Re: [PATCH 13/14] arm64: dts: renesas: rzg3s-smarc-som: Enable Ethernet interfaces

From: Geert Uytterhoeven
Date: Wed Dec 06 2023 - 06:28:42 EST


Hi Claudiu,

Thanks for your patch!

On Mon, Nov 20, 2023 at 8:03 AM Claudiu <claudiu.beznea@xxxxxxxxx> wrote:
> From: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
>
> RZ/G3S Smarc Module has Ethernet PHYs (KSZ9131) connected to each Ethernet
> IP. For this add proper DT bindings to enable the Ethernet communication
> though these PHYs.
>
> The interface b/w PHYs and MACs is RGMII. The skew settings were set to
> zero as based on phy-mode (rgmii-id) the KSZ9131 driver enables internal
> DLL which adds 2ns delay b/w clocks (TX/RX) and data signals.

So shouldn't you just use phy-mode "rgmii" instead?

> Different pin settings were applied to TXC, TX_CTL compared with the rest
> of the RGMII pins to comply with requirements for these pins imposed by
> HW manual of RZ/G3S (see chapters "Ether Ch0 Voltage Mode Control
> Register (ETH0_POC)", "Ether Ch1 Voltage Mode Control Register (ETH1_POC)",
> for power source selection, "Ether MII/RGMII Mode Control Register
> (ETH_MODE)" for output-enable and "Input Enable Control Register (IEN_m)"
> for input-enable configurations).
>
> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>

> --- a/arch/arm64/boot/dts/renesas/rzg3s-smarc-som.dtsi
> +++ b/arch/arm64/boot/dts/renesas/rzg3s-smarc-som.dtsi
> @@ -25,7 +25,10 @@ / {
>
> aliases {
> mmc0 = &sdhi0;
> -#if !SW_SD2_EN
> +#if SW_SD2_EN

Cfr. my comment on [PATCH 11/14], this looks odd...

> + eth0 = &eth0;
> + eth1 = &eth1;
> +#else
> mmc2 = &sdhi2;
> #endif
> };
> @@ -81,6 +84,64 @@ vcc_sdhi2: regulator2 {
> };
> };
>
> +#if SW_SD2_EN

Likewise.

> +&eth0 {
> + pinctrl-0 = <&eth0_pins>;
> + pinctrl-names = "default";
> + phy-handle = <&phy0>;
> + phy-mode = "rgmii-id";
> + #address-cells = <1>;
> + #size-cells = <0>;

#{address,size}-cells should be in the SoC-specific .dtsi.
Same for eth1.

> + status = "okay";

The rest LGTM.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds