GTS AXI Streaming IP for PCI Express* Design Example User Guide

Download PDF
ID 817713
Date 10/23/2025
Public
Document Table of Contents
Document Table of Contents x
1. About the GTS AXI Streaming IP for PCI Express* Design Example 2. Quick Start Guide 3. Document Revision History for the GTS AXI Streaming IP for PCI Express* Design Example User Guide A. Appendix
1. About the GTS AXI Streaming IP for PCI Express* Design Example x
1.1. Programmed Input/Output Design Example 1.2. Programmed Input/Output Design Example Functional Description 1.3. Single-Root I/O Virtualization (SR-IOV) Design Example 1.4. Performance Design Example
1.2. Programmed Input/Output Design Example Functional Description x
1.2.1. GTS AXI Streaming IP—Design Under Test (DUT) 1.2.2. PIO Application 1.2.3. On-Chip Memory (MEM) 1.2.4. GTS System PLL Clocks IP 1.2.5. GTS Reset Sequencer IP 1.2.6. Reset Release IP
1.2.2. PIO Application x
1.2.2.1. Scheduler 1.2.2.2. Read Write Module 1.2.2.3. Avalon® Memory-Mapped Interface 1.2.2.4. Completion Module 1.2.2.5. Width Adapter 1.2.2.6. Transmit Flow Control 1.2.2.7. AXI-S to Avalon® -ST Adapter 1.2.2.8. Soft Reset Controller
1.3. Single-Root I/O Virtualization (SR-IOV) Design Example x
1.3.1. Single-Root I/O Virtualization (SR-IOV) Design Example Functional Description
1.4. Performance Design Example x
1.4.1. Performance Design Example Functional Description
2. Quick Start Guide x
2.1. Directory Structure 2.2. Generating the Design Example 2.3. Simulating the Design Example 2.4. Design Example Simulation Testbench 2.5. Compiling the Design Example 2.6. Hardware and Software Requirements 2.7. Program the FPGA 2.8. Installing the Linux Kernel Driver 2.9. Running the Design Example
2.3. Simulating the Design Example x
2.3.1. Steps to Run Simulation using VCS* MX 2.3.2. Steps to Run Simulation using QuestaSIM* 2.3.3. Steps to Run Simulation using Xcelium* 2.3.4. Steps to Run Simulation using Riviera-PRO*
2.3.1. Steps to Run Simulation using VCS* MX x
2.3.1.1. Running VCS* MX Simulation in Interactive Mode
2.4. Design Example Simulation Testbench x
2.4.1. Test Driver Module 2.4.2. Root Port BFM 2.4.3. PIO Design Example Testbench 2.4.4. Single Root I/O Virtualization (SR-IOV) Design Example Testbench 2.4.5. Performance Design Example Testbench
2.4.2. Root Port BFM x
2.4.2.1. BFM Memory Map 2.4.2.2. Configuration Space Bus and Device Numbering 2.4.2.3. Configuration of Root Port and Endpoint 2.4.2.4. Issuing Read and Write Transactions to the Application Layer
2.9. Running the Design Example x
2.9.1. Running the PIO Design Example 2.9.2. Running the Single Root I/O Virtualization (SR-IOV) Design Example
A. Appendix x
A.1. BFM Procedures and Functions
A.1. BFM Procedures and Functions x
A.1.1. ebfm_barwr Procedure A.1.2. ebfm_barwr_imm Procedure A.1.3. ebfm_barrd_wait Procedure A.1.4. ebfm_barrd_nowt Procedure A.1.5. ebfm_cfgwr_imm_wait Procedure A.1.6. ebfm_cfgwr_imm_nowt Procedure A.1.7. ebfm_cfgrd_wait Procedure A.1.8. ebfm_cfgrd_nowt Procedure A.1.9. BFM Configuration Procedures A.1.10. BFM Shared Memory Access Procedures A.1.11. BFM Log and Message Procedures A.1.12. Verilog HDL Formatting Functions
A.1.9. BFM Configuration Procedures x
A.1.9.1. ebfm_cfg_rp_ep Procedure A.1.9.2. ebfm_cfg_decode_bar Procedure
A.1.10. BFM Shared Memory Access Procedures x
A.1.10.1. Shared Memory Constants A.1.10.2. shmem_write Task A.1.10.3. shmem_read Function A.1.10.4. shmem_display Verilog HDL Function A.1.10.5. shmem_fill Procedure A.1.10.6. shmem_chk_ok Function
A.1.11. BFM Log and Message Procedures x
A.1.11.1. ebfm_display Verilog HDL Function A.1.11.2. ebfm_log_stop_sim Verilog HDL Function A.1.11.3. ebfm_log_set_suppressed_msg_mask Task A.1.11.4. ebfm_log_set_stop_on_msg_mask Verilog HDL Task A.1.11.5. ebfm_log_open Verilog HDL Function A.1.11.6. ebfm_log_close Verilog HDL Function
A.1.12. Verilog HDL Formatting Functions x
A.1.12.1. himage1 A.1.12.2. himage2 A.1.12.3. himage4 A.1.12.4. himage8 A.1.12.5. himage16 A.1.12.6. dimage1 A.1.12.7. dimage2 A.1.12.8. dimage3 A.1.12.9. dimage4 A.1.12.10. dimage5 A.1.12.11. dimage6 A.1.12.12. dimage7
1. About the GTS AXI Streaming IP for PCI Express* Design Example
2. Quick Start Guide
3. Document Revision History for the GTS AXI Streaming IP for PCI Express* Design Example User Guide
A. Appendix

1.2.2.6. Transmit Flow Control

The PIO application transmits packets only when the link partner's receive buffer has sufficient capacity to accept the TLP. This buffer availability is communicated via the Transmit Flow Control Credit Interface of the DUT to the Transmit Flow Control module of the PIO block.

Transmit credits are initialized for each TLP category based on the initial credit values received from the link partner. When the link partner acknowledges receipt and returns credits, the corresponding credit limits are incremented accordingly.

Credit updates are transmitted by the DUT only for TLP categories whose credit limits have changed since the last update. The signal p<n>_ss_app_st_txcrdt_tvalid of the DUT is asserted only when the associated credit value in p<n>_ss_app_st_txcrdt_tdata has increased for a specific TLP category. The Transmit Flow Control module interfaces with the DUT’s credit signals to manage and maintain an accurate transmit credit tracking for efficient data flow.

Level Two Title