This page gives an overview of the bare-metal driver support for the Xilinx® LogiCORE™ IP AXI MultiChannel Direct Memory Access (AXI MCDMA) soft IP.

Introduction

The AXI MCDMA core is a soft Xilinx IP core for use with the Xilinx Vivado® Design Suite. The AXI MCDMA provides high-bandwidth direct memory access between memory and AXI4-Stream target peripherals. The AXI MCDMA core provides Scatter Gather interface with Multiple Channel support with independent configuration.
For more information, please refer to the AXI MCDMA product page which includes links to the official documentation and resource utilization.

Driver Sources

The source code for the driver is included with the Vitis Unified Software Platform installation, as well as being available in the Xilinx Github repository.

Driver Name	Path in Vitis	Path in Github
mcdma	<Vitis Install Directory>/data/embedded/XilinxProcessorIPLib/drivers/mcdma_<version>	https://github.com/Xilinx/embeddedsw/tree/master/XilinxProcessorIPLib/drivers/mcdma

Note: To view the sources for a particular release, use the rel-version tag in github. For example, for the 2020.1 release, the proper version of the code is: https://github.com/Xilinx/embeddedsw/tree/xilinx-v2020.1/XilinxProcessorIPLib/drivers/mcdma

The driver source code is organized into different folders. The table below shows the axi mcdma driver source organization.

Directory	Description
doc	Provides the API and data structure details
data	Driver .tcl, .mdd file and .yaml files
examples	Example applications that show how to use the driver features
src	Driver source files, make and cmake files

Note: AMD Xilinx embeddedsw build flow is changed from 2023.2 release to adapt to the new system device tree based flow. For further information, refer to the wiki page Porting embeddedsw components to system device tree (SDT) based flow - Xilinx Wiki - Confluence (atlassian.net).

The .yaml(in data folder) and CMakeLists.txt(in src folder) files are needed for the System Device Tree based flow. The Driver .tcl and .mdd files are for the older build flow which will be deprecated in the future.

Driver Implementation

For a full list of features supported by this IP, please refer to the AXI MCDMA product page.

Features

The AXI MCDMA Standalone driver supports the following features:

Supports upto 16 Channels
Supports Scatter/Gather Direct Memory Access (DMA)
Supports 64-bit Addressing
Supports Optional Data Re-Alignment Feature
Supports per channel interrupt
Supports AXIS Control and Status Streams.

Known Issues and Limitations

All IP features are supported

Example Design Architecture

The examples assumes AXI MCDMA IP is configured in loopback mode.

Example Applications

Refer to the driver examples directory for various example applications that exercise the different features of the driver. Each application is linked in the table below. The following sections describe the usage and expected output of the various applications. These example applications can be imported into the Vitis IDE from the Board Support Package settings tab.

Links to Examples

Examples Path: https://github.com/Xilinx/embeddedsw/tree/master/XilinxProcessorIPLib/drivers/mcdma/examples

Test Name	Example Source	Description
Packet transfer with Interrupts	xmcdma_interrupt_example.c	This example demonstrates how to use axi mcdma driver on axi mcdma core to transfer packets in interrupt mode.
Packet transfer with Polling	xmcdma_polled_example.c	This example demonstrates how to use axi mcdma driver on axi mcdma core to transfer packets in polled mode

Example Application Usage

Packet transfer with Interrupts

This example demonstrates how to use axi mcdma driver on axi mcdma core to transfer packets in interrupt mode.

Expected Output

--- Entering main() ---
AXI MCDMA SG Interrupt Test passed
--- Exiting main() ---

Packet transfer with Polling

This example demonstrates how to use axi mcdma driver on axi mcdma core to transfer packets in polled mode

Expected Output

--- Entering main() ---
AXI MCDMA SG Polling Test passed
--- Exiting main() ---

Change Log

2024.1

https://github.com/Xilinx/embeddedsw/blob/xilinx_v2024.1/doc/ChangeLog#L478

2023.2

https://github.com/Xilinx/embeddedsw/blob/xlnx_rel_v2023.2/doc/ChangeLog#L560

2023.1

https://github.com/Xilinx/embeddedsw/blob/xilinx_v2023.1/doc/ChangeLog#L101

2022.2

https://github.com/Xilinx/embeddedsw/blob/xilinx_v2022.2/doc/ChangeLog#L111

2022.1

https://github.com/Xilinx/embeddedsw/blob/xilinx_v2022.1/doc/ChangeLog#L52

2021.2

None

2021.1