7.3.4.8 Protocol Layers Improved Performances
The SHA can be tightly coupled to the AES module to improve performances when processing protocol layers such as IPsec or OpenSSL.
When the AES is configured to be tightly coupled to SHA (AES_MR), SHA must be always configured in Double Buffer mode (SHA_MR.DUALBUFF = 1).
Refer to the section “Advanced Encryption Standard (AES)” for details.