Using manufacturer-provided Orin NX device tree files with Yocto

[dstodev]

Hello!

I'm new to using Yocto, and have been working to build a simple, minimal Poky distro for an ASUS PE1100N development board.

This board uses an Nvidia Orin NX SoM.

Here's what I have so far.
(The repo README has more context and information)

I found that my approach "works", but it does not seem stable--a recent PR in meta-tegra required me to add a new recipe to continue supporting my approach.

Because I had to update my approach after a small change relating to the device tree, I'm not confident that I'm installing them the right way. I found this discussion recommending to install them directly by listing them in SRC_URI, but I'm not experienced enough with device trees or Yocto to understand how to apply this advice.

What is the recommended approach for using pre-existing device tree files?

[madisongh]

I took a quick look, and it appears OK, more or less - might be a bit of overkill, but without doing a side-by-side comparison of the vendor's files vs. NVIDIA's, it might be hard to pick out the exact files to install. It is somewhat confusing, since there are different device tree files used for the kernel, the UEFI bootloader, and various bits of the early-stage boot firmware.

For the kernel device trees, you could set PREFERRED_PROVIDER_virtual/dtb in your machine configuration to point to a recipe where you provide those DTB files, rather than using a bbappend to add them in with the rest of the NVIDIA-provided device trees. You might miss out on some DTB overlays built out of the NVIDIA collection, but you may not need them; if you do, you could have your recipe depend/rdepend on the nvidia-kernel-oot-dtb recipe.