If you're preparing the partnership return, there is a check box in the General Information section of the 8825 input screen to toggle between passive/non-passive.

However I agree with @Strongsilence-CPA  that the determination is really at the partner level.  If someone else prepared the 1065 & 8825 they may have a partner for whom the rental is non-passive because they are also the farmer and it could be self-rental.  

Or it could be wrong, but if you didn't prepare it then there is nothing you really need to do as long as the partner you're working with is treating it correctly on their 1040.