Re: [PATCH v4 0/8] perf: arm: Make PMUv3 driver available for aarch32

Will Deacon
2023-03-24T18:06:04Z

On Fri, Mar 24, 2023 at 01:56:42PM +0000, Mark Rutland wrote:
> On Sat, Mar 18, 2023 at 10:02:33AM +0000, Marc Zyngier wrote:
> > On Fri, 17 Mar 2023 19:50:19 +0000,
> > Zaid Al-Bassam <zalbassam@google.com> wrote:
> > >
> > > Currently, PMUv3 driver is only available for ARMv8 aarch64 platforms,
> > > ARMv8 platorms running in aarch32 mode dont have access to the driver.
> > > This is, especially, a problem for ARMv8 platforms that only have
> > > aarch32 support, like the Cortex-A32.
> > >
> > > Make the PMUv3 driver available to arm arch (ARMv8 aarch32) by moving
> > > the PMUv3 driver from arm64 to drivers, that makes the driver common
> > > to both arm and arm64 architectures, then add PMUv3 arm Support.
> > >
> > > The main work in this patchset was made a while back by Marc Zyngier
> > > in [1]. Patchset version 1 [v1] rebases Marc's patches to the latest
> > > kernel revision and adds additional patches to accommodate the changes
> > > in the kernel since Marc wrote the patches.
> > >
> > > version 2 [v2] of the patchset was created by Marc Zyngier and I
> > > picked it up from [2].
> >
> > The SoB chain is now a bit off as you picked it from my tree. Nothing
> > that we can't fix, but please be careful in the future. You also
> > failed to pick Florian's Tested-by: tags, which is worse. Please make
> > sure to pick these things as people reply to your series.
> >
> > Will, Mark: any objection to the general shape of this series? I've
> > been using it again to test the 32bit PMU support in KVM, and would
> > rather see something merged while the architecture still has some
> > relevance.
>
> I think the general shape looks fine, but this is going to conflict with
> Anshuman's BRBE series, so we'll need to figure out how to stage these w.r.t.
> one another.
>
> Will, any preference between handling the merge manually or rebasing one atop
> the other? We'll presumably want to place the BRBE files under drivers/perf/ if
> we've moved the PMUv3 code there.

Probably easiest to queue this and have Anshuman rebase BRBE on top once
I've done that. I'll look at it next week.

Will