diff --git a/install_toolchain b/install_toolchain
new file mode 100755
index 0000000000..3ba0235462
--- /dev/null
+++ b/install_toolchain
@@ -0,0 +1,192 @@
+#!/bin/bash
+
+# Copyright (c) 2012 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.
+
+. "$(dirname "$0")/common.sh" || exit 1
+. "${SRC_ROOT}/platform/dev/toolchain_utils.sh" || exit 1
+
+# Script must run inside the chroot
+restart_in_chroot_if_needed "$@"
+
+assert_not_root_user
+
+# Developer-visible flags.
+DEFINE_string board "$DEFAULT_BOARD" \
+  "The name of the board to set up."
+DEFINE_string board_root "" \
+  "Path of the board root to install into.  Defaults to /build/<board>."
+DEFINE_boolean configure $FLAGS_TRUE \
+  "Update config files in <board_root>/etc after installation."
+DEFINE_boolean force $FLAGS_FALSE \
+  "Install toolchain even if already up to date."
+DEFINE_string toolchain "" \
+  "Toolchain.  For example: i686-pc-linux-gnu, armv7a-softfloat-linux-gnueabi"
+
+
+FLAGS_HELP="usage: $(basename $0) [flags]
+
+Installs cross toolchain libraries into a board_root.  This script is not
+meant to be used by developers directly.  Run at your own risk.
+"
+
+show_help_if_requested "$@"
+
+# Parse command line flags
+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 'switch_to_strict_mode' is specified before now.
+switch_to_strict_mode
+
+# Get the version number of a toolchain package.
+cross_get_version() {
+  local pkg=$1
+  local toolchain=${2:-${FLAGS_toolchain}}
+  local cpv
+  if [[ "$CHOST" != "${toolchain}" ]]; then
+    if [[  "$pkg" = "gcc" ]]; then
+      # Users can install multiple versions of gcc at once, so we need to call
+      # gcc-config to find out which installed version is selected.
+      local path=$(CTARGET="${toolchain}" gcc-config -B || true)
+      cpv=$(portageq owners / "$path" | sed -e '/^\t/d')
+    else
+      cpv=$(portageq match / "cross-${toolchain}/${pkg}" || true)
+    fi
+  else
+    if [[ "$pkg" = glibc ]] ; then
+      cpv=$(portageq match / sys-libs/glibc || true)
+    elif [[ "$pkg" = gcc ]] ; then
+      cpv=$(portageq match / sys-devel/gcc || true)
+    else
+      die "Unknown pkg ${pkg}"
+    fi
+  fi
+  local cp=$(echo $cpv | sed -e 's/-r[0-9]*$//; s/-[^-]*$//')
+  local result="${cpv#$cp-}"
+  local count="$(echo $result | wc -w)"
+  if [ "$count" -gt "1" ]; then
+    die "Multiple versions of $pkg installed"
+  elif [ "$count" -lt "1" ]; then
+    die "Cannot find $pkg"
+  fi
+  echo $result
+}
+
+# Checks whether the libc version installed in the board
+# matches the one installed by the toolchain.
+board_needs_libc_update() {
+  if [[ ! -e "${BOARD_SETUP}" ]]; then
+    return 0
+  fi
+
+  local board_version=$(. "${BOARD_SETUP}"; echo "${LIBC_VERSION}")
+  local toolchain_version=$(cross_get_version glibc)
+  if [[ "${board_version}" = "${toolchain_version}" ]]; then
+    return 1
+  fi
+  return 0
+}
+
+install_toolchain_in_provided() {
+  local gcc_ver="$1"
+  local glibc_ver="$2"
+  # Tell portage that toolchain packages are already installed in the sysroot.
+  sudo_clobber "$BOARD_PROFILE/package.provided" << EOF
+sys-devel/gcc-$gcc_ver
+sys-libs/glibc-$glibc_ver
+EOF
+}
+
+# Install all of the stuff that depends on the toolchain versions
+# into the board root.
+install_toolchain_in_board() {
+  local cmds
+  local gcc_ver=$(cross_get_version gcc)
+  local libc_ver=$(cross_get_version glibc)
+  if [[ -z ${gcc_ver} || -z ${libc_ver} ]]; then
+    die "Cannot find toolchain to install into board root"
+  fi
+  echo "Installing the toolchain into the board root."
+  # Untar glibc to get most of the headers required to build.
+  local libc_tar="glibc-${libc_ver}.tbz2"
+
+  # Install libc libraries.
+  if [ "${CHOST}" != "$FLAGS_toolchain" ] ; then
+    local libc_path="${PKGDIR}/cross-${FLAGS_toolchain}/${libc_tar}"
+    cmds=(
+      "tar jxpf '${libc_path}' -C '${BOARD_ROOT}' \
+          './usr/${FLAGS_toolchain}' --strip-components=3"
+      "mkdir -p '${BOARD_ROOT}/usr/lib/debug'"
+      "tar jxpf '${libc_path}' -C '${BOARD_ROOT}/usr/lib/debug' \
+          './usr/lib/debug/usr/${FLAGS_toolchain}' --strip-components=6 \
+          || warn 'libc debug info not copied.'"
+    )
+    # TODO(asharif): Remove this hack after a while.
+    local board_gcc_dir="${BOARD_ROOT}/usr/lib/gcc"
+    if [[ -L "${board_gcc_dir}" ]] ; then
+      cmd+=("rm -f '${board_gcc_dir}'")
+    fi
+    sudo_multi "${cmds[@]}"
+    copy_gcc_libs "${BOARD_ROOT}" "cross-$FLAGS_toolchain/gcc-$gcc_ver"
+  else
+    cmds=(
+      "mkdir -p '${BOARD_ROOT}'{/usr,}/lib64 '${BOARD_ROOT}/usr/lib/debug'"
+      "ln -sfT '${BOARD_ROOT}/usr/lib64' '${BOARD_ROOT}/usr/lib'"
+      "ln -sfT '${BOARD_ROOT}/lib64' '${BOARD_ROOT}/lib'"
+      "emerge --oneshot --nodeps -k --root='${BOARD_ROOT}' \
+          =sys-libs/glibc-${libc_ver}"
+    )
+    sudo_multi "${cmds[@]}"
+  fi
+
+  # Some header files are needed also for rpcbind (NFS support)
+  # TODO: Figure out a better way of doing this too?
+  cmds=(
+    "cp -a /usr/include/rpcsvc/mount.h '${BOARD_ROOT}/usr/include/rpcsvc'"
+    "cp -a /usr/include/rpcsvc/rquota.h '${BOARD_ROOT}/usr/include/rpcsvc'"
+    "cp -a /usr/include/rpcsvc/nfs_prot.h '${BOARD_ROOT}/usr/include/rpcsvc'"
+    "cp -a /usr/include/rpcsvc/yppasswd.h '${BOARD_ROOT}/usr/include/rpcsvc'"
+  )
+  sudo_multi "${cmds[@]}"
+
+  if [[ ${FLAGS_configure} -eq ${FLAGS_TRUE} ]]; then
+    install_toolchain_in_provided "$gcc_ver" "$libc_ver"
+
+    # Configure new libc version in make.conf.board_setup.
+    sudo sed -i -e "/^LIBC_VERSION=/d" "$BOARD_SETUP"
+    echo "LIBC_VERSION=\"$libc_ver\"" | sudo_append "$BOARD_SETUP"
+  fi
+}
+
+set -u
+
+if [ -z "$FLAGS_board" ] ; then
+  die "--board required."
+fi
+
+get_board_and_variant $FLAGS_board ""
+
+BOARD_ROOT="${FLAGS_board_root:-/build/${BOARD_VARIANT}}"
+BOARD_ETC="${BOARD_ROOT}/etc"
+BOARD_SETUP="${BOARD_ETC}/make.conf.board_setup"
+BOARD_PROFILE="${BOARD_ETC}/portage/profile"
+
+all_toolchains=( $(get_all_board_toolchains "${BOARD}") )
+: ${FLAGS_toolchain:=${all_toolchains[0]}}
+
+if [ -z "${FLAGS_toolchain}" ]; then
+  die "No toolchain specified in board overlay or on command line."
+fi
+
+eval "$(portageq envvar -v CHOST PKGDIR)"
+
+if [[ ${FLAGS_force} -eq ${FLAGS_TRUE} ]] || \
+    board_needs_libc_update; then
+  info "Updating libc in the board."
+  install_toolchain_in_board
+else
+  info "Cross toolchain already up to date.  Nothing to do."
+fi
diff --git a/setup_board b/setup_board
index f27738a3d4..eb48d94312 100755
--- a/setup_board
+++ b/setup_board
@@ -147,116 +147,8 @@ EOF
   sudo_multi "${cmds[@]}"
 }
 
-# Checks whether the libc version installed in the board
-# matches the one installed by the toolchain.
-board_needs_libc_update() {
-  local board_version=$(. "${BOARD_SETUP}"; echo "${LIBC_VERSION}")
-  local toolchain_version=$(cross_get_version glibc)
-  if [[ "${board_version}" = "${toolchain_version}" ]]; then
-    return 1
-  fi
-  return 0
-}
-
-# Get the version number of a toolchain package.
-cross_get_version() {
-  local pkg="$1"
-  local toolchain="${2:-${FLAGS_toolchain}}"
-  local cpv=""
-  if [[ "$CHOST" != "${toolchain}" ]]; then
-    if [[  "$pkg" = "gcc" ]]; then
-      # Users can install multiple versions of gcc at once, so we need to call
-      # gcc-config to find out which installed version is selected.
-      local path=$(CTARGET=${toolchain} gcc-config -B || true)
-      cpv=$(portageq owners / $path | sed -e '/^\t/d')
-    else
-      cpv=$(portageq match / cross-${toolchain}/${pkg} || true)
-    fi
-  else
-    if [[ "$pkg" = glibc ]] ; then
-      cpv=$(portageq match / sys-libs/glibc || true)
-    elif [[ "$pkg" = gcc ]] ; then
-      cpv=$(portageq match / sys-devel/gcc || true)
-    else
-      die "Unknown pkg ${pkg}"
-    fi
-  fi
-  local cp=$(echo $cpv | sed -e 's/-r[0-9]*$//; s/-[^-]*$//')
-  local result="${cpv#$cp-}"
-  local count="$(echo $result | wc -w)"
-  if [ "$count" -gt "1" ]; then
-    die "Multiple versions of $pkg installed"
-  elif [ "$count" -lt "1" ]; then
-    die "Cannot find $pkg"
-  fi
-  echo $result
-}
-
-install_toolchain_in_provided() {
-  local gcc_ver="$1"
-  local glibc_ver="$2"
-  # Tell portage that toolchain packages are already installed in the sysroot.
-  (
-    echo sys-devel/gcc-$gcc_ver
-    echo sys-libs/glibc-$glibc_ver
-  ) | sudo_clobber "$BOARD_PROFILE/package.provided"
-}
-
-# Install all of the stuff that depends on the toolchain versions
-# into the board root.
-install_toolchain_in_board() {
-  local cmds
-  local gcc_ver=$(cross_get_version gcc)
-  local libc_ver=$(cross_get_version glibc)
-  if [[ -z ${gcc_ver} || -z ${libc_ver} ]]; then
-    die "Cannot find toolchain to install into board root"
-  fi
-  echo "Installing the toolchain into the board root."
-  # Untar glibc to get most of the headers required to build.
-  LIBC_TAR="glibc-${libc_ver}.tbz2"
-
-  # Install libc libraries.
-  if [ "${CHOST}" != "$FLAGS_toolchain" ] ; then
-    LIBC_PATH="${PKGDIR}/cross-${FLAGS_toolchain}/${LIBC_TAR}"
-    sudo tar jxpf "${LIBC_PATH}" -C "${BOARD_ROOT}" ./usr/${FLAGS_toolchain} --strip-components=3
-    sudo mkdir -p ${BOARD_ROOT}/usr/lib/debug
-    sudo tar jxpf "${LIBC_PATH}" -C "${BOARD_ROOT}/usr/lib/debug" ./usr/lib/debug/usr/${FLAGS_toolchain} --strip-components=6 || warn "libc debug info not copied."
-    GCC_PKG=cross-${FLAGS_toolchain}/gcc-$gcc_ver
-
-    # TODO(asharif): Remove this hack after a while.
-    BOARD_GCC_DIR="${BOARD_ROOT}/usr/lib/gcc"
-    if [[ -L "${BOARD_GCC_DIR}" ]] ; then
-      sudo rm -f "${BOARD_GCC_DIR}"
-    fi
-    copy_gcc_libs "${BOARD_ROOT}" "cross-$FLAGS_toolchain/gcc-$gcc_ver"
-  else
-    cmds=(
-      "mkdir -p '${BOARD_ROOT}'{/usr,}/lib64 '${BOARD_ROOT}/usr/lib/debug'"
-      "ln -sfT '${BOARD_ROOT}/usr/lib64' '${BOARD_ROOT}/usr/lib'"
-      "ln -sfT '${BOARD_ROOT}/lib64' '${BOARD_ROOT}/lib'"
-    )
-    sudo_multi "${cmds[@]}"
-    LIBC_PATH="${PKGDIR}/sys-libs/${LIBC_TAR}"
-    sudo emerge --oneshot --nodeps -k --root=${BOARD_ROOT} =sys-libs/glibc-${libc_ver}
-    # TODO: we have no debug
-    GCC_PKG=sys-devel/gcc-$gcc_ver
-  fi
-
-  # Some header files are needed also for rpcbind (NFS support)
-  # TODO: Figure out a better way of doing this too?
-  cmds=(
-    "cp -a /usr/include/rpcsvc/mount.h '${BOARD_ROOT}/usr/include/rpcsvc'"
-    "cp -a /usr/include/rpcsvc/rquota.h '${BOARD_ROOT}/usr/include/rpcsvc'"
-    "cp -a /usr/include/rpcsvc/nfs_prot.h '${BOARD_ROOT}/usr/include/rpcsvc'"
-    "cp -a /usr/include/rpcsvc/yppasswd.h '${BOARD_ROOT}/usr/include/rpcsvc'"
-  )
-  sudo_multi "${cmds[@]}"
-
-  install_toolchain_in_provided "$gcc_ver" "$libc_ver"
-
-  # Configure new libc version in make.conf.board_setup.
-  sudo sed -i -e "/^LIBC_VERSION=/d" $BOARD_SETUP
-  echo "LIBC_VERSION=\"$libc_ver\"" | sudo_append $BOARD_SETUP
+install_toolchain() {
+  "${GCLIENT_ROOT}/src/scripts/install_toolchain" --board="${BOARD_VARIANT}"
 }
 
 # Print contents of $BOARD_ETC/make.conf.board. This file sources make.conf
@@ -456,11 +348,8 @@ if [ -d "${BOARD_ROOT}" ]; then
       warn "Not setting up board root. "
       warn "Use --force to clobber the board root and start again."
     fi
-    if board_needs_libc_update; then
-      # Update the users libc in their board if needed.
-      echo "Updating libc in the board."
-      install_toolchain_in_board
-    fi
+    # Update the users libc in their board if needed.
+    install_toolchain
     exit 0
   fi
 else
@@ -519,7 +408,7 @@ if ! ${HOST_BOARD}; then
   # We install the toolchain related bits after the BOARD_ROOT, BOARD_PROFILE
   # and BOARD_ETC directories have been created.
   if [[ ${FLAGS_regen_configs} -eq ${FLAGS_FALSE} ]]; then
-    install_toolchain_in_board
+    install_toolchain
   fi
 fi
 # Setup make.globals and the profile.