You may encounter this fitter error for Intel® Stratix® V GX or Stratix® V GT devices if you instantiate more than one instance of transceiver Reconfiguration Controller IP in the same half-side of the device and they use different mgmt_clk_clk input sources.
The fitting error is due to an incorrect connection to the physical transceiver calibration blocks. There is a single physical Calibration Block in each quadrant of the device, controlled by the transceiver Reconfiguration Controller IP.
Transceiver Reconfiguration Controllers with a Calibration Block must have the same mgmt_clk_clk source.
Please refer to the "Calibration Block Boundary" chapter of the Intel® Stratix® V GX handbook. This may be found in the "Transceiver Architecture in Stratix V Devices" volume.