linux-kernel - [PATCH v3 0/4] cpufreq: intel_pstate: Handle powersave governor correctly in the passive mode with HWP

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Date:   Tue, 10 Nov 2020 18:21:56 +0100
From:   "Rafael J. Wysocki" <rjw@...ysocki.net>
To:     Linux PM <linux-pm@...r.kernel.org>
Cc:     "Rafael J. Wysocki" <rafael@...nel.org>,
        Viresh Kumar <viresh.kumar@...aro.org>,
        Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>,
        Zhang Rui <rui.zhang@...el.com>,
        LKML <linux-kernel@...r.kernel.org>,
        Doug Smythies <dsmythies@...us.net>
Subject: [PATCH v3 0/4] cpufreq: intel_pstate: Handle powersave governor correctly in the passive mode with HWP

Hi,

On Monday, November 9, 2020 5:49:49 PM CET Rafael J. Wysocki wrote:
> 
> Even after the changes made very recently, the handling of the powersave
> governor is not exactly as expected when intel_pstate operates in the
> "passive" mode with HWP enabled.
> 
> Namely, in that case HWP is not limited to the policy min frequency, but it
> can scale the frequency up to the policy max limit and it cannot be constrained
> currently, because there are no provisions for that in the framework.
> 
> To address that, patches [1-3/4] add a new governor flag to indicate that this
> governor wants the target frequency to be set to the exact value passed to the
> driver, if possible, and change the powersave and performance governors to have
> that flag set.
> 
> The last patch makes intel_pstate take that flag into account when programming
> the HWP Request MSR.

The v3 simply uses different names for the new governor flags.

Thanks!