Marcus Folkesson

Embedded Linux Artist

Working on U-boot from Yocto (iMX8)

Working on U-boot from Yocto (iMX8) I have been asked a couple of times how to quickly make changes for U-Boot in Yocto. Those who asked have used to rebuild and flash an entire image each time, which takes an unnecessarily which is not a fast procedure. To rebuild U-Boot is`nt significantly different from any other recipe, but one difference is that imx-mkimage must also be built to generate a bootable image.

Skip flashing unused blocks with UUU

Skip flashing unused blocks with UUU TL;DR: UUU does now (or will shortly) support blockmaps for flashing images. Use it. It will shorten your flashing time *a lot.* It will soon be time to manufacture circuit boards for a project I'm currently working on. After manufacturing, it will need some firmware for sure, but how do we flash it in the most efficient way? The board is based on an i.

kas-container and QEMU

kas-container and QEMU KAS KAS [1] is a setup tool for bitbake based projects such as Yocto. There are many similiar alternatives out there and I've tried most of them, but my absolute favorite is KAS. In order to use KAS, you have to setup a YAML file to contain information about your machine, distribution, meta layers and local configuration. Here is a small example configuration copied from the KAS documentation:


meta-readonly-rootfs-overlay meta-readonly-rootfs-overlay [1] is a meta layer for the Yocto project [2] originally written by Claudius Heine. I took over the maintainership in May 2022 to keep it updated with recent Yocto releases and keep add functionality. I've implemented it in a couple of industrial products so far and think it needs some extra attention as I find it so useful. Why does this exists? Having a read-only root file system is useful for many scenarios: