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 bool disable_runtime __initdata
= false;
74 static int __init
setup_noefi(char *arg
)
76 disable_runtime
= true;
79 early_param("noefi", setup_noefi
);
82 EXPORT_SYMBOL(add_efi_memmap
);
84 static int __init
setup_add_efi_memmap(char *arg
)
89 early_param("add_efi_memmap", setup_add_efi_memmap
);
91 static efi_status_t __init
phys_efi_set_virtual_address_map(
92 unsigned long memory_map_size
,
93 unsigned long descriptor_size
,
94 u32 descriptor_version
,
95 efi_memory_desc_t
*virtual_map
)
99 efi_call_phys_prelog();
100 status
= efi_call_phys(efi_phys
.set_virtual_address_map
,
101 memory_map_size
, descriptor_size
,
102 descriptor_version
, virtual_map
);
103 efi_call_phys_epilog();
107 int efi_set_rtc_mmss(const struct timespec
*now
)
109 unsigned long nowtime
= now
->tv_sec
;
115 status
= efi
.get_time(&eft
, &cap
);
116 if (status
!= EFI_SUCCESS
) {
117 pr_err("Oops: efitime: can't read time!\n");
121 rtc_time_to_tm(nowtime
, &tm
);
122 if (!rtc_valid_tm(&tm
)) {
123 eft
.year
= tm
.tm_year
+ 1900;
124 eft
.month
= tm
.tm_mon
+ 1;
125 eft
.day
= tm
.tm_mday
;
126 eft
.minute
= tm
.tm_min
;
127 eft
.second
= tm
.tm_sec
;
130 pr_err("%s: Invalid EFI RTC value: write of %lx to EFI RTC failed\n",
135 status
= efi
.set_time(&eft
);
136 if (status
!= EFI_SUCCESS
) {
137 pr_err("Oops: efitime: can't write time!\n");
143 void efi_get_time(struct timespec
*now
)
149 status
= efi
.get_time(&eft
, &cap
);
150 if (status
!= EFI_SUCCESS
)
151 pr_err("Oops: efitime: can't read time!\n");
153 now
->tv_sec
= mktime(eft
.year
, eft
.month
, eft
.day
, eft
.hour
,
154 eft
.minute
, eft
.second
);
159 * Tell the kernel about the EFI memory map. This might include
160 * more than the max 128 entries that can fit in the e820 legacy
161 * (zeropage) memory map.
164 static void __init
do_add_efi_memmap(void)
168 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
169 efi_memory_desc_t
*md
= p
;
170 unsigned long long start
= md
->phys_addr
;
171 unsigned long long size
= md
->num_pages
<< EFI_PAGE_SHIFT
;
175 case EFI_LOADER_CODE
:
176 case EFI_LOADER_DATA
:
177 case EFI_BOOT_SERVICES_CODE
:
178 case EFI_BOOT_SERVICES_DATA
:
179 case EFI_CONVENTIONAL_MEMORY
:
180 if (md
->attribute
& EFI_MEMORY_WB
)
181 e820_type
= E820_RAM
;
183 e820_type
= E820_RESERVED
;
185 case EFI_ACPI_RECLAIM_MEMORY
:
186 e820_type
= E820_ACPI
;
188 case EFI_ACPI_MEMORY_NVS
:
189 e820_type
= E820_NVS
;
191 case EFI_UNUSABLE_MEMORY
:
192 e820_type
= E820_UNUSABLE
;
196 * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
197 * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
198 * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
200 e820_type
= E820_RESERVED
;
203 e820_add_region(start
, size
, e820_type
);
205 sanitize_e820_map(e820
.map
, ARRAY_SIZE(e820
.map
), &e820
.nr_map
);
208 int __init
efi_memblock_x86_reserve_range(void)
210 struct efi_info
*e
= &boot_params
.efi_info
;
213 if (efi_enabled(EFI_PARAVIRT
))
217 /* Can't handle data above 4GB at this time */
218 if (e
->efi_memmap_hi
) {
219 pr_err("Memory map is above 4GB, disabling EFI.\n");
222 pmap
= e
->efi_memmap
;
224 pmap
= (e
->efi_memmap
| ((__u64
)e
->efi_memmap_hi
<< 32));
226 memmap
.phys_map
= (void *)pmap
;
227 memmap
.nr_map
= e
->efi_memmap_size
/
229 memmap
.desc_size
= e
->efi_memdesc_size
;
230 memmap
.desc_version
= e
->efi_memdesc_version
;
232 memblock_reserve(pmap
, memmap
.nr_map
* memmap
.desc_size
);
234 efi
.memmap
= &memmap
;
239 static void __init
print_efi_memmap(void)
242 efi_memory_desc_t
*md
;
246 for (p
= memmap
.map
, i
= 0;
248 p
+= memmap
.desc_size
, i
++) {
250 pr_info("mem%02u: type=%u, attr=0x%llx, range=[0x%016llx-0x%016llx) (%lluMB)\n",
251 i
, md
->type
, md
->attribute
, md
->phys_addr
,
252 md
->phys_addr
+ (md
->num_pages
<< EFI_PAGE_SHIFT
),
253 (md
->num_pages
>> (20 - EFI_PAGE_SHIFT
)));
255 #endif /* EFI_DEBUG */
258 void __init
efi_unmap_memmap(void)
260 clear_bit(EFI_MEMMAP
, &efi
.flags
);
262 early_memunmap(memmap
.map
, memmap
.nr_map
* memmap
.desc_size
);
267 static int __init
efi_systab_init(void *phys
)
269 if (efi_enabled(EFI_64BIT
)) {
270 efi_system_table_64_t
*systab64
;
271 struct efi_setup_data
*data
= NULL
;
275 data
= early_memremap(efi_setup
, sizeof(*data
));
279 systab64
= early_memremap((unsigned long)phys
,
281 if (systab64
== NULL
) {
282 pr_err("Couldn't map the system table!\n");
284 early_memunmap(data
, sizeof(*data
));
288 efi_systab
.hdr
= systab64
->hdr
;
289 efi_systab
.fw_vendor
= data
? (unsigned long)data
->fw_vendor
:
291 tmp
|= data
? data
->fw_vendor
: systab64
->fw_vendor
;
292 efi_systab
.fw_revision
= systab64
->fw_revision
;
293 efi_systab
.con_in_handle
= systab64
->con_in_handle
;
294 tmp
|= systab64
->con_in_handle
;
295 efi_systab
.con_in
= systab64
->con_in
;
296 tmp
|= systab64
->con_in
;
297 efi_systab
.con_out_handle
= systab64
->con_out_handle
;
298 tmp
|= systab64
->con_out_handle
;
299 efi_systab
.con_out
= systab64
->con_out
;
300 tmp
|= systab64
->con_out
;
301 efi_systab
.stderr_handle
= systab64
->stderr_handle
;
302 tmp
|= systab64
->stderr_handle
;
303 efi_systab
.stderr
= systab64
->stderr
;
304 tmp
|= systab64
->stderr
;
305 efi_systab
.runtime
= data
?
306 (void *)(unsigned long)data
->runtime
:
307 (void *)(unsigned long)systab64
->runtime
;
308 tmp
|= data
? data
->runtime
: systab64
->runtime
;
309 efi_systab
.boottime
= (void *)(unsigned long)systab64
->boottime
;
310 tmp
|= systab64
->boottime
;
311 efi_systab
.nr_tables
= systab64
->nr_tables
;
312 efi_systab
.tables
= data
? (unsigned long)data
->tables
:
314 tmp
|= data
? data
->tables
: systab64
->tables
;
316 early_memunmap(systab64
, sizeof(*systab64
));
318 early_memunmap(data
, sizeof(*data
));
321 pr_err("EFI data located above 4GB, disabling EFI.\n");
326 efi_system_table_32_t
*systab32
;
328 systab32
= early_memremap((unsigned long)phys
,
330 if (systab32
== NULL
) {
331 pr_err("Couldn't map the system table!\n");
335 efi_systab
.hdr
= systab32
->hdr
;
336 efi_systab
.fw_vendor
= systab32
->fw_vendor
;
337 efi_systab
.fw_revision
= systab32
->fw_revision
;
338 efi_systab
.con_in_handle
= systab32
->con_in_handle
;
339 efi_systab
.con_in
= systab32
->con_in
;
340 efi_systab
.con_out_handle
= systab32
->con_out_handle
;
341 efi_systab
.con_out
= systab32
->con_out
;
342 efi_systab
.stderr_handle
= systab32
->stderr_handle
;
343 efi_systab
.stderr
= systab32
->stderr
;
344 efi_systab
.runtime
= (void *)(unsigned long)systab32
->runtime
;
345 efi_systab
.boottime
= (void *)(unsigned long)systab32
->boottime
;
346 efi_systab
.nr_tables
= systab32
->nr_tables
;
347 efi_systab
.tables
= systab32
->tables
;
349 early_memunmap(systab32
, sizeof(*systab32
));
352 efi
.systab
= &efi_systab
;
355 * Verify the EFI Table
357 if (efi
.systab
->hdr
.signature
!= EFI_SYSTEM_TABLE_SIGNATURE
) {
358 pr_err("System table signature incorrect!\n");
361 if ((efi
.systab
->hdr
.revision
>> 16) == 0)
362 pr_err("Warning: System table version %d.%02d, expected 1.00 or greater!\n",
363 efi
.systab
->hdr
.revision
>> 16,
364 efi
.systab
->hdr
.revision
& 0xffff);
366 set_bit(EFI_SYSTEM_TABLES
, &efi
.flags
);
371 static int __init
efi_runtime_init32(void)
373 efi_runtime_services_32_t
*runtime
;
375 runtime
= early_memremap((unsigned long)efi
.systab
->runtime
,
376 sizeof(efi_runtime_services_32_t
));
378 pr_err("Could not map the runtime service table!\n");
383 * We will only need *early* access to the following two
384 * EFI runtime services before set_virtual_address_map
387 efi_phys
.set_virtual_address_map
=
388 (efi_set_virtual_address_map_t
*)
389 (unsigned long)runtime
->set_virtual_address_map
;
390 early_memunmap(runtime
, sizeof(efi_runtime_services_32_t
));
395 static int __init
efi_runtime_init64(void)
397 efi_runtime_services_64_t
*runtime
;
399 runtime
= early_memremap((unsigned long)efi
.systab
->runtime
,
400 sizeof(efi_runtime_services_64_t
));
402 pr_err("Could not map the runtime service table!\n");
407 * We will only need *early* access to the following two
408 * EFI runtime services before set_virtual_address_map
411 efi_phys
.set_virtual_address_map
=
412 (efi_set_virtual_address_map_t
*)
413 (unsigned long)runtime
->set_virtual_address_map
;
414 early_memunmap(runtime
, sizeof(efi_runtime_services_64_t
));
419 static int __init
efi_runtime_init(void)
424 * Check out the runtime services table. We need to map
425 * the runtime services table so that we can grab the physical
426 * address of several of the EFI runtime functions, needed to
427 * set the firmware into virtual mode.
429 * When EFI_PARAVIRT is in force then we could not map runtime
430 * service memory region because we do not have direct access to it.
431 * However, runtime services are available through proxy functions
432 * (e.g. in case of Xen dom0 EFI implementation they call special
433 * hypercall which executes relevant EFI functions) and that is why
434 * they are always enabled.
437 if (!efi_enabled(EFI_PARAVIRT
)) {
438 if (efi_enabled(EFI_64BIT
))
439 rv
= efi_runtime_init64();
441 rv
= efi_runtime_init32();
447 set_bit(EFI_RUNTIME_SERVICES
, &efi
.flags
);
452 static int __init
efi_memmap_init(void)
454 if (efi_enabled(EFI_PARAVIRT
))
457 /* Map the EFI memory map */
458 memmap
.map
= early_memremap((unsigned long)memmap
.phys_map
,
459 memmap
.nr_map
* memmap
.desc_size
);
460 if (memmap
.map
== NULL
) {
461 pr_err("Could not map the memory map!\n");
464 memmap
.map_end
= memmap
.map
+ (memmap
.nr_map
* memmap
.desc_size
);
469 set_bit(EFI_MEMMAP
, &efi
.flags
);
474 void __init
efi_init(void)
477 char vendor
[100] = "unknown";
482 if (boot_params
.efi_info
.efi_systab_hi
||
483 boot_params
.efi_info
.efi_memmap_hi
) {
484 pr_info("Table located above 4GB, disabling EFI.\n");
487 efi_phys
.systab
= (efi_system_table_t
*)boot_params
.efi_info
.efi_systab
;
489 efi_phys
.systab
= (efi_system_table_t
*)
490 (boot_params
.efi_info
.efi_systab
|
491 ((__u64
)boot_params
.efi_info
.efi_systab_hi
<<32));
494 if (efi_systab_init(efi_phys
.systab
))
497 efi
.config_table
= (unsigned long)efi
.systab
->tables
;
498 efi
.fw_vendor
= (unsigned long)efi
.systab
->fw_vendor
;
499 efi
.runtime
= (unsigned long)efi
.systab
->runtime
;
502 * Show what we know for posterity
504 c16
= tmp
= early_memremap(efi
.systab
->fw_vendor
, 2);
506 for (i
= 0; i
< sizeof(vendor
) - 1 && *c16
; ++i
)
510 pr_err("Could not map the firmware vendor!\n");
511 early_memunmap(tmp
, 2);
513 pr_info("EFI v%u.%.02u by %s\n",
514 efi
.systab
->hdr
.revision
>> 16,
515 efi
.systab
->hdr
.revision
& 0xffff, vendor
);
517 if (efi_reuse_config(efi
.systab
->tables
, efi
.systab
->nr_tables
))
520 if (efi_config_init(arch_tables
))
524 * Note: We currently don't support runtime services on an EFI
525 * that doesn't match the kernel 32/64-bit mode.
528 if (!efi_runtime_supported())
529 pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
531 if (disable_runtime
|| efi_runtime_init())
534 if (efi_memmap_init())
537 set_bit(EFI_MEMMAP
, &efi
.flags
);
542 void __init
efi_late_init(void)
547 void __init
efi_set_executable(efi_memory_desc_t
*md
, bool executable
)
551 addr
= md
->virt_addr
;
552 npages
= md
->num_pages
;
554 memrange_efi_to_native(&addr
, &npages
);
557 set_memory_x(addr
, npages
);
559 set_memory_nx(addr
, npages
);
562 void __init
runtime_code_page_mkexec(void)
564 efi_memory_desc_t
*md
;
567 /* Make EFI runtime service code area executable */
568 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
571 if (md
->type
!= EFI_RUNTIME_SERVICES_CODE
)
574 efi_set_executable(md
, true);
578 void efi_memory_uc(u64 addr
, unsigned long size
)
580 unsigned long page_shift
= 1UL << EFI_PAGE_SHIFT
;
583 npages
= round_up(size
, page_shift
) / page_shift
;
584 memrange_efi_to_native(&addr
, &npages
);
585 set_memory_uc(addr
, npages
);
588 void __init
old_map_region(efi_memory_desc_t
*md
)
590 u64 start_pfn
, end_pfn
, end
;
594 start_pfn
= PFN_DOWN(md
->phys_addr
);
595 size
= md
->num_pages
<< PAGE_SHIFT
;
596 end
= md
->phys_addr
+ size
;
597 end_pfn
= PFN_UP(end
);
599 if (pfn_range_is_mapped(start_pfn
, end_pfn
)) {
600 va
= __va(md
->phys_addr
);
602 if (!(md
->attribute
& EFI_MEMORY_WB
))
603 efi_memory_uc((u64
)(unsigned long)va
, size
);
605 va
= efi_ioremap(md
->phys_addr
, size
,
606 md
->type
, md
->attribute
);
608 md
->virt_addr
= (u64
) (unsigned long) va
;
610 pr_err("ioremap of 0x%llX failed!\n",
611 (unsigned long long)md
->phys_addr
);
614 /* Merge contiguous regions of the same type and attribute */
615 static void __init
efi_merge_regions(void)
618 efi_memory_desc_t
*md
, *prev_md
= NULL
;
620 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
629 if (prev_md
->type
!= md
->type
||
630 prev_md
->attribute
!= md
->attribute
) {
635 prev_size
= prev_md
->num_pages
<< EFI_PAGE_SHIFT
;
637 if (md
->phys_addr
== (prev_md
->phys_addr
+ prev_size
)) {
638 prev_md
->num_pages
+= md
->num_pages
;
639 md
->type
= EFI_RESERVED_TYPE
;
647 static void __init
get_systab_virt_addr(efi_memory_desc_t
*md
)
652 size
= md
->num_pages
<< EFI_PAGE_SHIFT
;
653 end
= md
->phys_addr
+ size
;
654 systab
= (u64
)(unsigned long)efi_phys
.systab
;
655 if (md
->phys_addr
<= systab
&& systab
< end
) {
656 systab
+= md
->virt_addr
- md
->phys_addr
;
657 efi
.systab
= (efi_system_table_t
*)(unsigned long)systab
;
661 static void __init
save_runtime_map(void)
664 efi_memory_desc_t
*md
;
665 void *tmp
, *p
, *q
= NULL
;
668 if (efi_enabled(EFI_OLD_MEMMAP
))
671 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
674 if (!(md
->attribute
& EFI_MEMORY_RUNTIME
) ||
675 (md
->type
== EFI_BOOT_SERVICES_CODE
) ||
676 (md
->type
== EFI_BOOT_SERVICES_DATA
))
678 tmp
= krealloc(q
, (count
+ 1) * memmap
.desc_size
, GFP_KERNEL
);
683 memcpy(q
+ count
* memmap
.desc_size
, md
, memmap
.desc_size
);
687 efi_runtime_map_setup(q
, count
, memmap
.desc_size
);
692 pr_err("Error saving runtime map, efi runtime on kexec non-functional!!\n");
696 static void *realloc_pages(void *old_memmap
, int old_shift
)
700 ret
= (void *)__get_free_pages(GFP_KERNEL
, old_shift
+ 1);
705 * A first-time allocation doesn't have anything to copy.
710 memcpy(ret
, old_memmap
, PAGE_SIZE
<< old_shift
);
713 free_pages((unsigned long)old_memmap
, old_shift
);
718 * Map the efi memory ranges of the runtime services and update new_mmap with
721 static void * __init
efi_map_regions(int *count
, int *pg_shift
)
723 void *p
, *new_memmap
= NULL
;
724 unsigned long left
= 0;
725 efi_memory_desc_t
*md
;
727 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
729 if (!(md
->attribute
& EFI_MEMORY_RUNTIME
)) {
731 if (md
->type
!= EFI_BOOT_SERVICES_CODE
&&
732 md
->type
!= EFI_BOOT_SERVICES_DATA
)
738 get_systab_virt_addr(md
);
740 if (left
< memmap
.desc_size
) {
741 new_memmap
= realloc_pages(new_memmap
, *pg_shift
);
745 left
+= PAGE_SIZE
<< *pg_shift
;
749 memcpy(new_memmap
+ (*count
* memmap
.desc_size
), md
,
752 left
-= memmap
.desc_size
;
759 static void __init
kexec_enter_virtual_mode(void)
762 efi_memory_desc_t
*md
;
768 * We don't do virtual mode, since we don't do runtime services, on
771 if (!efi_is_native()) {
777 * Map efi regions which were passed via setup_data. The virt_addr is a
778 * fixed addr which was used in first kernel of a kexec boot.
780 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
782 efi_map_region_fixed(md
); /* FIXME: add error handling */
783 get_systab_virt_addr(md
);
790 efi_sync_low_kernel_mappings();
793 * Now that EFI is in virtual mode, update the function
794 * pointers in the runtime service table to the new virtual addresses.
796 * Call EFI services through wrapper functions.
798 efi
.runtime_version
= efi_systab
.hdr
.revision
;
800 efi_native_runtime_setup();
802 efi
.set_virtual_address_map
= NULL
;
804 if (efi_enabled(EFI_OLD_MEMMAP
) && (__supported_pte_mask
& _PAGE_NX
))
805 runtime_code_page_mkexec();
807 /* clean DUMMY object */
808 efi_delete_dummy_variable();
813 * This function will switch the EFI runtime services to virtual mode.
814 * Essentially, we look through the EFI memmap and map every region that
815 * has the runtime attribute bit set in its memory descriptor into the
816 * ->trampoline_pgd page table using a top-down VA allocation scheme.
818 * The old method which used to update that memory descriptor with the
819 * virtual address obtained from ioremap() is still supported when the
820 * kernel is booted with efi=old_map on its command line. Same old
821 * method enabled the runtime services to be called without having to
822 * thunk back into physical mode for every invocation.
824 * The new method does a pagetable switch in a preemption-safe manner
825 * so that we're in a different address space when calling a runtime
826 * function. For function arguments passing we do copy the PGDs of the
827 * kernel page table into ->trampoline_pgd prior to each call.
829 * Specially for kexec boot, efi runtime maps in previous kernel should
830 * be passed in via setup_data. In that case runtime ranges will be mapped
831 * to the same virtual addresses as the first kernel, see
832 * kexec_enter_virtual_mode().
834 static void __init
__efi_enter_virtual_mode(void)
836 int count
= 0, pg_shift
= 0;
837 void *new_memmap
= NULL
;
843 new_memmap
= efi_map_regions(&count
, &pg_shift
);
845 pr_err("Error reallocating memory, EFI runtime non-functional!\n");
853 if (efi_setup_page_tables(__pa(new_memmap
), 1 << pg_shift
))
856 efi_sync_low_kernel_mappings();
857 efi_dump_pagetable();
859 if (efi_is_native()) {
860 status
= phys_efi_set_virtual_address_map(
861 memmap
.desc_size
* count
,
864 (efi_memory_desc_t
*)__pa(new_memmap
));
866 status
= efi_thunk_set_virtual_address_map(
867 efi_phys
.set_virtual_address_map
,
868 memmap
.desc_size
* count
,
871 (efi_memory_desc_t
*)__pa(new_memmap
));
874 if (status
!= EFI_SUCCESS
) {
875 pr_alert("Unable to switch EFI into virtual mode (status=%lx)!\n",
877 panic("EFI call to SetVirtualAddressMap() failed!");
881 * Now that EFI is in virtual mode, update the function
882 * pointers in the runtime service table to the new virtual addresses.
884 * Call EFI services through wrapper functions.
886 efi
.runtime_version
= efi_systab
.hdr
.revision
;
889 efi_native_runtime_setup();
891 efi_thunk_runtime_setup();
893 efi
.set_virtual_address_map
= NULL
;
895 efi_runtime_mkexec();
898 * We mapped the descriptor array into the EFI pagetable above but we're
899 * not unmapping it here. Here's why:
901 * We're copying select PGDs from the kernel page table to the EFI page
902 * table and when we do so and make changes to those PGDs like unmapping
903 * stuff from them, those changes appear in the kernel page table and we
906 * From setup_real_mode():
909 * trampoline_pgd[0] = init_level4_pgt[pgd_index(__PAGE_OFFSET)].pgd;
911 * In this particular case, our allocation is in PGD 0 of the EFI page
912 * table but we've copied that PGD from PGD[272] of the EFI page table:
914 * pgd_index(__PAGE_OFFSET = 0xffff880000000000) = 272
916 * where the direct memory mapping in kernel space is.
918 * new_memmap's VA comes from that direct mapping and thus clearing it,
919 * it would get cleared in the kernel page table too.
921 * efi_cleanup_page_tables(__pa(new_memmap), 1 << pg_shift);
923 free_pages((unsigned long)new_memmap
, pg_shift
);
925 /* clean DUMMY object */
926 efi_delete_dummy_variable();
929 void __init
efi_enter_virtual_mode(void)
931 if (efi_enabled(EFI_PARAVIRT
))
935 kexec_enter_virtual_mode();
937 __efi_enter_virtual_mode();
941 * Convenience functions to obtain memory types and attributes
943 u32
efi_mem_type(unsigned long phys_addr
)
945 efi_memory_desc_t
*md
;
948 if (!efi_enabled(EFI_MEMMAP
))
951 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
953 if ((md
->phys_addr
<= phys_addr
) &&
954 (phys_addr
< (md
->phys_addr
+
955 (md
->num_pages
<< EFI_PAGE_SHIFT
))))
961 u64
efi_mem_attributes(unsigned long phys_addr
)
963 efi_memory_desc_t
*md
;
966 if (!efi_enabled(EFI_MEMMAP
))
969 for (p
= memmap
.map
; p
< memmap
.map_end
; p
+= memmap
.desc_size
) {
971 if ((md
->phys_addr
<= phys_addr
) &&
972 (phys_addr
< (md
->phys_addr
+
973 (md
->num_pages
<< EFI_PAGE_SHIFT
))))
974 return md
->attribute
;
979 static int __init
parse_efi_cmdline(char *str
)
984 if (!strncmp(str
, "old_map", 7))
985 set_bit(EFI_OLD_MEMMAP
, &efi
.flags
);
989 early_param("efi", parse_efi_cmdline
);