linux-kernel - Re: [PATCH 2/4] opp: Track device's resources configuration status

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Message-ID: <159747859192.33733.13232258434530046392@swboyd.mtv.corp.google.com>
Date:   Sat, 15 Aug 2020 01:03:11 -0700
From:   Stephen Boyd <sboyd@...nel.org>
To:     Nishanth Menon <nm@...com>, Viresh Kumar <viresh.kumar@...aro.org>,
        Viresh Kumar <vireshk@...nel.org>
Cc:     Viresh Kumar <viresh.kumar@...aro.org>, linux-pm@...r.kernel.org,
        Vincent Guittot <vincent.guittot@...aro.org>,
        Rafael Wysocki <rjw@...ysocki.net>, mka@...omium.org,
        sibis@...eaurora.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/4] opp: Track device's resources configuration status

Quoting Viresh Kumar (2020-08-12 21:28:59)
> The OPP core needs to track if the resources of devices are enabled or
> configured or not, as it disables the resources when target_freq is set
> to 0.
> 
> Handle that with a separate variable to make it easy to maintain.
> 
> Also note that we will unconditionally call clk_set_rate() in the case
> where the resources are getting enabled again. This shouldn't have any
> side effects anyway.

Any reason to want to do that? We'll have to grab the prepare lock in
the clk framework to figure out that there's nothing to do sometimes. If
anything, a comment may help to indicate that we call clk_set_rate()
again, but don't expect it to matter much.