xref: /openbmc/u-boot/doc/device-tree-bindings/net/fixed-link.txt (revision db40c1aa1c100d8a9e33206575efd8b3678f31db)
1*db40c1aaSHannes SchmelzerFixed link Device Tree binding
2*db40c1aaSHannes Schmelzer------------------------------
3*db40c1aaSHannes Schmelzer
4*db40c1aaSHannes SchmelzerSome Ethernet MACs have a "fixed link", and are not connected to a
5*db40c1aaSHannes Schmelzernormal MDIO-managed PHY device. For those situations, a Device Tree
6*db40c1aaSHannes Schmelzerbinding allows to describe a "fixed link".
7*db40c1aaSHannes Schmelzer
8*db40c1aaSHannes SchmelzerSuch a fixed link situation is described by creating a 'fixed-link'
9*db40c1aaSHannes Schmelzersub-node of the Ethernet MAC device node, with the following
10*db40c1aaSHannes Schmelzerproperties:
11*db40c1aaSHannes Schmelzer
12*db40c1aaSHannes Schmelzer* 'speed' (integer, mandatory), to indicate the link speed. Accepted
13*db40c1aaSHannes Schmelzer  values are 10, 100 and 1000
14*db40c1aaSHannes Schmelzer* 'full-duplex' (boolean, optional), to indicate that full duplex is
15*db40c1aaSHannes Schmelzer  used. When absent, half duplex is assumed.
16*db40c1aaSHannes Schmelzer* 'pause' (boolean, optional), to indicate that pause should be
17*db40c1aaSHannes Schmelzer  enabled.
18*db40c1aaSHannes Schmelzer* 'asym-pause' (boolean, optional), to indicate that asym_pause should
19*db40c1aaSHannes Schmelzer  be enabled.
20*db40c1aaSHannes Schmelzer
21*db40c1aaSHannes SchmelzerExamples:
22*db40c1aaSHannes Schmelzer
23*db40c1aaSHannes Schmelzerethernet@0 {
24*db40c1aaSHannes Schmelzer	...
25*db40c1aaSHannes Schmelzer	fixed-link {
26*db40c1aaSHannes Schmelzer	      speed = <1000>;
27*db40c1aaSHannes Schmelzer	      full-duplex;
28*db40c1aaSHannes Schmelzer	};
29*db40c1aaSHannes Schmelzer	...
30*db40c1aaSHannes Schmelzer};
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