linux-kernel - Re: [RFC V7 2/2] OPP: Allow "opp-hz" and "opp-microvolt" to contain magic values

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Message-ID: <CAL_JsqKr7MsM6iZ_QYO=iCzXNwANEGQGDLFUEwe0Z-p2Z_aMYw@mail.gmail.com>
Date:   Tue, 31 Oct 2017 11:02:51 -0500
From:   Rob Herring <robh+dt@...nel.org>
To:     Viresh Kumar <viresh.kumar@...aro.org>
Cc:     Ulf Hansson <ulf.hansson@...aro.org>,
        Kevin Hilman <khilman@...nel.org>,
        Viresh Kumar <vireshk@...nel.org>, Nishanth Menon <nm@...com>,
        Stephen Boyd <sboyd@...eaurora.org>,
        Rafael Wysocki <rjw@...ysocki.net>,
        "linux-pm@...r.kernel.org" <linux-pm@...r.kernel.org>,
        Vincent Guittot <vincent.guittot@...aro.org>,
        Rajendra Nayak <rnayak@...eaurora.org>,
        Sudeep Holla <sudeep.holla@....com>,
        "devicetree@...r.kernel.org" <devicetree@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [RFC V7 2/2] OPP: Allow "opp-hz" and "opp-microvolt" to contain
 magic values

On Tue, Oct 31, 2017 at 7:47 AM, Viresh Kumar <viresh.kumar@...aro.org> wrote:
> On some platforms the exact frequency or voltage may be hidden from the
> OS by the firmware. Allow such configurations to pass magic values in
> the "opp-hz" or the "opp-microvolt" properties, which should be
> interpreted in a platform dependent way.

Why not a new property for magic values? opp-magic? Don't we want to
know when we have magic values?

Wouldn't magic values in opp-hz get propagated to user space? I can
see the complaints now. "My 4GHz processor is running at 6Hz!" Just
like people complain when BogoMIPS is not high enough.

Rob