VOXL 2 Kernel Build Guide
Table of contents
Overview
The VOXL 2 kernel comes from here: https://git.codelinaro.org/clo/la/kernel/msm-4.19
We started with the RB5 development kit and slowly updated the device tree and kernel to work on VOXL2 and VOXL2 Mini.
The aim of this guide is to show you how to build a new kernel for VOXL 2 and VOXL 2 mini and modify it.
Build Components
We’re trying to adhere to bitbake standards, but likely have some inconsistencies with our recipes… Feel free to offer suggestions if things are bugging you or submit PRs!
Setup Guide
Requirements
- git
- Docker
- the more cores the better if you want to build quickly…
Build Docker
We use “build dockers” all over the place to easily share build environments and use in our CI pipelines.
This step is optional, with the alternative being you look at the Dockerfile for the requirements for the build machine.
git clone -b qrb5165-ubun1.0-14.1a https://gitlab.com/voxl-public/system-image-build/qrb5165-kernel-build-docker
cd qrb5165-kernel-build-docker
./docker-build-image.sh
...
Step 28/28 : RUN export PATH=$PATH:/usr/local/go/bin
---> Running in 865ac9837af2
Removing intermediate container 865ac9837af2
---> 83b19199b7b5
Successfully built 83b19199b7b5
Successfully tagged qrb5165-kernel-build:qrb5165-ubun1.0-14.1a
Run Build Docker
Now that we have the docker image created (use docker image ls to see), we can run an instance of this using a helper script:
./docker-run-image.sh
To run a command as administrator (user "root"), use "sudo <command>".
See "man sudo_root" for details.
user@f3c06dd0167d:~$
Now you are in the chroot’d environment, and you don’t need to muddy your system with tools.
Build Guide
First Time Use (Part 1: Sync)
We have to synchronize with the https://git.codelinaro.org/clo as well as the various ModalAI open source components:
WARNING: This sync command takes some time (10 minutes?) before progressing…
./qrb5165-sync.sh
...
repo has been initialized in /home/user/build_mount/lu.um.1.2.1/apps_proc
Now we have the source code needed.
First Time Use (Part 1: Patch)
Apply patches found in the patches directory.
This is done to pull in VOXL 2 customizations and fix errors that are outside the scope of the product but needed to complete the build (e.g. build system fixes).
To apply the patches, run the following:
./qrb5165-patch.sh
Build
Now, you can build for VOXL 2, which is the M0054 machine. If building for RB5 Flight, you will use the M0052 machine.
./qrb5165-build.sh -m M0054
Artifacts
The kernel image is qti-ubuntu-robotics-image-m0054-boot.img and lives inside the build docker at:
/home/user/build_mount/lu.um.1.2.1/apps_proc/build-qti-distro-ubuntu-fullstack-debug/tmp-glibc/deploy/images/m0054/qti-ubuntu-robotics-image-m0054-boot.img
After you exit the build docker, it will be in your current directory in workspace, for example:
-la workspace/lu.um.1.2.1/apps_proc/build-qti-distro-ubuntu-fullstack-debug/tmp-glibc/deploy/images/m0054/
total 414500
drwxr-xr-x 2 modalai modalai 4096 May 3 15:18 .
drwxr-xr-x 3 modalai modalai 4096 May 3 15:09 ..
-rw-r--r-- 2 modalai modalai 21387346 May 3 15:09 Image.gz
-rw-r--r-- 1 modalai modalai 21393408 May 3 15:18 qti-ubuntu-robotics-image-m0054-boot.img
-rw-r--r-- 2 modalai modalai 5859250 May 3 15:09 System.map
-rw-r--r-- 2 modalai modalai 375915296 May 3 15:09 vmlinux
Flashing Guide
Test
You can boot the new kernel without flashing it.
First, check out the current version:
adb shell uname -a
Linux qrb5165-rb5 4.19.125 #1 SMP PREEMPT Fri Apr 15 16:54:55 UTC 2022 aarch64 aarch64 aarch64 GNU/Linux
Now, run the following:
adb reboot bootloader
fastboot boot qti-ubuntu-robotics-image-m0054-boot.img
adb wait-for-device
Now, check the new version:
adb shell uname -a
Linux qrb5165-rb5 4.19.125 #1 SMP PREEMPT Tue May 3 22:06:09 UTC 2022 aarch64 aarch64 aarch64 GNU/Linux
Flash
If testing worked above, you can now flash it:
adb reboot bootloader
fastboot flash boot qti-ubuntu-robotics-image-m0054-boot.img
adb wait-for-device
Developer Topics
How to Rebuild
You don’t need to re-sync and patch, just run and build. For example, starting back on the host machine (outside docker):
./docker-run-image.sh
To run a command as administrator (user "root"), use "sudo <command>".
See "man sudo_root" for details.
user@11dbde7bdab7:~$
user@11dbde7bdab7:~$ ls build_mount/lu.um.1.2.1/apps_proc/poky/
bitbake meta-openembedded meta-qti-audio meta-qti-core meta-qti-ml meta-qti-sepolicy meta-selftest meta-voxl2-bsp qti-conf README.qemu
documentation meta-poky meta-qti-bsp meta-qti-data meta-qti-qmmf meta-qti-ss-mgr meta-selinux meta-webkit README.hardware scripts
LICENSE meta-qti-adk meta-qti-bt meta-qti-display meta-qti-robotics meta-qti-ubuntu meta-skeleton meta-yocto-bsp README.LSB
meta meta-qti-aosphal-adaptation meta-qti-camera meta-qti-gst meta-qti-security meta-qti-video meta-voxl2 oe-init-build-env README.poky
Shown above, all the source is still there.
You can edit files, and the build again!
./qrb5165-build.sh
How to Enable In Tree Driver (Example)
See: https://gitlab.com/voxl-public/system-image-build/meta-voxl2-bsp/-/tree/qrb5165-ubun1.0-14.1a/recipes-kernel/linux-msm
For example, for M0054 (VOXL 2):
Enable smsc95xx using CONFIG_USB_NET_SMSC95XX
In:
apps_proc/poky/meta-voxl2-bsp/recipes-kernel/linux-msm/files/m005x.cfg
We can enable by adding CONFIG_USB_NET_SMSC95XX=y to the m005x.cfg file.
Now, you can build again:
./qrb5165-build.sh -m M0054
Note: to rebuild, clean out the existing build:
./qrb5165-clean.sh
# this time, for M0104, as example
./qrb5165-build.sh -m M0104
Flash following procedures above. We can check for the flag before the update:
voxl2:/$ zcat /proc/config.gz | grep CONFIG_USB_NET_SMSC95XX
# CONFIG_USB_NET_SMSC95XX is not set
And then after updating:
voxl2:/$ zcat /proc/config.gz | grep CONFIG_USB_NET_SMSC95XX
CONFIG_USB_NET_SMSC95XX=y