AR# 65504

PetaLinux 2015.2 Series - Device Tree Generator Creates Errant MDIO Sub-Node for Zynq GEM

Description

As of PetaLinux 2015.2, Xilinx has switched to the Cadence Ethernet driver from Linux mainline. 

This driver expects the PHY node to be a direct child of the Ethernet node. 

The generated pwc.dtsi file adds an MDIO node in between.

 
&gem0 {
  enet-reset = <&gpio0 11 0>;
  phy-mode = "rgmii-id";
  status = "okay";
  xlnx,ptp-enet-clock = <0x69f6bcb>;
  ps7_ethernet_0_mdio: mdio {
     #address-cells = <1>;
     #size-cells = <0>;
  };
 
};

Solution

You can work around this issue by setting the status of the MDIO child node to "disabled" in the system-top.dts file.

For example:

&gem0 {
   phy-handle = <&phy0>;
   ps7_ethernet_0_mdio: mdio {
      status = "disabled";
   };
   
   phy0: phy@0{
        
   };
};
AR# 65504
Date 09/29/2015
Status Active
Type General Article
Tools