AMX DESIGN XPRESS V 1.5 - PROGRAMMER GUIDE User's Guide download pdf (Page 229)

Chapter 17: Testbench and Design Example 17–7

Chaining DMA Design Examples

December 2013 Altera Corporation Cyclone V Hard IP for PCI Express

User Guide

The chaining DMA design example hierarchy consists of these components:

■ A DMA read and a DMA write module

■ An on-chip Endpoint memory (Avalon-MM slave) which uses two Avalon-MM

interfaces for each engine

■ The RC slave module is used primarily for downstream transactions which target

the Endpoint on-chip buffer memory. These target memory transactions bypass

the DMA engines. In addition, the RC slave module monitors performance and

acknowledges incoming message TLPs.

Each DMA module consists of these components:

■ Control register module—The RC programs the control register (four dwords)

to start the DMA.

■ Descriptor module—The DMA engine fetches four dword descriptors from

BFM shared memory which hosts the chaining DMA descriptor table.

■ Requester module—For a given descriptor, the DMA engine performs the

memory transfer between Endpoint memory and the BFM shared memory.

1 ... 228 229 230 ... 288

No comments

AMX DESIGN XPRESS V 1.5 - PROGRAMMER GUIDE User's Guide Page 229