220.127.116.11. Timing Closure Guidelines
However, if the I/O PLL drives the clocks of the GPIO input registers (simple register or DDIO mode), you can set the compensation mode to source synchronous mode. The Fitter automatically configures the I/O PLL to improve the setup and hold slack for the input I/O timing analysis.
For the GPIO output and output enable registers, you can add delay to the output data and clock using the output and output enable delay chains.
- If you observe setup time violation, you can increase the output clock delay chain setting.
- If you observe hold time violation, you can increase the output data delay chain setting.