Re: [Patch v2] Make PCI extended config space (MMCONFIG) a driveropt-in

[Benjamin Herrenschmidt]

On Thu, 2007-12-27 at 21:37 -0800, Linus Torvalds wrote:
> 
> On Fri, 28 Dec 2007, Benjamin Herrenschmidt wrote:
> > 
> > I have embedded boards where proper CRS operations is critical since the
> > kernel brings the PCIe link up itself, and thus is likely to hit devices
> > still in the middle of CRS.
> 
> .. but that's perfectly fine. A PCI-E bridge will certainly retry it in 
> hardware (or it isn't a PCI-E bridge!).

Only a handful of times in many bridges I've seen.
 
> So I'm going to disable that thing. If there is some _other_ PCI-E bridge 
> that is simply buggy, and cannot handle the hw retry itself or is just 
> otherwise dodgy, we can have a white-list for cases where it really needs 
> to be done, but the current code is just bogus.

If you disable it, then isn't there also a problem with PCIE->PCI-X
bridge which will stop issuing CRS when they should ? (not sure here, I
may be a bit confused).

Ben.


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