2012年11月13日 · The description of the packet above was defined as a Transaction Layer Packet (TLP), which relates to PCIe’s uppermost layer. The Data Link layer is responsible for making sure that every TLP arrives to its destination correctly.

2019年7月29日 · Provides: Format, TLP Packet Type, Traffic Class info, Attributes, T Heads (Presence of TLP Prefix, if present), TLP Digest, End Point (TLP is Normal or Poisoned), Address Translation (When memory is available).

Arria® 10 and Cyclone® 10 GX Avalon® Streaming Interface for PCI Express* User Guide

A TLP payload can theoretically be as big as 1023 DWs, pretty handy for burst reads and writes, although PCs can limit the maximum size to a lower value (32 DWs is typical). For more information, check the official PCI Express specification by googling something like PCI_Express_Base_11.pdf

2024年3月26日 · When the device receives the requestor packet, the device responds to the memory request with a Memory Read Response TLP. This TLP contains the result of the read from the device’s memory space given the address and size in the original requestor packet.

2023年11月28日 · Transaction Layer Packets (TLPs) facilitate the transfer of data between PCIe devices via requests and completions. The size of the TLP is determined by its type and the data it carries. Its structure is designed to be straightforward for easy decoding by the receiving device.

PCIe is a serial protocol that is accessible to transfer data between two devices. It is comprised of three layers namely Transaction Layer(TL), Data Link Layer(DLL), and Physical Layer(PL). The transaction layer is the topmost layer of the PCIe, which intermediates between the core logic of the external device and the DLL of the PCIe.

2012年11月13日 · The PCIe standard allocates a certain number of bits for each credit type counter and its limit (8 bits for header credits, 12 bits for data credits), knowing that they will overflow pretty soon. This overflow is worked around by making the comparison between each counter and its limit with straightforward modulo arithmetic.

2022年8月4日 · For the most part, the TLP layers is involved in reading and writing to various addressed spaces: memory, I/O and configuration, each with their own transaction layer packet (TLP) types.

2017年8月21日 · The PCI-E Maximum Payload Size BIOS feature determines the maximum TLP (Transaction Layer Packet) payload size used by the PCI Express controller. The TLP payload size determines the amount of data transmitted within each data packet.