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

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2013, 2014 Linaro Ltd;  <[email protected]>
   4  *
   5  * This file implements the EFI boot stub for the arm64 kernel.
   6  * Adapted from ARM version by Mark Salter <[email protected]>
   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         unsigned long kernel_size, kernel_codesize, kernel_memsize;
  25
  26         if (image->image_base != _text) {
  27                 efi_err("FIRMWARE BUG: efi_loaded_image_t::image_base has bogus value\n");
  28                 image->image_base = _text;
  29         }
  30
  31         if (!IS_ALIGNED((u64)_text, SEGMENT_ALIGN))
  32                 efi_err("FIRMWARE BUG: kernel image not aligned on %dk boundary\n",
  33                         SEGMENT_ALIGN >> 10);
  34
  35         kernel_size = _edata - _text;
  36         kernel_codesize = __inittext_end - _text;
  37         kernel_memsize = kernel_size + (_end - _edata);
  38         *reserve_size = kernel_memsize;
  39         *image_addr = (unsigned long)_text;
  40
  41         return efi_kaslr_relocate_kernel(image_addr, reserve_addr, reserve_size,
  42                                          kernel_size, kernel_codesize, kernel_memsize,
  43                                          efi_kaslr_get_phys_seed(image_handle));
  44 }
  45
  46 asmlinkage void primary_entry(void);
  47
  48 unsigned long primary_entry_offset(void)
  49 {
  50         /*
  51          * When built as part of the kernel, the EFI stub cannot branch to the
  52          * kernel proper via the image header, as the PE/COFF header is
  53          * strictly not part of the in-memory presentation of the image, only
  54          * of the file representation. So instead, we need to jump to the
  55          * actual entrypoint in the .text region of the image.
  56          */
  57         return (char *)primary_entry - _text;
  58 }
  59
  60 void efi_icache_sync(unsigned long start, unsigned long end)
  61 {
  62         caches_clean_inval_pou(start, end);
  63 }