4 #include <asm/cpufeature.h>
6 #include <asm/mmu_context.h>
8 #include <asm/tlbflush.h>
11 extern void efi_init(void);
16 int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md);
18 #define efi_call_virt(f, ...) \
23 kernel_neon_begin(); \
25 __f = efi.systab->runtime->f; \
26 __s = __f(__VA_ARGS__); \
27 efi_virtmap_unload(); \
32 #define __efi_call_virt(f, ...) \
36 kernel_neon_begin(); \
38 __f = efi.systab->runtime->f; \
40 efi_virtmap_unload(); \
44 /* arch specific definitions used by the stub code */
47 * AArch64 requires the DTB to be 8-byte aligned in the first 512MiB from
48 * start of kernel and may not cross a 2MiB boundary. We set alignment to
49 * 2MiB so we know it won't cross a 2MiB boundary.
51 #define EFI_FDT_ALIGN SZ_2M /* used by allocate_new_fdt_and_exit_boot() */
52 #define MAX_FDT_OFFSET SZ_512M
54 #define efi_call_early(f, ...) sys_table_arg->boottime->f(__VA_ARGS__)
56 #define EFI_ALLOC_ALIGN SZ_64K
59 * On ARM systems, virtually remapped UEFI runtime services are set up in two
61 * - The stub retrieves the final version of the memory map from UEFI, populates
62 * the virt_addr fields and calls the SetVirtualAddressMap() [SVAM] runtime
63 * service to communicate the new mapping to the firmware (Note that the new
64 * mapping is not live at this time)
65 * - During an early initcall(), the EFI system table is permanently remapped
66 * and the virtual remapping of the UEFI Runtime Services regions is loaded
67 * into a private set of page tables. If this all succeeds, the Runtime
68 * Services are enabled and the EFI_RUNTIME_SERVICES bit set.
71 static inline void efi_set_pgd(struct mm_struct *mm)
75 if (system_uses_ttbr0_pan()) {
76 if (mm != current->active_mm) {
78 * Update the current thread's saved ttbr0 since it is
79 * restored as part of a return from exception. Set
80 * the hardware TTBR0_EL1 using cpu_switch_mm()
81 * directly to enable potential errata workarounds.
83 update_saved_ttbr0(current, mm);
84 cpu_switch_mm(mm->pgd, mm);
87 * Defer the switch to the current thread's TTBR0_EL1
88 * until uaccess_enable(). Restore the current
89 * thread's saved ttbr0 corresponding to its active_mm
90 * (if different from init_mm).
92 cpu_set_reserved_ttbr0();
93 if (current->active_mm != &init_mm)
94 update_saved_ttbr0(current, current->active_mm);
99 void efi_virtmap_load(void);
100 void efi_virtmap_unload(void);
102 #endif /* _ASM_EFI_H */