Hard Processor System Technical Reference Manual: Agilex™ 5 SoCs

ID 814346
Date 4/01/2024
Public
Document Table of Contents

13.4.2.4.3. F2SDRAM AxUSER Firewall

The F2SDRAM AxUSER firewall verifies that every Fabric transaction sets AxUSER[7:0] to 0xE0 so that soft logic is not able to spoof the master ID of any other requestor like a core, TSN, DMA, and so on, in an attempt to work around the masterID firewall or other security features.

By convention, accesses from F2SDRAM:

  • AxUSER[7:0] must be set to 0xE0
  • AxUSER[8] = 1, then AxPROT settings are used to determine security
  • AxUSER[8] = 0, then AxPROT settings are over-written, and transactions are non-secure