Update Jetson TX2 kernel and DTB files

    JetsonTX2 is being studied with the goal of developing an image acquisition module. According to the L4T document description, the board's built-in camera module dtsi file was rewritten, and the kernel was recompiled on the board to generate the Image file and the dts folder. So far everything went well, and after updating the kernel and dtb according to the documentation, unexpected problems occurred. The kernel update method described in the document is to copy the Image to the board's / boot directory and overwrite the file with the same name, and copy the dtb file in the dts folder to the / boot / dtb directory to overwrite the file with the same name. Load the new kernel. After restarting, use the uname -a command to test the kernel information. It was found that the running kernel was indeed compiled just now. However, the device node that I developed was not found under / proc / device-tree /.
    First, I suspected that the modified dtsi file was not compiled into the dtb file. Use the dtc tool to export the .dts file from the .dtb file, view the .dts with a text editor, and find that the modified content has been compiled in. Check the countless operation steps against the document and confirm that the operation is correct. Toss for a long time to no avail, but desperately gave up the idea of compiling and updating on the board. Recompile the tx2 kernel on the pc, copy the new kernel and dtb files to the location where the JetPack installation directory stores the kernel image and dtb files, flash the machine, restart the board, and the device node added to dtsi finally appeared!
The command to flash the kernel on the PC is:
./flash.sh -k kernel jetson-tx2 mmcblk0p1
The command to flash the dtb file is:
./flash.sh -k kernel-dtb jetson-tx2 mmcblk0p1
    Updating the dtb file seems to involve uboot. It is not enough to update the / boot folder on the board, you must use a pc to flash the machine.