TS-7180 Kernel Compile Guide
This board has a 4.9 LTS kernel, the source for which is on github in embeddedTS/linux-4.9.y. Compiling the kernel requires an armhf toolchain.
Preparing to Build
We recommend building in a Debian environment, whether actual system (or VM) or a Docker container. Here are the instructions for each:
Building under Debian
Builds require several tools to be present your distribution. For Debian:
| WARNING: | This process may be broken for generic Debian; the commands for Ubuntu should be correct. |
su root
apt-get install curl git build-essential lzop u-boot-tools libncursesw5-dev
echo "deb http://emdebian.org/tools/debian buster main" > /etc/apt/sources.list.d/emdebian.list
curl http://emdebian.org/tools/debian/emdebian-toolchain-archive.key | apt-key add -
dpkg --add-architecture armhf
apt-get update
apt-get install crossbuild-essential-armhf
For Ubuntu:
sudo apt-get update
sudo apt-get install crossbuild-essential-armhf git build-essential lzop u-boot-tools libncursesw5-dev
Building under Docker
Debian only provides their cross compiler for their distribution. Our examples will set up a Docker for Debian to use for development. If using Debian 10 Buster directly, or through a VM then the docker usage can be skipped.
Create a file called "Dockerfile" with these contents:
FROM debian:buster
RUN dpkg --add-architecture armhf
RUN apt-get update && apt-get install -y \
autogen \
automake \
bash \
bc \
bison \
build-essential \
bzip2 \
ca-certificates \
ccache \
chrpath \
cpio \
curl \
diffstat \
fakeroot \
file \
flex \
gawk \
gcc-arm-linux-gnueabihf \
git \
gzip \
kmod \
libgpiod-dev:armhf \
libncursesw5-dev \
libssl-dev \
libtool \
locales \
lzop \
make \
multistrap \
ncurses-dev \
pkg-config \
python \
python3 \
python3-pip \
python3-pexpect \
qemu-user-static \
rsync \
socat \
runit \
texinfo \
u-boot-tools \
unzip \
vim \
wget \
xz-utils
# To make a more readable PS1 to show we are in the Docker
ENV debian_chroot debian_buster
RUN echo "PS1='\${debian_chroot}\\[\033[01;32m\\]@\\H\[\\033[00m\\]:\\[\\033[01;34m\\]\\w\\[\\033[00m\\]\\$ '" >> /etc/bash.bashrc
# Set up locales. Needed by yocto.
RUN sed -i -e 's/# en_US.UTF-8 UTF-8/en_US.UTF-8 UTF-8/' /etc/locale.gen && \
echo 'LANG="en_US.UTF-8"'>/etc/default/locale && \
dpkg-reconfigure --frontend=noninteractive locales && \
update-locale LANG=en_US.UTF-8
ENV LC_ALL en_US.UTF-8
ENV LANG en_US.UTF-8
ENV LANGUAGE en_US.UTF-8
In the same directory as the file named "Dockerfile" run:
docker build --tag armhf-buster-toolchain .
When this has finished the docker can be used with:
docker run --rm -it --volume $(pwd):/work armhf-buster-toolchain bash
This will map the current directory to /work.
At this point the Debian Docker is ready to compile armhf binaries. For example, create a hello world in your home folder at ~/hello.c
#include <stdio.h>
int main(){
printf("Hello World\n");
}
To compile this enter the docker with:
docker run -it --volume $(pwd):/work armhf-buster-toolchain bash
# Then from the docker:
cd /work/
arm-linux-gnueabihf-gcc hello.c -o hello
Check "file hello" to verify the binary type:
user@host:~/$ file hello hello: ELF 32-bit LSB pie executable, ARM, EABI5 version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-armhf.so.3, for GNU/Linux 3.2.0, BuildID[sha1]=8a8cee3341d3ef76ef6796f72d5722ae9d77c8ea, not stripped
This can also be used to develop against dynamic libraries from Debian. The armhf packages can be installed in the Docker. For example, to link against curl:
# Enter the Docker:
docker run -it --volume $(pwd):/work armhf-buster-toolchain bash
cd /work/
apt-get install libcurl4-openssl-dev:armhf
# Download curl's simple.c example
wget https://raw.githubusercontent.com/bagder/curl/master/docs/examples/simple.c
arm-linux-gnueabihf-gcc simple.c -o simple -lcurl
The "simple" binary is now built for armhf and links dynamically to curl.
This will only retain the armhf libcurl package until the docker is exited. To make the changes permanent, add the package to the Dockerfile and rerun:
docker build --tag armhf-buster-toolchain .
Compiling the Kernel
Once your build environment is prepared:
git clone https://github.com/embeddedTS/linux-4.9.y
cd linux-4.9.y
git checkout master
## If you are using the 64-bit toolchain:
export CROSS_COMPILE=arm-linux-gnueabihf-
export ARCH=arm
export LOADADDR=0x80800000
make tsimx6ul_defconfig
## Make any changes in "make menuconfig" or driver modifications, then compile
make && make zImage && make modules
Installing the Kernel, Headers, or Modules
To install the headers and/or objects built above to a board, first create a tarball so you can copy it to removable media or another machine.
The following will install the kernel and modules to a temporary directory, and then pack them up in to a single tarball:
TEMPDIR=$(mktemp -d)
mkdir "${TEMPDIR}/boot/"
cp arch/arm/boot/zImage "${TEMPDIR}"/boot/zImage
cp arch/arm/boot/dts/imx6ul*ts*.dtb "${TEMPDIR}"/boot/
INSTALL_MOD_PATH="${TEMPDIR}" make modules_install
INSTALL_HDR_PATH="${TEMPDIR}" make headers_install
tar czf linux-tsimx6ul-"$(cat include/config/kernel.release)"-"$(date +"%Y%m%d")".tar.gz -C "${TEMPDIR}" .
rm -rf "${TEMPDIR}"
This will output a tarball with the kernel version and short git hash, as well as the date the tarball was created. For example: linux-tsimx6ul-v4.9.171-60-g01e2117e-20190823.tar.gz
This tarball can be directly unpacked to the root folder of a bootable media for the device. It is also possible to unpack it directly on a booted system, however we do not recommend doing so on an active deployed system without extensive testing.
# Unpack it to a mounted disk, this assumes the disk is mounted to "/mnt"
zcat linux-tsimx6ul...tar.gz | tar xh -C /mnt
# Unpack it to the root directory of a booted system
zcat linux-tsimx6ul...tar.gz | tar xh -C /
Troubleshooting
If you experience problems compiling the kernel with the compiler in your distribution, please try whichever of the below toolchains is appropriate for your architecture:
In the case of either toolchain you would run these commands to install them:
chmod a+x poky-*.sh
sudo ./poky-*.sh
5.10 Kernel Compile Guide
Although the TS-7180 is currently shipping with 4.9, a 5.10 kernel is available for testing on GitHub. See below for instructions on building and running it.
A compatible armhf cross compiler is needed for building the 5.10 kernel. We recommend using the cross compiler available in Debian distributions. It is also possible to use our Buildroot repository to build a compatible cross compiler.
Download and Configure
These steps assume a host Linux workstation with an appropriate cross compiler. While on most platforms the kernel can be downloaded, built, and installed all on the device, we recommend against this due to the amount of time, memory, and disk space that can be needed for a build.
Prerequisites
If using our instructions for using Docker to handle the cross compiler, then the Docker environment needs to be entered first:
# Create a place to store the kernel:
mkdir -p ~/Projects/tsimx6ul/kernel/
cd ~/Projects/tsimx6ul/kernel/
docker-debian-bookworm
If the Docker container is not being used, a number of host tools are required to be installed on the workstation:
# Install dependencies for kernel build
# The following command is for Ubuntu / Debian workstations. If using a different
# distribution, please consult distribution docs for the proper commands to install
# new packages/tools/libraries/etc.
apt-get install git fakeroot build-essential ncurses-dev xz-utils libssl-dev bc flex libelf-dev bison
| Note: | The above prerequisite libraries and tools may not be the complete list, depending on the workstation's distribution and age. It may be necessary to install additional packages to support kernel compilation. |
Download kernel repo on a host Linux workstation:
# Do a shallow clone of the sources
git clone --depth 1 -b linux-5.10.y https://github.com/embeddedTS/linux-lts
cd linux-lts/
git checkout add-ts7180-support
Configure environment variables needed for building. This specifies the architecture, the cross compiler that is being used, and to set up building the kernel modules for the WILC3000 Wi-Fi/BLE module:
export CROSS_COMPILE=arm-linux-gnueabihf- # This may be different if using a different compiler!
export ARCH=arm
export WILC=y
The WILC3000 Wi-Fi/BLE drivers are maintained and built externally out of the kernel tree. Clone this tree inside of the linux-lts/ directory (this is built later):
git clone https://github.com/embeddedTS/wilc3000-external-module/
Next, set the default configuration for this platform. Note that a minimal defconfig and a full-feature defconfig are available. The minimal defconfig contains options for supporting the device and a few common peripherals and technologies. While the full defconfig includes much more support for things like USB devices, a more broad range of netfilter/iptables filter module support, etc.
make tsimx6ul_defconfig
# The minimal defconfig can alternately be used with:
# make tsimx6ul_minimal_defconfig
Build and Install
| Note: | If using the Docker container to cross compile, be sure to exit the container after the build script below completes! The tarball will be located in the linux-lts/ folder that was created.
|
The following will build the kernel and modules, and install the kernel, modules, and headers to a folder and create a tarball from that. This tarball can be unpacked to bootable media, e.g. microSD, eMMC, USB, etc., to update an existing bootable disk.
The script below is most easily saved as a text file and run from the command line as a script. Most terminal emulators will accept the whole script copy/pasted in to the terminal. But it is also possible to copy paste each line of text in to a terminal. In any case, the following is an example of how to compile the kernel. The script or commands used can be modified as needed to suit a specific build pipeline.
The script assumes the following environment variables are set before it is run. See the above sections for what these variables should be set to for this specific platform.
ARCH- Used to indicate the target CPU architecture.
CROSS_COMPILE- Used to point to an appropriate cross toolchain for the target platform.
LOADADDR[Optional]- Used on some platforms to tell U-Boot where to load the file.
WILC[Optional]- Set to "y" to build and install the WILC3000 Wi-Fi/BLE external modules.
#!/bin/bash -e
# Always build zImage, most common. If LOADADDR is set, then uImage is also built
TARGETS="zImage"
if [ -n "${LOADADDR}" ]; then TARGETS+=" uImage"; fi
# Build the actual kernel, binary files, and loadable modules.
# Use as many CPUs to do this as possible.
make -j"$(nproc)" && make ${TARGETS} && make modules
# Create a temporary directory to install the kernel to in order to use that as a base directory for a tarball.
# Also creates a temporary file that is used as the tarball name.
TEMPDIR=$(mktemp -d)
TEMPFILE=$(mktemp)
mkdir "${TEMPDIR}/boot/"
# Adds "arch/arm/boot/" path prefix to each TARGET
cp $(for i in ${TARGETS}; do echo arch/arm/boot/$i; done) "${TEMPDIR}"/boot/
# Copy the full .config file to the target, this is optional and can be removed
cp .config "${TEMPDIR}"/boot/config
# Copy all of the generated FDT binary files to the target
cp arch/arm/boot/dts/*ts*.dtb "${TEMPDIR}"/boot/
# Install kernel modules to the target
INSTALL_MOD_PATH="${TEMPDIR}" make modules_install
# Install kernel headers to the target, this is optional in most cases and can be removed to save space on the target
make headers_install INSTALL_HDR_PATH="${TEMPDIR}"
# If WILC is set to "y", then build the external module for the WILC300 Wi-Fi/BLE device.
# Note that this expects the source to be available as a subfolder in the kernel. See the above sections
# for details on getting the driver source if it is used on this specific platform.
if [ "${WILC}" == "y" ]; then
CONFIG_WILC_SPI=m INSTALL_MOD_PATH="${TEMPDIR}" make M=./wilc3000-external-module modules modules_install
fi
# Use fakeroot to properly set permissions on the target folder as well as create a tarball from this.
fakeroot sh -c "chmod 755 ${TEMPDIR};
chown -R root:root ${TEMPDIR};
tar czf ${TEMPFILE}.tar.gz -C ${TEMPDIR} .";
# Create a final output tarball and cleanup all of the temporary files and folder.
cp ${TEMPFILE}.tar.gz embeddedTS-linux-lts-"$(date +"%Y%m%d")"-"$(git describe --abbrev=8 --dirty --always)".tar.gz
rm -rf "${TEMPDIR}" "${TEMPFILE}"
At this point, the tarball can be unpacked to a bootable media for the device. This can be done from a booted device, or by mounting removable media from a host Linux workstation. For example, if the root folder of the target filesystem to be updated is mounted to /mnt/, the following can be used to unpack the above tarball:
# Ensure the target filesystem is mounted to /mnt first!
# Extract kernel tarball to target filesystem,
tar xhf embeddedTS-linux-lts-*.tar.gz -C /mnt
| Note: | The h argument to tar is necessary on recent distributions that use paths with symlinks. Not using it can potentially render the whole filesystem no longer bootable.
|
This will correctly unpack the kernel, modules, and headers to the target filesystem which can then be booted as normal.