Re: [PATCH 1/2] dt-bindings: net: motorcomm: Add chip mode cfg

From: Andrew Lunn
Date: Sat Jul 27 2024 - 07:08:34 EST


On Sat, Jul 27, 2024 at 11:25:25AM +0200, Krzysztof Kozlowski wrote:
> On 27/07/2024 11:20, Frank.Sae wrote:
> > The motorcomm phy (yt8821) supports the ability to
> > config the chip mode of serdes.
> > The yt8821 serdes could be set to AUTO_BX2500_SGMII or
> > FORCE_BX2500.
> > In AUTO_BX2500_SGMII mode, SerDes
> > speed is determined by UTP, if UTP link up
> > at 2.5GBASE-T, SerDes will work as
> > 2500BASE-X, if UTP link up at
> > 1000BASE-T/100BASE-Tx/10BASE-T, SerDes will work
> > as SGMII.
> > In FORCE_BX2500, SerDes always works
> > as 2500BASE-X.

When the SERDES is forced to 2500BaseX, does it perform rate
adaptation? e.g. does it insert pause frames to slow down the MAC?

Maybe look at air_en8811h.c.

Andrew