Re: [PATCH net-next 1/2] dt-bindings: net: allwinner: add H616 EMAC1

[James Hilliard]

On Tue, Sep 15, 2026 at 2:33 PM Maxime Chevallier
<maxime.chevallier@xxxxxxxxxxx> wrote:
>
> Hi James,
>
> On 9/15/26 21:03, James Hilliard wrote:
> > The H616 secondary EMAC uses a separate system-control clock register
> > and supports only RMII at 10/100 Mbps. Add its distinct compatible
> > without an older fallback, since using the primary EMAC clock register
> > would not work.
> >
> > Constrain the PHY interface mode to RMII, matching the hardware. The
> > EMAC1 clock register also retains the three-bit TX and five-bit RX delay
> > chains, so allow the existing Allwinner delay properties for this
> > compatible.
>
> I don't think there's such a thing as RMII delays. RMII has a single
> clock, contrary to RGMII that has a TX and a RX clock with a 2ns delay
> between clock and data.
>
> I think it's just a leftover in this IP from the other variants that
> can do RGMII ? You should just be able to drop the comment changes here,
> and same goes for the dwmac patch.

Yeah, looks like most but not all vendor driver variants had RMII delays
configured here, I did test and it doesn't seem to be needed so I went
ahead and dropped the delays in my v2. So yeah, seems to have been
just a leftover config.

>
> Maxime
>