[Xenomai] Xenomai FlexCAN driver - where to start?

[Tomasz Guszkowski <tomasz.guszkowski@pwr.wroc.pl>]

Hello!

I am to write a MPC8309 (powerpc made by Freescale) FlexCAN driver for Xenomai. I have a working non-RT driver for this machine. Xenomai 2.6.0 works flawlessly as far I can assess it.

I have started converting a non-RT version of the driver to rtdm (rtcan) API and after some time spent on it I have an impression it will last a good while. (I am new to Xenomai driver development.)

I have also analyzed mscan and sja1000 drivers and the conclusion is that RT and non-RT versions have almost no common parts, at least meld can't easily point them.

So the questions are:

What is the preferrable starting point for writing Xenomai CAN driver? 
Is my path (non-RT driver -> rtdm/rtcan driver) optimal? 
Does there exist a better way, for example a kind of a "template" for filling up with some HW-specific code?
Now I think about trying to use a crippled mscan version as a template, despite the fact that mscan and FlexCAN have no common parts besides using Flattened Device Tree for HW description.Is this a good idea?

Any hints are welcomed.

--
Tomek