linux/Documentation/devicetree/bindings/net/micrel-ksz90x1.txt
Hubert Chaumette 4b405efbe1 Update Micrel KSZ90x1 binding documentation
Renames micrel-ksz9021.txt to micrel-ksz90x1.txt and adds documentation for
the KSZ9031 binding from patch 1. Also adds step increment information, and
note about phy fixups.

Signed-off-by: Hubert Chaumette <hchaumette@adeneo-embedded.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-07 16:51:09 -04:00

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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";
};