Currently it is not supported , but you can develop the custom blocks depending on requirement.
As device driver development is applicable for all targets, I am providing links for few other targets as well
IO Device builder App - IO Device Builder App - MATLAB & Simulink - MathWorks India
Another way could be utilising the External code Import blocks: Embedded Coder — Blocks
An example for above mentioned method, where System Initialize and Model Source blocks are used to implement HRTIMER peripheral:
