Re: PCI bridging broken?

From: Simon Trimmer (
Date: Tue Aug 01 2000 - 14:29:49 EST

On Mon, 31 Jul 2000, Martin Mares wrote:
> Hello!
> > I looked back through the archives and noticed this had been raised before,
> > but the problem is certainly not fixed in the 2.4 testX kernels.
> >
> > Where 2.2 kernels work fine, v2.4 kernels won't find any devices when
> > scanning behind DECchip 21150 PCI bridges. In more detail, the initial
> > pci_read_config_dword() in pci_scan_device() returns 0xffffffff (the case
> > when a slot is empty).
> >
> > I have experimented with the different kernel pci options, off and conf2 list
> > the devices but the messages sent to the log don't inspire confidence in the
> > system stability.
> >
> > These bridges are quite common, my test example is a dell latitude notebook
> > which uses the bridge to handle the docking station. I contacted a few of the
> > people originally involved who basically gave up and went back to 2.2
> > kernels.
> I'll take a look at it.
> Can you send me 'lspci -vvx' output for both 2.2 and 2.4 kernels?

Hi Martin,

find attached three files, lspci -vvx for the two kernels (2.2.16 and
2.4.test5 pre1) and the .config file for the 2.4 kernel. I didn't use any pci
boot options for those ones and I included the config for the broken kernel
just in case I missed an option for something.

I'd really like to get this working so I can go back to using 2.4 from day to
day, are there any other tests I can try out?


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
Please read the FAQ at

This archive was generated by hypermail 2b29 : Mon Aug 07 2000 - 21:00:06 EST