Re: [patches] [patch 3/5] x86: Add PCI extended config space access for AMD Barcelona

Robert Richter
2007-09-05T10:36:12Z

On 05.09.07 11:12:00, H. Peter Anvin wrote:
> >PCI Devices will not be the same on the bus since PCI read/write
> >functions will have different behavior. Without the patches you will
> >get an error when accessing ECS with CF8. We need ECS access for
> >patches that setups local interrupt vectors. This patches will be
> >released soon.
>
> You're missing the point. How will the PCI bus transactions be
> different when using MMCONFIG versus your extended CF8 version?

Misunderstood you, with this patch there will be the same behavior,
that's the intention. There might be slightly differences in ordering
rules for read/write cycles. IO config cycles are serialized while
ordering rules for MMIO config cycles may result in unexpected
behavior for PCI devices on the bus.

-Robert

--
Advanced Micro Devices, Inc.
Operating System Research Center
email: robert.richter@amd.com