It is possible to do UHD (3840x2160P) using this chip by being careful to stay under the maximum HDMI dot clock.
Using CustomModeApp:
Front Porch H=48 V=3
Back Porch H=80 V=23
Sync Width H=32 V=5
Active H=3840 V=2160
Scan Rate V=25
It relies on the screen supporting 24Hz refresh rates as most UHD screens will. 24Hz is used by Blue-ray in film mode.
Dot Clock for these HDMI settings is 221MHz which is below the hardware maximum of 225MHz
