doc: signature: describe how to enable ECDSA

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Reviewed-by: Simon Glass <sjg@chromium.org>

diff --git a/doc/uImage.FIT/signature.txt b/doc/uImage.FIT/signature.txt
index b6707417ff63dce70749a6ea2662eb5793684a95..240244b30e6302af254fddcb5b160c0b4b11cac3 100644 (file)
--- a/doc/uImage.FIT/signature.txt
+++ b/doc/uImage.FIT/signature.txt
@@ -439,6 +439,7 @@ be enabled:
 
 CONFIG_FIT_SIGNATURE - enable signing and verification in FITs
 CONFIG_RSA - enable RSA algorithm for signing
+CONFIG_ECDSA - enable ECDSA algorithm for signing
 
 WARNING: When relying on signed FIT images with required signature check
 the legacy image format is default disabled by not defining