Can the dedicated BREFCLK pins be routed to the fabric or only to the BREFCLKPIN and BREFCLKNIN pins of the RocketIO X (GT10) blocks?
The BREFCLKPIN pin can be routed to the fabric like all other I/O. The BREFCLKNIN pin does not have a fabric connection.
There are two situations that pertain to this connection:
1. If a MGT is instantiated on the same side as the BREFCLK pins, connections to a DCM, BUFG or the fabric from the BREFCLKPIN pin will be handled automatically by the tools.
There should NOT be an IBUFGDS or IBUFDS in the path from the BREFCLKPIN pin to the DCM, BUFG or fabric connection. It should be a direct connection from the pin.
2. If the MGT is not instantiated, the tools will NOT automatically route BREFCLKPIN to a DCM, BUFG or to the fabric. In that case, the BRECLKPIN has to be manually routed to the BUFG, DCM or fabric manually.