ID:176184 Bidirectional pins <name> and <name> with pseudo-differential I/O standard must either use a differential input path or have the output buffer's output enable (OE) set to VCC along with a proper assignment

CAUSE: You used a bidirectional pin with pseudo-differential I/O standard. However, on the input path, the pins are not connected to the differential buffer.

ACTION: If you want to use such a configuration, make sure that the OE for output buffers is set to V_CC. Additionally, you need to use the assignment TREAT_BIDIR_AS_OUTPUT (if no fan-out exists on the input path) or XSTL_INPUT_ALLOW_SE_BUFFER (if input path has fan-outs) on at least one of the complementary differential pins.