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+.. SPDX-License-Identifier: CC-BY-SA-2.0-UK
+
+Adding a New Machine
+********************
+
+Adding a new machine to the Yocto Project is a straightforward process.
+This section describes how to add machines that are similar to those
+that the Yocto Project already supports.
+
+.. note::
+
+   Although well within the capabilities of the Yocto Project, adding a
+   totally new architecture might require changes to ``gcc``/``glibc``
+   and to the site information, which is beyond the scope of this
+   manual.
+
+For a complete example that shows how to add a new machine, see the
+":ref:`bsp-guide/bsp:creating a new bsp layer using the \`\`bitbake-layers\`\` script`"
+section in the Yocto Project Board Support Package (BSP) Developer's
+Guide.
+
+Adding the Machine Configuration File
+=====================================
+
+To add a new machine, you need to add a new machine configuration file
+to the layer's ``conf/machine`` directory. This configuration file
+provides details about the device you are adding.
+
+The OpenEmbedded build system uses the root name of the machine
+configuration file to reference the new machine. For example, given a
+machine configuration file named ``crownbay.conf``, the build system
+recognizes the machine as "crownbay".
+
+The most important variables you must set in your machine configuration
+file or include from a lower-level configuration file are as follows:
+
+-  :term:`TARGET_ARCH` (e.g. "arm")
+
+-  ``PREFERRED_PROVIDER_virtual/kernel``
+
+-  :term:`MACHINE_FEATURES` (e.g. "screen wifi")
+
+You might also need these variables:
+
+-  :term:`SERIAL_CONSOLES` (e.g. "115200;ttyS0 115200;ttyS1")
+
+-  :term:`KERNEL_IMAGETYPE` (e.g. "zImage")
+
+-  :term:`IMAGE_FSTYPES` (e.g. "tar.gz jffs2")
+
+You can find full details on these variables in the reference section.
+You can leverage existing machine ``.conf`` files from
+``meta-yocto-bsp/conf/machine/``.
+
+Adding a Kernel for the Machine
+===============================
+
+The OpenEmbedded build system needs to be able to build a kernel for the
+machine. You need to either create a new kernel recipe for this machine,
+or extend an existing kernel recipe. You can find several kernel recipe
+examples in the Source Directory at ``meta/recipes-kernel/linux`` that
+you can use as references.
+
+If you are creating a new kernel recipe, normal recipe-writing rules
+apply for setting up a :term:`SRC_URI`. Thus, you need to specify any
+necessary patches and set :term:`S` to point at the source code. You need to
+create a :ref:`ref-tasks-configure` task that configures the unpacked kernel with
+a ``defconfig`` file. You can do this by using a ``make defconfig``
+command or, more commonly, by copying in a suitable ``defconfig`` file
+and then running ``make oldconfig``. By making use of ``inherit kernel``
+and potentially some of the ``linux-*.inc`` files, most other
+functionality is centralized and the defaults of the class normally work
+well.
+
+If you are extending an existing kernel recipe, it is usually a matter
+of adding a suitable ``defconfig`` file. The file needs to be added into
+a location similar to ``defconfig`` files used for other machines in a
+given kernel recipe. A possible way to do this is by listing the file in
+the :term:`SRC_URI` and adding the machine to the expression in
+:term:`COMPATIBLE_MACHINE`::
+
+   COMPATIBLE_MACHINE = '(qemux86|qemumips)'
+
+For more information on ``defconfig`` files, see the
+":ref:`kernel-dev/common:changing the configuration`"
+section in the Yocto Project Linux Kernel Development Manual.
+
+Adding a Formfactor Configuration File
+======================================
+
+A formfactor configuration file provides information about the target
+hardware for which the image is being built and information that the
+build system cannot obtain from other sources such as the kernel. Some
+examples of information contained in a formfactor configuration file
+include framebuffer orientation, whether or not the system has a
+keyboard, the positioning of the keyboard in relation to the screen, and
+the screen resolution.
+
+The build system uses reasonable defaults in most cases. However, if
+customization is necessary, you need to create a ``machconfig`` file in
+the ``meta/recipes-bsp/formfactor/files`` directory. This directory
+contains directories for specific machines such as ``qemuarm`` and
+``qemux86``. For information about the settings available and the
+defaults, see the ``meta/recipes-bsp/formfactor/files/config`` file
+found in the same area.
+
+Here is an example for "qemuarm" machine::
+
+   HAVE_TOUCHSCREEN=1
+   HAVE_KEYBOARD=1
+   DISPLAY_CAN_ROTATE=0
+   DISPLAY_ORIENTATION=0
+   #DISPLAY_WIDTH_PIXELS=640
+   #DISPLAY_HEIGHT_PIXELS=480
+   #DISPLAY_BPP=16
+   DISPLAY_DPI=150
+   DISPLAY_SUBPIXEL_ORDER=vrgb
+