RT-PREEMPT realtime kernel (Raspberry Pi)

For Raspberry Pi 2/3 using Raspbian:

Updated raspberrypi-bootloader is needed:

sudo apt-get update
sudo apt-get install -y raspberrypi-bootloader

Install kernel:

sudo -s
apt-get install linux-image-rpi2-rt
cd /boot
echo kernel=$(ls kernel_rt*.img) >> config.txt
echo device_tree=dtbs_rt/bcm2709-rpi-2-b.dtb >> config.txt

Then add the following entries to /boot/cmdline.txt:

dwc_otg.fiq_enable=0 dwc_otg.fiq_fsm_enable=0 dwc_otg.nak_holdoff=0