GTS AXI Multichannel DMA IP for PCI Express* User Guide

ID 847470
Date 8/25/2025
Public
Document Table of Contents

4.4.2. PCIe AXI-Stream RX Interface (ss_rx_st)

The packet from the link is received on this interface with separate header and data interfaces. These interfaces support single segments with data widths of 16 bytes (128 bits), 32 bytes (256 bits), and 64 bytes (512 bits). These interfaces should be connected to the corresponding AXI-Stream RX interface of the GTS AXI Streaming IP.

For information of this interface, refer to AXI4-Stream Receive (RX) Interface.

Interface clock: axi_st_clk

DWIDTH depends on the PCIe mode selected:

  • 512 bits for Gen4 1x8
  • 256 bits for Gen4 1x4
  • 128 bits for Gen3 1x4
Table 35.  PCIe AXI-Stream RX Interface
Signal Name Direction Description
ss_app_st_rx_tvalid Input Indicates that the source is driving a valid transfer.
app_ss_st_rx_tready Output Indicates that the sink can accept a transfer in the current cycle.
ss_app_st_rx_tdata[DWIDTH-1:0] Input Data bus used to provide the data that is passing across the interface.
ss_app_st_rx_tkeep[DWIDTH/8-1:0] Input

A byte qualifier used to indicate whether the content of the associated byte is valid.

The invalid bytes are allowed only during the ss_app_st_rx_tlast cycle.

Note: Sparse tkeep is not supported.

ss_app_st_rx_tlast Input Indicates End of Data/Command Transmission.
ss_app_st_rx_tuser_hvalid Input Indicates the ss_app_st_rx_tuser_hdr is valid in the respective segment.
ss_app_st_rx_tuser_hdr[DWIDTH-1:0] Input

Carries the header format for the current cycle of data transfer.