Custom Linux kernel for NextThing Co. C.H.I.P.

Quick and dirty kernel build for the Next Thing Co's C.H.I.P. $9 single board computer.

This builds the kernel on the C.H.I.P. itself.

Alternatively grab this gist and put it in a directory of it's own. It will pull down the sources and build everything you need. To cross compile on a Debian or Ubuntu system apt-get install crossbuild-essentials-armhf first.

Install dev tools

sudo apt-get update
sudo apt-get upgrade
sudo apt-get install build-essential zlib1g-dev libncurses5-dev loop
sudo apt-get clean

Kernel Build

# Create a directory to hold the source files
cd ~
mkdir src

# Clone the NTC Kernel source
cd src
git clone --single-branch --branch debian/4.4.11-ntc-1 --depth 1

# Configure the kernel
cp /boot/config-4.4.11-ntc CHIP-linux/.config
cd CHIP-linux
make oldconfig

# Add any extra modules you might want and kernel version here
make menuconf

# Build the kernel (this will take a loooong time)

# Install the modules
sudo make install modules_install

RTL8723BS Wireless Build

# Clone the source code
cd ~/src
git clone --single-branch --branch debian

# Apply patches
cd RTL8723BS/
for f in debian/patches/0*; do echo "Applying ${f}"; patch -p 1 < $f; done

# Build the source
make CONFIG_PLATFORM_ARM_SUNxI=y -C /home/chip/src/CHIP-linux/ M=$PWD CONFIG_RTL8723BS=m

# Install the module
sudo make -C /home/chip/src/CHIP-linux/ M=$PWD modules_install

Install kernel

Name the kernel file with the version that you built. If you added an extra version information in the kernel config then include this as well.

Copy the new kernel to /boot

export KV=4.4.11-td1+
cd ~/src/CHIP-linux
sudo cp arch/arm/boot/zImage /boot/vmlinuz-$KV
sudo cp .config /boot/config-$KV
sudo cp /boot/$KV

Copy the device tree files to /boot

export KV=4.4.11-td1+
sudo mkdir /boot/dtbs/$KV
sudo cp arch/arm/boot/dts/sun5i-r8-chip.dtb /boot/dtbs/$KV/

This makes it easier to change your kernel, all you need to do is change the symlink that zImage points to.

cd /boot

# Backup existing kernel and other files
for F in config zImage dtb; do sudo mv $F $F-$(uname -r); done
sudo mkdir dtbs/$(uname -r)
sudo mv sun5i-r8-chip.dtb dtbs/$(uname -r)/

# Create links to new kernel and other files
export KV=4.4.11-td1+
for F in config zImage; do sudo ln -sf $F-$KV $F; done
sudo ln -sf sun5i-r8-chip.dtb dtbs/$KV/sun5i-r8-chip.dtb
chip@chip-one:/boot$ ls -la config zImage sun5i-r8-chip.dtb
lrwxrwxrwx 1 root root 18 Jul  5 21:33 config -> config-4.4.11-td1+
lrwxrwxrwx 1 root root 15 Jul  5 21:32 sun5i-r8-chip.dtb -> dtb-4.4.11-td1+
lrwxrwxrwx 1 root root 22 Jul  5 21:33 ->
lrwxrwxrwx 1 root root 19 Jul  5 21:31 zImage -> vmlinuz-4.4.11-td1+


systemctl reboot

Your C.H.I.P. should now reboot and be running your new kernel