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