Hard Processor System Component Reference Manual: Agilex™ 5 SoCs

ID 813752
Date 8/09/2024
Public
Document Table of Contents

4.1. HPS System Reset Considerations

After any one of the four Watchdog timers expires and generates a system reset request to the SDM, the SDM then performs one of three types of system resets that can be chosen from within the Quartus® Prime Pro Edition tool:
  • HPS Cold reset
  • HPS Warm reset
  • Trigger Remote Update
In the Platform Designer under HPS IP, you must:
  1. Select the HPS Clocks, Resets, Power tab.
  2. Select the Power & Resets tab.
  3. Click on the Enable watchdog reset check box.
  4. Choose one of three choices from the pull-down menu for the Watchdog SDM Configuration label:
    • HPS Cold reset
      • Impact on HPS—The SDM holds the processor in reset. The SDM loads the FSBL from the same bitstream that was loaded into the device prior to the cold reset into the HPS on-chip memory. When successfully completed, the SDM releases the HPS reset causing the processor to start executing code from the reset exception address.
      • Impact on Fabric—The FPGA fabric is untouched during the reset. After exiting reset, software determines whether to reconfigure the fabric portion.
    • HPS Warm reset
      • Impact on HPS—The SDM holds the processor in reset. The FSBL remains in the on-chip RAM during a warm reset. The SDM takes the processor out of reset, and the processor runs the FSBL in on-chip RAM.
      • Impact on Fabric—The fabric portion is left alone during the reset. After exiting reset, software determines whether to reconfigure the fabric portion.
    • Trigger Remote Update
      • Impact on HPS—The SDM holds the processor in reset. The SDM loads the FSBL from the next valid *.pof image or factory image into the HPS on-chip memory. The *.pof contains the data to configure the fabric portion of the HPS and the FSBL payload. When successfully completed, the SDM releases the HPS from reset and the processor begins executing code from the reset exception address.
      • Impact on Fabric—The fabric portion is first erased, then reconfigured with the next valid Core RBF or Factory Core RBF. There must always be a valid factory RBF present.