arch/x86/include/asm/efi.h

   1 #ifndef _ASM_X86_EFI_H
   2 #define _ASM_X86_EFI_H
   3
   4 #include <asm/fpu/api.h>
   5 #include <asm/pgtable.h>
   6 #include <asm/processor-flags.h>
   7 #include <asm/tlb.h>
   8
   9 /*
  10  * We map the EFI regions needed for runtime services non-contiguously,
  11  * with preserved alignment on virtual addresses starting from -4G down
  12  * for a total max space of 64G. This way, we provide for stable runtime
  13  * services addresses across kernels so that a kexec'd kernel can still
  14  * use them.
  15  *
  16  * This is the main reason why we're doing stable VA mappings for RT
  17  * services.
  18  *
  19  * This flag is used in conjuction with a chicken bit called
  20  * "efi=old_map" which can be used as a fallback to the old runtime
  21  * services mapping method in case there's some b0rkage with a
  22  * particular EFI implementation (haha, it is hard to hold up the
  23  * sarcasm here...).
  24  */
  25 #define EFI_OLD_MEMMAP          EFI_ARCH_1
  26
  27 #define EFI32_LOADER_SIGNATURE  "EL32"
  28 #define EFI64_LOADER_SIGNATURE  "EL64"
  29
  30 #define MAX_CMDLINE_ADDRESS     UINT_MAX
  31
  32 #define ARCH_EFI_IRQ_FLAGS_MASK X86_EFLAGS_IF
  33
  34 #ifdef CONFIG_X86_32
  35
  36 extern asmlinkage unsigned long efi_call_phys(void *, ...);
  37
  38 #define arch_efi_call_virt_setup()      kernel_fpu_begin()
  39 #define arch_efi_call_virt_teardown()   kernel_fpu_end()
  40
  41 /*
  42  * Wrap all the virtual calls in a way that forces the parameters on the stack.
  43  */
  44 #define arch_efi_call_virt(p, f, args...)                               \
  45 ({                                                                      \
  46         ((efi_##f##_t __attribute__((regparm(0)))*) p->f)(args);        \
  47 })
  48
  49 #define efi_ioremap(addr, size, type, attr)     ioremap_cache(addr, size)
  50
  51 #else /* !CONFIG_X86_32 */
  52
  53 #define EFI_LOADER_SIGNATURE    "EL64"
  54
  55 extern asmlinkage u64 efi_call(void *fp, ...);
  56
  57 #define efi_call_phys(f, args...)               efi_call((f), args)
  58
  59 /*
  60  * Scratch space used for switching the pagetable in the EFI stub
  61  */
  62 struct efi_scratch {
  63         u64     r15;
  64         u64     prev_cr3;
  65         pgd_t   *efi_pgt;
  66         bool    use_pgd;
  67         u64     phys_stack;
  68 } __packed;
  69
  70 #define arch_efi_call_virt_setup()                                      \
  71 ({                                                                      \
  72         efi_sync_low_kernel_mappings();                                 \
  73         preempt_disable();                                              \
  74         __kernel_fpu_begin();                                           \
  75                                                                         \
  76         if (efi_scratch.use_pgd) {                                      \
  77                 efi_scratch.prev_cr3 = __read_cr3();                    \
  78                 write_cr3((unsigned long)efi_scratch.efi_pgt);          \
  79                 __flush_tlb_all();                                      \
  80         }                                                               \
  81 })
  82
  83 #define arch_efi_call_virt(p, f, args...)                               \
  84         efi_call((void *)p->f, args)                                    \
  85
  86 #define arch_efi_call_virt_teardown()                                   \
  87 ({                                                                      \
  88         if (efi_scratch.use_pgd) {                                      \
  89                 write_cr3(efi_scratch.prev_cr3);                        \
  90                 __flush_tlb_all();                                      \
  91         }                                                               \
  92                                                                         \
  93         __kernel_fpu_end();                                             \
  94         preempt_enable();                                               \
  95 })
  96
  97 extern void __iomem *__init efi_ioremap(unsigned long addr, unsigned long size,
  98                                         u32 type, u64 attribute);
  99
 100 #ifdef CONFIG_KASAN
 101 /*
 102  * CONFIG_KASAN may redefine memset to __memset.  __memset function is present
 103  * only in kernel binary.  Since the EFI stub linked into a separate binary it
 104  * doesn't have __memset().  So we should use standard memset from
 105  * arch/x86/boot/compressed/string.c.  The same applies to memcpy and memmove.
 106  */
 107 #undef memcpy
 108 #undef memset
 109 #undef memmove
 110 #endif
 111
 112 #endif /* CONFIG_X86_32 */
 113
 114 extern struct efi_scratch efi_scratch;
 115 extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable);
 116 extern int __init efi_memblock_x86_reserve_range(void);
 117 extern pgd_t * __init efi_call_phys_prolog(void);
 118 extern void __init efi_call_phys_epilog(pgd_t *save_pgd);
 119 extern void __init efi_print_memmap(void);
 120 extern void __init efi_memory_uc(u64 addr, unsigned long size);
 121 extern void __init efi_map_region(efi_memory_desc_t *md);
 122 extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
 123 extern void efi_sync_low_kernel_mappings(void);
 124 extern int __init efi_alloc_page_tables(void);
 125 extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
 126 extern void __init old_map_region(efi_memory_desc_t *md);
 127 extern void __init runtime_code_page_mkexec(void);
 128 extern void __init efi_runtime_update_mappings(void);
 129 extern void __init efi_dump_pagetable(void);
 130 extern void __init efi_apply_memmap_quirks(void);
 131 extern int __init efi_reuse_config(u64 tables, int nr_tables);
 132 extern void efi_delete_dummy_variable(void);
 133
 134 struct efi_setup_data {
 135         u64 fw_vendor;
 136         u64 runtime;
 137         u64 tables;
 138         u64 smbios;
 139         u64 reserved[8];
 140 };
 141
 142 extern u64 efi_setup;
 143
 144 #ifdef CONFIG_EFI
 145
 146 static inline bool efi_is_native(void)
 147 {
 148         return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
 149 }
 150
 151 static inline bool efi_runtime_supported(void)
 152 {
 153         if (efi_is_native())
 154                 return true;
 155
 156         if (IS_ENABLED(CONFIG_EFI_MIXED) && !efi_enabled(EFI_OLD_MEMMAP))
 157                 return true;
 158
 159         return false;
 160 }
 161
 162 extern struct console early_efi_console;
 163 extern void parse_efi_setup(u64 phys_addr, u32 data_len);
 164
 165 extern void efifb_setup_from_dmi(struct screen_info *si, const char *opt);
 166
 167 #ifdef CONFIG_EFI_MIXED
 168 extern void efi_thunk_runtime_setup(void);
 169 extern efi_status_t efi_thunk_set_virtual_address_map(
 170         void *phys_set_virtual_address_map,
 171         unsigned long memory_map_size,
 172         unsigned long descriptor_size,
 173         u32 descriptor_version,
 174         efi_memory_desc_t *virtual_map);
 175 #else
 176 static inline void efi_thunk_runtime_setup(void) {}
 177 static inline efi_status_t efi_thunk_set_virtual_address_map(
 178         void *phys_set_virtual_address_map,
 179         unsigned long memory_map_size,
 180         unsigned long descriptor_size,
 181         u32 descriptor_version,
 182         efi_memory_desc_t *virtual_map)
 183 {
 184         return EFI_SUCCESS;
 185 }
 186 #endif /* CONFIG_EFI_MIXED */
 187
 188
 189 /* arch specific definitions used by the stub code */
 190
 191 struct efi_config {
 192         u64 image_handle;
 193         u64 table;
 194         u64 runtime_services;
 195         u64 boot_services;
 196         u64 text_output;
 197         efi_status_t (*call)(unsigned long, ...);
 198         bool is64;
 199 } __packed;
 200
 201 __pure const struct efi_config *__efi_early(void);
 202
 203 static inline bool efi_is_64bit(void)
 204 {
 205         if (!IS_ENABLED(CONFIG_X86_64))
 206                 return false;
 207
 208         if (!IS_ENABLED(CONFIG_EFI_MIXED))
 209                 return true;
 210
 211         return __efi_early()->is64;
 212 }
 213
 214 #define efi_table_attr(table, attr, instance)                           \
 215         (efi_is_64bit() ?                                               \
 216                 ((table##_64_t *)(unsigned long)instance)->attr :       \
 217                 ((table##_32_t *)(unsigned long)instance)->attr)
 218
 219 #define efi_call_proto(protocol, f, instance, ...)                      \
 220         __efi_early()->call(efi_table_attr(protocol, f, instance),      \
 221                 instance, ##__VA_ARGS__)
 222
 223 #define efi_call_early(f, ...)                                          \
 224         __efi_early()->call(efi_table_attr(efi_boot_services, f,        \
 225                 __efi_early()->boot_services), __VA_ARGS__)
 226
 227 #define __efi_call_early(f, ...)                                        \
 228         __efi_early()->call((unsigned long)f, __VA_ARGS__);
 229
 230 #define efi_call_runtime(f, ...)                                        \
 231         __efi_early()->call(efi_table_attr(efi_runtime_services, f,     \
 232                 __efi_early()->runtime_services), __VA_ARGS__)
 233
 234 extern bool efi_reboot_required(void);
 235
 236 #else
 237 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
 238 static inline bool efi_reboot_required(void)
 239 {
 240         return false;
 241 }
 242 #endif /* CONFIG_EFI */
 243
 244 #endif /* _ASM_X86_EFI_H */