Thank you for sharing more information on your goal here. I just wanted to make sure I understood where you were coming from.
I had tried resetting the value in a
device-tree-overlays-mainline_git.bbappendfile, but that was applied before it was set to includecolibri-imx7_vga-640x480_overlay.dtbo. I just flashed a version of my yocto built torizon derivative to verify. The device tree overlay gets applied if i setTEZI_EXTERNAL_KERNEL_DEVICETREE_BOOT = ""in thedevice-tree-overlays-mainline_git.bbappendfile. I did verify that thebbappendfile was being applied by checking the output ofbitbake-layers show-appends device-tree-overlays-mainline.
How exactly was your bbappend formatted? I believe this other post has an example on how to override that variable in the bbappend: Adding custom overlays to Yocto image - #6 by lucas_a.tx
On that note, is there a way to have a custom machine ‘inherit’ the settings from a base machine? I think I slowly understand how to override things as they are (using
.bbappendfiles and*-extra.conffiles. I have not created my own machine yet and am not sure what I’d need to set up for a new machine to work the same way as thecolibri-imx7-emmc.
We have an example of adding *-extra.conf files here: Custom meta layers, recipes and images in Yocto Project (hello-world examples) | Toradex Developer Center
It’s towards the end of the section I linked. The idea is not to create a brand new machine config. But, rather create an extra config file that gets included alongside the default machine config from us.
Best Regards,
Jeremias