The four major components of the QoS are listed.
•AXI QoS-400 Regulators on AXI Interconnect.
•AXI and APB Timeout Units (ATB).
•AXI QoS Virtual Network Channels (QVN network).
•DDR QoS Controller in DDR memory controller.
Each one of these components implements different pieces of QoS support, but together the individual pieces form the complete QoS System solution. Of the four components, the DDR controller has the most sophisticated QoS features, but the other three components are essential to guarantee the overall required system performance.