LogiCORE IP Gigabit Ethernet MAC
UG144 April 24
 Gigabit Ethernet MAC v8.5 User Guide
 Revision History
Date Version Revision
 DIS Product
 Table of Contents
 Designing with the Core
 Configuration and Status
 Appendix C Calculating DCM Phase-Shifting
 1Block Diagram
Schedule of Figures
 2External Gmii Receiver Logic for Spartan-3, Spartan-3E,
 Figure A-2Frame Transfer across LocalLink Interface
 DIS Product
 Schedule of Tables
 Clocking and Resetting Interfacing to Other Cores
 Guide Contents
About This Guide
 Conventions
Typographical
Preface About This Guide
Convention Meaning or Use Example
 Online Document
List of Acronyms
Conventions
Acronym Spelled Out
 Preface About This Guide Acronym Spelled Out
Vhdl
 Related Xilinx Ethernet Products and Services
Introduction
About the Core
Recommended Design Experience
 Specifications
Technical Support
Feedback
Gemac Core
 Core Architecture
System Overview
 Core Components
 Core Interfaces
Core Interfaces
Gmac Core with Optional Management Interface
 Core Architecture
 Core Interfaces
 Client Side Interface
Transmitter Interface
 Receiver Interface
Flow Control Interface
 Management Interface Optional
MAC Unicast Address Optional
 Configuration Vector Optional
Asynchronous Reset
7Reset Signal Direction Clock Domain Description
Physical Side Interface
 Mdio Interface
 Generating the Core
Graphical User Interface
 Parameter Values in the XCO File
 Output Generation
 Generating the Core
 Using the Example Design as a Starting Point
Designing with the Core
General Design Guidelines
Design Steps
 Designing with the Core
11-Gigabit Ethernet MAC Core Example Design
 General Design Guidelines
Know the Degree of Difficulty
Implementing the 1-Gigabit Ethernet MAC in Your Application
 Recognize Timing Critical Signals
Keep it Registered
Use Supported Design Flows
Make Only Allowed Modifications
 Using the Client Side Data Path
1Abbreviations Used in Timing Diagrams Definition
Receiving Inbound Frames
Normal Frame Reception
 Using the Client Side Data Path
Rxgoodframe, rxbadframe timing
 Frame Reception with Errors
Receiving Inbound Frames
 Client-Supplied FCS Passing
Vlan Tagged Frames
 Length/Type Field Error Checks
Enabled
Disabled
Maximum Permitted Frame Length
 Receiver Statistics Vector
5Receiver Statistics Vector Timing
 DIS Product
 Length see Maximum Permitted Frame
 Transmitting Outbound Frames
Normal Frame Transmission
Padding
Transmitting Outbound Frames
 Client Underrun
7Frame Transmission with Client-supplied FCS
 Inter-Frame Gap Adjustment
9Transmission of a Vlan Tagged Frame
 10Inter-Frame Gap Adjustment
Transmitter Statistics Vector
 Name
 Bit 31 is equivalent to bit
 Flow Control Requirement
Using Flow Control
Overview of Flow Control
 Using Flow Control
Flow Control Basics
 Pause Control Frames
Overview of Flow Control
 Flow Control Operation of the Gemac
Transmitting a Pause Control Frame
Core-initiated Pause Request
Client Initiated Pause Request
 Receiving a Pause Control Frame
Core Initiated Response to a Pause Request
Client Initiated Response to a Pause Request
Flow Control Operation of the Gemac
 Flow Control Implementation Example
Method
 Flow Control Implementation Example
4Flow Control Implementation Triggered from Fifo Occupancy
 Using Flow Control
 Gmii Transmitter Logic
Using the Physical Side Interface
Implementing External Gmii
 Using the Physical Side Interface
1External Gmii Transmitter Logic
 Implementing External Gmii
Gmii Receiver Logic
Spartan-3, Spartan-3E, Spartan-3A and Virtex-4 Devices
 DCM Reset circuitry
 Virtex-5 Devices
3External Gmii Receiver Logic for Virtex-5 Devices
 Implementing External Rgmii
Rgmii Transmitter Logic
 Virtex-4 Devices
Implementing External Rgmii
 5External Rgmii Transmitter Logic in Virtex-4 Devices
 6External Rgmii Transmitter Logic in Virtex-5 Devices
 Rgmii Receiver Logic
 7External Rgmii Receiver Logic
 Virtex-4 Devices
 8External Rgmii Receiver Logic for Virtex-4 Devices
 9External Rgmii Receiver Logic for Virtex-5 Devices
 Rgmii Inband Status Decoding Logic
10RGMII Inband Status Decoding Logic
 Connecting the Mdio to an External PHY
Using the Mdio interface
Connecting the Mdio to an Internally Integrated PHY
 Host Clock Frequency
Configuration and Status
Using the Optional Management Interface
 2Configuration Registers Address Description
Configuration Registers
Configuration and Status
 Receiver Configuration
Using the Optional Management Interface
3Receiver Configuration Word Bit Default Description
Receiver Configuration Word
 Transmitter Configuration
Interframe Gap Adjust Enable If ‘1,’ the transmitter will
 Flow Control Configuration
6Flow Control Configuration Word Bit Default Description
 Mdio Configuration
Address Filter Configuration
 Writing and Reading to and from the Configuration Registers
10Address Table Configuration Word Bits Default Description
11 Address Table Configuration Word
12Address Filter Mode Bits Default Description
 1Configuration Register Write Timing
 Accessing the Address Table
3Address Table Write Timing
 Mdio Interface
Introduction to Mdio
 Write Transaction
5Typical MDIO-managed System
 Accessing Mdio With Gemac
Read Transaction
 8MDIO Access through Management Interface
 Access without the Management Interface
Pause frame MAC Source Address470
 Transmitter Interframe Gap Adjust Enable
 Receive Flow Control Enable . When this bit
 Constraining the Core
Required Constraints
 Period Constraints for Clock Nets
Constraining the Core
 Timespecs for Critical Logic within the Core
Required Constraints
 Gmii IOB Constraints
Constraints when Implementing an External Gmii
Timespecs for Reset Logic within the Core
 Gmii Input Setup/Hold Timing
1Input Gmii Timing Symbol Min Max Units
 Virtex-5 Devices
 Non-Virtex-5 devices
Understanding Timing Reports for Gmii Setup/Hold Timing
Virtex-5 devices with Delayed Data/Control
 Virtex-5 Devices with Delayed Clock
 Constraints when Implementing an External Rgmii
Rgmii IOB Constraints
 Rgmii Input Setup/Hold Timing
2Input Rgmii Timing Symbol Min Typical Units
 Spartan-3, Spartan-3E, Spartan-3A, and Virtex-4 Devices
 Rgmii DDR Constraints
 Understanding Timing Reports for Rgmii Setup/Hold timing
 106
 4Timing Report Setup/Hold Illustration
 108
 Clocking and Resetting
Clocking the Core
With Internal Gmii
With External Gmii
 Clocking and Resetting
Multiple Cores
With Rgmii
Standard Clocking Scheme
 Multiple Cores
3Clock Management Logic with External Gmii Multiple Cores
 Reset Conditions
4Clock Management Logic with External Rgmii Multiple Cores
 Interfacing to Other Cores
Ethernet 1000Base-X PCS/PMA or Sgmii Core
 Integration to Provide 1000BASE-X PCS with TBI
Interfacing to Other Cores
 Ethernet 1000Base-X PCS/PMA or Sgmii Core
 116
 Virtex-5 LXT and SXT Devices
GTP
 Virtex-5 FXT Devices
Clkdv
 Ethernet Statistics Core
Ethernet Statistics Core
Integration to Provide Sgmii Functionality
 120
 Configuration Miim access Statistics Read
 122
 Using the Simulation Model
Implementing Your Design
Pre-implementation Simulation
Synthesis
 Implementation
XST-Verilog
Generating the Xilinx Netlist
Mapping the Design
 Post-Implementation Simulation
Placing-and-Routing the Design
Static Timing Analysis
Generating a Bitstream
 Using the Model
Other Implementation Information
 Using the Client-Side Fifo
GMII/RGMII
 Transmit Fifo
Appendix a Using the Client-Side Fifo
Interfaces
 Receive Fifo
Interfaces
 Overview of LocalLink Interface
Data Flow
 Functional Operation
Functional Operation
Clock Requirements
 Expanding Maximum Frame Size
User Interface Data Width Conversion
 Hardware Verification
Core Verification, Compliance, and Interoperability
Verification by Simulation
 134
 Finding the Ideal Phase-Shift
Calculating DCM Phase-Shifting
DCM Phase-Shifting
 Appendix C Calculating DCM Phase-Shifting
 Receive Path Latency
Core Latency
Transmit Path Latency
 Appendix D Core Latency