arch/arm64/include/asm/efi.h

   1 #ifndef _ASM_EFI_H
   2 #define _ASM_EFI_H
   3
   4 #include <asm/io.h>
   5 #include <asm/mmu_context.h>
   6 #include <asm/neon.h>
   7 #include <asm/tlbflush.h>
   8
   9 #ifdef CONFIG_EFI
  10 extern void efi_init(void);
  11 #else
  12 #define efi_init()
  13 #endif
  14
  15 int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md);
  16
  17 #define efi_set_mapping_permissions     efi_create_mapping
  18
  19 #define efi_call_virt(f, ...)                                           \
  20 ({                                                                      \
  21         efi_##f##_t *__f;                                               \
  22         efi_status_t __s;                                               \
  23                                                                         \
  24         kernel_neon_begin();                                            \
  25         efi_virtmap_load();                                             \
  26         __f = efi.systab->runtime->f;                                   \
  27         __s = __f(__VA_ARGS__);                                         \
  28         efi_virtmap_unload();                                           \
  29         kernel_neon_end();                                              \
  30         __s;                                                            \
  31 })
  32
  33 #define __efi_call_virt(f, ...)                                         \
  34 ({                                                                      \
  35         efi_##f##_t *__f;                                               \
  36                                                                         \
  37         kernel_neon_begin();                                            \
  38         efi_virtmap_load();                                             \
  39         __f = efi.systab->runtime->f;                                   \
  40         __f(__VA_ARGS__);                                               \
  41         efi_virtmap_unload();                                           \
  42         kernel_neon_end();                                              \
  43 })
  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 #define MAX_FDT_OFFSET  SZ_512M
  54
  55 #define efi_call_early(f, ...) sys_table_arg->boottime->f(__VA_ARGS__)
  56
  57 #define EFI_ALLOC_ALIGN         SZ_64K
  58
  59 /*
  60  * On ARM systems, virtually remapped UEFI runtime services are set up in two
  61  * distinct stages:
  62  * - The stub retrieves the final version of the memory map from UEFI, populates
  63  *   the virt_addr fields and calls the SetVirtualAddressMap() [SVAM] runtime
  64  *   service to communicate the new mapping to the firmware (Note that the new
  65  *   mapping is not live at this time)
  66  * - During an early initcall(), the EFI system table is permanently remapped
  67  *   and the virtual remapping of the UEFI Runtime Services regions is loaded
  68  *   into a private set of page tables. If this all succeeds, the Runtime
  69  *   Services are enabled and the EFI_RUNTIME_SERVICES bit set.
  70  */
  71
  72 static inline void efi_set_pgd(struct mm_struct *mm)
  73 {
  74         switch_mm(NULL, mm, NULL);
  75 }
  76
  77 void efi_virtmap_load(void);
  78 void efi_virtmap_unload(void);
  79
  80 #endif /* _ASM_EFI_H */