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/tlb.h>
   7
   8 /*
   9  * We map the EFI regions needed for runtime services non-contiguously,
  10  * with preserved alignment on virtual addresses starting from -4G down
  11  * for a total max space of 64G. This way, we provide for stable runtime
  12  * services addresses across kernels so that a kexec'd kernel can still
  13  * use them.
  14  *
  15  * This is the main reason why we're doing stable VA mappings for RT
  16  * services.
  17  *
  18  * This flag is used in conjuction with a chicken bit called
  19  * "efi=old_map" which can be used as a fallback to the old runtime
  20  * services mapping method in case there's some b0rkage with a
  21  * particular EFI implementation (haha, it is hard to hold up the
  22  * sarcasm here...).
  23  */
  24 #define EFI_OLD_MEMMAP          EFI_ARCH_1
  25
  26 #define EFI32_LOADER_SIGNATURE  "EL32"
  27 #define EFI64_LOADER_SIGNATURE  "EL64"
  28
  29 #define MAX_CMDLINE_ADDRESS     UINT_MAX
  30
  31 #ifdef CONFIG_X86_32
  32
  33
  34 extern unsigned long asmlinkage efi_call_phys(void *, ...);
  35
  36 /*
  37  * Wrap all the virtual calls in a way that forces the parameters on the stack.
  38  */
  39
  40 /* Use this macro if your virtual returns a non-void value */
  41 #define efi_call_virt(f, args...) \
  42 ({                                                                      \
  43         efi_status_t __s;                                               \
  44         kernel_fpu_begin();                                             \
  45         __s = ((efi_##f##_t __attribute__((regparm(0)))*)               \
  46                 efi.systab->runtime->f)(args);                          \
  47         kernel_fpu_end();                                               \
  48         __s;                                                            \
  49 })
  50
  51 /* Use this macro if your virtual call does not return any value */
  52 #define __efi_call_virt(f, args...) \
  53 ({                                                                      \
  54         kernel_fpu_begin();                                             \
  55         ((efi_##f##_t __attribute__((regparm(0)))*)                     \
  56                 efi.systab->runtime->f)(args);                          \
  57         kernel_fpu_end();                                               \
  58 })
  59
  60 #define efi_ioremap(addr, size, type, attr)     ioremap_cache(addr, size)
  61
  62 #else /* !CONFIG_X86_32 */
  63
  64 #define EFI_LOADER_SIGNATURE    "EL64"
  65
  66 extern u64 asmlinkage efi_call(void *fp, ...);
  67
  68 #define efi_call_phys(f, args...)               efi_call((f), args)
  69
  70 /*
  71  * Scratch space used for switching the pagetable in the EFI stub
  72  */
  73 struct efi_scratch {
  74         u64     r15;
  75         u64     prev_cr3;
  76         pgd_t   *efi_pgt;
  77         bool    use_pgd;
  78         u64     phys_stack;
  79 } __packed;
  80
  81 #define efi_call_virt(f, ...)                                           \
  82 ({                                                                      \
  83         efi_status_t __s;                                               \
  84                                                                         \
  85         efi_sync_low_kernel_mappings();                                 \
  86         preempt_disable();                                              \
  87         __kernel_fpu_begin();                                           \
  88                                                                         \
  89         if (efi_scratch.use_pgd) {                                      \
  90                 efi_scratch.prev_cr3 = read_cr3();                      \
  91                 write_cr3((unsigned long)efi_scratch.efi_pgt);          \
  92                 __flush_tlb_all();                                      \
  93         }                                                               \
  94                                                                         \
  95         __s = efi_call((void *)efi.systab->runtime->f, __VA_ARGS__);    \
  96                                                                         \
  97         if (efi_scratch.use_pgd) {                                      \
  98                 write_cr3(efi_scratch.prev_cr3);                        \
  99                 __flush_tlb_all();                                      \
 100         }                                                               \
 101                                                                         \
 102         __kernel_fpu_end();                                             \
 103         preempt_enable();                                               \
 104         __s;                                                            \
 105 })
 106
 107 /*
 108  * All X86_64 virt calls return non-void values. Thus, use non-void call for
 109  * virt calls that would be void on X86_32.
 110  */
 111 #define __efi_call_virt(f, args...) efi_call_virt(f, args)
 112
 113 extern void __iomem *__init efi_ioremap(unsigned long addr, unsigned long size,
 114                                         u32 type, u64 attribute);
 115
 116 #ifdef CONFIG_KASAN
 117 /*
 118  * CONFIG_KASAN may redefine memset to __memset.  __memset function is present
 119  * only in kernel binary.  Since the EFI stub linked into a separate binary it
 120  * doesn't have __memset().  So we should use standard memset from
 121  * arch/x86/boot/compressed/string.c.  The same applies to memcpy and memmove.
 122  */
 123 #undef memcpy
 124 #undef memset
 125 #undef memmove
 126 #endif
 127
 128 #endif /* CONFIG_X86_32 */
 129
 130 extern struct efi_scratch efi_scratch;
 131 extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable);
 132 extern int __init efi_memblock_x86_reserve_range(void);
 133 extern pgd_t * __init efi_call_phys_prolog(void);
 134 extern void __init efi_call_phys_epilog(pgd_t *save_pgd);
 135 extern void __init efi_print_memmap(void);
 136 extern void __init efi_unmap_memmap(void);
 137 extern void __init efi_memory_uc(u64 addr, unsigned long size);
 138 extern void __init efi_map_region(efi_memory_desc_t *md);
 139 extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
 140 extern void efi_sync_low_kernel_mappings(void);
 141 extern int __init efi_alloc_page_tables(void);
 142 extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
 143 extern void __init efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages);
 144 extern void __init old_map_region(efi_memory_desc_t *md);
 145 extern void __init runtime_code_page_mkexec(void);
 146 extern void __init efi_runtime_update_mappings(void);
 147 extern void __init efi_dump_pagetable(void);
 148 extern void __init efi_apply_memmap_quirks(void);
 149 extern int __init efi_reuse_config(u64 tables, int nr_tables);
 150 extern void efi_delete_dummy_variable(void);
 151
 152 struct efi_setup_data {
 153         u64 fw_vendor;
 154         u64 runtime;
 155         u64 tables;
 156         u64 smbios;
 157         u64 reserved[8];
 158 };
 159
 160 extern u64 efi_setup;
 161
 162 #ifdef CONFIG_EFI
 163
 164 static inline bool efi_is_native(void)
 165 {
 166         return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
 167 }
 168
 169 static inline bool efi_runtime_supported(void)
 170 {
 171         if (efi_is_native())
 172                 return true;
 173
 174         if (IS_ENABLED(CONFIG_EFI_MIXED) && !efi_enabled(EFI_OLD_MEMMAP))
 175                 return true;
 176
 177         return false;
 178 }
 179
 180 extern struct console early_efi_console;
 181 extern void parse_efi_setup(u64 phys_addr, u32 data_len);
 182
 183 #ifdef CONFIG_EFI_MIXED
 184 extern void efi_thunk_runtime_setup(void);
 185 extern efi_status_t efi_thunk_set_virtual_address_map(
 186         void *phys_set_virtual_address_map,
 187         unsigned long memory_map_size,
 188         unsigned long descriptor_size,
 189         u32 descriptor_version,
 190         efi_memory_desc_t *virtual_map);
 191 #else
 192 static inline void efi_thunk_runtime_setup(void) {}
 193 static inline efi_status_t efi_thunk_set_virtual_address_map(
 194         void *phys_set_virtual_address_map,
 195         unsigned long memory_map_size,
 196         unsigned long descriptor_size,
 197         u32 descriptor_version,
 198         efi_memory_desc_t *virtual_map)
 199 {
 200         return EFI_SUCCESS;
 201 }
 202 #endif /* CONFIG_EFI_MIXED */
 203
 204
 205 /* arch specific definitions used by the stub code */
 206
 207 struct efi_config {
 208         u64 image_handle;
 209         u64 table;
 210         u64 allocate_pool;
 211         u64 allocate_pages;
 212         u64 get_memory_map;
 213         u64 free_pool;
 214         u64 free_pages;
 215         u64 locate_handle;
 216         u64 handle_protocol;
 217         u64 exit_boot_services;
 218         u64 text_output;
 219         efi_status_t (*call)(unsigned long, ...);
 220         bool is64;
 221 } __packed;
 222
 223 __pure const struct efi_config *__efi_early(void);
 224
 225 #define efi_call_early(f, ...)                                          \
 226         __efi_early()->call(__efi_early()->f, __VA_ARGS__);
 227
 228 extern bool efi_reboot_required(void);
 229
 230 #else
 231 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
 232 static inline bool efi_reboot_required(void)
 233 {
 234         return false;
 235 }
 236 #endif /* CONFIG_EFI */
 237
 238 #endif /* _ASM_X86_EFI_H */