Scalable Scatter-Gather DMA Intel® FPGA IP User Guide

ID 823097
Date 4/07/2025
Public
Document Table of Contents

3.11.4. Soft Reset Handshake Flow

The following sequence describes the SSGDMA IP soft reset handshake flow:
  1. Software writes to reset_prefetch_engine bit in CTRL register to trigger soft reset for Prefetcher Engine.
  2. SSGDMA IP de-asserts run_prefetch_engine bit and clear reset_prefetch_engine bit in CTRL register upon completing soft reset sequence.
  3. Software polls for de-assertion of reset_prefetch_engine bit of CTRL register.
  4. Software writes to q_pause_agent_control bit of Q_CTRL register of the device port.
  5. SSGDMA IP de-asserts the q_en bit in the Q_CTRL register of the corresponding device port and updates the q_agent_control_paused bit in the Q_STATUS register of the device port upon completion of the pause sequence for that device port.
  6. Software polls for q_agent_control_paused bit assertion of Q_STATUS register of the device port.
  7. Software writes to q_sw_reset_req bit of Q_CTRL register of the device port.
  8. SSGDMA IP resets all Device Port control registers to default values. The q_resetting bit of the device port's Q_STATUS register is asserted until the soft reset sequence of the device port is completed.
  9. Software polls for q_resetting bit de-assertion of Q_STATUS register of the device port.
  10. Software repeats steps 4 to 9 for all device ports.
  11. Software re-initializes Device Port control registers for each device port as described in General DMA Operation Flow.