Re: [PATCH v3 7/8] arm64: dts: amlogic: t7: khadas-vim4: enable the ethernet port

[Martin Blumenstingl]

On Sat, Oct 10, 2026 at 12:59 PM Lucas Tanure <tanure@xxxxxxxxx> wrote:
[...]
> RGMII needs a delay on each of its two clocks, and on this board
> both come from inside the chips, not from the board traces. The PHY
> adds the one on receive. Its transmit delay does not work here, so the
> controller adds that one.
[...]
> +&ethmac {
> +       status = "okay";
> +       pinctrl-0 = <&eth_pins>, <&eth_rgmii_pins>;
> +       pinctrl-names = "default";
> +       phy-mode = "rgmii-id";
> +       phy-handle = <&external_phy>;
> +       tx-internal-delay-ps = <2000>;
You're stating that RTL8211F's TX delay doesn't work but not explaining why.
I haven't come across this behavior before and I'm worried that that's
an issue with a batch of RTL8211F.
What if the previous/next batch of RTL8211F will have working TX delay
again - wouldn't that mean 4ns delay in total unless the RTL8211F
driver is changed?