Re: Screen corruption in 2.4.18

[Andre Pang <ozone@algorithm.com.au>]

On Sat, Mar 23, 2002 at 10:06:47AM -0600, Steven Walter wrote:

> > Don't get it wrong. I *do have* an VT8365. VT8365 (ProSavage KM133) is 
> > somewhat the same as VT8363 (KT133), except that 8365 has an integrated 
> > Savage graphics card (which *I use*).
> 
> Aha... I see.  And in thinking about it, I realize that my motherboard
> also has this integrated graphics card.  Perhaps this is the difference?
> Unfortunately, it seems they both report the same PCI id, so I don't
> really know of a way to differentiate them.

I can verify Danijel's report -- I have the same setup
(VT8363+VT8353, a.k.a. ProSavage KM133), and I experience the
same screen corruption.  Clearing only bit 7 of register 55 fixes
the problem; clearing bits 5 and 6 causes the video to go all
borky.  There's been another thread about it on lkml over the
last week or so.

> I looked at that datasheet, and the datasheet for the 8363.  Both said
> not to program offset 55, and both said the bits we are clearing are
> "reserved."  Perhaps we should contact VIA directly, tell them the
> problem we're having with their current fix, tell them our theory, and
> ask if we're right.

Heh, a VIA contact who knows what the hell that register does
would be nice :).

In the meantime, I'd probably suggest a patch which looks for
clears only bit 7 of Rx55 if an 8363 and an 8365 is found.  I'll
whip one up later today.


-- 
#ozone/algorithm <ozone@algorithm.com.au>          - trust.in.love.to.save