1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_EFI_H
3 #define _ASM_X86_EFI_H
4
5 #include <asm/fpu/api.h>
6 #include <asm/pgtable.h>
7 #include <asm/processor-flags.h>
8 #include <asm/tlb.h>
9 #include <asm/nospec-branch.h>
10
11 /*
12 * We map the EFI regions needed for runtime services non-contiguously,
13 * with preserved alignment on virtual addresses starting from -4G down
14 * for a total max space of 64G. This way, we provide for stable runtime
15 * services addresses across kernels so that a kexec'd kernel can still
16 * use them.
17 *
18 * This is the main reason why we're doing stable VA mappings for RT
19 * services.
20 *
21 * This flag is used in conjuction with a chicken bit called
22 * "efi=old_map" which can be used as a fallback to the old runtime
23 * services mapping method in case there's some b0rkage with a
24 * particular EFI implementation (haha, it is hard to hold up the
25 * sarcasm here...).
26 */
27 #define EFI_OLD_MEMMAP EFI_ARCH_1
28
29 #define EFI32_LOADER_SIGNATURE "EL32"
30 #define EFI64_LOADER_SIGNATURE "EL64"
31
32 #define MAX_CMDLINE_ADDRESS UINT_MAX
33
34 #define ARCH_EFI_IRQ_FLAGS_MASK X86_EFLAGS_IF
35
36 #ifdef CONFIG_X86_32
37
38 extern asmlinkage unsigned long efi_call_phys(void *, ...);
39
40 #define arch_efi_call_virt_setup() \
41 ({ \
42 kernel_fpu_begin(); \
43 firmware_restrict_branch_speculation_start(); \
44 })
45
46 #define arch_efi_call_virt_teardown() \
47 ({ \
48 firmware_restrict_branch_speculation_end(); \
49 kernel_fpu_end(); \
50 })
51
52
53 /*
54 * Wrap all the virtual calls in a way that forces the parameters on the stack.
55 */
56 #define arch_efi_call_virt(p, f, args...) \
57 ({ \
58 ((efi_##f##_t __attribute__((regparm(0)))*) p->f)(args); \
59 })
60
61 #define efi_ioremap(addr, size, type, attr) ioremap_cache(addr, size)
62
63 #else /* !CONFIG_X86_32 */
64
65 #define EFI_LOADER_SIGNATURE "EL64"
66
67 extern asmlinkage u64 efi_call(void *fp, ...);
68
69 #define efi_call_phys(f, args...) efi_call((f), args)
70
71 /*
72 * Scratch space used for switching the pagetable in the EFI stub
73 */
74 struct efi_scratch {
75 u64 r15;
76 u64 prev_cr3;
77 pgd_t *efi_pgt;
78 bool use_pgd;
79 u64 phys_stack;
80 } __packed;
81
82 #define arch_efi_call_virt_setup() \
83 ({ \
84 efi_sync_low_kernel_mappings(); \
85 kernel_fpu_begin(); \
86 firmware_restrict_branch_speculation_start(); \
87 \
88 if (efi_scratch.use_pgd) { \
89 efi_scratch.prev_cr3 = __read_cr3(); \
90 write_cr3((unsigned long)efi_scratch.efi_pgt); \
91 __flush_tlb_all(); \
92 } \
93 })
94
95 #define arch_efi_call_virt(p, f, args...) \
96 efi_call((void *)p->f, args) \
97
98 #define arch_efi_call_virt_teardown() \
99 ({ \
100 if (efi_scratch.use_pgd) { \
101 write_cr3(efi_scratch.prev_cr3); \
102 __flush_tlb_all(); \
103 } \
104 \
105 firmware_restrict_branch_speculation_end(); \
106 kernel_fpu_end(); \
107 })
108
109 extern void __iomem *__init efi_ioremap(unsigned long addr, unsigned long size,
110 u32 type, u64 attribute);
111
112 #ifdef CONFIG_KASAN
113 /*
114 * CONFIG_KASAN may redefine memset to __memset. __memset function is present
115 * only in kernel binary. Since the EFI stub linked into a separate binary it
116 * doesn't have __memset(). So we should use standard memset from
117 * arch/x86/boot/compressed/string.c. The same applies to memcpy and memmove.
118 */
119 #undef memcpy
120 #undef memset
121 #undef memmove
122 #endif
123
124 #endif /* CONFIG_X86_32 */
125
126 extern struct efi_scratch efi_scratch;
127 extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable);
128 extern int __init efi_memblock_x86_reserve_range(void);
129 extern pgd_t * __init efi_call_phys_prolog(void);
130 extern void __init efi_call_phys_epilog(pgd_t *save_pgd);
131 extern void __init efi_print_memmap(void);
132 extern void __init efi_memory_uc(u64 addr, unsigned long size);
133 extern void __init efi_map_region(efi_memory_desc_t *md);
134 extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
135 extern void efi_sync_low_kernel_mappings(void);
136 extern int __init efi_alloc_page_tables(void);
137 extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
138 extern void __init old_map_region(efi_memory_desc_t *md);
139 extern void __init runtime_code_page_mkexec(void);
140 extern void __init efi_runtime_update_mappings(void);
141 extern void __init efi_dump_pagetable(void);
142 extern void __init efi_apply_memmap_quirks(void);
143 extern int __init efi_reuse_config(u64 tables, int nr_tables);
144 extern void efi_delete_dummy_variable(void);
145
146 struct efi_setup_data {
147 u64 fw_vendor;
148 u64 runtime;
149 u64 tables;
150 u64 smbios;
151 u64 reserved[8];
152 };
153
154 extern u64 efi_setup;
155
156 #ifdef CONFIG_EFI
157
efi_is_native(void)158 static inline bool efi_is_native(void)
159 {
160 return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
161 }
162
efi_runtime_supported(void)163 static inline bool efi_runtime_supported(void)
164 {
165 if (efi_is_native())
166 return true;
167
168 if (IS_ENABLED(CONFIG_EFI_MIXED) && !efi_enabled(EFI_OLD_MEMMAP))
169 return true;
170
171 return false;
172 }
173
174 extern struct console early_efi_console;
175 extern void parse_efi_setup(u64 phys_addr, u32 data_len);
176
177 extern void efifb_setup_from_dmi(struct screen_info *si, const char *opt);
178
179 #ifdef CONFIG_EFI_MIXED
180 extern void efi_thunk_runtime_setup(void);
181 extern efi_status_t efi_thunk_set_virtual_address_map(
182 void *phys_set_virtual_address_map,
183 unsigned long memory_map_size,
184 unsigned long descriptor_size,
185 u32 descriptor_version,
186 efi_memory_desc_t *virtual_map);
187 #else
efi_thunk_runtime_setup(void)188 static inline void efi_thunk_runtime_setup(void) {}
efi_thunk_set_virtual_address_map(void * phys_set_virtual_address_map,unsigned long memory_map_size,unsigned long descriptor_size,u32 descriptor_version,efi_memory_desc_t * virtual_map)189 static inline efi_status_t efi_thunk_set_virtual_address_map(
190 void *phys_set_virtual_address_map,
191 unsigned long memory_map_size,
192 unsigned long descriptor_size,
193 u32 descriptor_version,
194 efi_memory_desc_t *virtual_map)
195 {
196 return EFI_SUCCESS;
197 }
198 #endif /* CONFIG_EFI_MIXED */
199
200
201 /* arch specific definitions used by the stub code */
202
203 struct efi_config {
204 u64 image_handle;
205 u64 table;
206 u64 runtime_services;
207 u64 boot_services;
208 u64 text_output;
209 efi_status_t (*call)(unsigned long, ...);
210 bool is64;
211 } __packed;
212
213 __pure const struct efi_config *__efi_early(void);
214
efi_is_64bit(void)215 static inline bool efi_is_64bit(void)
216 {
217 if (!IS_ENABLED(CONFIG_X86_64))
218 return false;
219
220 if (!IS_ENABLED(CONFIG_EFI_MIXED))
221 return true;
222
223 return __efi_early()->is64;
224 }
225
226 #define efi_table_attr(table, attr, instance) \
227 (efi_is_64bit() ? \
228 ((table##_64_t *)(unsigned long)instance)->attr : \
229 ((table##_32_t *)(unsigned long)instance)->attr)
230
231 #define efi_call_proto(protocol, f, instance, ...) \
232 __efi_early()->call(efi_table_attr(protocol, f, instance), \
233 instance, ##__VA_ARGS__)
234
235 #define efi_call_early(f, ...) \
236 __efi_early()->call(efi_table_attr(efi_boot_services, f, \
237 __efi_early()->boot_services), __VA_ARGS__)
238
239 #define __efi_call_early(f, ...) \
240 __efi_early()->call((unsigned long)f, __VA_ARGS__);
241
242 #define efi_call_runtime(f, ...) \
243 __efi_early()->call(efi_table_attr(efi_runtime_services, f, \
244 __efi_early()->runtime_services), __VA_ARGS__)
245
246 extern bool efi_reboot_required(void);
247
248 #else
parse_efi_setup(u64 phys_addr,u32 data_len)249 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
efi_reboot_required(void)250 static inline bool efi_reboot_required(void)
251 {
252 return false;
253 }
254 #endif /* CONFIG_EFI */
255
256 #endif /* _ASM_X86_EFI_H */
257