Multi Channel DMA Intel® FPGA IP for PCI Express User Guide

ID 683821
Date 4/20/2022
Public

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Document Table of Contents

8.4.3.1. Host to Device Flow

Figure 50. H2D Flow

When user space application attempts to send one packet to network device

  1. Application generates the data and the data can be copied to the kernel
  2. TCP/IP Stack creates the skb and calls the transmit handler registered by ndo_start_xmit callback overriden by MCDMA network driver
  3. Driver retrieves the physical address or I/O Virtual address,, loads the descriptor and submits the DMA transactions

When descriptor processing is completed

  1. Hardware completes the transaction and notifies the host via an interrupt
  2. MCDMA driver receives the completion and frees the allocated skb