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Date:   Tue, 5 Jan 2021 18:11:11 +0100
From:   Krzysztof Kozlowski <krzk@kernel.org>
To:     Dmitry Osipenko <digetx@gmail.com>
Cc:     Thierry Reding <thierry.reding@gmail.com>,
        Jonathan Hunter <jonathanh@nvidia.com>,
        Mark Brown <broonie@kernel.org>,
        Liam Girdwood <lgirdwood@gmail.com>,
        Ulf Hansson <ulf.hansson@linaro.org>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Peter Geis <pgwipeout@gmail.com>,
        Nicolas Chauvet <kwizart@gmail.com>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        Kevin Hilman <khilman@kernel.org>,
        Peter De Schrijver <pdeschrijver@nvidia.com>,
        Viresh Kumar <vireshk@kernel.org>,
        Stephen Boyd <sboyd@kernel.org>,
        Michael Turquette <mturquette@baylibre.com>,
        devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org,
        devicetree@vger.kernel.org, dri-devel@lists.freedesktop.org,
        linux-media@vger.kernel.org, linux-tegra@vger.kernel.org,
        linux-clk@vger.kernel.org
Subject: Re: [PATCH v2 00/48] Introduce core voltage scaling for NVIDIA
 Tegra20/30 SoCs
Message-ID: <20210105171111.GC26301@kozik-lap>
References: <20201217180638.22748-1-digetx@gmail.com>
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On Thu, Dec 17, 2020 at 09:05:50PM +0300, Dmitry Osipenko wrote:
> Introduce core voltage scaling for NVIDIA Tegra20/30 SoCs, which reduces
> power consumption and heating of the Tegra chips. Tegra SoC has multiple
> hardware units which belong to a core power domain of the SoC and share
> the core voltage. The voltage must be selected in accordance to a minimum
> requirement of every core hardware unit.
> 
> The minimum core voltage requirement depends on:
> 
>   1. Clock enable state of a hardware unit.
>   2. Clock frequency.
>   3. Unit's internal idling/active state.
> 
> This series is tested on Acer A500 (T20), AC100 (T20), Nexus 7 (T30),
> Ouya (T30), TK1 (T124) and some others. I also added voltage scaling to
> the Ventana (T20) and Cardhu (T30) boards which are tested by NVIDIA's CI
> farm. Tegra30 is now couple degrees cooler on Nexus 7 and stays cool on
> Ouya (instead of becoming burning hot) while system is idling. It should
> be possible to improve this further by implementing a more advanced power
> management features for the kernel drivers.
> 
> The DVFS support is opt-in for all boards, meaning that older DTBs will
> continue to work like they did it before this series. It should be possible
> to easily add the core voltage scaling support for Tegra114+ SoCs based on
> this grounding work later on, if anyone will want to implement it.

The same comment as for your interconnect work: for sets touching
multiple systems please mention the dependencies between patches in the
cover letter. Not as a reply to such remark like I make here, but as a
separate entry in the cover letter.

Best regards,
Krzysztof