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+Micrel KSZ9021/KSZ9031 Gigabit Ethernet PHY
+
+Some boards require special tuning values, particularly when it comes to
+clock delays. You can specify clock delay values by adding
+micrel-specific properties to an Ethernet OF device node.
+
+Note that these settings are applied after any phy-specific fixup from
+phy_fixup_list (see phy_init_hw() from drivers/net/phy/phy_device.c),
+and therefore may overwrite them.
+
+KSZ9021:
+
+ All skew control options are specified in picoseconds. The minimum
+ value is 0, the maximum value is 3000, and it is incremented by 200ps
+ steps.
+
+ Optional properties:
+
+ - rxc-skew-ps : Skew control of RXC pad
+ - rxdv-skew-ps : Skew control of RX CTL pad
+ - txc-skew-ps : Skew control of TXC pad
+ - txen-skew-ps : Skew control of TX CTL pad
+ - rxd0-skew-ps : Skew control of RX data 0 pad
+ - rxd1-skew-ps : Skew control of RX data 1 pad
+ - rxd2-skew-ps : Skew control of RX data 2 pad
+ - rxd3-skew-ps : Skew control of RX data 3 pad
+ - txd0-skew-ps : Skew control of TX data 0 pad
+ - txd1-skew-ps : Skew control of TX data 1 pad
+ - txd2-skew-ps : Skew control of TX data 2 pad
+ - txd3-skew-ps : Skew control of TX data 3 pad
+
+KSZ9031:
+
+ All skew control options are specified in picoseconds. The minimum
+ value is 0, and the maximum is property-dependent. The increment
+ step is 60ps.
+
+ Optional properties:
+
+ Maximum value of 1860:
+
+ - rxc-skew-ps : Skew control of RX clock pad
+ - txc-skew-ps : Skew control of TX clock pad
+
+ Maximum value of 900:
+
+ - rxdv-skew-ps : Skew control of RX CTL pad
+ - txen-skew-ps : Skew control of TX CTL pad
+ - rxd0-skew-ps : Skew control of RX data 0 pad
+ - rxd1-skew-ps : Skew control of RX data 1 pad
+ - rxd2-skew-ps : Skew control of RX data 2 pad
+ - rxd3-skew-ps : Skew control of RX data 3 pad
+ - txd0-skew-ps : Skew control of TX data 0 pad
+ - txd1-skew-ps : Skew control of TX data 1 pad
+ - txd2-skew-ps : Skew control of TX data 2 pad
+ - txd3-skew-ps : Skew control of TX data 3 pad
+
+Examples:
+
+ /* Attach to an Ethernet device with autodetected PHY */
+ &enet {
+ rxc-skew-ps = <3000>;
+ rxdv-skew-ps = <0>;
+ txc-skew-ps = <3000>;
+ txen-skew-ps = <0>;
+ status = "okay";
+ };
+
+ /* Attach to an explicitly-specified PHY */
+ mdio {
+ phy0: ethernet-phy@0 {
+ rxc-skew-ps = <3000>;
+ rxdv-skew-ps = <0>;
+ txc-skew-ps = <3000>;
+ txen-skew-ps = <0>;
+ reg = <0>;
+ };
+ };
+ ethernet@70000 {
+ status = "okay";
+ phy = <&phy0>;
+ phy-mode = "rgmii-id";
+ };