Re: [PATCH v7 3/3] arm64: Add architecture support for PCI

Benjamin Herrenschmidt
2014-03-16T06:23:38Z

On Fri, 2014-03-14 at 20:10 +0100, Arnd Bergmann wrote:
> > As for the other two functions, I've no special attachment to where they are present
> > and I'm happy to move them into drivers/pci on the condition that the patchset doesn't
> > double in size. The reason why I'm weary of touching other architectures in a significant
> > way is the current lack of engineering bandwidth and way of testing all the architectures.
> > My low friction approach has been to introduce them in arm64 and then slowly move them
> > into core (and yes, I know about good intentions and the road to hell.)
>
> I think everyone working on PCI is fed up with having arch-specific implementations
> of all these, and Bjorn has been very supportive of generic infrastructure in the
> past. Even just adding a generic infrastructure in a common place that is used
> only by one architecture in my mind would be a significant improvement.

I agree, it's a reasonable approach and microblaze which is simple and just "copied"
powerpc originally would be a good one to move over as well.

powerpc itself has many historical quirks and while I'm interested in a common
implementation, it will take me a bit of spare time to get through things and
figure out what can be done there and what "hooks" might still be necessary.

At this point, it's mostly a matter of:

- I'm the one who knows the most about the powerpc PCI code as I wrote large
chunks of it

- I'm very very very busy with some other things at the moment

So don't take my silence on these matters as a lack of interest, I think it's
definitely all going in the right direction, I just don't have much bandwidth
to consider the move of powerpc over just yet.

Cheers,
Ben.