The message FIFO is empty. This interrupt is raised only if the message FIFO is actually writable by software, i.e., if all of the following conditions are met: i) The KMAC block is not exercised by a hardware application interface. ii) The SHA3 block is in the Absorb state. iii) Software has not yet written the Process command to finish the absorption process. For the interrupt to be raised, the message FIFO must also have been full previously. Otherwise, the hardware empties the FIFO faster than software can fill it and there is no point in interrupting the software to inform it about the message FIFO being empty.
kmac_err
Event
KMAC/SHA3 error occurred. ERR_CODE register shows the details
Alert for KMAC operation error. It occurs when the shadow registers have update errors.
fatal_fault_err
This fatal alert is triggered when a fatal error is detected inside the KMAC unit. Examples for such faults include: i) TL-UL bus integrity fault. ii) Storage errors in the shadow registers. iii) Errors in the message, round, or key counter. iv) Any internal FSM entering an invalid state. v) An error in the redundant lfsr. The KMAC unit cannot recover from such an error and needs to be reset.
