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Date:   Wed, 5 Aug 2020 11:35:31 +0100
From:   Ionela Voinescu <ionela.voinescu@arm.com>
To:     Viresh Kumar <viresh.kumar@linaro.org>
Cc:     rjw@rjwysocki.net, dietmar.eggemann@arm.com,
        catalin.marinas@arm.com, sudeep.holla@arm.com, will@kernel.org,
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        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 4/7] cpufreq: report whether cpufreq supports
 Frequency Invariance (FI)
Message-ID: <20200805103531.GB4817@arm.com>
References: <20200722093732.14297-1-ionela.voinescu@arm.com>
 <20200722093732.14297-5-ionela.voinescu@arm.com>
 <20200730044346.rgtaikotkgwdpc3m@vireshk-mac-ubuntu>
 <20200803152400.GB20312@arm.com>
 <20200804064656.h25yapthuumdxjw7@vireshk-mac-ubuntu>
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On Tuesday 04 Aug 2020 at 12:16:56 (+0530), Viresh Kumar wrote:
> On 03-08-20, 16:24, Ionela Voinescu wrote:
> > Right, cpufreq_register_driver() should check that at least one of them
> > is present
> 
> > (although currently cpufreq_register_driver() will return
> > -EINVAL if .fast_switch() alone is present - something to be fixed).
> 
> I think it is fine as there is no guarantee from cpufreq core if
> .fast_switch() will get called and so target/target_index must be
> present. We can't do fast-switch today without schedutil (as only that
> enables it) and if a notifier gets registered before the driver, then
> we are gone again.
> 
> > Will do, on both accounts.
> > 
> > 
> > > > +		static_branch_enable_cpuslocked(&cpufreq_set_freq_scale);
> > > > +		pr_debug("%s: Driver %s can provide frequency invariance.",
> > > > +			 __func__, driver->name);
> > > 
> > > I think a simpler print will work well too.
> > > 
> > >                 pr_debug("Freq invariance enabled");
> > > 
> > 
> > I think the right way of reporting this support is important here.
> 
> Yeah, we can't say it is enabled as you explained, though I meant
> something else here then, i.e. getting rid of driver name and
> unimportant stuff. What about this now:
> 
> pr_debug("supports frequency invariance");
> 
> This shall get printed as this finally:
> 
> cpufreq: supports frequency invariance
> 

Will do!

Thanks,
Ionela.

> -- 
> viresh