binman: Record the parent section of each section

[oweals/u-boot.git] / tools / binman / etype / u_boot_spl_bss_pad.py

diff --git a/tools/binman/etype/u_boot_spl_bss_pad.py b/tools/binman/etype/u_boot_spl_bss_pad.py
index c37f61db23553de720f2659714c3409f4dd1798f..00b7ac50040ef752a11f9705bbc493690e167127 100644 (file)
--- a/tools/binman/etype/u_boot_spl_bss_pad.py
+++ b/tools/binman/etype/u_boot_spl_bss_pad.py
@@ -1,8 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0+
 # Copyright (c) 2016 Google, Inc
 # Written by Simon Glass <sjg@chromium.org>
 #
-# SPDX-License-Identifier:      GPL-2.0+
-#
 # Entry-type module for BSS padding for spl/u-boot-spl.bin. This padding
 # can be added after the SPL binary to ensure that anything concatenated
 # to it will appear to SPL to be at the end of BSS rather than the start.
@@ -15,13 +14,29 @@ from blob import Entry_blob
 import tools
 
 class Entry_u_boot_spl_bss_pad(Entry_blob):
-    def __init__(self, image, etype, node):
-        Entry_blob.__init__(self, image, etype, node)
+    """U-Boot SPL binary padded with a BSS region
+
+    Properties / Entry arguments:
+        None
+
+    This is similar to u_boot_spl except that padding is added after the SPL
+    binary to cover the BSS (Block Started by Symbol) region. This region holds
+    the various used by SPL. It is set to 0 by SPL when it starts up. If you
+    want to append data to the SPL image (such as a device tree file), you must
+    pad out the BSS region to avoid the data overlapping with U-Boot variables.
+    This entry is useful in that case. It automatically pads out the entry size
+    to cover both the code, data and BSS.
+
+    The ELF file 'spl/u-boot-spl' must also be available for this to work, since
+    binman uses that to look up the BSS address.
+    """
+    def __init__(self, section, etype, node):
+        Entry_blob.__init__(self, section, etype, node)
 
     def ObtainContents(self):
         fname = tools.GetInputFilename('spl/u-boot-spl')
         bss_size = elf.GetSymbolAddress(fname, '__bss_size')
         if not bss_size:
             self.Raise('Expected __bss_size symbol in spl/u-boot-spl')
-        self.data = chr(0) * bss_size
-        self.contents_size = bss_size
+        self.SetContents(chr(0) * bss_size)
+        return True