ID:20521 The input refclk of IOPLL <IOPLL instance name> is driven by an illegal source: <Refclk source name>. An IOPLL refclk's source must be either another IOPLL or a dedicated refclk input pin.

CAUSE: The input refclk of IOPLL %1!s! is driven by an illegal source: %2!s!.

ACTION: Connect the IOPLL refclk to either another IOPLL ouput or a dedicated input pin.