binman: collection: Set build_done on referenced entries

The collection etype uses phandles in the 'content' property to
reference other entries. Mark each referenced entry with build_done
to avoid rebuilding the same entry data multiple times.

This is important for cases where rebuilding may change the data
content, e.g. due to timestamps or random IVs in encryption.

Refactor GetContentsByPhandle() to return both the entry object and
its data.

Signed-off-by: yan wang <yan.wang@softathome.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

tools/binman/etype/collection.py

@@ -45,12 +45,17 @@ class Entry_collection(Entry):
         self.Info('Getting contents, required=%s' % required)
         data = bytearray()
         for entry_phandle in self.content:
-            entry_data = self.section.GetContentsByPhandle(entry_phandle, self,
-                                                           required)
+            entry, entry_data = self.section.GetContentsByPhandle(
+                entry_phandle, self, required)
             if not required and entry_data is None:
                 self.Info('Contents not available yet')
                 # Data not available yet
                 return None
+
+            # Mark referenced entries as build_done to avoid rebuilding
+            if required:
+                entry.mark_build_done()
+
             data += entry_data
 
         self.Info('Returning contents size %x' % len(data))

tools/binman/etype/section.py

@@ -557,7 +557,8 @@ class Entry_section(Entry):
                 return None
 
         Returns:
-            data from associated entry (as a string), or None if not found
+            tuple: (entry, data) where entry is the Entry object and data is
+                from that entry (as a string), or (entry, None) if data not found
         """
         node = self._node.GetFdt().LookupPhandle(phandle)
         if not node:
@@ -565,7 +566,7 @@ class Entry_section(Entry):
         entry = self.FindEntryByNode(node)
         if not entry:
             source_entry.Raise("Cannot find entry for node '%s'" % node.name)
-        return entry.GetData(required)
+        return entry, entry.GetData(required)
 
     def LookupEntry(self, entries, sym_name, msg):
         """Look up the entry for a binman symbol