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Linux® OS for MPUs

The Linux® Operating System (OS) has become pervasive in all aspects of the digital world, largely due to its long-standing history as one of the most reliable, secure and worry-free operating systems available. The Linux OS and Microchip’s microprocessors (MPUs) have gone hand in hand since 2002 when our first MPU, the AT91RM9200, was introduced.

By supporting mainline Linux, our customers receive the full support of the open source community to create high-quality solutions. Microchip has been mainlining its kernel, bootloader and drivers since 2004, and mainlining has become a centerpiece of our Linux strategy because of the value it brings to users. Microchip uses its linux4sam.org website to provide access to new developments which are reviewed by our Linux maintainers and fully tested on our hardware platforms. Using Long-Term Support (LTS) Linux kernels provides access to kernel maintenance for two to six years. Linux provided by Microchip still uses the AT91RM9200 peripheral drivers, thus facilitating software portability between each kernel release, eliminating the need to update drivers.

To get started with Linux on our microprocessors and explore the potential of the combined hardware and software platform, we recommend the ATSAM5D27-SOM1-EK1 evaluation kit. Watch this video to learn more:

Linux Logo
  • Device tree support
  • Yocto and Buildroot build environments
  • Solid and proven peripheral drivers
  • Large developer community
  • Security updates
  • Maintaining multiple stable kernels
Yocto Project
Yocto Logo

The Yocto Project® is an open source collaboration project that provides templates, tools, methods and documentation to help developers create Linux-based systems for embedded products. The free tools make getting started easy, are powerful to work with (including emulation environments, debuggers, an Application Toolkit Generator, etc.) and allow projects to evolve across all stages of development from prototype to production.

Buildroot Logo

Buildroot is a simple, efficient and easy-to-use tool to generate embedded Linux systems through cross-compilation. Buildroot is an open source project with daily contributions from developers.


AT91Bootstrap and U-boot

AT91Bootstrap is the second level bootloader for Microchip’s microprocessors. It provides a device support package to manage the hardware initialization, such as clock speed configuration, PIO settings and DRAM initialization.

U-Boot (Universal-Bootloader) is a third level bootloader. It configures the main interfaces like USB and Ethernet and launches the Linux operating system. U-Boot facilitates the initial board bring-up and software development phase.


OpenWrt is an open source project for embedded operating systems based on Linux, primarily used on embedded devices to route network traffic. All components have been optimized to be small enough to fit into the limited storage and memory available in existing in-home routers.