Build Your Image¶

NetModule provides its own meta layer for customized image generation.

Project Setup¶

Netmodule Meta Layer¶

Meta Layer	Description	Repository
meta-netmodule-distro	Distribution specfic contents Distribution configurations NetModule image recipes Firmware update tool Disk expansion tool General applications recipes Example local.conf file	meta-netmodule-distro
meta-netmodule-bsp	Distribution specific contents Machine confguration files U-Boot recipes Linux kernel recipe Applications recipes for interface support General low level applications recipes	meta-netmodule-bsp
meta-netmodule-wlan	Wlan module firmware Wireless regulatory databases WPA supplicant Wireless tools	meta-netmodule-wlan

Additional Layers and Bitbake¶

Following additional resources are required:

Setup workspace¶

Start new build project with cloning all required git repositories:

Clone the nm-oem-linux repository
Move into the cloned repository and run git submodule init then git submodule update
Your workspace should now look similar as in the snippet below:

.
├── bitbake
├── build
├── env
├── meta-netmodule-bsp
├── meta-netmodule-distro
├── meta-netmodule-wlan
├── meta-openembedded
├── meta-updater
├── openembedded-core
└── README.md

Configure project¶

Start to source environment: . ./env/distro/ostree-image select your hardware in the prompt. You will be moved to the build directory.

Build NetModule reference images¶

NetModule provides several reference images depends on use case:

Image	Description
netmodule-linux-image	Standard reference image. Contains required applications, drivers and tools to use interfaces, network connectivities and sensors.
netmodule-linux-image-dev	Based on `netmodule-linux-image` and extended with helpful development tools for low level access (e.g. direct access on i2c bus) and generic debug tools like strace and gdb.
netmodule-linux-image-minimal	Minimal ramdisk based image for simple bring up or can be used for emmc operations like device flashing or data recovery.

Images recipes location¶

Images recipes are located in layer meta-netmodule-distro:

meta-netmodule-distro/recipes-core/images/
├── includes
│   ├── firmware.inc
│   └── image-preprocessing.inc
├── initramfs-ostree-image.bbappend
├── netmodule-linux-image.bb
├── netmodule-linux-image-dev.bb
├── netmodule-linux-image-mdev.bb
├── netmodule-linux-image-minimal.bb
├── netmodule-linux-image-oem.bb
└── nmcontainer-python3.bb

Building with shared state¶

It is highly recommended to use the yocto shared state from NetModule to speed up build time. Also some closed source tools like “lpa” will only be available through sstate. The sstate will provide already built packages directly from our servers as long as the recipes configurations are the same.

To build using our sstate, make sure that all the layers are matching the submodule hashes from our releases and make sure that the following line is present in your local.conf:

SSTATE_MIRRORS = "file://.* https://nmrepo.netmodule.com/chbe/oem-linux-sstate/PATH"

Images build instructions¶

Start image build after sourcing environment with:

bitbake netmodule-linux-image

Images deploy location¶

Built images are located in deploy directory.::: <project root>/build/tmp/deploy/images/<hw type e.g. am335x-nmhw21>/