SPRUJB6B November 2024 – May 2025 AM2612
The Global Control FSM and DMA I/O block contains the DMA Registers used to control the DMA request signals and context switching between two register banks for the AES Wide-bus Engine.
The FSM controls the context and data interrupts and DMA requests, according to the selected protocol and requirements to save TAG and/or IV. The FSM also controls output buffer stalling and associated overflow buffer. One additional data out buffer is available to prevent engine stalling when one HIB does not read its result data. Therefore, if both HIBs do not read their result data when both HIB output buffers are filled, the engine will stall.
Although the DMA request logic is mainly controlled by the AES Wide-bus Engine, this logic block assures that after being asserted, a DMA request signal is always de-asserted for at least two clock cycles before it is asserted again. This property is applicable to each DMA request signal independently; therefore, the AES block can have multiple DMA request signals active in parallel, assuming the operation supports it.