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