Add fdtget utility to read property values from a device tree
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>
diff --git a/tests/fdtget-runtest.sh b/tests/fdtget-runtest.sh
new file mode 100755
index 0000000..f38184f
--- /dev/null
+++ b/tests/fdtget-runtest.sh
@@ -0,0 +1,35 @@
+#! /bin/sh
+
+. ./tests.sh
+
+LOG="tmp.log.$$"
+EXPECT="tmp.expect.$$"
+
+rm -f $TMPFILE $LOG
+
+expect="$1"
+echo "$expect" >$EXPECT
+shift
+
+verbose_run_log "$LOG" $VALGRIND "$DTGET" "$@"
+ret="$?"
+
+if [ "$ret" -ne 0 -a "$expect" = "ERR" ]; then
+ PASS
+fi
+
+if [ "$ret" -gt 127 ]; then
+ signame=$(kill -l $[ret - 128])
+ FAIL "Killed by SIG$signame"
+fi
+
+diff $EXPECT $LOG
+ret="$?"
+
+rm -f $LOG $EXPECT
+
+if [ "$ret" -eq 0 ]; then
+ PASS
+else
+ FAIL
+fi
diff --git a/tests/run_tests.sh b/tests/run_tests.sh
index e42154b..e6184df 100755
--- a/tests/run_tests.sh
+++ b/tests/run_tests.sh
@@ -83,6 +83,13 @@
run_wrap_test asm_to_so "$@"
}
+run_fdtget_test () {
+ # run_fdtget_test name expected_output dtb_file args...
+ echo -n "$1: "
+ shift
+ base_run_test sh fdtget-runtest.sh "$@"
+}
+
tree1_tests () {
TREE=$1
@@ -402,6 +409,37 @@
cmp_tests test_tree1.dtb $WRONG_TREE1
}
+fdtget_tests () {
+ file=label01.dtb
+ $DTC -O dtb -o $file ${file%.dtb}.dts 2>/dev/null
+
+ # run_fdtget_test <test-name> <expected-result> <args>...
+ run_fdtget_test "Simple string" "MyBoardName" $file / model
+ run_fdtget_test "Multiple string i" "77 121 66 111 \
+97 114 100 78 97 109 101 0 77 121 66 111 97 114 100 70 97 109 105 \
+108 121 78 97 109 101 0" $file / compatible
+ run_fdtget_test "Multiple string s" "MyBoardName MyBoardFamilyName" \
+ -t s $file / compatible
+ run_fdtget_test "Integer" "32768" $file /cpus/PowerPC,970@1 d-cache-size
+ run_fdtget_test "Integer hex" "8000" -tx $file \
+ /cpus/PowerPC,970@1 d-cache-size
+ run_fdtget_test "Integer list" "61 62 63 0" -tbx $file \
+ /randomnode tricky1
+ run_fdtget_test "Byte list short" "a b c d de ea ad be ef" -tbx \
+ $file /randomnode blob
+
+ # Here the property size is not a multiple of 4 bytes, so it should fail
+ run_fdtget_test "Integer list invalid" ERR -tlx \
+ $file /randomnode mixed
+ run_fdtget_test "Integer list halfword" "6162 6300 1234 0 a 0 b 0 c" -thx \
+ $file /randomnode mixed
+ run_fdtget_test "Integer list byte" \
+ "61 62 63 0 12 34 0 0 0 a 0 0 0 b 0 0 0 c" -thhx \
+ $file /randomnode mixed
+ run_fdtget_test "Missing property" ERR -ts \
+ $file /randomnode doctor-who
+}
+
utilfdt_tests () {
run_test utilfdt_test
}
@@ -421,7 +459,7 @@
done
if [ -z "$TESTSETS" ]; then
- TESTSETS="libfdt utilfdt dtc dtbs_equal"
+ TESTSETS="libfdt utilfdt dtc dtbs_equal fdtget"
fi
# Make sure we don't have stale blobs lying around
@@ -441,6 +479,9 @@
"dtbs_equal")
dtbs_equal_tests
;;
+ "fdtget")
+ fdtget_tests
+ ;;
esac
done
diff --git a/tests/tests.sh b/tests/tests.sh
index 30ffead..d9a0524 100644
--- a/tests/tests.sh
+++ b/tests/tests.sh
@@ -11,6 +11,7 @@
}
DTC=../dtc
+DTGET=../fdtget
verbose_run () {
if [ -z "$QUIET_TEST" ]; then