Documentation/devicetree/bindings/net/micrel-ksz9021.txt

   1 Micrel KSZ9021 Gigabit Ethernet PHY
   2
   3 Some boards require special tuning values, particularly when it comes to
   4 clock delays.  You can specify clock delay values by adding
   5 micrel-specific properties to an Ethernet OF device node.
   6
   7 All skew control options are specified in picoseconds.  The minimum
   8 value is 0, and the maximum value is 3000.
   9
  10 Optional properties:
  11  - rxc-skew-ps : Skew control of RXC pad
  12  - rxdv-skew-ps : Skew control of RX CTL pad
  13  - txc-skew-ps : Skew control of TXC pad
  14  - txen-skew-ps : Skew control of TX_CTL pad
  15  - rxd0-skew-ps : Skew control of RX data 0 pad
  16  - rxd1-skew-ps : Skew control of RX data 1 pad
  17  - rxd2-skew-ps : Skew control of RX data 2 pad
  18  - rxd3-skew-ps : Skew control of RX data 3 pad
  19  - txd0-skew-ps : Skew control of TX data 0 pad
  20  - txd1-skew-ps : Skew control of TX data 1 pad
  21  - txd2-skew-ps : Skew control of TX data 2 pad
  22  - txd3-skew-ps : Skew control of TX data 3 pad
  23
  24 Examples:
  25
  26         /* Attach to an Ethernet device with autodetected PHY */
  27         &enet {
  28                 rxc-skew-ps = <3000>;
  29                 rxdv-skew-ps = <0>;
  30                 txc-skew-ps = <3000>;
  31                 txen-skew-ps = <0>;
  32                 status = "okay";
  33         };
  34
  35         /* Attach to an explicitly-specified PHY */
  36         mdio {
  37                 phy0: ethernet-phy@0 {
  38                         rxc-skew-ps = <3000>;
  39                         rxdv-skew-ps = <0>;
  40                         txc-skew-ps = <3000>;
  41                         txen-skew-ps = <0>;
  42                         reg = <0>;
  43                 };
  44         };
  45         ethernet@70000 {
  46                 status = "okay";
  47                 phy = <&phy0>;
  48                 phy-mode = "rgmii-id";
  49         };