Scalable Scatter-Gather DMA Intel® FPGA IP User Guide

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ID 823097
Date 4/07/2025
Public
Document Table of Contents
Document Table of Contents x
1. Terms and Acronyms 2. Introduction 3. Functional Description 4. Interfaces 5. HAL Driver for DMA SoC Mode  6. Parameters 7. Registers 8. Document Revision History for the Scalable Scatter-Gather DMA Intel® FPGA IP User Guide
2. Introduction x
2.1. Device Family Support 2.2. Release Information 2.3. Resource Utilization
3. Functional Description x
3.1. DMA PCIe* Mode 3.2. DMA SoC Mode 3.3. Device Port 3.4. Prefetcher Engine 3.5. DMA Arbiter 3.6. DMA Router 3.7. CSRUnit 3.8. Descriptor Handling 3.9. Interrupts 3.10. Reset Initialization Flows 3.11. Transaction Flow
3.1. DMA PCIe* Mode x
3.1.1. Submodules
3.1.1. Submodules x
3.1.1.1. PCIe* TLP Constructor 3.1.1.2. PCIe* TLP ID Generation 3.1.1.3. PCIe TX Credit Controller 3.1.1.4. PCIe* TX Scheduler 3.1.1.5. PCIe TLP Completer 3.1.1.6. PCIe RX Router 3.1.1.7. PCIe* MSI-X Controller 3.1.1.8. PCIe BAR0 3.1.1.9. PCIe Bursting Manager (BAM) 3.1.1.10. Completion Timeout Parser 3.1.1.11. Control Shadow Parser
3.2. DMA SoC Mode x
3.2.1. Interrupt Controller 3.2.2. Host AXI-4 Agent 3.2.3. Host CSR AXI-4 Lite Agent
3.3. Device Port x
3.3.1. ST Source Agent/ST Sink Agent/MM Agent 3.3.2. Descriptor Engine 3.3.3. Agent Controller 3.3.4. Constructor 3.3.5. Responder 3.3.6. Width Adaptation FIFO
3.8. Descriptor Handling x
3.8.1. Link Descriptor 3.8.2. Data Descriptor 3.8.3. Responder Descriptor 3.8.4. Descriptor Chain 3.8.5. Aligned and Unaligned Transfer Support
3.8.2. Data Descriptor x
3.8.2.1. Data Descriptor - H2D Streaming Transfer 3.8.2.2. Data Descriptor - D2H Streaming Transfer 3.8.2.3. Data Descriptor - H2D Memory Transfer
3.8.3. Responder Descriptor x
3.8.3.1. Responder Descriptor - H2D Streaming Transfer 3.8.3.2. Responder Descriptor - D2H Streaming Transfer 3.8.3.3. Responder Descriptor - H2D Memory Transfer
3.8.4. Descriptor Chain x
3.8.4.1. Descriptor Fetch and Status Update Mechanism
3.11. Transaction Flow x
3.11.1. General DMA Operation Flow 3.11.2. Host to Device (H2D) Flow 3.11.3. Device to Host (D2H) Flow 3.11.4. Soft Reset Handshake Flow
4. Interfaces x
4.1. Port List 4.2. DMA PCIe* Mode Interfaces 4.3. DMA SoC Mode Interfaces 4.4. Device Port Interfaces 4.5. Resets 4.6. Clocks
4.2. DMA PCIe* Mode Interfaces x
4.2.1. Application Packet Receive Interface 4.2.2. Application Packet Transmit Interface 4.2.3. Control Shadow Interface 4.2.4. Transmit Flow Control Credit Interface 4.2.5. Completion Timeout Interface 4.2.6. PCIe* Miscellaneous Signals 4.2.7. Control and Status Register Responder Manager Interface 4.2.8. Bursting Manager Interface
4.3. DMA SoC Mode Interfaces x
4.3.1. Host AXI-4 Memory Map Manager Interface 4.3.2. Host AXI-4 Lite CSR Memory Map Subordinate Interface 4.3.3. Interrupt Interface
4.4. Device Port Interfaces x
4.4.1. Device to Host <PORT#> AXI-ST Subordinate Interface 4.4.2. Device to Host <PORT#> Avalon-ST Sink Interface 4.4.3. Host to Device <PORT#> AXI-ST Manager Interface 4.4.4. Host to Device <PORT#> Avalon-ST Source Interface 4.4.5. Host to Device <PORT#> AXI-4 Manager Interface
5. HAL Driver for DMA SoC Mode  x
5.1. Descriptor Indexing  5.2. HAL Public API 
5.1. Descriptor Indexing  x
5.1.1. Data Descriptors  5.1.2. Responders 
5.2. HAL Public API  x
5.2.1. Software Features 5.2.2. intel_ssgdma.c  5.2.3. intel_ssgdma_global.c 5.2.4. intel_ssgdma_device_port.c  5.2.5. intel_ssgdma_descriptor.c 
6. Parameters x
6.1. DMA Settings 6.2. Device Port Settings 6.3. DMA PCIe Mode Settings 6.4. DMA SoC Mode Settings 6.5. Example Design
6.2. Device Port Settings x
6.2.1. H2D MM 6.2.2. H2D ST 6.2.3. D2H ST
7. Registers x
7.1. Global CSR 7.2. MSI-X Memory Space 7.3. Device Port Control Register
1. Terms and Acronyms
2. Introduction
3. Functional Description
4. Interfaces
5. HAL Driver for DMA SoC Mode 
6. Parameters
7. Registers
8. Document Revision History for the Scalable Scatter-Gather DMA Intel® FPGA IP User Guide

3.1. DMA PCIe* Mode

You must pair the SSGDMA IP of DMA PCIe* mode with PCIe* IP. For Agilex™ 5 devices, you need to connect SSGDMA IP to the GTS AXI Streaming Intel® FPGA IP for PCI Express.

Table 4.  Supported PCI Express* IP for SSGDMA IP
Device Family Supported Intel® FPGA IP for PCI Express*
Agilex™ 5 GTS AXI Streaming Intel® FPGA IP for PCI Express
The DMA PCIe* mode supports the following functionalities:
  • Single physical function (PF0)
  • GTS AXI Streaming Intel® FPGA IP for PCI Express in Endpoint mode with 128, 256-bit data width, 300 MHz AXI-ST interface clock frequency
  • TLP processing and generation
  • PCIe* interrupt generation (MSI-X)
  • Credit control
  • Up to 512 bytes MPS (based on the GTS AXI Streaming Intel® FPGA IP for PCI Express)
  • Up to 4096 bytes MRRS (based on the GTS AXI Streaming Intel® FPGA IP for PCI Express)
  • Up to 256 Request Tags (based on the GTS AXI Streaming Intel® FPGA IP for PCI Express)

The SSGDMA IP supports a 300 MHz AXI-ST interface operating clock frequency. You need to make sure that the AXI-Stream clock of the GTS AXI Streaming Intel® FPGA IP for PCI Express also runs at 300 MHz. Additionally, enable the PCIe IP's Completion Timeout and Control Shadow interfaces and connect them to the SSGDMA IP as required. Note that the SSGDMA IP does not support virtual functions.

For Agilex™ 5 devices, there are 2 DMA IPs available for PCIe with DMA implementation:
  • Scalable Scatter-Gather DMA Intel® FPGA IP
  • GTS AXI Multichannel DMA IP for PCI Express.
The following feature comparison table highlights key differences between the two IPs.
Table 5.  Feature Comparison between Scalable Scatter-Gather DMA Intel® FPGA IP and GTS AXI Multichannel DMA IP for PCI Express
Feature Scalable Scatter-Gather DMA IP (DMA PCIe Mode) GTS AXI Multichannel DMA IP for PCI Express
PCIe streaming interface data width 128-bit, 256-bit 128-bit, 256-bit
PCIe Port Type Endpoint Endpoint, Root Port
Multiple physical functions support No Yes
SR-IOV/ virtual functions support No Yes
Number of DMA Channels Up to 8 channels Up to 256 channels
Number of DMA user port Up to 8 ports, with 1 DMA channel per port Single port, up to 256 virtual channels.
DMA user port
  • · AVST, AXI-ST, AXI4
  • · Independently configurable type/width/frequency
  • AXI-ST, AXI4
  • Interface width and frequency determined by PCIe configuration
Bursting Master (BAM) support Yes Yes
Bursting Slave (BAS) support No Yes
Completion Status Update
  • MSI-X interrupt
  • Writeback
  • MSI-X interrupt
  • Writeback
Video flushing mechanism support Yes No

Section Content
Submodules

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