drivers/firmware/efi/libstub/arm64-stub.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2013, 2014 Linaro Ltd;  <roy.franz@linaro.org>
   4  *
   5  * This file implements the EFI boot stub for the arm64 kernel.
   6  * Adapted from ARM version by Mark Salter <msalter@redhat.com>
   7  */
   8
   9
  10 #include <linux/efi.h>
  11 #include <asm/efi.h>
  12 #include <asm/memory.h>
  13 #include <asm/sections.h>
  14
  15 #include "efistub.h"
  16
  17 efi_status_t handle_kernel_image(unsigned long *image_addr,
  18                                  unsigned long *image_size,
  19                                  unsigned long *reserve_addr,
  20                                  unsigned long *reserve_size,
  21                                  efi_loaded_image_t *image,
  22                                  efi_handle_t image_handle)
  23 {
  24         efi_status_t status;
  25         unsigned long kernel_size, kernel_codesize, kernel_memsize;
  26
  27         if (image->image_base != _text) {
  28                 efi_err("FIRMWARE BUG: efi_loaded_image_t::image_base has bogus value\n");
  29                 image->image_base = _text;
  30         }
  31
  32         if (!IS_ALIGNED((u64)_text, SEGMENT_ALIGN))
  33                 efi_err("FIRMWARE BUG: kernel image not aligned on %dk boundary\n",
  34                         SEGMENT_ALIGN >> 10);
  35
  36         kernel_size = _edata - _text;
  37         kernel_codesize = __inittext_end - _text;
  38         kernel_memsize = kernel_size + (_end - _edata);
  39         *reserve_size = kernel_memsize;
  40         *image_addr = (unsigned long)_text;
  41
  42         status = efi_kaslr_relocate_kernel(image_addr,
  43                                            reserve_addr, reserve_size,
  44                                            kernel_size, kernel_codesize,
  45                                            kernel_memsize,
  46                                            efi_kaslr_get_phys_seed(image_handle));
  47         if (status != EFI_SUCCESS)
  48                 return status;
  49
  50         return EFI_SUCCESS;
  51 }
  52
  53 asmlinkage void primary_entry(void);
  54
  55 unsigned long primary_entry_offset(void)
  56 {
  57         /*
  58          * When built as part of the kernel, the EFI stub cannot branch to the
  59          * kernel proper via the image header, as the PE/COFF header is
  60          * strictly not part of the in-memory presentation of the image, only
  61          * of the file representation. So instead, we need to jump to the
  62          * actual entrypoint in the .text region of the image.
  63          */
  64         return (char *)primary_entry - _text;
  65 }
  66
  67 void efi_icache_sync(unsigned long start, unsigned long end)
  68 {
  69         caches_clean_inval_pou(start, end);
  70 }