Re: [PATCH v3 11/21] cpufreq: amd: add amd-pstate frequencies attributes

From: Huang Rui
Date: Wed Nov 10 2021 - 07:28:52 EST


On Sat, Nov 06, 2021 at 02:59:55AM +0800, Fontenot, Nathan wrote:
> On 10/29/21 8:02 AM, Huang Rui wrote:
> > Introduce sysfs attributes to get the different level processor
> > frequencies.
> >
> > Signed-off-by: Huang Rui <ray.huang@xxxxxxx>
> > ---
> > drivers/cpufreq/amd-pstate.c | 63 ++++++++++++++++++++++++++++++++++++
> > 1 file changed, 63 insertions(+)
> >
> > diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> > index 9af27ac1f818..8cf1e80f44e0 100644
> > --- a/drivers/cpufreq/amd-pstate.c
> > +++ b/drivers/cpufreq/amd-pstate.c
> > @@ -485,6 +485,68 @@ static int amd_pstate_cpu_exit(struct cpufreq_policy *policy)
> > return 0;
> > }
> >
> > +/* Sysfs attributes */
> > +
> > +/* This frequency is to indicate the maximum hardware frequency.
> > + * If boost is not active but supported, the frequency will be larger than the
> > + * one in cpuinfo.
> > + */
> > +static ssize_t show_amd_pstate_max_freq(struct cpufreq_policy *policy,
> > + char *buf)
> > +{
> > + int max_freq;
> > + struct amd_cpudata *cpudata;
> > +
> > + cpudata = policy->driver_data;
> > +
> > + max_freq = amd_get_max_freq(cpudata);
> > + if (max_freq < 0)
> > + return max_freq;
> > +
> > + return sprintf(&buf[0], "%u\n", max_freq);
> > +}
> > +
> > +static ssize_t show_amd_pstate_nominal_freq(struct cpufreq_policy *policy,
> > + char *buf)
> > +{
> > + int nominal_freq;
> > + struct amd_cpudata *cpudata;
> > +
> > + cpudata = policy->driver_data;
> > +
> > + nominal_freq = amd_get_nominal_freq(cpudata);
> > + if (nominal_freq < 0)
> > + return nominal_freq;
> > +
> > + return sprintf(&buf[0], "%u\n", nominal_freq);
> > +}
>
> The nominal_freq valus is already reported in sysfs by drivers/acpi since this
> value is part of the ACPI spec. Is there a reason to have multiple sysfs entries
> for the same value?
>

I will clean them up in V4. Thanks!

Ray