Scalable Scatter-Gather DMA Intel® FPGA IP User Guide

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

3.1.1.1. PCIe* TLP Constructor

The TLP constructor module is responsible to insert the PCIe* header fields based on the outgoing memory read or write request packet type. After appending is done, the corresponding packet is forwarded to the subsequent modules.

The following table lists header fields, their byte position, and bit position of app_ss_st_tx_tdata signal of AXI-ST TX interface.

Table 6.  TLP Header Format
Tdata Header Byte Index Header Fields Bits Tdata Bit Position End Tdata Bit Position Start
Byte 15 - Byte 0 PCIe Header 128 127 0
Byte 19 - Byte 16 Prefix 24 151 128
Prefix Type 5 156 152
Prefix Present 1 157 157
Reserved 2 159 158
Byte 23 - Byte 20 PF Number 3 162 160
VF Number 11 173 163
VF Active 1 174 174
Bar number 4 178 175
Slot number 5 183 179
Reserved 8 191 184
Byte 31 - Byte 24 Reserved 64 255 192
Note: SSGDMA IP does not use TLP prefix and configures the subsequent Prefix, Prefix Type and Prefix Present fields as 0.