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Message-ID: <3df8d4bd-3d38-cecd-6589-ccc1be01b886@linaro.org>
Date:   Fri, 19 Aug 2022 15:47:48 +0300
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Subject: Re: [PATCH 6/6] riscv: dts: microchip: add the mpfs' fabric clock
 control
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To:     Conor Dooley <conor.dooley@microchip.com>,
        Michael Turquette <mturquette@baylibre.com>,
        Stephen Boyd <sboyd@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Daire McNamara <daire.mcnamara@microchip.com>
Cc:     Paul Walmsley <paul.walmsley@sifive.com>,
        Albert Ou <aou@eecs.berkeley.edu>, linux-clk@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-riscv@lists.infradead.org
References: <20220819122259.183600-1-conor.dooley@microchip.com>
 <20220819122259.183600-7-conor.dooley@microchip.com>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <20220819122259.183600-7-conor.dooley@microchip.com>
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Precedence: bulk

On 19/08/2022 15:23, Conor Dooley wrote:
> The "fabric clocks" in current PolarFire SoC device trees are not
> really fixed clocks. Their frequency is set by the bitstream, so having
> them located in -fabric.dtsi is not a problem - they're just as "fixed"
> as the IP blocks etc used in the FPGA fabric.
> However, their configuration can be read at runtime (and to an extent
> they can be controlled, although the intended usage is static
> configurations set by the bitstream) through the system controller bus.
> 

Thank you for your patch. There is something to discuss/improve.

> +&pcie {
> +	clocks = <&fabric_clk1>, <&fabric_clk1>, <&fabric_clk3>;
> +	clock-names = "fic0", "fic1", "fic3";
> +};
> diff --git a/arch/riscv/boot/dts/microchip/mpfs.dtsi b/arch/riscv/boot/dts/microchip/mpfs.dtsi
> index 499c2e63ad35..dd15b6d1a3c9 100644
> --- a/arch/riscv/boot/dts/microchip/mpfs.dtsi
> +++ b/arch/riscv/boot/dts/microchip/mpfs.dtsi
> @@ -236,6 +236,38 @@ clkcfg: clkcfg@20002000 {
>  			#clock-cells = <1>;
>  		};
>  
> +		ccc_se: cccseclk@38010000 {

Although you call it "Clock Conditioning Circuitry", but the role of
this device is a clock-controller, isn't it? If so, node names should be
generic, so "clock-controller".

https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation


Best regards,
Krzysztof