### Finite field q power computations

Hey there, i'm trying to make a fast computation algorithm using shift operations. I'm having a field GF(q) and a field GF(q^m) for some integer m and i have an element x \in GF(q^m). I want to represent x in a normal basis of the vectorspace GF(q^m) over GF(q), so that I can use shift operations for computing x^q^k fast. Are there any way of doing this ?