Compiling Buildroot from scratch

Buildroot is a simple, efficient and easy-to-use tool to generate embedded Linux systems through cross-compilation. This article illustrates how to generate a ready-to-use microSD image from scratch using the Buildroot scripts and utilities to download the sources of any code, compile them and generate a fully working bootable microSD.

The article steps has been tested using a Linux PC with Linux Ubuntu 22.04.2 LTS.

It is advisable to have an USB to 3V TTL serial cable or a DPI interface.

Building procedure

Install on your Linux PC the requested packages listed here:

Open a command line terminal and download Buildroot from the official web site:

$ wget
$ tar -xvf buildroot-2024.02.1.tar.gz
$ cd buildroot-2024.02.1

Create a git repository:

$ git init
$ git add .
$ git commit -m "vanilla"
$ git branch acme
$ git checkout acme

Download the patch for the Acme board you have (just one):

$ wget -O acme.patch
$ wget -O acme.patch
$ wget -O acme.patch

Apply the patch:

$ patch -p1 < acme.patch

set the right configuratione (just one):

$ make arietta_defconfig
$ make foxd27_defconfig

Launch the compilation:

$ make

This operation will take about 1 hour to download and compile any sources.

If all went well you will obtain this file in output/images directory:


Install new packages

To install new packages from the menuconfig menu type:

$ make menuconfig

Then repeat the procedure to generate the new microSD image from Make command.

Regenerate the target directory

$ rm -rf output/target
$ find output/ -name ".stamp_target_installed" -delete
$ rm -f output/build/host-gcc-final-*/.stamp_host_installed

Change the Linux Kernel configuration

$ make linux-menuconfig
$ make linux-rebuild
$ make

Save the kernel config

$ make linux-savedeconfig


File used:

Buildroot ready-to-use application image for FOX D27

Download ready-to-use microSD images for your boards

  • Arietta
    Buildroot 2024.02.1, Kernel 6.1, At91Boostrap 3.10.4, lighttpd, Python3, RNDIS drivers
  • Fox Board D27
    Buildroot 2024.02.1, Kernel 6.1, At91Boostrap 3.10.4, lighttpd, Python3

Create a bootable microSD

Download and install the free tool Balena Etcher available for any platform to write the microSD using the filename.img generated by scratch od downloaded:

Insert the microSD generated in your board and use the debug port to check the boot messages and get the access to the Linux prompt.

Partition resizing

Type this command to check how is partitioned the microSD

$ parted /dev/mmcblk0 --script print

Model: SD SS08G (sd/mmc)
Disk /dev/mmcblk0: 7948MB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags: 

Number  Start   End     Size    Type     File system  Flags
 1      512B    16.8MB  16.8MB  primary  fat16        boot, lba
 2      16.8MB  101MB   83.9MB  primary  ext4

To resize the root partition to fill the entire microSD type:

$ parted /dev/mmcblk0 --script resizepart 2 100%
$ resize2fs /dev/mmcblk0p2

Check it again:

$ parted /dev/mmcblk0 --script print

Model: SD SS08G (sd/mmc)
Disk /dev/mmcblk0: 7948MB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags: 

Products related

Arietta G25

Features Index Buy

Linux System On Module
  • CPU Microchip AT91SAMG25
  • ARM9 @ 400 MHz
  • Armel architecture
  • DDR2 RAM 128/256 MB
  • Size: 53x25 mm
  • Plug-in module
  • 40 pins 2.54 mm pitch
  • Boot from uSD
  • Linux Kernel 5.15 LTS
  • Debian, Buildroot and Yocto Linux
  • Fully open source drivers

Features Index Buy

Single Board Computer based on RoadRunner Linux SOM (Included)
  • Low power consumption
  • Two USB Host 2.0 ports (one configurable as USB client on the USB-C connector)
  • One 10/100 Mbit/s Lan port
  • 2 Acme Sensor ports
  • Huge set of GPIOS, SPI, I2C and serial lines