> When does someone use rgmii-txid and rgmii-rxid? When there is an extra long RX clock line on the PCB, but not the TX clock line, you would use rgmii-txid. If there is an extra long TX clock line, but not RX clock, you would use rgmii-rxid. You do not see this very often, but it does exist: arch/arm/boot/dts/nxp/ls/ls1021a-tsn.dts /* RGMII delays added via PCB traces */ &enet2 { phy-mode = "rgmii"; status = "okay"; Andrew