Subject: Re: UltraDMA problems under 1.6F (probably hardware)
To: Frank van der Linden <email@example.com>
From: Richard Earnshaw <firstname.lastname@example.org>
Date: 08/16/2002 11:50:31
> > On Wed, Aug 14, 2002 at 07:25:14AM -0400, gabriel rosenkoetter wrote:
> > > Hrm. That's three different controllers, counting mine (Acer Labs
> > > M5229 rev. 0xc4). Well, unless your Asus motherobard has a Via IDE
> > The Acer controller always produces these errors on the first few
> > accesses (at least, it does under NetBSD, I don't know about other
> > OSs). It has done so ~forever.
> > In my mail/NAT machine, I have:
> > pciide0 at pci0 dev 15 function 0: Acer Labs M5229 UDMA IDE Controller (rev. 0xc
> > 1)
> > That gives me one error and a downgrade message after boot, and after that
> > it remains perfectly happy, so I've never investigated this.
> I've seen this on the Cats board as well. Not sure precisely which chip
> but it is an Acer Labs one doing UDMA/33.
So I messed around with this last night (it is a M5229 BTW). Changing
drvp->n_dmaerrs = NERRS_MAX-1;
in ata.c to
drvp->n_dmaerrs = NERRS_MAX-2;
And my disk runs quite happily in UDMA-2 mode.