Rock2/Android/develop
Development
Please refer Rock/Android_Build#Initializing_a_Build_Environment to set up the building environment if you haven't set it already.
Get the source code
Download here radxa_rock2_square_android4.4.2_sdk_20150324.tgz
Build u-boot
cd u-boot make rk3288_defconfig make -j4
Build the kernel
cd kernel make radxa_rock2_square_defconfig make radxa-rock2-square.img -j 16
Build android source code
source build/envsetup.sh lunch 12 make -j 8
Generate the image
./mkimage.sh ota
you will get boot.img recovery.img system.img under rockdev/Image, and update.img ( e.g. rock2_android_kitkat_15-03-23_141904.img)under rockdev