UPGRADE YOUR BROWSER

We have detected your current browser version is not the latest one. Xilinx.com uses the latest web technologies to bring you the best online experience possible. Please upgrade to a Xilinx.com supported browser:Chrome, Firefox, Internet Explorer 11, Safari. Thank you!

AR# 33724

11.3 EDK - WARNING:EDK - : mpmc_0 (mpmc) - Could not determine clock frequency on input

Description

When using an EDK design clocked by a dcm_module, one of the following warnings occur. How do I resolve this issue?

WARNING:EDK - : mpmc_0 (mpmc) - Could not determine clock frequency on input clock port MPMC_Clk0, not performing clock DRCs.

WARNING:EDK - : mpmc_0 (mpmc) - Could not determine clock frequency on input clock port MPMC_Clk_200Mhz, not performing clock DRCs.

Performing Clock DRCs...

INFO:EDK:1038 - Did not implement clock DRCs for parameter:

xps_ethernetlite_0:C_SPLB_CLK_PERIOD_PS. Top-level frequency could not be propagated to this IP. Please make sure that you have specified the frequency of the top-level clock port, and that the clocks are properly connected.

INFO:EDK:1038 - Did not implement clock DRCs for parameter:

xps_mch_emc_0:C_MCH_SPLB_CLK_PERIOD_PS. Top-level frequency could not be propagated to this IP. Please make sure that you have specified the frequency of the top-level clock port, and that the clocks are properly connected.

INFO:EDK:1038 - Did not implement clock DRCs for parameter:

mpmc_0:C_MPMC_CLK0_PERIOD_PS. Top-level frequency could not be propagated to this IP. Please make sure that you have specified the frequency of the top-level clock port, and that the clocks are properly connected.

INFO:EDK:1038 - Did not implement clock DRCs for parameter:

mpmc_0:C_MPMC_CLK_MEM_PERIOD_PS. Top-level frequency could not be propagated to this IP. Please make sure that you have specified the frequency of the top-level clock port, and that the clocks are properly connected.

INFO:EDK:783 - Clock frequency could not be propagated to the port: MPMC_Clk0 in IP: mpmc_0 - Clock Ratio DRC will not be performed.

Solution

This is caused by the dcm_module not propagating the FREQUENCY attribute on its CLKIN port to its output ports. Without the FREQUENCY tag, IP cores connected to the clock cannot determine their clock rate.

It is recommended to replace the dcm_module with the clock_generator core, which correctly propagates the FREQUENCY attribute to its output clocks.

AR# 33724
Date Created 10/28/2009
Last Updated 12/15/2012
Status Active
Type General Article