1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_EFI_H
3 #define _ASM_EFI_H
4
5 #include <asm/boot.h>
6 #include <asm/cpufeature.h>
7 #include <asm/fpsimd.h>
8 #include <asm/io.h>
9 #include <asm/memory.h>
10 #include <asm/mmu_context.h>
11 #include <asm/neon.h>
12 #include <asm/ptrace.h>
13 #include <asm/tlbflush.h>
14
15 #ifdef CONFIG_EFI
16 extern void efi_init(void);
17 #else
18 #define efi_init()
19 #endif
20
21 int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md);
22 int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md);
23
24 #define arch_efi_call_virt_setup() \
25 ({ \
26 efi_virtmap_load(); \
27 __efi_fpsimd_begin(); \
28 })
29
30 #define arch_efi_call_virt(p, f, args...) \
31 ({ \
32 efi_##f##_t *__f; \
33 __f = p->f; \
34 __efi_rt_asm_wrapper(__f, #f, args); \
35 })
36
37 #define arch_efi_call_virt_teardown() \
38 ({ \
39 __efi_fpsimd_end(); \
40 efi_virtmap_unload(); \
41 })
42
43 efi_status_t __efi_rt_asm_wrapper(void *, const char *, ...);
44
45 #define ARCH_EFI_IRQ_FLAGS_MASK (PSR_D_BIT | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT)
46
47 /*
48 * Even when Linux uses IRQ priorities for IRQ disabling, EFI does not.
49 * And EFI shouldn't really play around with priority masking as it is not aware
50 * which priorities the OS has assigned to its interrupts.
51 */
52 #define arch_efi_save_flags(state_flags) \
53 ((void)((state_flags) = read_sysreg(daif)))
54
55 #define arch_efi_restore_flags(state_flags) write_sysreg(state_flags, daif)
56
57
58 /* arch specific definitions used by the stub code */
59
60 /*
61 * In some configurations (e.g. VMAP_STACK && 64K pages), stacks built into the
62 * kernel need greater alignment than we require the segments to be padded to.
63 */
64 #define EFI_KIMG_ALIGN \
65 (SEGMENT_ALIGN > THREAD_ALIGN ? SEGMENT_ALIGN : THREAD_ALIGN)
66
67 /*
68 * On arm64, we have to ensure that the initrd ends up in the linear region,
69 * which is a 1 GB aligned region of size '1UL << (VA_BITS_MIN - 1)' that is
70 * guaranteed to cover the kernel Image.
71 *
72 * Since the EFI stub is part of the kernel Image, we can relax the
73 * usual requirements in Documentation/arm64/booting.rst, which still
74 * apply to other bootloaders, and are required for some kernel
75 * configurations.
76 */
77 static inline unsigned long efi_get_max_initrd_addr(unsigned long image_addr)
78 {
79 return (image_addr & ~(SZ_1G - 1UL)) + (1UL << (VA_BITS_MIN - 1));
80 }
81
82 #define alloc_screen_info(x...) &screen_info
83
84 static inline void free_screen_info(struct screen_info *si)
85 {
86 }
87
88 static inline void efifb_setup_from_dmi(struct screen_info *si, const char *opt)
89 {
90 }
91
92 #define EFI_ALLOC_ALIGN SZ_64K
93
94 /*
95 * On ARM systems, virtually remapped UEFI runtime services are set up in two
96 * distinct stages:
97 * - The stub retrieves the final version of the memory map from UEFI, populates
98 * the virt_addr fields and calls the SetVirtualAddressMap() [SVAM] runtime
99 * service to communicate the new mapping to the firmware (Note that the new
100 * mapping is not live at this time)
101 * - During an early initcall(), the EFI system table is permanently remapped
102 * and the virtual remapping of the UEFI Runtime Services regions is loaded
103 * into a private set of page tables. If this all succeeds, the Runtime
104 * Services are enabled and the EFI_RUNTIME_SERVICES bit set.
105 */
106
107 static inline void efi_set_pgd(struct mm_struct *mm)
108 {
109 __switch_mm(mm);
110
111 if (system_uses_ttbr0_pan()) {
112 if (mm != current->active_mm) {
113 /*
114 * Update the current thread's saved ttbr0 since it is
115 * restored as part of a return from exception. Enable
116 * access to the valid TTBR0_EL1 and invoke the errata
117 * workaround directly since there is no return from
118 * exception when invoking the EFI run-time services.
119 */
120 update_saved_ttbr0(current, mm);
121 uaccess_ttbr0_enable();
122 post_ttbr_update_workaround();
123 } else {
124 /*
125 * Defer the switch to the current thread's TTBR0_EL1
126 * until uaccess_enable(). Restore the current
127 * thread's saved ttbr0 corresponding to its active_mm
128 */
129 uaccess_ttbr0_disable();
130 update_saved_ttbr0(current, current->active_mm);
131 }
132 }
133 }
134
135 void efi_virtmap_load(void);
136 void efi_virtmap_unload(void);
137
138 static inline void efi_capsule_flush_cache_range(void *addr, int size)
139 {
140 dcache_clean_inval_poc((unsigned long)addr, (unsigned long)addr + size);
141 }
142
143 #endif /* _ASM_EFI_H */
144
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