def METHOD_NAME(self, fragment):
    LatticeECP5Platform.METHOD_NAME(self, fragment)
    self.add_period_constraint(self.lookup_request("clk100", loose=True), 1e9/100e6)
    self.add_period_constraint(self.lookup_request("eth_clocks:rx", 0, loose=True), 1e9/125e6)