Cache timing on ARM processor

Question

i need to implement AES algorithm on a smartphone with ARM Cortex A-15 processor(Samsung Galaxy Note 3, etc) and need to observe and save cache timings for each process, round. How do I go about it? To be precise, I need to observe time taken by the processor to run each round of the AES per plaintext - key pair. I am trying to find the practicability of timing attacks in smartphones(focus on Bernstein's modified attacks but will see feasibility of both trace driven and access driven cache attacks). It is for academic purposes. I understand the architecture of the processor used. Problem lies in the assembly programming - not getting the right code- as well as how to load this program onto the smartphone.