFI runtime service. All other runtime services will be called
342 * via the virtual mapping.
344 efi_phys
.set_virtual_address_map
=
345 (efi_set_virtual_address_map_t
*)
346 (unsigned long)runtime
->set_virtual_address_map
;
347 early_memunmap(runtime
, sizeof(efi_runtime_services_32_t
));
352 static int __init
efi_runtime_init64(void)
354 efi_runtime_services_64_t
*runtime
;
356 runtime
= early_memremap((unsigned long)efi
.systab
->runtime
,
357 sizeof(efi_runtime_services_64_t
));
359 pr_err("Could not map the runtime service table!\n");
364 * We will only need *early* access to the SetVirtualAddressMap
365 * EFI runtime service. All other runtime services will be called
366 * via the virtual mapping.
368 efi_phys
.set_virtual_address_map
=
369 (efi_set_virtual_address_map_t
*)
370 (unsigned long)runtime
->set_virtual_address_map
;
371 early_memunmap(runtime
, sizeof(efi_runtime_services_64_t
));
376 static int __init
efi_runtime_init(void)
381 * Check out the runtime services table. We need to map
382 * the runtime services table so that we can grab the physical
383 * address of several of the EFI runtime functions, needed to
384 * set the firmware into virtual mode.
386 * When EFI_PARAVIRT is in force then we could not map runtime
387 * service memory region because we do not have direct access to it.
388 * However, runtime services are available through proxy functions
389 * (e.g. in case of Xen dom0 EFI implementation they call special
390 * hypercall which executes relevant EFI functions) and that is why
391 * they are always enabled.
394 if (!efi_enabled(EFI_PARAVIRT
)) {
395 if (efi_enabled(EFI_64BIT
))
396 rv
= efi_runtime_init64();
398 rv
= efi_runtime_init32();
404 set_bit(EFI_RUNTIME_SERVICES
, &efi
.flags
);
409 static int __init
efi_memmap_init(void)
411 if (efi_enabled(EFI_PARAVIRT
))
414 /* Map the EFI memory map */
415 memmap
.map
= early_memremap((unsigned long)memmap
.phys_map
,
416 memmap
.nr_map
* memmap
.desc_size
);
417 if (memmap
.map
== NULL
) {
418 pr_err("Could not map the memory map!\n");
421 memmap
.map_end
= memmap
.map
+ (memmap
.nr_map
* memmap
.desc_size
);
426 set_bit(EFI_MEMMAP
, &efi
.flags
);
431 void __init
efi_init(void)
434 char vendor
[100] = "unknown";
439 if (boot_params
.efi_info
.efi_systab_hi
||
440 boot_params
.efi_info
.efi_memmap_hi
) {
441 pr_info("Table located above 4GB, disabling EFI.\n");
444 efi_phys
.systab
= (efi_system_table_t
*)boot_params
.efi_info
.efi_systab
;
446 efi_phys
.systab
= (efi_system_table_t
*)
447 (boot_params
.efi_info
.efi_systab
|
448 ((__u64
)boot_params
.efi_info
.efi_systab_hi
<<32));
451 if (efi_systab_init(efi_phys
.systab
))
454 efi
.config_table
= (unsigned long)efi
.systab
->tables
;
455 efi
.fw_vendor
= (unsigned long)efi
.systab
->fw_vendor
;
456 efi
.runtime
= (unsigned long)efi
.systab
->runtime
;
459 * Show what we know for posterity
461 c16
= tmp
= early_memremap(efi
.systab
->fw_vendor
, 2);
463 for (i
= 0; i
< sizeof(vendor
) - 1 && *c16
; ++i
)
467 pr_err("Could not map the firmware vendor!\n");
468 early_memunmap(tmp
, 2);
470 pr_info("EFI v%u.%.02u by %s\n",
471 efi
.systab
->hdr
.revision
>> 16,
472 efi
.systab
->hdr
.revision
& 0xffff, vendor
);
474 if (efi_reuse_config(efi
.systab
->tables
, efi
.systab
->nr_tables
))
477 if (efi_config_init(arch_tables
))
481 * Note: We currently don't support runtime services on an EFI
482 * that doesn't match the kernel 32/64-bit mode.
485 if (!efi_runtime_supported())
486 pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
488 if (efi_runtime_disabled() || efi_runtime_init())
491 if (efi_memmap_init())
497 void __init
efi_late_init(void)
502 void __init
efi_set_executable(efi_memory_desc_t
*md
, bool executable
)
506 addr
= md
->virt_addr
;
507 npages
= md
->num_pages
;
509 memrange_efi_to_native(&addr
, &npages
);
512 set_memory_x(addr
, npages
);
514 set_memory_nx(addr
, npages
);
517 void __init
runtime_code_page_mkexec(void)
519 efi_memory_desc_t
*md
;
522 /* Make EFI runtime service code area executable */
523 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
526 if (md
->type
!= EFI_RUNTIME_SERVICES_CODE
)
529 efi_set_executable(md
, true);
533 void __init
efi_memory_uc(u64 addr
, unsigned long size
)
535 unsigned long page_shift
= 1UL << EFI_PAGE_SHIFT
;
538 npages
= round_up(size
, page_shift
) / page_shift
;
539 memrange_efi_to_native(&addr
, &npages
);
540 set_memory_uc(addr
, npages
);
543 void __init
old_map_region(efi_memory_desc_t
*md
)
545 u64 start_pfn
, end_pfn
, end
;
549 start_pfn
= PFN_DOWN(md
->phys_addr
);
550 size
= md
->num_pages
<< PAGE_SHIFT
;
551 end
= md
->phys_addr
+ size
;
552 end_pfn
= PFN_UP(end
);
554 if (pfn_range_is_mapped(start_pfn
, end_pfn
)) {
555 va
= __va(md
->phys_addr
);
557 if (!(md
->attribute
& EFI_MEMORY_WB
))
558 efi_memory_uc((u64
)(unsigned long)va
, size
);
560 va
= efi_ioremap(md
->phys_addr
, size
,
561 md
->type
, md
->attribute
);
563 md
->virt_addr
= (u64
) (unsigned long) va
;
565 pr_err("ioremap of 0x%llX failed!\n",
566 (unsigned long long)md
->phys_addr
);
569 /* Merge contiguous regions of the same type and attribute */
570 static void __init
efi_merge_regions(void)
573 efi_memory_desc_t
*md
, *prev_md
= NULL
;
575 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
584 if (prev_md
->type
!= md
->type
||
585 prev_md
->attribute
!= md
->attribute
) {
590 prev_size
= prev_md
->num_pages
<< EFI_PAGE_SHIFT
;
592 if (md
->phys_addr
== (prev_md
->phys_addr
+ prev_size
)) {
593 prev_md
->num_pages
+= md
->num_pages
;
594 md
->type
= EFI_RESERVED_TYPE
;
602 static void __init
get_systab_virt_addr(efi_memory_desc_t
*md
)
607 size
= md
->num_pages
<< EFI_PAGE_SHIFT
;
608 end
= md
->phys_addr
+ size
;
609 systab
= (u64
)(unsigned long)efi_phys
.systab
;
610 if (md
->phys_addr
<= systab
&& systab
< end
) {
611 systab
+= md
->virt_addr
- md
->phys_addr
;
612 efi
.systab
= (efi_system_table_t
*)(unsigned long)systab
;
616 static void __init
save_runtime_map(void)
619 efi_memory_desc_t
*md
;
620 void *tmp
, *p
, *q
= NULL
;
623 if (efi_enabled(EFI_OLD_MEMMAP
))
626 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
629 if (!(md
->attribute
& EFI_MEMORY_RUNTIME
) ||
630 (md
->type
== EFI_BOOT_SERVICES_CODE
) ||
631 (md
->type
== EFI_BOOT_SERVICES_DATA
))
633 tmp
= krealloc(q
, (count
+ 1) * memmap
.desc_size
, GFP_KERNEL
);
638 memcpy(q
+ count
* memmap
.desc_size
, md
, memmap
.desc_size
);
642 efi_runtime_map_setup(q
, count
, memmap
.desc_size
);
647 pr_err("Error saving runtime map, efi runtime on kexec non-functional!!\n");
651 static void *realloc_pages(void *old_memmap
, int old_shift
)
655 ret
= (void *)__get_free_pages(GFP_KERNEL
, old_shift
+ 1);
660 * A first-time allocation doesn't have anything to copy.
665 memcpy(ret
, old_memmap
, PAGE_SIZE
<< old_shift
);
668 free_pages((unsigned long)old_memmap
, old_shift
);
673 * Map the efi memory ranges of the runtime services and update new_mmap with
676 static void * __init
efi_map_regions(int *count
, int *pg_shift
)
678 void *p
, *new_memmap
= NULL
;
679 unsigned long left
= 0;
680 efi_memory_desc_t
*md
;
682 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
684 if (!(md
->attribute
& EFI_MEMORY_RUNTIME
)) {
686 if (md
->type
!= EFI_BOOT_SERVICES_CODE
&&
687 md
->type
!= EFI_BOOT_SERVICES_DATA
)
693 get_systab_virt_addr(md
);
695 if (left
< memmap
.desc_size
) {
696 new_memmap
= realloc_pages(new_memmap
, *pg_shift
);
700 left
+= PAGE_SIZE
<< *pg_shift
;
704 memcpy(new_memmap
+ (*count
* memmap
.desc_size
), md
,
707 left
-= memmap
.desc_size
;
714 static void __init
kexec_enter_virtual_mode(void)
717 efi_memory_desc_t
*md
;
723 * We don't do virtual mode, since we don't do runtime services, on
726 if (!efi_is_native()) {
728 clear_bit(EFI_RUNTIME_SERVICES
, &efi
.flags
);
733 * Map efi regions which were passed via setup_data. The virt_addr is a
734 * fixed addr which was used in first kernel of a kexec boot.
736 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
738 efi_map_region_fixed(md
); /* FIXME: add error handling */
739 get_systab_virt_addr(md
);
746 efi_sync_low_kernel_mappings();
749 * Now that EFI is in virtual mode, update the function
750 * pointers in the runtime service table to the new virtual addresses.
752 * Call EFI services through wrapper functions.
754 efi
.runtime_version
= efi_systab
.hdr
.revision
;
756 efi_native_runtime_setup();
758 efi
.set_virtual_address_map
= NULL
;
760 if (efi_enabled(EFI_OLD_MEMMAP
) && (__supported_pte_mask
& _PAGE_NX
))
761 runtime_code_page_mkexec();
763 /* clean DUMMY object */
764 efi_delete_dummy_variable();
769 * This function will switch the EFI runtime services to virtual mode.
770 * Essentially, we look through the EFI memmap and map every region that
771 * has the runtime attribute bit set in its memory descriptor into the
772 * ->trampoline_pgd page table using a top-down VA allocation scheme.
774 * The old method which used to update that memory descriptor with the
775 * virtual address obtained from ioremap() is still supported when the
776 * kernel is booted with efi=old_map on its command line. Same old
777 * method enabled the runtime services to be called without having to
778 * thunk back into physical mode for every invocation.
780 * The new method does a pagetable switch in a preemption-safe manner
781 * so that we're in a different address space when calling a runtime
782 * function. For function arguments passing we do copy the PGDs of the
783 * kernel page table into ->trampoline_pgd prior to each call.
785 * Specially for kexec boot, efi runtime maps in previous kernel should
786 * be passed in via setup_data. In that case runtime ranges will be mapped
787 * to the same virtual addresses as the first kernel, see
788 * kexec_enter_virtual_mode().
790 static void __init
__efi_enter_virtual_mode(void)
792 int count
= 0, pg_shift
= 0;
793 void *new_memmap
= NULL
;
799 new_memmap
= efi_map_regions(&count
, &pg_shift
);
801 pr_err("Error reallocating memory, EFI runtime non-functional!\n");
802 clear_bit(EFI_RUNTIME_SERVICES
, &efi
.flags
);
810 if (efi_setup_page_tables(__pa(new_memmap
), 1 << pg_shift
)) {
811 clear_bit(EFI_RUNTIME_SERVICES
, &efi
.flags
);
815 efi_sync_low_kernel_mappings();
816 efi_dump_pagetable();
818 if (efi_is_native()) {
819 status
= phys_efi_set_virtual_address_map(
820 memmap
.desc_size
* count
,
823 (efi_memory_desc_t
*)__pa(new_memmap
));
825 status
= efi_thunk_set_virtual_address_map(
826 efi_phys
.set_virtual_address_map
,
827 memmap
.desc_size
* count
,
830 (efi_memory_desc_t
*)__pa(new_memmap
));
833 if (status
!= EFI_SUCCESS
) {
834 pr_alert("Unable to switch EFI into virtual mode (status=%lx)!\n",
836 panic("EFI call to SetVirtualAddressMap() failed!");
840 * Now that EFI is in virtual mode, update the function
841 * pointers in the runtime service table to the new virtual addresses.
843 * Call EFI services through wrapper functions.
845 efi
.runtime_version
= efi_systab
.hdr
.revision
;
848 efi_native_runtime_setup();
850 efi_thunk_runtime_setup();
852 efi
.set_virtual_address_map
= NULL
;
854 efi_runtime_mkexec();
857 * We mapped the descriptor array into the EFI pagetable above but we're
858 * not unmapping it here. Here's why:
860 * We're copying select PGDs from the kernel page table to the EFI page
861 * table and when we do so and make changes to those PGDs like unmapping
862 * stuff from them, those changes appear in the kernel page table and we
865 * From setup_real_mode():
868 * trampoline_pgd[0] = init_level4_pgt[pgd_index(__PAGE_OFFSET)].pgd;
870 * In this particular case, our allocation is in PGD 0 of the EFI page
871 * table but we've copied that PGD from PGD[272] of the EFI page table:
873 * pgd_index(__PAGE_OFFSET = 0xffff880000000000) = 272
875 * where the direct memory mapping in kernel space is.
877 * new_memmap's VA comes from that direct mapping and thus clearing it,
878 * it would get cleared in the kernel page table too.
880 * efi_cleanup_page_tables(__pa(new_memmap), 1 << pg_shift);
882 free_pages((unsigned long)new_memmap
, pg_shift
);
884 /* clean DUMMY object */
885 efi_delete_dummy_variable();
888 void __init
efi_enter_virtual_mode(void)
890 if (efi_enabled(EFI_PARAVIRT
))
894 kexec_enter_virtual_mode();
896 __efi_enter_virtual_mode();
900 * Convenience functions to obtain memory types and attributes
902 u32
efi_mem_type(unsigned long phys_addr
)
904 efi_memory_desc_t
*md
;
907 if (!efi_enabled(EFI_MEMMAP
))
910 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
912 if ((md
->phys_addr
<= phys_addr
) &&
913 (phys_addr
< (md
->phys_addr
+
914 (md
->num_pages
<< EFI_PAGE_SHIFT
))))
920 u64
efi_mem_attributes(unsigned long phys_addr
)
922 efi_memory_desc_t
*md
;
925 if (!efi_enabled(EFI_MEMMAP
))
928 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
930 if ((md
->phys_addr
<= phys_addr
) &&
931 (phys_addr
< (md
->phys_addr
+
932 (md
->num_pages
<< EFI_PAGE_SHIFT
))))
933 return md
->attribute
;
938 static int __init
arch_parse_efi_cmdline(char *str
)
940 if (parse_option_str(str
, "old_map"))
941 set_bit(EFI_OLD_MEMMAP
, &efi
.flags
);
945 early_param("efi", arch_parse_efi_cmdline
);