Re: [PATCH 0/9] driver core / pmdomain: Add support for fined grained sync_state
From: Geert Uytterhoeven
Date: Fri Mar 20 2026 - 05:40:49 EST
Hi Ulf,
On Tue, 3 Mar 2026 at 14:23, Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote:
> Since the introduction [1] of the common sync_state support for pmdomains
> (genpd), we have encountered a lot of various interesting problems. In most
> cases the new behaviour of genpd triggered some weird platform specific bugs.
>
> That said, in LPC in Tokyo me and Saravana hosted a session to walk through the
> remaining limitations that we have found for genpd's sync state support. In
> particular, we discussed the problems we have for the so-called onecell power
> domain providers, where a single provider typically provides multiple
> independent power domains, all with their own set of consumers.
>
> In these cases, the generic sync_state mechanism with fw_devlink isn't fine
> grained enough, as we end up waiting for all consumers for all power domains
> before the ->sync_callback gets called for the supplier/provider. In other
> words, we may end up keeping unused power domains powered-on, for no good
> reasons.
>
> The series intends to fix this problem. Please have a look at the commit
> messages for more details.
Thanks for your series!
I gave it a try on various R-Car and R/SH-Mobile platforms, and all
PM Domains are handled fine.
Tested-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds