Re: Seagate SATA 3GB/s drive connected to via vt8251 using ahci module

[Aalderd Bouwman <boac@wanadoo.nl>]

Maybe it is an idea to disable NCQ for vt8251 compile-time (kernel-option) 
until it works correctly?

On Tuesday 20 June 2006 21:31, Bastiaan Jacques wrote:
> On Tuesday 20 June 2006 17:37, Tejun Heo wrote:
> > [CC'ing Bastiaan Jacques. Hi!]
>
> Hey!
>
> > Do you happen to have a different drive which can do NCQ?
> > Preferably, one from another vendor?
>
> I've just tried it with a Maxtor drive supporting NCQ, and it didn't
> work.
>
> > AFAICS, the ahci driver is
> > doing NCQ as the AHCI spec specifies and all ICH controllers seem to
> > be quite happy with it.  I wanna know whether the problem is from the
> > specific combination of the controller and the drive or the via
> > controller needs a different programming sequence for NCQ in general.
>
> It would seem the problem is in the VIA controller. Surprise, surprise.
>
> > Bastiaan, do you know whether we need to do things differently to use
> > NCQ on vt8251?
>
> Apparently we have a hardware or firmware bug to work around, but I have
> no idea what we should be doing differently.