binman: Allow creation of entry documentation

Binman supports quite a number of different entries now. The operation of
these is not always obvious but at present the source code is the only
reference for understanding how an entry works.

Add a way to create documentation (from the source code) which can be put
in a new 'README.entries' file.

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

tools/binman/ftest.py

@@ -21,6 +21,7 @@ import control
 import elf
 import fdt
 import fdt_util
+import test_util
 import tools
 import tout
 
@@ -1177,6 +1178,20 @@ class TestFunctional(unittest.TestCase):
                     TEXT_DATA3 + 'some text')
         self.assertEqual(expected, data)
 
+    def testEntryDocs(self):
+        """Test for creation of entry documentation"""
+        with test_util.capture_sys_output() as (stdout, stderr):
+            control.WriteEntryDocs(binman.GetEntryModules())
+        self.assertTrue(len(stdout.getvalue()) > 0)
+
+    def testEntryDocsMissing(self):
+        """Test handling of missing entry documentation"""
+        with self.assertRaises(ValueError) as e:
+            with test_util.capture_sys_output() as (stdout, stderr):
+                control.WriteEntryDocs(binman.GetEntryModules(), 'u_boot')
+        self.assertIn('Documentation is missing for modules: u_boot',
+                      str(e.exception))
+
 
 if __name__ == "__main__":
     unittest.main()