Custom Modifications (device tree file)


I just have a question as to what is the best way to go about something. We have a system based off the beaglebone black but with a custom cape. We need to basically provide a custom DTB file to add in the additional hardware, modify uEnv to use this DTB and possibly add a few modules. From what i have read there are 2 ways to do this:

1 - Download base BBB image and update the files necessary during provisioning
2 - Build a custom Yocto build with the necessary changes and use the cli to put the config in

The problem i see with 2 is that we will be unable to update the systems from the interface because it does not support updating custom images so once in the field we are stuck with that image. Option 1 seems like it may be the better option because we could update, but would updating then cause the custom DTB and such to be removed when a system update is performed?

Is there something I am missing here? Is there some simple way i can add or modify files such as DTB and uEnv.txt from the interface or some other way on all devices?


Hi. Is the dtb source shareable? I think we may be able to add it to our image.
What other modules would you need?

@shaunmulligan wasn’t there a discussion on getting the supervisor to modify uboot uEnv.txt files just like it does for config.txt in rpi’s case?

Hi floion,

Sorry for the delay, yes we should be able to share the dtb and any modules. What is needed is not finalized at this point, I was just trying to figure out what the wisest direction would be for us to take. Our cape essentially just contains LEDs and several different communication ICs, such as wl1837, RS-485, Ethernet Switch, etc. and I may not even need to add any modules because I think they may already exist i just know it might be a possibility. So I might just need to put in an appropriate dtb file. If you think it would be best to have you just add it to your image then we could provide it once completed, then we would just need a way to get uEnv.txt set to use the correct DTB.