R-Tile Avalon® Streaming FPGA IP for PCI Express* User Guide

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ID 683501
Date 8/11/2025
Public
Document Table of Contents
Document Table of Contents x
1. About the R-Tile Avalon® Streaming Intel® FPGA IP for PCI Express 2. IP Architecture and Functional Description 3. Advanced Features 4. Interfaces 5. Parameters 6. Troubleshooting/Debugging 7. R-Tile Avalon® Streaming FPGA IP for PCI Express* User Guide Archives 8. Document Revision History for the R-Tile Avalon® Streaming FPGA IP for PCI Express* User Guide A. Configuration Space Registers B. Root Port Enumeration C. Implementation of Address Translation Services (ATS) in Endpoint Mode D. Packets Forwarded to the User Application in TL Bypass Mode E. Margin Masks for the R-Tile Avalon Streaming FPGA IP for PCI Express F. Using the Avery BFM for R-Tile PCI Express Gen5 Simulations
1. About the R-Tile Avalon® Streaming Intel® FPGA IP for PCI Express x
1.1. Glossary 1.2. Overview 1.3. Features 1.4. Release Information 1.5. Device Family Support 1.6. Performance and Resource Utilization 1.7. IP Core Support Levels
1.2. Overview x
1.2.1. Standards and Specifications Compliance
1.3. Features x
1.3.1. Multifunction and Virtualization Features
2. IP Architecture and Functional Description x
2.1. Overview 2.2. PCIe Hard IP Mode 2.3. PIPE Direct Mode
2.2. PCIe Hard IP Mode x
2.2.1. Clocking 2.2.2. Reset 2.2.3. PCI Express Protocol Stack
2.2.2. Reset x
2.2.2.1. Single PERST 2.2.2.2. Independent PERST Pins 2.2.2.3. Independent GPIO PERST
2.2.2.2. Independent PERST Pins x
2.2.2.2.1. REFCLK and PERST Guidelines When Using Independent PERST Pins
2.2.2.3. Independent GPIO PERST x
2.2.2.3.1. REFCLK and PERST Guidelines when Using Independent GPIO PERST
2.2.3. PCI Express Protocol Stack x
2.2.3.1. PMA 2.2.3.2. Data Link Layer Overview 2.2.3.3. Transaction Layer Overview
2.2.3.3. Transaction Layer Overview x
2.2.3.3.1. Deferrable Memory Write (DMWr)
2.3. PIPE Direct Mode x
2.3.1. Clocking 2.3.2. Reset 2.3.3. PIPE Layer
2.3.3. PIPE Layer x
2.3.3.1. Preset Mappings
3. Advanced Features x
3.1. PCIe Port Bifurcation and PHY Channel Mapping 3.2. Virtualization Support 3.3. TL Bypass Mode
3.2. Virtualization Support x
3.2.1. SR-IOV Support 3.2.2. VirtIO Support
3.2.1. SR-IOV Support x
3.2.1.1. SR-IOV Supported Features List 3.2.1.2. Implementation 3.2.1.3. VF to PF Mapping 3.2.1.4. Function Level Reset (FLR)
3.2.1.2. Implementation x
3.2.1.2.1. VF Error Flag Interface (for x16/x8 Cores Only)
3.2.2. VirtIO Support x
3.2.2.1. VirtIO Supported Features List 3.2.2.2. Overview 3.2.2.3. Parameters 3.2.2.4. VirtIO PCI Configuration Access Interface 3.2.2.5. Registers
3.2.2.5. Registers x
3.2.2.5.1. VirtIO Common Configuration Capability Register (Address: 0x012) 3.2.2.5.2. VirtIO Common Configuration BAR Indicator Register (Address: 0x013) 3.2.2.5.3. VirtIO Common Configuration BAR Offset Register (Address: 0x014) 3.2.2.5.4. VirtIO Common Configuration Structure Length Register (Address 0x015) 3.2.2.5.5. VirtIO Notifications Capability Register (Address: 0x016) 3.2.2.5.6. VirtIO Notifications BAR Indicator Register (Address: 0x017) 3.2.2.5.7. VirtIO Notifications BAR Offset Register (Address: 0x018) 3.2.2.5.8. VirtIO Notifications Structure Length Register (Address: 0x019) 3.2.2.5.9. VirtIO Notifications Notify Off Multiplier Register (Address: 0x01A) 3.2.2.5.10. VirtIO ISR Status Capability Register (Address: 0x02F) 3.2.2.5.11. VirtIO ISR Status BAR Indicator Register (Address: 0x030) 3.2.2.5.12. VirtIO ISR Status BAR Offset Register (Address: 0x031) 3.2.2.5.13. VirtIO ISR Status Structure Length Register (Address: 0x032) 3.2.2.5.14. VirtIO Device Specific Capability Register (Address: 0x033) 3.2.2.5.15. VirtIO Device Specific BAR Indicator Register (Address: 0x034) 3.2.2.5.16. VirtIO Device Specific BAR Offset Register (Address 0x035) 3.2.2.5.17. VirtIO Device Specific Structure Length Register (Address: 0x036) 3.2.2.5.18. VirtIO PCI Configuration Access Capability Register (Address: 0x037) 3.2.2.5.19. VirtIO PCI Configuration Access BAR Indicator Register (Address: 0x038) 3.2.2.5.20. VirtIO PCI Configuration Access BAR Offset Register (Address: 0x039) 3.2.2.5.21. VirtIO PCI Configuration Access Structure Length Register (Address: 0x03A) 3.2.2.5.22. VirtIO PCI Configuration Access Data Register (Address: 0x03B)
3.3. TL Bypass Mode x
3.3.1. Overview 3.3.2. Register Settings for the TL Bypass Mode 3.3.3. Hard IP Reconfiguration Interface 3.3.4. Avalon® Streaming Interface
3.3.2. Register Settings for the TL Bypass Mode x
3.3.2.1. TLPBYPASS_ERR_EN (Address 0x1314) 3.3.2.2. TLPBYPASS_ERR_STATUS (Address 0x1310)
3.3.4. Avalon® Streaming Interface x
3.3.4.1. Configuration TLP 3.3.4.2. Transmit Interface 3.3.4.3. Receive Interface 3.3.4.4. Malformed TLP 3.3.4.5. ECRC
4. Interfaces x
4.1. Clocks and Resets 4.2. Serial Data Interface 4.3. PCI Express Mode 4.4. PIPE Direct Mode
4.1. Clocks and Resets x
4.1.1. Clocks 4.1.2. Resets
4.3. PCI Express Mode x
4.3.1. Avalon® Streaming Interface 4.3.2. Precision Time Measurement (PTM) Interface (Endpoint Only) 4.3.3. Hot Plug Interface 4.3.4. Interrupt Interface 4.3.5. Hard IP Reconfiguration Interface 4.3.6. Error Interface 4.3.7. Completion Timeout Interface 4.3.8. Configuration Intercept Interface 4.3.9. Power Management Interface 4.3.10. Hard IP Status Interface 4.3.11. Page Request Services (PRS) Interface (Endpoint Only) 4.3.12. Function-Level Reset (FLR) Interface (Endpoint Only) 4.3.13. SR-IOV VF Error Flag Interface (Endpoint Only) 4.3.14. General Purpose VSEC Interface
4.3.1. Avalon® Streaming Interface x
4.3.1.1. TLP Header and Data Alignment for the Avalon® streaming RX and TX Interfaces 4.3.1.2. Credit Control 4.3.1.3. Avalon® Streaming RX Interface 4.3.1.4. Avalon® Streaming TX Interface 4.3.1.5. Tag Allocation
4.3.1.2. Credit Control x
4.3.1.2.1. Credit Interface - Data and Header 4.3.1.2.2. Credit Initialization 4.3.1.2.3. Credit Update/Release 4.3.1.2.4. RX Flow Control Interface 4.3.1.2.5. TX Flow Control Interface
4.3.1.3. Avalon® Streaming RX Interface x
4.3.1.3.1. Application Logic Guidelines for the Avalon Streaming RX Interface
4.3.1.4. Avalon® Streaming TX Interface x
4.3.1.4.1. Application Logic Guidelines for the Avalon Streaming TX Interface 4.3.1.4.2. Avalon® Streaming TX Interface pX_tx_st_ready_o Behavior
4.3.1.5. Tag Allocation x
4.3.1.5.1. Completion Buffer Size
4.3.4. Interrupt Interface x
4.3.4.1. Legacy Interrupts 4.3.4.2. MSI 4.3.4.3. MSI-X
4.3.4.3. MSI-X x
4.3.4.3.1. Implementing MSI-X Interrupts
4.3.9. Power Management Interface x
4.3.9.1. D3Hot Entry 4.3.9.2. D3Hot Exit 4.3.9.3. D3Cold Entry 4.3.9.4. D3Cold Exit
4.3.9.2. D3Hot Exit x
4.3.9.2.1. D3Hot Exit Initiated by Host 4.3.9.2.2. D3Hot Exit Initiated by EP
4.4. PIPE Direct Mode x
4.4.1. Data Signals 4.4.2. Command and Status Signals 4.4.3. Message Bus Signals 4.4.4. Deskew Signals 4.4.5. PIPE Direct Reset Sequence 4.4.6. PIPE Direct Speed Change 4.4.7. PIPE Lane Reset Staggering 4.4.8. Unused Lanes in PIPE Direct Mode
4.4.1. Data Signals x
4.4.1.1. Transmit Signals 4.4.1.2. Receive Signals
4.4.4. Deskew Signals x
4.4.4.1. MAC to PHY (M2P) Signals 4.4.4.2. PHY to MAC (P2M) Signals
5. Parameters x
5.1. Top-Level Settings 5.2. Core Parameters 5.3. Design Examples
5.2. Core Parameters x
5.2.1. Avalon Parameters 5.2.2. Base Address Registers 5.2.3. PCI Express and PCI Capabilities Parameters
5.2.3. PCI Express and PCI Capabilities Parameters x
5.2.3.1. Device Capabilities 5.2.3.2. VirtIO Parameters 5.2.3.3. Link Capabilities 5.2.3.4. Legacy Interrupt Pin Register 5.2.3.5. MSI Capabilities 5.2.3.6. MSI-X Capabilities 5.2.3.7. Slot Capabilities 5.2.3.8. Latency Tolerance Reporting (LTR) 5.2.3.9. Process Address Space ID (PASID) 5.2.3.10. Device Serial Number Capability 5.2.3.11. Page Request Service (PRS) 5.2.3.12. Access Control Service (ACS) 5.2.3.13. Power Management 5.2.3.14. Vendor Specific Extended Capability (VSEC) Registers 5.2.3.15. TLP Processing Hints (TPH) 5.2.3.16. Address Translation Services (ATS) Capabilities 5.2.3.17. Precision Time Measurement (PTM)
5.3. Design Examples x
5.3.1. Design Example Files 5.3.2. Generated HDL Format 5.3.3. Target Development Kit 5.3.4. Currently Selected Design Example
6. Troubleshooting/Debugging x
6.1. Hardware Debug 6.2. Operating System Tools and Utilities 6.3. Signal Tap Logic Analyzer 6.4. Using the Hard IP Reconfiguration Interface for Debugging 6.5. Other Interfaces That Can Be Used for Debug Activities 6.6. Debug Toolkit
6.1. Hardware Debug x
6.1.1. Debugging Link Training Issues 6.1.2. Debugging Device Enumeration Issues 6.1.3. Debugging Data Transfer and Performance Issues
6.1.3. Debugging Data Transfer and Performance Issues x
6.1.3.1. Advanced Error Reporting (AER)
6.2. Operating System Tools and Utilities x
6.2.1. Using lspci Utility to Read Negotiated Link Speed
6.4. Using the Hard IP Reconfiguration Interface for Debugging x
6.4.1. Using the Hard IP Reconfiguration Interface to Enable and Read ECRC and LCRC Error Counts
6.6. Debug Toolkit x
6.6.1. Overview 6.6.2. Enabling the R-Tile Debug Toolkit 6.6.3. Launching the R-Tile Debug Toolkit 6.6.4. Using the R-Tile Debug Toolkit
6.6.4. Using the R-Tile Debug Toolkit x
6.6.4.1. R-Tile Information 6.6.4.2. Event Counters 6.6.4.3. Link Inspector 6.6.4.4. Configuration Space 6.6.4.5. Channel Parameters
6.6.4.5. Channel Parameters x
6.6.4.5.1. General PHY 6.6.4.5.2. Tx Path 6.6.4.5.3. Rx Path 6.6.4.5.4. Lane Margining
C. Implementation of Address Translation Services (ATS) in Endpoint Mode x
C.1. Sending Translated/Untranslated Requests C.2. Sending a Page Request Message from the Endpoint (EP) to the Root Complex (RC) C.3. Invalidating Requests/Completions
D. Packets Forwarded to the User Application in TL Bypass Mode x
D.1. Upstream TL Bypass Mode D.2. Downstream TL Bypass Mode
E. Margin Masks for the R-Tile Avalon Streaming FPGA IP for PCI Express x
E.1. Margin Masks Overview E.2. 5x5 Testing Efficiency E.3. Debug Toolkit Margin Methodology
E.2. 5x5 Testing Efficiency x
E.2.1. First Time Testing E.2.2. Spot Check Testing
E.3. Debug Toolkit Margin Methodology x
E.3.1. Debug Toolkit Testing Process
F. Using the Avery BFM for R-Tile PCI Express Gen5 Simulations x
F.1. Overview F.2. Generate the R-Tile PCIe PIO Design Example F.3. Integrate the Avery BFM Testbench Components F.4. Configure Avery BFM and Set Up Simulation Scripts F.5. Compile and Simulate
F.3. Integrate the Avery BFM Testbench Components x
F.3.1. Testbench Integration
F.4. Configure Avery BFM and Set Up Simulation Scripts x
F.4.1. Avery BFM Configuration F.4.2. Simulation Scripts Set-up
F.5. Compile and Simulate x
F.5.1. Run Simulation Script F.5.2. Simulation Results
1. About the R-Tile Avalon® Streaming Intel® FPGA IP for PCI Express
2. IP Architecture and Functional Description
3. Advanced Features
4. Interfaces
5. Parameters
6. Troubleshooting/Debugging
7. R-Tile Avalon® Streaming FPGA IP for PCI Express* User Guide Archives
8. Document Revision History for the R-Tile Avalon® Streaming FPGA IP for PCI Express* User Guide
A. Configuration Space Registers
B. Root Port Enumeration
C. Implementation of Address Translation Services (ATS) in Endpoint Mode
D. Packets Forwarded to the User Application in TL Bypass Mode
E. Margin Masks for the R-Tile Avalon Streaming FPGA IP for PCI Express
F. Using the Avery BFM for R-Tile PCI Express Gen5 Simulations

2.2.3.3. Transaction Layer Overview

The following figure shows the major blocks in the R-Tile Avalon® -ST IP for PCI Express Transaction Layer:

Figure 13. R-Tile Avalon® -ST IP for PCI Express Transaction Layer Block Diagram

The RAS (Reliability, Availability, and Serviceability) block includes a set of features to maintain the integrity of the link.

For example: Transaction Layer inserts an optional ECRC in the transmit logic and checks it in the receive logic to provide End-to-End data protection.

When the application logic sets the TLP Digest (TD) bit in the Header of the TLP, the R-Tile Avalon® -ST IP for PCIe will append the ECRC automatically.

Note: In TL Bypass mode, the PCIe Hard IP does not generate/check the ECRC and will not remove it if the received TLP has the ECRC.

The TX block sends out the TLPs that it receives as-is. It also sends the information about non-posted TLPs to the CPL Timeout Block for CPL timeout detection.

The R-Tile Avalon® -ST IP for PCI Express RX block consists of two main blocks:
  • Filtering block: This module checks if the TLP is good or bad and generates the associated error message and completion. It also tracks received completions and updates the completion timeout (CPL timeout) block.
  • RX Buffer Queue: The R-Tile IP for PCIe has separate queues for posted/non-posted transactions and completions. This avoids head-of-queue blocking on the received TLPs and provides flexibility to extract TLPs according to the PCIe ordering rules.
Figure 14. R-Tile Avalon® -ST IP for PCI Express RX Block Overview
Note: (*) The Received CPL Processing block includes the CPL tracking mechanism.
Note: The Avalon-ST interface uses a split-bus architecture. In the x16 and x8 configurations, the 1024-bit Avalon-ST data bus consists of four segments of 256-bit data. This is done to improve the bandwidth efficiency of this interface. With this split-bus architecture, multiple TLP packets can be transmitted or received in a single clock cycle. For more details, refer to Avalon Streaming Interface.

Section Content
Deferrable Memory Write (DMWr)

Level Two Title