E-Tile Transceiver PHY User Guide

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ID 683723
Date 7/08/2024
Public
Document Table of Contents
Document Table of Contents x
1. E-Tile Transceiver PHY Overview 2. Implementing the Transceiver PHY Layer 3. E-Tile Transceiver PHY Architecture 4. Clock Network 5. PMA Calibration 6. Resetting Transceiver Channels 7. Dynamic Reconfiguration 8. Dynamic Reconfiguration Examples 9. Register Map 10. Debugging E-Tile Transceiver Links A. E-Tile Channel Placement Tool B. PMA Direct PAM4 30 Gbps to 57.8 Gbps Implementation C. Signal Detect Algorithm D. Detailed Steps for Reconfiguring from Mission Mode to Channel Protection Mode E. Detailed Steps for Reconfiguring from Channel Protection Mode to Mission Mode F. Hold Timing Violation
1. E-Tile Transceiver PHY Overview x
1.1. Supported Features 1.2. E-Tile Layout in Stratix® 10 Device Variants 1.3. E-Tile Layout in Agilex™ 7 F-Series Device Variants 1.4. Transceiver Counts 1.5. E-Tile Building Blocks 1.6. E-Tile Transceiver PHY Overview Revision History
1.2. E-Tile Layout in Stratix® 10 Device Variants x
1.2.1. Stratix® 10 TX H-Tile and E-Tile Configurations 1.2.2. Stratix® 10 MX H-Tile and E-Tile Configurations 1.2.3. Stratix® 10 DX P-Tile and E-Tile Configurations
1.5. E-Tile Building Blocks x
1.5.1. GXE Transceiver Channel 1.5.2. GXE Channel Usage 1.5.3. Reference Clocks 1.5.4. Ethernet Hard IP (EHIP) 1.5.5. Supported Applications/Modes 1.5.6. Feature Comparison Between Transceiver Tiles
2. Implementing the Transceiver PHY Layer x
2.1. Transceiver Design Flow in the Native PHY IP Core 2.2. Configuring the Native PHY IP Core 2.3. Implementing the Transceiver PHY Layer Revision History
2.1. Transceiver Design Flow in the Native PHY IP Core x
2.1.1. E-Tile Native PHY IP Core
2.2. Configuring the Native PHY IP Core x
2.2.1. General and Datapath Parameters 2.2.2. PMA Parameters 2.2.3. Core Interface Options 2.2.4. PMA Interface 2.2.5. PMA Adaptation Parameters 2.2.6. Reed Solomon Forward Error Correction (RS-FEC) Parameters 2.2.7. Reset Parameters 2.2.8. Dynamic Reconfiguration Parameters 2.2.9. Deskew Logic 2.2.10. Port Information 2.2.11. PLL Mode 2.2.12. Simplex Support
2.2.2. PMA Parameters x
2.2.2.1. TX PMA Options 2.2.2.2. TX PMA Pre-equalization 2.2.2.3. RX PMA Options 2.2.2.4. RX PMA Optional Ports
2.2.3. Core Interface Options x
2.2.3.1. Core Interface Parameters 2.2.3.2. TX Clock Options 2.2.3.3. RX Clock Options 2.2.3.4. Latency Measurement Options
2.2.4. PMA Interface x
2.2.4.1. PMA Interface Options 2.2.4.2. Gearbox 64/66
2.2.6. Reed Solomon Forward Error Correction (RS-FEC) Parameters x
2.2.6.1. Fibre-Channel and CPRI Modes 2.2.6.2. 128 GFC Mode 2.2.6.3. 25 GbE FEC Direct Mode 2.2.6.4. Interlaken Mode
3. E-Tile Transceiver PHY Architecture x
3.1. Physical Medium Attachment (PMA) Architecture 3.2. Physical Coding Sublayer (PCS) Architecture 3.3. Reed Solomon Forward Error Correction (RS-FEC) Architecture 3.4. E-Tile Transceiver PHY Architecture Revision History
3.1. Physical Medium Attachment (PMA) Architecture x
3.1.1. Transmitter PMA 3.1.2. Receiver PMA 3.1.3. PMA Tuning 3.1.4. Duplex Adaptation Flow 3.1.5. RX Simplex Adaptation Flow 3.1.6. Dynamic Reconfiguration Adaptation Flow 3.1.7. Loopback modes 3.1.8. PMA Interface 3.1.9. TX PMA Bonding 3.1.10. Unused Transceiver Channels 3.1.11. Low Power Mode (LPM)
3.1.1. Transmitter PMA x
3.1.1.1. High Speed Differential Transmitter 3.1.1.2. Gray Encoder/Precoder 3.1.1.3. Serializer 3.1.1.4. Data Pattern Generation
3.1.1.1. High Speed Differential Transmitter x
3.1.1.1.1. High Speed Transmitter Line Buffer 3.1.1.1.2. TX Equalizer
3.1.2. Receiver PMA x
3.1.2.1. Receiver Buffer 3.1.2.2. Clock Data Recovery (CDR) Block 3.1.2.3. Input Sampler 3.1.2.4. Deserializer 3.1.2.5. Data Pattern Verifier
3.1.2.1. Receiver Buffer x
3.1.2.1.1. Programmable Termination Modes 3.1.2.1.2. RX Adaptation Modes
3.1.3. PMA Tuning x
3.1.3.1. Purpose of PMA Tuning 3.1.3.2. PMA Bring Up Flow 3.1.3.3. PMA Tuning Guidelines 3.1.3.4. General PMA Tuning Guidelines
3.1.7. Loopback modes x
3.1.7.1. Internal Serial Loopback Path 3.1.7.2. Reverse Parallel Loopback Path
3.1.9. TX PMA Bonding x
3.1.9.1. Transceiver Interface Deskew Logic 3.1.9.2. Dedicated Balanced PLL Reference Clock Tree
3.1.10. Unused Transceiver Channels x
3.1.10.1. Unused Transceiver Channels in a Used Tile 3.1.10.2. Unused Transceiver Channels in Completely Unused Tiles 3.1.10.3. Unused Transceiver Channels in High-Speed PAM4 Mode 3.1.10.4. Reconfiguring from Mission Mode to Channel Protection Mode 3.1.10.5. Reconfiguring from Channel Protection Mode to Mission Mode
3.3. Reed Solomon Forward Error Correction (RS-FEC) Architecture x
3.3.1. RS-FEC Modes
4. Clock Network x
4.1. Reference Clock Pins 4.2. Core Clock Network Use Case 4.3. Clock Network Revision History
4.1. Reference Clock Pins x
4.1.1. QSF Assignments for Reference Clock Pins 4.1.2. Dynamic Reconfiguration of Reference Clock
4.2. Core Clock Network Use Case x
4.2.1. Single 25 Gbps PMA Direct Channel (with FEC) Within a Single FEC Block 4.2.2. Single 10 Gbps PMA Direct Channel (without FEC) 4.2.3. Four 25 Gbps PMA Direct Channel (with FEC) within a Single FEC Block 4.2.4. PMA Direct 25 Gbps x 4 (FEC Off) 4.2.5. PMA Direct 10.3125 Gbps x 4 4.2.6. PMA Direct 100GE Gbps (25 Gbps x 4) (FEC On) 4.2.7. PMA Direct 100GE PAM4 (50 Gbps x 2) (Aggregate FEC On) 4.2.8. PMA Direct High Data Rate (FEC Off)
4.2.3. Four 25 Gbps PMA Direct Channel (with FEC) within a Single FEC Block x
4.2.3.1. Master-Slave Configuration: Option 1 4.2.3.2. Master-Slave Configuration: Option 2
5. PMA Calibration x
5.1. PMA Calibration Revision History
6. Resetting Transceiver Channels x
6.1. When Is Reset Required? 6.2. How Do I Reset? 6.3. Reset Block Architecture 6.4. PMA Analog Reset 6.5. High Level Specification 6.6. Master-Slave Clocking Option 2 Reset Details 6.7. Quartus® Prime Instantiated Transceiver Reset Sequencer 6.8. Block Diagrams 6.9. Interfaces 6.10. Resetting Transceiver Channels Revision History
6.2. How Do I Reset? x
6.2.1. Disabling the E-Tile Transceiver 6.2.2. Selecting the Reset Controller's Clock Source
6.5. High Level Specification x
6.5.1. Automatic Reset Mode 6.5.2. Manual Reset Mode 6.5.3. Reset Controller Bypass
6.5.3. Reset Controller Bypass x
6.5.3.1. Reset Controller Bypass Ports 6.5.3.2. Reset Controller Bypass Reset Procedure
6.9. Interfaces x
6.9.1. Reset Parameters in the Native PHY GUI 6.9.2. HDL Ports/Interfaces
7. Dynamic Reconfiguration x
7.1. Dynamically Reconfiguring Channel Blocks 7.2. Dynamic Reconfiguration Maximum Data Rate Switch 7.3. Interacting with the Dynamic Reconfiguration Interface 7.4. Unsupported Features 7.5. Reading from the Dynamic Reconfiguration Interface 7.6. Writing to the Dynamic Reconfiguration Interface 7.7. Multiple Reconfiguration Profiles 7.8. Arbitration 7.9. Recommendations for PMA Dynamic Reconfiguration 7.10. Steps to Perform Dynamic Reconfiguration 7.11. PMA Attribute Details 7.12. Dynamic Reconfiguration Flow for Special Cases 7.13. Ports and Parameters 7.14. Embedded Debug Features 7.15. Timing Closure Recommendations 7.16. Transceiver Register Map 7.17. Loading IP Configuration Settings 7.18. Dynamic Reconfiguration Revision History
7.7. Multiple Reconfiguration Profiles x
7.7.1. Reconfiguration Files 7.7.2. Embedded Reconfiguration Streamer
7.7.2. Embedded Reconfiguration Streamer x
7.7.2.1. Register 0x40140 7.7.2.2. Register 0x40141
7.12. Dynamic Reconfiguration Flow for Special Cases x
7.12.1. Switching Reference Clocks 7.12.2. Reconfiguring PMA Settings
7.12.1. Switching Reference Clocks x
7.12.1.1. Switching Between Any Two refclk[0, 1, 2, 3, 4, 5, 6, 7] Reference Clocks or Changing the Reference Clock Frequency on refclk[0, 2, 3, 4, 5, 6, 7, 8] 7.12.1.2. Switching from/to refclk[0, 1, 2, 3, 4, 5, 6, 7] to/from refclk[8] 7.12.1.3. Changing the refclk[1] Reference Clock Frequency
7.14. Embedded Debug Features x
7.14.1. Native PHY Debug Master Endpoint (NPDME) 7.14.2. Optional Dynamic Reconfiguration Logic
7.14.2. Optional Dynamic Reconfiguration Logic x
7.14.2.1. Capability Registers 7.14.2.2. Control and Status Registers
7.17. Loading IP Configuration Settings x
7.17.1. Loading IP Configuration Settings Process 7.17.2. Alternative Method for Setting PMA Attributes
8. Dynamic Reconfiguration Examples x
8.1. Reconfiguring the Duplex PMA Using the Reset Controller in Automatic Mode 8.2. PRBS Usage Model 8.3. PMA Error Injection 8.4. PMA Receiver Equalization Adaptation Usage Model 8.5. User-Defined Pattern Example 8.6. Configuring the Attenuation Value (VOD) 8.7. Configuring the Post Emphasis Value 8.8. Configuring pretap1 Values 8.9. Inverting TX Polarity for the PMA Driver 8.10. Inverting RX Polarity for the PMA Driver 8.11. Configuring a PMA Parameter Tunable by the Adaptive Engine 8.12. Configuring a PMA Parameter Using Native PHY IP 8.13. Enabling Low Power Mode for Multiple Channels 8.14. Initializing an RX 8.15. Resetting the RX Equalization 8.16. Dynamic Reconfiguration Examples Revision History
8.12. Configuring a PMA Parameter Using Native PHY IP x
8.12.1. PMA Bring Up Flow Using Native PHY IP 8.12.2. Native PHY IP GUI Details 8.12.3. Loading a PMA Configuration
9. Register Map x
9.1. PMA Register Map 9.2. PMA Attribute Codes 9.3. PMA Registers 0x200 to 0x203 Usage 9.4. Supported Data Rate Ratios for PMA Attribute Codes 0x0005 and 0x0006 9.5. RS-FEC Registers 9.6. Register Map Revision History
9.1. PMA Register Map x
9.1.1. PMA Capability Registers 9.1.2. PMA Control and Status Registers 9.1.3. PMA Avalon® Memory-Mapped Interface
9.2. PMA Attribute Codes x
9.2.1. 0x0001: PMA Enable/Disable 9.2.2. 0x0002: PMA PRBS Settings 9.2.3. 0x0003: Data Comparison Set Up and Start/Stop 9.2.4. 0x0005: TX Channel Divide By Ratio 9.2.5. 0x0006: RX Channel Divide By Ratio 9.2.6. 0x0008: Internal Serial Loopback and Reverse Parallel Loopback Control 9.2.7. 0x000A: Receiver Tuning Controls 9.2.8. 0x000E: RX Phase Slip 9.2.9. 0x0011: PMA TX/RX Calibration 9.2.10. 0x0013: TX/RX Polarity and Gray Code Encoding 9.2.11. 0x0014: TX/RX Width Mode 9.2.12. 0x0015: TX Equalization 9.2.13. 0x0017: Error Counter Reset 9.2.14. 0x0018: Status/Debug Register 9.2.15. 0x0019: Status/Debug Register Next Write Field 9.2.16. 0x001A: Status/Debug Register Next Read Field 9.2.17. 0x001B: TX Error Injection Signal 9.2.18. 0x001C: Incoming RX Data Capture 9.2.19. 0x001E: Error Count Status 9.2.20. 0x0020: Electrical Idle Detector 9.2.21. 0x002B: RX Termination and TX Driver Tri-state Behavior 9.2.22. 0x0030: PMA Mux Clock Swap 9.2.23. 0x0126: Read Receiver Tuning Parameters 9.2.24. Reading and Writing PMA Analog Parameters Using Attributes
9.2.24. Reading and Writing PMA Analog Parameters Using Attributes x
9.2.24.1. Reading PMA Analog Parameters 9.2.24.2. Updating PMA Analog Parameters 9.2.24.3. Loading Parameters into the Receiver 9.2.24.4. Fixing Parameter Values 9.2.24.5. Reading NRZ/PAM4 Eye Height 9.2.24.6. Enabling and Disabling Electrical Idle Detector Filtering and Reading Electrical Idle Detector Status 9.2.24.7. Initial Adaptation Effort Levels
9.3. PMA Registers 0x200 to 0x203 Usage x
9.3.1. PMA Analog Reset 9.3.2. Set PRBS Mode and Internal Serial Loopback 9.3.3. Use Cases for Opcode START_ADAPTATION 9.3.4. Read the Physical Channel Number 9.3.5. Check the PMA Adaptation Status 9.3.6. Load a PMA Configuration using Opcode LOAD_PMA_CONFIGURATION
9.5. RS-FEC Registers x
9.5.1. rsfec_top_clk_cfg 9.5.2. rsfec_top_tx_cfg 9.5.3. rsfec_top_rx_cfg 9.5.4. tx_aib_dsk_conf 9.5.5. rsfec_core_cfg 9.5.6. rsfec_lane_cfg 9.5.7. tx_aib_dsk_status 9.5.8. rsfec_debug_cfg 9.5.9. rsfec_lane_tx_stat 9.5.10. rsfec_lane_tx_hold 9.5.11. rsfec_lane_tx_inten 9.5.12. rsfec_lane_rx_stat 9.5.13. rsfec_lane_rx_hold 9.5.14. rsfec_lane_rx_inten 9.5.15. rsfec_lanes_rx_stat 9.5.16. rsfec_lanes_rx_hold 9.5.17. rsfec_lanes_rx_inten 9.5.18. rsfec_ln_mapping_rx 9.5.19. rsfec_ln_skew_rx 9.5.20. rsfec_cw_pos_rx 9.5.21. rsfec_core_ecc_hold 9.5.22. rsfec_err_inj_tx 9.5.23. rsfec_err_val_tx 9.5.24. rsfec_corr_cw_cnt (Low) 9.5.25. rsfec_corr_cw_cnt (High) 9.5.26. rsfec_uncorr_cw_cnt (Low) 9.5.27. rsfec_uncorr_cw_cnt (High) 9.5.28. rsfec_corr_syms_cnt (Low) 9.5.29. rsfec_corr_syms_cnt (High) 9.5.30. rsfec_corr_0s_cnt (Low) 9.5.31. rsfec_corr_0s_cnt (High) 9.5.32. rsfec_corr_1s_cnt (Low) 9.5.33. rsfec_corr_1s_cnt (High)
10. Debugging E-Tile Transceiver Links x
10.1. E-Tile Transceiver Toolkit Overview 10.2. E-Tile Transceiver Debugging Flow Walkthrough 10.3. Modifying the Design to Enable E-Tile Transceiver Debug 10.4. Programming the Design into an Intel FPGA 10.5. Loading the Design in the E-Tile Transceiver Toolkit 10.6. Verifying E-Tile Hardware Connections 10.7. Running Transceiver Tests 10.8. Controlling PMA Analog Settings 10.9. Debugging E-Tile Transceiver Links Revision History
10.3. Modifying the Design to Enable E-Tile Transceiver Debug x
10.3.1. Debug Parameters for the E-Tile Transceiver IP in the Parameter Editor 10.3.2. Debug Parameters for Stratix® 10 E-Tile Transceiver Native PHY IP in the Parameter Editor 10.3.3. Instantiating and Parameterizing E-Tile Transceiver IP
10.7. Running Transceiver Tests x
10.7.1. Running BER Tests 10.7.2. Link Optimization Tests 10.7.3. Running Eye Viewer Tests
A. E-Tile Channel Placement Tool x
A.1. E-Tile Channel Placement Tool Revision History
B. PMA Direct PAM4 30 Gbps to 57.8 Gbps Implementation x
B.1. Building Blocks and Considerations B.2. Starting a New Quartus® Prime Pro Edition Design B.3. Selecting the Configuration Clock Source B.4. Instantiating the Transceiver Native PHY IP B.5. Instantiating the In-system Sources and Probes Intel® FPGA IP B.6. Making the Top Level Connection B.7. Assigning Pins B.8. Bringing up the Board B.9. Debug Tools B.10. PMA Direct PAM4 30 Gbps to 57.8 Gbps Implementation Revision History
B.9. Debug Tools x
B.9.1. Monitoring Transceiver Signals
C. Signal Detect Algorithm x
C.1. Signal Detect Algorithm Revision History
D. Detailed Steps for Reconfiguring from Mission Mode to Channel Protection Mode x
D.1. Detailed Steps for Reconfiguring from Mission Mode to Channel Protection Mode Revision History
E. Detailed Steps for Reconfiguring from Channel Protection Mode to Mission Mode x
E.1. Detailed Steps for Reconfiguring from Channel Protection Mode to Mission Mode Revision History
F. Hold Timing Violation x
F.1. Hold Timing Violation Revision History
1. E-Tile Transceiver PHY Overview
2. Implementing the Transceiver PHY Layer
3. E-Tile Transceiver PHY Architecture
4. Clock Network
5. PMA Calibration
6. Resetting Transceiver Channels
7. Dynamic Reconfiguration
8. Dynamic Reconfiguration Examples
9. Register Map
10. Debugging E-Tile Transceiver Links
A. E-Tile Channel Placement Tool
B. PMA Direct PAM4 30 Gbps to 57.8 Gbps Implementation
C. Signal Detect Algorithm
D. Detailed Steps for Reconfiguring from Mission Mode to Channel Protection Mode
E. Detailed Steps for Reconfiguring from Channel Protection Mode to Mission Mode
F. Hold Timing Violation

3.1.10.1. Unused Transceiver Channels in a Used Tile

For unused channels in a transceiver tile that also includes channels that are used in the design, a single reference clock must be provided for all protected channels in the tile. Therefore, you must ensure that a stable reference clock is available for the protected channels in the tile. This reference clock must be driven into one of the reference clock inputs of the tile. You can select the reference clock input using QSF assignments (see below).

This reference clock must not change dynamically. This is true for both global and instance QSF assignments (see below). In other words, to protect a channel in a used tile, you must specify a stable, not dynamically changing reference clock for the design along with the QSF assignment for each channel, or else Quartus® Prime errors out. The reference clock frequency must be between 125 and 500 MHz.

The reference clock must be either:

  • One of the existing clocks in the design if it is stable and does not change dynamically or
  • An additional, new reference clock

If you choose the additional, new reference clock option, you must add one port per reference clock for each tile in which you want to preserve unused transceiver channels to the top level design file. For example, if you have three tiles in which you want to preserve unused transceiver channels, add three ports in your top-level design and leave these ports unconnected to any internal logic in the design except for QSF purposes (these port names are just examples; you can name the ports anything you want provided that the port names in the top-level design match the port names specified in the QSF assignments): 

input wire refclk_preserve_ch0, refclk_preserve_ch1, refclk_preserve_ch2

Then, use these ports in the QSF assignments as shown below.

To create the transceiver activity needed for preservation on unused channels, specify the following QSF assignments in the Quartus® Prime Settings File (.qsf), and specify the reference clock needed to protect these channels:

  • Make a global assignment (this QSF assignment preserves all unused transceiver channels in all tiles; you must select one reference clock for each tile that has at least one unused channel): 
    set_global_assignment -name PRESERVE_UNUSED_XCVR_CHANNEL ON

#instance assignments for 3 tiles
set_location_assignment <REFCLK_PIN_1> -to <REFCLK_PORT_1>
set_instance_assignment -name HSSI_PARAMETER "refclk_divider_use_as_bti_clock=true" -to <REFCLK_PORT_1>
set_instance_assignment -name HSSI_PARAMETER “refclk_divider_input_freq=<frequency in Hz>" -to <REFCLK_PORT_1>

set_location_assignment <REFCLK_PIN_2> -to <REFCLK_PORT_2>
set_instance_assignment -name HSSI_PARAMETER "refclk_divider_use_as_bti_clock=true" -to <REFCLK_PORT_2>
set_instance_assignment -name HSSI_PARAMETER "refclk_divider_input_freq=<frequency in Hz>" -to <REFCLK_PORT_2> 

set_location_assignment <REFCLK_PIN_3> -to <REFCLK_PORT_3>
set_instance_assignment -name HSSI_PARAMETER "refclk_divider_use_as_bti_clock=true" -to <REFCLK_PORT_3>
set_instance_assignment -name HSSI_PARAMETER "refclk_divider_input_freq=<frequency in Hz>" -to <REFCLK_PORT_3>

    Example messages seen in Quartus® Prime when using this assignment: 

    Info: Global preservation of unused transceiver channels is enabled. All unused transceiver channels will be preserved.
Info: Preserved 136 unused RX channel(s).
Info: Preserved 136 unused TX channel(s).
  • You can also do channel protection with a QSF-based, per-pin assignment:
    set_instance_assignment -name PRESERVE_UNUSED_XCVR_CHANNEL ON -to <CHANNEL_PIN1>
set_instance_assignment -name PRESERVE_UNUSED_XCVR_CHANNEL ON -to <CHANNEL_PIN2>
set_location_assignment <REFCLK_PIN>  -to <REFCLK_PORT> // <REFCLK_PORT> is used for preserve above two specific channels in same tile
set_instance_assignment -name HSSI_PARAMETER "refclk_divider_use_as_bti_clock=TRUE" -to <REFCLK_PORT>
set_instance_assignment -name HSSI_PARAMETER "refclk_divider_input_freq=<frequency in Hz>" -to <REFCLK_PORT>

    Here is an example: 

    set_instance_assignment -name PRESERVE_UNUSED_XCVR_CHANNEL ON -to R51
set_instance_assignment -name PRESERVE_UNUSED_XCVR_CHANNEL ON -to M48
set_location_assignment PIN_AA40  -to refclk_preserve_ch1 // refclk_preserve_ch1 is used for above two channels
set_instance_assignment -name HSSI_PARAMETER "refclk_divider_use_as_bti_clock=TRUE" -to refclk_preserve_ch1
set_instance_assignment -name HSSI_PARAMETER "refclk_divider_input_freq=200000000" -to refclk_preserve_ch1

    Example messages seen in Quartus® Prime when using this QSF assignment: 

    Info: Channel-specific preservation of unused transceiver channels is enabled
Info: Unused transceiver channel at location 'R51' will be preserved
Info: Unused transceiver channel at location 'M48' will be preserved
Info: Unused transceiver channel at location 'BM13' will be preserved
Info: Unused transceiver channel at location 'BP7' will be preserved
Info: Unused transceiver channel at location 'BD7' will be preserved
Info: Preserved 5 unused RX channel(s).
Info: Preserved 5 unused TX channel(s).

The pin name can be either a transmit or receive serial pin of the channel you want to preserve.

Both options give you the following error messages when more than one reference clock is specified in QSF file: 

Error: Two reference clocks (refclk_preserve_ch0, refclk_preserve_ch1) have been specified for preserving unused transceiver channels in HSSI IO BANK 8B.
       Only one reference clock is allowed to be specified using the QSF assignment set_instance_assignment -name HSSI_PARAMETER "refclk_divider_use_as_bti_clock=TRUE" -to inst_name. See E-tile User Guide for more information.

Quartus® Prime gives a critical warning if there are unused transceiver channels in the design if the global or per-pin QSF assignment is not specified: 

Critical Warning (19527): There are xx unused RX channels and yy unused TX channels in the design. 
Add the QSF assignment 'set_instance_assignment -name PRESERVE_UNUSED_XCVR_CHANNEL ON -to <pin_name>' for each unused channel you want to preserve.
The above QSF assignment preserves the performance of specified channels over time.
Level Two Title