About Vulkan and Future of High Performance Computing
Towards a heterogeneous & parallel computing architecture
OpenCL and Vulkan in the future would probably become the same thing. [1][2]
To utilise the power of Vulkan (and OpenCL) we do not have to code it our own, espectially for the purpose of deep learning.
By the way, some framework utilise OpenGL (Compute Shader API) as well, a higher level API.
Mali-G series GPU supports OpenCL 2.0 full profile.