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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
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treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /Documentation/devicetree/bindings/net/micrel-ksz90x1.txt
parentInitial commit. (diff)
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Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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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 in the PHY OF
+device node. Deprecated, but still supported, these properties can
+also be added 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. The default value is the neutral setting, so setting
+ rxc-skew-ps=<0> actually results in -900 picoseconds adjustment.
+
+ Optional properties:
+
+ Maximum value of 1860, default value 900:
+
+ - rxc-skew-ps : Skew control of RX clock pad
+ - txc-skew-ps : Skew control of TX clock pad
+
+ Maximum value of 900, default value 420:
+
+ - 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
+
+ - micrel,force-master:
+ Boolean, force phy to master mode. Only set this option if the phy
+ reference clock provided at CLK125_NDO pin is used as MAC reference
+ clock because the clock jitter in slave mode is to high (errata#2).
+ Attention: The link partner must be configurable as slave otherwise
+ no link will be established.
+
+Examples:
+
+ 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 {
+ phy = <&phy0>;
+ phy-mode = "rgmii-id";
+ };