Digi Embedded Yocto builds a U-Boot bootloader, Linux kernel, and root file system image for your embedded Digi product. The following topic describes how to make changes to any of those components, which may be necessary in scenarios such as:

  • You have designed a custom carrier board for a Digi Embedded module and need to customize the U-Boot bootloader or Linux kernel

  • You need to customize the default Digi Embedded Yocto root file system images, or replace them with your own

  • You want to integrate your application into Digi Embedded Yocto so that it is built and included in the root file system

Digi Embedded Yocto layers

Digi Embedded Yocto will install a collection of package recipes, called meta-data, that are then used to build the different distribution elements. This meta-data is structured into several overlaying layers. Digi Embedded Yocto uses the following Yocto project layers:

  • poky, the Yocto project reference build system

  • meta-openembedded, a collection of package recipes

  • meta-st-stm32mp, provides support for STM-specific hardware platforms

  • meta-qt5, the layer supporting Qt5

  • meta-swupdate, providing support for software update mechanism

  • meta-webkit,, the layer supporting WebKit

Digi Embedded Yocto provides two extra layers to add support for Digi’s embedded platforms:

  • meta-digi-arm, which contains the BSP customization for Digi’s supported platforms

  • meta-digi-dey, which contains the Digi Embedded Yocto distribution and adds the following:

    • dey-image-qt, a graphical Qt image available for either:

      • Wayland graphical backend, or

      • EGLFS graphical backend

    • dey-image-webkit, a graphical WebKit image available for the Wayland graphical backend

    • dey-image-lvgl, a graphical Light and Versatile Graphics Library (LVGL) image available for the Wayland graphical backend

    • dey-image-crank, a graphical image available for the Wayland graphical backend with Crank Storyboard demos running