xref: /openbmc/linux/arch/x86/include/asm/efi.h (revision d7a3d85e)
1 #ifndef _ASM_X86_EFI_H
2 #define _ASM_X86_EFI_H
3 
4 #include <asm/i387.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 #endif /* CONFIG_X86_32 */
90 
91 extern struct efi_scratch efi_scratch;
92 extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable);
93 extern int __init efi_memblock_x86_reserve_range(void);
94 extern pgd_t * __init efi_call_phys_prolog(void);
95 extern void __init efi_call_phys_epilog(pgd_t *save_pgd);
96 extern void __init efi_unmap_memmap(void);
97 extern void __init efi_memory_uc(u64 addr, unsigned long size);
98 extern void __init efi_map_region(efi_memory_desc_t *md);
99 extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
100 extern void efi_sync_low_kernel_mappings(void);
101 extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
102 extern void __init efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages);
103 extern void __init old_map_region(efi_memory_desc_t *md);
104 extern void __init runtime_code_page_mkexec(void);
105 extern void __init efi_runtime_mkexec(void);
106 extern void __init efi_dump_pagetable(void);
107 extern void __init efi_apply_memmap_quirks(void);
108 extern int __init efi_reuse_config(u64 tables, int nr_tables);
109 extern void efi_delete_dummy_variable(void);
110 
111 struct efi_setup_data {
112 	u64 fw_vendor;
113 	u64 runtime;
114 	u64 tables;
115 	u64 smbios;
116 	u64 reserved[8];
117 };
118 
119 extern u64 efi_setup;
120 
121 #ifdef CONFIG_EFI
122 
123 static inline bool efi_is_native(void)
124 {
125 	return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
126 }
127 
128 static inline bool efi_runtime_supported(void)
129 {
130 	if (efi_is_native())
131 		return true;
132 
133 	if (IS_ENABLED(CONFIG_EFI_MIXED) && !efi_enabled(EFI_OLD_MEMMAP))
134 		return true;
135 
136 	return false;
137 }
138 
139 extern struct console early_efi_console;
140 extern void parse_efi_setup(u64 phys_addr, u32 data_len);
141 
142 #ifdef CONFIG_EFI_MIXED
143 extern void efi_thunk_runtime_setup(void);
144 extern efi_status_t efi_thunk_set_virtual_address_map(
145 	void *phys_set_virtual_address_map,
146 	unsigned long memory_map_size,
147 	unsigned long descriptor_size,
148 	u32 descriptor_version,
149 	efi_memory_desc_t *virtual_map);
150 #else
151 static inline void efi_thunk_runtime_setup(void) {}
152 static inline efi_status_t efi_thunk_set_virtual_address_map(
153 	void *phys_set_virtual_address_map,
154 	unsigned long memory_map_size,
155 	unsigned long descriptor_size,
156 	u32 descriptor_version,
157 	efi_memory_desc_t *virtual_map)
158 {
159 	return EFI_SUCCESS;
160 }
161 #endif /* CONFIG_EFI_MIXED */
162 
163 
164 /* arch specific definitions used by the stub code */
165 
166 struct efi_config {
167 	u64 image_handle;
168 	u64 table;
169 	u64 allocate_pool;
170 	u64 allocate_pages;
171 	u64 get_memory_map;
172 	u64 free_pool;
173 	u64 free_pages;
174 	u64 locate_handle;
175 	u64 handle_protocol;
176 	u64 exit_boot_services;
177 	u64 text_output;
178 	efi_status_t (*call)(unsigned long, ...);
179 	bool is64;
180 } __packed;
181 
182 __pure const struct efi_config *__efi_early(void);
183 
184 #define efi_call_early(f, ...)						\
185 	__efi_early()->call(__efi_early()->f, __VA_ARGS__);
186 
187 extern bool efi_reboot_required(void);
188 
189 #else
190 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
191 static inline bool efi_reboot_required(void)
192 {
193 	return false;
194 }
195 #endif /* CONFIG_EFI */
196 
197 #endif /* _ASM_X86_EFI_H */
198