42.6.3.1.5 Tag Generation

  • Configure CTRLA
    1. Set CTRLA.ENABLE to 0
    2. Set CTRLA.AESMODE as CTR
    3. Set CTRLA.ENABLE to 1
  • Load J0 value to INITVECTV reg.
  • Load GHASH value to INDATA reg.
  • Set CTRLB.NEWMSG and CTRLB.START to start the Counter mode operation.
  • Wait for INTFLAG.ENCCMP to be set.
  • AES Hardware generates the GCM Tag output in INDATA register.