[Elias] made a custom driver board that takes an HDMI input and displays it on a very tiny, high-resolution display from a cell phone. The display used is the same as what comes stock in the HTC ...

[twl] has a board that does just that ... [twl] is using a rather large FPGA to handle all the conversion from HDMI to the DSI the display understands. He’s using an Xilinx Spartan-6-SLX9 ...

Plugable releases USBC-7400H4 for multi-monitor setups with 4 HDMI outputs at 4K 60Hz. USBC-7400H4 features Power Delivery pass-through for laptop charging during use. Compact and bus-powered design ...

These ports are HDMI, DisplayPort, and USB-C ... This ensures that your external display is as future-proof as possible. USB-C specifications are in a rather confusing state at the moment ...