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Semantic MediaWiki
There are 1 incomplete or pending task to finish installation of Semantic MediaWiki. An administrator or user with sufficient rights can complete it. This should be done before adding new data to avoid inconsistencies.1. Overview[edit source]
This stage explains how modify, rebuild and reload the Linux® kernel.
You will first be guided to install the Linux® kernel source code in the Developer Package directory. Then step by step you will execute procedures to modify, rebuild and reload the Linux® kernel.
2. Download the the Linux® kernel source code[edit source]
The software package is provided AS IS, and by downloading it, you agree to be bound to the terms of the software license agreement (SLA). The detailed content licenses can be found here.
For ecosystem release v2.1.0 
[edit source]
- Download the STM32MP15-Ecosystem-v2.1.0 Developer Package Sources to the following directory:
$HOME/STM32MPU_workspace/STM32MP15-Ecosystem-v2.1.0/Developer-Package - Uncompress the tarball file to get the Linux® kernel tarball, the ST patches and the ST configuration fragments
cd $HOME/STM32MPU_workspace/STM32MP15-Ecosystem-v2.1.0/Developer-Package tar xvf en.SOURCES-kernel-stm32mp1-openstlinux-5-4-dunfell-mp1-20-11-12.tar.xz
For ecosystem release v2.0.0 [edit source]
- Download the STM32MP15-Ecosystem-v2.0.0 Developer Package Sources to the following directory:
$HOME/STM32MPU_workspace/STM32MP15-Ecosystem-v2.0.0/Developer-Package - Uncompress the tarball file to get the Linux® kernel tarball, the ST patches and the ST configuration fragments
cd $HOME/STM32MPU_workspace/STM32MP15-Ecosystem-v2.0.0/Developer-Package tar xvf en.SOURCES-kernel-stm32mp1-openstlinux-5-4-dunfell-mp1-20-06-24.tar.xz
3. Prepare the Linux® kernel source code[edit source]
- Extract the Linux® kernel source
For ecosystem release v2.1.0
- Apply the ST patches
cd linux-5.4.56 /* For ecosystem release v2.1.0
- Apply fragments
make ARCH=arm multi_v7_defconfig "fragment*.config" for f in `ls -1 ../fragment*.config`; do scripts/kconfig/merge_config.sh -m -r .config $f; done yes '' | make ARCH=arm oldconfig
4. Build the Linux® kernel source code for the first time[edit source]
- Build kernel images (uImage and vmlinux) and device tree (dtbs)
make ARCH=arm uImage vmlinux dtbs LOADADDR=0xC2000040
- Build kernel module
make ARCH=arm modules
- Generate output build artifacts
mkdir -p $PWD/install_artifact/ make ARCH=arm INSTALL_MOD_PATH="$PWD/install_artifact" modules_install
5. Deploy the Linux® kernel on the board[edit source]
5.1. Push the Linux® kernel into the board[edit source]
scp arch/arm/boot/uImage root@<board ip address>:/boot
5.2. Push the devicetree into the board[edit source]
scp arch/arm/boot/dts/stm32mp157*.dtb root@<board ip address>:/boot
5.3. Push the kernel modules into the board[edit source]
- Remove the link created inside the install_artifact/lib/modules/<kernel version> directory
For ecosystem release v2.1.0
- Optionally, strip kernel modules (to reduce the size of each kernel modules)
find install_artifact/ -name "*.ko" | xargs $STRIP --strip-debug --remove-section=.comment --remove-section=.note --preserve-dates
- Copy Kernel modules
scp -r install_artifact/lib/modules/* root@<ip of board>:/lib/modules
- Using the Linux console, re-generate the list of module dependencies (modules.dep) and the list of symbols provided by modules (modules.symbols)
/sbin/depmod -a
- Synchronize data on disk with memory
sync
5.4. Reboot the board[edit source]
reboot
6. Modifying a built-in Linux kernel device driver[edit source]
This simple example adds unconditional log information when the display driver is probed.
- Using the Linux console, check that there is no log information when the display driver is probed
dmesg | grep -i stm_drm_platform_probe
- Go to the Linux® kernel source directory
For ecosystem release v2.1.0
- Edit the ./drivers/gpu/drm/stm/drv.c source file
- Add a log information in the stm_drm_platform_probe function as follow
static int stm_drm_platform_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct drm_device *ddev;
int ret;
[...]
DRM_INFO("Simple example - %s\n", __func__);
return 0;
[...]
}
- Save the file
- Rebuitd the Linux® kernel
make uImage LOADADDR=0xC2000040
- Update the Linux kernel image into board
scp arch/arm/boot/uImage root@<board ip address>:/boot
- Reboot the board
reboot
- Check that there is now log information when the display driver is probed
dmesg | grep -i stm_drm_platform_probe [ 2.764080] [drm] Simple example - stm_drm_platform_probe