Why does the UHD-SDI GT wrapper fail to implement when selecting a multi-link configuration?
When instantiating a UHD-SDI _GT and selecting 2 for UHD-SDI GT Links, a second design_1_uhdsdi_gt_0_0_top instance is never instantiated.
This is shown in the screenshot below.
This is a known issue that occurs when a users tries to implement the multi-link configuration of the UHD-SDI GT Core.
This issue has been fixed in Vivado 2018.2 and later.
Xilinx recommends updating to the latest version of the IP.