binman: Provide general support for updating ELF symbols

The current support for updating variables in a binary is hard-coded to
work with U-Boot:

- It assumes the image starts at __image_copy_start
- It uses the existing U-Boot-specific entry types

It is useful for other projects to use these feature.

Add properties to enable writing symbols for any blob, a way of specifying
the base symbol and a way of providing the ELF filename to allow symbol
lookup to take place.

With this it is possible to update a Zephyr image, such as zephyr.bin
after it has been built.

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

1 files changed, 20 insertions, 0 deletions

diff --git a/tools/binman/test/blob_syms.c b/tools/binman/test/blob_syms.c
new file mode 100644
index 0000000000..d652c79aa9
--- /dev/null
+++ b/tools/binman/test/blob_syms.c
@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2017 Google, Inc
+ *
+ * Simple program to create some binman symbols. This is used by binman tests.
+ */
+
+typedef unsigned long ulong;
+
+#include <linux/kconfig.h>
+#include <binman_sym.h>
+
+DECLARE_BINMAN_MAGIC_SYM;
+
+unsigned long val1 = 123;
+unsigned long val2 = 456;
+binman_sym_declare(unsigned long, inset, offset);
+unsigned long val3 = 789;
+unsigned long val4 = 999;
+binman_sym_declare(unsigned long, inset, size);