Ok I am going to copy some examples.

2008/8/18, Benjamin Herrenschmidt <benh@kernel.crashing.org>:
On Mon, 2008-08-18 at 10:45 +0200, Sébastien Chrétien wrote:
> Hello,
>
> I am developping a Linux for my PPC Board. I must write a
> define_machine structure (marchdep_calls). Where can I find some
> Information about functions of this structure ?


It isn't well documented unfortunately. Best is to look at what others
do... and then find your way through.

I agree somebody should write dome doco one day ... in the meantime,
feel free to ask questions here.

Cheers,
Ben.