mirror of
https://github.com/dgibson/dtc.git
synced 2026-01-22 01:30:34 -05:00
Mirror of DTC
1ede50c355
This simple utility allows writing of values into a device tree from the
command line. It aimes to be the opposite of fdtget.
What is it for:
- Updating fdt values when a binary blob already exists
(even though source may be available it might be easier to use this
utility rather than sed, etc.)
- Writing machine-specific fdt values within a build system
To use it, specify the fdt binary file on command line followed by the node
and property to set. Then, provide a list of values to put into that
property. Often there will be just one, but fdtput also supports arrays and
string lists.
fdtput does not try to guess the type of the property based on looking at
the arguments. Instead it always assumes that an integer is provided. To
indicate that you want to write a string, use -ts. You can also provide
hex values with -tx.
The command line arguments are joined together into a single value. For
strings, a nul terminator is placed between each string when it is packed
into the property. To avoid this, pass the string as a single argument.
Usage:
fdtput <options> <dt file> <<node> <property> [<value>...]
Options:
-t <type> Type of data
-v Verbose: display each value decoded from command line
-h Print this help
<type> s=string, i=int, u=unsigned, x=hex
Optional modifier prefix:
hh or b=byte, h=2 byte, l=4 byte (default)
To read from stdin and write to stdout, use - as the file. So you can do:
cat somefile.dtb | fdtput -ts - /node prop "My string value" > newfile.dtb
This commit also adds basic tests to verify the major features.
Signed-off-by: Simon Glass <sjg@chromium.org>
|
||
|---|---|---|
| Documentation | ||
| libfdt | ||
| scripts | ||
| tests | ||
| .gitignore | ||
| checks.c | ||
| convert-dtsv0-lexer.l | ||
| data.c | ||
| dtc-lexer.l | ||
| dtc-parser.y | ||
| dtc.c | ||
| dtc.h | ||
| dtdiff | ||
| fdtdump.c | ||
| fdtget.c | ||
| fdtput.c | ||
| flattree.c | ||
| fstree.c | ||
| GPL | ||
| livetree.c | ||
| Makefile | ||
| Makefile.convert-dtsv0 | ||
| Makefile.dtc | ||
| Makefile.utils | ||
| README.license | ||
| srcpos.c | ||
| srcpos.h | ||
| TODO | ||
| treesource.c | ||
| util.c | ||
| util.h | ||
Licensing and contribution policy of dtc and libfdt =================================================== This dtc package contains two pieces of software: dtc itself, and libfdt which comprises the files in the libfdt/ subdirectory. These two pieces of software, although closely related, are quite distinct. dtc does not incoporate or rely on libfdt for its operation, nor vice versa. It is important that these two pieces of software have different license conditions. As the copyright banners in each source file attest, dtc is licensed under the GNU GPL. The full text of the GPL can be found in the file entitled 'GPL' which should be included in this package. dtc code, therefore, may not be incorporated into works which do not have a GPL compatible license. libfdt, however, is GPL/BSD dual-licensed. That is, it may be used either under the terms of the GPL, or under the terms of the 2-clause BSD license (aka the ISC license). The full terms of that license are given in the copyright banners of each of the libfdt source files. This is, in practice, equivalent to being BSD licensed, since the terms of the BSD license are strictly more permissive than the GPL. I made the decision to license libfdt in this way because I want to encourage widespread and correct usage of flattened device trees, including by proprietary or otherwise GPL-incompatible firmware or tools. Allowing libfdt to be used under the terms of the BSD license makes that it easier for vendors or authors of such software to do so. This does mean that libfdt code could be "stolen" - say, included in a proprietary fimware and extended without contributing those extensions back to the libfdt mainline. While I hope that doesn't happen, I believe the goal of allowing libfdt to be widely used is more important than avoiding that. libfdt is quite small, and hardly rocket science; so the incentive for such impolite behaviour is small, and the inconvenience caused therby is not dire. Licenses such as the LGPL which would allow code to be used in non-GPL software, but also require contributions to be returned were considered. However, libfdt is designed to be used in firmwares and other environments with unusual technical constraints. It's difficult to anticipate all possible changes which might be needed to meld libfdt into such environments and so difficult to suitably word a license that puts the boundary between what is and isn't permitted in the intended place. Again, I judged encouraging widespread use of libfdt by keeping the license terms simple and familiar to be the more important goal. **IMPORTANT** It's intended that all of libfdt as released remain permissively licensed this way. Therefore only contributions which are released under these terms can be merged into the libfdt mainline. David Gibson <david@gibson.dropbear.id.au> (principal original author of dtc and libfdt) 2 November 2007