diff --git a/.gitmodules b/.gitmodules
index b666686..70e157a 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -4,3 +4,6 @@
 [submodule "src/koreader"]
 	path = src/koreader
 	url = git@github.com:lgeek/koreader.git
+[submodule "src/u-boot"]
+	path = src/u-boot
+	url = git@github.com:lgeek/u-boot-okreader.git
diff --git a/build.sh b/build.sh
index 5ae32d7..f86f069 100755
--- a/build.sh
+++ b/build.sh
@@ -23,7 +23,7 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 # SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-available_targets=("linux-image" "linux-modules" "firmware-okreader" "koreader")
+available_targets=("u-boot" "linux-image" "linux-modules" "firmware-okreader" "koreader")
 
 print_usage() {
   echo "Usage: build.sh [TARGET]"
@@ -67,6 +67,13 @@ parse_args() {
   done
 }
 
+compile_uboot() {
+  cd src/u-boot
+  make mx50_rdp_config
+  make -j$(($(nproc)+1))
+  cd ../../
+}
+
 compile_linux_image() {
   cd src/linux
   make mx50_kobo_defconfig
@@ -142,6 +149,9 @@ parse_args $@
 
 for target in ${targets[*]}; do
   case $target in
+    u-boot)
+      compile_uboot
+      ;;
     linux-image)
       compile_linux_image
       ;;
diff --git a/src/u-boot b/src/u-boot
new file mode 160000
index 0000000..8892136
--- /dev/null
+++ b/src/u-boot
@@ -0,0 +1 @@
+Subproject commit 8892136c43903b00ec9f77a599db139254cd1f51