[PATCH 2/3] binman: add documentation for binman sign option

[Ivan Mikhaylov]

Add the documentation about binman sign option and providing an
example.

Signed-off-by: Ivan Mikhaylov <ivan.mikhaylov at siemens.com>
---
 tools/binman/binman.rst | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/tools/binman/binman.rst b/tools/binman/binman.rst
index 771645380e..efa3321b95 100644
--- a/tools/binman/binman.rst
+++ b/tools/binman/binman.rst
@@ -1005,6 +1005,16 @@ You can also replace just a selection of entries::
 
     $ binman replace -i image.bin "*u-boot*" -I indir
 
+Signing FIT with private key in an image
+---------------------------
+
+If your firmware image contains a FIT container you can sign container in
+place. For example::
+
+    $ binman sign -i image.bin -k privatekey -a sha256,rsa4096 -f fit.fit fit
+
+which will sign the FIT's content with private key and replace it immediately
+inside your image.
 
 Logging
 -------
-- 
2.35.1