scripts/image_signing/set_gbb_flags.sh

   1 #!/bin/sh
   2 #
   3 # Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
   4 # Use of this source code is governed by a BSD-style license that can be
   5 # found in the LICENSE file.
   6 #
   7 # This script can change GBB flags in system live firmware or a given image
   8 # file.
   9
  10 SCRIPT_BASE="$(dirname "$0")"
  11 . "$SCRIPT_BASE/common_minimal.sh"
  12 load_shflags || exit 1
  13
  14 # DEFINE_string name default_value description flag
  15 DEFINE_string file "" "Path to firmware image. Default to system firmware." "f"
  16 DEFINE_boolean check_wp $FLAGS_TRUE "Check write protection states first." ""
  17
  18 # Globals
  19 # ----------------------------------------------------------------------------
  20 set -e
  21
  22 # Values from vboot_reference/firmware/include/gbb_header.h
  23 GBBFLAGS_DESCRIPTION="
  24   Defined flags (some values may be not supported by all systems):
  25
  26   GBB_FLAG_DEV_SCREEN_SHORT_DELAY            0x00000001
  27   GBB_FLAG_LOAD_OPTION_ROMS                  0x00000002
  28   GBB_FLAG_ENABLE_ALTERNATE_OS               0x00000004
  29   GBB_FLAG_FORCE_DEV_SWITCH_ON               0x00000008
  30   GBB_FLAG_FORCE_DEV_BOOT_USB                0x00000010
  31   GBB_FLAG_DISABLE_FW_ROLLBACK_CHECK         0x00000020
  32   GBB_FLAG_ENTER_TRIGGERS_TONORM             0x00000040
  33   GBB_FLAG_FORCE_DEV_BOOT_LEGACY             0x00000080
  34   GBB_FLAG_FAFT_KEY_OVERIDE                  0x00000100
  35   GBB_FLAG_DISABLE_EC_SOFTWARE_SYNC          0x00000200
  36   GBB_FLAG_DEFAULT_DEV_BOOT_LEGACY           0x00000400
  37   GBB_FLAG_DISABLE_PD_SOFTWARE_SYNC          0x00000800
  38   GBB_FLAG_DISABLE_LID_SHUTDOWN              0x00001000
  39   GBB_FLAG_FORCE_DEV_BOOT_FASTBOOT_FULL_CAP  0x00002000
  40   GBB_FLAG_ENABLE_SERIAL                     0x00004000
  41
  42   To get a developer-friendly device, try 0x11 (short_delay + boot_usb).
  43   For factory-related tests (always DEV), try 0x39.
  44   For early development (disable EC/PD software sync), try 0xa39.
  45 "
  46
  47 FLAGS_HELP="Changes ChromeOS Firmware GBB Flags value.
  48
  49   Usage: $0 [option_flags] GBB_FLAGS_VALUE
  50   $GBBFLAGS_DESCRIPTION"
  51
  52 FLASHROM_COMMON_OPT="-p host"
  53 FLASHROM_READ_OPT="$FLASHROM_COMMON_OPT -i GBB -r"
  54 FLASHROM_WRITE_OPT="$FLASHROM_COMMON_OPT -i GBB --fast-verify -w"
  55
  56 # Check write protection
  57 # ----------------------------------------------------------------------------
  58 check_write_protection() {
  59   local hw_wp="" sw_wp=""
  60   if ! crossystem "wpsw_boot?0"; then
  61     hw_wp="on"
  62   fi
  63   local wp_states="$(flashrom --wp-status 2>/dev/null | grep WP)"
  64   local wp_disabled="$(echo "$wp_states" | grep "WP:.*is disabled.")"
  65   local wp_zero_len="$(echo "$wp_states" | grep "WP:.*, len=0x00000000")"
  66   if [ -z "$wp_disabled" -a -z "$wp_zero_len" ]; then
  67     sw_wp="on"
  68   fi
  69   if [ -n "$hw_wp" -a -n "$sw_wp" ]; then
  70     return $FLAGS_FALSE
  71   fi
  72   return $FLAGS_TRUE
  73 }
  74
  75 # Main
  76 # ----------------------------------------------------------------------------
  77 main() {
  78   if [ "$#" != "1" ]; then
  79     flags_help
  80     exit 1
  81   fi
  82
  83   local value="$(($1))"
  84   local image_file="$FLAGS_file"
  85
  86   if [ -z "$FLAGS_file" ]; then
  87     image_file="$(make_temp_file)"
  88     flashrom $FLASHROM_READ_OPT "$image_file"
  89   fi
  90
  91   # Process file
  92   local old_value="$(gbb_utility -g --flags "$image_file")"
  93   printf "Setting GBB flags from %s to 0x%x.." "$old_value" "$value" >&2
  94   gbb_utility -s --flags="$value" "$image_file"
  95
  96   if [ -z "$FLAGS_file" ]; then
  97     if [ "$FLAGS_check_wp" = "$FLAGS_TRUE" ]; then
  98       if ! check_write_protection; then
  99         echo ""
 100         echo "WARNING: System GBB Flags are NOT changed!!!"
 101         echo "ERROR: You must disable write protection before setting flags."
 102         exit 1
 103       fi
 104     fi
 105     flashrom $FLASHROM_WRITE_OPT "$image_file"
 106   fi
 107 }
 108
 109 # Parse command line
 110 FLAGS "$@" || exit 1
 111 ORIGINAL_PARAMS="$@"
 112 eval set -- "$FLAGS_ARGV"
 113
 114 main "$@"