Dma write cycles, Dma write cycles -8 – Altera Arria 10 Avalon-MM User Manual

Page 158

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• The DMA issues an MSI when the last descriptor has completed.

• The data written back to BFM is checked against the data that was read from the BFM.

• The driver programs the DMA to perform a test that demonstrates downstream access of the

DMA Endpoint memory.

Note: Edit this file if you want to add your own custom PCIe transactions. Insert your own custom

function after the

find_mem_bar

function. You can use the functions in the BFM Procedures and

Functions section.

Related Information

BFM Procedures and Functions

on page 14-22

DMA Write Cycles

The procedure

dma_wr_test

used for DMA writes uses the following steps:

1. Configures the BFM shared memory. Configuration is accomplished with three descriptor tables

described below.

Table 14-2: Write Descriptor 0

Offset in BFM in

Shared Memory

Value

Description

DW0

0x810

82

Transfer length in dwords and control bits as described in

Bit Definitions for the Control Field in the DMA Write

Control Register and DMA Read Control Register.

DW1

0x814

3

Endpoint address

DW2

0x818

0

BFM shared memory data buffer 0 upper address value

DW3

0x81c

0x1800

BFM shared memory data buffer 1 lower address value

Data

Buffer 0

0x1800

Increment by 1

from 0x1515_

0001

Data content in the BFM shared memory from address:

0x01800–0x1840

Table 14-3: Write Descriptor 1

Offset in BFM

Shared Memory

Value

Description

DW0

0x820

1,024

Transfer length in dwords and control bits as described in

Bit Definitions for the Control Field in the DMA Write

Control Register and DMA Read Control Register .

DW1

0x824

0

Endpoint address

14-8

DMA Write Cycles

UG-01145_avmm

2015.05.14

Altera Corporation

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