xref: /linux/arch/x86/include/asm/efi.h (revision 3b812ecce736432e6b55e77028ea387eb1517d24)
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 #define MAX_CMDLINE_ADDRESS	UINT_MAX
29 
30 #ifdef CONFIG_X86_32
31 
32 
33 extern unsigned long asmlinkage efi_call_phys(void *, ...);
34 
35 /*
36  * Wrap all the virtual calls in a way that forces the parameters on the stack.
37  */
38 
39 /* Use this macro if your virtual returns a non-void value */
40 #define efi_call_virt(f, args...) \
41 ({									\
42 	efi_status_t __s;						\
43 	kernel_fpu_begin();						\
44 	__s = ((efi_##f##_t __attribute__((regparm(0)))*)		\
45 		efi.systab->runtime->f)(args);				\
46 	kernel_fpu_end();						\
47 	__s;								\
48 })
49 
50 /* Use this macro if your virtual call does not return any value */
51 #define __efi_call_virt(f, args...) \
52 ({									\
53 	kernel_fpu_begin();						\
54 	((efi_##f##_t __attribute__((regparm(0)))*)			\
55 		efi.systab->runtime->f)(args);				\
56 	kernel_fpu_end();						\
57 })
58 
59 #define efi_ioremap(addr, size, type, attr)	ioremap_cache(addr, size)
60 
61 #else /* !CONFIG_X86_32 */
62 
63 #define EFI_LOADER_SIGNATURE	"EL64"
64 
65 extern u64 asmlinkage efi_call(void *fp, ...);
66 
67 #define efi_call_phys(f, args...)		efi_call((f), args)
68 
69 #define efi_call_virt(f, ...)						\
70 ({									\
71 	efi_status_t __s;						\
72 									\
73 	efi_sync_low_kernel_mappings();					\
74 	preempt_disable();						\
75 	__kernel_fpu_begin();						\
76 	__s = efi_call((void *)efi.systab->runtime->f, __VA_ARGS__);	\
77 	__kernel_fpu_end();						\
78 	preempt_enable();						\
79 	__s;								\
80 })
81 
82 /*
83  * All X86_64 virt calls return non-void values. Thus, use non-void call for
84  * virt calls that would be void on X86_32.
85  */
86 #define __efi_call_virt(f, args...) efi_call_virt(f, args)
87 
88 extern void __iomem *__init efi_ioremap(unsigned long addr, unsigned long size,
89 					u32 type, u64 attribute);
90 
91 #ifdef CONFIG_KASAN
92 /*
93  * CONFIG_KASAN may redefine memset to __memset.  __memset function is present
94  * only in kernel binary.  Since the EFI stub linked into a separate binary it
95  * doesn't have __memset().  So we should use standard memset from
96  * arch/x86/boot/compressed/string.c.  The same applies to memcpy and memmove.
97  */
98 #undef memcpy
99 #undef memset
100 #undef memmove
101 #endif
102 
103 #endif /* CONFIG_X86_32 */
104 
105 extern struct efi_scratch efi_scratch;
106 extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable);
107 extern int __init efi_memblock_x86_reserve_range(void);
108 extern pgd_t * __init efi_call_phys_prolog(void);
109 extern void __init efi_call_phys_epilog(pgd_t *save_pgd);
110 extern void __init efi_print_memmap(void);
111 extern void __init efi_unmap_memmap(void);
112 extern void __init efi_memory_uc(u64 addr, unsigned long size);
113 extern void __init efi_map_region(efi_memory_desc_t *md);
114 extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
115 extern void efi_sync_low_kernel_mappings(void);
116 extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
117 extern void __init efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages);
118 extern void __init old_map_region(efi_memory_desc_t *md);
119 extern void __init runtime_code_page_mkexec(void);
120 extern void __init efi_runtime_mkexec(void);
121 extern void __init efi_dump_pagetable(void);
122 extern void __init efi_apply_memmap_quirks(void);
123 extern int __init efi_reuse_config(u64 tables, int nr_tables);
124 extern void efi_delete_dummy_variable(void);
125 
126 struct efi_setup_data {
127 	u64 fw_vendor;
128 	u64 runtime;
129 	u64 tables;
130 	u64 smbios;
131 	u64 reserved[8];
132 };
133 
134 extern u64 efi_setup;
135 
136 #ifdef CONFIG_EFI
137 
138 static inline bool efi_is_native(void)
139 {
140 	return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
141 }
142 
143 static inline bool efi_runtime_supported(void)
144 {
145 	if (efi_is_native())
146 		return true;
147 
148 	if (IS_ENABLED(CONFIG_EFI_MIXED) && !efi_enabled(EFI_OLD_MEMMAP))
149 		return true;
150 
151 	return false;
152 }
153 
154 extern struct console early_efi_console;
155 extern void parse_efi_setup(u64 phys_addr, u32 data_len);
156 
157 #ifdef CONFIG_EFI_MIXED
158 extern void efi_thunk_runtime_setup(void);
159 extern efi_status_t efi_thunk_set_virtual_address_map(
160 	void *phys_set_virtual_address_map,
161 	unsigned long memory_map_size,
162 	unsigned long descriptor_size,
163 	u32 descriptor_version,
164 	efi_memory_desc_t *virtual_map);
165 #else
166 static inline void efi_thunk_runtime_setup(void) {}
167 static inline efi_status_t efi_thunk_set_virtual_address_map(
168 	void *phys_set_virtual_address_map,
169 	unsigned long memory_map_size,
170 	unsigned long descriptor_size,
171 	u32 descriptor_version,
172 	efi_memory_desc_t *virtual_map)
173 {
174 	return EFI_SUCCESS;
175 }
176 #endif /* CONFIG_EFI_MIXED */
177 
178 
179 /* arch specific definitions used by the stub code */
180 
181 struct efi_config {
182 	u64 image_handle;
183 	u64 table;
184 	u64 allocate_pool;
185 	u64 allocate_pages;
186 	u64 get_memory_map;
187 	u64 free_pool;
188 	u64 free_pages;
189 	u64 locate_handle;
190 	u64 handle_protocol;
191 	u64 exit_boot_services;
192 	u64 text_output;
193 	efi_status_t (*call)(unsigned long, ...);
194 	bool is64;
195 } __packed;
196 
197 __pure const struct efi_config *__efi_early(void);
198 
199 #define efi_call_early(f, ...)						\
200 	__efi_early()->call(__efi_early()->f, __VA_ARGS__);
201 
202 extern bool efi_reboot_required(void);
203 
204 #else
205 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
206 static inline bool efi_reboot_required(void)
207 {
208 	return false;
209 }
210 #endif /* CONFIG_EFI */
211 
212 #endif /* _ASM_X86_EFI_H */
213