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14#include <linux/atomic.h>
15#include <linux/dmi.h>
16#include <linux/efi.h>
17#include <linux/export.h>
18#include <linux/memblock.h>
19#include <linux/mm_types.h>
20#include <linux/bootmem.h>
21#include <linux/of.h>
22#include <linux/of_fdt.h>
23#include <linux/preempt.h>
24#include <linux/rbtree.h>
25#include <linux/rwsem.h>
26#include <linux/sched.h>
27#include <linux/slab.h>
28#include <linux/spinlock.h>
29
30#include <asm/cacheflush.h>
31#include <asm/efi.h>
32#include <asm/tlbflush.h>
33#include <asm/mmu_context.h>
34#include <asm/mmu.h>
35#include <asm/pgtable.h>
36
37struct efi_memory_map memmap;
38
39static u64 efi_system_table;
40
41static pgd_t efi_pgd[PTRS_PER_PGD] __page_aligned_bss;
42
43static 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};
52
53static int __init is_normal_ram(efi_memory_desc_t *md)
54{
55 if (md->attribute & EFI_MEMORY_WB)
56 return 1;
57 return 0;
58}
59
60
61
62
63
64
65static phys_addr_t efi_to_phys(unsigned long addr)
66{
67 efi_memory_desc_t *md;
68
69 for_each_efi_memory_desc(&memmap, md) {
70 if (!(md->attribute & EFI_MEMORY_RUNTIME))
71 continue;
72 if (md->virt_addr == 0)
73
74 break;
75 if (md->virt_addr <= addr &&
76 (addr - md->virt_addr) < (md->num_pages << EFI_PAGE_SHIFT))
77 return md->phys_addr + addr - md->virt_addr;
78 }
79 return addr;
80}
81
82static int __init uefi_init(void)
83{
84 efi_char16_t *c16;
85 void *config_tables;
86 u64 table_size;
87 char vendor[100] = "unknown";
88 int i, retval;
89
90 efi.systab = early_memremap(efi_system_table,
91 sizeof(efi_system_table_t));
92 if (efi.systab == NULL) {
93 pr_warn("Unable to map EFI system table.\n");
94 return -ENOMEM;
95 }
96
97 set_bit(EFI_BOOT, &efi.flags);
98 set_bit(EFI_64BIT, &efi.flags);
99
100
101
102
103 if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
104 pr_err("System table signature incorrect\n");
105 retval = -EINVAL;
106 goto out;
107 }
108 if ((efi.systab->hdr.revision >> 16) < 2)
109 pr_warn("Warning: EFI system table version %d.%02d, expected 2.00 or greater\n",
110 efi.systab->hdr.revision >> 16,
111 efi.systab->hdr.revision & 0xffff);
112
113
114 c16 = early_memremap(efi_to_phys(efi.systab->fw_vendor),
115 sizeof(vendor) * sizeof(efi_char16_t));
116 if (c16) {
117 for (i = 0; i < (int) sizeof(vendor) - 1 && *c16; ++i)
118 vendor[i] = c16[i];
119 vendor[i] = '\0';
120 early_memunmap(c16, sizeof(vendor) * sizeof(efi_char16_t));
121 }
122
123 pr_info("EFI v%u.%.02u by %s\n",
124 efi.systab->hdr.revision >> 16,
125 efi.systab->hdr.revision & 0xffff, vendor);
126
127 table_size = sizeof(efi_config_table_64_t) * efi.systab->nr_tables;
128 config_tables = early_memremap(efi_to_phys(efi.systab->tables),
129 table_size);
130 if (config_tables == NULL) {
131 pr_warn("Unable to map EFI config table array.\n");
132 retval = -ENOMEM;
133 goto out;
134 }
135 retval = efi_config_parse_tables(config_tables, efi.systab->nr_tables,
136 sizeof(efi_config_table_64_t), NULL);
137
138 early_memunmap(config_tables, table_size);
139out:
140 early_memunmap(efi.systab, sizeof(efi_system_table_t));
141 return retval;
142}
143
144
145
146
147static __init int is_reserve_region(efi_memory_desc_t *md)
148{
149 switch (md->type) {
150 case EFI_LOADER_CODE:
151 case EFI_LOADER_DATA:
152 case EFI_BOOT_SERVICES_CODE:
153 case EFI_BOOT_SERVICES_DATA:
154 case EFI_CONVENTIONAL_MEMORY:
155 case EFI_PERSISTENT_MEMORY:
156 return 0;
157 default:
158 break;
159 }
160 return is_normal_ram(md);
161}
162
163static __init void reserve_regions(void)
164{
165 efi_memory_desc_t *md;
166 u64 paddr, npages, size;
167
168 if (efi_enabled(EFI_DBG))
169 pr_info("Processing EFI memory map:\n");
170
171 for_each_efi_memory_desc(&memmap, md) {
172 paddr = md->phys_addr;
173 npages = md->num_pages;
174
175 if (efi_enabled(EFI_DBG)) {
176 char buf[64];
177
178 pr_info(" 0x%012llx-0x%012llx %s",
179 paddr, paddr + (npages << EFI_PAGE_SHIFT) - 1,
180 efi_md_typeattr_format(buf, sizeof(buf), md));
181 }
182
183 memrange_efi_to_native(&paddr, &npages);
184 size = npages << PAGE_SHIFT;
185
186 if (is_normal_ram(md))
187 early_init_dt_add_memory_arch(paddr, size);
188
189 if (is_reserve_region(md)) {
190 memblock_reserve(paddr, size);
191 if (efi_enabled(EFI_DBG))
192 pr_cont("*");
193 }
194
195 if (efi_enabled(EFI_DBG))
196 pr_cont("\n");
197 }
198
199 set_bit(EFI_MEMMAP, &efi.flags);
200}
201
202void __init efi_init(void)
203{
204 struct efi_fdt_params params;
205
206
207 if (!efi_get_fdt_params(¶ms))
208 return;
209
210 efi_system_table = params.system_table;
211
212 memblock_reserve(params.mmap & PAGE_MASK,
213 PAGE_ALIGN(params.mmap_size + (params.mmap & ~PAGE_MASK)));
214 memmap.phys_map = params.mmap;
215 memmap.map = early_memremap(params.mmap, params.mmap_size);
216 if (memmap.map == NULL) {
217
218
219
220
221
222 panic("Unable to map EFI memory map.\n");
223 }
224 memmap.map_end = memmap.map + params.mmap_size;
225 memmap.desc_size = params.desc_size;
226 memmap.desc_version = params.desc_ver;
227
228 if (uefi_init() < 0)
229 return;
230
231 reserve_regions();
232 early_memunmap(memmap.map, params.mmap_size);
233}
234
235static bool __init efi_virtmap_init(void)
236{
237 efi_memory_desc_t *md;
238
239 init_new_context(NULL, &efi_mm);
240
241 for_each_efi_memory_desc(&memmap, md) {
242 pgprot_t prot;
243
244 if (!(md->attribute & EFI_MEMORY_RUNTIME))
245 continue;
246 if (md->virt_addr == 0)
247 return false;
248
249 pr_info(" EFI remap 0x%016llx => %p\n",
250 md->phys_addr, (void *)md->virt_addr);
251
252
253
254
255
256
257 if (!is_normal_ram(md))
258 prot = __pgprot(PROT_DEVICE_nGnRE);
259 else if (md->type == EFI_RUNTIME_SERVICES_CODE ||
260 !PAGE_ALIGNED(md->phys_addr))
261 prot = PAGE_KERNEL_EXEC;
262 else
263 prot = PAGE_KERNEL;
264
265 create_pgd_mapping(&efi_mm, md->phys_addr, md->virt_addr,
266 md->num_pages << EFI_PAGE_SHIFT,
267 __pgprot(pgprot_val(prot) | PTE_NG));
268 }
269 return true;
270}
271
272
273
274
275
276
277static int __init arm64_enable_runtime_services(void)
278{
279 u64 mapsize;
280
281 if (!efi_enabled(EFI_BOOT)) {
282 pr_info("EFI services will not be available.\n");
283 return 0;
284 }
285
286 if (efi_runtime_disabled()) {
287 pr_info("EFI runtime services will be disabled.\n");
288 return 0;
289 }
290
291 pr_info("Remapping and enabling EFI services.\n");
292
293 mapsize = memmap.map_end - memmap.map;
294 memmap.map = (__force void *)ioremap_cache(memmap.phys_map,
295 mapsize);
296 if (!memmap.map) {
297 pr_err("Failed to remap EFI memory map\n");
298 return -ENOMEM;
299 }
300 memmap.map_end = memmap.map + mapsize;
301 efi.memmap = &memmap;
302
303 efi.systab = (__force void *)ioremap_cache(efi_system_table,
304 sizeof(efi_system_table_t));
305 if (!efi.systab) {
306 pr_err("Failed to remap EFI System Table\n");
307 return -ENOMEM;
308 }
309 set_bit(EFI_SYSTEM_TABLES, &efi.flags);
310
311 if (!efi_virtmap_init()) {
312 pr_err("No UEFI virtual mapping was installed -- runtime services will not be available\n");
313 return -ENOMEM;
314 }
315
316
317 efi_native_runtime_setup();
318 set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
319
320 efi.runtime_version = efi.systab->hdr.revision;
321
322 return 0;
323}
324early_initcall(arm64_enable_runtime_services);
325
326static int __init arm64_dmi_init(void)
327{
328
329
330
331
332
333 dmi_scan_machine();
334 if (dmi_available)
335 dmi_set_dump_stack_arch_desc();
336 return 0;
337}
338core_initcall(arm64_dmi_init);
339
340static void efi_set_pgd(struct mm_struct *mm)
341{
342 switch_mm(NULL, mm, NULL);
343}
344
345void efi_virtmap_load(void)
346{
347 preempt_disable();
348 efi_set_pgd(&efi_mm);
349}
350
351void efi_virtmap_unload(void)
352{
353 efi_set_pgd(current->active_mm);
354 preempt_enable();
355}
356
357
358
359
360
361bool efi_poweroff_required(void)
362{
363 return efi_enabled(EFI_RUNTIME_SERVICES);
364}
365
