Architecture¶

meta-tolomeo separates concerns across four Yocto layers so that application content, distribution policy, hardware support, and virtualization can evolve independently. A BSP integrator can replace or customize any single layer without affecting the others.

Target Platforms¶

Hardware support for production deployment is provided by meta-tolomeo-nxp, targeting the NXP i.MX8M Plus. Three QEMU machines are provided for development and testing.

Layer Structure¶

meta-tolomeo-app¶

Application and service definitions: ToloMEO Manager (web-based management interface), system monitoring (Glances), OTA update services, and security tooling (Lynis, hardening checker). Separated from the distro layer so image composition can change without touching security policy.

meta-tolomeo-distro¶

Distribution configurations, security hardening flags, and custom bbclasses. Provides two distributions: tolomeo-prod (security-hardened, audit, integrity, secure-boot enabled) and tolomeo-devel (debug tools, ptest enabled). Centralizes cross-cutting concerns — SBOM generation, update infrastructure, integrity checking — decoupled from both hardware and application layers.

meta-tolomeo-nxp¶

Hardware BSP layer for NXP i.MX8M Plus: machine configurations, hardware drivers, board support, and NXP CST integration for secure boot and image signing. Hardware-specific details are isolated here so they do not propagate to the distro or application layers.

meta-tolomeo-qemu¶

QEMU machine definitions for x86-64, AArch64, and ARM targets. Provides VirtIO device support, shared folder configuration, and overlay disk support. These machines provide a functionally equivalent virtual target so the full distro and application stack can be developed and tested without hardware.

Build Configurations¶

Kas configuration files are currently provided for the QEMU x86-64 target. All follow the naming convention:

<machine>_<distro>_<image>.yml