> > Is this to deal with wiring up the SERDES backwards? Is there a more > detailed description in the data sheet? > Sadly, I have not received the datasheet. All comes from studying different versions of the driver. On the BananiPi-R3 Mini the RX pair is reversed: phy14: ethernet-phy@14 { reg = <14>; interrupts-extended = <&pio 48 IRQ_TYPE_EDGE_FALLING>; reset-gpios = <&pio 49 GPIO_ACTIVE_LOW>; reset-assert-us = <10000>; reset-deassert-us = <20000>; phy-mode = "2500base-x"; full-duplex; pause; airoha,rx-pol-reverse; leds { #address-cells = <1>; #size-cells = <0>; led@0 { /* en8811_a_gpio5 */ reg = <0>; color = <LED_COLOR_ID_YELLOW>; function = LED_FUNCTION_LAN; function-enumerator = <1>; default-state = "keep"; linux,default-trigger = "netdev"; }; led@1 { /* en8811_a_gpio4 */ reg = <1>; color = <LED_COLOR_ID_GREEN>; function = LED_FUNCTION_LAN; function-enumerator = <2>; default-state = "keep"; linux,default-trigger = "netdev"; }; }; };