How to fix FRDM-IMx93 Linux Kernel BSP

This guide provides step-by-step instructions for setting up and applying necessary patches to the Linux kernel for the FRDM-IMX93 development board. The process involves cloning the required repositories, applying patches, and preparing the kernel for customization and compilation.

Prerequisites

Required Software:

A Linux-based operating system (Ubuntu/Debian recommended).
Git installed (sudo apt install git).

Yocto dependencies:

$ sudo apt install gawk wget git diffstat unzip texinfo gcc build-essential chrpath socat cpio python3 python3-pip python3-pexpect xz-utils debianutils iputils-ping python3-git python3-jinja2 python3-subunit zstd liblz4-tool file locales libacl1

Hardware:

FRDM-IMX93 Board
Sufficient storage space

1. Downloading the Repository

Start by downloading the necessary tools and repository. If the ~/bin folder does not already exist, create it:

$ mkdir ~/bin (this step may not be needed if the bin folder already exists)
$ curl https://storage.googleapis.com/git-repo-downloads/repo > ~/bin/repo
$ chmod a+x ~/bin/repo
$ export PATH=~/bin:$PATH

2. Compile the Yocto SDK:

$: mkdir Yocto_SDK
$: cd Yocto_SDK
$: repo init -u https://github.com/nxp-imx/imx-manifest -b imx-linux-scarthgap -m imx-6.6.36-2.1.0.xml
$: repo sync

$: MACHINE=imx93evk DISTRO=fsl-imx-xwayland source ./imx-setup-release.sh -b bld-xwayland
$: bitbake imx-image-full -c populate_sdk

Run the generated .sh file to install the SDK:

sudo ./fsl-imx-xwayland-glibc-x86_64-imx-image-full-armv8a-imx93evk-toolchain-6.6-scarthgap.sh

The final .sh file is located in:

bld-xwayland/tmp/deploy/sdk/

3. Creating the Working Directory

First, create a dedicated directory for the kernel setup and navigate into it:

$ mkdir FRDM-IMX93-Kernel 
$ cd  FRDM-IMX93-Kernel

4. Cloning the Kernel patches

Retrieve the necessary kernel patches from the NXP repository:

$ git clone https://github.com/nxp-imx-support/meta-imx-frdm.git -b lf-6.6.36-2.1.0

5. Cloning the Kernel Repository (linux-imx repository)

Clone the kernel source of Yocto SDK that you built earlier:

$ git clone https://github.com/nxp-imx/linux-imx.git -b lf-6.6.36-2.1.0

6. Applying Kernel Patches

Apply the necessary patches to the kernel:

$ cd linux-imx/

$ git apply ../meta-imx-frdm/meta-imx-bsp/recipes-kernel/linux/linux-imx/0001-gpio-pca953x-fix-pca953x_irq_bus_sync_unlock-race.patch

$ git apply ../meta-imx-frdm/meta-imx-bsp/recipes-kernel/linux/linux-imx/0002-arm64-dts-add-i.MX93-11x11-FRDM-basic-support.patch

$ git apply ../meta-imx-frdm/meta-imx-bsp/recipes-kernel/linux/linux-imx/0003-arm64-dts-add-imx93-11x11-frdm-mt9m114-dts.patch

$ git apply ../meta-imx-frdm/meta-imx-bsp/recipes-kernel/linux/linux-imx/0004-Add-DSI-Panel-for-imx93.patch

$ git apply ../meta-imx-frdm/meta-imx-bsp/recipes-kernel/linux/linux-imx/0005-Add-CTP-support-for-waveshare-panel.patch

$ git apply ../meta-imx-frdm/meta-imx-bsp/recipes-kernel/linux/linux-imx/0006-arm64-dts-add-imx93-11x11-frdm-tianma-wvga-panel-dts.patch

$ git apply ../meta-imx-frdm/meta-imx-bsp/recipes-kernel/linux/linux-imx/0007-arm64-dts-add-imx93-11x11-frdm-aud-hat-dts.patch

$ git apply ../meta-imx-frdm/meta-imx-bsp/recipes-kernel/linux/linux-imx/0008-arm64-dts-add-button-support.patch

$ git apply ../meta-imx-frdm/meta-imx-bsp/recipes-kernel/linux/linux-imx/0009-arm64-dts-add-imx93-11x11-frdm-ov5640-dts.patch

$ cd linux-imx/

$ git apply ../meta-imx-frdm/meta-imx-bsp/recipes-kernel/linux/linux-imx/0010-arm64-dts-add-imx93-11x11-frdm-ld.dts-for-lpm.patch

$ git apply ../meta-imx-frdm/meta-imx-bsp/recipes-kernel/linux/linux-imx/0011-arm64-dts-add-pwm-function-of-the-LED.patch

$ git apply ../meta-imx-frdm/meta-imx-bsp/recipes-kernel/linux/linux-imx/0012-arm64-dts-add-imx93-11x11-frdm-8mic.dts.patch

$ git apply ../meta-imx-frdm/meta-imx-bsp/recipes-kernel/linux/linux-imx/0013-arm64-dts-add-imx93-11x11-frdm-lpuart.dts.patch

7. Customizing the Device Tree

Device trees can be modified or created based on your hardware setup.

Device Tree Locations:

arch/arm64/boot/dts/freescale/

If you create a new device tree, add it to the respective Makefile:

arch/arm64/boot/dts/freescale/Makefile

8. Setting Up the Cross-Compilation Environment

To prepare for kernel compilation, source the environment setup script. Assuming the Yocto SDK is installed in /opt, run:

EXAMPLE:

$ source /opt/fsl-imx-xwayland/6.6-scarthgap/environment-setup-armv8a-poky-linux

9. Configuring the Kernel

Make configuration adjustments as needed in the file:

arch/arm64/configs/imx_v8_defconfig

Use the appropriate configuration command:

$: make imx_v8_defconfig

10. Compiling Device Trees Only

To compile only the device tree files, run:

$: make dtbs

11. Compiling the Kernel

Finally, compile the kernel image using:

$ make -j $(nproc)

The resulting kernel image will be located in:

arch/arm64/boot/

References:

IMX YOCTO PROJECT USERS GUIDE

IMX LINUX USERS GUIDE

IMX REFERENCE MANUAL