LXR linux/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
  36extern unsigned long asmlinkage 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
  55extern u64 asmlinkage 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 */
  62struct 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
  97extern 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
 114extern struct efi_scratch efi_scratch;
 115extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable);
 116extern int __init efi_memblock_x86_reserve_range(void);
 117extern pgd_t * __init efi_call_phys_prolog(void);
 118extern void __init efi_call_phys_epilog(pgd_t *save_pgd);
 119extern void __init efi_print_memmap(void);
 120extern void __init efi_memory_uc(u64 addr, unsigned long size);
 121extern void __init efi_map_region(efi_memory_desc_t *md);
 122extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
 123extern void efi_sync_low_kernel_mappings(void);
 124extern int __init efi_alloc_page_tables(void);
 125extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
 126extern void __init old_map_region(efi_memory_desc_t *md);
 127extern void __init runtime_code_page_mkexec(void);
 128extern void __init efi_runtime_update_mappings(void);
 129extern void __init efi_dump_pagetable(void);
 130extern void __init efi_apply_memmap_quirks(void);
 131extern int __init efi_reuse_config(u64 tables, int nr_tables);
 132extern void efi_delete_dummy_variable(void);
 133
 134struct efi_setup_data {
 135        u64 fw_vendor;
 136        u64 runtime;
 137        u64 tables;
 138        u64 smbios;
 139        u64 reserved[8];
 140};
 141
 142extern u64 efi_setup;
 143
 144#ifdef CONFIG_EFI
 145
 146static inline bool efi_is_native(void)
 147{
 148        return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
 149}
 150
 151static 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
 162extern struct console early_efi_console;
 163extern void parse_efi_setup(u64 phys_addr, u32 data_len);
 164
 165extern void efifb_setup_from_dmi(struct screen_info *si, const char *opt);
 166
 167#ifdef CONFIG_EFI_MIXED
 168extern void efi_thunk_runtime_setup(void);
 169extern 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
 176static inline void efi_thunk_runtime_setup(void) {}
 177static 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
 191struct efi_config {
 192        u64 image_handle;
 193        u64 table;
 194        u64 boot_services;
 195        u64 text_output;
 196        efi_status_t (*call)(unsigned long, ...);
 197        bool is64;
 198} __packed;
 199
 200__pure const struct efi_config *__efi_early(void);
 201
 202static inline bool efi_is_64bit(void)
 203{
 204        if (!IS_ENABLED(CONFIG_X86_64))
 205                return false;
 206
 207        if (!IS_ENABLED(CONFIG_EFI_MIXED))
 208                return true;
 209
 210        return __efi_early()->is64;
 211}
 212
 213#define efi_table_attr(table, attr, instance)                           \
 214        (efi_is_64bit() ?                                               \
 215                ((table##_64_t *)(unsigned long)instance)->attr :       \
 216                ((table##_32_t *)(unsigned long)instance)->attr)
 217
 218#define efi_call_proto(protocol, f, instance, ...)                      \
 219        __efi_early()->call(efi_table_attr(protocol, f, instance),      \
 220                instance, ##__VA_ARGS__)
 221
 222#define efi_call_early(f, ...)                                          \
 223        __efi_early()->call(efi_table_attr(efi_boot_services, f,        \
 224                __efi_early()->boot_services), __VA_ARGS__)
 225
 226#define __efi_call_early(f, ...)                                        \
 227        __efi_early()->call((unsigned long)f, __VA_ARGS__);
 228
 229extern bool efi_reboot_required(void);
 230
 231#else
 232static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
 233static inline bool efi_reboot_required(void)
 234{
 235        return false;
 236}
 237#endif /* CONFIG_EFI */
 238
 239#endif /* _ASM_X86_EFI_H */
 240