Hey! I am having problems with hdmi display on khadas vim3l. For some reason, the display after starting the system shows only a black screen, but before everything worked fine. I am using ubuntu server 20.04 image with linux kernel 5.16rc-2. Changing the hdmi resolution configuration in the /boot/env.txt file also does not work. I have a 7 inch display with a resolution of 1024x600 (The display menu says 1024x768. What could be the reason? Thanks in advance 
@migmatore Modifying the configuration file only supports the 4.9 kernel, the main line is not supported. The main line is a standard framework, as long as the screen supports it, it will be automatically adapted.