xref: /openbmc/linux/arch/x86/include/asm/efi.h (revision eb3fcf007fffe5830d815e713591f3e858f2a365)
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 /*
90  * CONFIG_KASAN may redefine memset to __memset.  __memset function is present
91  * only in kernel binary.  Since the EFI stub linked into a separate binary it
92  * doesn't have __memset().  So we should use standard memset from
93  * arch/x86/boot/compressed/string.c.  The same applies to memcpy and memmove.
94  */
95 #undef memcpy
96 #undef memset
97 #undef memmove
98 
99 #endif /* CONFIG_X86_32 */
100 
101 extern struct efi_scratch efi_scratch;
102 extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable);
103 extern int __init efi_memblock_x86_reserve_range(void);
104 extern pgd_t * __init efi_call_phys_prolog(void);
105 extern void __init efi_call_phys_epilog(pgd_t *save_pgd);
106 extern void __init efi_unmap_memmap(void);
107 extern void __init efi_memory_uc(u64 addr, unsigned long size);
108 extern void __init efi_map_region(efi_memory_desc_t *md);
109 extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
110 extern void efi_sync_low_kernel_mappings(void);
111 extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
112 extern void __init efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages);
113 extern void __init old_map_region(efi_memory_desc_t *md);
114 extern void __init runtime_code_page_mkexec(void);
115 extern void __init efi_runtime_mkexec(void);
116 extern void __init efi_dump_pagetable(void);
117 extern void __init efi_apply_memmap_quirks(void);
118 extern int __init efi_reuse_config(u64 tables, int nr_tables);
119 extern void efi_delete_dummy_variable(void);
120 
121 struct efi_setup_data {
122 	u64 fw_vendor;
123 	u64 runtime;
124 	u64 tables;
125 	u64 smbios;
126 	u64 reserved[8];
127 };
128 
129 extern u64 efi_setup;
130 
131 #ifdef CONFIG_EFI
132 
133 static inline bool efi_is_native(void)
134 {
135 	return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
136 }
137 
138 static inline bool efi_runtime_supported(void)
139 {
140 	if (efi_is_native())
141 		return true;
142 
143 	if (IS_ENABLED(CONFIG_EFI_MIXED) && !efi_enabled(EFI_OLD_MEMMAP))
144 		return true;
145 
146 	return false;
147 }
148 
149 extern struct console early_efi_console;
150 extern void parse_efi_setup(u64 phys_addr, u32 data_len);
151 
152 #ifdef CONFIG_EFI_MIXED
153 extern void efi_thunk_runtime_setup(void);
154 extern efi_status_t efi_thunk_set_virtual_address_map(
155 	void *phys_set_virtual_address_map,
156 	unsigned long memory_map_size,
157 	unsigned long descriptor_size,
158 	u32 descriptor_version,
159 	efi_memory_desc_t *virtual_map);
160 #else
161 static inline void efi_thunk_runtime_setup(void) {}
162 static inline efi_status_t efi_thunk_set_virtual_address_map(
163 	void *phys_set_virtual_address_map,
164 	unsigned long memory_map_size,
165 	unsigned long descriptor_size,
166 	u32 descriptor_version,
167 	efi_memory_desc_t *virtual_map)
168 {
169 	return EFI_SUCCESS;
170 }
171 #endif /* CONFIG_EFI_MIXED */
172 
173 
174 /* arch specific definitions used by the stub code */
175 
176 struct efi_config {
177 	u64 image_handle;
178 	u64 table;
179 	u64 allocate_pool;
180 	u64 allocate_pages;
181 	u64 get_memory_map;
182 	u64 free_pool;
183 	u64 free_pages;
184 	u64 locate_handle;
185 	u64 handle_protocol;
186 	u64 exit_boot_services;
187 	u64 text_output;
188 	efi_status_t (*call)(unsigned long, ...);
189 	bool is64;
190 } __packed;
191 
192 __pure const struct efi_config *__efi_early(void);
193 
194 #define efi_call_early(f, ...)						\
195 	__efi_early()->call(__efi_early()->f, __VA_ARGS__);
196 
197 extern bool efi_reboot_required(void);
198 
199 #else
200 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
201 static inline bool efi_reboot_required(void)
202 {
203 	return false;
204 }
205 #endif /* CONFIG_EFI */
206 
207 #endif /* _ASM_X86_EFI_H */
208