When using the DisplayPort TX Subsystem 2.0 (Rev. 2) to send the PRBS-7 sequence, sometimes (not all of the time) the transmitted PRBS-7 sequence is not properly aligned for the PRBS-7 pattern.
The User test procedure is as follows:
This issue occurs in the LogiCORE DisplayPort TX Subsystem v2.0 (Rev. 2) through v2.0 (Rev. 5).
This issue will be fixed in Vivado 2017.3.