xref: /linux/arch/x86/include/asm/efi.h (revision b85d45947951d23cb22d90caecf4c1eb81342c96)
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 
7 /*
8  * We map the EFI regions needed for runtime services non-contiguously,
9  * with preserved alignment on virtual addresses starting from -4G down
10  * for a total max space of 64G. This way, we provide for stable runtime
11  * services addresses across kernels so that a kexec'd kernel can still
12  * use them.
13  *
14  * This is the main reason why we're doing stable VA mappings for RT
15  * services.
16  *
17  * This flag is used in conjuction with a chicken bit called
18  * "efi=old_map" which can be used as a fallback to the old runtime
19  * services mapping method in case there's some b0rkage with a
20  * particular EFI implementation (haha, it is hard to hold up the
21  * sarcasm here...).
22  */
23 #define EFI_OLD_MEMMAP		EFI_ARCH_1
24 
25 #define EFI32_LOADER_SIGNATURE	"EL32"
26 #define EFI64_LOADER_SIGNATURE	"EL64"
27 
28 #ifdef CONFIG_X86_32
29 
30 
31 extern unsigned long asmlinkage efi_call_phys(void *, ...);
32 
33 /*
34  * Wrap all the virtual calls in a way that forces the parameters on the stack.
35  */
36 
37 /* Use this macro if your virtual returns a non-void value */
38 #define efi_call_virt(f, args...) \
39 ({									\
40 	efi_status_t __s;						\
41 	kernel_fpu_begin();						\
42 	__s = ((efi_##f##_t __attribute__((regparm(0)))*)		\
43 		efi.systab->runtime->f)(args);				\
44 	kernel_fpu_end();						\
45 	__s;								\
46 })
47 
48 /* Use this macro if your virtual call does not return any value */
49 #define __efi_call_virt(f, args...) \
50 ({									\
51 	kernel_fpu_begin();						\
52 	((efi_##f##_t __attribute__((regparm(0)))*)			\
53 		efi.systab->runtime->f)(args);				\
54 	kernel_fpu_end();						\
55 })
56 
57 #define efi_ioremap(addr, size, type, attr)	ioremap_cache(addr, size)
58 
59 #else /* !CONFIG_X86_32 */
60 
61 #define EFI_LOADER_SIGNATURE	"EL64"
62 
63 extern u64 asmlinkage efi_call(void *fp, ...);
64 
65 #define efi_call_phys(f, args...)		efi_call((f), args)
66 
67 #define efi_call_virt(f, ...)						\
68 ({									\
69 	efi_status_t __s;						\
70 									\
71 	efi_sync_low_kernel_mappings();					\
72 	preempt_disable();						\
73 	__kernel_fpu_begin();						\
74 	__s = efi_call((void *)efi.systab->runtime->f, __VA_ARGS__);	\
75 	__kernel_fpu_end();						\
76 	preempt_enable();						\
77 	__s;								\
78 })
79 
80 /*
81  * All X86_64 virt calls return non-void values. Thus, use non-void call for
82  * virt calls that would be void on X86_32.
83  */
84 #define __efi_call_virt(f, args...) efi_call_virt(f, args)
85 
86 extern void __iomem *__init efi_ioremap(unsigned long addr, unsigned long size,
87 					u32 type, u64 attribute);
88 
89 #ifdef CONFIG_KASAN
90 /*
91  * CONFIG_KASAN may redefine memset to __memset.  __memset function is present
92  * only in kernel binary.  Since the EFI stub linked into a separate binary it
93  * doesn't have __memset().  So we should use standard memset from
94  * arch/x86/boot/compressed/string.c.  The same applies to memcpy and memmove.
95  */
96 #undef memcpy
97 #undef memset
98 #undef memmove
99 #endif
100 
101 #endif /* CONFIG_X86_32 */
102 
103 extern struct efi_scratch efi_scratch;
104 extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable);
105 extern int __init efi_memblock_x86_reserve_range(void);
106 extern pgd_t * __init efi_call_phys_prolog(void);
107 extern void __init efi_call_phys_epilog(pgd_t *save_pgd);
108 extern void __init efi_unmap_memmap(void);
109 extern void __init efi_memory_uc(u64 addr, unsigned long size);
110 extern void __init efi_map_region(efi_memory_desc_t *md);
111 extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
112 extern void efi_sync_low_kernel_mappings(void);
113 extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
114 extern void __init efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages);
115 extern void __init old_map_region(efi_memory_desc_t *md);
116 extern void __init runtime_code_page_mkexec(void);
117 extern void __init efi_runtime_mkexec(void);
118 extern void __init efi_dump_pagetable(void);
119 extern void __init efi_apply_memmap_quirks(void);
120 extern int __init efi_reuse_config(u64 tables, int nr_tables);
121 extern void efi_delete_dummy_variable(void);
122 
123 struct efi_setup_data {
124 	u64 fw_vendor;
125 	u64 runtime;
126 	u64 tables;
127 	u64 smbios;
128 	u64 reserved[8];
129 };
130 
131 extern u64 efi_setup;
132 
133 #ifdef CONFIG_EFI
134 
135 static inline bool efi_is_native(void)
136 {
137 	return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
138 }
139 
140 static inline bool efi_runtime_supported(void)
141 {
142 	if (efi_is_native())
143 		return true;
144 
145 	if (IS_ENABLED(CONFIG_EFI_MIXED) && !efi_enabled(EFI_OLD_MEMMAP))
146 		return true;
147 
148 	return false;
149 }
150 
151 extern struct console early_efi_console;
152 extern void parse_efi_setup(u64 phys_addr, u32 data_len);
153 
154 #ifdef CONFIG_EFI_MIXED
155 extern void efi_thunk_runtime_setup(void);
156 extern efi_status_t efi_thunk_set_virtual_address_map(
157 	void *phys_set_virtual_address_map,
158 	unsigned long memory_map_size,
159 	unsigned long descriptor_size,
160 	u32 descriptor_version,
161 	efi_memory_desc_t *virtual_map);
162 #else
163 static inline void efi_thunk_runtime_setup(void) {}
164 static inline efi_status_t efi_thunk_set_virtual_address_map(
165 	void *phys_set_virtual_address_map,
166 	unsigned long memory_map_size,
167 	unsigned long descriptor_size,
168 	u32 descriptor_version,
169 	efi_memory_desc_t *virtual_map)
170 {
171 	return EFI_SUCCESS;
172 }
173 #endif /* CONFIG_EFI_MIXED */
174 
175 
176 /* arch specific definitions used by the stub code */
177 
178 struct efi_config {
179 	u64 image_handle;
180 	u64 table;
181 	u64 allocate_pool;
182 	u64 allocate_pages;
183 	u64 get_memory_map;
184 	u64 free_pool;
185 	u64 free_pages;
186 	u64 locate_handle;
187 	u64 handle_protocol;
188 	u64 exit_boot_services;
189 	u64 text_output;
190 	efi_status_t (*call)(unsigned long, ...);
191 	bool is64;
192 } __packed;
193 
194 __pure const struct efi_config *__efi_early(void);
195 
196 #define efi_call_early(f, ...)						\
197 	__efi_early()->call(__efi_early()->f, __VA_ARGS__);
198 
199 extern bool efi_reboot_required(void);
200 
201 #else
202 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
203 static inline bool efi_reboot_required(void)
204 {
205 	return false;
206 }
207 #endif /* CONFIG_EFI */
208 
209 #endif /* _ASM_X86_EFI_H */
210