[Openchrome-users] which VIA chipset for custom STB?

[Xavier Bachelot]

Patrik Kluba wrote:
> Hi All!
> 
> I'm about to build a dedicated linux-based STB, preferably a fanless,
> low-power one. Mainly this is the reason I have stuck with VIA
> chipsets (as AMD chipsets have no good linux support, Nvidia ones are
> power hungry and maybe too powerful for a STB, and low-power
> Intel-based systems don't appear be powerful enough, but if you can
> recommend me something, don't hesistate to write me), but after
> running through the list archives and being subscribed to the lists,
> still don't know which one to choose from them.
> My only requirement is working MPEG-2 acceleration support, and
> optionally MPEG-4 (DVB card will be a HVR3000, FlyDVB Trio or a
> HVR4000 not necessarily using its DVB/S2 capability until HW
> acceleration is working).
> I know that recent chipsets are not supported completely or at all by
> the openchrome driver currently. As long as this is the case, I can
> stick with a closed source driver *if* that one can be considered as
> stable. By the way, my job is to sketch embedded systems for my
> company, validate schematics created by our affiliates, write device
> drivers for the components, and getting life into the prototypes, so I
> have experience in driver writing and willing to contribute to the
> project.
> Now I'm oscillating between a CX700M-based Jetway J7F5-VHE (sporting a
> 1.0-1.2 GHz C7 or Eden processor) and a VX800-based Jetway NF76
> (sporting a 1.0 GHz Via Nano processor).
> Thanks for any advices.
> 
The only XvMC acceleration level implemented currently is VLD, but this
is the most CPU hungry part of MPEG2 decoding. Nothing related to MPEG4
is implemented yet.
However, XvMC requires a working DRM module, so this excludes everything
Chrome9 based (K8M890, P4M900, VX800). This will have to wait for the
Chrome9 DRM module to enter kernel/drm tree. See links below.
CX700 XvMC is currently not working as well, because CX700 uses a new,
and slightly different MPEG engine, but the VLD part should be pretty
similar. afaiu, It shouldn't be too much work to get it going for VLD at
least, but it will require both the hardware, time and knowledge.

Other chipsets might be better supported wrt XvMC. Not all of them are
HD capable though, only CN400 is iirc.

http://article.gmane.org/gmane.comp.video.dri.devel/32970
http://article.gmane.org/gmane.comp.video.dri.devel/32973
http://article.gmane.org/gmane.comp.video.dri.devel/32976
http://article.gmane.org/gmane.comp.video.dri.devel/32978

Regards,
Xavier