binman: Place Intel descriptor at image start

The Intel descriptor must always appear at the start of an (x86) image,
so it is supposed to position itself there always. However there is no
explicit test for this. Add one and fix a bug introduced by the recent
change to adjust Entry to read the node in a separate call.

Signed-off-by: Simon Glass <sjg@chromium.org>

3 files changed, 34 insertions, 1 deletions

diff --git a/tools/binman/etype/intel_descriptor.py b/tools/binman/etype/intel_descriptor.py
index adea578080..fb5e889ebf 100644
--- a/tools/binman/etype/intel_descriptor.py
+++ b/tools/binman/etype/intel_descriptor.py
@@ -47,8 +47,12 @@ class Entry_intel_descriptor(Entry_blob):
     def __init__(self, section, etype, node):
         Entry_blob.__init__(self, section, etype, node)
         self._regions = []
+
+    def Pack(self, offset):
+        """Put this entry at the start of the image"""
         if self.offset is None:
-            self.offset = self.section.GetStartOffset()
+            offset = self.section.GetStartOffset()
+        return Entry_blob.Pack(self, offset)
 
     def GetOffsets(self):
         offset = self.data.find(FD_SIGNATURE)
diff --git a/tools/binman/ftest.py b/tools/binman/ftest.py
index 11155ced70..d1ecd65c2c 100644
--- a/tools/binman/ftest.py
+++ b/tools/binman/ftest.py
@@ -2975,6 +2975,15 @@ class TestFunctional(unittest.TestCase):
         self.assertEqual(U_BOOT_DATA, data[2:2 + len(U_BOOT_DATA)])
         self.assertEqual(b'a\0', data[-2:])
 
+    def testDescriptorOffset(self):
+        """Test that the Intel descriptor is always placed at at the start"""
+        data = self._DoReadFileDtb('141_descriptor_offset.dts')
+        image = control.images['image']
+        entries = image.GetEntries()
+        desc = entries['intel-descriptor']
+        self.assertEqual(0xff800000, desc.offset);
+        self.assertEqual(0xff800000, desc.image_pos);
+
 
 if __name__ == "__main__":
     unittest.main()
diff --git a/tools/binman/test/141_descriptor_offset.dts b/tools/binman/test/141_descriptor_offset.dts
new file mode 100644
index 0000000000..f9bff016aa
--- /dev/null
+++ b/tools/binman/test/141_descriptor_offset.dts
@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+/dts-v1/;
+
+/ {
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	binman {
+		sort-by-offset;
+		end-at-4gb;
+		size = <0x800000>;
+		u-boot {
+			offset = <0xffff0000>;
+		};
+		intel-descriptor {
+			filename = "descriptor.bin";
+		};
+	};
+};