[GIT PULL] ARM: SoC/genpd driver updates for v6.6

[Ulf Hansson]

On Mon, 11 Sept 2023 at 09:52, Geert Uytterhoeven <geert at linux-m68k.org> wrote:
>
> Hi Ulf,
>
> On Thu, Aug 31, 2023 at 1:39 PM Ulf Hansson <ulf.hansson at linaro.org> wrote:
> > On Thu, 31 Aug 2023 at 11:33, Rafael J. Wysocki <rafael at kernel.org> wrote:
> > > If I may suggest something, I would call this "pmdomain" instead of
> > > "genpd".  I don't think that /drivers/power/ is a particularly
> > > suitable location for it, because it doesn't really have much to do
> > > with power supplies and more to do with device PM.
> >
> > "pmdomain" is probably giving a reasonable good hint of what goes on
> > in this subsystem. This works fine for me, thanks!
>
> Sounds nice!
> All of this lives in <linux/pm_domain.h> (with underscore?) anyway,
> and "PM Domains" is the usual naming, as it covers both Power and
> Clock Domains.
>
> However, although I am quite familiar with genpd, I am still wondering
> what is the meaning of the "generic" part in the name? And what is a
> non-generic PM Domain?

I guess generic here means "works for most cases".

There are certainly a bunch of other "non-generic", like the ACPI,
pm_clk, OMAP2, etc.

Maybe some of them could be converted to genpd, but that's another story.

>
> > > Also, I would move drivers/base/power/domain.c to drivers/pmdomain/
> > > (and rename it to something like core.c), because it would be a better
> > > location for that fiile IMO.
> >
> > We could certainly do that, let's discuss it a bit more.
> >
> > Although, at this point I want to focus on the genpd providers, as to
> > release some of the burden from arm-soc maintainers.
> >
> > > I can also handle future pull requests for this if that's fine with everyone.
> >
> > Thanks a lot for your offer! However, if a re-route is preferred (I
> > think not?), this is probably better suited via arm-soc, as most
> > changes are going to be arm platform specific.
>
> Which brings me to the final question: what is the upstream path
> for changes to drivers/genpd/*/ (or whatever it's gonna be called)?
> Before, we sent PRs to (arm-)soc.  Do you expect us to send them to
> you? There's usually quite some interaction between drivers/soc/reneas/
> and drivers/genpd/renesas (and there are DT binding definitions),
> but not more than with e.g. drivers/clk/renesas/.

I would be happy to pick this up and funnel this via my new genpd
tree. As long as it's coupled with changes affecting "genpd
providers", of course.

I can certainly also collect patches directly from the
mailing-list/patch-tracker too. Whatever works for you the best. Of
course, in that case I need your acks before I pick up the relevant
patches.

If we need "immutable" branches, let's discuss that on a case by case basis.

>
> And I just realized you moved the code and Makefiles to drivers/genpd/,
> but not the Kconfig symbols and logic, which still lives under
> drivers/soc/.  So resolving that (and the name) is something that
> should be resolved sooner rather than later...

In regards to the name, I am relying on input from Linus to make a
final decision before I send a patch. In regards to this, I have also
started working on a documentation patch for genpd. It needs some more
polishing before I can send it though.

When it comes to the Kconfig move, I will send out a series for it, this week.

[...]

Kind regards
Uffe