Linux Kernel

A common and unified Linux Kernel source tree is provided and used by the Linux microPlatform. The latest continuous release is available at github.com/foundriesio/linux.

The Linux Kernel recipe can be found in the Meta-LMP layer, under the meta-lmp/recipes-kernel/linux directory.

Linux microPlatform Kernel Configuration Fragments

Together with the unified Linux Kernel tree, the Linux microPlatform also provides an additional repository for the kernel configuration fragments. The latest continuous release for the kernel configuration fragments is available at github.com/foundriesio/lmp-kernel-cache.

You can find the list of supported BSP definitions and configuration fragments used under the lmp-kernel-cache/bsp directory.

The fragments repository works similarly to the upstream yocto-kernel-cache repository, so the same development workflow and documentation applies. See the Yocto Project Linux Kernel Development Manual for more information on how to work and manage the kernel metadata and configuration fragments.

Linux microPlatform with Linux upstream

The recipe meta-lmp/recipes-kernel/linux/linux-lmp-dev.bb can be used to build the Linux microPlatform with the upstream kernel tree instead of the LMP unified tree. linux-lmp-dev also uses the Linux microPlatform Kernel Configuration Fragments repository for a compatible configuration.

Building Linux microPlatform with linux-lmp-dev

Set the PREFERRED_PROVIDER_virtual/kernel to linux-lmp-dev in conf/auto.conf after setting up your Linux microPlatform development environment (source setup-environment):

$ echo 'PREFERRED_PROVIDER_virtual/kernel = "linux-lmp-dev"' >> conf/auto.conf

Now just build any of the supported Linux microPlatform images.

Specifying Linux git tree, branch and commit revision

The following variables can be also set in conf/auto.conf in order to build linux-lmp-dev using a specific linux tree, branch or commit revision:

KERNEL_REPO = "git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git" # Kernel git repository
KERNEL_BRANCH = "master" # Git kernel branch (default: master)
KERNEL_COMMIT = "94710cac0e" # Kernel commit revision (default: HEAD)
KERNEL_META_REPO = "git://github.com/foundriesio/lmp-kernel-cache.git" # Kernel configuration fragments repository
KERNEL_META_BRANCH = "master" # Git kernel meta branch (default: master)
KERNEL_META_COMMIT = "1c67180cfe" # Kernel meta commit revision (default: HEAD)
LINUX_VERSION = "4.19-rc" # Linux kernel base version (base package version)