summaryrefslogtreecommitdiffstats
path: root/arch/x86/include/asm/efi.h
blob: baa549f8e9188037b4a93dc1c265d837ec15dc1f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_EFI_H
#define _ASM_X86_EFI_H

#include <asm/fpu/api.h>
#include <asm/pgtable.h>
#include <asm/processor-flags.h>
#include <asm/tlb.h>
#include <asm/nospec-branch.h>
#include <asm/mmu_context.h>

/*
 * We map the EFI regions needed for runtime services non-contiguously,
 * with preserved alignment on virtual addresses starting from -4G down
 * for a total max space of 64G. This way, we provide for stable runtime
 * services addresses across kernels so that a kexec'd kernel can still
 * use them.
 *
 * This is the main reason why we're doing stable VA mappings for RT
 * services.
 *
 * This flag is used in conjuction with a chicken bit called
 * "efi=old_map" which can be used as a fallback to the old runtime
 * services mapping method in case there's some b0rkage with a
 * particular EFI implementation (haha, it is hard to hold up the
 * sarcasm here...).
 */
#define EFI_OLD_MEMMAP		EFI_ARCH_1

#define EFI32_LOADER_SIGNATURE	"EL32"
#define EFI64_LOADER_SIGNATURE	"EL64"

#define MAX_CMDLINE_ADDRESS	UINT_MAX

#define ARCH_EFI_IRQ_FLAGS_MASK	X86_EFLAGS_IF

#ifdef CONFIG_X86_32

extern asmlinkage unsigned long efi_call_phys(void *, ...);

#define arch_efi_call_virt_setup()					\
({									\
	kernel_fpu_begin();						\
	firmware_restrict_branch_speculation_start();			\
})

#define arch_efi_call_virt_teardown()					\
({									\
	firmware_restrict_branch_speculation_end();			\
	kernel_fpu_end();						\
})


/*
 * Wrap all the virtual calls in a way that forces the parameters on the stack.
 */
#define arch_efi_call_virt(p, f, args...)				\
({									\
	((efi_##f##_t __attribute__((regparm(0)))*) p->f)(args);	\
})

#define efi_ioremap(addr, size, type, attr)	ioremap_cache(addr, size)

#else /* !CONFIG_X86_32 */

#define EFI_LOADER_SIGNATURE	"EL64"

extern asmlinkage u64 efi_call(void *fp, ...);

#define efi_call_phys(f, args...)		efi_call((f), args)

/*
 * struct efi_scratch - Scratch space used while switching to/from efi_mm
 * @phys_stack: stack used during EFI Mixed Mode
 * @prev_mm:    store/restore stolen mm_struct while switching to/from efi_mm
 */
struct efi_scratch {
	u64			phys_stack;
	struct mm_struct	*prev_mm;
} __packed;

#define arch_efi_call_virt_setup()					\
({									\
	efi_sync_low_kernel_mappings();					\
	kernel_fpu_begin();						\
	firmware_restrict_branch_speculation_start();			\
									\
	if (!efi_enabled(EFI_OLD_MEMMAP))				\
		efi_switch_mm(&efi_mm);					\
})

#define arch_efi_call_virt(p, f, args...)				\
	efi_call((void *)p->f, args)					\

#define arch_efi_call_virt_teardown()					\
({									\
	if (!efi_enabled(EFI_OLD_MEMMAP))				\
		efi_switch_mm(efi_scratch.prev_mm);			\
									\
	firmware_restrict_branch_speculation_end();			\
	kernel_fpu_end();						\
})

extern void __iomem *__init efi_ioremap(unsigned long addr, unsigned long size,
					u32 type, u64 attribute);

#ifdef CONFIG_KASAN
/*
 * CONFIG_KASAN may redefine memset to __memset.  __memset function is present
 * only in kernel binary.  Since the EFI stub linked into a separate binary it
 * doesn't have __memset().  So we should use standard memset from
 * arch/x86/boot/compressed/string.c.  The same applies to memcpy and memmove.
 */
#undef memcpy
#undef memset
#undef memmove
#endif

#endif /* CONFIG_X86_32 */

extern struct efi_scratch efi_scratch;
extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable);
extern int __init efi_memblock_x86_reserve_range(void);
extern pgd_t * __init efi_call_phys_prolog(void);
extern void __init efi_call_phys_epilog(pgd_t *save_pgd);
extern void __init efi_print_memmap(void);
extern void __init efi_memory_uc(u64 addr, unsigned long size);
extern void __init efi_map_region(efi_memory_desc_t *md);
extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
extern void efi_sync_low_kernel_mappings(void);
extern int __init efi_alloc_page_tables(void);
extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
extern void __init old_map_region(efi_memory_desc_t *md);
extern void __init runtime_code_page_mkexec(void);
extern void __init efi_runtime_update_mappings(void);
extern void __init efi_dump_pagetable(void);
extern void __init efi_apply_memmap_quirks(void);
extern int __init efi_reuse_config(u64 tables, int nr_tables);
extern void efi_delete_dummy_variable(void);
extern void efi_switch_mm(struct mm_struct *mm);

struct efi_setup_data {
	u64 fw_vendor;
	u64 runtime;
	u64 tables;
	u64 smbios;
	u64 reserved[8];
};

extern u64 efi_setup;

#ifdef CONFIG_EFI

static inline bool efi_is_native(void)
{
	return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
}

static inline bool efi_runtime_supported(void)
{
	if (efi_is_native())
		return true;

	if (IS_ENABLED(CONFIG_EFI_MIXED) && !efi_enabled(EFI_OLD_MEMMAP))
		return true;

	return false;
}

extern struct console early_efi_console;
extern void parse_efi_setup(u64 phys_addr, u32 data_len);

extern void efifb_setup_from_dmi(struct screen_info *si, const char *opt);

#ifdef CONFIG_EFI_MIXED
extern void efi_thunk_runtime_setup(void);
extern efi_status_t efi_thunk_set_virtual_address_map(
	void *phys_set_virtual_address_map,
	unsigned long memory_map_size,
	unsigned long descriptor_size,
	u32 descriptor_version,
	efi_memory_desc_t *virtual_map);
#else
static inline void efi_thunk_runtime_setup(void) {}
static inline efi_status_t efi_thunk_set_virtual_address_map(
	void *phys_set_virtual_address_map,
	unsigned long memory_map_size,
	unsigned long descriptor_size,
	u32 descriptor_version,
	efi_memory_desc_t *virtual_map)
{
	return EFI_SUCCESS;
}
#endif /* CONFIG_EFI_MIXED */


/* arch specific definitions used by the stub code */

struct efi_config {
	u64 image_handle;
	u64 table;
	u64 runtime_services;
	u64 boot_services;
	u64 text_output;
	efi_status_t (*call)(unsigned long, ...);
	bool is64;
} __packed;

__pure const struct efi_config *__efi_early(void);

static inline bool efi_is_64bit(void)
{
	if (!IS_ENABLED(CONFIG_X86_64))
		return false;

	if (!IS_ENABLED(CONFIG_EFI_MIXED))
		return true;

	return __efi_early()->is64;
}

#define efi_table_attr(table, attr, instance)				\
	(efi_is_64bit() ?						\
		((table##_64_t *)(unsigned long)instance)->attr :	\
		((table##_32_t *)(unsigned long)instance)->attr)

#define efi_call_proto(protocol, f, instance, ...)			\
	__efi_early()->call(efi_table_attr(protocol, f, instance),	\
		instance, ##__VA_ARGS__)

#define efi_call_early(f, ...)						\
	__efi_early()->call(efi_table_attr(efi_boot_services, f,	\
		__efi_early()->boot_services), __VA_ARGS__)

#define __efi_call_early(f, ...)					\
	__efi_early()->call((unsigned long)f, __VA_ARGS__);

#define efi_call_runtime(f, ...)					\
	__efi_early()->call(efi_table_attr(efi_runtime_services, f,	\
		__efi_early()->runtime_services), __VA_ARGS__)

extern bool efi_reboot_required(void);

#else
static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
static inline bool efi_reboot_required(void)
{
	return false;
}
#endif /* CONFIG_EFI */

#endif /* _ASM_X86_EFI_H */