[PATCH 4/4] arm64: dts: microchip: add LAN969x support

Andrew Lunn andrew at lunn.ch
Sat Dec 6 10:06:41 PST 2025


On Sat, Dec 06, 2025 at 03:53:42PM +0200, Claudiu Beznea wrote:
> > +		port29: port at 29 {
> > +			reg = <29>;
> > +			microchip,bandwidth = <1000>;
> > +			phys = <&serdes 11>;
> > +			phy-handle = <&phy3>;
> > +			phy-mode = "rgmii";
> 
> >From chekpatch:
> 
> WARNING: phy-mode "rgmii" without comment -- delays on the PCB should be
> described, otherwise use "rgmii-id"
> #779: FILE: arch/arm64/boot/dts/microchip/lan9696-ev23x71a.dts:750:
> +                       phy-mode = "rgmii";
> 
> > +			rx-internal-delay-ps = <1000>;
> > +			tx-internal-delay-ps = <1000>;
> > +		};

I did a very quick scan of the patch and missed that. It is great that
checkpatch is now commenting about "rgmii".

1ns is very odd. You need a total of 2ns, so where is the rest coming
from? This definitely needs a comment explaining what is going on.

Also, RGMII typically does not need a SERDES, unless there is
something like an SGMII to RGMII converter being used. So is the phys
property needed?

	Andrew



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