I was just told about it by zivan56, and my mi4 page was just updated: the SanDisk Sansa View uses the mi4 file format and it is clearly PortalPlayer based. mi4code can find the crypto key, so decrypting it for disassembly is easy.
In fact, the zip contains two mi4 files and the second one is called “mediaproc.mi4″ seems to be for a separate processor or similar, and it makes sense since the PP can’t do the movie playback etc with the specs that they boast for this player.
That media processor might very well be a “nv6110“, referred to many times in the firmware image.
Go crazy in the Rockbox forum thread about it!