Common Management Interface Specification - QSFP-DD

1 Published Rev Common Management Interface Specification Page 1 Common Management Interface Specification Rev May 8, 2019 Abstract: This document defines the Common Management Interface Specification (CMIS) that may be used by pluggable modules with host to module Management communication based on a Two-Wire- Interface (TWI), such as qsfp Double Density ( QSFP-DD ), OSFP, COBO, qsfp , and SFP-DD. This document provides a Common Specification for systems manufacturers, system integrators, and suppliers of modules and transceivers.

2 POINTS OF CONTACT: Tom Palkert Mark Nowell Scott Sommers Technical Editor Co-Chair Co-Chair Molex Cisco Molex 2222 Wellington Court 170 West Tasman Dr 2222 Wellington Court Lisle, IL 60532-1682 San Jose, CA 95134 Lisle, IL 60532-1682 Ph: +1 (952)-200-8542 Ph: +1 (613)-254-3391 Ph: +1 (630)-527-4317 at mnowell at at Limitation on use of Information: This Specification is provided "AS IS" with NO WARRANTIES whatsoever and therefore the provision of this Specification does not include any warranty of merchantability, noninfringement, fitness for a particular purpose, or any other warranty otherwise arising out of any proposal, Specification or sample.

3 The authors further disclaim all liability, including liability for infringement of any proprietary rights, relating to use of information in this Specification . No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted herein. Permissions: You are authorized to download, reproduce and distribute this document. All other rights are reserved. The provision of this document should not be construed as the granting of any right to practice, make, use or otherwise develop products that are based on the document.

4 Any and all IP rights related to this document and the designs disclosed within, except for the rights expressly mentioned above, are reserved by the respective owners of those IP rights. Published Rev Common Management Interface Specification Page 2 Foreword The development work on this Specification was done by the QSFP-DD , OSFP and COBO advisory group. Further revisions of the CMIS shall be backwards compatible to implementations conforming to Revision Revision History Rev August 17, 2018: - Initial public release Draft Rev January 7, 2019.

5 - Converted InitMode signal to continuously-sampled LPMode - Associated Module and Data Path State Machine changes - Added LPMode Override bit - Added pages 04h and 12h for tunable laser support - Added diagnostic pages 13h and 14h - New format to conform to SFF - Added Command Data Block (CDB) section (pages 9Fh and A0h-AFh) Draft Rev May 8, 2019: WARNING: Implementations compliant to CMIS Revision of this Specification will not interoperate with revision implementations and vice-versa.

6 The following specifications have changed: - Converted InitMode signal to continuously-sampled LPMode - Data Path initialization control (Page 10h) meaning/polarity has changed - Added LowPwr register (Lower memory, Byte 26, bit 6) to switch power mode Other changes: - Added Scope statement - Added Conventions - Added Definitions - Updated Introduction - Consolidation of section 5 - Rework and Partial Consolidation of section 6 - Added Versatile Digital Diagnostics Monitoring ( ) - Added CDB Feature ( and 9) - Moved Examples to Appendix - Change Upper Page Lower Page terminology (Upper and Lower Memory plus Pages)

7 - Removed Interface ID tables and replaced them with references to SFF-8024 Published Rev Common Management Interface Specification Page 3 Contents 1 Scope and Purpose 13 2 References and Conventions 14 Industry Documents 14 Sources 14 Conventions 14 3 Keywords, Acronyms, and Definitions 16 Keywords 16 Acronyms and Abbreviations 16 Definitions 17 4 Introduction and General Description 20 CMIS Compliant Modules 20 Management Protocol Layers 20 5 Management Interface 21 Management Control Signals 21 Management Communication Interface 21 General Description 21 Physical Layer 21 Serial Communication Protocol 22 Basic Definitions 22 Start Condition (START) 22 Stop Condition (STOP) 22 Word Size (Byte) 22 Basic Operation Encoding (Control Byte)

8 22 Acknowledge (ACK) 22 Clock Stretching 22 Acknowledge Polling 22 Protocol Reset and Recovery 23 Power On Reset 23 Protocol Reset and Recovery 23 Binary Serial Frame Format for Basic Operations 23 Read/Write Control Byte and Response 23 Byte Address and Data 23 Read/Write Operations 24 Slave Memory Current Byte Address Counter (Read and Write Operations) 24 Data Coherency 24 Byte Read Operations 25 Current Address Read Operation 25 Random Read Operation 26 Sequential Bytes Read Operation 27 Sequential Read from Current Start Address 27 Sequential Read from Random Start Address 28 Byte Write Operation 29 Sequential Bytes Write Operation 30 Timing Specifications 31 6 Core Management Features 32 Module Management Basics 32 Host Interface Conventions 32 Media Interface Conventions 32 Interface Memory Map Representations 32 Module

9 Functional Model 33 Published Rev Common Management Interface Specification Page 4 Functional Module Capabilities Applications 33 Advertising Methodology 34 Logical Module Use Data Paths 36 Data Path Configuration Control Sets 36 Control Set Usage 37 Initialization Sequence Examples 38 Signal Integrity Controls 39 Tx Input Equalization Control 39 Rx Output Emphasis Control 40 Rx Output Amplitude Control 40 Tx Input Eq Adaptation Store/Recall Methodology 40 Module Behavioral Model 42 Module State Machine 42 Module State Machine, paged memory modules 42 Module State Machine.

10 Flat memory modules 47 Module Power Mode control 48 Resetting State 48 Reset State 49 MgmtInit State 49 ModuleLowPwr State 50 ModulePwrUp state 50 ModuleReady State 50 ModulePwrDn State 51 Fault State 51 Data Path State Machine 51 Data Path control and status 56 DataPathDeactivated State 57 DataPathInit State 57 DataPathInitialized State 58 DataPathDeinit State 58 DataPathTxTurnOn State 59 DataPathActivated State 60 DataPathTxTurnOff State 60 Interrupt Flag Conformance per State 61 Module Flag Conformance per State 61 Lane-Specific Flag Conformance per State 62 7 Advanced Management Features 64 Versatile Diagnostics Monitoring (VDM) 64 Overview 64 PAM4 Monitored Parameters 65 SNR 66 PAM Level Transition Parameter 66 Error Metrics 67 DWDM Monitored Parameters 68 TEC Current 68 Laser Frequency 68 Laser Temperature 68 Command Data Block (CDB) Message Communication 69 CDB support levels 69 Sequential CDB (foreground only)