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 __f(args); \ 35 }) 36 37 #define arch_efi_call_virt_teardown() \ 38 ({ \ 39 __efi_fpsimd_end(); \ 40 efi_virtmap_unload(); \ 41 }) 42 43 #define ARCH_EFI_IRQ_FLAGS_MASK (PSR_D_BIT | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT) 44 45 /* arch specific definitions used by the stub code */ 46 47 /* 48 * AArch64 requires the DTB to be 8-byte aligned in the first 512MiB from 49 * start of kernel and may not cross a 2MiB boundary. We set alignment to 50 * 2MiB so we know it won't cross a 2MiB boundary. 51 */ 52 #define EFI_FDT_ALIGN SZ_2M /* used by allocate_new_fdt_and_exit_boot() */ 53 54 /* 55 * In some configurations (e.g. VMAP_STACK && 64K pages), stacks built into the 56 * kernel need greater alignment than we require the segments to be padded to. 57 */ 58 #define EFI_KIMG_ALIGN \ 59 (SEGMENT_ALIGN > THREAD_ALIGN ? SEGMENT_ALIGN : THREAD_ALIGN) 60 61 /* on arm64, the FDT may be located anywhere in system RAM */ 62 static inline unsigned long efi_get_max_fdt_addr(unsigned long dram_base) 63 { 64 return ULONG_MAX; 65 } 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 - 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.txt, 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 dram_base, 78 unsigned long image_addr) 79 { 80 return (image_addr & ~(SZ_1G - 1UL)) + (1UL << (VA_BITS - 1)); 81 } 82 83 #define efi_call_early(f, ...) sys_table_arg->boottime->f(__VA_ARGS__) 84 #define __efi_call_early(f, ...) f(__VA_ARGS__) 85 #define efi_call_runtime(f, ...) sys_table_arg->runtime->f(__VA_ARGS__) 86 #define efi_is_64bit() (true) 87 88 #define efi_call_proto(protocol, f, instance, ...) \ 89 ((protocol##_t *)instance)->f(instance, ##__VA_ARGS__) 90 91 #define alloc_screen_info(x...) &screen_info 92 #define free_screen_info(x...) 93 94 /* redeclare as 'hidden' so the compiler will generate relative references */ 95 extern struct screen_info screen_info __attribute__((__visibility__("hidden"))); 96 97 static inline void efifb_setup_from_dmi(struct screen_info *si, const char *opt) 98 { 99 } 100 101 #define EFI_ALLOC_ALIGN SZ_64K 102 103 /* 104 * On ARM systems, virtually remapped UEFI runtime services are set up in two 105 * distinct stages: 106 * - The stub retrieves the final version of the memory map from UEFI, populates 107 * the virt_addr fields and calls the SetVirtualAddressMap() [SVAM] runtime 108 * service to communicate the new mapping to the firmware (Note that the new 109 * mapping is not live at this time) 110 * - During an early initcall(), the EFI system table is permanently remapped 111 * and the virtual remapping of the UEFI Runtime Services regions is loaded 112 * into a private set of page tables. If this all succeeds, the Runtime 113 * Services are enabled and the EFI_RUNTIME_SERVICES bit set. 114 */ 115 116 static inline void efi_set_pgd(struct mm_struct *mm) 117 { 118 __switch_mm(mm); 119 120 if (system_uses_ttbr0_pan()) { 121 if (mm != current->active_mm) { 122 /* 123 * Update the current thread's saved ttbr0 since it is 124 * restored as part of a return from exception. Set 125 * the hardware TTBR0_EL1 using cpu_switch_mm() 126 * directly to enable potential errata workarounds. 127 */ 128 update_saved_ttbr0(current, mm); 129 cpu_switch_mm(mm->pgd, mm); 130 } else { 131 /* 132 * Defer the switch to the current thread's TTBR0_EL1 133 * until uaccess_enable(). Restore the current 134 * thread's saved ttbr0 corresponding to its active_mm 135 */ 136 cpu_set_reserved_ttbr0(); 137 update_saved_ttbr0(current, current->active_mm); 138 } 139 } 140 } 141 142 void efi_virtmap_load(void); 143 void efi_virtmap_unload(void); 144 145 #endif /* _ASM_EFI_H */ 146