anholt 1095443edb Fix aperture size detection on some ALi chipsets by only using the lowest 4 bits
to check aperture size, avoiding hangs.  Maintain the rest of the bits when
setting/unsetting ATTBASE.  This essentially matches Linux's AGP driver as well.

PR:		kern/70037
Submitted by:	Mark Tinguely <tinguely at casselton dot net>
Obtained from:	NetBSD
2004-08-21 06:24:21 +00:00
..
2004-08-05 13:01:29 +00:00