Re: [PATCH 4/4] cpufreq: scmi: Support the power scale in micro-Watts in SCMI v3.1

[Lukasz Luba]

On 7/5/22 10:25, Daniel Lezcano wrote:
> On 22/06/2022 16:58, Lukasz Luba wrote:
> > The SCMI v3.1 adds support for power values in micro-Watts. They are not
> > always in milli-Watts anymore (ignoring the bogo-Watts). Thus, the power
> > must be converted conditionally before sending to Energy Model. Add the
> > logic which handles the needed checks and conversions.
> >
> > Signed-off-by: Lukasz Luba <lukasz.luba@xxxxxxx>
> > ---
> >   drivers/cpufreq/scmi-cpufreq.c | 15 ++++++++++-----
> >   1 file changed, 10 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/cpufreq/scmi-cpufreq.c 
> > b/drivers/cpufreq/scmi-cpufreq.c
> > index bfd35583d653..513a071845c2 100644
> > --- a/drivers/cpufreq/scmi-cpufreq.c
> > +++ b/drivers/cpufreq/scmi-cpufreq.c
> > @@ -100,7 +100,7 @@ static int __maybe_unused
> >   scmi_get_cpu_power(struct device *cpu_dev, unsigned long *power,
> >              unsigned long *KHz)
> >   {
> > -    bool power_scale_mw = perf_ops->power_scale_mw_get(ph);
> > +    enum scmi_power_scale power_scale = perf_ops->power_scale_get(ph);
> >       unsigned long Hz;
> >       int ret, domain;
> > @@ -114,8 +114,8 @@ scmi_get_cpu_power(struct device *cpu_dev, 
> > unsigned long *power,
> >       if (ret)
> >           return ret;
> > -    /* Provide bigger resolution power to the Energy Model */
> > -    if (power_scale_mw)
> > +    /* Convert the power to uW if it is mW (ignore bogoW) */
> > +    if (power_scale == SCMI_POWER_MILLIWATTS)
> >           *power *= MICROWATT_PER_MILLIWATT;
> >       /* The EM framework specifies the frequency in KHz. */
> > @@ -255,8 +255,9 @@ static int scmi_cpufreq_exit(struct cpufreq_policy 
> > *policy)
> >   static void scmi_cpufreq_register_em(struct cpufreq_policy *policy)
> >   {
> >       struct em_data_callback em_cb = EM_DATA_CB(scmi_get_cpu_power);
> > -    bool power_scale_mw = perf_ops->power_scale_mw_get(ph);
> > +    enum scmi_power_scale power_scale = perf_ops->power_scale_get(ph);
> >       struct scmi_data *priv = policy->driver_data;
> > +    bool em_power_scale = false;
>
> Just pass 'false' to em_dev_register_perf_domain()

We cannot,

> >       /*
> >        * This callback will be called for each policy, but we don't 
> > need to
> > @@ -268,9 +269,13 @@ static void scmi_cpufreq_register_em(struct 
> > cpufreq_policy *policy)
> >       if (!priv->nr_opp)
> >           return;
> > +    if (power_scale == SCMI_POWER_MILLIWATTS
> > +        || power_scale == SCMI_POWER_MICROWATTS)
> > +        em_power_scale = true;
> > +

because sometimes it's 'true'.

> >       em_dev_register_perf_domain(get_cpu_device(policy->cpu), 
> > priv->nr_opp,
> >                       &em_cb, priv->opp_shared_cpus,
> > -                    power_scale_mw);
> > +                    em_power_scale);

Then we just use the variable here in single call.

> >   }
> >   static struct cpufreq_driver scmi_cpufreq_driver = {