[EXT] Re: [PATCH 2/3] arm64: dts: imx8ulp: Add the fec support

[Wei Fang]

Hi Ahmad:

	Thanks for your reply. clock_ext_rmii and clock_ext_ts indeed belong into board DT, I will move them to imx.8ulp-evk.dts and resubmit the patch. And refer to imx8ulp reference manual, the enet_clk_ref only has external clock source, so it is related to specifical board. Therefore, can I delete the enet_clk_ref clock in imx8ulp.dtsi (as shown below) and override the clock and clock-names properties in imx8ulp-evk.dts ?

> +                             clocks = <&cgc1 IMX8ULP_CLK_XBAR_DIVBUS>,
> +                                      <&pcc4 IMX8ULP_CLK_ENET>,
> +                                      <&cgc1 IMX8ULP_CLK_ENET_TS_SEL>;
> +                             clock-names = "ipg", "ahb", "ptp";


-----Original Message-----
From: Ahmad Fatoum <a.fatoum at pengutronix.de> 
Sent: 2022年7月4日 15:07
To: Wei Fang <wei.fang at nxp.com>; davem at davemloft.net; edumazet at google.com; kuba at kernel.org; pabeni at redhat.com; robh+dt at kernel.org; krzysztof.kozlowski+dt at linaro.org; shawnguo at kernel.org; s.hauer at pengutronix.de
Cc: Aisheng Dong <aisheng.dong at nxp.com>; devicetree at vger.kernel.org; Peng Fan <peng.fan at nxp.com>; Jacky Bai <ping.bai at nxp.com>; netdev at vger.kernel.org; linux-kernel at vger.kernel.org; dl-linux-imx <linux-imx at nxp.com>; kernel at pengutronix.de; sudeep.holla at arm.com; festevam at gmail.com; linux-arm-kernel at lists.infradead.org
Subject: [EXT] Re: [PATCH 2/3] arm64: dts: imx8ulp: Add the fec support

Caution: EXT Email

Hello Wei,

On 04.07.22 12:10, Wei Fang wrote:
> +     clock_ext_rmii: clock-ext-rmii {
> +             compatible = "fixed-clock";
> +             clock-frequency = <50000000>;
> +             #clock-cells = <0>;
> +             clock-output-names = "ext_rmii_clk";
> +     };
> +
> +     clock_ext_ts: clock-ext-ts {
> +             compatible = "fixed-clock";
> +             #clock-cells = <0>;
> +             clock-output-names = "ext_ts_clk";
> +     };

How are these SoC-specific? They sound like they belong into board DT.

> +                             clocks = <&cgc1 IMX8ULP_CLK_XBAR_DIVBUS>,
> +                                      <&pcc4 IMX8ULP_CLK_ENET>,
> +                                      <&cgc1 IMX8ULP_CLK_ENET_TS_SEL>,
> +                                      <&clock_ext_rmii>;
> +                             clock-names = "ipg", "ahb", "ptp", 
> + "enet_clk_ref";

I think the default should be the other way round, assume MAC to provide reference clock and allow override on board-level if PHY does it instead.

Cheers,
Ahmad


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