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 <linux/libfdt.h>
  14 #include <asm/sections.h>
  15
  16 /*
  17  * AArch64 requires the DTB to be 8-byte aligned in the first 512MiB from
  18  * start of kernel and may not cross a 2MiB boundary. We set alignment to
  19  * 2MiB so we know it won't cross a 2MiB boundary.
  20  */
  21 #define EFI_FDT_ALIGN   SZ_2M   /* used by allocate_new_fdt_and_exit_boot() */
  22 #define MAX_FDT_OFFSET  SZ_512M
  23
  24 #define efi_call_early(f, ...) sys_table_arg->boottime->f(__VA_ARGS__)
  25
  26 static void efi_char16_printk(efi_system_table_t *sys_table_arg,
  27                               efi_char16_t *str);
  28
  29 static efi_status_t efi_open_volume(efi_system_table_t *sys_table,
  30                                     void *__image, void **__fh);
  31 static efi_status_t efi_file_close(void *handle);
  32
  33 static efi_status_t
  34 efi_file_read(void *handle, unsigned long *size, void *addr);
  35
  36 static efi_status_t
  37 efi_file_size(efi_system_table_t *sys_table, void *__fh,
  38               efi_char16_t *filename_16, void **handle, u64 *file_sz);
  39
  40 /* Include shared EFI stub code */
  41 #include "../../../drivers/firmware/efi/efi-stub-helper.c"
  42 #include "../../../drivers/firmware/efi/fdt.c"
  43 #include "../../../drivers/firmware/efi/arm-stub.c"
  44
  45
  46 static efi_status_t handle_kernel_image(efi_system_table_t *sys_table,
  47                                         unsigned long *image_addr,
  48                                         unsigned long *image_size,
  49                                         unsigned long *reserve_addr,
  50                                         unsigned long *reserve_size,
  51                                         unsigned long dram_base,
  52                                         efi_loaded_image_t *image)
  53 {
  54         efi_status_t status;
  55         unsigned long kernel_size, kernel_memsize = 0;
  56
  57         /* Relocate the image, if required. */
  58         kernel_size = _edata - _text;
  59         if (*image_addr != (dram_base + TEXT_OFFSET)) {
  60                 kernel_memsize = kernel_size + (_end - _edata);
  61                 status = efi_relocate_kernel(sys_table, image_addr,
  62                                              kernel_size, kernel_memsize,
  63                                              dram_base + TEXT_OFFSET,
  64                                              PAGE_SIZE);
  65                 if (status != EFI_SUCCESS) {
  66                         pr_efi_err(sys_table, "Failed to relocate kernel\n");
  67                         return status;
  68                 }
  69                 if (*image_addr != (dram_base + TEXT_OFFSET)) {
  70                         pr_efi_err(sys_table, "Failed to alloc kernel memory\n");
  71                         efi_free(sys_table, kernel_memsize, *image_addr);
  72                         return EFI_ERROR;
  73                 }
  74                 *image_size = kernel_memsize;
  75         }
  76
  77
  78         return EFI_SUCCESS;
  79 }