OK3588 5.10.209 Buildroot Filesystem Building & System Tool Adding

Document classification: □ Top secret □ Secret □ Internal information ■ Open

Revision History

Date

Version

Revision History

30/04/2025

V1.0

Initial Version

Filesystem Building & System Tool Adding

The manual mainly describes the customized modification operations performed on the Buildroot for Linux 5.10.209.

Download and Extract SDK Source Code

forlinx@ubuntu20:~/3-3588-SDK_Kernel_5.10.209/1-Linux5.10.209+Qt5.15.10+Forlinx_Desktop22.04/OK3588-linux-source$ ls
app             build_secret_uboot.sh  debian  external  output     rkbin       rtos    ubuntu
build_close.sh  build.sh               device  kernel    prebuilts  rkflash.sh  tools   uefi
buildroot       common                 docs    Makefile  README.md  rockdev     u-boot  yocto

Allow Compiling Buildroot First

Before compiling, ensure that Buildroot can be compiled by deleting or removing the rootfs.ext4 file in the relevant directory (you can move it to another directory or rename it).

forlinx@ubuntu20:~/3-3588-SDK_Kernel_5.10.209/1-Linux5.10.209+Qt5.15.10+Forlinx_Desktop22.04/OK3588-linux-source/prebuilts/forlinx/buildroot$ ls
rootfs.ext4

Compile Default Configuration Items

To ensure compatibility with the previous default Buildroot configuration (forlinx_ok3588_defconfig), recompile by executing ./build.sh or ./build.sh buildroot.

During the build process, the server will fetch the source code packages for software projects based on the forlinx_ok3588_defconfig configuration and place them in the /buildroot/package directory.

forlinx@ubuntu20:~/3-3588-SDK_Kernel_5.10.209/1-Linux5.10.209+Qt5.15.10+Forlinx_Desktop22.04/OK3588-linux-source/buildroot/package$

After compilation, numerous files will be added and generated. The following files and directories will be created under buildroot/output/forlinx_ok3588/:

buildroot/output/forlinx_ok3588/ generate files

Table of Contents

Role

Description

build

Stores intermediate and temporary files generated during compilation.

Deleting this directory will result in a long recompilation

host

Contains tools and binaries compiled for the build system host

(i.e., the cross-compiler)

images

Stores the final firmware image files

rootfs.ext4 is the Buildroot system image, which can be directly replaced.

scripts

Contains various script files used by Buildroot.

Used for automated builds, configuring environments, or handling specific tasks.

staging

Contains header files, library files, and other development-related files for the target system.

Required during cross-compilation

target

Contains the complete contents of the root file system (rootfs) for the target device.

Includes only runtime-required files, excluding development-related header files or libraries.

After compilation, it will be directly packaged into update.img.

Note: Many issues may arise during this process, such as package acquisition failures due to network timeouts, insufficient thread counts during compilation, insufficient memory, or insufficient swap partitions. Generally, non-software project source code issues should be considered from these aspects. Remember not to use sudo with root privileges.

Adding System Tools or Required Library Files to Buildroot

Taking OpenCV4 as an example:

① Enter the Buildroot directory and compile the forlinx_ok3588_defconfig.

make forlinx_ok3588_defconfig

② Open the menuconfig graphical interface and select the projects you want to compile.

make menuconfig ARCH=arm64

![Image](./images/OK3588_Linux 5_10_209_Buildroot_Filesystem_Building_System_Tool_Adding/20250430141844.png)

Selection Option

Role

Target options

Configure the architecture and hardware parameters of the target device

Build options

Configure Buildroot’s Build operations

Toolchain

Configuring the cross-compilation toolchain

System configuration

Configure basic settings for the target system

Kernel

Configure the Linux kernel

Target packages

Select the packages installed on the target system

Filesystem images

Configure the type of file system image that is generated

Bootloaders

Configure the boot loader (e.g. U-Boot, GRUB)

Host utilities

Configure the tools that run on the host

Legacy config options

Dealing with obsolete or obsolete configuration options

For example, if you need opencv4 now, you can directly search in the visual list, check the configuration items you need, and then save them to generate a new.config.

③ Compilation

Separate Tool Package Compilation:

make opencv4

Full Compilation:

	Direct execute make

make

④ After completing the full compilation: Buildroot will automatically add the executable files and dependency libraries for OpenCV4 to the target file system. These files will be located in buildroot/output/forlinx_ok3588/image/rootfs.ext4.

Buildroot will also copy the dependency libraries required for compiling OpenCV4 to the toolchain. These libraries will be stored in the host directory under buildroot/output/forlinx_ok3588, as mentioned earlier. If necessary, the compiler can be packaged and used.

Usage: directly set the environment-setup environment variable under the host directory to deploy the cross-compilation environment

source environment-setup

⑤ Save the current configuration to defconfig

	It is recommended to back up and keep the original forlinx_ok3588_defconfig

make savedefconfig

Replacement and Transplantation

Generally, the cross-compilation tool and the generated file system image are used, respectively

buildroot/output/forlinx_ok3588/host

buildroot/output/forlinx_ok3588/image/rootfs.ext4