Re: [PATCH 7/7] arm64: dts: qcom: msm8916: add clocks to the GCC device node

From: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
To: Stephan Gerhold <stephan@gerhold.net>
Cc: Andy Gross <agross@kernel.org>,
	Bjorn Andersson <bjorn.andersson@linaro.org>,
	Stephen Boyd <swboyd@chromium.org>,
	Michael Turquette <mturquette@baylibre.com>,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Taniya Das <quic_tdas@quicinc.com>,
	linux-arm-msm@vger.kernel.org, linux-clk@vger.kernel.org,
	devicetree@vger.kernel.org
Subject: Re: [PATCH 7/7] arm64: dts: qcom: msm8916: add clocks to the GCC device node
Date: Fri, 17 Jun 2022 23:34:24 +0300	[thread overview]
Message-ID: <CAA8EJpozu6PoWC-kOpFB9OSZLVZaZt6ZkUpYo=bOr0zhErkWqA@mail.gmail.com> (raw)
In-Reply-To: <Yqy2YHpl93kEQRYU@gerhold.net>

On Fri, 17 Jun 2022 at 20:14, Stephan Gerhold <stephan@gerhold.net> wrote:
>
> Hi Dmitry,
>
> Thanks for cleaning up MSM8916! :)
>
> On Fri, Jun 17, 2022 at 05:47:14PM +0300, Dmitry Baryshkov wrote:
> > As we are converting this platform to use DT clock bindings, add clocks
> > and clock-names properties to the MMCC device tree node.
> >
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > ---
> >  arch/arm64/boot/dts/qcom/msm8916.dtsi | 14 ++++++++++++++
> >  1 file changed, 14 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/qcom/msm8916.dtsi b/arch/arm64/boot/dts/qcom/msm8916.dtsi
> > index 05472510e29d..e905415b3456 100644
> > --- a/arch/arm64/boot/dts/qcom/msm8916.dtsi
> > +++ b/arch/arm64/boot/dts/qcom/msm8916.dtsi
> > @@ -934,6 +934,20 @@ gcc: clock-controller@1800000 {
> >                       #reset-cells = <1>;
> >                       #power-domain-cells = <1>;
> >                       reg = <0x01800000 0x80000>;
> > +                     clocks = <&rpmcc RPM_SMD_BB_CLK1_PIN>,
>
> This should be <&xo_board> to avoid functional changes.

Ack, thanks for the suggestion.

>
> If we want to change this to the actual votable clock later this should
> probably be <&rpmcc RPM_SMD_XO_CLK_SRC>. AFAIK that clock exists in RPM
> on MSM8916 but was never added to the clk-smd-rpm driver (for MSM8916).
>
> Not sure where the pin-controlled BB_CLK1 is coming from here. :)

It came from the schematics I had at hand (db410c). It uses the
BB_CLK1 together with the enable pin. I'll probably use xo_board for
now and postpone changing this to rpmcc clock until the next attempt
to read msm-3.x code.

-- 
With best wishes
Dmitry