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>
This simply utility makes it easy for scripts to read values from the device
tree. It is written in C and uses the same libfdt as the rest of the dtc
package.
What is it for:
- Reading fdt values from scripts
- Extracting fdt information within build systems
- Looking at particular values without having to dump the entire tree
To use it, specify the fdt binary file on command line followed by a list of
node, property pairs. The utility then looks up each node, finds the property
and displays the value.
Each value is printed on a new line.
fdtget tries to guess the type of each property based on its contents. This
is not always reliable, so you can use the -t option to force fdtget to decode
the value as a string, or byte, etc.
To read from stdin, use - as the file.
Usage:
fdtget <options> <dt file> [<node> <property>]...
Options:
-t <type> Type of data
-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)
Signed-off-by: Simon Glass <sjg@chromium.org>
Some of the helper scripts used to run testcases contain some
constructs that are bashisms. Or at least which don't work on dash,
the minimal shell used as /bin/sh on recent Ubuntu systems.
This patch removes these constructs so that the testsuite will pass
"out of the box" on systems where /bin/sh is dash.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This patch modifies the dtc-checkfails.sh testcase wrapper so that
instead of testing just that dtc fails with a particular error code on
the sample input, it scans dtc's stderr output looking for a message
that dtc failed a specific check or checks. This has several advantages:
- It means we more precisely check dtc's checking behaviour
- It means we can check for generation of warnings using the
same script
- It means we can test cases where dtc should generate
multiple errors or warnings from different checks
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This patch adds a group of testcases to check that dtc correctly
rejects trees with various structural errors.
To make things easier to test, we change dtc so that failing checks
(as opposed to other errors) result in exit code 2.
This patch also fixes an embarrasing bug uncovered by these new tests:
check_phandles() worked out if the tree's phandles were valid, then
throws that information away and returns success always.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This patch adds a handful of simple testcases for dtc. It adds a dts
file which should generate the same sample tree as is used for the
libfdt testcases, and tests invoking dtc on this dts, plus the
standard batch of libfdt cases on the resulting dtb, which effectively
checks that the dtb is correct.
Because the test framework assumes each testcase is an executable with
the right output conventions, we use a little shell script, dtc.sh, as
a wrapper around dtc itself. It simply invokes dtc and returns a PASS
or FAIL depending on whether dtc returned an error.
It's not much, but it's a start.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Simon Glass