Mixing OpenCL kernel with VHDL Netlists

You could add it to the board support package (the hardware your kernel gets added to automatically). You would have to modify the board files so that the kernel compiler knows your extra hardware is present but if your VGA block exposes an Avalon-ST sink port then you can have a kernel write the data directly into it using channels. I would become very familiar with board support packages and channels before attempting this though.

So the idea is not that you edit the system that the OpenCL compiler generates, but rather you edit the system the compiler plugs the kernel into. If you send me a private message with your email address I can send you a 13.0 or 13.1 (I forget which version) Nallatech BSP I hacked up to add a counter that streams an incrementing count value that my kernel just reads and spits out to memory that I verify on the host side. You would be just moving data in the opposite direction.