STM32H7Sx - Use HDPL_x DHUK within HDPL_y where x > y

[Eliasvan]

Dear,

Is it possible for execution within HDPL_x to use SAES (Secure AES) with a DHUK (Derived Hardware Unique Key) from HDPL_y where x > y?

For example:

1. Execution within HDPL2 makes use of SAES to encrypt plaintext p using its DHUK, this results in ciphertext c
2. Afterwards, upon reset, execution within HDPL1 needs to be able to read plaintext p (e.g., by decrypting the stored ciphertext c using HDPL2's DHUK) without changing the HDPL.
   Is this possible with SAES, and if yes, how?

Thanks a lot!