adaptec 2940

[David Hogan dhog@lore.plan9.cs.su.oz.au]

> it's a funny old world - this morning i awoke to mail from ngr asking if
> i had any adaptec docs, he felt compelled to write a driver. and yesterday i
> finished a first pass on the virge chip for aux/vga (it's just a trio64 more
> or less, there's a little twiddling to get the cursor working above 1024x768;
> the /vx chip will require a little more fiddling but i don't have one of
> those to try. in fact, if you are prepared to do without the hardware cursor
> above 1024x768 you can just give the ctlr entry in /lib/vgadb for your card
> as 'trio64' and it should work).

Indeed, that's exactly what I've been doing!  (I guessed that the card was
trio64-compatible...).  I'm kind of interested in the advanced features
of the card, such as bus-mastering DMA, and scaling video data...  This
card is good; even without using the DMA, the screen updates  are fast.
I've been running inferno in an 8-1/2 window without noticing any slowdown
from the crummy old graphics model :-)  Of course, having a fast processor
helps!  (150MHz P6).