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 18 bool efi_runtime_fixup_exception(struct pt_regs *regs, const char *msg); 19 #else 20 #define efi_init() 21 22 static inline 23 bool efi_runtime_fixup_exception(struct pt_regs *regs, const char *msg) 24 { 25 return false; 26 } 27 #endif 28 29 int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md); 30 int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md); 31 32 #define arch_efi_call_virt_setup() \ 33 ({ \ 34 efi_virtmap_load(); \ 35 __efi_fpsimd_begin(); \ 36 }) 37 38 #undef arch_efi_call_virt 39 #define arch_efi_call_virt(p, f, args...) \ 40 __efi_rt_asm_wrapper((p)->f, #f, args) 41 42 #define arch_efi_call_virt_teardown() \ 43 ({ \ 44 __efi_fpsimd_end(); \ 45 efi_virtmap_unload(); \ 46 }) 47 48 efi_status_t __efi_rt_asm_wrapper(void *, const char *, ...); 49 50 #define ARCH_EFI_IRQ_FLAGS_MASK (PSR_D_BIT | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT) 51 52 /* 53 * Even when Linux uses IRQ priorities for IRQ disabling, EFI does not. 54 * And EFI shouldn't really play around with priority masking as it is not aware 55 * which priorities the OS has assigned to its interrupts. 56 */ 57 #define arch_efi_save_flags(state_flags) \ 58 ((void)((state_flags) = read_sysreg(daif))) 59 60 #define arch_efi_restore_flags(state_flags) write_sysreg(state_flags, daif) 61 62 63 /* arch specific definitions used by the stub code */ 64 65 /* 66 * In some configurations (e.g. VMAP_STACK && 64K pages), stacks built into the 67 * kernel need greater alignment than we require the segments to be padded to. 68 */ 69 #define EFI_KIMG_ALIGN \ 70 (SEGMENT_ALIGN > THREAD_ALIGN ? SEGMENT_ALIGN : THREAD_ALIGN) 71 72 /* 73 * On arm64, we have to ensure that the initrd ends up in the linear region, 74 * which is a 1 GB aligned region of size '1UL << (VA_BITS_MIN - 1)' that is 75 * guaranteed to cover the kernel Image. 76 * 77 * Since the EFI stub is part of the kernel Image, we can relax the 78 * usual requirements in Documentation/arm64/booting.rst, which still 79 * apply to other bootloaders, and are required for some kernel 80 * configurations. 81 */ 82 static inline unsigned long efi_get_max_initrd_addr(unsigned long image_addr) 83 { 84 return (image_addr & ~(SZ_1G - 1UL)) + (1UL << (VA_BITS_MIN - 1)); 85 } 86 87 #define alloc_screen_info(x...) &screen_info 88 89 static inline void free_screen_info(struct screen_info *si) 90 { 91 } 92 93 #define EFI_ALLOC_ALIGN SZ_64K 94 95 /* 96 * On ARM systems, virtually remapped UEFI runtime services are set up in two 97 * distinct stages: 98 * - The stub retrieves the final version of the memory map from UEFI, populates 99 * the virt_addr fields and calls the SetVirtualAddressMap() [SVAM] runtime 100 * service to communicate the new mapping to the firmware (Note that the new 101 * mapping is not live at this time) 102 * - During an early initcall(), the EFI system table is permanently remapped 103 * and the virtual remapping of the UEFI Runtime Services regions is loaded 104 * into a private set of page tables. If this all succeeds, the Runtime 105 * Services are enabled and the EFI_RUNTIME_SERVICES bit set. 106 */ 107 108 static inline void efi_set_pgd(struct mm_struct *mm) 109 { 110 __switch_mm(mm); 111 112 if (system_uses_ttbr0_pan()) { 113 if (mm != current->active_mm) { 114 /* 115 * Update the current thread's saved ttbr0 since it is 116 * restored as part of a return from exception. Enable 117 * access to the valid TTBR0_EL1 and invoke the errata 118 * workaround directly since there is no return from 119 * exception when invoking the EFI run-time services. 120 */ 121 update_saved_ttbr0(current, mm); 122 uaccess_ttbr0_enable(); 123 post_ttbr_update_workaround(); 124 } else { 125 /* 126 * Defer the switch to the current thread's TTBR0_EL1 127 * until uaccess_enable(). Restore the current 128 * thread's saved ttbr0 corresponding to its active_mm 129 */ 130 uaccess_ttbr0_disable(); 131 update_saved_ttbr0(current, current->active_mm); 132 } 133 } 134 } 135 136 void efi_virtmap_load(void); 137 void efi_virtmap_unload(void); 138 139 static inline void efi_capsule_flush_cache_range(void *addr, int size) 140 { 141 dcache_clean_inval_poc((unsigned long)addr, (unsigned long)addr + size); 142 } 143 144 #endif /* _ASM_EFI_H */ 145