[PATCH 4/5] cpufreq: Add cpufreq driver for the RISC-V RPMI performance service group

[Joshua Yeong]

On Thursday, January 8, 2026 11:27 AM, Viresh Kumar <viresh.kumar at linaro.org> wrote:

> On 06-01-26, 17:21, Joshua Yeong wrote:
> > diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig index 
> > 78702a08364f..9aaa1f71000e 100644
> > --- a/drivers/cpufreq/Kconfig
> > +++ b/drivers/cpufreq/Kconfig
> > @@ -4,8 +4,8 @@ menu "CPU Frequency scaling"
> >  config CPU_FREQ
> >  	bool "CPU Frequency scaling"
> >  	help
> > -	  CPU Frequency scaling allows you to change the clock speed of 
> > -	  CPUs on the fly. This is a nice method to save power, because 
> > +	  CPU Frequency scaling allows you to change the clock speed of
> > +	  CPUs on the fly. This is a nice method to save power, because
> >  	  the lower the CPU clock speed, the less power the CPU consumes.
> >  
> >  	  Note that this driver doesn't automatically change the CPU @@ 
> > -65,7 +65,7 @@ config CPU_FREQ_DEFAULT_GOV_USERSPACE
> >  	select CPU_FREQ_GOV_USERSPACE
> >  	help
> >  	  Use the CPUFreq governor 'userspace' as default. This allows
> > -	  you to set the CPU frequency manually or when a userspace 
> > +	  you to set the CPU frequency manually or when a userspace
> >  	  program shall be able to set the CPU dynamically without having
> >  	  to enable the userspace governor manually.
> >  
> > @@ -134,7 +134,7 @@ config CPU_FREQ_GOV_USERSPACE
> >  	help
> >  	  Enable this cpufreq governor when you either want to set the
> >  	  CPU frequency manually or when a userspace program shall
> > -	  be able to set the CPU dynamically, like on LART 
> > +	  be able to set the CPU dynamically, like on LART
> >  	  <http://www.lartmaker.nl/>.
> >  
> >  	  To compile this driver as a module, choose M here: the @@ -147,11 
> > +147,11 @@ config CPU_FREQ_GOV_ONDEMAND
> >  	select CPU_FREQ_GOV_COMMON
> >  	help
> >  	  'ondemand' - This driver adds a dynamic cpufreq policy governor.
> > -	  The governor does a periodic polling and 
> > +	  The governor does a periodic polling and
> >  	  changes frequency based on the CPU utilization.
> >  	  The support for this governor depends on CPU capability to
> >  	  do fast frequency switching (i.e, very low latency frequency
> > -	  transitions). 
> > +	  transitions).
> >  
> >  	  To compile this driver as a module, choose M here: the
> >  	  module will be called cpufreq_ondemand.
> > @@ -367,4 +367,18 @@ config ACPI_CPPC_CPUFREQ_FIE
> >  
> >  endif
>
> Unrelated changes ?

Hi Viresh,

Will remove the blank space in V2 patch.

>
> > +++ b/drivers/cpufreq/riscv-rpmi-cpufreq.c
> > +static int rpmi_cpufreq_probe(struct platform_device *pdev) {
>
> > +fail_free_channel:
> > +	mbox_free_channel(mpxy_ctx->chan);
> > +
> > +	return ret;
> > +}
> > +
> > +static void rpmi_cpufreq_remove(struct platform_device *pdev) {
> > +	cpufreq_unregister_driver(&rpmi_perf_cpufreq_driver);
>
> Don't need to free mpxy_ctx->chan ?
>

Ok will update this.

> --
> viresh