arch/arm64/kernel/efi-stub.c

   1 /*
   2  * Copyright (C) 2013, 2014 Linaro Ltd;  <roy.franz@linaro.org>
   3  *
   4  * This file implements the EFI boot stub for the arm64 kernel.
   5  * Adapted from ARM version by Mark Salter <msalter@redhat.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  */
  12 #include <linux/efi.h>
  13 #include <asm/efi.h>
  14 #include <asm/sections.h>
  15
  16 efi_status_t __init handle_kernel_image(efi_system_table_t *sys_table,
  17                                         unsigned long *image_addr,
  18                                         unsigned long *image_size,
  19                                         unsigned long *reserve_addr,
  20                                         unsigned long *reserve_size,
  21                                         unsigned long dram_base,
  22                                         efi_loaded_image_t *image)
  23 {
  24         efi_status_t status;
  25         unsigned long kernel_size, kernel_memsize = 0;
  26
  27         /* Relocate the image, if required. */
  28         kernel_size = _edata - _text;
  29         if (*image_addr != (dram_base + TEXT_OFFSET)) {
  30                 kernel_memsize = kernel_size + (_end - _edata);
  31                 status = efi_low_alloc(sys_table, kernel_memsize + TEXT_OFFSET,
  32                                        SZ_2M, reserve_addr);
  33                 if (status != EFI_SUCCESS) {
  34                         pr_efi_err(sys_table, "Failed to relocate kernel\n");
  35                         return status;
  36                 }
  37                 memcpy((void *)*reserve_addr + TEXT_OFFSET, (void *)*image_addr,
  38                        kernel_size);
  39                 *image_addr = *reserve_addr + TEXT_OFFSET;
  40                 *reserve_size = kernel_memsize + TEXT_OFFSET;
  41         }
  42
  43
  44         return EFI_SUCCESS;
  45 }