Support for PowerPC e200 cores

[Ralf Corsepius]

On Fri, 2008-02-15 at 10:47 +0100, Sebastian Huber wrote:
> Hi,
> we want to develop a BSP for a MPC5566 evaluation board. It uses a e200
> processor core. My first job is to get the basic tools ready. I am quite
> new in
> this business, so please have mercy with me if I ask to many clumsy
> questions ;-)
> 
> According to the "Freescale PowerPC Architecture Primer" (page 12) the e200
> core is code-compatible with an e500 core. The e500 core is supported by
> gcc.
> You need to configure the binutils and gcc with the
> "--target=powerpc-elf --with-cpu=8540"
> options. I have not yet tested this with the standard sources.
> 
> I want to build the RTEMS 4.8 RPMs for an openSuSE 10.3 host so that they
> support this cpu type. I haven't figured out how to do it with some wiki
> research. Can someone give me any hints where to start?
Before anything else, you should seriously ask yourself if you
absolutely need a specialized variant for this CPU, or if using a
"slightly suboptimal" instruction set wouldn't be sufficient.


If the answer is no, you're done wrt. gcc and could use the rpms we ship
(suse10.3 rpms are available) and chose the multilib variant you decided
to be sufficiently compatible.

If the answer is yes, the simplest way to proceed would be to add the
variant you want as a multilib variant to the rtems-gcc sources (In your
case: gcc/config/rs6000/t-rtems). 
In parallel, you would have to extend rtems/cpukit/score/cpu/powerpc to
acknowledge this new multilib variant.


Alternatively to all this, you could try to build a customized
toolchain, specially tailored for your target. In this case, you will
want to consult binutils and GCC's fine manuals.


Ralf