From 88d2b1abea95db33d4238dbaed0694b1a36565bb Mon Sep 17 00:00:00 2001 From: Alex Marginean Date: Tue, 16 Jul 2019 11:21:18 +0300 Subject: doc: bindings: Add binding for register driven MDIO muxes This binding documents two properties that describe the registers used to perform MUX selection. Signed-off-by: Alex Marginean Acked-by: Joe Hershberger Reviewed-by: Bin Meng --- doc/device-tree-bindings/net/mdio-mux-reg.txt | 82 +++++++++++++++++++++++++++ 1 file changed, 82 insertions(+) create mode 100644 doc/device-tree-bindings/net/mdio-mux-reg.txt (limited to 'doc') diff --git a/doc/device-tree-bindings/net/mdio-mux-reg.txt b/doc/device-tree-bindings/net/mdio-mux-reg.txt new file mode 100644 index 0000000000..0ac34dc423 --- /dev/null +++ b/doc/device-tree-bindings/net/mdio-mux-reg.txt @@ -0,0 +1,82 @@ +Device tree structures used by register based MDIO muxes is described here. +This binding is based on reg-mux.txt binding in Linux and is currently used by +mdio-mux-i2creg driver in U-Boot. + +Required properties: +#mux-control-cells = <1> indicates how many registers are used for mux + selection. mux-reg-mask property described below must + include this number of pairs. +mux-reg-masks = describes pairs of register offset and register mask. + Register bits enabled in mask are set to the selection + value defined in reg property of child MDIOs to control + selection. +Properties described in mdio-mux.txt also apply. + +Example structure, used on Freescale LS1028A QDS board: + +&i2c0 { + status = "okay"; + u-boot,dm-pre-reloc; + + fpga@66 { + #address-cells = <1>; + #size-cells = <0>; + compatible = "simple-mfd"; + reg = <0x66>; + + mux-mdio@54 { + #address-cells = <1>; + #size-cells = <0>; + compatible = "mdio-mux-i2creg"; + reg = <0x54>; + #mux-control-cells = <1>; + mux-reg-masks = <0x54 0xf0>; + mdio-parent-bus = <&mdio0>; + + /* on-board MDIO with a single RGMII PHY */ + mdio@00 { + #address-cells = <1>; + #size-cells = <0>; + reg = <0x00>; + + /* on-board 1G RGMII PHY */ + qds_phy0: phy@5 { + reg = <5>; + }; + }; + /* card slot 1 */ + mdio@40 { + #address-cells = <1>; + #size-cells = <0>; + reg = <0x40>; + /* VSC8234 1G SGMII card */ + sgmii_port0: phy@1c { + reg = <0x1c>; + }; + }; + /* card slot 2 */ + mdio@50 { + #address-cells = <1>; + #size-cells = <0>; + reg = <0x50>; + }; + /* card slot 3 */ + mdio@60 { + #address-cells = <1>; + #size-cells = <0>; + reg = <0x60>; + }; + /* card slot 4 */ + mdio@70 { + #address-cells = <1>; + #size-cells = <0>; + reg = <0x70>; + }; + }; + }; +}; + +/* Parent MDIO, defined in SoC .dtsi file, just enabled here */ +&mdio0 { + status = "okay"; +}; -- cgit v1.2.3