Building QSMP/TXMP Series

Our layer provides a setup-environment script that simplifies the setup for our machines.

To use the script, the name of the specific machine to be built for needs to be specified, as well as the desired graphical backend. The script sets up a directory and the configuration files for the specified machine and backend. It also adds our layer to the bblayers.conf file, and configures the sstate-cache for you.

There are different configurations you can choose from.

  • DISTRO configurations:
DISTRO= Description
karo-minimal Ka-Ro Linux Distro with minimal read-only rootfs
karo-wayland Ka-Ro Linux Distro with wayland backend
karo-x11 Ka-Ro Linux Distro with X11 support
  • Possible MACHINE configurations:
STM32MP1 Processors

Use this command to setup your build directory (specify the distro, machine, and the build directory):

  • General Example:
DISTRO=<distro> MACHINE=<machine> source setup-environment <build-dir>

When the script has run, your current directory should have changed to the <build-dir> you chose before.

  • Specific Example (e.g. QSMP-1570):
DISTRO=karo-minimal MACHINE=qsmp-1570 source setup-environment build-qsmp-1570
  • Returning to existing build:

You can return to an already setup build directory by running:

source setup-environment <build-dir>

Building the Image


The setup-environment provided by the BSP already sets up a SSTATE CACHE to speedup the build process.
For more about sstate caches see Enable sstate cache 1.

Here are (some of) the different images (and packages) that can be build:

Image Description DISTRO= (required) Provided by layer
Official Ka-Ro BSP images
karo-image-minimal Image with minimal read-only rootfs karo-minimal meta-karo-distro
karo-image-base Image with minimal rootfs and udev instead of mdev karo-base meta-karo-distro
karo-image-weston Image with basic weston desktop, graphics accelerated karo-wayland meta-karo-distro
karo-image-qt5 Image with basic weston desktop and QT5. To use it wit QT-Creator see QT5 karo-wayland meta-karo-distro
karo-image-x11 Image with X11 support karo-x11 meta-karo-distro
Ka-Ro packages images
u-boot-karo U-Boot flashable binary N/A (any) meta-karo
linux-karo Linux Kernel and specified .dtb files only N/A (any) meta-karo
General Yocto / OE images
core-image-minimal See here @ OpenEmbedded Layer Index N/A (any) Poky

OpenEmbedded Layer Index

OpenEmbedded Layer Index for Recipes


Build the kernel image with the following command inside your <build-dir>.

bitbake linux-karo

Build the karo-image-minimal with the following command inside your <build-dir>.

bitbake karo-image-minimal

Getting the SDK

To build the SDK of a certain image run inside your <build-dir>:

bitbake <image> -c populate_sdk

Image Deployment

After a build is complete, the created image resides in the tmp/deploy/images/<machine> sub-directory. An image is, for the most part, specific to the machine set in the environment setup. Each image build creates different files.

The following files are created for Ka-Ro QSMP/TXMP modules when running karo-image-minimal:

Filename Content Module Type
flashlayouts_*/*.tsv FlashLayout File for STM32CubeProgrammer eMMC
uImage-<version>-<machine> Kernel uImage any
modules-<machine>.tgz Kernel modules any
<image>-<machine>.tar.{bz2|gz} RFS (bzip2/gzip) tar any
<image>-<machine>.ext4 RFS ext4 filesystem image eMMC
<image>-<machine>.ubi RFS ubi filesystem image NAND
u-boot* U-Boot files eMMC
*.dtb Device Tree Blob any


To continue with these images use STM32CubeProgrammer or TFTP boot.


See what you can do with Yocto built Images at Mainline BSP. If you compiled karo-image-qt5 check out QT5.