Re: [PATCH 2/2] clk: qcom: add IPQ9574 interconnect clocks support

From: Varadarajan Narayanan <quic_varada@quicinc.com>
To: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Cc: <andersson@kernel.org>, <konrad.dybcio@linaro.org>,
	<robh@kernel.org>, <krzysztof.kozlowski+dt@linaro.org>,
	<conor+dt@kernel.org>, <mturquette@baylibre.com>,
	<sboyd@kernel.org>, <djakov@kernel.org>,
	<linux-arm-msm@vger.kernel.org>, <devicetree@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>, <linux-clk@vger.kernel.org>,
	<linux-pm@vger.kernel.org>
Subject: Re: [PATCH 2/2] clk: qcom: add IPQ9574 interconnect clocks support
Date: Thu, 21 Mar 2024 15:26:01 +0530	[thread overview]
Message-ID: <ZfwEMUBdlQHYz/+h@hu-varada-blr.qualcomm.com> (raw)
In-Reply-To: <4079ddcf-425d-4194-93b8-ee113864541e@linaro.org>

On Thu, Mar 21, 2024 at 08:25:15AM +0100, Krzysztof Kozlowski wrote:
> On 21/03/2024 05:31, Varadarajan Narayanan wrote:
> > Unlike MSM platforms that manage NoC related clocks and scaling
> > from RPM, IPQ SoCs dont involve RPM in managing NoC related
> > clocks and there is no NoC scaling.
>
> If these are clocks, expose them as clocks, not as interconnects.

Earlier IPQ9574 PCIe patches were NAK-ed when these were exposed
as clocks. Please refer to the following discussions

https://lore.kernel.org/linux-arm-msm/CAA8EJpq0uawrOBHA8XHygEpGYF--HyxJWxKG44iiFdAZZz7O2w@mail.gmail.com/
https://lore.kernel.org/linux-arm-msm/CAA8EJppabK8j9T40waMv=t-1aksXfqJibWuS41GhruzLhpatrg@mail.gmail.com/

Dmitry had said
	<quote>
	I'd kindly suggest implementing the NoC attachment
	properly. In the end, other Qualcomm platforms use ICC
	drivers, so by following this pattern we will have more
	common code paths.
	</quote>

Hence posted these patches to get feedback.

> > However, there is a requirement to enable some NoC interface
> > clocks for accessing the peripheral controllers present on
> > these NoCs.
> >
> > Hence adding a minimalistic interconnect driver that can enable
> > the relevant clocks. This is similar to msm8996-cbf's usage of
> > icc-clk framework.
> >
> > Signed-off-by: Varadarajan Narayanan <quic_varada@quicinc.com>
> > ---
> >  arch/arm64/boot/dts/qcom/ipq9574.dtsi |  2 +
>
> DTS is always, ALWAYS, separate.

Ok.

>
> >  drivers/clk/qcom/gcc-ipq9574.c        | 75 ++++++++++++++++++++++++++-
> >  2 files changed, 76 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/arm64/boot/dts/qcom/ipq9574.dtsi b/arch/arm64/boot/dts/qcom/ipq9574.dtsi
> > index 7f2e5cbf3bbb..efffbd085715 100644
> > --- a/arch/arm64/boot/dts/qcom/ipq9574.dtsi
> > +++ b/arch/arm64/boot/dts/qcom/ipq9574.dtsi
> > @@ -11,6 +11,7 @@
> >  #include <dt-bindings/interrupt-controller/arm-gic.h>
> >  #include <dt-bindings/reset/qcom,ipq9574-gcc.h>
> >  #include <dt-bindings/thermal/thermal.h>
> > +#include <dt-bindings/interconnect/qcom,ipq9574.h>
>
> Keep the order,

Ok.

Thanks
Varada