Tweaking Base Overlay to Support 16 bit Color Depth Gray Scale Image

I am working with the base overlay and want to tweak it so that it support 16 bit gray scale image both at the input and the output of the hdmi. Is this setup possible with the base overlay and how am I going about to do it? Any recommendation will be helpful.

So I remove the color convert on both the input and output hdmi IPs and the pixel packer and unpacker too. I configure all the IPs (VDMA, register slice, pixel reorder, HDMI receiver and transmitter subsystem) to accommodate 16bit color depth. The pipeline line works fine like this but when I do a loopback setup (hdmi in connected to hdmi out on the ZCU104 board), the data received is blank as compare to the data being transmitted. The mode of the hdmi in showed 24 bpp even though I configured the hdmi out mode to be 48 bpp.