Yocto Layers

The meta-cassini repository provides three layers compatible with the Yocto Project, in the following sub-directories:

  • meta-cassini-bsp

    A Yocto layer which holds board-specific recipes or append files that either:

    • will not be upstreamed (Cassini specific modifications)

    • have not been upstreamed yet

    • For the N1SDP hardware target platform, this layer currently extends the n1sdp machine definition from the meta-arm-bsp layer with additional Trusted Services (crypto, storage, internal trusted storage, attestation , block storage)

  • meta-cassini-distro

    A Yocto distribution layer providing top-level and general policies for the Cassini distribution images.

  • meta-cassini-tests

    A Yocto software layer with recipes that include run-time tests to validate Cassini functionalities.

Layer Dependency Overview

The following diagram illustrates the layers which are integrated by the Cassini project, which are further expanded on below. The layer revisions are related to the Cassini v1.0.0 release.


Cassini distribution depends on the following layer dependency sources:

URL: https://git.yoctoproject.org/git/poky
layers: meta, meta-poky
branch: mickledore
revision: 0a98281d37b0bd8dc1548c390216cb3978e36e0e

URL: https://git.openembedded.org/meta-openembedded
layers: meta-filesystems, meta-networking, meta-oe, meta-python
branch: mickledore
revision: 03fd1d368ac19793b3e4c35159ba2ce802247e4d

URL: https://git.yoctoproject.org/git/meta-virtualization
layer: meta-virtualization
branch: mickledore
revision: b2bac21615b16dfd281646ee8b0f1e384981633e

URL: https://git.yoctoproject.org/git/meta-security
layers: meta-parsec
branch: mickledore
revision: d7db0a3bd1a8639df7570483f003ce00cbe274a2

An additional layer dependency source is conditionally required, depending on the specific Cassini distribution image being built. This layer dependency source is the meta-arm repository, which provides three Yocto layers:

URL: https://git.yoctoproject.org/git/meta-arm
layers: meta-arm, meta-arm-bsp, meta-arm-toolchain
branch: mickledore
revision: 10c355b9c7c1376301e9fceb5d40a5a7247ced17

The layers required from meta-arm depend on the Cassini distribution image:

  • Cassini SDK distribution images require meta-arm and meta-arm-toolchain, as the gator-daemon package is installed on the rootfs.

  • A Cassini distribution image built for the N1SDP hardware target platform requires meta-arm, meta-arm-bsp, and meta-arm-toolchain.

These layers are described as follows: