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+The source tree contains the Device Tree Compiler (dtc) toolchain for
+working with device tree source and binary files and also libfdt, a
+utility library for reading and manipulating the binary format.
+
+DTC and LIBFDT are maintained by:
+
+David Gibson <david@gibson.dropbear.id.au>
+Jon Loeliger <loeliger@gmail.com>
+
+
+Python library
+--------------
+
+A Python library is also available. To build this you will need to install
+swig and Python development files. On Debian distributions:
+
+   sudo apt-get install swig python3-dev
+
+The library provides an Fdt class which you can use like this:
+
+$ PYTHONPATH=../pylibfdt python3
+>>> import libfdt
+>>> fdt = libfdt.Fdt(open('test_tree1.dtb', mode='rb').read())
+>>> node = fdt.path_offset('/subnode@1')
+>>> print(node)
+124
+>>> prop_offset = fdt.first_property_offset(node)
+>>> prop = fdt.get_property_by_offset(prop_offset)
+>>> print('%s=%s' % (prop.name, prop.as_str()))
+compatible=subnode1
+>>> node2 = fdt.path_offset('/')
+>>> print(fdt.getprop(node2, 'compatible').as_str())
+test_tree1
+
+You will find tests in tests/pylibfdt_tests.py showing how to use each
+method. Help is available using the Python help command, e.g.:
+
+    $ cd pylibfdt
+    $ python3 -c "import libfdt; help(libfdt)"
+
+If you add new features, please check code coverage:
+
+    $ sudo apt-get install python3-coverage
+    $ cd tests
+    # It's just 'coverage' on most other distributions
+    $ python3-coverage run pylibfdt_tests.py
+    $ python3-coverage html
+    # Open 'htmlcov/index.html' in your browser
+
+
+The library can be installed with pip from a local source tree:
+
+    pip install . [--user|--prefix=/path/to/install_dir]
+
+Or directly from a remote git repo:
+
+    pip install git+git://git.kernel.org/pub/scm/utils/dtc/dtc.git@main
+
+The install depends on libfdt shared library being installed on the host system
+first. Generally, using --user or --prefix is not necessary and pip will use the
+default location for the Python installation which varies if the user is root or
+not.
+
+You can also install everything via make if you like, but pip is recommended.
+
+To install both libfdt and pylibfdt you can use:
+
+    make install [PREFIX=/path/to/install_dir]
+
+To disable building the python library, even if swig and Python are available,
+use:
+
+    make NO_PYTHON=1
+
+
+More work remains to support all of libfdt, including access to numeric
+values.
+
+
+Adding a new function to libfdt.h
+---------------------------------
+
+The shared library uses libfdt/version.lds to list the exported functions, so
+add your new function there. Check that your function works with pylibfdt. If
+it cannot be supported, put the declaration in libfdt.h behind #ifndef SWIG so
+that swig ignores it.
+
+
+Tests
+-----
+
+Test files are kept in the tests/ directory. Use 'make check' to build and run
+all tests.
+
+If you want to adjust a test file, be aware that tree_tree1.dts is compiled
+and checked against a binary tree from assembler macros in trees.S. So
+if you change that file you must change tree.S also.
+
+
+Mailing list
+------------
+The following list is for discussion about dtc and libfdt implementation
+mailto:devicetree-compiler@vger.kernel.org
+
+Core device tree bindings are discussed on the devicetree-spec list:
+mailto:devicetree-spec@vger.kernel.org