Re: [PATCH] arm64: dts: qcom: sc8280xp: Flush RSC sleep & wake votes

From: Johan Hovold
Date: Mon May 15 2023 - 07:58:12 EST


On Sun, May 14, 2023 at 07:38:28PM -0700, Bjorn Andersson wrote:
> On Sat, May 13, 2023 at 11:09:07AM +0200, Konrad Dybcio wrote:
> >
> >
> > On 12.05.2023 17:04, Bjorn Andersson wrote:
> > > The rpmh driver will cache sleep and wake votes until the cluster
> > > power-domain is about to enter idle, to avoid unnecessary writes. So
> > > associate the apps_rsc with the cluster pd, so that it can be notified
> > > about this event.
> > >
> > > Without this, only AMC votes are being commited.
> > Ouch.
> >
> > Should we make this required: in bindings and add it to all
> > platforms?
> >
>
> I though this was an optimization and in the absence of this callback
> the driver would just write out wake and sleep sets as well. But per the
> current implementation (and perhaps some underlying cause?) it is indeed
> required, if you care about power consumption.
>
> > >
> > > Signed-off-by: Bjorn Andersson <quic_bjorande@xxxxxxxxxxx>
> > > ---
> > Reviewed-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
> > Fixes: 152d1faf1e2f ("arm64: dts: qcom: add SC8280XP platform")
> >
>
> The Fixes sounds reasonable.

Note that support for the cluster domain was not added until 6.2 and
commit 25092e6100ac ("soc: qcom: rpmh-rsc: Attach RSC to cluster PM
domain") while support for sc8280xp went into 5.19 IIRC.

Johan