xref: /linux/arch/x86/include/asm/efi.h (revision 0883c2c06fb5bcf5b9e008270827e63c09a88c1e)
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 
9 /*
10  * We map the EFI regions needed for runtime services non-contiguously,
11  * with preserved alignment on virtual addresses starting from -4G down
12  * for a total max space of 64G. This way, we provide for stable runtime
13  * services addresses across kernels so that a kexec'd kernel can still
14  * use them.
15  *
16  * This is the main reason why we're doing stable VA mappings for RT
17  * services.
18  *
19  * This flag is used in conjuction with a chicken bit called
20  * "efi=old_map" which can be used as a fallback to the old runtime
21  * services mapping method in case there's some b0rkage with a
22  * particular EFI implementation (haha, it is hard to hold up the
23  * sarcasm here...).
24  */
25 #define EFI_OLD_MEMMAP		EFI_ARCH_1
26 
27 #define EFI32_LOADER_SIGNATURE	"EL32"
28 #define EFI64_LOADER_SIGNATURE	"EL64"
29 
30 #define MAX_CMDLINE_ADDRESS	UINT_MAX
31 
32 #define ARCH_EFI_IRQ_FLAGS_MASK	X86_EFLAGS_IF
33 
34 #ifdef CONFIG_X86_32
35 
36 extern unsigned long asmlinkage efi_call_phys(void *, ...);
37 
38 #define arch_efi_call_virt_setup()	kernel_fpu_begin()
39 #define arch_efi_call_virt_teardown()	kernel_fpu_end()
40 
41 /*
42  * Wrap all the virtual calls in a way that forces the parameters on the stack.
43  */
44 #define arch_efi_call_virt(f, args...)					\
45 ({									\
46 	((efi_##f##_t __attribute__((regparm(0)))*)			\
47 		efi.systab->runtime->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 
56 extern u64 asmlinkage 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  */
63 struct 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(f, args...)					\
85 	efi_call((void *)efi.systab->runtime->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 
98 extern 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 
115 extern struct efi_scratch efi_scratch;
116 extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable);
117 extern int __init efi_memblock_x86_reserve_range(void);
118 extern pgd_t * __init efi_call_phys_prolog(void);
119 extern void __init efi_call_phys_epilog(pgd_t *save_pgd);
120 extern void __init efi_print_memmap(void);
121 extern void __init efi_unmap_memmap(void);
122 extern void __init efi_memory_uc(u64 addr, unsigned long size);
123 extern void __init efi_map_region(efi_memory_desc_t *md);
124 extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
125 extern void efi_sync_low_kernel_mappings(void);
126 extern int __init efi_alloc_page_tables(void);
127 extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
128 extern void __init efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages);
129 extern void __init old_map_region(efi_memory_desc_t *md);
130 extern void __init runtime_code_page_mkexec(void);
131 extern void __init efi_runtime_update_mappings(void);
132 extern void __init efi_dump_pagetable(void);
133 extern void __init efi_apply_memmap_quirks(void);
134 extern int __init efi_reuse_config(u64 tables, int nr_tables);
135 extern void efi_delete_dummy_variable(void);
136 
137 struct efi_setup_data {
138 	u64 fw_vendor;
139 	u64 runtime;
140 	u64 tables;
141 	u64 smbios;
142 	u64 reserved[8];
143 };
144 
145 extern u64 efi_setup;
146 
147 #ifdef CONFIG_EFI
148 
149 static inline bool efi_is_native(void)
150 {
151 	return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
152 }
153 
154 static inline bool efi_runtime_supported(void)
155 {
156 	if (efi_is_native())
157 		return true;
158 
159 	if (IS_ENABLED(CONFIG_EFI_MIXED) && !efi_enabled(EFI_OLD_MEMMAP))
160 		return true;
161 
162 	return false;
163 }
164 
165 extern struct console early_efi_console;
166 extern void parse_efi_setup(u64 phys_addr, u32 data_len);
167 
168 extern void efifb_setup_from_dmi(struct screen_info *si, const char *opt);
169 
170 #ifdef CONFIG_EFI_MIXED
171 extern void efi_thunk_runtime_setup(void);
172 extern efi_status_t efi_thunk_set_virtual_address_map(
173 	void *phys_set_virtual_address_map,
174 	unsigned long memory_map_size,
175 	unsigned long descriptor_size,
176 	u32 descriptor_version,
177 	efi_memory_desc_t *virtual_map);
178 #else
179 static inline void efi_thunk_runtime_setup(void) {}
180 static inline efi_status_t efi_thunk_set_virtual_address_map(
181 	void *phys_set_virtual_address_map,
182 	unsigned long memory_map_size,
183 	unsigned long descriptor_size,
184 	u32 descriptor_version,
185 	efi_memory_desc_t *virtual_map)
186 {
187 	return EFI_SUCCESS;
188 }
189 #endif /* CONFIG_EFI_MIXED */
190 
191 
192 /* arch specific definitions used by the stub code */
193 
194 struct efi_config {
195 	u64 image_handle;
196 	u64 table;
197 	u64 allocate_pool;
198 	u64 allocate_pages;
199 	u64 get_memory_map;
200 	u64 free_pool;
201 	u64 free_pages;
202 	u64 locate_handle;
203 	u64 handle_protocol;
204 	u64 exit_boot_services;
205 	u64 text_output;
206 	efi_status_t (*call)(unsigned long, ...);
207 	bool is64;
208 } __packed;
209 
210 __pure const struct efi_config *__efi_early(void);
211 
212 #define efi_call_early(f, ...)						\
213 	__efi_early()->call(__efi_early()->f, __VA_ARGS__);
214 
215 #define __efi_call_early(f, ...)					\
216 	__efi_early()->call((unsigned long)f, __VA_ARGS__);
217 
218 #define efi_is_64bit()		__efi_early()->is64
219 
220 extern bool efi_reboot_required(void);
221 
222 #else
223 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
224 static inline bool efi_reboot_required(void)
225 {
226 	return false;
227 }
228 #endif /* CONFIG_EFI */
229 
230 #endif /* _ASM_X86_EFI_H */
231