1 #ifndef _ASM_X86_EFI_H
2 #define _ASM_X86_EFI_H
3
4 #include <asm/fpu/api.h>
5 #include <asm/pgtable.h>
6 #include <asm/processor-flags.h>
7 #include <asm/tlb.h>
8 #include <asm/nospec-branch.h>
9
10 /*
11 * We map the EFI regions needed for runtime services non-contiguously,
12 * with preserved alignment on virtual addresses starting from -4G down
13 * for a total max space of 64G. This way, we provide for stable runtime
14 * services addresses across kernels so that a kexec'd kernel can still
15 * use them.
16 *
17 * This is the main reason why we're doing stable VA mappings for RT
18 * services.
19 *
20 * This flag is used in conjuction with a chicken bit called
21 * "efi=old_map" which can be used as a fallback to the old runtime
22 * services mapping method in case there's some b0rkage with a
23 * particular EFI implementation (haha, it is hard to hold up the
24 * sarcasm here...).
25 */
26 #define EFI_OLD_MEMMAP EFI_ARCH_1
27
28 #define EFI32_LOADER_SIGNATURE "EL32"
29 #define EFI64_LOADER_SIGNATURE "EL64"
30
31 #define MAX_CMDLINE_ADDRESS UINT_MAX
32
33 #define ARCH_EFI_IRQ_FLAGS_MASK X86_EFLAGS_IF
34
35 #ifdef CONFIG_X86_32
36
37 extern unsigned long asmlinkage efi_call_phys(void *, ...);
38
39 #define arch_efi_call_virt_setup() \
40 ({ \
41 kernel_fpu_begin(); \
42 firmware_restrict_branch_speculation_start(); \
43 })
44
45 #define arch_efi_call_virt_teardown() \
46 ({ \
47 firmware_restrict_branch_speculation_end(); \
48 kernel_fpu_end(); \
49 })
50
51
52 /*
53 * Wrap all the virtual calls in a way that forces the parameters on the stack.
54 */
55 #define arch_efi_call_virt(p, f, args...) \
56 ({ \
57 ((efi_##f##_t __attribute__((regparm(0)))*) p->f)(args); \
58 })
59
60 #define efi_ioremap(addr, size, type, attr) ioremap_cache(addr, size)
61
62 #else /* !CONFIG_X86_32 */
63
64 #define EFI_LOADER_SIGNATURE "EL64"
65
66 extern u64 asmlinkage efi_call(void *fp, ...);
67
68 #define efi_call_phys(f, args...) efi_call((f), args)
69
70 /*
71 * Scratch space used for switching the pagetable in the EFI stub
72 */
73 struct efi_scratch {
74 u64 r15;
75 u64 prev_cr3;
76 pgd_t *efi_pgt;
77 bool use_pgd;
78 u64 phys_stack;
79 } __packed;
80
81 #define arch_efi_call_virt_setup() \
82 ({ \
83 efi_sync_low_kernel_mappings(); \
84 preempt_disable(); \
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 preempt_enable(); \
108 })
109
110 extern void __iomem *__init efi_ioremap(unsigned long addr, unsigned long size,
111 u32 type, u64 attribute);
112
113 #ifdef CONFIG_KASAN
114 /*
115 * CONFIG_KASAN may redefine memset to __memset. __memset function is present
116 * only in kernel binary. Since the EFI stub linked into a separate binary it
117 * doesn't have __memset(). So we should use standard memset from
118 * arch/x86/boot/compressed/string.c. The same applies to memcpy and memmove.
119 */
120 #undef memcpy
121 #undef memset
122 #undef memmove
123 #endif
124
125 #endif /* CONFIG_X86_32 */
126
127 extern struct efi_scratch efi_scratch;
128 extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable);
129 extern int __init efi_memblock_x86_reserve_range(void);
130 extern pgd_t * __init efi_call_phys_prolog(void);
131 extern void __init efi_call_phys_epilog(pgd_t *save_pgd);
132 extern void __init efi_print_memmap(void);
133 extern void __init efi_memory_uc(u64 addr, unsigned long size);
134 extern void __init efi_map_region(efi_memory_desc_t *md);
135 extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
136 extern void efi_sync_low_kernel_mappings(void);
137 extern int __init efi_alloc_page_tables(void);
138 extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
139 extern void __init old_map_region(efi_memory_desc_t *md);
140 extern void __init runtime_code_page_mkexec(void);
141 extern void __init efi_runtime_update_mappings(void);
142 extern void __init efi_dump_pagetable(void);
143 extern void __init efi_apply_memmap_quirks(void);
144 extern int __init efi_reuse_config(u64 tables, int nr_tables);
145 extern void efi_delete_dummy_variable(void);
146
147 struct efi_setup_data {
148 u64 fw_vendor;
149 u64 runtime;
150 u64 tables;
151 u64 smbios;
152 u64 reserved[8];
153 };
154
155 extern u64 efi_setup;
156
157 #ifdef CONFIG_EFI
158
efi_is_native(void)159 static inline bool efi_is_native(void)
160 {
161 return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
162 }
163
efi_runtime_supported(void)164 static inline bool efi_runtime_supported(void)
165 {
166 if (efi_is_native())
167 return true;
168
169 if (IS_ENABLED(CONFIG_EFI_MIXED) && !efi_enabled(EFI_OLD_MEMMAP))
170 return true;
171
172 return false;
173 }
174
175 extern struct console early_efi_console;
176 extern void parse_efi_setup(u64 phys_addr, u32 data_len);
177
178 extern void efifb_setup_from_dmi(struct screen_info *si, const char *opt);
179
180 #ifdef CONFIG_EFI_MIXED
181 extern void efi_thunk_runtime_setup(void);
182 extern efi_status_t efi_thunk_set_virtual_address_map(
183 void *phys_set_virtual_address_map,
184 unsigned long memory_map_size,
185 unsigned long descriptor_size,
186 u32 descriptor_version,
187 efi_memory_desc_t *virtual_map);
188 #else
efi_thunk_runtime_setup(void)189 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)190 static inline efi_status_t efi_thunk_set_virtual_address_map(
191 void *phys_set_virtual_address_map,
192 unsigned long memory_map_size,
193 unsigned long descriptor_size,
194 u32 descriptor_version,
195 efi_memory_desc_t *virtual_map)
196 {
197 return EFI_SUCCESS;
198 }
199 #endif /* CONFIG_EFI_MIXED */
200
201
202 /* arch specific definitions used by the stub code */
203
204 struct efi_config {
205 u64 image_handle;
206 u64 table;
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_call_early(f, ...) \
227 __efi_early()->call(efi_is_64bit() ? \
228 ((efi_boot_services_64_t *)(unsigned long) \
229 __efi_early()->boot_services)->f : \
230 ((efi_boot_services_32_t *)(unsigned long) \
231 __efi_early()->boot_services)->f, __VA_ARGS__)
232
233 #define __efi_call_early(f, ...) \
234 __efi_early()->call((unsigned long)f, __VA_ARGS__);
235
236 extern bool efi_reboot_required(void);
237
238 #else
parse_efi_setup(u64 phys_addr,u32 data_len)239 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
efi_reboot_required(void)240 static inline bool efi_reboot_required(void)
241 {
242 return false;
243 }
244 #endif /* CONFIG_EFI */
245
246 #endif /* _ASM_X86_EFI_H */
247