\subsection{Add own kernel}
\begin{frame}
\frametitle{Workflow}
\begin{itemize}
\item Configure and build kernel without yocto
\item Extract Kernel configuration and source/patches
\item Integrate source, config and patches into yocto
\end{itemize}
\end{frame}

\begin{frame}[fragile]
\frametitle{Kernel configuration}
\begin{lstlisting}
$ cd ~
$ git clone linux.git
$ cd linux
$ git checkout -b linux-4.19.1 v4.19.1
$ git archive --format=tar.gz \
              --prefix=linux-4.19.1/ \
              -o ../linux-4.19.1.tar.gz HEAD
$ ARCH=arm make vexpress_defconfig
\end{lstlisting}
\end{frame}

\begin{frame}[fragile]
\frametitle{Add a kernel recipe}
\begin{lstlisting}
$ cd ~/poky/meta-schulung
$ mkdir -p recipes-bsp/linux-vanilla/files/vexpress
$ mv ~/linux-4.19.1.tar.gz recipes-bsp/linux-vanilla/files
$ cp ~/linux/.config recipes-bsp/linux-vanilla/files/vexpress/defconfig
$ pluma recipes-bsp/linux-vanilla/linux-vanilla_4.19.1.bb
\end{lstlisting}
\begin{verbatim}
SECTION = "kernel"
DESCRIPTION = "Linux vanilla kernel"
LICENSE = "GPLv2"
LIC_FILES_CHKSUM = "file://COPYING;md5=bbea815ee2795b2f4230826c0c6b8814"
inherit kernel
COMPATIBLE_MACHINE_vexpress = "vexpress"
KERNEL_DEVICETREE_vexpress = "vexpress-v2p-ca9.dtb"
SRC_URI = "file://linux-${PV}.tar.gz file://defconfig"
S = "${WORKDIR}/linux-${PV}"
\end{verbatim}
\end{frame}


\begin{frame}[fragile]
\frametitle{Use own kernel recipe}
\begin{lstlisting}
$ cd ~/poky/meta-schulung
$ pluma conf/machine/vexpress.conf
\end{lstlisting}
\begin{verbatim}
DEFAULTTUNE ?= "armv7athf-neon"
require conf/machine/include/tune-cortexa8.inc
SERIAL_CONSOLE = "115200 ttyAMA0"
PREFERRED_PROVIDER_virtual/kernel = "linux-vanilla"
\end{verbatim}
\begin{lstlisting}
$ cd ~/poky/build-schulung
$ bitbake core-image-schulung
\end{lstlisting}
\end{frame}