MACHXO3/MACHXO2: What can cause EFB to malfunction in hardware?
Description:
When EFB malfunctions in hardware it is best to check if the EFB is instantiated properly and not optimized.
Solution:
To workaround this issue, If it is certain that EFB is not optimized, please make sure that GSR is disabled. When GSR is enabled, it is assigned to a random net connected with the EFB that causes failure in operation. Lattice recommend to disable GSR when EFB is being used.