1.5 CCI operation
The CCI-550 has dual-layer request channels, meaning that it can handle two requests per cycle. It also has a central Transaction Tracker (TT) that handles coherency and ordering. The TT is non-blocking and can reorder requests according to QoS requirements.
following figure shows the CCI-550 high-level operation.
Figure 1-2 CCI-550 high-level operation
The TT uses a snoop filter to determine where to send snoop requests. To
- The snoop filter has four partitions.
- The read data and write data interconnects are fully-connected
Write responses also use a crossbar interconnect and the reorder buffer helps
the CCI-550 to meet
ordering requirements without stalling requests.
Each interface has a configurable number of register stages, with a minimum of
one stage for each interface.