Hard Processor System Technical Reference Manual: Agilex™ 5 SoCs

ID 814346
Date 7/19/2024
Public
Document Table of Contents

4.1.5.1.2. Non-coherent Agent Interface Unit (NCAIU)

NCAIU0 is configured for ACE-lite to support I/O coherence from the fabric via the F2H bridge. NCAIU1 is configured for ACE-lite to support I/O coherence from the GIC. NCIU2 is configured for ACE-lite to support I/O coherence from PSS NoC. NCAIU2 is configured for ACE-lite + DVM to support I/O coherence and DVM messages from the SMMU.

For each NCAIU, the following credit counters are implemented:

  • CMD message credit counter per instance of DCE
  • CMD message credit counter per instance of DMI
  • CMD message credit counter per instance of DII

For each NCAIU, the following resources are implemented based on message credits:

  • Snoop transaction table: This transaction table is sized based on SNP message credits

The following resources are implemented per NCAIU:

  • Outstanding transaction table control entries which limit the number of outstanding transactions an NCAIU can have at a given time.