linux-kernel - Re: [PATCH v3 6/7] cpufreq: amd-pstate: remove legacy set

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Date: Wed, 07 Feb 2024 14:27:29 +0100
From: Oleksandr Natalenko <oleksandr@...alenko.name>
To: "rafael.j.wysocki@...el.com" <rafael.j.wysocki@...el.com>,
 "Limonciello, Mario" <Mario.Limonciello@....com>,
 "viresh.kumar@...aro.org" <viresh.kumar@...aro.org>,
 "Huang, Ray" <Ray.Huang@....com>,
 "Shenoy, Gautham Ranjal" <gautham.shenoy@....com>,
 "Petkov, Borislav" <Borislav.Petkov@....com>,
 "Yuan, Perry" <Perry.Yuan@....com>
Cc: "Deucher, Alexander" <Alexander.Deucher@....com>,
 "Huang, Shimmer" <Shimmer.Huang@....com>,
 "Du, Xiaojian" <Xiaojian.Du@....com>,
 "Meng, Li (Jassmine)" <Li.Meng@....com>,
 "linux-pm@...r.kernel.org" <linux-pm@...r.kernel.org>,
 "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject:
 Re: [PATCH v3 6/7] cpufreq: amd-pstate: remove legacy set_boost callback for
 passive mode

On středa 7. února 2024 14:17:06 CET Yuan, Perry wrote:
> [AMD Official Use Only - General]
> 
> Hi,
> 
> > -----Original Message-----
> > From: Oleksandr Natalenko <oleksandr@...alenko.name>
> > Sent: Wednesday, February 7, 2024 6:11 PM
> > To: rafael.j.wysocki@...el.com; Limonciello, Mario
> > <Mario.Limonciello@....com>; viresh.kumar@...aro.org; Huang, Ray
> > <Ray.Huang@....com>; Shenoy, Gautham Ranjal
> > <gautham.shenoy@....com>; Petkov, Borislav
> > <Borislav.Petkov@....com>; Yuan, Perry <Perry.Yuan@....com>
> > Cc: Deucher, Alexander <Alexander.Deucher@....com>; Huang, Shimmer
> > <Shimmer.Huang@....com>; Du, Xiaojian <Xiaojian.Du@....com>; Meng,
> > Li (Jassmine) <Li.Meng@....com>; linux-pm@...r.kernel.org; linux-
> > kernel@...r.kernel.org
> > Subject: Re: [PATCH v3 6/7] cpufreq: amd-pstate: remove legacy set_boost
> > callback for passive mode
> >
> > Hello.
> >
> > On středa 7. února 2024 10:21:57 CET Perry Yuan wrote:
> > > With new freqency boost interface supported, legacy boost control
> > > doesn't make sense any more which only support passive mode.
> > > so it can remove the legacy set_boost interface from amd-pstate driver
> > > in case of there is conflict with new boost control logic.
> > >
> > > Signed-off-by: Perry Yuan <perry.yuan@....com>
> > > ---
> > >  drivers/cpufreq/amd-pstate.c | 1 -
> > >  include/linux/amd-pstate.h   | 1 -
> > >  2 files changed, 2 deletions(-)
> > >
> > > diff --git a/drivers/cpufreq/amd-pstate.c
> > > b/drivers/cpufreq/amd-pstate.c index 35791efc6e88..1dd523db3871
> > 100644
> > > --- a/drivers/cpufreq/amd-pstate.c
> > > +++ b/drivers/cpufreq/amd-pstate.c
> > > @@ -1675,7 +1675,6 @@ static struct cpufreq_driver amd_pstate_driver =
> > {
> > >     .exit           = amd_pstate_cpu_exit,
> > >     .suspend        = amd_pstate_cpu_suspend,
> > >     .resume         = amd_pstate_cpu_resume,
> > > -   .set_boost      = amd_pstate_set_boost,
> > >     .update_limits  = amd_pstate_update_limits,
> > >     .name           = "amd-pstate",
> > >     .attr           = amd_pstate_attr,
> > > diff --git a/include/linux/amd-pstate.h b/include/linux/amd-pstate.h
> > > index 465e9295a60c..ab7ca26974da 100644
> > > --- a/include/linux/amd-pstate.h
> > > +++ b/include/linux/amd-pstate.h
> > > @@ -93,7 +93,6 @@ struct amd_cpudata {
> > >     struct amd_aperf_mperf prev;
> > >
> > >     u64     freq;
> > > -   bool    boost_supported;
> >
> > As a result of this removal the kernel-doc for this struct should be amended
> > too because even after this patch is applied the `boost_supported` field
> > remains documented.
> 
> The set_boost is callback used by cpufreq.c, the boost_supported is not documented before the patch.
> We just need to add new sysfs "cpb_boost" introduction in the "/Documentation/admin-guide/pm/amd-pstate.rst"
> The legacy boost is not supported any more, we have no need to document it again as it is.

`boost_supported` as a field of `struct amd_cpudata` is documented in the kernel-doc right before the structure, and this bit should be removed like shown below:

```
--- a/include/linux/amd-pstate.h
+++ b/include/linux/amd-pstate.h
@@ -56,7 +56,6 @@ struct amd_aperf_mperf {
  * @cur: Difference of Aperf/Mperf/tsc count between last and current sample
  * @prev: Last Aperf/Mperf/tsc count value read from register
  * @freq: current cpu frequency value
- * @boost_supported: check whether the Processor or SBIOS supports boost mode
  * @hw_prefcore: check whether HW supports preferred core featue.
  * 		  Only when hw_prefcore and early prefcore param are true,
  * 		  AMD P-State driver supports preferred core featue.

```

> Perry.
> 
> >
> > >     bool    hw_prefcore;
> > >
> > >     /* EPP feature related attributes*/
> > >
> >
> >
> > --
> > Oleksandr Natalenko (post-factum)
> 


-- 
Oleksandr Natalenko (post-factum)
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