🚀 Real-Time Kernel Deployment for RaspberryPi 🥧

This guide will walk you through the process of building and deploying a real-time kernel for the ComfilePi.

🛠 Prerequisites

• Raspberry Pi (preferably Raspberry Pi 4 or newer)
• MicroSD card with Raspbian OS installed
• Internet connection
• External keyboard, mouse, and monitor (for ease of setup)

📥 Fetching and Building the Kernel

1. Update your system:

   sudo apt update && sudo apt upgrade -y

2. Install necessary packages:

   sudo apt install git bc bison flex libssl-dev make libc6-dev libncurses5-dev crossbuild-essential-$ARCH

3. Clone the Raspberry Pi kernel repository:

   git clone --depth=1 --branch $KERNEL_BRANCH https://github.com/raspberrypi/linux.git

4. Download and apply the RT patch:

   wget http://cdn.kernel.org/pub/linux/kernel/projects/rt/$KERNEL_VERSION/older/patch-$RT_PATCH_VERSION.patch.gz
   gunzip patch-$RT_PATCH_VERSION.patch.gz
   cd linux
   patch -p1 < ../patch-$RT_PATCH_VERSION.patch

5. Configure and compile the kernel: Follow the steps provided in the build script.

🚚 Deploying to the RaspberryPi

1. Package up the result into a single file:

   tar czf rtkernel.tgz -C rtkernel/result/ .

2. Transfer the file to the ComfilePi:

   scp rtkernel.tgz [username]]@[ip_address]:

3. Install the kernel assets on the ComfilePi:

   sudo tar xzf rtkernel.tgz --directory / --keep-directory-symlink --no-same-owner

4. Verify the kernel version:

   uname -a

   The output should resemble:

   Linux raspberrypi 6.1.21-rt8-v8+ #1 SMP PREEMPT_RT Fri May 12 10:19:19 KST 2023 aarch64 GNU/Linux
   

🎉 Conclusion

With the RT patch, the Raspberry Pi should be able to respond to events within the 1ms timeframe, even under heavy load. This ensures predictability and timely response to events, making it ideal for real-time applications.