dtoc: Support deleting a node

Add a function to delete a node. This is synced to the tree when
requested.

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

tools/dtoc/fdt.py

@@ -548,6 +548,23 @@ class Node:
         self.subnodes.append(subnode)
         return subnode
 
+    def Delete(self):
+        """Delete a node
+
+        The node is deleted and the offset cache is invalidated.
+
+        Args:
+            node (Node): Node to delete
+
+        Raises:
+            ValueError if the node does not exist
+        """
+        CheckErr(self._fdt._fdt_obj.del_node(self.Offset()),
+                 "Node '%s': delete" % self.path)
+        parent = self.parent
+        self._fdt.Invalidate()
+        parent.subnodes.remove(self)
+
     def Sync(self, auto_resize=False):
         """Sync node changes back to the device tree
 

tools/dtoc/test_fdt.py

@@ -539,6 +539,15 @@ class TestProp(unittest.TestCase):
         data = self.fdt.getprop(self.node.Offset(), 'stringlist')
         self.assertEqual(b'123\x00456\0', data)
 
+    def test_delete_node(self):
+        """Test deleting a node"""
+        old_offset = self.fdt.path_offset('/spl-test')
+        self.assertGreater(old_offset, 0)
+        self.node.Delete()
+        self.dtb.Sync()
+        new_offset = self.fdt.path_offset('/spl-test', libfdt.QUIET_NOTFOUND)
+        self.assertEqual(-libfdt.NOTFOUND, new_offset)
+
     def testFromData(self):
         dtb2 = fdt.Fdt.FromData(self.dtb.GetContents())
         self.assertEqual(dtb2.GetContents(), self.dtb.GetContents())