I have added a BSP for TWR-MPC5125 to Openembedded.
A tutorial, which describes
how to install it on a Gentoo Linux host,
how to build the Linux kernel and several root file systems (e.g. OPIE, GPE, Xfce) and
how to run it on the target can
be found at: http://en.gentoo-wiki.com/wiki/Freescale_TWR-MPC5125/Openembedded
When a monitor, a mouse and a keyboard are connected to the board,
three different GUIs
GPE http://gpe.linuxtogo.org/ or
can be tested and used.
The Linux kernel is based on the source code of the Linux kernel 2.6.29-v2010041601
for the TWR-MPC5125-KIT in TWRMPC5125LinuxBSP.rar
There is still some work to do, but I hope it is a good starting point.