[PATCH 11/15] binman: Add minor improvements to symbol-writing

[Simon Glass]

Add a clarification to the documentation and add a missing comment. Also
update the test so that when it fails it is easier to see what is going
on, rather than having to decode hex strings.

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

 tools/binman/binman.rst |  4 +++-
 tools/binman/elf.py     |  3 ++-
 tools/binman/ftest.py   | 36 +++++++++++++++++++++++++++++-------
 3 files changed, 34 insertions(+), 9 deletions(-)

diff --git a/tools/binman/binman.rst b/tools/binman/binman.rst
index 0cafc36bdcb..04564f4f66f 100644
--- a/tools/binman/binman.rst
+++ b/tools/binman/binman.rst
@@ -494,7 +494,9 @@ point into the image.
 For example, say SPL is at the start of the image and linked to start at address
 80108000. If U-Boot's image-pos is 0x8000 then binman will write an image-pos
 for U-Boot of 80110000 into the SPL binary, since it assumes the image is loaded
-to 80108000, with SPL at 80108000 and U-Boot at 80110000.
+to 80108000, with SPL at 80108000 and U-Boot at 80110000. In other words, the
+positions are calculated relative to the start address of the image to which
+they are being written.
 
 For x86 devices (with the end-at-4gb property) this base address is not added
 since it is assumed that images are XIP and the offsets already include the
diff --git a/tools/binman/elf.py b/tools/binman/elf.py
index 1c3b1e225f4..73394830ebe 100644
--- a/tools/binman/elf.py
+++ b/tools/binman/elf.py
@@ -247,7 +247,8 @@ def LookupAndWriteSymbols(elf_fname, entry, section, is_elf=False,
             entry
         entry: Entry to process
         section: Section which can be used to lookup symbol values
-        base_sym: Base symbol marking the start of the image
+        base_sym: Base symbol marking the start of the image (__image_copy_start
+            by default)
 
     Returns:
         int: Number of symbols written
diff --git a/tools/binman/ftest.py b/tools/binman/ftest.py
index 56deece7230..9f329704115 100644
--- a/tools/binman/ftest.py
+++ b/tools/binman/ftest.py
@@ -1526,18 +1526,40 @@ class TestFunctional(unittest.TestCase):
         # The image should contain the symbols from u_boot_binman_syms.c
         # Note that image_pos is adjusted by the base address of the image,
         # which is 0x10 in our test image
-        sym_values = struct.pack('<LLQLL', elf.BINMAN_SYM_MAGIC_VALUE,
-                                 0x00, u_boot_offset + len(U_BOOT_DATA),
-                                 0x10 + u_boot_offset, 0x04)
+        vals = (elf.BINMAN_SYM_MAGIC_VALUE, 0x00,
+                u_boot_offset + len(U_BOOT_DATA),
+                0x10 + u_boot_offset, 0x04)
+        sym_values = struct.pack('<LLQLL', *vals)
         if no_write_symbols:
-            expected = (base_data +
-                        tools.get_bytes(0xff, 0x38 - len(base_data)) +
-                        U_BOOT_DATA + base_data)
+            self.assertEqual(
+                base_data +
+                tools.get_bytes(0xff, 0x38 - len(base_data)) +
+                U_BOOT_DATA + base_data, data)
         else:
+            got_vals = struct.unpack('<LLQLL', data[:24])
+
+            # For debugging:
+            #print('expect:', list(f'{v:x}' for v in vals))
+            #print('   got:', list(f'{v:x}' for v in got_vals))
+
+            self.assertEqual(vals, got_vals)
+            self.assertEqual(sym_values, data[:24])
+
+            blen = len(base_data)
+            self.assertEqual(base_data[24:], data[24:blen])
+            self.assertEqual(0xff, data[blen])
+
+            ofs = blen + 1 + len(U_BOOT_DATA)
+            self.assertEqual(U_BOOT_DATA, data[blen + 1:ofs])
+
+            self.assertEqual(sym_values, data[ofs:ofs + 24])
+            self.assertEqual(base_data[24:], data[ofs + 24:])
+
+            # Just repeating the above asserts all at once, for clarity
             expected = (sym_values + base_data[24:] +
                         tools.get_bytes(0xff, 1) + U_BOOT_DATA + sym_values +
                         base_data[24:])
-        self.assertEqual(expected, data)
+            self.assertEqual(expected, data)
 
     def testSymbols(self):
         """Test binman can assign symbols embedded in U-Boot"""
-- 
2.34.1