Re: [PATCH v6 3/6] net: phy: at803x: add QCA8084 ethernet phy support

[Jie Luo]

On 11/27/2023 1:31 AM, Andrew Lunn wrote:
> > +		/* There are two PCSs available for QCA8084, which support the
> > +		 * following interface modes.
> > +		 *
> > +		 * 1. PHY_INTERFACE_MODE_10G_QXGMII utilizes PCS1 for all
> > +		 * available 4 ports, which is for all link speeds.
> > +		 *
> > +		 * 2. PHY_INTERFACE_MODE_2500BASEX utilizes PCS0 for the
> > +		 * fourth port, which is only for the link speed 2500M same
> > +		 * as QCA8081.
> > +		 *
> > +		 * 3. PHY_INTERFACE_MODE_SGMII utilizes PCS0 for the fourth
> > +		 * port, which is for the link speed 10M, 100M and 1000M same
> > +		 * as QCA8081.
> > +		 */
>
> How are these 3 modes configured? I don't see any software
> configuration of this in these drivers. Can it only by configured by
> strapping?

The interface mode is passed in the .config_init, which is configured
by the PCS driver, the hardware register is located in the PCS, this
driver will be pushed later.

> I think there should be some validation of the phydev->interface
> mode. Are ports 1-3 set to PHY_INTERFACE_MODE_10G_QXGMII? Is port 4
> interface mode consistent with the strapping?
>
> 	  Andrew

All ports(1-4) can be PHY_INTERFACE_MODE_10G_QXGMII, if port4 is
connected with PCS0, which will works on sgmii/2500basex mode,
these configuration is controlled by register instead of boot strapping.