Critical Issue
Description
This problem affects DDR2 and DDR3 products.
In version 11.1 SP1, a Fitter error occurs when Read DQS Tracking is enabled.
Resolution
The workaround for this issue is to add the following in lines
1005-1006 of altdq_dqs2_stratixv.sv :
always @(negedge dqs_disable_int)
dqs_ff <= dqsin;