Introduction

This page provides details related to the standalone emacps driver. This driver supports GEM on Zynq, Zynq Ultrascale+ MPSoC and Versal. For more information, please refer to GEM Ethernet chapter in Zynq TRM (UG585), ZynqMP TRM (UG1085) or Versal TRM (AM011).

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
emapcs	<Vitis Install Directory>/data/embedded/XilinxProcessorIPLib/drivers/emacps	https://github.com/Xilinx/embeddedsw/tree/master/XilinxProcessorIPLib/drivers/emacps

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_v2021.1/XilinxProcessorIPLib/drivers/emacps

The driver source code is organized into different folders. The table below shows the emacps 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 GEM Chapter in Zynq TRM (UG585), ZynqMP TRM (UG1085) or Versal TRM (AM011) for respective devices.

Features

Controller/Driver features supported

10/100/1000 speeds, phy/external loop back (supported in emacps
PHY management
DMA, Packet buffer support, Checksum offload, FCS stripping, programmable IPG, multicasting, promiscuous and broadcast modes.
Flow control and half duplex features are supported by controller but not demonstrated in the examples.
ZynqMP and Versal only: 64 bit descriptor support, Priority queue support, Jumbo frame support, CCI support

PHY configurations

emacps driver supports the following PHY configurations:

Family	PHY	Support
Zynq	RGMII	Yes - supported in HW and driver
ZynqMP	RGMII	Yes - supported in HW and driver
ZynqMP	SGMII	Yes - supported in HW and driver
Versal	RGMII	Yes - supported in HW and driver

Known Issues and Limitations

The following features are not supported:
- External FIFO interface - this driver only targets DMA
- Partial store and forward not supported
Clock change is not automatically handled in the example in SDT flow currently. Clock registers can still be manually modified by users. Support for automatically handling this through baremetal clocking framework will be added in an upcoming release.

Interop

PHY device Marvell 88E1116 has been tested on Zynq evaluation board
PHY devices Marvell 88E1512, TI DP83867 (RGMII and SGMII), VSC8211 and RTL8211 have been tested on ZynqMP.
PHY devices Marvell 88E1512, TI DP83867, VSC8531_02 and RTL8211DN have been tested on Versal.

Example Applications

Emacps driver supports a DMA based loopback example and it describes how its different features can be exercised. 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/emacps

Test Name

Example Source

Description

Emacps DMA loopback example

xemacps_example_intr_dma.c

xemacps_example.h

xemacps_example_util.c

Emacps basic DMA loopback examples sends and receives a single frame in loopback mode.
Refer to https://github.com/Xilinx/embeddedsw/blob/master/XilinxProcessorIPLib/drivers/emacps/examples/readme.txt for more information.

Note: emacps 1588 examples were deprecated as they were originally added as a reference for Zynq-7000 but the timestamping logic in that version of the IP has issues, rendering this feature unusable. These examples were removed in 2021.1 release.

Example Application Usage

Emacps DMA loopback example

Emacps basic DMA loopback examples sends and receives a single frame in loopback mode.

Expected Output

Entering into main()
Success in examples

Example Design Architecture

NA

Performance

Standalone ethernet performance is benchmarked with the use of light weight IP library and application. Please refer to
http://www.wiki.xilinx.com/Standalone+LWIP+library#Performance