[PATCH 1/2] binman: Add 'min-size' entry property

[Samuel Holland]

This property sets the minimum size of an entry, including padding but
not alignment. It can be used to reserve space for growth of an entry,
or to enforce a minimum offset for later entries in the section.

Signed-off-by: Samuel Holland <samuel at sholland.org>
---

 tools/binman/binman.rst              |  8 ++++++++
 tools/binman/entry.py                |  4 ++++
 tools/binman/ftest.py                | 21 +++++++++++++++++----
 tools/binman/test/009_pack_extra.dts |  7 +++++++
 4 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/tools/binman/binman.rst b/tools/binman/binman.rst
index fa8abdcd86..03a99a19bc 100644
--- a/tools/binman/binman.rst
+++ b/tools/binman/binman.rst
@@ -615,6 +615,14 @@ size:
     this size. If this is not provided, it will be set to the size of the
     contents.
 
+min-size:
+    Sets the minimum size of the entry. This size includes explicit padding
+    ('pad-before' and 'pad-after'), but not padding added to meet alignment
+    requirements. While this does not affect the contents of the entry within
+    binman itself (the padding is performed only when its parent section is
+    assembled), the end result will be that the entry ends with the padding
+    bytes, so may grow. Defaults to 0.
+
 pad-before:
     Padding before the contents of the entry. Normally this is 0, meaning
     that the contents start at the beginning of the entry. This can be used
diff --git a/tools/binman/entry.py b/tools/binman/entry.py
index 5d8696e32a..5eacc5fa6c 100644
--- a/tools/binman/entry.py
+++ b/tools/binman/entry.py
@@ -49,6 +49,7 @@ class Entry(object):
         offset: Offset of entry within the section, None if not known yet (in
             which case it will be calculated by Pack())
         size: Entry size in bytes, None if not known
+        min_size: Minimum entry size in bytes
         pre_reset_size: size as it was before ResetForPack(). This allows us to
             keep track of the size we started with and detect size changes
         uncomp_size: Size of uncompressed data in bytes, if the entry is
@@ -114,6 +115,7 @@ class Entry(object):
         self.name = node and (name_prefix + node.name) or 'none'
         self.offset = None
         self.size = None
+        self.min_size = 0
         self.pre_reset_size = None
         self.uncomp_size = None
         self.data = None
@@ -270,6 +272,7 @@ class Entry(object):
             self.Raise("Please use 'extend-size' instead of 'expand-size'")
         self.offset = fdt_util.GetInt(self._node, 'offset')
         self.size = fdt_util.GetInt(self._node, 'size')
+        self.min_size = fdt_util.GetInt(self._node, 'min-size', 0)
         self.orig_offset = fdt_util.GetInt(self._node, 'orig-offset')
         self.orig_size = fdt_util.GetInt(self._node, 'orig-size')
         if self.GetImage().copy_to_orig:
@@ -507,6 +510,7 @@ class Entry(object):
             else:
                 self.offset = tools.align(offset, self.align)
         needed = self.pad_before + self.contents_size + self.pad_after
+        needed = max(needed, self.min_size)
         needed = tools.align(needed, self.align_size)
         size = self.size
         if not size:
diff --git a/tools/binman/ftest.py b/tools/binman/ftest.py
index be0aea49ce..93b332972a 100644
--- a/tools/binman/ftest.py
+++ b/tools/binman/ftest.py
@@ -883,9 +883,9 @@ class TestFunctional(unittest.TestCase):
         self.assertIn('image', control.images)
         image = control.images['image']
         entries = image.GetEntries()
-        self.assertEqual(5, len(entries))
+        self.assertEqual(6, len(entries))
 
-        # First u-boot with padding before and after
+        # First u-boot with padding before and after (included in minimum size)
         self.assertIn('u-boot', entries)
         entry = entries['u-boot']
         self.assertEqual(0, entry.offset)
@@ -934,8 +934,17 @@ class TestFunctional(unittest.TestCase):
         self.assertEqual(U_BOOT_DATA + tools.get_bytes(0, 64 - len(U_BOOT_DATA)),
                          data[pos:pos + entry.size])
 
+        # Sixth u-boot with both minimum size and aligned size
+        self.assertIn('u-boot-min-size', entries)
+        entry = entries['u-boot-min-size']
+        self.assertEqual(128, entry.offset)
+        self.assertEqual(32, entry.size)
+        self.assertEqual(U_BOOT_DATA, entry.data[:len(U_BOOT_DATA)])
+        self.assertEqual(U_BOOT_DATA + tools.get_bytes(0, 32 - len(U_BOOT_DATA)),
+                         data[pos:pos + entry.size])
+
         self.CheckNoGaps(entries)
-        self.assertEqual(128, image.size)
+        self.assertEqual(160, image.size)
 
         dtb = fdt.Fdt(out_dtb_fname)
         dtb.Scan()
@@ -943,7 +952,7 @@ class TestFunctional(unittest.TestCase):
         expected = {
             'image-pos': 0,
             'offset': 0,
-            'size': 128,
+            'size': 160,
 
             'u-boot:image-pos': 0,
             'u-boot:offset': 0,
@@ -964,6 +973,10 @@ class TestFunctional(unittest.TestCase):
             'u-boot-align-both:image-pos': 64,
             'u-boot-align-both:offset': 64,
             'u-boot-align-both:size': 64,
+
+            'u-boot-min-size:image-pos': 128,
+            'u-boot-min-size:offset': 128,
+            'u-boot-min-size:size': 32,
             }
         self.assertEqual(expected, props)
 
diff --git a/tools/binman/test/009_pack_extra.dts b/tools/binman/test/009_pack_extra.dts
index 1b31555771..8d6f4910c9 100644
--- a/tools/binman/test/009_pack_extra.dts
+++ b/tools/binman/test/009_pack_extra.dts
@@ -6,6 +6,7 @@
 
 	binman {
 		u-boot {
+			min-size = <12>;
 			pad-before = <3>;
 			pad-after = <5>;
 		};
@@ -31,5 +32,11 @@
 			align = <64>;
 			align-end = <128>;
 		};
+
+		u-boot-min-size {
+			type = "u-boot";
+			min-size = <24>;
+			align-size = <16>;
+		};
 	};
 };
-- 
2.37.4