Check the differ pin definition of driver and receiver, try to interchange pin and inv_pin for driver.
Thanks for your reply.
But the app note told me not to assign the model when I created the topology in LineSim, and it suggested to assign models using REF file after hyp file created.
So in that case, I can't really specify which is the DQS pin and which is DQS#.
And you will find the same problem if you run the demo case provided by Mentor.