In Vivado, when I try to route a design in an HDIO block on an ES1 ZU9EG device, the following warning can occur:
The tools seem unable to route both to an IOB Flip-flop and Fabric.
What does this warning mean?
The HDIO block for the ES1 ZU9EG device lacks the ability to register in the IOB and route directly to fabric due to a device limitation.
This limitation has been removed to accommodate design migration through a design change to the IOB.
ES2 and newer versions of the ZU9EG do not have this limitation provided that the 2016.1 (or newer) software tools are leveraged.
This issue only impacts HDIO in the ES1 versions of the ZU9EG found in the Zynq UltraScale + family.