TX2 How to config two output of HDMI ?

Hi everyone ,I m a newer ,so I want more detail information about how to config the two output of HDMI .
1.how to config two output of HDMI device tree ,What is the file to reference ,what is the format to configure, and what part to configure。I need more specific details and can you give me the reference files,thanks a lot!
2.If I have changed the devicetree, do need to change the kernel file? and if so, how to modify the kernel source,and what is the specific file name.thank you very much!

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