> if only the cache coherence wouldn't have been a show stopper for Linux.

Actually, it was cache *non*-coherency ;-)

> Today I think an e300/400MHZ core isn't enough, not even for low end. The
> Efika 5200B is just able to decode a TV stream - but only with a low bitrate.

The MPC5121e that was supposed to go into the "Efika 2" includes the Auxiliary eXecution Engine (AXE), which was "designed for efficient implementation of audio and other algorithms key to multimedia and telematics systems" (Freescale quote). But I don't know how much that unit could be of real help with A/V stream decoding. Moreover, I don't even know if that unit was ever put to any real use by anybody outside Freescale.