Merge tag 'm68k-for-v4.9-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert...
[platform/kernel/linux-exynos.git] / arch / x86 / platform / efi / efi.c
1 /*
2  * Common EFI (Extensible Firmware Interface) support functions
3  * Based on Extensible Firmware Interface Specification version 1.0
4  *
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
17  *
18  * Copied from efi_32.c to eliminate the duplicated code between EFI
19  * 32/64 support code. --ying 2007-10-26
20  *
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
24  *
25  * Implemented EFI runtime services and virtual mode calls.  --davidm
26  *
27  * Goutham Rao: <goutham.rao@intel.com>
28  *      Skip non-WB memory and ignore empty memory ranges.
29  */
30
31 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
32
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>
44 #include <linux/io.h>
45 #include <linux/reboot.h>
46 #include <linux/bcd.h>
47
48 #include <asm/setup.h>
49 #include <asm/efi.h>
50 #include <asm/time.h>
51 #include <asm/cacheflush.h>
52 #include <asm/tlbflush.h>
53 #include <asm/x86_init.h>
54 #include <asm/uv/uv.h>
55
56 static struct efi efi_phys __initdata;
57 static efi_system_table_t efi_systab __initdata;
58
59 static efi_config_table_type_t arch_tables[] __initdata = {
60 #ifdef CONFIG_X86_UV
61         {UV_SYSTEM_TABLE_GUID, "UVsystab", &efi.uv_systab},
62 #endif
63         {NULL_GUID, NULL, NULL},
64 };
65
66 u64 efi_setup;          /* efi setup_data physical address */
67
68 static int add_efi_memmap __initdata;
69 static int __init setup_add_efi_memmap(char *arg)
70 {
71         add_efi_memmap = 1;
72         return 0;
73 }
74 early_param("add_efi_memmap", setup_add_efi_memmap);
75
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)
81 {
82         efi_status_t status;
83         unsigned long flags;
84         pgd_t *save_pgd;
85
86         save_pgd = efi_call_phys_prolog();
87
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);
94
95         efi_call_phys_epilog(save_pgd);
96
97         return status;
98 }
99
100 void __init efi_find_mirror(void)
101 {
102         efi_memory_desc_t *md;
103         u64 mirror_size = 0, total_size = 0;
104
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;
108
109                 total_size += size;
110                 if (md->attribute & EFI_MEMORY_MORE_RELIABLE) {
111                         memblock_mark_mirror(start, size);
112                         mirror_size += size;
113                 }
114         }
115         if (mirror_size)
116                 pr_info("Memory: %lldM/%lldM mirrored memory\n",
117                         mirror_size>>20, total_size>>20);
118 }
119
120 /*
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.
124  */
125
126 static void __init do_add_efi_memmap(void)
127 {
128         efi_memory_desc_t *md;
129
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;
133                 int e820_type;
134
135                 switch (md->type) {
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;
143                         else
144                                 e820_type = E820_RESERVED;
145                         break;
146                 case EFI_ACPI_RECLAIM_MEMORY:
147                         e820_type = E820_ACPI;
148                         break;
149                 case EFI_ACPI_MEMORY_NVS:
150                         e820_type = E820_NVS;
151                         break;
152                 case EFI_UNUSABLE_MEMORY:
153                         e820_type = E820_UNUSABLE;
154                         break;
155                 case EFI_PERSISTENT_MEMORY:
156                         e820_type = E820_PMEM;
157                         break;
158                 default:
159                         /*
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
163                          */
164                         e820_type = E820_RESERVED;
165                         break;
166                 }
167                 e820_add_region(start, size, e820_type);
168         }
169         sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
170 }
171
172 int __init efi_memblock_x86_reserve_range(void)
173 {
174         struct efi_info *e = &boot_params.efi_info;
175         struct efi_memory_map_data data;
176         phys_addr_t pmap;
177         int rv;
178
179         if (efi_enabled(EFI_PARAVIRT))
180                 return 0;
181
182 #ifdef CONFIG_X86_32
183         /* Can't handle data above 4GB at this time */
184         if (e->efi_memmap_hi) {
185                 pr_err("Memory map is above 4GB, disabling EFI.\n");
186                 return -EINVAL;
187         }
188         pmap =  e->efi_memmap;
189 #else
190         pmap = (e->efi_memmap | ((__u64)e->efi_memmap_hi << 32));
191 #endif
192         data.phys_map           = pmap;
193         data.size               = e->efi_memmap_size;
194         data.desc_size          = e->efi_memdesc_size;
195         data.desc_version       = e->efi_memdesc_version;
196
197         rv = efi_memmap_init_early(&data);
198         if (rv)
199                 return rv;
200
201         if (add_efi_memmap)
202                 do_add_efi_memmap();
203
204         WARN(efi.memmap.desc_version != 1,
205              "Unexpected EFI_MEMORY_DESCRIPTOR version %ld",
206              efi.memmap.desc_version);
207
208         memblock_reserve(pmap, efi.memmap.nr_map * efi.memmap.desc_size);
209
210         return 0;
211 }
212
213 void __init efi_print_memmap(void)
214 {
215         efi_memory_desc_t *md;
216         int i = 0;
217
218         for_each_efi_memory_desc(md) {
219                 char buf[64];
220
221                 pr_info("mem%02u: %s range=[0x%016llx-0x%016llx] (%lluMB)\n",
222                         i++, efi_md_typeattr_format(buf, sizeof(buf), md),
223                         md->phys_addr,
224                         md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1,
225                         (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
226         }
227 }
228
229 static int __init efi_systab_init(void *phys)
230 {
231         if (efi_enabled(EFI_64BIT)) {
232                 efi_system_table_64_t *systab64;
233                 struct efi_setup_data *data = NULL;
234                 u64 tmp = 0;
235
236                 if (efi_setup) {
237                         data = early_memremap(efi_setup, sizeof(*data));
238                         if (!data)
239                                 return -ENOMEM;
240                 }
241                 systab64 = early_memremap((unsigned long)phys,
242                                          sizeof(*systab64));
243                 if (systab64 == NULL) {
244                         pr_err("Couldn't map the system table!\n");
245                         if (data)
246                                 early_memunmap(data, sizeof(*data));
247                         return -ENOMEM;
248                 }
249
250                 efi_systab.hdr = systab64->hdr;
251                 efi_systab.fw_vendor = data ? (unsigned long)data->fw_vendor :
252                                               systab64->fw_vendor;
253                 tmp |= data ? data->fw_vendor : systab64->fw_vendor;
254                 efi_systab.fw_revision = systab64->fw_revision;
255                 efi_systab.con_in_handle = systab64->con_in_handle;
256                 tmp |= systab64->con_in_handle;
257                 efi_systab.con_in = systab64->con_in;
258                 tmp |= systab64->con_in;
259                 efi_systab.con_out_handle = systab64->con_out_handle;
260                 tmp |= systab64->con_out_handle;
261                 efi_systab.con_out = systab64->con_out;
262                 tmp |= systab64->con_out;
263                 efi_systab.stderr_handle = systab64->stderr_handle;
264                 tmp |= systab64->stderr_handle;
265                 efi_systab.stderr = systab64->stderr;
266                 tmp |= systab64->stderr;
267                 efi_systab.runtime = data ?
268                                      (void *)(unsigned long)data->runtime :
269                                      (void *)(unsigned long)systab64->runtime;
270                 tmp |= data ? data->runtime : systab64->runtime;
271                 efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
272                 tmp |= systab64->boottime;
273                 efi_systab.nr_tables = systab64->nr_tables;
274                 efi_systab.tables = data ? (unsigned long)data->tables :
275                                            systab64->tables;
276                 tmp |= data ? data->tables : systab64->tables;
277
278                 early_memunmap(systab64, sizeof(*systab64));
279                 if (data)
280                         early_memunmap(data, sizeof(*data));
281 #ifdef CONFIG_X86_32
282                 if (tmp >> 32) {
283                         pr_err("EFI data located above 4GB, disabling EFI.\n");
284                         return -EINVAL;
285                 }
286 #endif
287         } else {
288                 efi_system_table_32_t *systab32;
289
290                 systab32 = early_memremap((unsigned long)phys,
291                                          sizeof(*systab32));
292                 if (systab32 == NULL) {
293                         pr_err("Couldn't map the system table!\n");
294                         return -ENOMEM;
295                 }
296
297                 efi_systab.hdr = systab32->hdr;
298                 efi_systab.fw_vendor = systab32->fw_vendor;
299                 efi_systab.fw_revision = systab32->fw_revision;
300                 efi_systab.con_in_handle = systab32->con_in_handle;
301                 efi_systab.con_in = systab32->con_in;
302                 efi_systab.con_out_handle = systab32->con_out_handle;
303                 efi_systab.con_out = systab32->con_out;
304                 efi_systab.stderr_handle = systab32->stderr_handle;
305                 efi_systab.stderr = systab32->stderr;
306                 efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
307                 efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
308                 efi_systab.nr_tables = systab32->nr_tables;
309                 efi_systab.tables = systab32->tables;
310
311                 early_memunmap(systab32, sizeof(*systab32));
312         }
313
314         efi.systab = &efi_systab;
315
316         /*
317          * Verify the EFI Table
318          */
319         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
320                 pr_err("System table signature incorrect!\n");
321                 return -EINVAL;
322         }
323         if ((efi.systab->hdr.revision >> 16) == 0)
324                 pr_err("Warning: System table version %d.%02d, expected 1.00 or greater!\n",
325                        efi.systab->hdr.revision >> 16,
326                        efi.systab->hdr.revision & 0xffff);
327
328         return 0;
329 }
330
331 static int __init efi_runtime_init32(void)
332 {
333         efi_runtime_services_32_t *runtime;
334
335         runtime = early_memremap((unsigned long)efi.systab->runtime,
336                         sizeof(efi_runtime_services_32_t));
337         if (!runtime) {
338                 pr_err("Could not map the runtime service table!\n");
339                 return -ENOMEM;
340         }
341
342         /*
343          * We will only need *early* access to the SetVirtualAddressMap
344          * EFI runtime service. All other runtime services will be called
345          * via the virtual mapping.
346          */
347         efi_phys.set_virtual_address_map =
348                         (efi_set_virtual_address_map_t *)
349                         (unsigned long)runtime->set_virtual_address_map;
350         early_memunmap(runtime, sizeof(efi_runtime_services_32_t));
351
352         return 0;
353 }
354
355 static int __init efi_runtime_init64(void)
356 {
357         efi_runtime_services_64_t *runtime;
358
359         runtime = early_memremap((unsigned long)efi.systab->runtime,
360                         sizeof(efi_runtime_services_64_t));
361         if (!runtime) {
362                 pr_err("Could not map the runtime service table!\n");
363                 return -ENOMEM;
364         }
365
366         /*
367          * We will only need *early* access to the SetVirtualAddressMap
368          * EFI runtime service. All other runtime services will be called
369          * via the virtual mapping.
370          */
371         efi_phys.set_virtual_address_map =
372                         (efi_set_virtual_address_map_t *)
373                         (unsigned long)runtime->set_virtual_address_map;
374         early_memunmap(runtime, sizeof(efi_runtime_services_64_t));
375
376         return 0;
377 }
378
379 static int __init efi_runtime_init(void)
380 {
381         int rv;
382
383         /*
384          * Check out the runtime services table. We need to map
385          * the runtime services table so that we can grab the physical
386          * address of several of the EFI runtime functions, needed to
387          * set the firmware into virtual mode.
388          *
389          * When EFI_PARAVIRT is in force then we could not map runtime
390          * service memory region because we do not have direct access to it.
391          * However, runtime services are available through proxy functions
392          * (e.g. in case of Xen dom0 EFI implementation they call special
393          * hypercall which executes relevant EFI functions) and that is why
394          * they are always enabled.
395          */
396
397         if (!efi_enabled(EFI_PARAVIRT)) {
398                 if (efi_enabled(EFI_64BIT))
399                         rv = efi_runtime_init64();
400                 else
401                         rv = efi_runtime_init32();
402
403                 if (rv)
404                         return rv;
405         }
406
407         set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
408
409         return 0;
410 }
411
412 void __init efi_init(void)
413 {
414         efi_char16_t *c16;
415         char vendor[100] = "unknown";
416         int i = 0;
417         void *tmp;
418
419 #ifdef CONFIG_X86_32
420         if (boot_params.efi_info.efi_systab_hi ||
421             boot_params.efi_info.efi_memmap_hi) {
422                 pr_info("Table located above 4GB, disabling EFI.\n");
423                 return;
424         }
425         efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
426 #else
427         efi_phys.systab = (efi_system_table_t *)
428                           (boot_params.efi_info.efi_systab |
429                           ((__u64)boot_params.efi_info.efi_systab_hi<<32));
430 #endif
431
432         if (efi_systab_init(efi_phys.systab))
433                 return;
434
435         efi.config_table = (unsigned long)efi.systab->tables;
436         efi.fw_vendor    = (unsigned long)efi.systab->fw_vendor;
437         efi.runtime      = (unsigned long)efi.systab->runtime;
438
439         /*
440          * Show what we know for posterity
441          */
442         c16 = tmp = early_memremap(efi.systab->fw_vendor, 2);
443         if (c16) {
444                 for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
445                         vendor[i] = *c16++;
446                 vendor[i] = '\0';
447         } else
448                 pr_err("Could not map the firmware vendor!\n");
449         early_memunmap(tmp, 2);
450
451         pr_info("EFI v%u.%.02u by %s\n",
452                 efi.systab->hdr.revision >> 16,
453                 efi.systab->hdr.revision & 0xffff, vendor);
454
455         if (efi_reuse_config(efi.systab->tables, efi.systab->nr_tables))
456                 return;
457
458         if (efi_config_init(arch_tables))
459                 return;
460
461         /*
462          * Note: We currently don't support runtime services on an EFI
463          * that doesn't match the kernel 32/64-bit mode.
464          */
465
466         if (!efi_runtime_supported())
467                 pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
468         else {
469                 if (efi_runtime_disabled() || efi_runtime_init()) {
470                         efi_memmap_unmap();
471                         return;
472                 }
473         }
474
475         if (efi_enabled(EFI_DBG))
476                 efi_print_memmap();
477 }
478
479 void __init efi_late_init(void)
480 {
481         efi_bgrt_init();
482 }
483
484 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
485 {
486         u64 addr, npages;
487
488         addr = md->virt_addr;
489         npages = md->num_pages;
490
491         memrange_efi_to_native(&addr, &npages);
492
493         if (executable)
494                 set_memory_x(addr, npages);
495         else
496                 set_memory_nx(addr, npages);
497 }
498
499 void __init runtime_code_page_mkexec(void)
500 {
501         efi_memory_desc_t *md;
502
503         /* Make EFI runtime service code area executable */
504         for_each_efi_memory_desc(md) {
505                 if (md->type != EFI_RUNTIME_SERVICES_CODE)
506                         continue;
507
508                 efi_set_executable(md, true);
509         }
510 }
511
512 void __init efi_memory_uc(u64 addr, unsigned long size)
513 {
514         unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
515         u64 npages;
516
517         npages = round_up(size, page_shift) / page_shift;
518         memrange_efi_to_native(&addr, &npages);
519         set_memory_uc(addr, npages);
520 }
521
522 void __init old_map_region(efi_memory_desc_t *md)
523 {
524         u64 start_pfn, end_pfn, end;
525         unsigned long size;
526         void *va;
527
528         start_pfn = PFN_DOWN(md->phys_addr);
529         size      = md->num_pages << PAGE_SHIFT;
530         end       = md->phys_addr + size;
531         end_pfn   = PFN_UP(end);
532
533         if (pfn_range_is_mapped(start_pfn, end_pfn)) {
534                 va = __va(md->phys_addr);
535
536                 if (!(md->attribute & EFI_MEMORY_WB))
537                         efi_memory_uc((u64)(unsigned long)va, size);
538         } else
539                 va = efi_ioremap(md->phys_addr, size,
540                                  md->type, md->attribute);
541
542         md->virt_addr = (u64) (unsigned long) va;
543         if (!va)
544                 pr_err("ioremap of 0x%llX failed!\n",
545                        (unsigned long long)md->phys_addr);
546 }
547
548 /* Merge contiguous regions of the same type and attribute */
549 static void __init efi_merge_regions(void)
550 {
551         efi_memory_desc_t *md, *prev_md = NULL;
552
553         for_each_efi_memory_desc(md) {
554                 u64 prev_size;
555
556                 if (!prev_md) {
557                         prev_md = md;
558                         continue;
559                 }
560
561                 if (prev_md->type != md->type ||
562                     prev_md->attribute != md->attribute) {
563                         prev_md = md;
564                         continue;
565                 }
566
567                 prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
568
569                 if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
570                         prev_md->num_pages += md->num_pages;
571                         md->type = EFI_RESERVED_TYPE;
572                         md->attribute = 0;
573                         continue;
574                 }
575                 prev_md = md;
576         }
577 }
578
579 static void __init get_systab_virt_addr(efi_memory_desc_t *md)
580 {
581         unsigned long size;
582         u64 end, systab;
583
584         size = md->num_pages << EFI_PAGE_SHIFT;
585         end = md->phys_addr + size;
586         systab = (u64)(unsigned long)efi_phys.systab;
587         if (md->phys_addr <= systab && systab < end) {
588                 systab += md->virt_addr - md->phys_addr;
589                 efi.systab = (efi_system_table_t *)(unsigned long)systab;
590         }
591 }
592
593 static void *realloc_pages(void *old_memmap, int old_shift)
594 {
595         void *ret;
596
597         ret = (void *)__get_free_pages(GFP_KERNEL, old_shift + 1);
598         if (!ret)
599                 goto out;
600
601         /*
602          * A first-time allocation doesn't have anything to copy.
603          */
604         if (!old_memmap)
605                 return ret;
606
607         memcpy(ret, old_memmap, PAGE_SIZE << old_shift);
608
609 out:
610         free_pages((unsigned long)old_memmap, old_shift);
611         return ret;
612 }
613
614 /*
615  * Iterate the EFI memory map in reverse order because the regions
616  * will be mapped top-down. The end result is the same as if we had
617  * mapped things forward, but doesn't require us to change the
618  * existing implementation of efi_map_region().
619  */
620 static inline void *efi_map_next_entry_reverse(void *entry)
621 {
622         /* Initial call */
623         if (!entry)
624                 return efi.memmap.map_end - efi.memmap.desc_size;
625
626         entry -= efi.memmap.desc_size;
627         if (entry < efi.memmap.map)
628                 return NULL;
629
630         return entry;
631 }
632
633 /*
634  * efi_map_next_entry - Return the next EFI memory map descriptor
635  * @entry: Previous EFI memory map descriptor
636  *
637  * This is a helper function to iterate over the EFI memory map, which
638  * we do in different orders depending on the current configuration.
639  *
640  * To begin traversing the memory map @entry must be %NULL.
641  *
642  * Returns %NULL when we reach the end of the memory map.
643  */
644 static void *efi_map_next_entry(void *entry)
645 {
646         if (!efi_enabled(EFI_OLD_MEMMAP) && efi_enabled(EFI_64BIT)) {
647                 /*
648                  * Starting in UEFI v2.5 the EFI_PROPERTIES_TABLE
649                  * config table feature requires us to map all entries
650                  * in the same order as they appear in the EFI memory
651                  * map. That is to say, entry N must have a lower
652                  * virtual address than entry N+1. This is because the
653                  * firmware toolchain leaves relative references in
654                  * the code/data sections, which are split and become
655                  * separate EFI memory regions. Mapping things
656                  * out-of-order leads to the firmware accessing
657                  * unmapped addresses.
658                  *
659                  * Since we need to map things this way whether or not
660                  * the kernel actually makes use of
661                  * EFI_PROPERTIES_TABLE, let's just switch to this
662                  * scheme by default for 64-bit.
663                  */
664                 return efi_map_next_entry_reverse(entry);
665         }
666
667         /* Initial call */
668         if (!entry)
669                 return efi.memmap.map;
670
671         entry += efi.memmap.desc_size;
672         if (entry >= efi.memmap.map_end)
673                 return NULL;
674
675         return entry;
676 }
677
678 static bool should_map_region(efi_memory_desc_t *md)
679 {
680         /*
681          * Runtime regions always require runtime mappings (obviously).
682          */
683         if (md->attribute & EFI_MEMORY_RUNTIME)
684                 return true;
685
686         /*
687          * 32-bit EFI doesn't suffer from the bug that requires us to
688          * reserve boot services regions, and mixed mode support
689          * doesn't exist for 32-bit kernels.
690          */
691         if (IS_ENABLED(CONFIG_X86_32))
692                 return false;
693
694         /*
695          * Map all of RAM so that we can access arguments in the 1:1
696          * mapping when making EFI runtime calls.
697          */
698         if (IS_ENABLED(CONFIG_EFI_MIXED) && !efi_is_native()) {
699                 if (md->type == EFI_CONVENTIONAL_MEMORY ||
700                     md->type == EFI_LOADER_DATA ||
701                     md->type == EFI_LOADER_CODE)
702                         return true;
703         }
704
705         /*
706          * Map boot services regions as a workaround for buggy
707          * firmware that accesses them even when they shouldn't.
708          *
709          * See efi_{reserve,free}_boot_services().
710          */
711         if (md->type == EFI_BOOT_SERVICES_CODE ||
712             md->type == EFI_BOOT_SERVICES_DATA)
713                 return true;
714
715         return false;
716 }
717
718 /*
719  * Map the efi memory ranges of the runtime services and update new_mmap with
720  * virtual addresses.
721  */
722 static void * __init efi_map_regions(int *count, int *pg_shift)
723 {
724         void *p, *new_memmap = NULL;
725         unsigned long left = 0;
726         unsigned long desc_size;
727         efi_memory_desc_t *md;
728
729         desc_size = efi.memmap.desc_size;
730
731         p = NULL;
732         while ((p = efi_map_next_entry(p))) {
733                 md = p;
734
735                 if (!should_map_region(md))
736                         continue;
737
738                 efi_map_region(md);
739                 get_systab_virt_addr(md);
740
741                 if (left < desc_size) {
742                         new_memmap = realloc_pages(new_memmap, *pg_shift);
743                         if (!new_memmap)
744                                 return NULL;
745
746                         left += PAGE_SIZE << *pg_shift;
747                         (*pg_shift)++;
748                 }
749
750                 memcpy(new_memmap + (*count * desc_size), md, desc_size);
751
752                 left -= desc_size;
753                 (*count)++;
754         }
755
756         return new_memmap;
757 }
758
759 static void __init kexec_enter_virtual_mode(void)
760 {
761 #ifdef CONFIG_KEXEC_CORE
762         efi_memory_desc_t *md;
763         unsigned int num_pages;
764
765         efi.systab = NULL;
766
767         /*
768          * We don't do virtual mode, since we don't do runtime services, on
769          * non-native EFI
770          */
771         if (!efi_is_native()) {
772                 efi_memmap_unmap();
773                 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
774                 return;
775         }
776
777         if (efi_alloc_page_tables()) {
778                 pr_err("Failed to allocate EFI page tables\n");
779                 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
780                 return;
781         }
782
783         /*
784         * Map efi regions which were passed via setup_data. The virt_addr is a
785         * fixed addr which was used in first kernel of a kexec boot.
786         */
787         for_each_efi_memory_desc(md) {
788                 efi_map_region_fixed(md); /* FIXME: add error handling */
789                 get_systab_virt_addr(md);
790         }
791
792         /*
793          * Unregister the early EFI memmap from efi_init() and install
794          * the new EFI memory map.
795          */
796         efi_memmap_unmap();
797
798         if (efi_memmap_init_late(efi.memmap.phys_map,
799                                  efi.memmap.desc_size * efi.memmap.nr_map)) {
800                 pr_err("Failed to remap late EFI memory map\n");
801                 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
802                 return;
803         }
804
805         BUG_ON(!efi.systab);
806
807         num_pages = ALIGN(efi.memmap.nr_map * efi.memmap.desc_size, PAGE_SIZE);
808         num_pages >>= PAGE_SHIFT;
809
810         if (efi_setup_page_tables(efi.memmap.phys_map, num_pages)) {
811                 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
812                 return;
813         }
814
815         efi_sync_low_kernel_mappings();
816
817         /*
818          * Now that EFI is in virtual mode, update the function
819          * pointers in the runtime service table to the new virtual addresses.
820          *
821          * Call EFI services through wrapper functions.
822          */
823         efi.runtime_version = efi_systab.hdr.revision;
824
825         efi_native_runtime_setup();
826
827         efi.set_virtual_address_map = NULL;
828
829         if (efi_enabled(EFI_OLD_MEMMAP) && (__supported_pte_mask & _PAGE_NX))
830                 runtime_code_page_mkexec();
831
832         /* clean DUMMY object */
833         efi_delete_dummy_variable();
834 #endif
835 }
836
837 /*
838  * This function will switch the EFI runtime services to virtual mode.
839  * Essentially, we look through the EFI memmap and map every region that
840  * has the runtime attribute bit set in its memory descriptor into the
841  * efi_pgd page table.
842  *
843  * The old method which used to update that memory descriptor with the
844  * virtual address obtained from ioremap() is still supported when the
845  * kernel is booted with efi=old_map on its command line. Same old
846  * method enabled the runtime services to be called without having to
847  * thunk back into physical mode for every invocation.
848  *
849  * The new method does a pagetable switch in a preemption-safe manner
850  * so that we're in a different address space when calling a runtime
851  * function. For function arguments passing we do copy the PUDs of the
852  * kernel page table into efi_pgd prior to each call.
853  *
854  * Specially for kexec boot, efi runtime maps in previous kernel should
855  * be passed in via setup_data. In that case runtime ranges will be mapped
856  * to the same virtual addresses as the first kernel, see
857  * kexec_enter_virtual_mode().
858  */
859 static void __init __efi_enter_virtual_mode(void)
860 {
861         int count = 0, pg_shift = 0;
862         void *new_memmap = NULL;
863         efi_status_t status;
864         phys_addr_t pa;
865
866         efi.systab = NULL;
867
868         if (efi_alloc_page_tables()) {
869                 pr_err("Failed to allocate EFI page tables\n");
870                 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
871                 return;
872         }
873
874         efi_merge_regions();
875         new_memmap = efi_map_regions(&count, &pg_shift);
876         if (!new_memmap) {
877                 pr_err("Error reallocating memory, EFI runtime non-functional!\n");
878                 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
879                 return;
880         }
881
882         pa = __pa(new_memmap);
883
884         /*
885          * Unregister the early EFI memmap from efi_init() and install
886          * the new EFI memory map that we are about to pass to the
887          * firmware via SetVirtualAddressMap().
888          */
889         efi_memmap_unmap();
890
891         if (efi_memmap_init_late(pa, efi.memmap.desc_size * count)) {
892                 pr_err("Failed to remap late EFI memory map\n");
893                 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
894                 return;
895         }
896
897         BUG_ON(!efi.systab);
898
899         if (efi_setup_page_tables(pa, 1 << pg_shift)) {
900                 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
901                 return;
902         }
903
904         efi_sync_low_kernel_mappings();
905
906         if (efi_is_native()) {
907                 status = phys_efi_set_virtual_address_map(
908                                 efi.memmap.desc_size * count,
909                                 efi.memmap.desc_size,
910                                 efi.memmap.desc_version,
911                                 (efi_memory_desc_t *)pa);
912         } else {
913                 status = efi_thunk_set_virtual_address_map(
914                                 efi_phys.set_virtual_address_map,
915                                 efi.memmap.desc_size * count,
916                                 efi.memmap.desc_size,
917                                 efi.memmap.desc_version,
918                                 (efi_memory_desc_t *)pa);
919         }
920
921         if (status != EFI_SUCCESS) {
922                 pr_alert("Unable to switch EFI into virtual mode (status=%lx)!\n",
923                          status);
924                 panic("EFI call to SetVirtualAddressMap() failed!");
925         }
926
927         /*
928          * Now that EFI is in virtual mode, update the function
929          * pointers in the runtime service table to the new virtual addresses.
930          *
931          * Call EFI services through wrapper functions.
932          */
933         efi.runtime_version = efi_systab.hdr.revision;
934
935         if (efi_is_native())
936                 efi_native_runtime_setup();
937         else
938                 efi_thunk_runtime_setup();
939
940         efi.set_virtual_address_map = NULL;
941
942         /*
943          * Apply more restrictive page table mapping attributes now that
944          * SVAM() has been called and the firmware has performed all
945          * necessary relocation fixups for the new virtual addresses.
946          */
947         efi_runtime_update_mappings();
948         efi_dump_pagetable();
949
950         /* clean DUMMY object */
951         efi_delete_dummy_variable();
952 }
953
954 void __init efi_enter_virtual_mode(void)
955 {
956         if (efi_enabled(EFI_PARAVIRT))
957                 return;
958
959         if (efi_setup)
960                 kexec_enter_virtual_mode();
961         else
962                 __efi_enter_virtual_mode();
963 }
964
965 /*
966  * Convenience functions to obtain memory types and attributes
967  */
968 u32 efi_mem_type(unsigned long phys_addr)
969 {
970         efi_memory_desc_t *md;
971
972         if (!efi_enabled(EFI_MEMMAP))
973                 return 0;
974
975         for_each_efi_memory_desc(md) {
976                 if ((md->phys_addr <= phys_addr) &&
977                     (phys_addr < (md->phys_addr +
978                                   (md->num_pages << EFI_PAGE_SHIFT))))
979                         return md->type;
980         }
981         return 0;
982 }
983
984 static int __init arch_parse_efi_cmdline(char *str)
985 {
986         if (!str) {
987                 pr_warn("need at least one option\n");
988                 return -EINVAL;
989         }
990
991         if (parse_option_str(str, "old_map"))
992                 set_bit(EFI_OLD_MEMMAP, &efi.flags);
993
994         return 0;
995 }
996 early_param("efi", arch_parse_efi_cmdline);