Xenomai 3.0.7 on Raspberry Pi 3

This short guide explains how to put Xenomai 3 Cobalt on the Raspberry Pi 3.

System setup

• Download Raspian from https://www.raspberrypi.org/downloads/raspbian/

• Use lsblk to discover the flash device. Then, flash the image through:

   dd bs=4M if=2018-04-18-raspbian-stretch.img of=/dev/sdX conv=fsync
  

• Credentials: pi/raspberry

• Run rpi-update

• Run raspi-config for enabling SSH and serial console (in "Interfacing Options")

Kernel build

To configure the kernel (optional) type:

    export CROSS_COMPILE=arm-linux-gnueabihf- (or your specific toolchain)

    make configure

To cross-compile the kernel follow the next steps:

    export CROSS_COMPILE=arm-linux-gnueabihf- (or your specific toolchain)

    make kernel

The cross-compiler binaries must be in the current PATH.

Note that the initial default kernel configuration is available in the kernel/kernel-config file.

Kernel installation

• Copy the following files to the target:

  • kernel/linux-4.14.36/build/linux/arch/arm/boot/dts/bcm2837-rpi-3-b.dtb -> /boot/
  • kernel/linux-4.14.36/build/linux/arch/arm/boot/zImage -> /boot/kernel-xenomai.img
  • kernel/linux-4.14.36/build/linux/MODULES/ -> /lib/modules

• Append to /boot/config.txt:

    device_tree=bcm2837-rpi-3-b.dtb
    kernel=kernel-xenomai.img
  

• Append to /boot/cmdline.txt:

    cma=256M@512M
  

Drivers build

To cross-compile the exemplary drivers follow the next steps:

    export CROSS_COMPILE=arm-linux-gnueabihf- (or your specific toolchain)

    make drivers

User-space tools

To natively compile the Xenomai user-space tools on the Rpi3 target, type:

   make tools

   sudo make tools_install

To run the default benchmark, type

   sudo /usr/xenomai/bin/xeno-test

References

• Xenomai installation guide: https://xenomai.org/installing-xenomai-3-x/
• I-pipe download: https://xenomai.org/downloads/ipipe/
• Xenomai download: https://xenomai.org/downloads/xenomai/stable/latest/
• I-pipe tracer: https://xenomai.org/2014/06/using-the-i-pipe-tracer/
• Xenomai driver programming API: https://xenomai.org/documentation/xenomai-3/html/xeno3prm/group__rtdm__driver__interface.html