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kernel / pub / scm / utils / dtc / dtc / 589d8c7653c75d789c6e47d69a4f5bb089aecd5a
commit589d8c7653c75d789c6e47d69a4f5bb089aecd5a[log] [tgz]
authorUwe Kleine-König <u.kleine-koenig@pengutronix.de>Tue May 23 10:09:41 2023 +0200
committerDavid Gibson <david@gibson.dropbear.id.au>Fri May 26 21:11:32 2023 +1000
tree04c6e5db5c79b240075920cde0cf927b72986cf8
parente8364666d5acc985c434fb574e92c5206d9a8d6b [diff]
dtc: Add an option to generate __local_fixups__ and __fixups__

This records detailed usage of labels in a dtb. This is needed in
overlays (and enabled implicitly for these). For ordinary device trees
it can be used to restore labels when compiling back to dts format.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Message-Id: <20230523080941.419330-1-u.kleine-koenig@pengutronix.de>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2 files changed
tree: 04c6e5db5c79b240075920cde0cf927b72986cf8
  1. .github/
  2. Documentation/
  3. libfdt/
  4. pylibfdt/
  5. scripts/
  6. tests/
  7. .editorconfig
  8. .gitignore
  9. BSD-2-Clause
  10. checks.c
  11. CONTRIBUTING.md
  12. convert-dtsv0-lexer.l
  13. data.c
  14. dtc-lexer.l
  15. dtc-parser.y
  16. dtc.c
  17. dtc.h
  18. dtdiff
  19. fdtdump.c
  20. fdtget.c
  21. fdtoverlay.c
  22. fdtput.c
  23. flattree.c
  24. fstree.c
  25. GPL
  26. livetree.c
  27. Makefile
  28. Makefile.convert-dtsv0
  29. Makefile.dtc
  30. Makefile.utils
  31. MANIFEST.in
  32. meson.build
  33. meson_options.txt
  34. README.license
  35. README.md
  36. setup.py
  37. srcpos.c
  38. srcpos.h
  39. TODO
  40. treesource.c
  41. util.c
  42. util.h
  43. version_gen.h.in
  44. yamltree.c
README.md

Device Tree Compiler and libfdt

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:

Python library

A Python library wrapping libfdt 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.

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