Commit | Line | Data |
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f84d0275 MS |
1 | /* |
2 | * Extensible Firmware Interface | |
3 | * | |
4 | * Based on Extensible Firmware Interface Specification version 2.4 | |
5 | * | |
6 | * Copyright (C) 2013, 2014 Linaro Ltd. | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License version 2 as | |
10 | * published by the Free Software Foundation. | |
11 | * | |
12 | */ | |
13 | ||
f3cdfd23 | 14 | #include <linux/atomic.h> |
d1ae8c00 | 15 | #include <linux/dmi.h> |
f84d0275 MS |
16 | #include <linux/efi.h> |
17 | #include <linux/export.h> | |
18 | #include <linux/memblock.h> | |
f3cdfd23 | 19 | #include <linux/mm_types.h> |
f84d0275 MS |
20 | #include <linux/bootmem.h> |
21 | #include <linux/of.h> | |
22 | #include <linux/of_fdt.h> | |
f3cdfd23 AB |
23 | #include <linux/preempt.h> |
24 | #include <linux/rbtree.h> | |
25 | #include <linux/rwsem.h> | |
f84d0275 MS |
26 | #include <linux/sched.h> |
27 | #include <linux/slab.h> | |
f3cdfd23 | 28 | #include <linux/spinlock.h> |
f84d0275 MS |
29 | |
30 | #include <asm/cacheflush.h> | |
31 | #include <asm/efi.h> | |
32 | #include <asm/tlbflush.h> | |
33 | #include <asm/mmu_context.h> | |
f3cdfd23 AB |
34 | #include <asm/mmu.h> |
35 | #include <asm/pgtable.h> | |
f84d0275 MS |
36 | |
37 | struct efi_memory_map memmap; | |
38 | ||
f84d0275 MS |
39 | static u64 efi_system_table; |
40 | ||
60305db9 AB |
41 | static pgd_t efi_pgd[PTRS_PER_PGD] __page_aligned_bss; |
42 | ||
43 | static struct mm_struct efi_mm = { | |
44 | .mm_rb = RB_ROOT, | |
45 | .pgd = efi_pgd, | |
46 | .mm_users = ATOMIC_INIT(2), | |
47 | .mm_count = ATOMIC_INIT(1), | |
48 | .mmap_sem = __RWSEM_INITIALIZER(efi_mm.mmap_sem), | |
49 | .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock), | |
50 | .mmlist = LIST_HEAD_INIT(efi_mm.mmlist), | |
51 | INIT_MM_CONTEXT(efi_mm) | |
52 | }; | |
53 | ||
f84d0275 MS |
54 | static int uefi_debug __initdata; |
55 | static int __init uefi_debug_setup(char *str) | |
56 | { | |
57 | uefi_debug = 1; | |
58 | ||
59 | return 0; | |
60 | } | |
61 | early_param("uefi_debug", uefi_debug_setup); | |
62 | ||
63 | static int __init is_normal_ram(efi_memory_desc_t *md) | |
64 | { | |
65 | if (md->attribute & EFI_MEMORY_WB) | |
66 | return 1; | |
67 | return 0; | |
68 | } | |
69 | ||
f3cdfd23 AB |
70 | /* |
71 | * Translate a EFI virtual address into a physical address: this is necessary, | |
72 | * as some data members of the EFI system table are virtually remapped after | |
73 | * SetVirtualAddressMap() has been called. | |
74 | */ | |
75 | static phys_addr_t efi_to_phys(unsigned long addr) | |
76 | { | |
77 | efi_memory_desc_t *md; | |
78 | ||
79 | for_each_efi_memory_desc(&memmap, md) { | |
80 | if (!(md->attribute & EFI_MEMORY_RUNTIME)) | |
81 | continue; | |
82 | if (md->virt_addr == 0) | |
83 | /* no virtual mapping has been installed by the stub */ | |
84 | break; | |
85 | if (md->virt_addr <= addr && | |
86 | (addr - md->virt_addr) < (md->num_pages << EFI_PAGE_SHIFT)) | |
87 | return md->phys_addr + addr - md->virt_addr; | |
88 | } | |
89 | return addr; | |
90 | } | |
91 | ||
f84d0275 MS |
92 | static int __init uefi_init(void) |
93 | { | |
94 | efi_char16_t *c16; | |
f3cdfd23 AB |
95 | void *config_tables; |
96 | u64 table_size; | |
f84d0275 MS |
97 | char vendor[100] = "unknown"; |
98 | int i, retval; | |
99 | ||
100 | efi.systab = early_memremap(efi_system_table, | |
101 | sizeof(efi_system_table_t)); | |
102 | if (efi.systab == NULL) { | |
103 | pr_warn("Unable to map EFI system table.\n"); | |
104 | return -ENOMEM; | |
105 | } | |
106 | ||
107 | set_bit(EFI_BOOT, &efi.flags); | |
108 | set_bit(EFI_64BIT, &efi.flags); | |
109 | ||
110 | /* | |
111 | * Verify the EFI Table | |
112 | */ | |
113 | if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) { | |
114 | pr_err("System table signature incorrect\n"); | |
88f8abd5 DY |
115 | retval = -EINVAL; |
116 | goto out; | |
f84d0275 MS |
117 | } |
118 | if ((efi.systab->hdr.revision >> 16) < 2) | |
119 | pr_warn("Warning: EFI system table version %d.%02d, expected 2.00 or greater\n", | |
120 | efi.systab->hdr.revision >> 16, | |
121 | efi.systab->hdr.revision & 0xffff); | |
122 | ||
123 | /* Show what we know for posterity */ | |
f3cdfd23 | 124 | c16 = early_memremap(efi_to_phys(efi.systab->fw_vendor), |
f91b1fea | 125 | sizeof(vendor) * sizeof(efi_char16_t)); |
f84d0275 MS |
126 | if (c16) { |
127 | for (i = 0; i < (int) sizeof(vendor) - 1 && *c16; ++i) | |
128 | vendor[i] = c16[i]; | |
129 | vendor[i] = '\0'; | |
f91b1fea | 130 | early_memunmap(c16, sizeof(vendor) * sizeof(efi_char16_t)); |
f84d0275 MS |
131 | } |
132 | ||
133 | pr_info("EFI v%u.%.02u by %s\n", | |
134 | efi.systab->hdr.revision >> 16, | |
135 | efi.systab->hdr.revision & 0xffff, vendor); | |
136 | ||
f3cdfd23 AB |
137 | table_size = sizeof(efi_config_table_64_t) * efi.systab->nr_tables; |
138 | config_tables = early_memremap(efi_to_phys(efi.systab->tables), | |
139 | table_size); | |
140 | ||
141 | retval = efi_config_parse_tables(config_tables, efi.systab->nr_tables, | |
142 | sizeof(efi_config_table_64_t), NULL); | |
f84d0275 | 143 | |
f3cdfd23 | 144 | early_memunmap(config_tables, table_size); |
88f8abd5 | 145 | out: |
f84d0275 | 146 | early_memunmap(efi.systab, sizeof(efi_system_table_t)); |
f84d0275 MS |
147 | return retval; |
148 | } | |
149 | ||
f84d0275 MS |
150 | /* |
151 | * Return true for RAM regions we want to permanently reserve. | |
152 | */ | |
153 | static __init int is_reserve_region(efi_memory_desc_t *md) | |
154 | { | |
61139eb0 AB |
155 | switch (md->type) { |
156 | case EFI_LOADER_CODE: | |
157 | case EFI_LOADER_DATA: | |
158 | case EFI_BOOT_SERVICES_CODE: | |
159 | case EFI_BOOT_SERVICES_DATA: | |
160 | case EFI_CONVENTIONAL_MEMORY: | |
ad5fb870 | 161 | case EFI_PERSISTENT_MEMORY: |
f84d0275 | 162 | return 0; |
61139eb0 AB |
163 | default: |
164 | break; | |
165 | } | |
166 | return is_normal_ram(md); | |
f84d0275 MS |
167 | } |
168 | ||
169 | static __init void reserve_regions(void) | |
170 | { | |
171 | efi_memory_desc_t *md; | |
172 | u64 paddr, npages, size; | |
173 | ||
174 | if (uefi_debug) | |
175 | pr_info("Processing EFI memory map:\n"); | |
176 | ||
177 | for_each_efi_memory_desc(&memmap, md) { | |
178 | paddr = md->phys_addr; | |
179 | npages = md->num_pages; | |
180 | ||
65ba758f LE |
181 | if (uefi_debug) { |
182 | char buf[64]; | |
183 | ||
184 | pr_info(" 0x%012llx-0x%012llx %s", | |
f84d0275 | 185 | paddr, paddr + (npages << EFI_PAGE_SHIFT) - 1, |
65ba758f LE |
186 | efi_md_typeattr_format(buf, sizeof(buf), md)); |
187 | } | |
f84d0275 MS |
188 | |
189 | memrange_efi_to_native(&paddr, &npages); | |
190 | size = npages << PAGE_SHIFT; | |
191 | ||
192 | if (is_normal_ram(md)) | |
193 | early_init_dt_add_memory_arch(paddr, size); | |
194 | ||
3033b845 | 195 | if (is_reserve_region(md)) { |
f84d0275 MS |
196 | memblock_reserve(paddr, size); |
197 | if (uefi_debug) | |
198 | pr_cont("*"); | |
199 | } | |
200 | ||
201 | if (uefi_debug) | |
202 | pr_cont("\n"); | |
203 | } | |
86c8b27a LL |
204 | |
205 | set_bit(EFI_MEMMAP, &efi.flags); | |
f84d0275 MS |
206 | } |
207 | ||
f84d0275 MS |
208 | void __init efi_init(void) |
209 | { | |
210 | struct efi_fdt_params params; | |
211 | ||
212 | /* Grab UEFI information placed in FDT by stub */ | |
213 | if (!efi_get_fdt_params(¶ms, uefi_debug)) | |
214 | return; | |
215 | ||
216 | efi_system_table = params.system_table; | |
217 | ||
218 | memblock_reserve(params.mmap & PAGE_MASK, | |
219 | PAGE_ALIGN(params.mmap_size + (params.mmap & ~PAGE_MASK))); | |
220 | memmap.phys_map = (void *)params.mmap; | |
221 | memmap.map = early_memremap(params.mmap, params.mmap_size); | |
222 | memmap.map_end = memmap.map + params.mmap_size; | |
223 | memmap.desc_size = params.desc_size; | |
224 | memmap.desc_version = params.desc_ver; | |
225 | ||
226 | if (uefi_init() < 0) | |
227 | return; | |
228 | ||
229 | reserve_regions(); | |
60305db9 AB |
230 | early_memunmap(memmap.map, params.mmap_size); |
231 | } | |
232 | ||
233 | static bool __init efi_virtmap_init(void) | |
234 | { | |
235 | efi_memory_desc_t *md; | |
236 | ||
237 | for_each_efi_memory_desc(&memmap, md) { | |
238 | u64 paddr, npages, size; | |
239 | pgprot_t prot; | |
240 | ||
241 | if (!(md->attribute & EFI_MEMORY_RUNTIME)) | |
242 | continue; | |
243 | if (md->virt_addr == 0) | |
244 | return false; | |
245 | ||
246 | paddr = md->phys_addr; | |
247 | npages = md->num_pages; | |
248 | memrange_efi_to_native(&paddr, &npages); | |
249 | size = npages << PAGE_SHIFT; | |
250 | ||
251 | pr_info(" EFI remap 0x%016llx => %p\n", | |
252 | md->phys_addr, (void *)md->virt_addr); | |
253 | ||
254 | /* | |
255 | * Only regions of type EFI_RUNTIME_SERVICES_CODE need to be | |
256 | * executable, everything else can be mapped with the XN bits | |
257 | * set. | |
258 | */ | |
259 | if (!is_normal_ram(md)) | |
260 | prot = __pgprot(PROT_DEVICE_nGnRE); | |
261 | else if (md->type == EFI_RUNTIME_SERVICES_CODE) | |
262 | prot = PAGE_KERNEL_EXEC; | |
263 | else | |
264 | prot = PAGE_KERNEL; | |
265 | ||
266 | create_pgd_mapping(&efi_mm, paddr, md->virt_addr, size, prot); | |
267 | } | |
268 | return true; | |
f84d0275 MS |
269 | } |
270 | ||
f84d0275 | 271 | /* |
f3cdfd23 AB |
272 | * Enable the UEFI Runtime Services if all prerequisites are in place, i.e., |
273 | * non-early mapping of the UEFI system table and virtual mappings for all | |
274 | * EFI_MEMORY_RUNTIME regions. | |
f84d0275 | 275 | */ |
f3cdfd23 | 276 | static int __init arm64_enable_runtime_services(void) |
f84d0275 | 277 | { |
f84d0275 | 278 | u64 mapsize; |
f84d0275 MS |
279 | |
280 | if (!efi_enabled(EFI_BOOT)) { | |
281 | pr_info("EFI services will not be available.\n"); | |
282 | return -1; | |
283 | } | |
284 | ||
6632210f DY |
285 | if (efi_runtime_disabled()) { |
286 | pr_info("EFI runtime services will be disabled.\n"); | |
287 | return -1; | |
288 | } | |
289 | ||
290 | pr_info("Remapping and enabling EFI services.\n"); | |
7fe5d2b1 AB |
291 | |
292 | mapsize = memmap.map_end - memmap.map; | |
f84d0275 MS |
293 | memmap.map = (__force void *)ioremap_cache((phys_addr_t)memmap.phys_map, |
294 | mapsize); | |
7fe5d2b1 AB |
295 | if (!memmap.map) { |
296 | pr_err("Failed to remap EFI memory map\n"); | |
297 | return -1; | |
298 | } | |
f84d0275 | 299 | memmap.map_end = memmap.map + mapsize; |
f84d0275 MS |
300 | efi.memmap = &memmap; |
301 | ||
f3cdfd23 AB |
302 | efi.systab = (__force void *)ioremap_cache(efi_system_table, |
303 | sizeof(efi_system_table_t)); | |
99a5603e | 304 | if (!efi.systab) { |
f3cdfd23 AB |
305 | pr_err("Failed to remap EFI System Table\n"); |
306 | return -1; | |
99a5603e AB |
307 | } |
308 | set_bit(EFI_SYSTEM_TABLES, &efi.flags); | |
f84d0275 | 309 | |
60305db9 | 310 | if (!efi_virtmap_init()) { |
f3cdfd23 | 311 | pr_err("No UEFI virtual mapping was installed -- runtime services will not be available\n"); |
f84d0275 MS |
312 | return -1; |
313 | } | |
314 | ||
315 | /* Set up runtime services function pointers */ | |
e15dd494 | 316 | efi_native_runtime_setup(); |
f84d0275 MS |
317 | set_bit(EFI_RUNTIME_SERVICES, &efi.flags); |
318 | ||
6a7519e8 SP |
319 | efi.runtime_version = efi.systab->hdr.revision; |
320 | ||
f84d0275 MS |
321 | return 0; |
322 | } | |
f3cdfd23 | 323 | early_initcall(arm64_enable_runtime_services); |
d1ae8c00 YL |
324 | |
325 | static int __init arm64_dmi_init(void) | |
326 | { | |
327 | /* | |
328 | * On arm64, DMI depends on UEFI, and dmi_scan_machine() needs to | |
329 | * be called early because dmi_id_init(), which is an arch_initcall | |
330 | * itself, depends on dmi_scan_machine() having been called already. | |
331 | */ | |
332 | dmi_scan_machine(); | |
b07bfaa3 AB |
333 | if (dmi_available) |
334 | dmi_set_dump_stack_arch_desc(); | |
d1ae8c00 YL |
335 | return 0; |
336 | } | |
337 | core_initcall(arm64_dmi_init); | |
f3cdfd23 | 338 | |
f3cdfd23 AB |
339 | static void efi_set_pgd(struct mm_struct *mm) |
340 | { | |
130c93fd WD |
341 | if (mm == &init_mm) |
342 | cpu_set_reserved_ttbr0(); | |
343 | else | |
344 | cpu_switch_mm(mm->pgd, mm); | |
345 | ||
f3cdfd23 AB |
346 | flush_tlb_all(); |
347 | if (icache_is_aivivt()) | |
348 | __flush_icache_all(); | |
349 | } | |
350 | ||
351 | void efi_virtmap_load(void) | |
352 | { | |
353 | preempt_disable(); | |
354 | efi_set_pgd(&efi_mm); | |
355 | } | |
356 | ||
357 | void efi_virtmap_unload(void) | |
358 | { | |
359 | efi_set_pgd(current->active_mm); | |
360 | preempt_enable(); | |
361 | } | |
60c0d45a AB |
362 | |
363 | /* | |
364 | * UpdateCapsule() depends on the system being shutdown via | |
365 | * ResetSystem(). | |
366 | */ | |
367 | bool efi_poweroff_required(void) | |
368 | { | |
369 | return efi_enabled(EFI_RUNTIME_SERVICES); | |
370 | } |