On Fri, 2022-04-15 at 14:24 +0200, AngeloGioacchino Del Regno wrote:
> Il 15/04/22 07:59, Rex-BC Chen ha scritto:
> > From: Jia-Wei Chang <jia-wei.chang@mediatek.com>
> >
> > We found the buck voltage may not be exactly the same with what we
> > set
> > because CPU may share the same buck with other module.
> > Therefore, we need to record the previous desired value instead of
> > reading
> > it from regulators.
> >
> > Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
> > Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com>
> > Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
> > ---
> > drivers/cpufreq/mediatek-cpufreq.c | 17 +++++++++++++----
> > 1 file changed, 13 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/cpufreq/mediatek-cpufreq.c
> > b/drivers/cpufreq/mediatek-cpufreq.c
> > index ff27f77e8ee6..fa8b193bf27b 100644
> > --- a/drivers/cpufreq/mediatek-cpufreq.c
> > +++ b/drivers/cpufreq/mediatek-cpufreq.c
> > @@ -40,6 +40,7 @@ struct mtk_cpu_dvfs_info {
> > struct list_head list_head;
> > int intermediate_voltage;
> > bool need_voltage_tracking;
> > + int pre_vproc;
> > };
> >
> > static LIST_HEAD(dvfs_info_list);
> > @@ -191,11 +192,17 @@ static int
> > mtk_cpufreq_voltage_tracking(struct mtk_cpu_dvfs_info *info,
> >
> > static int mtk_cpufreq_set_voltage(struct mtk_cpu_dvfs_info
> > *info, int vproc)
> > {
> > + int ret;
> > +
> > if (info->need_voltage_tracking)
> > - return mtk_cpufreq_voltage_tracking(info, vproc);
> > + ret = mtk_cpufreq_voltage_tracking(info, vproc);
> > else
> > - return regulator_set_voltage(info->proc_reg, vproc,
> > - vproc + VOLT_TOL);
> > + ret = regulator_set_voltage(info->proc_reg, vproc,
> > + MAX_VOLT_LIMIT);
> > + if (!ret)
> > + info->pre_vproc = vproc;
> > +
> > + return ret;
> > }
> >
> > static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
> > @@ -213,7 +220,9 @@ static int mtk_cpufreq_set_target(struct
> > cpufreq_policy *policy,
> > inter_vproc = info->intermediate_voltage;
> >
> > pre_freq_hz = clk_get_rate(cpu_clk);
> > - pre_vproc = regulator_get_voltage(info->proc_reg);
> > + pre_vproc = info->pre_vproc;
> > + if (pre_vproc <= 0)
> > + pre_vproc = regulator_get_voltage(info->proc_reg);
>
> I would do it like that, instead:
>
> if (unlikely(info->pre_vproc <= 0))
> pre_vproc = regulator_get_voltage(info->proc_reg);
> else
> pre_vproc = info->pre_vproc;
>
> ....as even though it is indeed possible that info->pre_vproc is <=
> 0, it is
> very unlikely to happen ;-)
> This also solves a 'pre_vproc' double assignment issue, by the way.
>
> Cheers,
> Angelo
>
>
>
Hello Angelo,
OK, I will add this in next version.
Thanks for your suggestion.
BRs,
Rex