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 /* arch specific definitions used by the stub code */ 48 49 /* 50 * AArch64 requires the DTB to be 8-byte aligned in the first 512MiB from 51 * start of kernel and may not cross a 2MiB boundary. We set alignment to 52 * 2MiB so we know it won't cross a 2MiB boundary. 53 */ 54 #define EFI_FDT_ALIGN SZ_2M /* used by allocate_new_fdt_and_exit_boot() */ 55 56 /* 57 * In some configurations (e.g. VMAP_STACK && 64K pages), stacks built into the 58 * kernel need greater alignment than we require the segments to be padded to. 59 */ 60 #define EFI_KIMG_ALIGN \ 61 (SEGMENT_ALIGN > THREAD_ALIGN ? SEGMENT_ALIGN : THREAD_ALIGN) 62 63 /* on arm64, the FDT may be located anywhere in system RAM */ 64 static inline unsigned long efi_get_max_fdt_addr(unsigned long dram_base) 65 { 66 return ULONG_MAX; 67 } 68 69 /* 70 * On arm64, we have to ensure that the initrd ends up in the linear region, 71 * which is a 1 GB aligned region of size '1UL << (VA_BITS - 1)' that is 72 * guaranteed to cover the kernel Image. 73 * 74 * Since the EFI stub is part of the kernel Image, we can relax the 75 * usual requirements in Documentation/arm64/booting.txt, which still 76 * apply to other bootloaders, and are required for some kernel 77 * configurations. 78 */ 79 static inline unsigned long efi_get_max_initrd_addr(unsigned long dram_base, 80 unsigned long image_addr) 81 { 82 return (image_addr & ~(SZ_1G - 1UL)) + (1UL << (VA_BITS - 1)); 83 } 84 85 #define efi_call_early(f, ...) sys_table_arg->boottime->f(__VA_ARGS__) 86 #define __efi_call_early(f, ...) f(__VA_ARGS__) 87 #define efi_call_runtime(f, ...) sys_table_arg->runtime->f(__VA_ARGS__) 88 #define efi_is_64bit() (true) 89 90 #define efi_call_proto(protocol, f, instance, ...) \ 91 ((protocol##_t *)instance)->f(instance, ##__VA_ARGS__) 92 93 #define alloc_screen_info(x...) &screen_info 94 #define free_screen_info(x...) 95 96 /* redeclare as 'hidden' so the compiler will generate relative references */ 97 extern struct screen_info screen_info __attribute__((__visibility__("hidden"))); 98 99 static inline void efifb_setup_from_dmi(struct screen_info *si, const char *opt) 100 { 101 } 102 103 #define EFI_ALLOC_ALIGN SZ_64K 104 105 /* 106 * On ARM systems, virtually remapped UEFI runtime services are set up in two 107 * distinct stages: 108 * - The stub retrieves the final version of the memory map from UEFI, populates 109 * the virt_addr fields and calls the SetVirtualAddressMap() [SVAM] runtime 110 * service to communicate the new mapping to the firmware (Note that the new 111 * mapping is not live at this time) 112 * - During an early initcall(), the EFI system table is permanently remapped 113 * and the virtual remapping of the UEFI Runtime Services regions is loaded 114 * into a private set of page tables. If this all succeeds, the Runtime 115 * Services are enabled and the EFI_RUNTIME_SERVICES bit set. 116 */ 117 118 static inline void efi_set_pgd(struct mm_struct *mm) 119 { 120 __switch_mm(mm); 121 122 if (system_uses_ttbr0_pan()) { 123 if (mm != current->active_mm) { 124 /* 125 * Update the current thread's saved ttbr0 since it is 126 * restored as part of a return from exception. Enable 127 * access to the valid TTBR0_EL1 and invoke the errata 128 * workaround directly since there is no return from 129 * exception when invoking the EFI run-time services. 130 */ 131 update_saved_ttbr0(current, mm); 132 uaccess_ttbr0_enable(); 133 post_ttbr_update_workaround(); 134 } else { 135 /* 136 * Defer the switch to the current thread's TTBR0_EL1 137 * until uaccess_enable(). Restore the current 138 * thread's saved ttbr0 corresponding to its active_mm 139 */ 140 uaccess_ttbr0_disable(); 141 update_saved_ttbr0(current, current->active_mm); 142 } 143 } 144 } 145 146 void efi_virtmap_load(void); 147 void efi_virtmap_unload(void); 148 149 #endif /* _ASM_EFI_H */ 150