src/lib/boot_device.c

   1 /*
   2  * This file is part of the coreboot project.
   3  *
   4  * Copyright 2015 Google Inc.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; version 2 of the License.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #include <boot_device.h>
  17
  18 void __attribute__((weak)) boot_device_init(void)
  19 {
  20         /* Provide weak do-nothing init. */
  21 }
  22
  23 static int boot_device_subregion(const struct region *sub,
  24                                 struct region_device *subrd,
  25                                 const struct region_device *parent)
  26 {
  27         if (parent == NULL)
  28                 return -1;
  29
  30         return rdev_chain(subrd, parent, region_offset(sub), region_sz(sub));
  31 }
  32
  33 int boot_device_ro_subregion(const struct region *sub,
  34                                 struct region_device *subrd)
  35 {
  36         /* Ensure boot device has been initialized at least once. */
  37         boot_device_init();
  38
  39         return boot_device_subregion(sub, subrd, boot_device_ro());
  40 }
  41
  42 int boot_device_rw_subregion(const struct region *sub,
  43                                 struct region_device *subrd)
  44 {
  45         /* Ensure boot device has been initialized at least once. */
  46         boot_device_init();
  47
  48         return boot_device_subregion(sub, subrd, boot_device_rw());
  49 }