The phrase you want is "can we rock it?" "Up there" is the location.
I'd interpret it as meaning "have a party". The person is asking if it's isolated enough up there to not be disturbed if they have a party.
Alternately, "rock it up" may mean make it cool, make it "rock n roll"... if the location is not cool enough.
A third possibility: taking out the "it", you have "can we rock up there", "rock up" meaning to arrive. Eg. "When's old mate gonna rock up?" (and at this point I actually check 一's link)