update_kernel: first cut at arm support

update_kernel.sh

 #!/bin/bash
 
 # Copyright (c) 2009-2010 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.
 
 # Script to update the kernel on a live running ChromiumOS instance.
 
 # Load common constants.  This should be the first executable line.
 # The path to common.sh should be relative to your script's location.
 
 . "$(dirname $0)/common.sh"
 . "$(dirname $0)/remote_access.sh"
 
 # Script must be run inside the chroot.
 restart_in_chroot_if_needed $*
 
 DEFINE_string board "" "Override board reported by target"
+DEFINE_string device "" "Override boot device reported by target"
 DEFINE_string partition "" "Override kernel partition reported by target"
+DEFINE_string arch "" "Override architecture reported by target"
 DEFINE_boolean modules false "Update modules on target"
 DEFINE_boolean firmware false "Update firmware on target"
 
 # Parse command line.
 FLAGS "$@" || exit 1
 eval set -- "${FLAGS_ARGV}"
 
 # Only now can we die on error.  shflags functions leak non-zero error codes,
 # so will die prematurely if 'set -e' is specified before now.
 set -e
 
 function cleanup {
   cleanup_remote_access
   rm -rf "${TMP}"
 }
 
+function learn_device() {
+  [ -n "${FLAGS_device}" ] && return
+  remote_sh df /mnt/stateful_partition
+  FLAGS_device=$(echo "${REMOTE_OUT}" | awk '/dev/ {print $1}' | sed s/1\$//)
+  info "Target reports root device is ${FLAGS_device}"
+}
+
 # Ask the target what the kernel partition is
 function learn_partition() {
   [ -n "${FLAGS_partition}" ] && return
   remote_sh cat /proc/cmdline
-  if echo "${REMOTE_OUT}" | grep -q "/dev/sda3"; then
-    FLAGS_partition="/dev/sda2"
+  if echo "${REMOTE_OUT}" | egrep -q "${FLAGS_device}3"; then
+    FLAGS_partition="${FLAGS_device}2"
   else
-    FLAGS_partition="/dev/sda4"
+    FLAGS_partition="${FLAGS_device}4"
   fi
   if [ -z "${FLAGS_partition}" ]; then
     error "Partition required"
     exit 1
   fi
   info "Target reports kernel partition is ${FLAGS_partition}"
 }
 
+function make_kernelimage() {
+
+  if [[ "${FLAGS_arch}" == "arm" ]]; then
+    ./build_kernel_image.sh --arch=arm \
+    --root='/dev/${devname}${rootpart}' \
+    --vmlinuz=/build/${FLAGS_board}/boot/vmlinux.uimg --to new_kern.bin
+  else
+    vbutil_kernel --pack new_kern.bin \
+    --keyblock /usr/share/vboot/devkeys/kernel.keyblock \
+    --signprivate /usr/share/vboot/devkeys/kernel_data_key.vbprivk \
+    --version 1 \
+    --config ../build/images/${FLAGS_board}/latest/config.txt \
+    --bootloader /lib64/bootstub/bootstub.efi \
+    --vmlinuz /build/${FLAGS_board}/boot/vmlinuz
+  fi
+}
+
 function main() {
   trap cleanup EXIT
 
   TMP=$(mktemp -d /tmp/image_to_live.XXXX)
 
   remote_access_init
 
+  learn_arch
+
   learn_board
 
+  learn_device 
+
+  learn_partition
+
   remote_sh uname -r -v
 
   old_kernel="${REMOTE_OUT}"
 
-  vbutil_kernel --pack new_kern.bin \
-    --keyblock /usr/share/vboot/devkeys/kernel.keyblock \
-    --signprivate /usr/share/vboot/devkeys/kernel_data_key.vbprivk \
-    --version 1 \
-    --config ../build/images/"${FLAGS_board}"/latest/config.txt \
-    --bootloader /lib64/bootstub/bootstub.efi \
-    --vmlinuz /build/"${FLAGS_board}"/boot/vmlinuz
-
-  learn_partition
+  make_kernelimage
 
   remote_cp_to new_kern.bin /tmp
 
   remote_sh dd if=/tmp/new_kern.bin of="${FLAGS_partition}"
 
   if [[ ${FLAGS_modules} -eq ${FLAGS_TRUE} ]]; then
     echo "copying modules"
-    tar -C /build/"${FLAGS_board}"/lib/modules -cjf new_modules.tar .
+    tar -C /build/"${FLAGS_board}"/lib/modules -cjf /tmp/new_modules.tar .
 
-    remote_cp_to new_modules.tar /tmp/
+    remote_cp_to /tmp/new_modules.tar /tmp/
 
     remote_sh mount -o remount,rw /
     remote_sh tar -C /lib/modules -xjf /tmp/new_modules.tar
   fi
 
   if [[ ${FLAGS_firmware} -eq ${FLAGS_TRUE} ]]; then
     echo "copying firmware"
-    tar -C /build/"${FLAGS_board}"/lib/firmware -cjf new_firmware.tar .
+    tar -C /build/"${FLAGS_board}"/lib/firmware -cjf /tmp/new_firmware.tar .
 
-    remote_cp_to new_firmware.tar /tmp/
+    remote_cp_to /tmp/new_firmware.tar /tmp/
 
     remote_sh mount -o remount,rw /
     remote_sh tar -C /lib/firmware -xjf /tmp/new_firmware.tar
   fi
 
   remote_reboot
 
   remote_sh uname -r -v
   info "old kernel: ${old_kernel}"
   info "new kernel: ${REMOTE_OUT}"
 }
 
-main $@
+main "$@"