linux-kernel - Re: [PATCH 4/8] cpufreq,vexpress-spc: fix Frequency Invariance (FI) for bL switching

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Message-ID: <20200702114616.kgzxj4ffzgdn2g24@vireshk-i7>
Date:   Thu, 2 Jul 2020 17:16:16 +0530
From:   Viresh Kumar <viresh.kumar@...aro.org>
To:     Ionela Voinescu <ionela.voinescu@....com>
Cc:     rjw@...ysocki.net, catalin.marinas@....com, sudeep.holla@....com,
        will@...nel.org, linux@...linux.org.uk, valentin.schneider@....com,
        mingo@...hat.com, peterz@...radead.org, dietmar.eggemann@....com,
        linux-pm@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-kernel@...r.kernel.org, Liviu Dudau <liviu.dudau@....com>
Subject: Re: [PATCH 4/8] cpufreq,vexpress-spc: fix Frequency Invariance (FI)
 for bL switching

On 02-07-20, 12:41, Ionela Voinescu wrote:
> It was enabled until now, but it was partially broken. If you look over
> the driver you'll see arch_set_freq_scale() being called for both
> is_bL_switching_enabled() and for when it's not [1].

I missed that completely, it was indeed added here:

commit 518accf20629 ("cpufreq: arm_big_little: invoke frequency-invariance setter function")

and so this patch or a version of it is required here.

> If we just don't want frequency invariance for
> is_bL_switching_enabled(), I can just guard the setting of the flag
> suggested by Rafael at 1/8 by !CONFIG_BL_SWITCHER.
> 
> I'll proceed to do that and remove the fix at 4/8.

I think it would be better to do that and avoid any complicate code
unnecessarily here.

-- 
viresh