To build drivers and tools from GIT we first need to enter a maintenance chroot of the diskless system in question.

If git has not been installed yet through the package list facility of the diskless scripts, you have to install it now

yum install git

As root change to /root via

cd ~

and check out the white rabbit source tree:

git clone --recursive -b asterisk https://github.com/stefanrauch/bel_projects.git

Enter source tree

cd bel_projects

and build programs and driver modules via:

make KERNELVER=3.6.11.9-rt42 etherbone tools eca tlu driver

Specifying the exact kernel version string with KERNELVER is crucial. Here, KERNELVER=3.6.11.9-rt42 just serves as an example.
To list available valid kernel versions installed on the FEC, do

ls -l /boot/vmlinuz-* | sed -nre 's@.*vmlinuz-(.*).*@\1@p'