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Date:   Mon, 16 May 2022 09:53:26 +0200
From:   Maxime Ripard <maxime@cerno.tech>
To:     qianfan <qianfanguijin@163.com>
Cc:     linux-sunxi@lists.linux.dev, Rob Herring <robh+dt@kernel.org>,
        Chen-Yu Tsai <wens@csie.org>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        "Rafael J . Wysocki" <rafael@kernel.org>,
        Viresh Kumar <viresh.kumar@linaro.org>,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org
Subject: Re: [PATCH v3 2/2] ARM: dts: sun8i-r40: Add "cpu-supply" node for
 sun8i-r40 based board
Message-ID: <20220516075326.hccburhu743t7p6r@houat>
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On Fri, May 13, 2022 at 04:23:20PM +0800, qianfan wrote:
> > > > There's a similar issue for all the boards that don't have a regula=
tor
> > > > in the first place.
> > > >=20
> > > > The way we worked around this for the other SoCs is to have a DTSI =
with
> > > > the OPPs with a frequency higher than what U-Boot boots with (1008M=
Hz?),
> > > > and only include that DTSI on boards that have a CPU regulator hook=
ed in.
> > > Is this really necessary? It seems like every board based on sun8i-r40
> > > have a cpu regulator.
> > This probably won't be the case whenever someone starts a new design,
> > and then they'll face random crashes for no apparent reason, and waste a
> > lot of time in the process.
> >=20
> > Whereas the alternative is that you would be missing some OPPs,
> > something that is fairly easy to figure out.
>
> How about remove the OPPs which greate that 1.08G in sun8i-r40.dtsi,
> If some boards want to run at a higher frequency, can add them byself
> in the board's file.

You did all the work to support and test them already. It's a bit of a
waste to do that and not include it.

Just do a DTSI like we did for the A64 for example.

Maxime