The HPD signal can operate in either a 3.3V or 2.5V I/O bank. By definition in the standard, it is a 3.3V signal.
For AMD Kintex™ 7 devices supporting HR IO banks, use the following constraints:
set_property IOSTANDARD LVCMOS25 [get_ports hpd];For AMD Virtex™ 7 devices supporting HP I/O banks, use the following constraints:
set_property IOSTANDARD LVCMOS18 [get_ports hpd];Board design and connectivity should follow DisplayPort Standard recommendations with correct level shifting.