Hey folks, I'm having a problem with a custom i.mx6ul board. When DSA is loaded I can't get access to the switch via MDIO, but the DSA is working properly. I set up a bridge for testing and the switch is in forwarding mode and i can ping the board. But the MDIO access isn't working at address 2 for the switch. When I delete the DSA from the devicetree and start the board up, I can access the switch via MDIO.
With DSA up and running: mii -i 2 0 0x9800 mii -i 2 1 phyid:2, reg:0x01 -> 0x4000 mii -i 2 0 0x9803 mii -i 2 1 phyid:2, reg:0x01 -> 0x4000 mii -i 2 1 0x1883 mii -i 2 1 phyid:2, reg:0x01 -> 0x4000 No DSA: mii -i 2 0 0x9800 mii -i 2 1 phyid:2, reg:0x01 -> 0xde04 mii -i 2 0 0x9803 mii -i 2 1 phyid:2, reg:0x01 -> 0x3901 mii -i 2 1 0x1883 mii -i 2 1 phyid:2, reg:0x01 -> 0x1883 Here is the device tree for our board: &mdio0 { switch0: switch0@2 { compatible = "marvell,mv88e6190"; reg = <2>; pinctrl-0 = <&pinctrl_gpios>; reset-gpios = <&gpio4 16 GPIO_ACTIVE_LOW>; dsa,member = <0 0>; ports { #address-cells = <1>; #size-cells = <0>; port@0 { reg = <0>; label = "cpu"; ethernet = <&fec1>; phy-mode = "rmii"; fixed-link { speed = <100>; full-duplex; }; }; port@1 { reg = <1>; label = "lan1"; }; port@2 { reg = <2>; label = "lan2"; }; port@3 { reg = <3>; label = "lan3"; }; port@4 { reg = <4>; label = "lan4"; }; port@5 { reg = <5>; label = "lan5"; }; port@6 { reg = <6>; label = "lan6"; }; port@7 { reg = <7>; label = "lan7"; }; port@8 { reg = <8>; label = "lan8"; }; port@9 { reg = <9>; label = "serdes1"; fixed-link { speed = <1000>; full-duplex; }; }; port@10 { reg = <10>; label = "serdes2"; fixed-link { speed = <1000>; full-duplex; }; }; }; }; }; On a different custom board we have another switching chip in single chip addressing mode the MDIO access works like a charm with activated DSA. Currently I'm on linux-4.14.118. Other kernels (4.19.55, 5.1.14) I've tested stuck at or reboot while DSA is loading. Same devicetree there. Let me know if you need some more input. Thanks in advance for your help. Best regards, Benjamin Beckmeyer