update_kernel: first cut at arm support

remote_access.sh

 # Copyright (c) 2009 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.
 
 # Library for setting up remote access and running remote commands.
 
 DEFAULT_PRIVATE_KEY="${GCLIENT_ROOT}/src/scripts/mod_for_test_scripts/\
 ssh_keys/testing_rsa"
 
 DEFINE_string remote "" "remote hostname/IP of running Chromium OS instance"
@@ skipping 65 matching lines @@
   local timeout=$2
   local -r TIMEOUT_INC=1
   local current_timeout=0
   while is_pid_running ${pid} && [ ${current_timeout} -lt ${timeout} ]; do
     sleep ${TIMEOUT_INC}
     current_timeout=$((current_timeout + TIMEOUT_INC))
   done
   ! is_pid_running ${pid}
 }
 
+function learn_arch() {
+  [ -n "${FLAGS_arch}" ] && return
+  remote_sh uname -m
+  FLAGS_arch=$(echo "${REMOTE_OUT}" | sed s/armv7l/arm/g)
+  if [ -z "${FLAGS_arch}" ]; then
+    error "Arch required"
+    exit 1
+  fi
+  info "Target reports arch is ${FLAGS_arch}"
+}
+
 # Checks to see if a machine has rebooted using the presence of a tmp file.
 function check_if_rebooted() {
   local output_file="${TMP}/output"
   while true; do
     REMOTE_OUT=""
     # This may fail while the machine is down so generate output and a
     # boolean result to distinguish between down/timeout and real failure
     ! remote_sh_allow_changed_host_key \
         "echo 0; [ -e /tmp/awaiting_reboot ] && echo '1'; true"
     echo "${REMOTE_OUT}" > "${output_file}"
@@ skipping 28 matching lines @@
 
 function remote_access_init() {
   TMP_PRIVATE_KEY=$TMP/private_key
   TMP_KNOWN_HOSTS=$TMP/known_hosts
   if [ -z "$FLAGS_remote" ]; then
     echo "Please specify --remote=<IP-or-hostname> of the Chromium OS instance"
     exit 1
   fi
   set_up_remote_access
 }