]> asedeno.scripts.mit.edu Git - linux.git/blob - drivers/firmware/efi/efi.c
Merge branch 'drm-fixes-4.20' of git://people.freedesktop.org/~agd5f/linux into drm-fixes
[linux.git] / drivers / firmware / efi / efi.c
1 /*
2  * efi.c - EFI subsystem
3  *
4  * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
5  * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
6  * Copyright (C) 2013 Tom Gundersen <teg@jklm.no>
7  *
8  * This code registers /sys/firmware/efi{,/efivars} when EFI is supported,
9  * allowing the efivarfs to be mounted or the efivars module to be loaded.
10  * The existance of /sys/firmware/efi may also be used by userspace to
11  * determine that the system supports EFI.
12  *
13  * This file is released under the GPLv2.
14  */
15
16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17
18 #include <linux/kobject.h>
19 #include <linux/module.h>
20 #include <linux/init.h>
21 #include <linux/device.h>
22 #include <linux/efi.h>
23 #include <linux/of.h>
24 #include <linux/of_fdt.h>
25 #include <linux/io.h>
26 #include <linux/kexec.h>
27 #include <linux/platform_device.h>
28 #include <linux/random.h>
29 #include <linux/reboot.h>
30 #include <linux/slab.h>
31 #include <linux/acpi.h>
32 #include <linux/ucs2_string.h>
33 #include <linux/memblock.h>
34
35 #include <asm/early_ioremap.h>
36
37 struct efi __read_mostly efi = {
38         .mps                    = EFI_INVALID_TABLE_ADDR,
39         .acpi                   = EFI_INVALID_TABLE_ADDR,
40         .acpi20                 = EFI_INVALID_TABLE_ADDR,
41         .smbios                 = EFI_INVALID_TABLE_ADDR,
42         .smbios3                = EFI_INVALID_TABLE_ADDR,
43         .sal_systab             = EFI_INVALID_TABLE_ADDR,
44         .boot_info              = EFI_INVALID_TABLE_ADDR,
45         .hcdp                   = EFI_INVALID_TABLE_ADDR,
46         .uga                    = EFI_INVALID_TABLE_ADDR,
47         .uv_systab              = EFI_INVALID_TABLE_ADDR,
48         .fw_vendor              = EFI_INVALID_TABLE_ADDR,
49         .runtime                = EFI_INVALID_TABLE_ADDR,
50         .config_table           = EFI_INVALID_TABLE_ADDR,
51         .esrt                   = EFI_INVALID_TABLE_ADDR,
52         .properties_table       = EFI_INVALID_TABLE_ADDR,
53         .mem_attr_table         = EFI_INVALID_TABLE_ADDR,
54         .rng_seed               = EFI_INVALID_TABLE_ADDR,
55         .tpm_log                = EFI_INVALID_TABLE_ADDR,
56         .mem_reserve            = EFI_INVALID_TABLE_ADDR,
57 };
58 EXPORT_SYMBOL(efi);
59
60 static unsigned long *efi_tables[] = {
61         &efi.mps,
62         &efi.acpi,
63         &efi.acpi20,
64         &efi.smbios,
65         &efi.smbios3,
66         &efi.sal_systab,
67         &efi.boot_info,
68         &efi.hcdp,
69         &efi.uga,
70         &efi.uv_systab,
71         &efi.fw_vendor,
72         &efi.runtime,
73         &efi.config_table,
74         &efi.esrt,
75         &efi.properties_table,
76         &efi.mem_attr_table,
77 };
78
79 struct mm_struct efi_mm = {
80         .mm_rb                  = RB_ROOT,
81         .mm_users               = ATOMIC_INIT(2),
82         .mm_count               = ATOMIC_INIT(1),
83         .mmap_sem               = __RWSEM_INITIALIZER(efi_mm.mmap_sem),
84         .page_table_lock        = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock),
85         .mmlist                 = LIST_HEAD_INIT(efi_mm.mmlist),
86         .cpu_bitmap             = { [BITS_TO_LONGS(NR_CPUS)] = 0},
87 };
88
89 struct workqueue_struct *efi_rts_wq;
90
91 static bool disable_runtime;
92 static int __init setup_noefi(char *arg)
93 {
94         disable_runtime = true;
95         return 0;
96 }
97 early_param("noefi", setup_noefi);
98
99 bool efi_runtime_disabled(void)
100 {
101         return disable_runtime;
102 }
103
104 static int __init parse_efi_cmdline(char *str)
105 {
106         if (!str) {
107                 pr_warn("need at least one option\n");
108                 return -EINVAL;
109         }
110
111         if (parse_option_str(str, "debug"))
112                 set_bit(EFI_DBG, &efi.flags);
113
114         if (parse_option_str(str, "noruntime"))
115                 disable_runtime = true;
116
117         return 0;
118 }
119 early_param("efi", parse_efi_cmdline);
120
121 struct kobject *efi_kobj;
122
123 /*
124  * Let's not leave out systab information that snuck into
125  * the efivars driver
126  * Note, do not add more fields in systab sysfs file as it breaks sysfs
127  * one value per file rule!
128  */
129 static ssize_t systab_show(struct kobject *kobj,
130                            struct kobj_attribute *attr, char *buf)
131 {
132         char *str = buf;
133
134         if (!kobj || !buf)
135                 return -EINVAL;
136
137         if (efi.mps != EFI_INVALID_TABLE_ADDR)
138                 str += sprintf(str, "MPS=0x%lx\n", efi.mps);
139         if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
140                 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
141         if (efi.acpi != EFI_INVALID_TABLE_ADDR)
142                 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
143         /*
144          * If both SMBIOS and SMBIOS3 entry points are implemented, the
145          * SMBIOS3 entry point shall be preferred, so we list it first to
146          * let applications stop parsing after the first match.
147          */
148         if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
149                 str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
150         if (efi.smbios != EFI_INVALID_TABLE_ADDR)
151                 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
152         if (efi.hcdp != EFI_INVALID_TABLE_ADDR)
153                 str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp);
154         if (efi.boot_info != EFI_INVALID_TABLE_ADDR)
155                 str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info);
156         if (efi.uga != EFI_INVALID_TABLE_ADDR)
157                 str += sprintf(str, "UGA=0x%lx\n", efi.uga);
158
159         return str - buf;
160 }
161
162 static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400);
163
164 #define EFI_FIELD(var) efi.var
165
166 #define EFI_ATTR_SHOW(name) \
167 static ssize_t name##_show(struct kobject *kobj, \
168                                 struct kobj_attribute *attr, char *buf) \
169 { \
170         return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \
171 }
172
173 EFI_ATTR_SHOW(fw_vendor);
174 EFI_ATTR_SHOW(runtime);
175 EFI_ATTR_SHOW(config_table);
176
177 static ssize_t fw_platform_size_show(struct kobject *kobj,
178                                      struct kobj_attribute *attr, char *buf)
179 {
180         return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
181 }
182
183 static struct kobj_attribute efi_attr_fw_vendor = __ATTR_RO(fw_vendor);
184 static struct kobj_attribute efi_attr_runtime = __ATTR_RO(runtime);
185 static struct kobj_attribute efi_attr_config_table = __ATTR_RO(config_table);
186 static struct kobj_attribute efi_attr_fw_platform_size =
187         __ATTR_RO(fw_platform_size);
188
189 static struct attribute *efi_subsys_attrs[] = {
190         &efi_attr_systab.attr,
191         &efi_attr_fw_vendor.attr,
192         &efi_attr_runtime.attr,
193         &efi_attr_config_table.attr,
194         &efi_attr_fw_platform_size.attr,
195         NULL,
196 };
197
198 static umode_t efi_attr_is_visible(struct kobject *kobj,
199                                    struct attribute *attr, int n)
200 {
201         if (attr == &efi_attr_fw_vendor.attr) {
202                 if (efi_enabled(EFI_PARAVIRT) ||
203                                 efi.fw_vendor == EFI_INVALID_TABLE_ADDR)
204                         return 0;
205         } else if (attr == &efi_attr_runtime.attr) {
206                 if (efi.runtime == EFI_INVALID_TABLE_ADDR)
207                         return 0;
208         } else if (attr == &efi_attr_config_table.attr) {
209                 if (efi.config_table == EFI_INVALID_TABLE_ADDR)
210                         return 0;
211         }
212
213         return attr->mode;
214 }
215
216 static const struct attribute_group efi_subsys_attr_group = {
217         .attrs = efi_subsys_attrs,
218         .is_visible = efi_attr_is_visible,
219 };
220
221 static struct efivars generic_efivars;
222 static struct efivar_operations generic_ops;
223
224 static int generic_ops_register(void)
225 {
226         generic_ops.get_variable = efi.get_variable;
227         generic_ops.set_variable = efi.set_variable;
228         generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
229         generic_ops.get_next_variable = efi.get_next_variable;
230         generic_ops.query_variable_store = efi_query_variable_store;
231
232         return efivars_register(&generic_efivars, &generic_ops, efi_kobj);
233 }
234
235 static void generic_ops_unregister(void)
236 {
237         efivars_unregister(&generic_efivars);
238 }
239
240 #if IS_ENABLED(CONFIG_ACPI)
241 #define EFIVAR_SSDT_NAME_MAX    16
242 static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
243 static int __init efivar_ssdt_setup(char *str)
244 {
245         if (strlen(str) < sizeof(efivar_ssdt))
246                 memcpy(efivar_ssdt, str, strlen(str));
247         else
248                 pr_warn("efivar_ssdt: name too long: %s\n", str);
249         return 0;
250 }
251 __setup("efivar_ssdt=", efivar_ssdt_setup);
252
253 static __init int efivar_ssdt_iter(efi_char16_t *name, efi_guid_t vendor,
254                                    unsigned long name_size, void *data)
255 {
256         struct efivar_entry *entry;
257         struct list_head *list = data;
258         char utf8_name[EFIVAR_SSDT_NAME_MAX];
259         int limit = min_t(unsigned long, EFIVAR_SSDT_NAME_MAX, name_size);
260
261         ucs2_as_utf8(utf8_name, name, limit - 1);
262         if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
263                 return 0;
264
265         entry = kmalloc(sizeof(*entry), GFP_KERNEL);
266         if (!entry)
267                 return 0;
268
269         memcpy(entry->var.VariableName, name, name_size);
270         memcpy(&entry->var.VendorGuid, &vendor, sizeof(efi_guid_t));
271
272         efivar_entry_add(entry, list);
273
274         return 0;
275 }
276
277 static __init int efivar_ssdt_load(void)
278 {
279         LIST_HEAD(entries);
280         struct efivar_entry *entry, *aux;
281         unsigned long size;
282         void *data;
283         int ret;
284
285         ret = efivar_init(efivar_ssdt_iter, &entries, true, &entries);
286
287         list_for_each_entry_safe(entry, aux, &entries, list) {
288                 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt,
289                         &entry->var.VendorGuid);
290
291                 list_del(&entry->list);
292
293                 ret = efivar_entry_size(entry, &size);
294                 if (ret) {
295                         pr_err("failed to get var size\n");
296                         goto free_entry;
297                 }
298
299                 data = kmalloc(size, GFP_KERNEL);
300                 if (!data) {
301                         ret = -ENOMEM;
302                         goto free_entry;
303                 }
304
305                 ret = efivar_entry_get(entry, NULL, &size, data);
306                 if (ret) {
307                         pr_err("failed to get var data\n");
308                         goto free_data;
309                 }
310
311                 ret = acpi_load_table(data);
312                 if (ret) {
313                         pr_err("failed to load table: %d\n", ret);
314                         goto free_data;
315                 }
316
317                 goto free_entry;
318
319 free_data:
320                 kfree(data);
321
322 free_entry:
323                 kfree(entry);
324         }
325
326         return ret;
327 }
328 #else
329 static inline int efivar_ssdt_load(void) { return 0; }
330 #endif
331
332 /*
333  * We register the efi subsystem with the firmware subsystem and the
334  * efivars subsystem with the efi subsystem, if the system was booted with
335  * EFI.
336  */
337 static int __init efisubsys_init(void)
338 {
339         int error;
340
341         if (!efi_enabled(EFI_BOOT))
342                 return 0;
343
344         /*
345          * Since we process only one efi_runtime_service() at a time, an
346          * ordered workqueue (which creates only one execution context)
347          * should suffice all our needs.
348          */
349         efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0);
350         if (!efi_rts_wq) {
351                 pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n");
352                 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
353                 return 0;
354         }
355
356         /* We register the efi directory at /sys/firmware/efi */
357         efi_kobj = kobject_create_and_add("efi", firmware_kobj);
358         if (!efi_kobj) {
359                 pr_err("efi: Firmware registration failed.\n");
360                 return -ENOMEM;
361         }
362
363         error = generic_ops_register();
364         if (error)
365                 goto err_put;
366
367         if (efi_enabled(EFI_RUNTIME_SERVICES))
368                 efivar_ssdt_load();
369
370         error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
371         if (error) {
372                 pr_err("efi: Sysfs attribute export failed with error %d.\n",
373                        error);
374                 goto err_unregister;
375         }
376
377         error = efi_runtime_map_init(efi_kobj);
378         if (error)
379                 goto err_remove_group;
380
381         /* and the standard mountpoint for efivarfs */
382         error = sysfs_create_mount_point(efi_kobj, "efivars");
383         if (error) {
384                 pr_err("efivars: Subsystem registration failed.\n");
385                 goto err_remove_group;
386         }
387
388         return 0;
389
390 err_remove_group:
391         sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
392 err_unregister:
393         generic_ops_unregister();
394 err_put:
395         kobject_put(efi_kobj);
396         return error;
397 }
398
399 subsys_initcall(efisubsys_init);
400
401 /*
402  * Find the efi memory descriptor for a given physical address.  Given a
403  * physical address, determine if it exists within an EFI Memory Map entry,
404  * and if so, populate the supplied memory descriptor with the appropriate
405  * data.
406  */
407 int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
408 {
409         efi_memory_desc_t *md;
410
411         if (!efi_enabled(EFI_MEMMAP)) {
412                 pr_err_once("EFI_MEMMAP is not enabled.\n");
413                 return -EINVAL;
414         }
415
416         if (!out_md) {
417                 pr_err_once("out_md is null.\n");
418                 return -EINVAL;
419         }
420
421         for_each_efi_memory_desc(md) {
422                 u64 size;
423                 u64 end;
424
425                 size = md->num_pages << EFI_PAGE_SHIFT;
426                 end = md->phys_addr + size;
427                 if (phys_addr >= md->phys_addr && phys_addr < end) {
428                         memcpy(out_md, md, sizeof(*out_md));
429                         return 0;
430                 }
431         }
432         return -ENOENT;
433 }
434
435 /*
436  * Calculate the highest address of an efi memory descriptor.
437  */
438 u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
439 {
440         u64 size = md->num_pages << EFI_PAGE_SHIFT;
441         u64 end = md->phys_addr + size;
442         return end;
443 }
444
445 void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {}
446
447 /**
448  * efi_mem_reserve - Reserve an EFI memory region
449  * @addr: Physical address to reserve
450  * @size: Size of reservation
451  *
452  * Mark a region as reserved from general kernel allocation and
453  * prevent it being released by efi_free_boot_services().
454  *
455  * This function should be called drivers once they've parsed EFI
456  * configuration tables to figure out where their data lives, e.g.
457  * efi_esrt_init().
458  */
459 void __init efi_mem_reserve(phys_addr_t addr, u64 size)
460 {
461         if (!memblock_is_region_reserved(addr, size))
462                 memblock_reserve(addr, size);
463
464         /*
465          * Some architectures (x86) reserve all boot services ranges
466          * until efi_free_boot_services() because of buggy firmware
467          * implementations. This means the above memblock_reserve() is
468          * superfluous on x86 and instead what it needs to do is
469          * ensure the @start, @size is not freed.
470          */
471         efi_arch_mem_reserve(addr, size);
472 }
473
474 static __initdata efi_config_table_type_t common_tables[] = {
475         {ACPI_20_TABLE_GUID, "ACPI 2.0", &efi.acpi20},
476         {ACPI_TABLE_GUID, "ACPI", &efi.acpi},
477         {HCDP_TABLE_GUID, "HCDP", &efi.hcdp},
478         {MPS_TABLE_GUID, "MPS", &efi.mps},
479         {SAL_SYSTEM_TABLE_GUID, "SALsystab", &efi.sal_systab},
480         {SMBIOS_TABLE_GUID, "SMBIOS", &efi.smbios},
481         {SMBIOS3_TABLE_GUID, "SMBIOS 3.0", &efi.smbios3},
482         {UGA_IO_PROTOCOL_GUID, "UGA", &efi.uga},
483         {EFI_SYSTEM_RESOURCE_TABLE_GUID, "ESRT", &efi.esrt},
484         {EFI_PROPERTIES_TABLE_GUID, "PROP", &efi.properties_table},
485         {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, "MEMATTR", &efi.mem_attr_table},
486         {LINUX_EFI_RANDOM_SEED_TABLE_GUID, "RNG", &efi.rng_seed},
487         {LINUX_EFI_TPM_EVENT_LOG_GUID, "TPMEventLog", &efi.tpm_log},
488         {LINUX_EFI_MEMRESERVE_TABLE_GUID, "MEMRESERVE", &efi.mem_reserve},
489         {NULL_GUID, NULL, NULL},
490 };
491
492 static __init int match_config_table(efi_guid_t *guid,
493                                      unsigned long table,
494                                      efi_config_table_type_t *table_types)
495 {
496         int i;
497
498         if (table_types) {
499                 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
500                         if (!efi_guidcmp(*guid, table_types[i].guid)) {
501                                 *(table_types[i].ptr) = table;
502                                 if (table_types[i].name)
503                                         pr_cont(" %s=0x%lx ",
504                                                 table_types[i].name, table);
505                                 return 1;
506                         }
507                 }
508         }
509
510         return 0;
511 }
512
513 int __init efi_config_parse_tables(void *config_tables, int count, int sz,
514                                    efi_config_table_type_t *arch_tables)
515 {
516         void *tablep;
517         int i;
518
519         tablep = config_tables;
520         pr_info("");
521         for (i = 0; i < count; i++) {
522                 efi_guid_t guid;
523                 unsigned long table;
524
525                 if (efi_enabled(EFI_64BIT)) {
526                         u64 table64;
527                         guid = ((efi_config_table_64_t *)tablep)->guid;
528                         table64 = ((efi_config_table_64_t *)tablep)->table;
529                         table = table64;
530 #ifndef CONFIG_64BIT
531                         if (table64 >> 32) {
532                                 pr_cont("\n");
533                                 pr_err("Table located above 4GB, disabling EFI.\n");
534                                 return -EINVAL;
535                         }
536 #endif
537                 } else {
538                         guid = ((efi_config_table_32_t *)tablep)->guid;
539                         table = ((efi_config_table_32_t *)tablep)->table;
540                 }
541
542                 if (!match_config_table(&guid, table, common_tables))
543                         match_config_table(&guid, table, arch_tables);
544
545                 tablep += sz;
546         }
547         pr_cont("\n");
548         set_bit(EFI_CONFIG_TABLES, &efi.flags);
549
550         if (efi.rng_seed != EFI_INVALID_TABLE_ADDR) {
551                 struct linux_efi_random_seed *seed;
552                 u32 size = 0;
553
554                 seed = early_memremap(efi.rng_seed, sizeof(*seed));
555                 if (seed != NULL) {
556                         size = seed->size;
557                         early_memunmap(seed, sizeof(*seed));
558                 } else {
559                         pr_err("Could not map UEFI random seed!\n");
560                 }
561                 if (size > 0) {
562                         seed = early_memremap(efi.rng_seed,
563                                               sizeof(*seed) + size);
564                         if (seed != NULL) {
565                                 pr_notice("seeding entropy pool\n");
566                                 add_device_randomness(seed->bits, seed->size);
567                                 early_memunmap(seed, sizeof(*seed) + size);
568                         } else {
569                                 pr_err("Could not map UEFI random seed!\n");
570                         }
571                 }
572         }
573
574         if (efi_enabled(EFI_MEMMAP))
575                 efi_memattr_init();
576
577         efi_tpm_eventlog_init();
578
579         /* Parse the EFI Properties table if it exists */
580         if (efi.properties_table != EFI_INVALID_TABLE_ADDR) {
581                 efi_properties_table_t *tbl;
582
583                 tbl = early_memremap(efi.properties_table, sizeof(*tbl));
584                 if (tbl == NULL) {
585                         pr_err("Could not map Properties table!\n");
586                         return -ENOMEM;
587                 }
588
589                 if (tbl->memory_protection_attribute &
590                     EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA)
591                         set_bit(EFI_NX_PE_DATA, &efi.flags);
592
593                 early_memunmap(tbl, sizeof(*tbl));
594         }
595         return 0;
596 }
597
598 int __init efi_apply_persistent_mem_reservations(void)
599 {
600         if (efi.mem_reserve != EFI_INVALID_TABLE_ADDR) {
601                 unsigned long prsv = efi.mem_reserve;
602
603                 while (prsv) {
604                         struct linux_efi_memreserve *rsv;
605
606                         /* reserve the entry itself */
607                         memblock_reserve(prsv, sizeof(*rsv));
608
609                         rsv = early_memremap(prsv, sizeof(*rsv));
610                         if (rsv == NULL) {
611                                 pr_err("Could not map UEFI memreserve entry!\n");
612                                 return -ENOMEM;
613                         }
614
615                         if (rsv->size)
616                                 memblock_reserve(rsv->base, rsv->size);
617
618                         prsv = rsv->next;
619                         early_memunmap(rsv, sizeof(*rsv));
620                 }
621         }
622
623         return 0;
624 }
625
626 int __init efi_config_init(efi_config_table_type_t *arch_tables)
627 {
628         void *config_tables;
629         int sz, ret;
630
631         if (efi_enabled(EFI_64BIT))
632                 sz = sizeof(efi_config_table_64_t);
633         else
634                 sz = sizeof(efi_config_table_32_t);
635
636         /*
637          * Let's see what config tables the firmware passed to us.
638          */
639         config_tables = early_memremap(efi.systab->tables,
640                                        efi.systab->nr_tables * sz);
641         if (config_tables == NULL) {
642                 pr_err("Could not map Configuration table!\n");
643                 return -ENOMEM;
644         }
645
646         ret = efi_config_parse_tables(config_tables, efi.systab->nr_tables, sz,
647                                       arch_tables);
648
649         early_memunmap(config_tables, efi.systab->nr_tables * sz);
650         return ret;
651 }
652
653 #ifdef CONFIG_EFI_VARS_MODULE
654 static int __init efi_load_efivars(void)
655 {
656         struct platform_device *pdev;
657
658         if (!efi_enabled(EFI_RUNTIME_SERVICES))
659                 return 0;
660
661         pdev = platform_device_register_simple("efivars", 0, NULL, 0);
662         return PTR_ERR_OR_ZERO(pdev);
663 }
664 device_initcall(efi_load_efivars);
665 #endif
666
667 #ifdef CONFIG_EFI_PARAMS_FROM_FDT
668
669 #define UEFI_PARAM(name, prop, field)                      \
670         {                                                  \
671                 { name },                                  \
672                 { prop },                                  \
673                 offsetof(struct efi_fdt_params, field),    \
674                 FIELD_SIZEOF(struct efi_fdt_params, field) \
675         }
676
677 struct params {
678         const char name[32];
679         const char propname[32];
680         int offset;
681         int size;
682 };
683
684 static __initdata struct params fdt_params[] = {
685         UEFI_PARAM("System Table", "linux,uefi-system-table", system_table),
686         UEFI_PARAM("MemMap Address", "linux,uefi-mmap-start", mmap),
687         UEFI_PARAM("MemMap Size", "linux,uefi-mmap-size", mmap_size),
688         UEFI_PARAM("MemMap Desc. Size", "linux,uefi-mmap-desc-size", desc_size),
689         UEFI_PARAM("MemMap Desc. Version", "linux,uefi-mmap-desc-ver", desc_ver)
690 };
691
692 static __initdata struct params xen_fdt_params[] = {
693         UEFI_PARAM("System Table", "xen,uefi-system-table", system_table),
694         UEFI_PARAM("MemMap Address", "xen,uefi-mmap-start", mmap),
695         UEFI_PARAM("MemMap Size", "xen,uefi-mmap-size", mmap_size),
696         UEFI_PARAM("MemMap Desc. Size", "xen,uefi-mmap-desc-size", desc_size),
697         UEFI_PARAM("MemMap Desc. Version", "xen,uefi-mmap-desc-ver", desc_ver)
698 };
699
700 #define EFI_FDT_PARAMS_SIZE     ARRAY_SIZE(fdt_params)
701
702 static __initdata struct {
703         const char *uname;
704         const char *subnode;
705         struct params *params;
706 } dt_params[] = {
707         { "hypervisor", "uefi", xen_fdt_params },
708         { "chosen", NULL, fdt_params },
709 };
710
711 struct param_info {
712         int found;
713         void *params;
714         const char *missing;
715 };
716
717 static int __init __find_uefi_params(unsigned long node,
718                                      struct param_info *info,
719                                      struct params *params)
720 {
721         const void *prop;
722         void *dest;
723         u64 val;
724         int i, len;
725
726         for (i = 0; i < EFI_FDT_PARAMS_SIZE; i++) {
727                 prop = of_get_flat_dt_prop(node, params[i].propname, &len);
728                 if (!prop) {
729                         info->missing = params[i].name;
730                         return 0;
731                 }
732
733                 dest = info->params + params[i].offset;
734                 info->found++;
735
736                 val = of_read_number(prop, len / sizeof(u32));
737
738                 if (params[i].size == sizeof(u32))
739                         *(u32 *)dest = val;
740                 else
741                         *(u64 *)dest = val;
742
743                 if (efi_enabled(EFI_DBG))
744                         pr_info("  %s: 0x%0*llx\n", params[i].name,
745                                 params[i].size * 2, val);
746         }
747
748         return 1;
749 }
750
751 static int __init fdt_find_uefi_params(unsigned long node, const char *uname,
752                                        int depth, void *data)
753 {
754         struct param_info *info = data;
755         int i;
756
757         for (i = 0; i < ARRAY_SIZE(dt_params); i++) {
758                 const char *subnode = dt_params[i].subnode;
759
760                 if (depth != 1 || strcmp(uname, dt_params[i].uname) != 0) {
761                         info->missing = dt_params[i].params[0].name;
762                         continue;
763                 }
764
765                 if (subnode) {
766                         int err = of_get_flat_dt_subnode_by_name(node, subnode);
767
768                         if (err < 0)
769                                 return 0;
770
771                         node = err;
772                 }
773
774                 return __find_uefi_params(node, info, dt_params[i].params);
775         }
776
777         return 0;
778 }
779
780 int __init efi_get_fdt_params(struct efi_fdt_params *params)
781 {
782         struct param_info info;
783         int ret;
784
785         pr_info("Getting EFI parameters from FDT:\n");
786
787         info.found = 0;
788         info.params = params;
789
790         ret = of_scan_flat_dt(fdt_find_uefi_params, &info);
791         if (!info.found)
792                 pr_info("UEFI not found.\n");
793         else if (!ret)
794                 pr_err("Can't find '%s' in device tree!\n",
795                        info.missing);
796
797         return ret;
798 }
799 #endif /* CONFIG_EFI_PARAMS_FROM_FDT */
800
801 static __initdata char memory_type_name[][20] = {
802         "Reserved",
803         "Loader Code",
804         "Loader Data",
805         "Boot Code",
806         "Boot Data",
807         "Runtime Code",
808         "Runtime Data",
809         "Conventional Memory",
810         "Unusable Memory",
811         "ACPI Reclaim Memory",
812         "ACPI Memory NVS",
813         "Memory Mapped I/O",
814         "MMIO Port Space",
815         "PAL Code",
816         "Persistent Memory",
817 };
818
819 char * __init efi_md_typeattr_format(char *buf, size_t size,
820                                      const efi_memory_desc_t *md)
821 {
822         char *pos;
823         int type_len;
824         u64 attr;
825
826         pos = buf;
827         if (md->type >= ARRAY_SIZE(memory_type_name))
828                 type_len = snprintf(pos, size, "[type=%u", md->type);
829         else
830                 type_len = snprintf(pos, size, "[%-*s",
831                                     (int)(sizeof(memory_type_name[0]) - 1),
832                                     memory_type_name[md->type]);
833         if (type_len >= size)
834                 return buf;
835
836         pos += type_len;
837         size -= type_len;
838
839         attr = md->attribute;
840         if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
841                      EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
842                      EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
843                      EFI_MEMORY_NV |
844                      EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE))
845                 snprintf(pos, size, "|attr=0x%016llx]",
846                          (unsigned long long)attr);
847         else
848                 snprintf(pos, size,
849                          "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
850                          attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
851                          attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "",
852                          attr & EFI_MEMORY_NV      ? "NV"  : "",
853                          attr & EFI_MEMORY_XP      ? "XP"  : "",
854                          attr & EFI_MEMORY_RP      ? "RP"  : "",
855                          attr & EFI_MEMORY_WP      ? "WP"  : "",
856                          attr & EFI_MEMORY_RO      ? "RO"  : "",
857                          attr & EFI_MEMORY_UCE     ? "UCE" : "",
858                          attr & EFI_MEMORY_WB      ? "WB"  : "",
859                          attr & EFI_MEMORY_WT      ? "WT"  : "",
860                          attr & EFI_MEMORY_WC      ? "WC"  : "",
861                          attr & EFI_MEMORY_UC      ? "UC"  : "");
862         return buf;
863 }
864
865 /*
866  * IA64 has a funky EFI memory map that doesn't work the same way as
867  * other architectures.
868  */
869 #ifndef CONFIG_IA64
870 /*
871  * efi_mem_attributes - lookup memmap attributes for physical address
872  * @phys_addr: the physical address to lookup
873  *
874  * Search in the EFI memory map for the region covering
875  * @phys_addr. Returns the EFI memory attributes if the region
876  * was found in the memory map, 0 otherwise.
877  */
878 u64 efi_mem_attributes(unsigned long phys_addr)
879 {
880         efi_memory_desc_t *md;
881
882         if (!efi_enabled(EFI_MEMMAP))
883                 return 0;
884
885         for_each_efi_memory_desc(md) {
886                 if ((md->phys_addr <= phys_addr) &&
887                     (phys_addr < (md->phys_addr +
888                     (md->num_pages << EFI_PAGE_SHIFT))))
889                         return md->attribute;
890         }
891         return 0;
892 }
893
894 /*
895  * efi_mem_type - lookup memmap type for physical address
896  * @phys_addr: the physical address to lookup
897  *
898  * Search in the EFI memory map for the region covering @phys_addr.
899  * Returns the EFI memory type if the region was found in the memory
900  * map, EFI_RESERVED_TYPE (zero) otherwise.
901  */
902 int efi_mem_type(unsigned long phys_addr)
903 {
904         const efi_memory_desc_t *md;
905
906         if (!efi_enabled(EFI_MEMMAP))
907                 return -ENOTSUPP;
908
909         for_each_efi_memory_desc(md) {
910                 if ((md->phys_addr <= phys_addr) &&
911                     (phys_addr < (md->phys_addr +
912                                   (md->num_pages << EFI_PAGE_SHIFT))))
913                         return md->type;
914         }
915         return -EINVAL;
916 }
917 #endif
918
919 int efi_status_to_err(efi_status_t status)
920 {
921         int err;
922
923         switch (status) {
924         case EFI_SUCCESS:
925                 err = 0;
926                 break;
927         case EFI_INVALID_PARAMETER:
928                 err = -EINVAL;
929                 break;
930         case EFI_OUT_OF_RESOURCES:
931                 err = -ENOSPC;
932                 break;
933         case EFI_DEVICE_ERROR:
934                 err = -EIO;
935                 break;
936         case EFI_WRITE_PROTECTED:
937                 err = -EROFS;
938                 break;
939         case EFI_SECURITY_VIOLATION:
940                 err = -EACCES;
941                 break;
942         case EFI_NOT_FOUND:
943                 err = -ENOENT;
944                 break;
945         case EFI_ABORTED:
946                 err = -EINTR;
947                 break;
948         default:
949                 err = -EINVAL;
950         }
951
952         return err;
953 }
954
955 bool efi_is_table_address(unsigned long phys_addr)
956 {
957         unsigned int i;
958
959         if (phys_addr == EFI_INVALID_TABLE_ADDR)
960                 return false;
961
962         for (i = 0; i < ARRAY_SIZE(efi_tables); i++)
963                 if (*(efi_tables[i]) == phys_addr)
964                         return true;
965
966         return false;
967 }
968
969 static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock);
970 static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init;
971
972 int efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
973 {
974         struct linux_efi_memreserve *rsv;
975
976         if (!efi_memreserve_root)
977                 return -ENODEV;
978
979         rsv = kmalloc(sizeof(*rsv), GFP_ATOMIC);
980         if (!rsv)
981                 return -ENOMEM;
982
983         rsv->base = addr;
984         rsv->size = size;
985
986         spin_lock(&efi_mem_reserve_persistent_lock);
987         rsv->next = efi_memreserve_root->next;
988         efi_memreserve_root->next = __pa(rsv);
989         spin_unlock(&efi_mem_reserve_persistent_lock);
990
991         return 0;
992 }
993
994 static int __init efi_memreserve_root_init(void)
995 {
996         if (efi.mem_reserve == EFI_INVALID_TABLE_ADDR)
997                 return -ENODEV;
998
999         efi_memreserve_root = memremap(efi.mem_reserve,
1000                                        sizeof(*efi_memreserve_root),
1001                                        MEMREMAP_WB);
1002         if (!efi_memreserve_root)
1003                 return -ENOMEM;
1004         return 0;
1005 }
1006 early_initcall(efi_memreserve_root_init);
1007
1008 #ifdef CONFIG_KEXEC
1009 static int update_efi_random_seed(struct notifier_block *nb,
1010                                   unsigned long code, void *unused)
1011 {
1012         struct linux_efi_random_seed *seed;
1013         u32 size = 0;
1014
1015         if (!kexec_in_progress)
1016                 return NOTIFY_DONE;
1017
1018         seed = memremap(efi.rng_seed, sizeof(*seed), MEMREMAP_WB);
1019         if (seed != NULL) {
1020                 size = min(seed->size, EFI_RANDOM_SEED_SIZE);
1021                 memunmap(seed);
1022         } else {
1023                 pr_err("Could not map UEFI random seed!\n");
1024         }
1025         if (size > 0) {
1026                 seed = memremap(efi.rng_seed, sizeof(*seed) + size,
1027                                 MEMREMAP_WB);
1028                 if (seed != NULL) {
1029                         seed->size = size;
1030                         get_random_bytes(seed->bits, seed->size);
1031                         memunmap(seed);
1032                 } else {
1033                         pr_err("Could not map UEFI random seed!\n");
1034                 }
1035         }
1036         return NOTIFY_DONE;
1037 }
1038
1039 static struct notifier_block efi_random_seed_nb = {
1040         .notifier_call = update_efi_random_seed,
1041 };
1042
1043 static int register_update_efi_random_seed(void)
1044 {
1045         if (efi.rng_seed == EFI_INVALID_TABLE_ADDR)
1046                 return 0;
1047         return register_reboot_notifier(&efi_random_seed_nb);
1048 }
1049 late_initcall(register_update_efi_random_seed);
1050 #endif