Re: [RESEND][PATCH v2 4/4] soc: samsung: exynos-asv: Update Energy Model after adjusting voltage

[Lukasz Luba]

On 3/27/24 12:56, Dietmar Eggemann wrote:
> On 26/03/2024 21:12, Lukasz Luba wrote:
> > Hi Dietmar,
> >
> > On 3/26/24 11:20, Dietmar Eggemann wrote:
> > > On 22/03/2024 12:08, Lukasz Luba wrote:
> > >
> > > [...]
> > >
> > > > @@ -97,9 +98,17 @@ static int exynos_asv_update_opps(struct
> > > > exynos_asv *asv)
> > > >                last_opp_table = opp_table;
> > > >                  ret = exynos_asv_update_cpu_opps(asv, cpu);
> > > > -            if (ret < 0)
> > > > +            if (!ret) {
> > > > +                /*
> > > > +                 * When the voltage for OPPs successfully
> > > > +                 * changed, update the EM power values to
> > > > +                 * reflect the reality and not use stale data
> > >
> > > At this point, can we really say that the voltage has changed?
> > >
> > >     exynos_asv_update_cpu_opps()
> > >
> > >       ...
> > >       ret = dev_pm_opp_adjust_voltage()
> > >       if (!ret)
> > >         em_dev_update_chip_binning()
> > >       ...
> > >
> > > dev_pm_opp_adjust_voltage() also returns 0 when the voltage value stays
> > > the same?
> > >
> > > [...]
> >
> > The comment for the dev_pm_opp_adjust_voltage() says that it
> > returns 0 if no modification was done or modification was
> > successful. So I cannot distinguish in that driver code, but
> > also there is no additional need to do it IMO (even framework
> > doesn't do this).
>
> Precisely. That's why the added comment in exynos_asv_update_opps():
> "When the voltage for OPPs successfully __changed__, ..." is somehow
> misleading IMHO.

I got your point. Let me re-phrase that comment to reflect this
OPP function return properly.