u-boot important url

u-boot source code site:

git clone git://git.denx.de/u-boot.git
git clone https://git.toradex.com/u-boot-toradex.git
git clone git://git.jdl.com/software/dtc.git
git clone git://git.kernel.org/pub/scm/utils/dtc/dtc.git
git clone git://git.buildroot.net/buildroot

u-boot document: