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The HN-F protocol queue (POCQ) is a key shared system resource that communicates with the memory controller for external memory access.
All requests for normal memory must go through the HN-F to ensure proper ordering (PoS) and functional correctness for coherence (PoC).
The HN-F provides QoS capabilities in support of the following traffic classes:
The CCN-502 uses QoS values to designate these traffic classes. Every request to the HN-F has a 4-bit QoS value that is associated with it, with a higher number indicating a higher priority. The four QoS classes are: