drivers/firmware/efi/libstub/efistub.h

#ifndef _DRIVERS_FIRMWARE_EFI_EFISTUB_H
#define _DRIVERS_FIRMWARE_EFI_EFISTUB_H

/* error code which can't be mistaken for valid address */
#define EFI_ERROR	(~0UL)

/*
 * __init annotations should not be used in the EFI stub, since the code is
 * either included in the decompressor (x86, ARM) where they have no effect,
 * or the whole stub is __init annotated at the section level (arm64), by
 * renaming the sections, in which case the __init annotation will be
 * redundant, and will result in section names like .init.init.text, and our
 * linker script does not expect that.
 */
#undef __init

/*
 * Allow the platform to override the allocation granularity: this allows
 * systems that have the capability to run with a larger page size to deal
 * with the allocations for initrd and fdt more efficiently.
 */
#ifndef EFI_ALLOC_ALIGN
#define EFI_ALLOC_ALIGN		EFI_PAGE_SIZE
#endif

void efi_char16_printk(efi_system_table_t *, efi_char16_t *);

efi_status_t efi_open_volume(efi_system_table_t *sys_table_arg, void *__image,
			     void **__fh);

unsigned long get_dram_base(efi_system_table_t *sys_table_arg);

efi_status_t allocate_new_fdt_and_exit_boot(efi_system_table_t *sys_table,
					    void *handle,
					    unsigned long *new_fdt_addr,
					    unsigned long max_addr,
					    u64 initrd_addr, u64 initrd_size,
					    char *cmdline_ptr,
					    unsigned long fdt_addr,
					    unsigned long fdt_size);

void *get_fdt(efi_system_table_t *sys_table, unsigned long *fdt_size);

void efi_get_virtmap(efi_memory_desc_t *memory_map, unsigned long map_size,
		     unsigned long desc_size, efi_memory_desc_t *runtime_map,
		     int *count);

efi_status_t efi_get_random_bytes(efi_system_table_t *sys_table,
				  unsigned long size, u8 *out);

efi_status_t efi_random_alloc(efi_system_table_t *sys_table_arg,
			      unsigned long size, unsigned long align,
			      unsigned long *addr, unsigned long random_seed);

efi_status_t check_platform_features(efi_system_table_t *sys_table_arg);

efi_status_t efi_random_get_seed(efi_system_table_t *sys_table_arg);

#endif