linux_kernel/arch/arm64/kernel/efi-stub.c

/*
 * Copyright (C) 2013, 2014 Linaro Ltd;  <roy.franz@linaro.org>
 *
 * This file implements the EFI boot stub for the arm64 kernel.
 * Adapted from ARM version by Mark Salter <msalter@redhat.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */
#include <linux/efi.h>
#include <asm/efi.h>
#include <asm/sections.h>

efi_status_t __init handle_kernel_image(efi_system_table_t *sys_table,
					unsigned long *image_addr,
					unsigned long *image_size,
					unsigned long *reserve_addr,
					unsigned long *reserve_size,
					unsigned long dram_base,
					efi_loaded_image_t *image)
{
	efi_status_t status;
	unsigned long kernel_size, kernel_memsize = 0;

	/* Relocate the image, if required. */
	kernel_size = _edata - _text;
	if (*image_addr != (dram_base + TEXT_OFFSET)) {
		kernel_memsize = kernel_size + (_end - _edata);
		status = efi_low_alloc(sys_table, kernel_memsize + TEXT_OFFSET,
				       SZ_2M, reserve_addr);
		if (status != EFI_SUCCESS) {
			pr_efi_err(sys_table, "Failed to relocate kernel\n");
			return status;
		}
		memcpy((void *)*reserve_addr + TEXT_OFFSET, (void *)*image_addr,
		       kernel_size);
		*image_addr = *reserve_addr + TEXT_OFFSET;
		*reserve_size = kernel_memsize + TEXT_OFFSET;
	}


	return EFI_SUCCESS;
}