Hard Processor System Technical Reference Manual: Agilex™ 5 SoCs

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

12.1.4. HPS Mailbox System Integration

The following figure shows the HPS mailbox block diagram.

Figure 291. HPS Mailbox Block Diagram

The HPS mailbox consists of the following:

  • Mailbox Memory: 256 bytes of memory, accessible as 64 x 32 bit words. The data is organized as follows:
    • 16 x 32 bit words store control registers to help manage communication between HPS and SDM
    • 32 x 32 bit words implement a circular buffer for commands
    • 16 x 32 bit words implement a circular buffer for responses
  • SDM 2 HPS Doorbell: Register allows SDM to issue an interrupt to HPS letting it know data is available. HPS accesses this register to clear the interrupt.
  • HPS 2 SDM Doorbell: Register allows HPS to issue an interrupt to SDM letting it know data is available.
  • Streaming Interface: Allows data to be streamed from HPS to SDM.