I am using the DisplayPort 1.4 RX Subsystem v2.1 IP RX only example design based on a ZCU102 board.
I have replaced the 4K based EDID provided with a DisplayID extension using the LoadEDID function provided in xdprxss_rxonly.c.
However, the DisplayPort RX core is not able to train with an Intel GPU.
This DisplayID extension EDID has a total of 384 bytes (EDID of 3 blocks of 128 bytes).
This EDID modified DisplayPort 1.4 RX Subsystem v2.1 IP RX only example design works well with NVIDIA graphics source (GeForce GTX 760M).
However the same example design hangs when using an Intel HD graphics source (tested sources: Intel UHD Graphics 620, Intel HD Graphics 530).
This was verified using AUX logs.
What is the issue?
Intel and NVIDIA graphics sources have different command sequences provided on the AUX channel for EDID greater than 256 bytes.
If you believe you are running into this issue, please see the Answer Record below for a patch for Vivado 2019.1.