Re: Broken imx6 to QCA8334 connection since PHYLIB to PHYLINK conversion

[Ioana Ciornei]

On Tue, Apr 13, 2021 at 09:09:37AM +0200, Michal Vokáč wrote:
> On 12. 04. 21 16:14, Andrew Lunn wrote:
> > > [1] 
> > > https://elixir.bootlin.com/linux/v5.12-rc7/source/arch/arm/boot/dts/imx6dl-yapp4-common.dtsi#L101
> > 
> > &fec {
> >     pinctrl-names = "default";
> >     pinctrl-0 = <&pinctrl_enet>;
> >     phy-mode = "rgmii-id";
> >     phy-reset-gpios = <&gpio1 25 GPIO_ACTIVE_LOW>;
> >     phy-reset-duration = <20>;
> >     phy-supply = <&sw2_reg>;
> >     phy-handle = <&ethphy0>;
> >     status = "okay";
> > 
> >     mdio {
> >             #address-cells = <1>;
> >             #size-cells = <0>;
> > 
> >             phy_port2: phy@1 {
> >                     reg = <1>;
> >             };
> > 
> >             phy_port3: phy@2 {
> >                     reg = <2>;
> >             };
> > 
> >             switch@10 {
> >                     compatible = "qca,qca8334";
> >                     reg = <10>;
> > 
> >                     switch_ports: ports {
> >                             #address-cells = <1>;
> >                             #size-cells = <0>;
> > 
> >                             ethphy0: port@0 {
> >                                     reg = <0>;
> >                                     label = "cpu";
> >                                     phy-mode = "rgmii-id";
> >                                     ethernet = <&fec>;
> > 
> >                                     fixed-link {
> >                                             speed = <1000>;
> >                                             full-duplex;
> >                                     };
> >                             };
> > 
> > The fec phy-handle = <&ethphy0>; is pointing to the PHY of switch port
> > 0. This seems wrong.
> 

Actually, the phy-handle is pointing directly to the switch port 0 node.

> I do not understand. Why this seems wrong?

The phy-handle property should point to a node representing a PHY
device. If a fixed-link subnode is present, no phy-handle is needed.

> The switch has four ports. Ports 2 and 3 have a PHY and are connected
> to the transformers/RJ45 connectors. Port 0 is MII/RMII/RGMII of
> the switch. Port 6 (not used) is a SerDes.
> 
> > Does the FEC have a PHY? Do you connect the FEC
> > and the SWITCH at the RGMII level? Or with two back to back PHYs?
> > 
> > If you are doing it RGMII level, the FEC also needs a fixed-link.
> 
> The FEC does not have PHY and is connected to the switch at RGMII level.
> Adding the fixed-link { speed = <1000>; full-duplex; }; subnode to FEC
> does not help.
> 

Did you also remove the extra phy-handle when you tested?

Ioana