| commit | c8d1d863ab72b74efe7bda4c80579968716708a6 | [log] [tgz] |
|---|---|---|
| author | Pierre-Clément Tosi <ptosi@google.com> | Wed Oct 11 16:37:55 2023 +0100 |
| committer | Pierre-Clément Tosi <ptosi@google.com> | Wed Oct 11 16:54:04 2023 +0100 |
| tree | f98131a548060575351ccec043846f3531f7d5da | |
| parent | 6127032bf7a8477115afb15c66fcefe86ed3601f [diff] |
ANDROID: bazel: Clean up lexer and parser rules
Simplify the build file as
- dtc_gen creates an unnecessarily broad (and confusing) dependency list
by using glob([".h"]) as its header list. Instead, dtc now lists
explicitly the few headers it actually needs;
- generating dtc-lexer.lex.c does not require dtc-parser.{c,h};
- Bison can be told to directly create dtc-parser.{c,h} so no need for
an unnecessarily broad copying of *.[ch] to move some intermediate
results.
As a result, we get two genrule() wrapping the source files respectively
generated through lex and bison, which can be listed as srcs of dtc.
Test: bazel build //:all
Change-Id: I238d963af8a338c46f39c8ba9e4314fe536948cf
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:
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.