Vijayan Krishnan

10/23/2021, 9:38 AM
Hi, I am facing issue while running yosys synthesis with latest openroad flow scripts for my ethernet design. Error shown below: 41. Executing TECHMAP pass (map to technology primitives). 41.1. Executing Verilog-2005 frontend: ./platforms/asap7/yoSys/cells_latch.v 41.2. Continuing TECHMAP pass. 42. Executing DFFLIBMAP pass (mapping DFF cells to sequential cells from liberty file). 42.1. Executing DFFLEGALIZE pass (convert FFs to types supported by the target). ERROR: FF eth_top.$auto$$26021 (type $_DFF_PP0_) cannot be legalized: dffs with async set or reset are not supported Command exited with non-zero status 1 Any suggestion how to fix it?

Indira Iyer

10/23/2021, 9:38 PM
As the error says the problem is with the asynchronous dff inputs. Try this: