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>
54 #include <asm/uv/uv.h>
56 static struct efi efi_phys __initdata
;
57 static efi_system_table_t efi_systab __initdata
;
59 static efi_config_table_type_t arch_tables
[] __initdata
= {
61 {UV_SYSTEM_TABLE_GUID
, "UVsystab", &efi
.uv_systab
},
63 {NULL_GUID
, NULL
, NULL
},
66 u64 efi_setup
; /* efi setup_data physical address */
68 static int add_efi_memmap __initdata
;
69 static int __init
setup_add_efi_memmap(char *arg
)
74 early_param("add_efi_memmap", setup_add_efi_memmap
);
76 static efi_status_t __init
phys_efi_set_virtual_address_map(
77 unsigned long memory_map_size
,
78 unsigned long descriptor_size
,
79 u32 descriptor_version
,
80 efi_memory_desc_t
*virtual_map
)
86 save_pgd
= efi_call_phys_prolog();
88 /* Disable interrupts around EFI calls: */
89 local_irq_save(flags
);
90 status
= efi_call_phys(efi_phys
.set_virtual_address_map
,
91 memory_map_size
, descriptor_size
,
92 descriptor_version
, virtual_map
);
93 local_irq_restore(flags
);
95 efi_call_phys_epilog(save_pgd
);
100 void __init
efi_find_mirror(void)
102 efi_memory_desc_t
*md
;
103 u64 mirror_size
= 0, total_size
= 0;
105 for_each_efi_memory_desc(md
) {
106 unsigned long long start
= md
->phys_addr
;
107 unsigned long long size
= md
->num_pages
<< EFI_PAGE_SHIFT
;
110 if (md
->attribute
& EFI_MEMORY_MORE_RELIABLE
) {
111 memblock_mark_mirror(start
, size
);
116 pr_info("Memory: %lldM/%lldM mirrored memory\n",
117 mirror_size
>>20, total_size
>>20);
121 * Tell the kernel about the EFI memory map. This might include
122 * more than the max 128 entries that can fit in the e820 legacy
123 * (zeropage) memory map.
126 static void __init
do_add_efi_memmap(void)
128 efi_memory_desc_t
*md
;
130 for_each_efi_memory_desc(md
) {
131 unsigned long long start
= md
->phys_addr
;
132 unsigned long long size
= md
->num_pages
<< EFI_PAGE_SHIFT
;
136 case EFI_LOADER_CODE
:
137 case EFI_LOADER_DATA
:
138 case EFI_BOOT_SERVICES_CODE
:
139 case EFI_BOOT_SERVICES_DATA
:
140 case EFI_CONVENTIONAL_MEMORY
:
141 if (md
->attribute
& EFI_MEMORY_WB
)
142 e820_type
= E820_RAM
;
144 e820_type
= E820_RESERVED
;
146 case EFI_ACPI_RECLAIM_MEMORY
:
147 e820_type
= E820_ACPI
;
149 case EFI_ACPI_MEMORY_NVS
:
150 e820_type
= E820_NVS
;
152 case EFI_UNUSABLE_MEMORY
:
153 e820_type
= E820_UNUSABLE
;
155 case EFI_PERSISTENT_MEMORY
:
156 e820_type
= E820_PMEM
;
160 * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
161 * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
162 * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
164 e820_type
= E820_RESERVED
;
167 e820_add_region(start
, size
, e820_type
);
169 sanitize_e820_map(e820
.map
, ARRAY_SIZE(e820
.map
), &e820
.nr_map
);
172 int __init
efi_memblock_x86_reserve_range(void)
174 struct efi_info
*e
= &boot_params
.efi_info
;
177 if (efi_enabled(EFI_PARAVIRT
))
181 /* Can't handle data above 4GB at this time */
182 if (e
->efi_memmap_hi
) {
183 pr_err("Memory map is above 4GB, disabling EFI.\n");
186 pmap
= e
->efi_memmap
;
188 pmap
= (e
->efi_memmap
| ((__u64
)e
->efi_memmap_hi
<< 32));
190 efi
.memmap
.phys_map
= pmap
;
191 efi
.memmap
.nr_map
= e
->efi_memmap_size
/
193 efi
.memmap
.desc_size
= e
->efi_memdesc_size
;
194 efi
.memmap
.desc_version
= e
->efi_memdesc_version
;
196 WARN(efi
.memmap
.desc_version
!= 1,
197 "Unexpected EFI_MEMORY_DESCRIPTOR version %ld",
198 efi
.memmap
.desc_version
);
200 memblock_reserve(pmap
, efi
.memmap
.nr_map
* efi
.memmap
.desc_size
);
205 void __init
efi_print_memmap(void)
207 efi_memory_desc_t
*md
;
210 for_each_efi_memory_desc(md
) {
213 pr_info("mem%02u: %s range=[0x%016llx-0x%016llx] (%lluMB)\n",
214 i
++, efi_md_typeattr_format(buf
, sizeof(buf
), md
),
216 md
->phys_addr
+ (md
->num_pages
<< EFI_PAGE_SHIFT
) - 1,
217 (md
->num_pages
>> (20 - EFI_PAGE_SHIFT
)));
221 void __init
efi_unmap_memmap(void)
225 clear_bit(EFI_MEMMAP
, &efi
.flags
);
227 size
= efi
.memmap
.nr_map
* efi
.memmap
.desc_size
;
228 if (efi
.memmap
.map
) {
229 early_memunmap(efi
.memmap
.map
, size
);
230 efi
.memmap
.map
= NULL
;
234 static int __init
efi_systab_init(void *phys
)
236 if (efi_enabled(EFI_64BIT
)) {
237 efi_system_table_64_t
*systab64
;
238 struct efi_setup_data
*data
= NULL
;
242 data
= early_memremap(efi_setup
, sizeof(*data
));
246 systab64
= early_memremap((unsigned long)phys
,
248 if (systab64
== NULL
) {
249 pr_err("Couldn't map the system table!\n");
251 early_memunmap(data
, sizeof(*data
));
255 efi_systab
.hdr
= systab64
->hdr
;
256 efi_systab
.fw_vendor
= data
? (unsigned long)data
->fw_vendor
:
258 tmp
|= data
? data
->fw_vendor
: systab64
->fw_vendor
;
259 efi_systab
.fw_revision
= systab64
->fw_revision
;
260 efi_systab
.con_in_handle
= systab64
->con_in_handle
;
261 tmp
|= systab64
->con_in_handle
;
262 efi_systab
.con_in
= systab64
->con_in
;
263 tmp
|= systab64
->con_in
;
264 efi_systab
.con_out_handle
= systab64
->con_out_handle
;
265 tmp
|= systab64
->con_out_handle
;
266 efi_systab
.con_out
= systab64
->con_out
;
267 tmp
|= systab64
->con_out
;
268 efi_systab
.stderr_handle
= systab64
->stderr_handle
;
269 tmp
|= systab64
->stderr_handle
;
270 efi_systab
.stderr
= systab64
->stderr
;
271 tmp
|= systab64
->stderr
;
272 efi_systab
.runtime
= data
?
273 (void *)(unsigned long)data
->runtime
:
274 (void *)(unsigned long)systab64
->runtime
;
275 tmp
|= data
? data
->runtime
: systab64
->runtime
;
276 efi_systab
.boottime
= (void *)(unsigned long)systab64
->boottime
;
277 tmp
|= systab64
->boottime
;
278 efi_systab
.nr_tables
= systab64
->nr_tables
;
279 efi_systab
.tables
= data
? (unsigned long)data
->tables
:
281 tmp
|= data
? data
->tables
: systab64
->tables
;
283 early_memunmap(systab64
, sizeof(*systab64
));
285 early_memunmap(data
, sizeof(*data
));
288 pr_err("EFI data located above 4GB, disabling EFI.\n");
293 efi_system_table_32_t
*systab32
;
295 systab32
= early_memremap((unsigned long)phys
,
297 if (systab32
== NULL
) {
298 pr_err("Couldn't map the system table!\n");
302 efi_systab
.hdr
= systab32
->hdr
;
303 efi_systab
.fw_vendor
= systab32
->fw_vendor
;
304 efi_systab
.fw_revision
= systab32
->fw_revision
;
305 efi_systab
.con_in_handle
= systab32
->con_in_handle
;
306 efi_systab
.con_in
= systab32
->con_in
;
307 efi_systab
.con_out_handle
= systab32
->con_out_handle
;
308 efi_systab
.con_out
= systab32
->con_out
;
309 efi_systab
.stderr_handle
= systab32
->stderr_handle
;
310 efi_systab
.stderr
= systab32
->stderr
;
311 efi_systab
.runtime
= (void *)(unsigned long)systab32
->runtime
;
312 efi_systab
.boottime
= (void *)(unsigned long)systab32
->boottime
;
313 efi_systab
.nr_tables
= systab32
->nr_tables
;
314 efi_systab
.tables
= systab32
->tables
;
316 early_memunmap(systab32
, sizeof(*systab32
));
319 efi
.systab
= &efi_systab
;
322 * Verify the EFI Table
324 if (efi
.systab
->hdr
.signature
!= EFI_SYSTEM_TABLE_SIGNATURE
) {
325 pr_err("System table signature incorrect!\n");
328 if ((efi
.systab
->hdr
.revision
>> 16) == 0)
329 pr_err("Warning: System table version %d.%02d, expected 1.00 or greater!\n",
330 efi
.systab
->hdr
.revision
>> 16,
331 efi
.systab
->hdr
.revision
& 0xffff);
336 static int __init
efi_runtime_init32(void)
338 efi_runtime_services_32_t
*runtime
;
340 runtime
= early_memremap((unsigned long)efi
.systab
->runtime
,
341 sizeof(efi_runtime_services_32_t
));
343 pr_err("Could not map the runtime service table!\n");
348 * We will only need *early* access to the SetVirtualAddressMap
349 * EFI runtime service. All other runtime services will be called
350 * via the virtual mapping.
352 efi_phys
.set_virtual_address_map
=
353 (efi_set_virtual_address_map_t
*)
354 (unsigned long)runtime
->set_virtual_address_map
;
355 early_memunmap(runtime
, sizeof(efi_runtime_services_32_t
));
360 static int __init
efi_runtime_init64(void)
362 efi_runtime_services_64_t
*runtime
;
364 runtime
= early_memremap((unsigned long)efi
.systab
->runtime
,
365 sizeof(efi_runtime_services_64_t
));
367 pr_err("Could not map the runtime service table!\n");
372 * We will only need *early* access to the SetVirtualAddressMap
373 * EFI runtime service. All other runtime services will be called
374 * via the virtual mapping.
376 efi_phys
.set_virtual_address_map
=
377 (efi_set_virtual_address_map_t
*)
378 (unsigned long)runtime
->set_virtual_address_map
;
379 early_memunmap(runtime
, sizeof(efi_runtime_services_64_t
));
384 static int __init
efi_runtime_init(void)
389 * Check out the runtime services table. We need to map
390 * the runtime services table so that we can grab the physical
391 * address of several of the EFI runtime functions, needed to
392 * set the firmware into virtual mode.
394 * When EFI_PARAVIRT is in force then we could not map runtime
395 * service memory region because we do not have direct access to it.
396 * However, runtime services are available through proxy functions
397 * (e.g. in case of Xen dom0 EFI implementation they call special
398 * hypercall which executes relevant EFI functions) and that is why
399 * they are always enabled.
402 if (!efi_enabled(EFI_PARAVIRT
)) {
403 if (efi_enabled(EFI_64BIT
))
404 rv
= efi_runtime_init64();
406 rv
= efi_runtime_init32();
412 set_bit(EFI_RUNTIME_SERVICES
, &efi
.flags
);
417 static int __init
efi_memmap_init(void)
419 unsigned long addr
, size
;
421 if (efi_enabled(EFI_PARAVIRT
))
424 /* Map the EFI memory map */
425 size
= efi
.memmap
.nr_map
* efi
.memmap
.desc_size
;
426 addr
= (unsigned long)efi
.memmap
.phys_map
;
428 efi
.memmap
.map
= early_memremap(addr
, size
);
429 if (efi
.memmap
.map
== NULL
) {
430 pr_err("Could not map the memory map!\n");
434 efi
.memmap
.map_end
= efi
.memmap
.map
+ size
;
439 set_bit(EFI_MEMMAP
, &efi
.flags
);
444 void __init
efi_init(void)
447 char vendor
[100] = "unknown";
452 if (boot_params
.efi_info
.efi_systab_hi
||
453 boot_params
.efi_info
.efi_memmap_hi
) {
454 pr_info("Table located above 4GB, disabling EFI.\n");
457 efi_phys
.systab
= (efi_system_table_t
*)boot_params
.efi_info
.efi_systab
;
459 efi_phys
.systab
= (efi_system_table_t
*)
460 (boot_params
.efi_info
.efi_systab
|
461 ((__u64
)boot_params
.efi_info
.efi_systab_hi
<<32));
464 if (efi_systab_init(efi_phys
.systab
))
467 efi
.config_table
= (unsigned long)efi
.systab
->tables
;
468 efi
.fw_vendor
= (unsigned long)efi
.systab
->fw_vendor
;
469 efi
.runtime
= (unsigned long)efi
.systab
->runtime
;
472 * Show what we know for posterity
474 c16
= tmp
= early_memremap(efi
.systab
->fw_vendor
, 2);
476 for (i
= 0; i
< sizeof(vendor
) - 1 && *c16
; ++i
)
480 pr_err("Could not map the firmware vendor!\n");
481 early_memunmap(tmp
, 2);
483 pr_info("EFI v%u.%.02u by %s\n",
484 efi
.systab
->hdr
.revision
>> 16,
485 efi
.systab
->hdr
.revision
& 0xffff, vendor
);
487 if (efi_reuse_config(efi
.systab
->tables
, efi
.systab
->nr_tables
))
490 if (efi_config_init(arch_tables
))
494 * Note: We currently don't support runtime services on an EFI
495 * that doesn't match the kernel 32/64-bit mode.
498 if (!efi_runtime_supported())
499 pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
501 if (efi_runtime_disabled() || efi_runtime_init())
504 if (efi_memmap_init())
507 if (efi_enabled(EFI_DBG
))
513 void __init
efi_late_init(void)
518 void __init
efi_set_executable(efi_memory_desc_t
*md
, bool executable
)
522 addr
= md
->virt_addr
;
523 npages
= md
->num_pages
;
525 memrange_efi_to_native(&addr
, &npages
);
528 set_memory_x(addr
, npages
);
530 set_memory_nx(addr
, npages
);
533 void __init
runtime_code_page_mkexec(void)
535 efi_memory_desc_t
*md
;
537 /* Make EFI runtime service code area executable */
538 for_each_efi_memory_desc(md
) {
539 if (md
->type
!= EFI_RUNTIME_SERVICES_CODE
)
542 efi_set_executable(md
, true);
546 void __init
efi_memory_uc(u64 addr
, unsigned long size
)
548 unsigned long page_shift
= 1UL << EFI_PAGE_SHIFT
;
551 npages
= round_up(size
, page_shift
) / page_shift
;
552 memrange_efi_to_native(&addr
, &npages
);
553 set_memory_uc(addr
, npages
);
556 void __init
old_map_region(efi_memory_desc_t
*md
)
558 u64 start_pfn
, end_pfn
, end
;
562 start_pfn
= PFN_DOWN(md
->phys_addr
);
563 size
= md
->num_pages
<< PAGE_SHIFT
;
564 end
= md
->phys_addr
+ size
;
565 end_pfn
= PFN_UP(end
);
567 if (pfn_range_is_mapped(start_pfn
, end_pfn
)) {
568 va
= __va(md
->phys_addr
);
570 if (!(md
->attribute
& EFI_MEMORY_WB
))
571 efi_memory_uc((u64
)(unsigned long)va
, size
);
573 va
= efi_ioremap(md
->phys_addr
, size
,
574 md
->type
, md
->attribute
);
576 md
->virt_addr
= (u64
) (unsigned long) va
;
578 pr_err("ioremap of 0x%llX failed!\n",
579 (unsigned long long)md
->phys_addr
);
582 /* Merge contiguous regions of the same type and attribute */
583 static void __init
efi_merge_regions(void)
585 efi_memory_desc_t
*md
, *prev_md
= NULL
;
587 for_each_efi_memory_desc(md
) {
595 if (prev_md
->type
!= md
->type
||
596 prev_md
->attribute
!= md
->attribute
) {
601 prev_size
= prev_md
->num_pages
<< EFI_PAGE_SHIFT
;
603 if (md
->phys_addr
== (prev_md
->phys_addr
+ prev_size
)) {
604 prev_md
->num_pages
+= md
->num_pages
;
605 md
->type
= EFI_RESERVED_TYPE
;
613 static void __init
get_systab_virt_addr(efi_memory_desc_t
*md
)
618 size
= md
->num_pages
<< EFI_PAGE_SHIFT
;
619 end
= md
->phys_addr
+ size
;
620 systab
= (u64
)(unsigned long)efi_phys
.systab
;
621 if (md
->phys_addr
<= systab
&& systab
< end
) {
622 systab
+= md
->virt_addr
- md
->phys_addr
;
623 efi
.systab
= (efi_system_table_t
*)(unsigned long)systab
;
627 static void __init
save_runtime_map(void)
629 #ifdef CONFIG_KEXEC_CORE
630 unsigned long desc_size
;
631 efi_memory_desc_t
*md
;
632 void *tmp
, *q
= NULL
;
635 if (efi_enabled(EFI_OLD_MEMMAP
))
638 desc_size
= efi
.memmap
.desc_size
;
640 for_each_efi_memory_desc(md
) {
641 if (!(md
->attribute
& EFI_MEMORY_RUNTIME
) ||
642 (md
->type
== EFI_BOOT_SERVICES_CODE
) ||
643 (md
->type
== EFI_BOOT_SERVICES_DATA
))
645 tmp
= krealloc(q
, (count
+ 1) * desc_size
, GFP_KERNEL
);
650 memcpy(q
+ count
* desc_size
, md
, desc_size
);
654 efi_runtime_map_setup(q
, count
, desc_size
);
659 pr_err("Error saving runtime map, efi runtime on kexec non-functional!!\n");
663 static void *realloc_pages(void *old_memmap
, int old_shift
)
667 ret
= (void *)__get_free_pages(GFP_KERNEL
, old_shift
+ 1);
672 * A first-time allocation doesn't have anything to copy.
677 memcpy(ret
, old_memmap
, PAGE_SIZE
<< old_shift
);
680 free_pages((unsigned long)old_memmap
, old_shift
);
685 * Iterate the EFI memory map in reverse order because the regions
686 * will be mapped top-down. The end result is the same as if we had
687 * mapped things forward, but doesn't require us to change the
688 * existing implementation of efi_map_region().
690 static inline void *efi_map_next_entry_reverse(void *entry
)
694 return efi
.memmap
.map_end
- efi
.memmap
.desc_size
;
696 entry
-= efi
.memmap
.desc_size
;
697 if (entry
< efi
.memmap
.map
)
704 * efi_map_next_entry - Return the next EFI memory map descriptor
705 * @entry: Previous EFI memory map descriptor
707 * This is a helper function to iterate over the EFI memory map, which
708 * we do in different orders depending on the current configuration.
710 * To begin traversing the memory map @entry must be %NULL.
712 * Returns %NULL when we reach the end of the memory map.
714 static void *efi_map_next_entry(void *entry
)
716 if (!efi_enabled(EFI_OLD_MEMMAP
) && efi_enabled(EFI_64BIT
)) {
718 * Starting in UEFI v2.5 the EFI_PROPERTIES_TABLE
719 * config table feature requires us to map all entries
720 * in the same order as they appear in the EFI memory
721 * map. That is to say, entry N must have a lower
722 * virtual address than entry N+1. This is because the
723 * firmware toolchain leaves relative references in
724 * the code/data sections, which are split and become
725 * separate EFI memory regions. Mapping things
726 * out-of-order leads to the firmware accessing
727 * unmapped addresses.
729 * Since we need to map things this way whether or not
730 * the kernel actually makes use of
731 * EFI_PROPERTIES_TABLE, let's just switch to this
732 * scheme by default for 64-bit.
734 return efi_map_next_entry_reverse(entry
);
739 return efi
.memmap
.map
;
741 entry
+= efi
.memmap
.desc_size
;
742 if (entry
>= efi
.memmap
.map_end
)
748 static bool should_map_region(efi_memory_desc_t
*md
)
751 * Runtime regions always require runtime mappings (obviously).
753 if (md
->attribute
& EFI_MEMORY_RUNTIME
)
757 * 32-bit EFI doesn't suffer from the bug that requires us to
758 * reserve boot services regions, and mixed mode support
759 * doesn't exist for 32-bit kernels.
761 if (IS_ENABLED(CONFIG_X86_32
))
765 * Map all of RAM so that we can access arguments in the 1:1
766 * mapping when making EFI runtime calls.
768 if (IS_ENABLED(CONFIG_EFI_MIXED
) && !efi_is_native()) {
769 if (md
->type
== EFI_CONVENTIONAL_MEMORY
||
770 md
->type
== EFI_LOADER_DATA
||
771 md
->type
== EFI_LOADER_CODE
)
776 * Map boot services regions as a workaround for buggy
777 * firmware that accesses them even when they shouldn't.
779 * See efi_{reserve,free}_boot_services().
781 if (md
->type
== EFI_BOOT_SERVICES_CODE
||
782 md
->type
== EFI_BOOT_SERVICES_DATA
)
789 * Map the efi memory ranges of the runtime services and update new_mmap with
792 static void * __init
efi_map_regions(int *count
, int *pg_shift
)
794 void *p
, *new_memmap
= NULL
;
795 unsigned long left
= 0;
796 unsigned long desc_size
;
797 efi_memory_desc_t
*md
;
799 desc_size
= efi
.memmap
.desc_size
;
802 while ((p
= efi_map_next_entry(p
))) {
805 if (!should_map_region(md
))
809 get_systab_virt_addr(md
);
811 if (left
< desc_size
) {
812 new_memmap
= realloc_pages(new_memmap
, *pg_shift
);
816 left
+= PAGE_SIZE
<< *pg_shift
;
820 memcpy(new_memmap
+ (*count
* desc_size
), md
, desc_size
);
829 static void __init
kexec_enter_virtual_mode(void)
831 #ifdef CONFIG_KEXEC_CORE
832 efi_memory_desc_t
*md
;
833 unsigned int num_pages
;
838 * We don't do virtual mode, since we don't do runtime services, on
841 if (!efi_is_native()) {
843 clear_bit(EFI_RUNTIME_SERVICES
, &efi
.flags
);
847 if (efi_alloc_page_tables()) {
848 pr_err("Failed to allocate EFI page tables\n");
849 clear_bit(EFI_RUNTIME_SERVICES
, &efi
.flags
);
854 * Map efi regions which were passed via setup_data. The virt_addr is a
855 * fixed addr which was used in first kernel of a kexec boot.
857 for_each_efi_memory_desc(md
) {
858 efi_map_region_fixed(md
); /* FIXME: add error handling */
859 get_systab_virt_addr(md
);
866 num_pages
= ALIGN(efi
.memmap
.nr_map
* efi
.memmap
.desc_size
, PAGE_SIZE
);
867 num_pages
>>= PAGE_SHIFT
;
869 if (efi_setup_page_tables(efi
.memmap
.phys_map
, num_pages
)) {
870 clear_bit(EFI_RUNTIME_SERVICES
, &efi
.flags
);
874 efi_sync_low_kernel_mappings();
877 * Now that EFI is in virtual mode, update the function
878 * pointers in the runtime service table to the new virtual addresses.
880 * Call EFI services through wrapper functions.
882 efi
.runtime_version
= efi_systab
.hdr
.revision
;
884 efi_native_runtime_setup();
886 efi
.set_virtual_address_map
= NULL
;
888 if (efi_enabled(EFI_OLD_MEMMAP
) && (__supported_pte_mask
& _PAGE_NX
))
889 runtime_code_page_mkexec();
891 /* clean DUMMY object */
892 efi_delete_dummy_variable();
897 * This function will switch the EFI runtime services to virtual mode.
898 * Essentially, we look through the EFI memmap and map every region that
899 * has the runtime attribute bit set in its memory descriptor into the
900 * efi_pgd page table.
902 * The old method which used to update that memory descriptor with the
903 * virtual address obtained from ioremap() is still supported when the
904 * kernel is booted with efi=old_map on its command line. Same old
905 * method enabled the runtime services to be called without having to
906 * thunk back into physical mode for every invocation.
908 * The new method does a pagetable switch in a preemption-safe manner
909 * so that we're in a different address space when calling a runtime
910 * function. For function arguments passing we do copy the PUDs of the
911 * kernel page table into efi_pgd prior to each call.
913 * Specially for kexec boot, efi runtime maps in previous kernel should
914 * be passed in via setup_data. In that case runtime ranges will be mapped
915 * to the same virtual addresses as the first kernel, see
916 * kexec_enter_virtual_mode().
918 static void __init
__efi_enter_virtual_mode(void)
920 int count
= 0, pg_shift
= 0;
921 void *new_memmap
= NULL
;
926 if (efi_alloc_page_tables()) {
927 pr_err("Failed to allocate EFI page tables\n");
928 clear_bit(EFI_RUNTIME_SERVICES
, &efi
.flags
);
933 new_memmap
= efi_map_regions(&count
, &pg_shift
);
935 pr_err("Error reallocating memory, EFI runtime non-functional!\n");
936 clear_bit(EFI_RUNTIME_SERVICES
, &efi
.flags
);
944 if (efi_setup_page_tables(__pa(new_memmap
), 1 << pg_shift
)) {
945 clear_bit(EFI_RUNTIME_SERVICES
, &efi
.flags
);
949 efi_sync_low_kernel_mappings();
951 if (efi_is_native()) {
952 status
= phys_efi_set_virtual_address_map(
953 efi
.memmap
.desc_size
* count
,
954 efi
.memmap
.desc_size
,
955 efi
.memmap
.desc_version
,
956 (efi_memory_desc_t
*)__pa(new_memmap
));
958 status
= efi_thunk_set_virtual_address_map(
959 efi_phys
.set_virtual_address_map
,
960 efi
.memmap
.desc_size
* count
,
961 efi
.memmap
.desc_size
,
962 efi
.memmap
.desc_version
,
963 (efi_memory_desc_t
*)__pa(new_memmap
));
966 if (status
!= EFI_SUCCESS
) {
967 pr_alert("Unable to switch EFI into virtual mode (status=%lx)!\n",
969 panic("EFI call to SetVirtualAddressMap() failed!");
973 * Now that EFI is in virtual mode, update the function
974 * pointers in the runtime service table to the new virtual addresses.
976 * Call EFI services through wrapper functions.
978 efi
.runtime_version
= efi_systab
.hdr
.revision
;
981 efi_native_runtime_setup();
983 efi_thunk_runtime_setup();
985 efi
.set_virtual_address_map
= NULL
;
988 * Apply more restrictive page table mapping attributes now that
989 * SVAM() has been called and the firmware has performed all
990 * necessary relocation fixups for the new virtual addresses.
992 efi_runtime_update_mappings();
993 efi_dump_pagetable();
996 * We mapped the descriptor array into the EFI pagetable above
997 * but we're not unmapping it here because if we're running in
998 * EFI mixed mode we need all of memory to be accessible when
999 * we pass parameters to the EFI runtime services in the
1002 free_pages((unsigned long)new_memmap
, pg_shift
);
1004 /* clean DUMMY object */
1005 efi_delete_dummy_variable();
1008 void __init
efi_enter_virtual_mode(void)
1010 if (efi_enabled(EFI_PARAVIRT
))
1014 kexec_enter_virtual_mode();
1016 __efi_enter_virtual_mode();
1020 * Convenience functions to obtain memory types and attributes
1022 u32
efi_mem_type(unsigned long phys_addr
)
1024 efi_memory_desc_t
*md
;
1026 if (!efi_enabled(EFI_MEMMAP
))
1029 for_each_efi_memory_desc(md
) {
1030 if ((md
->phys_addr
<= phys_addr
) &&
1031 (phys_addr
< (md
->phys_addr
+
1032 (md
->num_pages
<< EFI_PAGE_SHIFT
))))
1038 static int __init
arch_parse_efi_cmdline(char *str
)
1041 pr_warn("need at least one option\n");
1045 if (parse_option_str(str
, "old_map"))
1046 set_bit(EFI_OLD_MEMMAP
, &efi
.flags
);
1050 early_param("efi", arch_parse_efi_cmdline
);