how to include 64-bit multiplier using Qsys so that mulx hardware is enabled

[Altera_Forum]

In the produced .sopcinfo file I can manage to enable 32-bit multiplier hardware but I can't create a system where the mulx hardware is present. How can I do this? 

 Thanks

[Altera_Forum]

What version of Quartus are you using?  

 If you are using Quartus version before 14.1, the mulx hardware depends on your FPGA family that you are targeting, ie only Stratix family support mulx including Stratix II/III/IV and V.  Beyond 14.1 version, you can choose replace the Nios processor with the Nios II Gen 2 processor (newer processor), which you can enable mulx via the "Arithmetic Instructions" tab.