$ git clone https://github.com/hardkernel/u-boot.git -b odroidc2-v2015.01
$ git clone https://github.com/hardkernel/u-boot_firmware.git -b odroidc2-bl301

$ cd u-boot

$ git remote add u-boot_firmware ../u-boot_firmware/
$ git fetch u-boot_firmware 
$ git merge --no-commit u-boot_firmware/odroidc2-bl301