host/cros_sign_bootstub

#!/bin/bash

# Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

# This utility uses cbootimage to signs a bootstub so that the Tegra boot ROM
# will load and run it.

# Include common CrOS utilities.
. "/usr/lib/crosutils/common.sh"

# Command line options
DEFINE_string bct "" "DDR memory timing BCT file."
DEFINE_string flash "" "Boot flash parameter file."
DEFINE_string bootstub "" "Bootstub firmware image to sign."
DEFINE_string output "bootstub.bin" "Signed bootstub + BCT output file."
DEFINE_string text_base "0xe08000" "Load address and entry point for bootstub."
DEFINE_string config "" "Directory for temporary configuration files."

# Parse command line.
FLAGS "$@" || exit 1
eval set -- "${FLAGS_ARGV}"

# Die on errors.
set -e

CROS_LOG_PREFIX="cros_sign_bootstub"

function construct_config() {
  local flash_file="$1"
  local bct_file="$2"
  local bootstub="$3"
  local text_base="$4"

  #
  # The cbootimage config file format is not yet documented.  Below is
  # a minimal config file that merges a BCT file and bootloader; in
  # this case our stub U-Boot image.  We do not use the Version, but it
  # needs to be set.
  #
  # Currently a bug in cbootimage prevents us from setting Redundancy to
  # 0.  Redundancy controls how many instances of the BCT should be
  # written to the signed image.  A value of 1 causes two instances to
  # be written.
  #
  # The BootLoader parameter specifies the bootloader image to use.  It
  # also specifies the load address for the bootloader in RAM and the
  # entry point of the resulting image.  For U-Boot these are the same
  # value (TEXT_BASE).
  #
  echo "Bctfile    = ${bct_file};"
  echo "Version    = 1;"
  echo "Redundancy = 1;"

  # TODO(robotboy): This needs to be added back in to support selecting the
  # boot flash device.  With this commented out we can only boot from the
  # boot device that the source BCT file was created for.  This is commented
  # out because it causes the resulting image to not boot if it is added.
  # TRACKER: http://code.google.com/p/chromium-os/issues/detail?id=12712
  #
  # echo ""
  # cat ${flash_file}
  # echo ""

  echo "BootLoader = ${bootstub},${text_base},${text_base},Complete;"
}

###############################################################################

check_for_file "boot flash device config" "..." "${FLAGS_flash}"
check_for_file "BCT" "........................" "${FLAGS_bct}"
check_for_file "bootstub image" "............." "${FLAGS_bootstub}"

check_for_tool "cbootimage" "cbootimage"

if [ -z "${FLAGS_config}" ]; then
  config=$(mktemp -d)

  trap "rm -rf ${config}" EXIT
else
  mkdir -p "${FLAGS_config}"

  config=${FLAGS_config}
fi

construct_config \
  "${FLAGS_flash}" \
  "${FLAGS_bct}" \
  "${FLAGS_bootstub}" \
  "${FLAGS_text_base}" > "${config}/boot.cfg"

cbootimage "${config}/boot.cfg" "${FLAGS_output}"