Arria V Hard Processor System Technical Reference Manual

ID 683011
Date 12/02/2022
Public
Document Table of Contents

28.6.1. MPU Standby and Event Interfaces

MPU standby signals are notification signals to the FPGA fabric that the MPU is in standby. Event signals are used to wake up the Cortex®-A9 processors from a wait for event (WFE) state. The following shows the signals in the interface:

  • h2f_mpu_events—MPU standby and event interface, including the following signals.
  • h2f_mpu_eventi—Sends an event from logic in the FPGA fabric to the MPU. This FPGA‑to‑HPS signal is used to wake up a processor that is in a Wait For Event state. Asserting this signal has the same effect as executing the SEV instruction in the Cortex®-A9. This signal must be de‑asserted until the FPGA fabric is powered‑up and configured.
  • h2f_mpu_evento—Sends an event from the MPU to logic in the FPGA fabric. This HPS‑to‑FPGA signal is asserted when an SEV instruction is executed by one of the Cortex®-A9processors.
  • h2f_mpu_standbywfe[1:0]—Indicates which Cortex®-A9 processor is in the WFE state
  • h2f_mpu_standbywfi[1:0]—Indicates which Cortex-A9 processor is in the wait for interrupt (WFI) state

The MPU provides signals to indicate when it is in a standby state. These signals are available to custom hardware designs in the FPGA fabric.