FORLX-3P-FET6254-C: AM62XX Debian desktop display

Part Number: FORLX-3P-FET6254-C

Tool/software:

I am implementing the desktop display function on the official Debian file system, I use lightdm+xfuce, and the effect is shown in the figure below.The background color is not displayed properly .

When I turn off the GPU in the device tree, the background shows up normally

Whether the problem can be resolved if the GPU function is enabled