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

From: Wei Fang <wei.fang@nxp.com>
To: Ahmad Fatoum <a.fatoum@pengutronix.de>,
	"davem@davemloft.net" <davem@davemloft.net>,
	"edumazet@google.com" <edumazet@google.com>,
	"kuba@kernel.org" <kuba@kernel.org>,
	"pabeni@redhat.com" <pabeni@redhat.com>,
	"robh+dt@kernel.org" <robh+dt@kernel.org>,
	"krzysztof.kozlowski+dt@linaro.org" 
	<krzysztof.kozlowski+dt@linaro.org>,
	"shawnguo@kernel.org" <shawnguo@kernel.org>,
	"s.hauer@pengutronix.de" <s.hauer@pengutronix.de>
Cc: Aisheng Dong <aisheng.dong@nxp.com>,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
	Peng Fan <peng.fan@nxp.com>, Jacky Bai <ping.bai@nxp.com>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	dl-linux-imx <linux-imx@nxp.com>,
	"kernel@pengutronix.de" <kernel@pengutronix.de>,
	"sudeep.holla@arm.com" <sudeep.holla@arm.com>,
	"festevam@gmail.com" <festevam@gmail.com>,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>
Subject: RE: [EXT] Re: [PATCH 2/3] arm64: dts: imx8ulp: Add the fec support
Date: Tue, 5 Jul 2022 02:45:10 +0000	[thread overview]
Message-ID: <AM9PR04MB9003A7CE12B40492CB23619788819@AM9PR04MB9003.eurprd04.prod.outlook.com> (raw)
In-Reply-To: <751e1ec6-2d34-44f6-a6c3-775df8a3cea2@pengutronix.de>

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@pengutronix.de> 
Sent: 2022年7月4日 15:07
To: Wei Fang <wei.fang@nxp.com>; davem@davemloft.net; edumazet@google.com; kuba@kernel.org; pabeni@redhat.com; robh+dt@kernel.org; krzysztof.kozlowski+dt@linaro.org; shawnguo@kernel.org; s.hauer@pengutronix.de
Cc: Aisheng Dong <aisheng.dong@nxp.com>; devicetree@vger.kernel.org; Peng Fan <peng.fan@nxp.com>; Jacky Bai <ping.bai@nxp.com>; netdev@vger.kernel.org; linux-kernel@vger.kernel.org; dl-linux-imx <linux-imx@nxp.com>; kernel@pengutronix.de; sudeep.holla@arm.com; festevam@gmail.com; linux-arm-kernel@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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