So far I've managed to get couple of interesting things happen in QEMU: 1280 pixels wide screen, which is normal 80x25 text mode but with each pixel twice as wide, and mm.. completely black screen.. that's the most promising thing.
I think I'm setting all the sequencer stuff, all CRTCs (copied from xorg then manually doublechecked for the best of my ability), the misc register, attributes 0x10,0x12,0x13,0x14 then graphics 5,6,7,8...
I'm also reprogramming my palette (and that works even without the mode switching) then clearing the screen (at 0xa0000) with white, so mm.. I should be getting something other than black.
Any suggestions where the problem might be?
[edit] Duh, also ment to say that if somebody has a straightforward listing of port-accesses for setting a given mode, please gimme...
