Add crypto library required by signing algo
@@ -23,7 +23,13 @@ About this release:
- An overwrite only which upgrades slot 0 with the image in slot 1.
- A swapping upgrade which enables image test, allowing for rollback to a
previous known good image.
-* Supports both mbed-TLS and tinycrypt as backend crypto libraries.
+* Supports both mbed-TLS and tinycrypt as backend crypto libraries. One of them
+ must be defined and the chosen signing algorithm will require a particular
+ library according to this list:
+ - RSA 2048 needs mbed TLS
+ - ECDSA secp224r1 needs mbed TLS
+ - ECDSA secp256r1 needs tinycrypt as well as the ASN.1 code from mbed TLS
+ (so still needs that present).
Known issues:
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