1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_X86_EFI_H
3#define _ASM_X86_EFI_H
4
5#include <asm/fpu/api.h>
6#include <asm/pgtable.h>
7#include <asm/processor-flags.h>
8#include <asm/tlb.h>
9#include <asm/nospec-branch.h>
10#include <asm/mmu_context.h>
11
12/*
13 * We map the EFI regions needed for runtime services non-contiguously,
14 * with preserved alignment on virtual addresses starting from -4G down
15 * for a total max space of 64G. This way, we provide for stable runtime
16 * services addresses across kernels so that a kexec'd kernel can still
17 * use them.
18 *
19 * This is the main reason why we're doing stable VA mappings for RT
20 * services.
21 *
22 * This flag is used in conjunction with a chicken bit called
23 * "efi=old_map" which can be used as a fallback to the old runtime
24 * services mapping method in case there's some b0rkage with a
25 * particular EFI implementation (haha, it is hard to hold up the
26 * sarcasm here...).
27 */
28#define EFI_OLD_MEMMAP EFI_ARCH_1
29
30#define EFI32_LOADER_SIGNATURE "EL32"
31#define EFI64_LOADER_SIGNATURE "EL64"
32
33#define MAX_CMDLINE_ADDRESS UINT_MAX
34
35#define ARCH_EFI_IRQ_FLAGS_MASK X86_EFLAGS_IF
36
37#ifdef CONFIG_X86_32
38
39extern asmlinkage unsigned long efi_call_phys(void *, ...);
40
41#define arch_efi_call_virt_setup() \
42({ \
43 kernel_fpu_begin(); \
44 firmware_restrict_branch_speculation_start(); \
45})
46
47#define arch_efi_call_virt_teardown() \
48({ \
49 firmware_restrict_branch_speculation_end(); \
50 kernel_fpu_end(); \
51})
52
53
54/*
55 * Wrap all the virtual calls in a way that forces the parameters on the stack.
56 */
57#define arch_efi_call_virt(p, f, args...) \
58({ \
59 ((efi_##f##_t __attribute__((regparm(0)))*) p->f)(args); \
60})
61
62#define efi_ioremap(addr, size, type, attr) ioremap_cache(addr, size)
63
64#else /* !CONFIG_X86_32 */
65
66#define EFI_LOADER_SIGNATURE "EL64"
67
68extern asmlinkage u64 efi_call(void *fp, ...);
69
70#define efi_call_phys(f, args...) efi_call((f), args)
71
72/*
73 * struct efi_scratch - Scratch space used while switching to/from efi_mm
74 * @phys_stack: stack used during EFI Mixed Mode
75 * @prev_mm: store/restore stolen mm_struct while switching to/from efi_mm
76 */
77struct efi_scratch {
78 u64 phys_stack;
79 struct mm_struct *prev_mm;
80} __packed;
81
82#define arch_efi_call_virt_setup() \
83({ \
84 efi_sync_low_kernel_mappings(); \
85 kernel_fpu_begin(); \
86 firmware_restrict_branch_speculation_start(); \
87 \
88 if (!efi_enabled(EFI_OLD_MEMMAP)) \
89 efi_switch_mm(&efi_mm); \
90})
91
92#define arch_efi_call_virt(p, f, args...) \
93 efi_call((void *)p->f, args) \
94
95#define arch_efi_call_virt_teardown() \
96({ \
97 if (!efi_enabled(EFI_OLD_MEMMAP)) \
98 efi_switch_mm(efi_scratch.prev_mm); \
99 \
100 firmware_restrict_branch_speculation_end(); \
101 kernel_fpu_end(); \
102})
103
104extern void __iomem *__init efi_ioremap(unsigned long addr, unsigned long size,
105 u32 type, u64 attribute);
106
107#ifdef CONFIG_KASAN
108/*
109 * CONFIG_KASAN may redefine memset to __memset. __memset function is present
110 * only in kernel binary. Since the EFI stub linked into a separate binary it
111 * doesn't have __memset(). So we should use standard memset from
112 * arch/x86/boot/compressed/string.c. The same applies to memcpy and memmove.
113 */
114#undef memcpy
115#undef memset
116#undef memmove
117#endif
118
119#endif /* CONFIG_X86_32 */
120
121extern struct efi_scratch efi_scratch;
122extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable);
123extern int __init efi_memblock_x86_reserve_range(void);
124extern pgd_t * __init efi_call_phys_prolog(void);
125extern void __init efi_call_phys_epilog(pgd_t *save_pgd);
126extern void __init efi_print_memmap(void);
127extern void __init efi_memory_uc(u64 addr, unsigned long size);
128extern void __init efi_map_region(efi_memory_desc_t *md);
129extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
130extern void efi_sync_low_kernel_mappings(void);
131extern int __init efi_alloc_page_tables(void);
132extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
133extern void __init old_map_region(efi_memory_desc_t *md);
134extern void __init runtime_code_page_mkexec(void);
135extern void __init efi_runtime_update_mappings(void);
136extern void __init efi_dump_pagetable(void);
137extern void __init efi_apply_memmap_quirks(void);
138extern int __init efi_reuse_config(u64 tables, int nr_tables);
139extern void efi_delete_dummy_variable(void);
140extern void efi_switch_mm(struct mm_struct *mm);
141extern void efi_recover_from_page_fault(unsigned long phys_addr);
142extern void efi_free_boot_services(void);
143extern void efi_reserve_boot_services(void);
144
145struct efi_setup_data {
146 u64 fw_vendor;
147 u64 runtime;
148 u64 tables;
149 u64 smbios;
150 u64 reserved[8];
151};
152
153extern u64 efi_setup;
154
155#ifdef CONFIG_EFI
156
157static inline bool efi_is_native(void)
158{
159 return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
160}
161
162static inline bool efi_runtime_supported(void)
163{
164 if (efi_is_native())
165 return true;
166
167 if (IS_ENABLED(CONFIG_EFI_MIXED) && !efi_enabled(EFI_OLD_MEMMAP))
168 return true;
169
170 return false;
171}
172
173extern void parse_efi_setup(u64 phys_addr, u32 data_len);
174
175extern void efifb_setup_from_dmi(struct screen_info *si, const char *opt);
176
177#ifdef CONFIG_EFI_MIXED
178extern void efi_thunk_runtime_setup(void);
179extern efi_status_t efi_thunk_set_virtual_address_map(
180 void *phys_set_virtual_address_map,
181 unsigned long memory_map_size,
182 unsigned long descriptor_size,
183 u32 descriptor_version,
184 efi_memory_desc_t *virtual_map);
185#else
186static inline void efi_thunk_runtime_setup(void) {}
187static inline efi_status_t efi_thunk_set_virtual_address_map(
188 void *phys_set_virtual_address_map,
189 unsigned long memory_map_size,
190 unsigned long descriptor_size,
191 u32 descriptor_version,
192 efi_memory_desc_t *virtual_map)
193{
194 return EFI_SUCCESS;
195}
196#endif /* CONFIG_EFI_MIXED */
197
198
199/* arch specific definitions used by the stub code */
200
201struct efi_config {
202 u64 image_handle;
203 u64 table;
204 u64 runtime_services;
205 u64 boot_services;
206 u64 text_output;
207 efi_status_t (*call)(unsigned long, ...);
208 bool is64;
209} __packed;
210
211__pure const struct efi_config *__efi_early(void);
212
213static inline bool efi_is_64bit(void)
214{
215 if (!IS_ENABLED(CONFIG_X86_64))
216 return false;
217
218 if (!IS_ENABLED(CONFIG_EFI_MIXED))
219 return true;
220
221 return __efi_early()->is64;
222}
223
224#define efi_table_attr(table, attr, instance) \
225 (efi_is_64bit() ? \
226 ((table##_64_t *)(unsigned long)instance)->attr : \
227 ((table##_32_t *)(unsigned long)instance)->attr)
228
229#define efi_call_proto(protocol, f, instance, ...) \
230 __efi_early()->call(efi_table_attr(protocol, f, instance), \
231 instance, ##__VA_ARGS__)
232
233#define efi_call_early(f, ...) \
234 __efi_early()->call(efi_table_attr(efi_boot_services, f, \
235 __efi_early()->boot_services), __VA_ARGS__)
236
237#define __efi_call_early(f, ...) \
238 __efi_early()->call((unsigned long)f, __VA_ARGS__);
239
240#define efi_call_runtime(f, ...) \
241 __efi_early()->call(efi_table_attr(efi_runtime_services, f, \
242 __efi_early()->runtime_services), __VA_ARGS__)
243
244extern bool efi_reboot_required(void);
245
246#else
247static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
248static inline bool efi_reboot_required(void)
249{
250 return false;
251}
252#endif /* CONFIG_EFI */
253
254#endif /* _ASM_X86_EFI_H */
255