AES_MR
mr = atmel_aes_read(dd, AES_MR);
atmel_aes_write(dd, AES_MR, mr);
case AES_MR:
atmel_aes_write(dd, AES_MR, 0xE << AES_MR_CKEY_OFFSET);
atmel_aes_write(dd, AES_MR, valmr);