Re: VIA text console corruption and fix.

Berend De Schouwer (
28 Mar 2002 11:33:21 +0200

On Thu, 2002-03-28 at 00:55, Steven Walter wrote:
> On Wed, Mar 27, 2002 at 09:17:30PM +0200, Berend De Schouwer wrote:
> [...]
> > I have 3000+ identical VIA KT133/Duron 750MHz machines. In 20% of these
> > the bug is visible, in the others, it isn't. The machines run in an
> > LTSP-ish configuration. The machines are supposed to be identical (they
> > were bought together), but have different revisions of BIOS versions,
> > etc. They have on-board S3 Savage cards that steal RAM from the main
> > RAM.
> Aha, another. You're the fourth or fifth person with this problem. I
> have a patch very similar to yours. What my patch does is only clear
> bit 7, which is what was experimentally determined to disable the Write
> Memory Queue. So far it seems that only KM133 (KT133 w/onboard S3
> Savage) are afflicted.

Well, these boards use KL133s (not KM133s). The KL133 also has an
integrated S3 ProSavage card.

Maybe another bit seems to need setting somewhere. But where?

> However, the patch isn't being accepted until an explanation from VIA is
> obtained (apparently the head kernel honcho's were explicitly told to
> clear bit 5). I'm working on that now.

I've been told the same. Clearing bit 5 is apparently necessary to
prevent IDE crruption. Asus lists two motherboards, one with a KL133,
one with a KL133A. It looks like the motherboards using KL133s are
broken, and the KL133As work.

How bad is "not clearing bit 5"?
How bad is

if ((device_id = kl133) || (device_id = km133)) {
/* Don't clear bit 5 */

Is it possible to clear bit 5, but not bit X, to fix it?

> --
> -Steven
> In a time of universal deceit, telling the truth is a revolutionary act.
> -- George Orwell
> He's alive. He's alive! Oh, that fellow at RadioShack said I was mad!
> Well, who's mad now?
> -- Montgomery C. Burns

Berend De Schouwer

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