If eTSEC1 is required in RGMII mode then the POR configuration pins should be set to {EC_MDC,TSEC1_TXD0,TSEC1_TXD7} = {010} and if eTSEC3 is required in RGMII mode then {UART_RTS0,UART_RTS1,TSEC_1588_ALARM_OUT2} = {101}
As all above signals default POR value is 1, you have to specify the signals that should be externally pull-down through a resistor when ever logic zero is required