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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * efi.c - EFI subsystem
4 *
5 * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
6 * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
7 * Copyright (C) 2013 Tom Gundersen <teg@jklm.no>
8 *
9 * This code registers /sys/firmware/efi{,/efivars} when EFI is supported,
10 * allowing the efivarfs to be mounted or the efivars module to be loaded.
11 * The existance of /sys/firmware/efi may also be used by userspace to
12 * determine that the system supports EFI.
13 */
14
15#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16
17#include <linux/kobject.h>
18#include <linux/module.h>
19#include <linux/init.h>
20#include <linux/debugfs.h>
21#include <linux/device.h>
22#include <linux/efi.h>
23#include <linux/of.h>
24#include <linux/initrd.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#include <linux/security.h>
35
36#include <asm/early_ioremap.h>
37
38struct efi __read_mostly efi = {
39 .runtime_supported_mask = EFI_RT_SUPPORTED_ALL,
40 .acpi = EFI_INVALID_TABLE_ADDR,
41 .acpi20 = EFI_INVALID_TABLE_ADDR,
42 .smbios = EFI_INVALID_TABLE_ADDR,
43 .smbios3 = EFI_INVALID_TABLE_ADDR,
44 .esrt = EFI_INVALID_TABLE_ADDR,
45 .tpm_log = EFI_INVALID_TABLE_ADDR,
46 .tpm_final_log = EFI_INVALID_TABLE_ADDR,
47#ifdef CONFIG_LOAD_UEFI_KEYS
48 .mokvar_table = EFI_INVALID_TABLE_ADDR,
49#endif
50#ifdef CONFIG_EFI_COCO_SECRET
51 .coco_secret = EFI_INVALID_TABLE_ADDR,
52#endif
53};
54EXPORT_SYMBOL(efi);
55
56unsigned long __ro_after_init efi_rng_seed = EFI_INVALID_TABLE_ADDR;
57static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR;
58static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR;
59static unsigned long __initdata initrd = EFI_INVALID_TABLE_ADDR;
60
61extern unsigned long screen_info_table;
62
63struct mm_struct efi_mm = {
64 .mm_mt = MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, efi_mm.mmap_lock),
65 .mm_users = ATOMIC_INIT(2),
66 .mm_count = ATOMIC_INIT(1),
67 .write_protect_seq = SEQCNT_ZERO(efi_mm.write_protect_seq),
68 MMAP_LOCK_INITIALIZER(efi_mm)
69 .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock),
70 .mmlist = LIST_HEAD_INIT(efi_mm.mmlist),
71 .cpu_bitmap = { [BITS_TO_LONGS(NR_CPUS)] = 0},
72};
73
74struct workqueue_struct *efi_rts_wq;
75
76static bool disable_runtime = IS_ENABLED(CONFIG_EFI_DISABLE_RUNTIME);
77static int __init setup_noefi(char *arg)
78{
79 disable_runtime = true;
80 return 0;
81}
82early_param("noefi", setup_noefi);
83
84bool efi_runtime_disabled(void)
85{
86 return disable_runtime;
87}
88
89bool __pure __efi_soft_reserve_enabled(void)
90{
91 return !efi_enabled(EFI_MEM_NO_SOFT_RESERVE);
92}
93
94static int __init parse_efi_cmdline(char *str)
95{
96 if (!str) {
97 pr_warn("need at least one option\n");
98 return -EINVAL;
99 }
100
101 if (parse_option_str(str, "debug"))
102 set_bit(EFI_DBG, &efi.flags);
103
104 if (parse_option_str(str, "noruntime"))
105 disable_runtime = true;
106
107 if (parse_option_str(str, "runtime"))
108 disable_runtime = false;
109
110 if (parse_option_str(str, "nosoftreserve"))
111 set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags);
112
113 return 0;
114}
115early_param("efi", parse_efi_cmdline);
116
117struct kobject *efi_kobj;
118
119/*
120 * Let's not leave out systab information that snuck into
121 * the efivars driver
122 * Note, do not add more fields in systab sysfs file as it breaks sysfs
123 * one value per file rule!
124 */
125static ssize_t systab_show(struct kobject *kobj,
126 struct kobj_attribute *attr, char *buf)
127{
128 char *str = buf;
129
130 if (!kobj || !buf)
131 return -EINVAL;
132
133 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
134 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
135 if (efi.acpi != EFI_INVALID_TABLE_ADDR)
136 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
137 /*
138 * If both SMBIOS and SMBIOS3 entry points are implemented, the
139 * SMBIOS3 entry point shall be preferred, so we list it first to
140 * let applications stop parsing after the first match.
141 */
142 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
143 str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
144 if (efi.smbios != EFI_INVALID_TABLE_ADDR)
145 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
146
147 if (IS_ENABLED(CONFIG_IA64) || IS_ENABLED(CONFIG_X86))
148 str = efi_systab_show_arch(str);
149
150 return str - buf;
151}
152
153static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400);
154
155static ssize_t fw_platform_size_show(struct kobject *kobj,
156 struct kobj_attribute *attr, char *buf)
157{
158 return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
159}
160
161extern __weak struct kobj_attribute efi_attr_fw_vendor;
162extern __weak struct kobj_attribute efi_attr_runtime;
163extern __weak struct kobj_attribute efi_attr_config_table;
164static struct kobj_attribute efi_attr_fw_platform_size =
165 __ATTR_RO(fw_platform_size);
166
167static struct attribute *efi_subsys_attrs[] = {
168 &efi_attr_systab.attr,
169 &efi_attr_fw_platform_size.attr,
170 &efi_attr_fw_vendor.attr,
171 &efi_attr_runtime.attr,
172 &efi_attr_config_table.attr,
173 NULL,
174};
175
176umode_t __weak efi_attr_is_visible(struct kobject *kobj, struct attribute *attr,
177 int n)
178{
179 return attr->mode;
180}
181
182static const struct attribute_group efi_subsys_attr_group = {
183 .attrs = efi_subsys_attrs,
184 .is_visible = efi_attr_is_visible,
185};
186
187static struct efivars generic_efivars;
188static struct efivar_operations generic_ops;
189
190static int generic_ops_register(void)
191{
192 generic_ops.get_variable = efi.get_variable;
193 generic_ops.get_next_variable = efi.get_next_variable;
194 generic_ops.query_variable_store = efi_query_variable_store;
195
196 if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE)) {
197 generic_ops.set_variable = efi.set_variable;
198 generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
199 }
200 return efivars_register(&generic_efivars, &generic_ops, efi_kobj);
201}
202
203static void generic_ops_unregister(void)
204{
205 efivars_unregister(&generic_efivars);
206}
207
208#ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS
209#define EFIVAR_SSDT_NAME_MAX 16UL
210static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
211static int __init efivar_ssdt_setup(char *str)
212{
213 int ret = security_locked_down(LOCKDOWN_ACPI_TABLES);
214
215 if (ret)
216 return ret;
217
218 if (strlen(str) < sizeof(efivar_ssdt))
219 memcpy(efivar_ssdt, str, strlen(str));
220 else
221 pr_warn("efivar_ssdt: name too long: %s\n", str);
222 return 1;
223}
224__setup("efivar_ssdt=", efivar_ssdt_setup);
225
226static __init int efivar_ssdt_load(void)
227{
228 unsigned long name_size = 256;
229 efi_char16_t *name = NULL;
230 efi_status_t status;
231 efi_guid_t guid;
232
233 if (!efivar_ssdt[0])
234 return 0;
235
236 name = kzalloc(name_size, GFP_KERNEL);
237 if (!name)
238 return -ENOMEM;
239
240 for (;;) {
241 char utf8_name[EFIVAR_SSDT_NAME_MAX];
242 unsigned long data_size = 0;
243 void *data;
244 int limit;
245
246 status = efi.get_next_variable(&name_size, name, &guid);
247 if (status == EFI_NOT_FOUND) {
248 break;
249 } else if (status == EFI_BUFFER_TOO_SMALL) {
250 name = krealloc(name, name_size, GFP_KERNEL);
251 if (!name)
252 return -ENOMEM;
253 continue;
254 }
255
256 limit = min(EFIVAR_SSDT_NAME_MAX, name_size);
257 ucs2_as_utf8(utf8_name, name, limit - 1);
258 if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
259 continue;
260
261 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt, &guid);
262
263 status = efi.get_variable(name, &guid, NULL, &data_size, NULL);
264 if (status != EFI_BUFFER_TOO_SMALL || !data_size)
265 return -EIO;
266
267 data = kmalloc(data_size, GFP_KERNEL);
268 if (!data)
269 return -ENOMEM;
270
271 status = efi.get_variable(name, &guid, NULL, &data_size, data);
272 if (status == EFI_SUCCESS) {
273 acpi_status ret = acpi_load_table(data, NULL);
274 if (ret)
275 pr_err("failed to load table: %u\n", ret);
276 else
277 continue;
278 } else {
279 pr_err("failed to get var data: 0x%lx\n", status);
280 }
281 kfree(data);
282 }
283 return 0;
284}
285#else
286static inline int efivar_ssdt_load(void) { return 0; }
287#endif
288
289#ifdef CONFIG_DEBUG_FS
290
291#define EFI_DEBUGFS_MAX_BLOBS 32
292
293static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS];
294
295static void __init efi_debugfs_init(void)
296{
297 struct dentry *efi_debugfs;
298 efi_memory_desc_t *md;
299 char name[32];
300 int type_count[EFI_BOOT_SERVICES_DATA + 1] = {};
301 int i = 0;
302
303 efi_debugfs = debugfs_create_dir("efi", NULL);
304 if (IS_ERR_OR_NULL(efi_debugfs))
305 return;
306
307 for_each_efi_memory_desc(md) {
308 switch (md->type) {
309 case EFI_BOOT_SERVICES_CODE:
310 snprintf(name, sizeof(name), "boot_services_code%d",
311 type_count[md->type]++);
312 break;
313 case EFI_BOOT_SERVICES_DATA:
314 snprintf(name, sizeof(name), "boot_services_data%d",
315 type_count[md->type]++);
316 break;
317 default:
318 continue;
319 }
320
321 if (i >= EFI_DEBUGFS_MAX_BLOBS) {
322 pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n",
323 EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS);
324 break;
325 }
326
327 debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT;
328 debugfs_blob[i].data = memremap(md->phys_addr,
329 debugfs_blob[i].size,
330 MEMREMAP_WB);
331 if (!debugfs_blob[i].data)
332 continue;
333
334 debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]);
335 i++;
336 }
337}
338#else
339static inline void efi_debugfs_init(void) {}
340#endif
341
342static void refresh_nv_rng_seed(struct work_struct *work)
343{
344 u8 seed[EFI_RANDOM_SEED_SIZE];
345
346 get_random_bytes(seed, sizeof(seed));
347 efi.set_variable(L"RandomSeed", &LINUX_EFI_RANDOM_SEED_TABLE_GUID,
348 EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS |
349 EFI_VARIABLE_RUNTIME_ACCESS, sizeof(seed), seed);
350 memzero_explicit(seed, sizeof(seed));
351}
352static int refresh_nv_rng_seed_notification(struct notifier_block *nb, unsigned long action, void *data)
353{
354 static DECLARE_WORK(work, refresh_nv_rng_seed);
355 schedule_work(&work);
356 return NOTIFY_DONE;
357}
358static struct notifier_block refresh_nv_rng_seed_nb = { .notifier_call = refresh_nv_rng_seed_notification };
359
360/*
361 * We register the efi subsystem with the firmware subsystem and the
362 * efivars subsystem with the efi subsystem, if the system was booted with
363 * EFI.
364 */
365static int __init efisubsys_init(void)
366{
367 int error;
368
369 if (!efi_enabled(EFI_RUNTIME_SERVICES))
370 efi.runtime_supported_mask = 0;
371
372 if (!efi_enabled(EFI_BOOT))
373 return 0;
374
375 if (efi.runtime_supported_mask) {
376 /*
377 * Since we process only one efi_runtime_service() at a time, an
378 * ordered workqueue (which creates only one execution context)
379 * should suffice for all our needs.
380 */
381 efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0);
382 if (!efi_rts_wq) {
383 pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n");
384 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
385 efi.runtime_supported_mask = 0;
386 return 0;
387 }
388 }
389
390 if (efi_rt_services_supported(EFI_RT_SUPPORTED_TIME_SERVICES))
391 platform_device_register_simple("rtc-efi", 0, NULL, 0);
392
393 /* We register the efi directory at /sys/firmware/efi */
394 efi_kobj = kobject_create_and_add("efi", firmware_kobj);
395 if (!efi_kobj) {
396 pr_err("efi: Firmware registration failed.\n");
397 error = -ENOMEM;
398 goto err_destroy_wq;
399 }
400
401 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
402 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) {
403 error = generic_ops_register();
404 if (error)
405 goto err_put;
406 efivar_ssdt_load();
407 platform_device_register_simple("efivars", 0, NULL, 0);
408 }
409
410 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
411 if (error) {
412 pr_err("efi: Sysfs attribute export failed with error %d.\n",
413 error);
414 goto err_unregister;
415 }
416
417 /* and the standard mountpoint for efivarfs */
418 error = sysfs_create_mount_point(efi_kobj, "efivars");
419 if (error) {
420 pr_err("efivars: Subsystem registration failed.\n");
421 goto err_remove_group;
422 }
423
424 if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS))
425 efi_debugfs_init();
426
427#ifdef CONFIG_EFI_COCO_SECRET
428 if (efi.coco_secret != EFI_INVALID_TABLE_ADDR)
429 platform_device_register_simple("efi_secret", 0, NULL, 0);
430#endif
431
432 if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE))
433 execute_with_initialized_rng(&refresh_nv_rng_seed_nb);
434
435 return 0;
436
437err_remove_group:
438 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
439err_unregister:
440 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
441 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME))
442 generic_ops_unregister();
443err_put:
444 kobject_put(efi_kobj);
445 efi_kobj = NULL;
446err_destroy_wq:
447 if (efi_rts_wq)
448 destroy_workqueue(efi_rts_wq);
449
450 return error;
451}
452
453subsys_initcall(efisubsys_init);
454
455void __init efi_find_mirror(void)
456{
457 efi_memory_desc_t *md;
458 u64 mirror_size = 0, total_size = 0;
459
460 if (!efi_enabled(EFI_MEMMAP))
461 return;
462
463 for_each_efi_memory_desc(md) {
464 unsigned long long start = md->phys_addr;
465 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
466
467 total_size += size;
468 if (md->attribute & EFI_MEMORY_MORE_RELIABLE) {
469 memblock_mark_mirror(start, size);
470 mirror_size += size;
471 }
472 }
473 if (mirror_size)
474 pr_info("Memory: %lldM/%lldM mirrored memory\n",
475 mirror_size>>20, total_size>>20);
476}
477
478/*
479 * Find the efi memory descriptor for a given physical address. Given a
480 * physical address, determine if it exists within an EFI Memory Map entry,
481 * and if so, populate the supplied memory descriptor with the appropriate
482 * data.
483 */
484int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
485{
486 efi_memory_desc_t *md;
487
488 if (!efi_enabled(EFI_MEMMAP)) {
489 pr_err_once("EFI_MEMMAP is not enabled.\n");
490 return -EINVAL;
491 }
492
493 if (!out_md) {
494 pr_err_once("out_md is null.\n");
495 return -EINVAL;
496 }
497
498 for_each_efi_memory_desc(md) {
499 u64 size;
500 u64 end;
501
502 size = md->num_pages << EFI_PAGE_SHIFT;
503 end = md->phys_addr + size;
504 if (phys_addr >= md->phys_addr && phys_addr < end) {
505 memcpy(out_md, md, sizeof(*out_md));
506 return 0;
507 }
508 }
509 return -ENOENT;
510}
511
512/*
513 * Calculate the highest address of an efi memory descriptor.
514 */
515u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
516{
517 u64 size = md->num_pages << EFI_PAGE_SHIFT;
518 u64 end = md->phys_addr + size;
519 return end;
520}
521
522void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {}
523
524/**
525 * efi_mem_reserve - Reserve an EFI memory region
526 * @addr: Physical address to reserve
527 * @size: Size of reservation
528 *
529 * Mark a region as reserved from general kernel allocation and
530 * prevent it being released by efi_free_boot_services().
531 *
532 * This function should be called drivers once they've parsed EFI
533 * configuration tables to figure out where their data lives, e.g.
534 * efi_esrt_init().
535 */
536void __init efi_mem_reserve(phys_addr_t addr, u64 size)
537{
538 if (!memblock_is_region_reserved(addr, size))
539 memblock_reserve(addr, size);
540
541 /*
542 * Some architectures (x86) reserve all boot services ranges
543 * until efi_free_boot_services() because of buggy firmware
544 * implementations. This means the above memblock_reserve() is
545 * superfluous on x86 and instead what it needs to do is
546 * ensure the @start, @size is not freed.
547 */
548 efi_arch_mem_reserve(addr, size);
549}
550
551static const efi_config_table_type_t common_tables[] __initconst = {
552 {ACPI_20_TABLE_GUID, &efi.acpi20, "ACPI 2.0" },
553 {ACPI_TABLE_GUID, &efi.acpi, "ACPI" },
554 {SMBIOS_TABLE_GUID, &efi.smbios, "SMBIOS" },
555 {SMBIOS3_TABLE_GUID, &efi.smbios3, "SMBIOS 3.0" },
556 {EFI_SYSTEM_RESOURCE_TABLE_GUID, &efi.esrt, "ESRT" },
557 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, &efi_mem_attr_table, "MEMATTR" },
558 {LINUX_EFI_RANDOM_SEED_TABLE_GUID, &efi_rng_seed, "RNG" },
559 {LINUX_EFI_TPM_EVENT_LOG_GUID, &efi.tpm_log, "TPMEventLog" },
560 {LINUX_EFI_TPM_FINAL_LOG_GUID, &efi.tpm_final_log, "TPMFinalLog" },
561 {LINUX_EFI_MEMRESERVE_TABLE_GUID, &mem_reserve, "MEMRESERVE" },
562 {LINUX_EFI_INITRD_MEDIA_GUID, &initrd, "INITRD" },
563 {EFI_RT_PROPERTIES_TABLE_GUID, &rt_prop, "RTPROP" },
564#ifdef CONFIG_EFI_RCI2_TABLE
565 {DELLEMC_EFI_RCI2_TABLE_GUID, &rci2_table_phys },
566#endif
567#ifdef CONFIG_LOAD_UEFI_KEYS
568 {LINUX_EFI_MOK_VARIABLE_TABLE_GUID, &efi.mokvar_table, "MOKvar" },
569#endif
570#ifdef CONFIG_EFI_COCO_SECRET
571 {LINUX_EFI_COCO_SECRET_AREA_GUID, &efi.coco_secret, "CocoSecret" },
572#endif
573#ifdef CONFIG_EFI_GENERIC_STUB
574 {LINUX_EFI_SCREEN_INFO_TABLE_GUID, &screen_info_table },
575#endif
576 {},
577};
578
579static __init int match_config_table(const efi_guid_t *guid,
580 unsigned long table,
581 const efi_config_table_type_t *table_types)
582{
583 int i;
584
585 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
586 if (!efi_guidcmp(*guid, table_types[i].guid)) {
587 *(table_types[i].ptr) = table;
588 if (table_types[i].name[0])
589 pr_cont("%s=0x%lx ",
590 table_types[i].name, table);
591 return 1;
592 }
593 }
594
595 return 0;
596}
597
598int __init efi_config_parse_tables(const efi_config_table_t *config_tables,
599 int count,
600 const efi_config_table_type_t *arch_tables)
601{
602 const efi_config_table_64_t *tbl64 = (void *)config_tables;
603 const efi_config_table_32_t *tbl32 = (void *)config_tables;
604 const efi_guid_t *guid;
605 unsigned long table;
606 int i;
607
608 pr_info("");
609 for (i = 0; i < count; i++) {
610 if (!IS_ENABLED(CONFIG_X86)) {
611 guid = &config_tables[i].guid;
612 table = (unsigned long)config_tables[i].table;
613 } else if (efi_enabled(EFI_64BIT)) {
614 guid = &tbl64[i].guid;
615 table = tbl64[i].table;
616
617 if (IS_ENABLED(CONFIG_X86_32) &&
618 tbl64[i].table > U32_MAX) {
619 pr_cont("\n");
620 pr_err("Table located above 4GB, disabling EFI.\n");
621 return -EINVAL;
622 }
623 } else {
624 guid = &tbl32[i].guid;
625 table = tbl32[i].table;
626 }
627
628 if (!match_config_table(guid, table, common_tables) && arch_tables)
629 match_config_table(guid, table, arch_tables);
630 }
631 pr_cont("\n");
632 set_bit(EFI_CONFIG_TABLES, &efi.flags);
633
634 if (efi_rng_seed != EFI_INVALID_TABLE_ADDR) {
635 struct linux_efi_random_seed *seed;
636 u32 size = 0;
637
638 seed = early_memremap(efi_rng_seed, sizeof(*seed));
639 if (seed != NULL) {
640 size = min_t(u32, seed->size, SZ_1K); // sanity check
641 early_memunmap(seed, sizeof(*seed));
642 } else {
643 pr_err("Could not map UEFI random seed!\n");
644 }
645 if (size > 0) {
646 seed = early_memremap(efi_rng_seed,
647 sizeof(*seed) + size);
648 if (seed != NULL) {
649 add_bootloader_randomness(seed->bits, size);
650 memzero_explicit(seed->bits, size);
651 early_memunmap(seed, sizeof(*seed) + size);
652 } else {
653 pr_err("Could not map UEFI random seed!\n");
654 }
655 }
656 }
657
658 if (!IS_ENABLED(CONFIG_X86_32) && efi_enabled(EFI_MEMMAP))
659 efi_memattr_init();
660
661 efi_tpm_eventlog_init();
662
663 if (mem_reserve != EFI_INVALID_TABLE_ADDR) {
664 unsigned long prsv = mem_reserve;
665
666 while (prsv) {
667 struct linux_efi_memreserve *rsv;
668 u8 *p;
669
670 /*
671 * Just map a full page: that is what we will get
672 * anyway, and it permits us to map the entire entry
673 * before knowing its size.
674 */
675 p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE),
676 PAGE_SIZE);
677 if (p == NULL) {
678 pr_err("Could not map UEFI memreserve entry!\n");
679 return -ENOMEM;
680 }
681
682 rsv = (void *)(p + prsv % PAGE_SIZE);
683
684 /* reserve the entry itself */
685 memblock_reserve(prsv,
686 struct_size(rsv, entry, rsv->size));
687
688 for (i = 0; i < atomic_read(&rsv->count); i++) {
689 memblock_reserve(rsv->entry[i].base,
690 rsv->entry[i].size);
691 }
692
693 prsv = rsv->next;
694 early_memunmap(p, PAGE_SIZE);
695 }
696 }
697
698 if (rt_prop != EFI_INVALID_TABLE_ADDR) {
699 efi_rt_properties_table_t *tbl;
700
701 tbl = early_memremap(rt_prop, sizeof(*tbl));
702 if (tbl) {
703 efi.runtime_supported_mask &= tbl->runtime_services_supported;
704 early_memunmap(tbl, sizeof(*tbl));
705 }
706 }
707
708 if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) &&
709 initrd != EFI_INVALID_TABLE_ADDR && phys_initrd_size == 0) {
710 struct linux_efi_initrd *tbl;
711
712 tbl = early_memremap(initrd, sizeof(*tbl));
713 if (tbl) {
714 phys_initrd_start = tbl->base;
715 phys_initrd_size = tbl->size;
716 early_memunmap(tbl, sizeof(*tbl));
717 }
718 }
719
720 return 0;
721}
722
723int __init efi_systab_check_header(const efi_table_hdr_t *systab_hdr,
724 int min_major_version)
725{
726 if (systab_hdr->signature != EFI_SYSTEM_TABLE_SIGNATURE) {
727 pr_err("System table signature incorrect!\n");
728 return -EINVAL;
729 }
730
731 if ((systab_hdr->revision >> 16) < min_major_version)
732 pr_err("Warning: System table version %d.%02d, expected %d.00 or greater!\n",
733 systab_hdr->revision >> 16,
734 systab_hdr->revision & 0xffff,
735 min_major_version);
736
737 return 0;
738}
739
740#ifndef CONFIG_IA64
741static const efi_char16_t *__init map_fw_vendor(unsigned long fw_vendor,
742 size_t size)
743{
744 const efi_char16_t *ret;
745
746 ret = early_memremap_ro(fw_vendor, size);
747 if (!ret)
748 pr_err("Could not map the firmware vendor!\n");
749 return ret;
750}
751
752static void __init unmap_fw_vendor(const void *fw_vendor, size_t size)
753{
754 early_memunmap((void *)fw_vendor, size);
755}
756#else
757#define map_fw_vendor(p, s) __va(p)
758#define unmap_fw_vendor(v, s)
759#endif
760
761void __init efi_systab_report_header(const efi_table_hdr_t *systab_hdr,
762 unsigned long fw_vendor)
763{
764 char vendor[100] = "unknown";
765 const efi_char16_t *c16;
766 size_t i;
767
768 c16 = map_fw_vendor(fw_vendor, sizeof(vendor) * sizeof(efi_char16_t));
769 if (c16) {
770 for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i)
771 vendor[i] = c16[i];
772 vendor[i] = '\0';
773
774 unmap_fw_vendor(c16, sizeof(vendor) * sizeof(efi_char16_t));
775 }
776
777 pr_info("EFI v%u.%.02u by %s\n",
778 systab_hdr->revision >> 16,
779 systab_hdr->revision & 0xffff,
780 vendor);
781
782 if (IS_ENABLED(CONFIG_X86_64) &&
783 systab_hdr->revision > EFI_1_10_SYSTEM_TABLE_REVISION &&
784 !strcmp(vendor, "Apple")) {
785 pr_info("Apple Mac detected, using EFI v1.10 runtime services only\n");
786 efi.runtime_version = EFI_1_10_SYSTEM_TABLE_REVISION;
787 }
788}
789
790static __initdata char memory_type_name[][13] = {
791 "Reserved",
792 "Loader Code",
793 "Loader Data",
794 "Boot Code",
795 "Boot Data",
796 "Runtime Code",
797 "Runtime Data",
798 "Conventional",
799 "Unusable",
800 "ACPI Reclaim",
801 "ACPI Mem NVS",
802 "MMIO",
803 "MMIO Port",
804 "PAL Code",
805 "Persistent",
806};
807
808char * __init efi_md_typeattr_format(char *buf, size_t size,
809 const efi_memory_desc_t *md)
810{
811 char *pos;
812 int type_len;
813 u64 attr;
814
815 pos = buf;
816 if (md->type >= ARRAY_SIZE(memory_type_name))
817 type_len = snprintf(pos, size, "[type=%u", md->type);
818 else
819 type_len = snprintf(pos, size, "[%-*s",
820 (int)(sizeof(memory_type_name[0]) - 1),
821 memory_type_name[md->type]);
822 if (type_len >= size)
823 return buf;
824
825 pos += type_len;
826 size -= type_len;
827
828 attr = md->attribute;
829 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
830 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
831 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
832 EFI_MEMORY_NV | EFI_MEMORY_SP | EFI_MEMORY_CPU_CRYPTO |
833 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE))
834 snprintf(pos, size, "|attr=0x%016llx]",
835 (unsigned long long)attr);
836 else
837 snprintf(pos, size,
838 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
839 attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
840 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "",
841 attr & EFI_MEMORY_CPU_CRYPTO ? "CC" : "",
842 attr & EFI_MEMORY_SP ? "SP" : "",
843 attr & EFI_MEMORY_NV ? "NV" : "",
844 attr & EFI_MEMORY_XP ? "XP" : "",
845 attr & EFI_MEMORY_RP ? "RP" : "",
846 attr & EFI_MEMORY_WP ? "WP" : "",
847 attr & EFI_MEMORY_RO ? "RO" : "",
848 attr & EFI_MEMORY_UCE ? "UCE" : "",
849 attr & EFI_MEMORY_WB ? "WB" : "",
850 attr & EFI_MEMORY_WT ? "WT" : "",
851 attr & EFI_MEMORY_WC ? "WC" : "",
852 attr & EFI_MEMORY_UC ? "UC" : "");
853 return buf;
854}
855
856/*
857 * IA64 has a funky EFI memory map that doesn't work the same way as
858 * other architectures.
859 */
860#ifndef CONFIG_IA64
861/*
862 * efi_mem_attributes - lookup memmap attributes for physical address
863 * @phys_addr: the physical address to lookup
864 *
865 * Search in the EFI memory map for the region covering
866 * @phys_addr. Returns the EFI memory attributes if the region
867 * was found in the memory map, 0 otherwise.
868 */
869u64 efi_mem_attributes(unsigned long phys_addr)
870{
871 efi_memory_desc_t *md;
872
873 if (!efi_enabled(EFI_MEMMAP))
874 return 0;
875
876 for_each_efi_memory_desc(md) {
877 if ((md->phys_addr <= phys_addr) &&
878 (phys_addr < (md->phys_addr +
879 (md->num_pages << EFI_PAGE_SHIFT))))
880 return md->attribute;
881 }
882 return 0;
883}
884
885/*
886 * efi_mem_type - lookup memmap type for physical address
887 * @phys_addr: the physical address to lookup
888 *
889 * Search in the EFI memory map for the region covering @phys_addr.
890 * Returns the EFI memory type if the region was found in the memory
891 * map, -EINVAL otherwise.
892 */
893int efi_mem_type(unsigned long phys_addr)
894{
895 const efi_memory_desc_t *md;
896
897 if (!efi_enabled(EFI_MEMMAP))
898 return -ENOTSUPP;
899
900 for_each_efi_memory_desc(md) {
901 if ((md->phys_addr <= phys_addr) &&
902 (phys_addr < (md->phys_addr +
903 (md->num_pages << EFI_PAGE_SHIFT))))
904 return md->type;
905 }
906 return -EINVAL;
907}
908#endif
909
910int efi_status_to_err(efi_status_t status)
911{
912 int err;
913
914 switch (status) {
915 case EFI_SUCCESS:
916 err = 0;
917 break;
918 case EFI_INVALID_PARAMETER:
919 err = -EINVAL;
920 break;
921 case EFI_OUT_OF_RESOURCES:
922 err = -ENOSPC;
923 break;
924 case EFI_DEVICE_ERROR:
925 err = -EIO;
926 break;
927 case EFI_WRITE_PROTECTED:
928 err = -EROFS;
929 break;
930 case EFI_SECURITY_VIOLATION:
931 err = -EACCES;
932 break;
933 case EFI_NOT_FOUND:
934 err = -ENOENT;
935 break;
936 case EFI_ABORTED:
937 err = -EINTR;
938 break;
939 default:
940 err = -EINVAL;
941 }
942
943 return err;
944}
945EXPORT_SYMBOL_GPL(efi_status_to_err);
946
947static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock);
948static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init;
949
950static int __init efi_memreserve_map_root(void)
951{
952 if (mem_reserve == EFI_INVALID_TABLE_ADDR)
953 return -ENODEV;
954
955 efi_memreserve_root = memremap(mem_reserve,
956 sizeof(*efi_memreserve_root),
957 MEMREMAP_WB);
958 if (WARN_ON_ONCE(!efi_memreserve_root))
959 return -ENOMEM;
960 return 0;
961}
962
963static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size)
964{
965 struct resource *res, *parent;
966 int ret;
967
968 res = kzalloc(sizeof(struct resource), GFP_ATOMIC);
969 if (!res)
970 return -ENOMEM;
971
972 res->name = "reserved";
973 res->flags = IORESOURCE_MEM;
974 res->start = addr;
975 res->end = addr + size - 1;
976
977 /* we expect a conflict with a 'System RAM' region */
978 parent = request_resource_conflict(&iomem_resource, res);
979 ret = parent ? request_resource(parent, res) : 0;
980
981 /*
982 * Given that efi_mem_reserve_iomem() can be called at any
983 * time, only call memblock_reserve() if the architecture
984 * keeps the infrastructure around.
985 */
986 if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK) && !ret)
987 memblock_reserve(addr, size);
988
989 return ret;
990}
991
992int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
993{
994 struct linux_efi_memreserve *rsv;
995 unsigned long prsv;
996 int rc, index;
997
998 if (efi_memreserve_root == (void *)ULONG_MAX)
999 return -ENODEV;
1000
1001 if (!efi_memreserve_root) {
1002 rc = efi_memreserve_map_root();
1003 if (rc)
1004 return rc;
1005 }
1006
1007 /* first try to find a slot in an existing linked list entry */
1008 for (prsv = efi_memreserve_root->next; prsv; ) {
1009 rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB);
1010 if (!rsv)
1011 return -ENOMEM;
1012 index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size);
1013 if (index < rsv->size) {
1014 rsv->entry[index].base = addr;
1015 rsv->entry[index].size = size;
1016
1017 memunmap(rsv);
1018 return efi_mem_reserve_iomem(addr, size);
1019 }
1020 prsv = rsv->next;
1021 memunmap(rsv);
1022 }
1023
1024 /* no slot found - allocate a new linked list entry */
1025 rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC);
1026 if (!rsv)
1027 return -ENOMEM;
1028
1029 rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K);
1030 if (rc) {
1031 free_page((unsigned long)rsv);
1032 return rc;
1033 }
1034
1035 /*
1036 * The memremap() call above assumes that a linux_efi_memreserve entry
1037 * never crosses a page boundary, so let's ensure that this remains true
1038 * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by
1039 * using SZ_4K explicitly in the size calculation below.
1040 */
1041 rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K);
1042 atomic_set(&rsv->count, 1);
1043 rsv->entry[0].base = addr;
1044 rsv->entry[0].size = size;
1045
1046 spin_lock(&efi_mem_reserve_persistent_lock);
1047 rsv->next = efi_memreserve_root->next;
1048 efi_memreserve_root->next = __pa(rsv);
1049 spin_unlock(&efi_mem_reserve_persistent_lock);
1050
1051 return efi_mem_reserve_iomem(addr, size);
1052}
1053
1054static int __init efi_memreserve_root_init(void)
1055{
1056 if (efi_memreserve_root)
1057 return 0;
1058 if (efi_memreserve_map_root())
1059 efi_memreserve_root = (void *)ULONG_MAX;
1060 return 0;
1061}
1062early_initcall(efi_memreserve_root_init);
1063
1064#ifdef CONFIG_KEXEC
1065static int update_efi_random_seed(struct notifier_block *nb,
1066 unsigned long code, void *unused)
1067{
1068 struct linux_efi_random_seed *seed;
1069 u32 size = 0;
1070
1071 if (!kexec_in_progress)
1072 return NOTIFY_DONE;
1073
1074 seed = memremap(efi_rng_seed, sizeof(*seed), MEMREMAP_WB);
1075 if (seed != NULL) {
1076 size = min(seed->size, EFI_RANDOM_SEED_SIZE);
1077 memunmap(seed);
1078 } else {
1079 pr_err("Could not map UEFI random seed!\n");
1080 }
1081 if (size > 0) {
1082 seed = memremap(efi_rng_seed, sizeof(*seed) + size,
1083 MEMREMAP_WB);
1084 if (seed != NULL) {
1085 seed->size = size;
1086 get_random_bytes(seed->bits, seed->size);
1087 memunmap(seed);
1088 } else {
1089 pr_err("Could not map UEFI random seed!\n");
1090 }
1091 }
1092 return NOTIFY_DONE;
1093}
1094
1095static struct notifier_block efi_random_seed_nb = {
1096 .notifier_call = update_efi_random_seed,
1097};
1098
1099static int __init register_update_efi_random_seed(void)
1100{
1101 if (efi_rng_seed == EFI_INVALID_TABLE_ADDR)
1102 return 0;
1103 return register_reboot_notifier(&efi_random_seed_nb);
1104}
1105late_initcall(register_update_efi_random_seed);
1106#endif
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/platform_device.h>
27
28#include <asm/early_ioremap.h>
29
30struct efi __read_mostly efi = {
31 .mps = EFI_INVALID_TABLE_ADDR,
32 .acpi = EFI_INVALID_TABLE_ADDR,
33 .acpi20 = EFI_INVALID_TABLE_ADDR,
34 .smbios = EFI_INVALID_TABLE_ADDR,
35 .smbios3 = EFI_INVALID_TABLE_ADDR,
36 .sal_systab = EFI_INVALID_TABLE_ADDR,
37 .boot_info = EFI_INVALID_TABLE_ADDR,
38 .hcdp = EFI_INVALID_TABLE_ADDR,
39 .uga = EFI_INVALID_TABLE_ADDR,
40 .uv_systab = EFI_INVALID_TABLE_ADDR,
41 .fw_vendor = EFI_INVALID_TABLE_ADDR,
42 .runtime = EFI_INVALID_TABLE_ADDR,
43 .config_table = EFI_INVALID_TABLE_ADDR,
44 .esrt = EFI_INVALID_TABLE_ADDR,
45 .properties_table = EFI_INVALID_TABLE_ADDR,
46};
47EXPORT_SYMBOL(efi);
48
49static bool disable_runtime;
50static int __init setup_noefi(char *arg)
51{
52 disable_runtime = true;
53 return 0;
54}
55early_param("noefi", setup_noefi);
56
57bool efi_runtime_disabled(void)
58{
59 return disable_runtime;
60}
61
62static int __init parse_efi_cmdline(char *str)
63{
64 if (!str) {
65 pr_warn("need at least one option\n");
66 return -EINVAL;
67 }
68
69 if (parse_option_str(str, "debug"))
70 set_bit(EFI_DBG, &efi.flags);
71
72 if (parse_option_str(str, "noruntime"))
73 disable_runtime = true;
74
75 return 0;
76}
77early_param("efi", parse_efi_cmdline);
78
79struct kobject *efi_kobj;
80
81/*
82 * Let's not leave out systab information that snuck into
83 * the efivars driver
84 */
85static ssize_t systab_show(struct kobject *kobj,
86 struct kobj_attribute *attr, char *buf)
87{
88 char *str = buf;
89
90 if (!kobj || !buf)
91 return -EINVAL;
92
93 if (efi.mps != EFI_INVALID_TABLE_ADDR)
94 str += sprintf(str, "MPS=0x%lx\n", efi.mps);
95 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
96 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
97 if (efi.acpi != EFI_INVALID_TABLE_ADDR)
98 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
99 /*
100 * If both SMBIOS and SMBIOS3 entry points are implemented, the
101 * SMBIOS3 entry point shall be preferred, so we list it first to
102 * let applications stop parsing after the first match.
103 */
104 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
105 str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
106 if (efi.smbios != EFI_INVALID_TABLE_ADDR)
107 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
108 if (efi.hcdp != EFI_INVALID_TABLE_ADDR)
109 str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp);
110 if (efi.boot_info != EFI_INVALID_TABLE_ADDR)
111 str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info);
112 if (efi.uga != EFI_INVALID_TABLE_ADDR)
113 str += sprintf(str, "UGA=0x%lx\n", efi.uga);
114
115 return str - buf;
116}
117
118static struct kobj_attribute efi_attr_systab =
119 __ATTR(systab, 0400, systab_show, NULL);
120
121#define EFI_FIELD(var) efi.var
122
123#define EFI_ATTR_SHOW(name) \
124static ssize_t name##_show(struct kobject *kobj, \
125 struct kobj_attribute *attr, char *buf) \
126{ \
127 return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \
128}
129
130EFI_ATTR_SHOW(fw_vendor);
131EFI_ATTR_SHOW(runtime);
132EFI_ATTR_SHOW(config_table);
133
134static ssize_t fw_platform_size_show(struct kobject *kobj,
135 struct kobj_attribute *attr, char *buf)
136{
137 return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
138}
139
140static struct kobj_attribute efi_attr_fw_vendor = __ATTR_RO(fw_vendor);
141static struct kobj_attribute efi_attr_runtime = __ATTR_RO(runtime);
142static struct kobj_attribute efi_attr_config_table = __ATTR_RO(config_table);
143static struct kobj_attribute efi_attr_fw_platform_size =
144 __ATTR_RO(fw_platform_size);
145
146static struct attribute *efi_subsys_attrs[] = {
147 &efi_attr_systab.attr,
148 &efi_attr_fw_vendor.attr,
149 &efi_attr_runtime.attr,
150 &efi_attr_config_table.attr,
151 &efi_attr_fw_platform_size.attr,
152 NULL,
153};
154
155static umode_t efi_attr_is_visible(struct kobject *kobj,
156 struct attribute *attr, int n)
157{
158 if (attr == &efi_attr_fw_vendor.attr) {
159 if (efi_enabled(EFI_PARAVIRT) ||
160 efi.fw_vendor == EFI_INVALID_TABLE_ADDR)
161 return 0;
162 } else if (attr == &efi_attr_runtime.attr) {
163 if (efi.runtime == EFI_INVALID_TABLE_ADDR)
164 return 0;
165 } else if (attr == &efi_attr_config_table.attr) {
166 if (efi.config_table == EFI_INVALID_TABLE_ADDR)
167 return 0;
168 }
169
170 return attr->mode;
171}
172
173static struct attribute_group efi_subsys_attr_group = {
174 .attrs = efi_subsys_attrs,
175 .is_visible = efi_attr_is_visible,
176};
177
178static struct efivars generic_efivars;
179static struct efivar_operations generic_ops;
180
181static int generic_ops_register(void)
182{
183 generic_ops.get_variable = efi.get_variable;
184 generic_ops.set_variable = efi.set_variable;
185 generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
186 generic_ops.get_next_variable = efi.get_next_variable;
187 generic_ops.query_variable_store = efi_query_variable_store;
188
189 return efivars_register(&generic_efivars, &generic_ops, efi_kobj);
190}
191
192static void generic_ops_unregister(void)
193{
194 efivars_unregister(&generic_efivars);
195}
196
197/*
198 * We register the efi subsystem with the firmware subsystem and the
199 * efivars subsystem with the efi subsystem, if the system was booted with
200 * EFI.
201 */
202static int __init efisubsys_init(void)
203{
204 int error;
205
206 if (!efi_enabled(EFI_BOOT))
207 return 0;
208
209 /* We register the efi directory at /sys/firmware/efi */
210 efi_kobj = kobject_create_and_add("efi", firmware_kobj);
211 if (!efi_kobj) {
212 pr_err("efi: Firmware registration failed.\n");
213 return -ENOMEM;
214 }
215
216 error = generic_ops_register();
217 if (error)
218 goto err_put;
219
220 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
221 if (error) {
222 pr_err("efi: Sysfs attribute export failed with error %d.\n",
223 error);
224 goto err_unregister;
225 }
226
227 error = efi_runtime_map_init(efi_kobj);
228 if (error)
229 goto err_remove_group;
230
231 /* and the standard mountpoint for efivarfs */
232 error = sysfs_create_mount_point(efi_kobj, "efivars");
233 if (error) {
234 pr_err("efivars: Subsystem registration failed.\n");
235 goto err_remove_group;
236 }
237
238 return 0;
239
240err_remove_group:
241 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
242err_unregister:
243 generic_ops_unregister();
244err_put:
245 kobject_put(efi_kobj);
246 return error;
247}
248
249subsys_initcall(efisubsys_init);
250
251/*
252 * Find the efi memory descriptor for a given physical address. Given a
253 * physicall address, determine if it exists within an EFI Memory Map entry,
254 * and if so, populate the supplied memory descriptor with the appropriate
255 * data.
256 */
257int __init efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
258{
259 struct efi_memory_map *map = efi.memmap;
260 phys_addr_t p, e;
261
262 if (!efi_enabled(EFI_MEMMAP)) {
263 pr_err_once("EFI_MEMMAP is not enabled.\n");
264 return -EINVAL;
265 }
266
267 if (!map) {
268 pr_err_once("efi.memmap is not set.\n");
269 return -EINVAL;
270 }
271 if (!out_md) {
272 pr_err_once("out_md is null.\n");
273 return -EINVAL;
274 }
275 if (WARN_ON_ONCE(!map->phys_map))
276 return -EINVAL;
277 if (WARN_ON_ONCE(map->nr_map == 0) || WARN_ON_ONCE(map->desc_size == 0))
278 return -EINVAL;
279
280 e = map->phys_map + map->nr_map * map->desc_size;
281 for (p = map->phys_map; p < e; p += map->desc_size) {
282 efi_memory_desc_t *md;
283 u64 size;
284 u64 end;
285
286 /*
287 * If a driver calls this after efi_free_boot_services,
288 * ->map will be NULL, and the target may also not be mapped.
289 * So just always get our own virtual map on the CPU.
290 *
291 */
292 md = early_memremap(p, sizeof (*md));
293 if (!md) {
294 pr_err_once("early_memremap(%pa, %zu) failed.\n",
295 &p, sizeof (*md));
296 return -ENOMEM;
297 }
298
299 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
300 md->type != EFI_BOOT_SERVICES_DATA &&
301 md->type != EFI_RUNTIME_SERVICES_DATA) {
302 early_memunmap(md, sizeof (*md));
303 continue;
304 }
305
306 size = md->num_pages << EFI_PAGE_SHIFT;
307 end = md->phys_addr + size;
308 if (phys_addr >= md->phys_addr && phys_addr < end) {
309 memcpy(out_md, md, sizeof(*out_md));
310 early_memunmap(md, sizeof (*md));
311 return 0;
312 }
313
314 early_memunmap(md, sizeof (*md));
315 }
316 pr_err_once("requested map not found.\n");
317 return -ENOENT;
318}
319
320/*
321 * Calculate the highest address of an efi memory descriptor.
322 */
323u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
324{
325 u64 size = md->num_pages << EFI_PAGE_SHIFT;
326 u64 end = md->phys_addr + size;
327 return end;
328}
329
330static __initdata efi_config_table_type_t common_tables[] = {
331 {ACPI_20_TABLE_GUID, "ACPI 2.0", &efi.acpi20},
332 {ACPI_TABLE_GUID, "ACPI", &efi.acpi},
333 {HCDP_TABLE_GUID, "HCDP", &efi.hcdp},
334 {MPS_TABLE_GUID, "MPS", &efi.mps},
335 {SAL_SYSTEM_TABLE_GUID, "SALsystab", &efi.sal_systab},
336 {SMBIOS_TABLE_GUID, "SMBIOS", &efi.smbios},
337 {SMBIOS3_TABLE_GUID, "SMBIOS 3.0", &efi.smbios3},
338 {UGA_IO_PROTOCOL_GUID, "UGA", &efi.uga},
339 {EFI_SYSTEM_RESOURCE_TABLE_GUID, "ESRT", &efi.esrt},
340 {EFI_PROPERTIES_TABLE_GUID, "PROP", &efi.properties_table},
341 {NULL_GUID, NULL, NULL},
342};
343
344static __init int match_config_table(efi_guid_t *guid,
345 unsigned long table,
346 efi_config_table_type_t *table_types)
347{
348 int i;
349
350 if (table_types) {
351 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
352 if (!efi_guidcmp(*guid, table_types[i].guid)) {
353 *(table_types[i].ptr) = table;
354 pr_cont(" %s=0x%lx ",
355 table_types[i].name, table);
356 return 1;
357 }
358 }
359 }
360
361 return 0;
362}
363
364int __init efi_config_parse_tables(void *config_tables, int count, int sz,
365 efi_config_table_type_t *arch_tables)
366{
367 void *tablep;
368 int i;
369
370 tablep = config_tables;
371 pr_info("");
372 for (i = 0; i < count; i++) {
373 efi_guid_t guid;
374 unsigned long table;
375
376 if (efi_enabled(EFI_64BIT)) {
377 u64 table64;
378 guid = ((efi_config_table_64_t *)tablep)->guid;
379 table64 = ((efi_config_table_64_t *)tablep)->table;
380 table = table64;
381#ifndef CONFIG_64BIT
382 if (table64 >> 32) {
383 pr_cont("\n");
384 pr_err("Table located above 4GB, disabling EFI.\n");
385 return -EINVAL;
386 }
387#endif
388 } else {
389 guid = ((efi_config_table_32_t *)tablep)->guid;
390 table = ((efi_config_table_32_t *)tablep)->table;
391 }
392
393 if (!match_config_table(&guid, table, common_tables))
394 match_config_table(&guid, table, arch_tables);
395
396 tablep += sz;
397 }
398 pr_cont("\n");
399 set_bit(EFI_CONFIG_TABLES, &efi.flags);
400
401 /* Parse the EFI Properties table if it exists */
402 if (efi.properties_table != EFI_INVALID_TABLE_ADDR) {
403 efi_properties_table_t *tbl;
404
405 tbl = early_memremap(efi.properties_table, sizeof(*tbl));
406 if (tbl == NULL) {
407 pr_err("Could not map Properties table!\n");
408 return -ENOMEM;
409 }
410
411 if (tbl->memory_protection_attribute &
412 EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA)
413 set_bit(EFI_NX_PE_DATA, &efi.flags);
414
415 early_memunmap(tbl, sizeof(*tbl));
416 }
417
418 return 0;
419}
420
421int __init efi_config_init(efi_config_table_type_t *arch_tables)
422{
423 void *config_tables;
424 int sz, ret;
425
426 if (efi_enabled(EFI_64BIT))
427 sz = sizeof(efi_config_table_64_t);
428 else
429 sz = sizeof(efi_config_table_32_t);
430
431 /*
432 * Let's see what config tables the firmware passed to us.
433 */
434 config_tables = early_memremap(efi.systab->tables,
435 efi.systab->nr_tables * sz);
436 if (config_tables == NULL) {
437 pr_err("Could not map Configuration table!\n");
438 return -ENOMEM;
439 }
440
441 ret = efi_config_parse_tables(config_tables, efi.systab->nr_tables, sz,
442 arch_tables);
443
444 early_memunmap(config_tables, efi.systab->nr_tables * sz);
445 return ret;
446}
447
448#ifdef CONFIG_EFI_VARS_MODULE
449static int __init efi_load_efivars(void)
450{
451 struct platform_device *pdev;
452
453 if (!efi_enabled(EFI_RUNTIME_SERVICES))
454 return 0;
455
456 pdev = platform_device_register_simple("efivars", 0, NULL, 0);
457 return IS_ERR(pdev) ? PTR_ERR(pdev) : 0;
458}
459device_initcall(efi_load_efivars);
460#endif
461
462#ifdef CONFIG_EFI_PARAMS_FROM_FDT
463
464#define UEFI_PARAM(name, prop, field) \
465 { \
466 { name }, \
467 { prop }, \
468 offsetof(struct efi_fdt_params, field), \
469 FIELD_SIZEOF(struct efi_fdt_params, field) \
470 }
471
472static __initdata struct {
473 const char name[32];
474 const char propname[32];
475 int offset;
476 int size;
477} dt_params[] = {
478 UEFI_PARAM("System Table", "linux,uefi-system-table", system_table),
479 UEFI_PARAM("MemMap Address", "linux,uefi-mmap-start", mmap),
480 UEFI_PARAM("MemMap Size", "linux,uefi-mmap-size", mmap_size),
481 UEFI_PARAM("MemMap Desc. Size", "linux,uefi-mmap-desc-size", desc_size),
482 UEFI_PARAM("MemMap Desc. Version", "linux,uefi-mmap-desc-ver", desc_ver)
483};
484
485struct param_info {
486 int found;
487 void *params;
488};
489
490static int __init fdt_find_uefi_params(unsigned long node, const char *uname,
491 int depth, void *data)
492{
493 struct param_info *info = data;
494 const void *prop;
495 void *dest;
496 u64 val;
497 int i, len;
498
499 if (depth != 1 || strcmp(uname, "chosen") != 0)
500 return 0;
501
502 for (i = 0; i < ARRAY_SIZE(dt_params); i++) {
503 prop = of_get_flat_dt_prop(node, dt_params[i].propname, &len);
504 if (!prop)
505 return 0;
506 dest = info->params + dt_params[i].offset;
507 info->found++;
508
509 val = of_read_number(prop, len / sizeof(u32));
510
511 if (dt_params[i].size == sizeof(u32))
512 *(u32 *)dest = val;
513 else
514 *(u64 *)dest = val;
515
516 if (efi_enabled(EFI_DBG))
517 pr_info(" %s: 0x%0*llx\n", dt_params[i].name,
518 dt_params[i].size * 2, val);
519 }
520 return 1;
521}
522
523int __init efi_get_fdt_params(struct efi_fdt_params *params)
524{
525 struct param_info info;
526 int ret;
527
528 pr_info("Getting EFI parameters from FDT:\n");
529
530 info.found = 0;
531 info.params = params;
532
533 ret = of_scan_flat_dt(fdt_find_uefi_params, &info);
534 if (!info.found)
535 pr_info("UEFI not found.\n");
536 else if (!ret)
537 pr_err("Can't find '%s' in device tree!\n",
538 dt_params[info.found].name);
539
540 return ret;
541}
542#endif /* CONFIG_EFI_PARAMS_FROM_FDT */
543
544static __initdata char memory_type_name[][20] = {
545 "Reserved",
546 "Loader Code",
547 "Loader Data",
548 "Boot Code",
549 "Boot Data",
550 "Runtime Code",
551 "Runtime Data",
552 "Conventional Memory",
553 "Unusable Memory",
554 "ACPI Reclaim Memory",
555 "ACPI Memory NVS",
556 "Memory Mapped I/O",
557 "MMIO Port Space",
558 "PAL Code",
559 "Persistent Memory",
560};
561
562char * __init efi_md_typeattr_format(char *buf, size_t size,
563 const efi_memory_desc_t *md)
564{
565 char *pos;
566 int type_len;
567 u64 attr;
568
569 pos = buf;
570 if (md->type >= ARRAY_SIZE(memory_type_name))
571 type_len = snprintf(pos, size, "[type=%u", md->type);
572 else
573 type_len = snprintf(pos, size, "[%-*s",
574 (int)(sizeof(memory_type_name[0]) - 1),
575 memory_type_name[md->type]);
576 if (type_len >= size)
577 return buf;
578
579 pos += type_len;
580 size -= type_len;
581
582 attr = md->attribute;
583 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
584 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
585 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
586 EFI_MEMORY_NV |
587 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE))
588 snprintf(pos, size, "|attr=0x%016llx]",
589 (unsigned long long)attr);
590 else
591 snprintf(pos, size,
592 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
593 attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
594 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "",
595 attr & EFI_MEMORY_NV ? "NV" : "",
596 attr & EFI_MEMORY_XP ? "XP" : "",
597 attr & EFI_MEMORY_RP ? "RP" : "",
598 attr & EFI_MEMORY_WP ? "WP" : "",
599 attr & EFI_MEMORY_RO ? "RO" : "",
600 attr & EFI_MEMORY_UCE ? "UCE" : "",
601 attr & EFI_MEMORY_WB ? "WB" : "",
602 attr & EFI_MEMORY_WT ? "WT" : "",
603 attr & EFI_MEMORY_WC ? "WC" : "",
604 attr & EFI_MEMORY_UC ? "UC" : "");
605 return buf;
606}
607
608/*
609 * efi_mem_attributes - lookup memmap attributes for physical address
610 * @phys_addr: the physical address to lookup
611 *
612 * Search in the EFI memory map for the region covering
613 * @phys_addr. Returns the EFI memory attributes if the region
614 * was found in the memory map, 0 otherwise.
615 *
616 * Despite being marked __weak, most architectures should *not*
617 * override this function. It is __weak solely for the benefit
618 * of ia64 which has a funky EFI memory map that doesn't work
619 * the same way as other architectures.
620 */
621u64 __weak efi_mem_attributes(unsigned long phys_addr)
622{
623 struct efi_memory_map *map;
624 efi_memory_desc_t *md;
625 void *p;
626
627 if (!efi_enabled(EFI_MEMMAP))
628 return 0;
629
630 map = efi.memmap;
631 for (p = map->map; p < map->map_end; p += map->desc_size) {
632 md = p;
633 if ((md->phys_addr <= phys_addr) &&
634 (phys_addr < (md->phys_addr +
635 (md->num_pages << EFI_PAGE_SHIFT))))
636 return md->attribute;
637 }
638 return 0;
639}