[PATCH 0/5] pmdomain: Restore behaviour for disabling unused PM domains

[Diederik de Haas]

Hi,

On Tue Sep 9, 2025 at 1:11 PM CEST, Ulf Hansson wrote:
> Recent changes to genpd prevents those PM domains being powered-on during
> initialization from being powered-off during the boot sequence. Based upon
> whether CONFIG_PM_CONFIG_PM_GENERIC_DOMAINS_OF is set of not, genpd relies
> on the sync_state mechanism or the genpd_power_off_unused() (which is a
> late_initcall_sync), to understand when it's okay to allow these PM domains
> to be powered-off.
>
> This new behaviour in genpd has lead to problems on different platforms [1].
>
> In this series, I am therefore suggesting to restore the behavior of
> genpd_power_off_unused() along with introducing a new genpd config flag,
> GENPD_FLAG_NO_STAY_ON, to allow genpd OF providers to opt-out from the new
> behaviour.

Is it expected that I'm still seeing this on a Rock64 (rk3328), just
like before [1]?

  [   17.124202] rockchip-pm-domain ff100000.syscon:power-controller: sync_state() pending due to ff300000.gpu
  [   17.129799] rockchip-pm-domain ff100000.syscon:power-controller: sync_state() pending due to ff350000.video-codec
  [   17.140003] rockchip-pm-domain ff100000.syscon:power-controller: sync_state() pending due to ff360000.video-codec

This is with a 6.17-rc5 kernel with this patch set applied.
And it also has this patch from Christian Hewitt added, now in v3:
https://lore.kernel.org/linux-rockchip/20250906120810.1833016-1-christianshewitt@gmail.com/

When I boot into a 6.17-rc5 kernel without any patches applied, I do get
the 2 for ff350000.video-codec and ff360000.video-codec, but not the 
ff300000.gpu one.

Interestingly:
ff300000.gpu -> power-domains = <&power RK3328_PD_GPU>;
ff350000.video-codec -> power-domains = <&power RK3328_PD_VPU>;
ff360000.video-codec -> power-domains = <&power RK3328_PD_VIDEO>;

I would be surprised if that was a coincidence.

Cheers,
  Diederik

[1] https://lore.kernel.org/all/DCK0O99SYSCF.BMBAEUV24C1G@cknow.org/

>
> Kind regards
> Ulf Hansson
>
> [1]
> https://lore.kernel.org/all/20250701114733.636510-1-ulf.hansson@linaro.org/
> https://lore.kernel.org/all/20250902-rk3576-lockup-regression-v1-1-c4a0c9daeb00@collabora.com/
>
> Ulf Hansson (5):
>   pmdomain: core: Restore behaviour for disabling unused PM domains
>   pmdomain: rockchip: Fix regulator dependency with
>     GENPD_FLAG_NO_STAY_ON
>   pmdomain: renesas: rcar-sysc: Don't keep unused PM domains powered-on
>   pmdomain: renesas: rcar-gen4-sysc: Don't keep unused PM domains
>     powered-on
>   pmdomain: renesas: rmobile-sysc: Don't keep unused PM domains
>     powered-on
>
>  drivers/pmdomain/core.c                   | 20 ++++++++++++++------
>  drivers/pmdomain/renesas/rcar-gen4-sysc.c |  1 +
>  drivers/pmdomain/renesas/rcar-sysc.c      |  1 +
>  drivers/pmdomain/renesas/rmobile-sysc.c   |  3 ++-
>  drivers/pmdomain/rockchip/pm-domains.c    |  2 +-
>  include/linux/pm_domain.h                 |  7 +++++++
>  6 files changed, 26 insertions(+), 8 deletions(-)

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