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 # Copyright (c) 2022, Arm Limited.
 #
 # SPDX-License-Identifier: MIT

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Yocto Layers
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The Armv8-R AArch64 software stack is provided through the `v8r64`_
repository. The v8r64 repository provides a Yocto Project compatible layer --
``meta-armv8r64-extras`` -- with target platform (`fvp-baser-aemv8r64`_)
extensions for Armv8-R AArch64. Currently this layer extends the
``fvp-baser-aemv8r64`` machine definition from the meta-arm-bsp layer in the
`meta-arm`_ repository.

.. _v8r64: https://gitlab.arm.com/automotive-and-industrial/v8r64
.. _fvp-baser-aemv8r64: https://git.yoctoproject.org/meta-arm/tree/meta-arm-bsp/documentation/fvp-baser-aemv8r64.md
.. _meta-arm: https://git.yoctoproject.org/meta-arm/tree/?h=kirkstone

The following diagram illustrates the layers which are integrated in the
software stack, which are further expanded below.

.. image:: /images/armv8r64-yocto-layers.png
   :alt: Arm v8r64 Yocto layers

* poky layers (meta, meta-poky)

  * URL: https://git.yoctoproject.org/poky/?h=kirkstone
  * Provides the base configuration, including the 'poky' distro.

* meta-arm layers (meta-arm-bsp, meta-arm, meta-arm-toolchain)

  * URL: https://git.yoctoproject.org/meta-arm/?h=kirkstone
  * meta-arm-bsp contains the board support to boot baremetal Linux for the
    ``fvp-baser-aemv8r64`` machine. It includes

    * The base device tree
    * Machine-specific boot-wrapper-aarch64 patches
    * Machine-specific U-Boot patches

  * meta-arm contains:

    * A recipe for the FVP_Base_AEMv8R model itself
    * The base recipe for boot-wrapper-aarch64

  * meta-arm-toolchain is not used, but is a dependency of meta-arm.

* meta-virtualization

  * URL: https://git.yoctoproject.org/meta-virtualization/?h=kirkstone
  * Included for the virtualization stack only.

* meta-openembedded layers (meta-oe, meta-python, meta-filesystems,
  meta-networking)

  * URL: http://git.openembedded.org/meta-openembedded?h=kirkstone
  * These are dependencies of meta-virtualization, so are included for the
    virtualization stack only.