Re: Video scrolling (was: SMALL bug)

Chris Evans (chris@ferret.lmh.ox.ac.uk)
Sat, 26 Oct 1996 12:47:15 +0100 (BST)


On Sat, 26 Oct 1996, Alan Modra wrote:

> No real problem. The kernel just happened to be updating some of the
> 16bit VGA registers right when that part of the screen was being
> refreshed. For compatibility with old hardware, the register update
> is done with 8 bit IOs, (with pauses too). You can do 16bit IO on
> nearly all hardware, which greatly reduces occurence of the 'flashing'
>
> Here's a patch I made quite a while ago.

[snip]

It seems to me that there are many such patches floating around, of the
type "improve performance/features but only work on 90%+ of hardware".
Obviously, we must keep the case where things work on ~100% of harware,
including old and broken stuff.

It would be nice, however, perhaps at the start of a make config, to be
able to say "all my hardware is relatively new and standard", so that
many people can pick up these enhancements.

Chris.