Nice information, i'm already browse for this on Baidu for a years. Can HDMI output still work during flash/install?

[amican]

[wxalriss]

ah it's a pity that, there are no any source code for HDMI in Device Tree Source of hi3798x SoC SDK.
if you finished compiling the source, burned images to eMMC, then boot, you'll get an error when loaded hi_vou.ko