How to get Native Portrait 4K LCD display working on Xavier NX

I’ve seen folks say that the Jetson L4T release doesn’t have built in support for native portrait displays. I need to get a native portrait 4k (3840x2400) display to work with the Jetson Xavier NX processor. I’ve seen posted instructions to patch the hdmi2.0.c file by changing the line:

if (mode->xres > 4096 || mode->yres > 2160)

to:

if ((mode->xres > 4096 || mode->yres > 2160) && (mode->xres > 2160 || mode->yres > 4096))

This should allow the portrait 4k resolution.

My question is: Does this require rebuilding the kernel or is it possible to rebuild a loadable module?

If so, is there a step-by-step guide to rebuild the kernel on the Jetson Xavier NX (vs. cross-compiling on a separate machine)?

Thanks,
David

The l4t developer guide has the steps to build kernel on host.

https://docs.nvidia.com/jetson/l4t/index.html#page/Tegra%20Linux%20Driver%20Package%20Development%20Guide/kernel_custom.html#wwpID0E06C0HA

You can download the source from our download center.