SPRUIU1C July 2020 – February 2024 DRA821U , DRA821U-Q1
The SBL must always be signed with a given OpenSSL key - Secure and GP devices. Secure must have encryption and authentication, GP device must only have authentication. The key used for authentication can be random or specific. If a random key is generated and SBL is signed with this,the ROM will copy the SBL image for authentication using memcopy. With this key, ROM code will be directed to use DMA to load the SBL for authentication which saves boot time.