ID:15504 Enable input port of PLL "<name>" must be driven by input pin

CAUSE: The enable input port (ena) of the specified enhanced or fast PLL is driven by something other than an input pin; however, an input pin must drive the ena port of the specified enhanced or fast PLL.

ACTION: Modify the design so an input pin drives the ena port of the enhanced or fast PLL or so only one input pin drives the ena port of a different enhanced or fast PLL.