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authorTom Rini <trini@konsulko.com>2019-07-18 20:32:07 -0400
committerTom Rini <trini@konsulko.com>2019-07-18 20:32:07 -0400
commit62a09f45ab824c5fdebf0217c774bededf223232 (patch)
tree32ad59e054f8c1640374b0eee25eb4e6695e2a16 /doc
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parentbbfc562719c463ba6e7b03125aedd5720a325d2d (diff)
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Merge branch 'master' of git://git.denx.de/u-boot-net
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+The expected structure of an MDIO MUX device tree node is described here. This
+is heavily based on current Linux specification.
+One notable difference to Linux is that mdio-parent-bus is currently required
+by U-Boot, not optional as is in Linux. Current U-Boot MDIO MUX udevice class
+implementation does not have specific support for MDIOs with an integrated MUX,
+the property should be made optional if such support is added.
+
+The MDIO buses downstream of the MUX should be described in the device tree as
+child nodes as indicated below.
+
+Required properties:
+mdio-parent-bus = a phandle to the MDIO bus used to perform actual I/O. This is
+ typically a real MDIO device, unless there are cascaded MUXes.
+#address-cells = <1>, each MDIO group is identified by one 32b value.
+#size-cells = <0>
+
+Other properties:
+The properties described here are sufficient for MDIO MUX DM class code, but
+MUX drivers may define additional properties, either required or optional.
+
+Required properties in child nodes:
+reg = value to be configured on the MUX to select the respective downstream
+ MDIO.
+
+Child nodes should normally contain PHY nodes, referenced by phandle from
+ethernet nodes of the eth interfaces using these PHYs.
+
+Example structure, extracted from Linux bindings document:
+
+ /* The parent MDIO bus. */
+ smi1: mdio@1180000001900 {
+ compatible = "cavium,octeon-3860-mdio";
+ #address-cells = <1>;
+ #size-cells = <0>;
+ reg = <0x11800 0x00001900 0x0 0x40>;
+ };
+ /*
+ * An NXP sn74cbtlv3253 dual 1-of-4 switch controlled by a
+ * pair of GPIO lines. Child busses 2 and 3 populated with 4
+ * PHYs each.
+ */
+ mdio-mux {
+ compatible = "mdio-mux-gpio";
+ gpios = <&gpio1 3 0>, <&gpio1 4 0>;
+ mdio-parent-bus = <&smi1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ mdio@2 {
+ reg = <2>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ phy11: ethernet-phy@1 {
+ reg = <1>;
+ compatible = "marvell,88e1149r";
+ marvell,reg-init = <3 0x10 0 0x5777>,
+ <3 0x11 0 0x00aa>,
+ <3 0x12 0 0x4105>,
+ <3 0x13 0 0x0a60>;
+ interrupt-parent = <&gpio>;
+ interrupts = <10 8>; /* Pin 10, active low */
+ };
+ phy12: ethernet-phy@2 {
+ reg = <2>;
+ compatible = "marvell,88e1149r";
+ marvell,reg-init = <3 0x10 0 0x5777>,
+ <3 0x11 0 0x00aa>,
+ <3 0x12 0 0x4105>,
+ <3 0x13 0 0x0a60>;
+ interrupt-parent = <&gpio>;
+ interrupts = <10 8>; /* Pin 10, active low */
+ };
+ phy13: ethernet-phy@3 {
+ reg = <3>;
+ compatible = "marvell,88e1149r";
+ marvell,reg-init = <3 0x10 0 0x5777>,
+ <3 0x11 0 0x00aa>,
+ <3 0x12 0 0x4105>,
+ <3 0x13 0 0x0a60>;
+ interrupt-parent = <&gpio>;
+ interrupts = <10 8>; /* Pin 10, active low */
+ };
+ phy14: ethernet-phy@4 {
+ reg = <4>;
+ compatible = "marvell,88e1149r";
+ marvell,reg-init = <3 0x10 0 0x5777>,
+ <3 0x11 0 0x00aa>,
+ <3 0x12 0 0x4105>,
+ <3 0x13 0 0x0a60>;
+ interrupt-parent = <&gpio>;
+ interrupts = <10 8>; /* Pin 10, active low */
+ };
+ };
+ mdio@3 {
+ reg = <3>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ phy21: ethernet-phy@1 {
+ reg = <1>;
+ compatible = "marvell,88e1149r";
+ marvell,reg-init = <3 0x10 0 0x5777>,
+ <3 0x11 0 0x00aa>,
+ <3 0x12 0 0x4105>,
+ <3 0x13 0 0x0a60>;
+ interrupt-parent = <&gpio>;
+ interrupts = <12 8>; /* Pin 12, active low */
+ };
+ phy22: ethernet-phy@2 {
+ reg = <2>;
+ compatible = "marvell,88e1149r";
+ marvell,reg-init = <3 0x10 0 0x5777>,
+ <3 0x11 0 0x00aa>,
+ <3 0x12 0 0x4105>,
+ <3 0x13 0 0x0a60>;
+ interrupt-parent = <&gpio>;
+ interrupts = <12 8>; /* Pin 12, active low */
+ };
+ phy23: ethernet-phy@3 {
+ reg = <3>;
+ compatible = "marvell,88e1149r";
+ marvell,reg-init = <3 0x10 0 0x5777>,
+ <3 0x11 0 0x00aa>,
+ <3 0x12 0 0x4105>,
+ <3 0x13 0 0x0a60>;
+ interrupt-parent = <&gpio>;
+ interrupts = <12 8>; /* Pin 12, active low */
+ };
+ phy24: ethernet-phy@4 {
+ reg = <4>;
+ compatible = "marvell,88e1149r";
+ marvell,reg-init = <3 0x10 0 0x5777>,
+ <3 0x11 0 0x00aa>,
+ <3 0x12 0 0x4105>,
+ <3 0x13 0 0x0a60>;
+ interrupt-parent = <&gpio>;
+ interrupts = <12 8>; /* Pin 12, active low */
+ };
+ };
+ };