AM243x MCU+ SDK  08.06.00
EtherNet/IP Adapter FWHAL

Table of Contents

Introduction

This software is designed for the TI SoCs with PRU-ICSS IP to enable customers add EtherNet/IP Adapter protocol support to their system. It implements EtherNet/IP + PTP + DLR functionality and provides EtherNet/IP ASIC like functionality integrated into TI SoCs.

Software Architecture

EtherNet/IP firmware for PRU-ICSS is a black box product maintained by TI. EtherNet/IP Adapter FWHAL(Firmware and Hardware Abstraction Layer) allows loading and running EtherNet/IP firmware and acts as an interface with the firmware. FWHAL implements the key interface between EtherNet/IP Adapter firmware and EtherNet/IP Adapter stack.

PRU-ICSS EtherNet/IP Adapter Firmware

Features Supported

  • Integrated two-port cut-through switch
    • 100 Mbps, 10Mbps
    • Full Duplex, Half Duplex
  • Quality of Service (QoS)
    • Four priority receive queues on host port, each queue 6 KB in size
    • Four priority transmit queues on each physical port, each queue 3 KB in size
  • DLR – Device Level Ring
    • 200us beacon interval
    • 400us beacon timeout
    • Self-Configuring
  • PTP/1588 - Time Synchronization
    • E2E mode supported
    • CIP Sync capable
    • Transparent and Ordinary Clock
  • 1 ms buffering per port
  • 802.1d learning bridge for received source MAC addresses
    • 1024 addresses per port
    • APIs for port state configuration and flushing learning table upon change in network topology
    • Switch address learned table (FDB) is flushed in 2.4 us
  • Multicast and Broadcast storm prevention per port
  • Interrupt for Link loss detection
    • Callback APIs to perform tasks related to change in network topology
  • Statistics
    • Media counters supported per port
    • Interface counters supported per port
  • LLDP Support
  • Firmware based on 200 MHz clock frequency for PRU-ICSS Core Clock and IEP Clock

Known Issues

Record ID Details Workaround
PINDSW-4982 SQE and Carrier Sense Errors counters not supported in EtherNet/IP

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Important Files and Directory Structure

Folder/Files Description
${SDK_INSTALL_PATH}/examples/industrial_comms
ethernetip_adapter_demo EtherNet/IP Adapter Examples (based on pre-integrated stack)
${SDK_INSTALL_PATH}/source/industrial_comms/ethernetip_adapter
icss_fwhal/firmware Firmware for the PRU cores in PRU-ICSS. Firmware Version : 5.2.9
icss_fwhal/lib/ FWHAL library for EtherNet/IP Adapter
icss_fwhal/*.c FWHAL source files
icss_fwhal/*.h FWHAL interface files
stack

Stack header files and stack library

Terms and Abbreviations

Abbreviation Expansion
PRU-ICSS Programmable Real-Time Unit Industrial Communication Subsystem
DLR Device Level Ring (A redundancy protocol)
PTP Precision Time Protocol
OC Ordinary Clock
TC Transparent Clock
E2E End to End

API Documentation

Please see APIs for EtherNet/IP Adapter FWHAL for API documentation. It is recommended to use these FWHAL APIs in the stack adaptation files.

Procedure to kick-off the EtherNet/IP Adapter

  • Initialize ICSS-EMAC to work as a switch
  • Initialize the required tasks and interrupts
  • Initialize the EtherNet/IP FWHAL, PTP, DLR and PRU-ICSS INTC
  • Load EtherNet/IP firmware into PRUs of PRU-ICSS
  • Initialize the EtherNet/IP adapter stack
  • Start firmware
  • Handle the events as needed. The Event/ISR definitions are available in developer guide(provide a link here), these have respective callbacks that can be registered to custom stack APIs.

Integration with ICSS-EMAC

Ethernet/IP Adapter examples uses the ICSS-EMAC as its base switch layer. The PRU Firmware provides switch functionality and additional PTP and DLR functionalities. The NRT(non-real time) traffic is handled by ICSS-EMAC, wherein the packets are forwarded either to the TCP stack or a custom callback (configurable in ICSS-EMAC).

Interface with ICSS-EMAC

Ethernet/IP packets are standard ethernet frames and all protocol specific data is embedded in TCP/IP payload. Hence the standard switch model applies. Packets are segregated based on VLAN PCP field. The 8 priorities which map to 4 queues, with highest and next highest priorities going to Queue 0 and Queue 1 and so on. If PCP field does not exist, then frames go to Queue 3. All queues except the highest priority queue forward the frames to TCP/IP stack. Further if packet type does not match PTP or DLR then that frame goes to TCP/IP stack. The highest priority queues are used for PTP and DLR. These packets are directly forwarded to the registered callback in ICSS-EMAC (using rxRTCallBack).

Interrupts

EtherNet/IP firmware generates the following interrupts.

8 Host Interrupts (Host Interrupts 2 through 9) are exported from the PRU_ICSSG internal INTC for signaling the device level interrupt controllers. PRU_EVTOUT0 to PRU_EVTOUT7 correspond to these eight interrupts in the following table. Please check PRUICSS Interrupt Controller section for more details.

Name Host Interrupt Description
Frame Receive PRU_EVTOUT0 Notifies host when firmware has stored a frame in host receive queue
DLR Port 0 Interrupt PRU_EVTOUT1 Raised when there is a state change in DLR on Port 0
DLR Port 1 Interrupt PRU_EVTOUT2 Raised when there is a state change in DLR on Port 1
Tx Callback Interrupt PRU_EVTOUT3 Raised when a PTP/1588 frame which requires Tx Timestamping is sent out
DLR Beacon Timeout Interrupt for Port 0 PRU_EVTOUT4 Raised when the beacon timeout timer on Port 0 expires
DLR Beacon Timeout Interrupt for Port 1 PRU_EVTOUT7 Raised when the beacon timeout timer on Port 1 expires
Link Change PRU_EVTOUT6 Interrupt is raised when the link on Ethernet PHY comes up or goes down

Device Level Ring

Device Level Ring on EtherNet/IP firmware provides redundancy to the switch implementation. It is a beacon based implementation with support for a minimum beacon of 200us and timeout of 400us. More information is available in developer guide(provide a link here).

IEEE PTP-1588 Implementation

PTP/1588 on EtherNet/IP provides time synchronization support. The implementation is driven by CIP Sync requirements which require End to End clock support over UDP (Annex D). EtherNet/IP adapter application supports both OC and TC implementations along with syntonization.

Additional References

Please refer to below documents to understand more about EtherNet/IP Adapter on TI platforms and EtherNet/IP Adapter protocol specifications.

Document Description
EtherNet/IP on TI's Sitara processors Application note by TI on the EtherNet/IP Adapter implementation on TI's Sitara Processors.

See also