Channel bonding is necessary for a multi-lane Aurora design. Channel bonding is performed by the transceiver and the required logic is present in the transceiver_wrapper module. Make sure that the channel bonding level and master and slave connections are correct. Check that the CLK_COR_MIN_LAT and CLK_COR_MAX_LAT attributes of the transceiver are set as recommended. See the Channel Bonding Procedure in the Aurora 8B/10B Protocol Specification v2.2 (SP002) [Ref 5] for channel_up assertion.