Re: PCI cache line messages 2.4/2.5

Alan Cox (alan@lxorguk.ukuu.org.uk)
05 Jun 2003 11:39:15 +0100


On Mer, 2003-06-04 at 23:39, Jeff Garzik wrote:
> > PCI: 00:1d.7 PCI cache line size set incorrectly (0 bytes) by BIOS/FW.
> > PCI: 00:1d.7 PCI cache line size corrected to 128.
> >
> > This is the onboard USB EHCI (Intel D845 PESV).
> > lspci below.
> >
> > What's going on ?
>
>
> Pretty much exactly what the message says :)
>
> Your BIOS did not set the PCI cache line size correctly. The kernel
> caught that mistake, and fixed it.

I can't find anywhere the BIOS is obliged to set it for you if a PnP OS
is installed, ditto in the presence of any form of hotplug the test is
wrong.

As far as I can see you can only warn if MWI is already set in the
control word, and (I'd have to check the spec) possibly if the
cache line size is non zero.

(simple hotplug thought experiment to prove the point

Soft boot a thinkpad 600
As the bios transfers to grub insert in docking station

explain how the bios sets the cache line size..)

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/