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Linux kernel mirror (for testing)
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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
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
37extern asmlinkage unsigned long efi_call_phys(void *, ...);
38
39#define arch_efi_call_virt_setup() kernel_fpu_begin()
40#define arch_efi_call_virt_teardown() kernel_fpu_end()
41
42/*
43 * Wrap all the virtual calls in a way that forces the parameters on the stack.
44 */
45#define arch_efi_call_virt(p, f, args...) \
46({ \
47 ((efi_##f##_t __attribute__((regparm(0)))*) p->f)(args); \
48})
49
50#define efi_ioremap(addr, size, type, attr) ioremap_cache(addr, size)
51
52#else /* !CONFIG_X86_32 */
53
54#define EFI_LOADER_SIGNATURE "EL64"
55
56extern asmlinkage u64 efi_call(void *fp, ...);
57
58#define efi_call_phys(f, args...) efi_call((f), args)
59
60/*
61 * Scratch space used for switching the pagetable in the EFI stub
62 */
63struct efi_scratch {
64 u64 r15;
65 u64 prev_cr3;
66 pgd_t *efi_pgt;
67 bool use_pgd;
68 u64 phys_stack;
69} __packed;
70
71#define arch_efi_call_virt_setup() \
72({ \
73 efi_sync_low_kernel_mappings(); \
74 preempt_disable(); \
75 __kernel_fpu_begin(); \
76 \
77 if (efi_scratch.use_pgd) { \
78 efi_scratch.prev_cr3 = __read_cr3(); \
79 write_cr3((unsigned long)efi_scratch.efi_pgt); \
80 __flush_tlb_all(); \
81 } \
82})
83
84#define arch_efi_call_virt(p, f, args...) \
85 efi_call((void *)p->f, args) \
86
87#define arch_efi_call_virt_teardown() \
88({ \
89 if (efi_scratch.use_pgd) { \
90 write_cr3(efi_scratch.prev_cr3); \
91 __flush_tlb_all(); \
92 } \
93 \
94 __kernel_fpu_end(); \
95 preempt_enable(); \
96})
97
98extern void __iomem *__init efi_ioremap(unsigned long addr, unsigned long size,
99 u32 type, u64 attribute);
100
101#ifdef CONFIG_KASAN
102/*
103 * CONFIG_KASAN may redefine memset to __memset. __memset function is present
104 * only in kernel binary. Since the EFI stub linked into a separate binary it
105 * doesn't have __memset(). So we should use standard memset from
106 * arch/x86/boot/compressed/string.c. The same applies to memcpy and memmove.
107 */
108#undef memcpy
109#undef memset
110#undef memmove
111#endif
112
113#endif /* CONFIG_X86_32 */
114
115extern struct efi_scratch efi_scratch;
116extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable);
117extern int __init efi_memblock_x86_reserve_range(void);
118extern pgd_t * __init efi_call_phys_prolog(void);
119extern void __init efi_call_phys_epilog(pgd_t *save_pgd);
120extern void __init efi_print_memmap(void);
121extern void __init efi_memory_uc(u64 addr, unsigned long size);
122extern void __init efi_map_region(efi_memory_desc_t *md);
123extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
124extern void efi_sync_low_kernel_mappings(void);
125extern int __init efi_alloc_page_tables(void);
126extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
127extern void __init old_map_region(efi_memory_desc_t *md);
128extern void __init runtime_code_page_mkexec(void);
129extern void __init efi_runtime_update_mappings(void);
130extern void __init efi_dump_pagetable(void);
131extern void __init efi_apply_memmap_quirks(void);
132extern int __init efi_reuse_config(u64 tables, int nr_tables);
133extern void efi_delete_dummy_variable(void);
134
135struct efi_setup_data {
136 u64 fw_vendor;
137 u64 runtime;
138 u64 tables;
139 u64 smbios;
140 u64 reserved[8];
141};
142
143extern u64 efi_setup;
144
145#ifdef CONFIG_EFI
146
147static inline bool efi_is_native(void)
148{
149 return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
150}
151
152static inline bool efi_runtime_supported(void)
153{
154 if (efi_is_native())
155 return true;
156
157 if (IS_ENABLED(CONFIG_EFI_MIXED) && !efi_enabled(EFI_OLD_MEMMAP))
158 return true;
159
160 return false;
161}
162
163extern struct console early_efi_console;
164extern void parse_efi_setup(u64 phys_addr, u32 data_len);
165
166extern void efifb_setup_from_dmi(struct screen_info *si, const char *opt);
167
168#ifdef CONFIG_EFI_MIXED
169extern void efi_thunk_runtime_setup(void);
170extern efi_status_t efi_thunk_set_virtual_address_map(
171 void *phys_set_virtual_address_map,
172 unsigned long memory_map_size,
173 unsigned long descriptor_size,
174 u32 descriptor_version,
175 efi_memory_desc_t *virtual_map);
176#else
177static inline void efi_thunk_runtime_setup(void) {}
178static inline efi_status_t efi_thunk_set_virtual_address_map(
179 void *phys_set_virtual_address_map,
180 unsigned long memory_map_size,
181 unsigned long descriptor_size,
182 u32 descriptor_version,
183 efi_memory_desc_t *virtual_map)
184{
185 return EFI_SUCCESS;
186}
187#endif /* CONFIG_EFI_MIXED */
188
189
190/* arch specific definitions used by the stub code */
191
192struct efi_config {
193 u64 image_handle;
194 u64 table;
195 u64 runtime_services;
196 u64 boot_services;
197 u64 text_output;
198 efi_status_t (*call)(unsigned long, ...);
199 bool is64;
200} __packed;
201
202__pure const struct efi_config *__efi_early(void);
203
204static inline bool efi_is_64bit(void)
205{
206 if (!IS_ENABLED(CONFIG_X86_64))
207 return false;
208
209 if (!IS_ENABLED(CONFIG_EFI_MIXED))
210 return true;
211
212 return __efi_early()->is64;
213}
214
215#define efi_table_attr(table, attr, instance) \
216 (efi_is_64bit() ? \
217 ((table##_64_t *)(unsigned long)instance)->attr : \
218 ((table##_32_t *)(unsigned long)instance)->attr)
219
220#define efi_call_proto(protocol, f, instance, ...) \
221 __efi_early()->call(efi_table_attr(protocol, f, instance), \
222 instance, ##__VA_ARGS__)
223
224#define efi_call_early(f, ...) \
225 __efi_early()->call(efi_table_attr(efi_boot_services, f, \
226 __efi_early()->boot_services), __VA_ARGS__)
227
228#define __efi_call_early(f, ...) \
229 __efi_early()->call((unsigned long)f, __VA_ARGS__);
230
231#define efi_call_runtime(f, ...) \
232 __efi_early()->call(efi_table_attr(efi_runtime_services, f, \
233 __efi_early()->runtime_services), __VA_ARGS__)
234
235extern bool efi_reboot_required(void);
236
237#else
238static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
239static inline bool efi_reboot_required(void)
240{
241 return false;
242}
243#endif /* CONFIG_EFI */
244
245#endif /* _ASM_X86_EFI_H */