root/arch/x86/include/asm/efi.h

INCLUDED FROM

DEFINITIONS

1. efi_is_native
2. efi_runtime_supported
3. efi_thunk_runtime_setup
4. efi_thunk_set_virtual_address_map
5. parse_efi_setup
6. efi_reboot_required

#ifndef _ASM_X86_EFI_H
#define _ASM_X86_EFI_H

#include <asm/i387.h>
/*
 * We map the EFI regions needed for runtime services non-contiguously,
 * with preserved alignment on virtual addresses starting from -4G down
 * for a total max space of 64G. This way, we provide for stable runtime
 * services addresses across kernels so that a kexec'd kernel can still
 * use them.
 *
 * This is the main reason why we're doing stable VA mappings for RT
 * services.
 *
 * This flag is used in conjuction with a chicken bit called
 * "efi=old_map" which can be used as a fallback to the old runtime
 * services mapping method in case there's some b0rkage with a
 * particular EFI implementation (haha, it is hard to hold up the
 * sarcasm here...).
 */
#define EFI_OLD_MEMMAP          EFI_ARCH_1

#define EFI32_LOADER_SIGNATURE  "EL32"
#define EFI64_LOADER_SIGNATURE  "EL64"

#ifdef CONFIG_X86_32


extern unsigned long asmlinkage efi_call_phys(void *, ...);

/*
 * Wrap all the virtual calls in a way that forces the parameters on the stack.
 */

/* Use this macro if your virtual returns a non-void value */
#define efi_call_virt(f, args...) \
({                                                                      \
        efi_status_t __s;                                               \
        kernel_fpu_begin();                                             \
        __s = ((efi_##f##_t __attribute__((regparm(0)))*)               \
                efi.systab->runtime->f)(args);                          \
        kernel_fpu_end();                                               \
        __s;                                                            \
})

/* Use this macro if your virtual call does not return any value */
#define __efi_call_virt(f, args...) \
({                                                                      \
        kernel_fpu_begin();                                             \
        ((efi_##f##_t __attribute__((regparm(0)))*)                     \
                efi.systab->runtime->f)(args);                          \
        kernel_fpu_end();                                               \
})

#define efi_ioremap(addr, size, type, attr)     ioremap_cache(addr, size)

#else /* !CONFIG_X86_32 */

#define EFI_LOADER_SIGNATURE    "EL64"

extern u64 asmlinkage efi_call(void *fp, ...);

#define efi_call_phys(f, args...)               efi_call((f), args)

#define efi_call_virt(f, ...)                                           \
({                                                                      \
        efi_status_t __s;                                               \
                                                                        \
        efi_sync_low_kernel_mappings();                                 \
        preempt_disable();                                              \
        __kernel_fpu_begin();                                           \
        __s = efi_call((void *)efi.systab->runtime->f, __VA_ARGS__);    \
        __kernel_fpu_end();                                             \
        preempt_enable();                                               \
        __s;                                                            \
})

/*
 * All X86_64 virt calls return non-void values. Thus, use non-void call for
 * virt calls that would be void on X86_32.
 */
#define __efi_call_virt(f, args...) efi_call_virt(f, args)

extern void __iomem *__init efi_ioremap(unsigned long addr, unsigned long size,
                                        u32 type, u64 attribute);

#endif /* CONFIG_X86_32 */

extern struct efi_scratch efi_scratch;
extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable);
extern int __init efi_memblock_x86_reserve_range(void);
extern void __init efi_call_phys_prolog(void);
extern void __init efi_call_phys_epilog(void);
extern void __init efi_unmap_memmap(void);
extern void __init efi_memory_uc(u64 addr, unsigned long size);
extern void __init efi_map_region(efi_memory_desc_t *md);
extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
extern void efi_sync_low_kernel_mappings(void);
extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
extern void __init efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages);
extern void __init old_map_region(efi_memory_desc_t *md);
extern void __init runtime_code_page_mkexec(void);
extern void __init efi_runtime_mkexec(void);
extern void __init efi_dump_pagetable(void);
extern void __init efi_apply_memmap_quirks(void);
extern int __init efi_reuse_config(u64 tables, int nr_tables);
extern void efi_delete_dummy_variable(void);

struct efi_setup_data {
        u64 fw_vendor;
        u64 runtime;
        u64 tables;
        u64 smbios;
        u64 reserved[8];
};

extern u64 efi_setup;

#ifdef CONFIG_EFI

static inline bool efi_is_native(void)
{
        return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
}

static inline bool efi_runtime_supported(void)
{
        if (efi_is_native())
                return true;

        if (IS_ENABLED(CONFIG_EFI_MIXED) && !efi_enabled(EFI_OLD_MEMMAP))
                return true;

        return false;
}

extern struct console early_efi_console;
extern void parse_efi_setup(u64 phys_addr, u32 data_len);

#ifdef CONFIG_EFI_MIXED
extern void efi_thunk_runtime_setup(void);
extern efi_status_t efi_thunk_set_virtual_address_map(
        void *phys_set_virtual_address_map,
        unsigned long memory_map_size,
        unsigned long descriptor_size,
        u32 descriptor_version,
        efi_memory_desc_t *virtual_map);
#else
static inline void efi_thunk_runtime_setup(void) {}
static inline efi_status_t efi_thunk_set_virtual_address_map(
        void *phys_set_virtual_address_map,
        unsigned long memory_map_size,
        unsigned long descriptor_size,
        u32 descriptor_version,
        efi_memory_desc_t *virtual_map)
{
        return EFI_SUCCESS;
}
#endif /* CONFIG_EFI_MIXED */

extern bool efi_reboot_required(void);

#else
static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
static inline bool efi_reboot_required(void)
{
        return false;
}
#endif /* CONFIG_EFI */

#endif /* _ASM_X86_EFI_H */