BSP User Guide

VME Bus Operation

5.4 Universe DMA Functionality

The Universe includes a built-in DMA controller that enables high-speed block transfers between

PCI and VME. This enables high-throughput block transfers without the involvement of the CPU.

The BSP includes a module, called uniDmaLib, which provides functions for interfacing with the

Universe DMA controller. Both direct DMA transfers and chained DMA transfers are supported by this module.

Universe DMA Driver

In order to use the Universe DMA controller module of the BSP, include the following line at the top of the application source file:

#include "uniDmaLib.h"

The object module <bsp directory>/mdrv/lib/uniDmaLib.o must be loaded prior to loading the application. The uniDmaLib.o module may also be directly linked with the application.

The Universe DMA controller supports 2 modes of operation:

1.

Direct mode transfers a single block of data between the PCI bus and the VME bus. Use uniDmaDirect

function to initiate a direct DMA transfer.

2.

Linked list (chained) mode transfers one or multiple blocks of data between the PCI bus and the

VME bus. The DMA engine uses DMA command packets to describe how to transfer each block of data. Use uniDmaChainCmdPkCreate

to create DMA command packets. Use the uniDmaChain

function to initiate a chained DMA transfer. Use uniDmaChainStop

to stop a chained DMA transfer.

Use the uniDmaNotifyFncSet

to specify a function to be called when the DMA engine is done or halts due to an error situation.

Universe DMA Interface Functions uniDmaLibInit

STATUS uniDmaLibInit (int show_release)

Synopsis

Description

This function initializes the Universe DMA library. If the parameter show_release is

TRUE, the driver release info is printed to the console.

OK or ERROR

Returns

none

Notes

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M5000 Series: BSP User Guide Issued June 20, 2007