nest-open-source / nest-learning-thermostat / 5.7 / linux-imx-ul / a4dd30f9b9a0afa9654c2b24c5456989091c4ef3 / . / Documentation / devicetree / bindings / net / micrel-ksz90x1.txt

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"; | |

}; |