[RFC PATCH v2 65/74] tests: Add a first basic test for fdtaddon

[Herve Codina <herve.codina@bootlin.com>]

The fdtaddon tests family goal is to test features related the
application of an addon to a base device tree.

This first basic test added in fdtaddon tests is related to the
application of a simple addon.

The terminology used in the test is the following:
  - dts: A 'full' device tree source.
    This can be either a base device tree or a merged device tree (i.e. a
    base device tree where an addon has been applied to).

  - dtb: A 'full' device tree blob
    This can be either a dtb generated by dtc from a dts or the output of
    the fdtaddon command.

  - dtsa: An addon device tree source
    A dts with the '/addon/' keyword.

  - dtba: An addon device tree blob
    This a device tree blob generated from a dtsa.

With this terminology in mind, the test pattern is the following:
  - Generate the base tree dtb (fdtaddon_base.dtb)
  - Check this generated dtb against expected contents
  - Generate a dtba (xxx.dtba) from an input dtsa
  - Check this generated dtba against expected contents
  - Apply the dtba to the base tree dtb at node-a1 (xxx-merged1.dtb)
  - Check this generated dtb against expected contents
  - Generate a dts (xxx-merged1.dtb.dts) from the generated xxx-merged1.dtb
  - Check this generated dts against expected contents
  - Apply the dtba to the base tree dtb at node-a2 (xxx-merged2.dtb)
  - Check this generated dtb against expected contents
  - Generate a dts (xxx-merged2.dtb.dts) from the generated xxx-merged2.dtb
  - Check this generated dts against expected contents

Even if only one basic addon dsta is currently provided in this tests
introduction, use a loop in order to ease future addition consisting in
testing other features based on more complex addon dtsa.

Signed-off-by: Herve Codina <herve.codina@bootlin.com>
---
 tests/fdtaddon_base.dtb.expect                | 24 ++++++++++
 tests/fdtaddon_base.dts                       | 27 +++++++++++
 tests/fdtaddon_basics1-merged1.dtb.dts.expect | 35 ++++++++++++++
 tests/fdtaddon_basics1-merged1.dtb.expect     | 27 +++++++++++
 tests/fdtaddon_basics1-merged2.dtb.dts.expect | 35 ++++++++++++++
 tests/fdtaddon_basics1-merged2.dtb.expect     | 27 +++++++++++
 tests/fdtaddon_basics1.dtba.expect            |  8 ++++
 tests/fdtaddon_basics1.dtsa                   | 13 +++++
 tests/meson.build                             |  1 +
 tests/run_tests.sh                            | 47 ++++++++++++++++++-
 tests/testutils.sh                            |  1 +
 11 files changed, 244 insertions(+), 1 deletion(-)
 create mode 100644 tests/fdtaddon_base.dtb.expect
 create mode 100644 tests/fdtaddon_base.dts
 create mode 100644 tests/fdtaddon_basics1-merged1.dtb.dts.expect
 create mode 100644 tests/fdtaddon_basics1-merged1.dtb.expect
 create mode 100644 tests/fdtaddon_basics1-merged2.dtb.dts.expect
 create mode 100644 tests/fdtaddon_basics1-merged2.dtb.expect
 create mode 100644 tests/fdtaddon_basics1.dtba.expect
 create mode 100644 tests/fdtaddon_basics1.dtsa

diff --git a/tests/fdtaddon_base.dtb.expect b/tests/fdtaddon_base.dtb.expect
new file mode 100644
index 00000000..2da5be4d
--- /dev/null
+++ b/tests/fdtaddon_base.dtb.expect
@@ -0,0 +1,24 @@
+/dts-v1/;
+
+/ {
+    base-node {
+        sub-node {
+            prop = <0x00000000>;
+            phandle = <0x00000002>;
+        };
+    };
+    somewhere {
+        node-a1 {
+            // [FDT_EXPORT_SYM] 'node_a' -> phandle 0x00000001
+            // [FDT_EXPORT_SYM] 'other' -> phandle 0x00000002
+            compatible = "abc,aaa";
+            phandle = <0x00000001>;
+        };
+        node-a2 {
+            // [FDT_EXPORT_SYM] 'node_a' -> phandle 0x00000003
+            // [FDT_EXPORT_SYM] 'other' -> phandle 0x00000002
+            compatible = "abc,aaa";
+            phandle = <0x00000003>;
+        };
+    };
+};
diff --git a/tests/fdtaddon_base.dts b/tests/fdtaddon_base.dts
new file mode 100644
index 00000000..3b001461
--- /dev/null
+++ b/tests/fdtaddon_base.dts
@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
+/*
+ * Copyright (C) 2026 Bootlin
+ */
+
+/dts-v1/;
+
+/ {
+	base-node {
+		other_a: sub-node {
+			prop = <0>;
+		};
+	};
+
+	somewhere {
+		node_a1: node-a1 {
+			compatible = "abc,aaa";
+			/export/ node_a: &node_a1;
+			/export/ other: &other_a;
+		};
+		node_a2: node-a2 {
+			compatible = "abc,aaa";
+			/export/ node_a: &node_a2;
+			/export/ other: &other_a;
+		};
+	};
+};
diff --git a/tests/fdtaddon_basics1-merged1.dtb.dts.expect b/tests/fdtaddon_basics1-merged1.dtb.dts.expect
new file mode 100644
index 00000000..927733c1
--- /dev/null
+++ b/tests/fdtaddon_basics1-merged1.dtb.dts.expect
@@ -0,0 +1,35 @@
+/dts-v1/;
+
+/ {
+
+	base-node {
+
+		sub-node {
+			prop = <0x00>;
+			phandle = <0x02>;
+		};
+	};
+
+	somewhere {
+
+		node-a1 {
+			compatible = "abc,aaa";
+			phandle = <0x01>;
+
+			/export/ node_a: &{/somewhere/node-a1};
+			/export/ other: &{/base-node/sub-node};
+
+			addon-node {
+				prop = <0x00>;
+			};
+		};
+
+		node-a2 {
+			compatible = "abc,aaa";
+			phandle = <0x03>;
+
+			/export/ node_a: &{/somewhere/node-a2};
+			/export/ other: &{/base-node/sub-node};
+		};
+	};
+};
diff --git a/tests/fdtaddon_basics1-merged1.dtb.expect b/tests/fdtaddon_basics1-merged1.dtb.expect
new file mode 100644
index 00000000..966a43df
--- /dev/null
+++ b/tests/fdtaddon_basics1-merged1.dtb.expect
@@ -0,0 +1,27 @@
+/dts-v1/;
+
+/ {
+    base-node {
+        sub-node {
+            prop = <0x00000000>;
+            phandle = <0x00000002>;
+        };
+    };
+    somewhere {
+        node-a1 {
+            // [FDT_EXPORT_SYM] 'node_a' -> phandle 0x00000001
+            // [FDT_EXPORT_SYM] 'other' -> phandle 0x00000002
+            compatible = "abc,aaa";
+            phandle = <0x00000001>;
+            addon-node {
+                prop = <0x00000000>;
+            };
+        };
+        node-a2 {
+            // [FDT_EXPORT_SYM] 'node_a' -> phandle 0x00000003
+            // [FDT_EXPORT_SYM] 'other' -> phandle 0x00000002
+            compatible = "abc,aaa";
+            phandle = <0x00000003>;
+        };
+    };
+};
diff --git a/tests/fdtaddon_basics1-merged2.dtb.dts.expect b/tests/fdtaddon_basics1-merged2.dtb.dts.expect
new file mode 100644
index 00000000..d85567b7
--- /dev/null
+++ b/tests/fdtaddon_basics1-merged2.dtb.dts.expect
@@ -0,0 +1,35 @@
+/dts-v1/;
+
+/ {
+
+	base-node {
+
+		sub-node {
+			prop = <0x00>;
+			phandle = <0x02>;
+		};
+	};
+
+	somewhere {
+
+		node-a1 {
+			compatible = "abc,aaa";
+			phandle = <0x01>;
+
+			/export/ node_a: &{/somewhere/node-a1};
+			/export/ other: &{/base-node/sub-node};
+		};
+
+		node-a2 {
+			compatible = "abc,aaa";
+			phandle = <0x03>;
+
+			/export/ node_a: &{/somewhere/node-a2};
+			/export/ other: &{/base-node/sub-node};
+
+			addon-node {
+				prop = <0x00>;
+			};
+		};
+	};
+};
diff --git a/tests/fdtaddon_basics1-merged2.dtb.expect b/tests/fdtaddon_basics1-merged2.dtb.expect
new file mode 100644
index 00000000..ca9c7ba0
--- /dev/null
+++ b/tests/fdtaddon_basics1-merged2.dtb.expect
@@ -0,0 +1,27 @@
+/dts-v1/;
+
+/ {
+    base-node {
+        sub-node {
+            prop = <0x00000000>;
+            phandle = <0x00000002>;
+        };
+    };
+    somewhere {
+        node-a1 {
+            // [FDT_EXPORT_SYM] 'node_a' -> phandle 0x00000001
+            // [FDT_EXPORT_SYM] 'other' -> phandle 0x00000002
+            compatible = "abc,aaa";
+            phandle = <0x00000001>;
+        };
+        node-a2 {
+            // [FDT_EXPORT_SYM] 'node_a' -> phandle 0x00000003
+            // [FDT_EXPORT_SYM] 'other' -> phandle 0x00000002
+            compatible = "abc,aaa";
+            phandle = <0x00000003>;
+            addon-node {
+                prop = <0x00000000>;
+            };
+        };
+    };
+};
diff --git a/tests/fdtaddon_basics1.dtba.expect b/tests/fdtaddon_basics1.dtba.expect
new file mode 100644
index 00000000..1102923a
--- /dev/null
+++ b/tests/fdtaddon_basics1.dtba.expect
@@ -0,0 +1,8 @@
+/dts-v1/;
+/addon/;
+
+/ {
+    addon-node {
+        prop = <0x00000000>;
+    };
+};
diff --git a/tests/fdtaddon_basics1.dtsa b/tests/fdtaddon_basics1.dtsa
new file mode 100644
index 00000000..84621c97
--- /dev/null
+++ b/tests/fdtaddon_basics1.dtsa
@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
+/*
+ * Copyright (C) 2026 Bootlin
+ */
+
+/dts-v1/;
+/addon/;
+
+/ {
+	addon-node {
+		prop = <0>;
+	};
+};
diff --git a/tests/meson.build b/tests/meson.build
index ec24f0af..e1a2454e 100644
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -144,6 +144,7 @@ run_test_types = [
   'fdtdump',
   'fdtoverlay',
   'metadata',
+  'fdtaddon',
 ]
 run_test_deps = [
   dtc_tools, treegen_dtb, tests_exe,
diff --git a/tests/run_tests.sh b/tests/run_tests.sh
index 7f47b685..3f80b183 100755
--- a/tests/run_tests.sh
+++ b/tests/run_tests.sh
@@ -1281,6 +1281,48 @@ metadata_tests() {
 	run_test check_full metadata_sort.dtb
 }
 
+run_fdtaddon_test () {
+	printf "fdtaddon $*:	"
+	base_run_test wrap_test $VALGRIND $FDTADDON "$@"
+}
+
+check_dtb () {
+	local dtb="$1"
+	base_run_test wrap_fdtdump "$dtb" "$dtb.out"
+	sed -i '/^\/\/ [^\[]/d' "$dtb.out"
+	base_run_test check_diff "$dtb.out" "$SRCDIR/$dtb.expect"
+	run_test check_full "$dtb"
+}
+
+check_dts () {
+	local dts="$1"
+	base_run_test check_diff "$dts" "$SRCDIR/$dts.expect"
+}
+
+fdtaddon_tests() {
+	run_dtc_test -I dts -O dtb -o fdtaddon_base.dtb "$SRCDIR/fdtaddon_base.dts"
+	check_dtb fdtaddon_base.dtb
+
+	for dt in fdtaddon_basics1; do
+		run_dtc_test -I dts -O dtb -o $dt.dtba "$SRCDIR/$dt.dtsa"
+		check_dtb $dt.dtba
+
+		run_fdtaddon_test -i fdtaddon_base.dtb -o $dt-merged1.dtb \
+				  -t "/somewhere/node-a1" $dt.dtba
+		check_dtb $dt-merged1.dtb
+
+		run_dtc_test -I dtb -O dts -o $dt-merged1.dtb.dts $dt-merged1.dtb
+		check_dts $dt-merged1.dtb.dts
+
+		run_fdtaddon_test -i fdtaddon_base.dtb -o $dt-merged2.dtb \
+				  -t "/somewhere/node-a2" $dt.dtba
+		check_dtb $dt-merged2.dtb
+
+		run_dtc_test -I dtb -O dts -o $dt-merged2.dtb.dts $dt-merged2.dtb
+		check_dts $dt-merged2.dtb.dts
+	done
+}
+
 pylibfdt_tests () {
     run_dtc_test -I dts -O dtb -o test_props.dtb "$SRCDIR/test_props.dts"
     TMP=/tmp/tests.stderr.$$
@@ -1320,7 +1362,7 @@ while getopts "vt:me" ARG ; do
 done
 
 if [ -z "$TESTSETS" ]; then
-    TESTSETS="libfdt utilfdt dtc dtbs_equal fdtget fdtput fdtdump fdtoverlay metadata"
+    TESTSETS="libfdt utilfdt dtc dtbs_equal fdtget fdtput fdtdump fdtoverlay metadata fdtaddon"
 
     # Test pylibfdt if the libfdt Python module is available.
     if ! $no_python; then
@@ -1363,6 +1405,9 @@ for set in $TESTSETS; do
 	"metadata")
 	    metadata_tests
 	    ;;
+	"fdtaddon")
+	    fdtaddon_tests
+	    ;;
     esac
 done
 
diff --git a/tests/testutils.sh b/tests/testutils.sh
index 6b2f0d14..b5e121e7 100644
--- a/tests/testutils.sh
+++ b/tests/testutils.sh
@@ -27,6 +27,7 @@ DTGET=${TEST_BINDIR}/fdtget
 DTPUT=${TEST_BINDIR}/fdtput
 FDTDUMP=${TEST_BINDIR}/fdtdump
 FDTOVERLAY=${TEST_BINDIR}/fdtoverlay
+FDTADDON=${TEST_BINDIR}/fdtaddon
 
 verbose_run () {
     if [ -z "$QUIET_TEST" ]; then
-- 
2.55.0