I'm running a basic firmware containing a plaintext block and a ciphertext block on my iMX RT1062 which still runs in open configuration. The ciphertext block is calculated from the plaintext block externally using a cetain key. I successfully programmend the same key to SW_GP2 fuses.
Now the SW_GP2 can be used from BEE as well as DCP. When used from BEE the read access to the ciphertext block is successfully decrypted matching the plaintext block. Now, when used from DCP, the actual key value used is 0.
So it seams SW_GP2 cannot be used currently from DCP. When instead I use the same key via Registers I can encrypt/decrypt successfully as expected via DCP..
The question here is:
- What makes the DCP not using SW_GP2 but instead using a value of 0 as the key?
- Is it due to the fact, that SW_GP2 is not yet locked or is it because the device runs in open configuration?
