Intel Corporation

Hewlett-packard Development Company, L.p.

Hewlett-packard Company

Debendra Das Sharma

Robert G Blankenship

Mahesh U Wagh

Michelle C Jen

David J Harriman

Ilan Pardo

Ajay V Bhatt

Venkatraman Iyer

Zuoguo Wu

Anil Vasudevan

Sridhar Muthrasanallur

Mark B Rosenbluth

Jasmin Ajanovic

Scott Dion Rodgers

Prashant Sethi

James E Akiyama

Eran Tamari

Doron Shamia

Peter J Barry

Eliezer Weissmann

Ohad Falik

Robert J Safranek

Fulvio Spagna

Swadesh Choudhary

Daniel S Froelich

Darren S Jue

Jeffrey Charles Swanson

Bruce A Tennant

Mohan J Kumar

Gerald S Pasdast

Ashish Gupta

Balint Fleischer

Raj K Ramanujan

Abraham Mendelson

Rahul R Shah

Arvind A Kumar

Yen-Cheng Liu

Simon P Johnson

Herbert H Hum

Vedaraman Geetha

Bahaa Fahim

Brian S Morris

Aaron T Spink

Jeff Willey

Robert H Beers

Jeff C Morriss

Sitaraman V Iyer

William Harry Nale

Mohiuddin M Mazumder

Lakshmipriya Seshan

Abhishek Das

Yuvraj S Dhillon

Robert A Maddox

Prahladachar Jayaprakash Bharadwaj

Avi Mendelson

Akshay G Pethe

Narasimha R Lanka

John Alan Wickeraad

Dror Reif

Gurushankar Rajamani

Ido Y Soffair

Narasimha Lanka

Hanh Hoang

Mark A Schmisseur

Kai Xiao

Su Wei Lim

Alexander Barraclough Brown

Sean O Stalley

Sharon M Ebner

Junaid Thaliyil

Md Mohiuddin Mazumder

Stephen R Van Doren

Kenneth C Creta

Ramacharan Sundararaman

Timothy D Wig

Mark S Myers

Jong-Ru Guo

Joe Perry Cowan

Anil Rao

Don Soltis

Edward M Jacobs

Donald A Williamson

Adel A Elsherbini

David Stewart Dunning

Mahesh S Natu

Ganapati Srinivasa

William R Bryg

Joseph Murray

Abhishek Singhal

Annie Foong

Suresh S Chittor

Kent Andrew Dickey

Tao Liang

Eric R Wehage

Keith A Drescher

Richard J Glass

Ramasubramanian Rajamani

Chandra P Joshi

Eric M Lee

In one embodiment, an apparatus includes: a die-to-die adapter to communicate with a protocol layer and physical layer circuitry, and the physical layer circuitry coupled to the die-to-die adapter, where the physical layer circuitry is to receive and output first information to a second die via an interconnect. The physical layer circuitry, after a reset flow for the first die, is to: perform a sideband initialization of a sideband interface of the interconnect to detect that the second die has completed a reset flow for the second die; and after the sideband initialization, perform a mainband initialization of a mainband interface of the interconnect at a lowest speed, and thereafter perform a mainband training of the mainband interface at a negotiated data rate. Other embodiments are described and claimed.

Link initialization training and bring up for die-to-die interconnect

A first die has a port to couple the first die to a second die over a die-to-die interconnect. The port includes circuitry to implement a physical layer of the die-to-die interconnect, send first protocol identification data over the physical layer to identify a first protocol in a plurality of protocols, send first data over the interconnect to the second die, wherein the first data comprise data of the first protocol, send second protocol identification data over the physical layer to identify a different second protocol in the plurality of protocols, and send second data over the interconnect to the second die, wherein the second data comprise flits of the second protocol.

Sharing memory and I/O services between nodes

A shared memory controller receives a flit from another first shared memory controller over a shared memory link, where the flit includes a node identifier (ID) field and an address of a particular line of the shared memory. The node ID field identifies that the first shared memory controller corresponds to a source of the flit. Further, a second shared memory controller is determined from at least the address field of the flit, where the second shared memory controller is connected to a memory element corresponding to the particular line. The flit is forwarded to the second shared memory controller using a shared memory link according to a routing path.

Shared buffered memory routing

An interconnect interface is provided to enable communication with an off-package device over a link including a plurality of lanes. Logic of the interconnect interface includes receiver logic to receive a valid signal from the off-package device on a dedicated valid lane of the link indicating that data is to arrive on a plurality of dedicated data lanes in the plurality of lanes, receive the data on the data lanes from the off-package device sampled based on arrival of the valid signal, and receive a stream signal from the off-package device on a dedicated stream lane in the plurality of lanes. The stream signal corresponds to the data and indicates a particular data type of the data. The particular data type can be one of a plurality of different data types capable of being received on the plurality of data lanes of the link.

Extending multichip package link off package

In an embodiment, an apparatus includes a receiver circuit to: in response to a determination that the receiver circuit is in a high latency processing mode, transmit a hint signal to a transmitter circuit; receive a response message from the transmitter circuit; process the response message to reduce a current workload of the receiver circuit; and switch the receiver circuit from the high latency processing mode to a low latency processing mode. Other embodiments are described and claimed.

Selection of processing mode for receiver circuit

Embodiments herein relate to action that are to be taken on various lanes of a die-to-die (D2D) interconnect in the event of clock-gating. Specifically, based on identification that a clock-gating event is to occur, physical layer (PHY) logic may direct PHY electrical circuitry to set the state of various of the lanes. In some embodiments, different actions may be taken based on whether the D2D interconnect is terminated or unterminated. Other embodiments may be described and claimed.

Clock-gating in die-to-die (D2D) interconnects

A port is to couple to another die over a die-to-die (D2D) link and includes a die-to-die (D2D) adapter to determine, from a set of registers, a set of capabilities of the D2D adapter to advertise in a negotiation with a link partner D2D adapter, where the D2D adapter is on a die and the link partner D2D adapter is located on a remote link partner die. A first capabilities advertisement message is sent to the link partner D2D adapter to advertise the set of capabilities to the link partner D2D adapter. A second capabilities advertisement message is received from the link partner D2D adapter, wherein the second capabilities advertisement message identifies a set of capabilities of the link partner D2D adapter. A final configuration of a D2D link is determined to couple the die to the link partner die.

Parameter exchange for a die-to-die interconnect

In one embodiment, an apparatus comprises a first die that includes: a die-to-die adapter comprising a plurality of first registers, the die-to-die adapter to communicate with protocol layer circuitry via a flit-aware die-to-die interface (FDI) and physical layer circuitry via a raw die-to-die interface (RDI), wherein the die-to-die adapter is to receive message information of a first interconnect protocol; and the physical layer circuitry coupled to the die-to-die adapter, the physical layer circuity comprising a plurality of second registers, where the physical layer circuitry is to receive and output the message information to a second die via an interconnect having a mainband and a sideband. During a test of the apparatus, the sideband is to enable access to information in at least one of the plurality of first registers or at least one of the plurality of second registers. Other embodiments are described and claimed.

Compliance and debug testing of a die-to-die interconnect

Systems and devices can include a port for transmitting data; and a link coupled to the port. The port, in preparation to transmit a data block across the link, to determine a size of a burst of data to be transmitted across the link; determine a plurality of error correcting code words for forward error correction based on the size of the burst of data; interleave each of the plurality of error correcting code words to correspond with consecutive symbols of the burst of data; and transmit the burst of data comprising the interleaved plurality of error correcting code across the link.

Low-latency forward error correction for high-speed serial links

In an embodiment, a system may include an interconnect device comprising first, second, and third ports; a first processor coupled to the first port; a second processor coupled to the second port; and a system memory coupled to the third port. The interconnect device may be to: receive, from the first processor via the first port, a speculative read request for a data element stored in the system memory, where coherence of the data element is managed by the second processor, receive a direct read request for the data element, merge the direct read request with the speculative read request, and transmit the data element directly to the first processor via the first port. Other embodiments are described and claimed.

System, apparatus and methods for direct data reads from memory

A port is to couple to another die over a die-to-die (D2D) link and includes physical layer (PHY) circuitry including a first number of sideband lanes to carry data for use in training and management of the D2D link, and a second number of mainband lanes to implement a main data path of the D2D link. The mainband lanes include a forwarded clock lane, a valid lane, and a plurality of data lanes. A logical PHY coordinates functions of the sideband lanes and the mainband lanes.

Die-to-die interconnect

A device includes a port with a replay buffer and protocol logic to receive a flit in a sequence of flits to be sent on a point-to-point link and determine an error in the flit. Based on the error, a copy of the flit is stored in a first position within the replay buffer as well as a copy of a next flit received in the sequence of flits, which is stored in a second position within the replay buffer. The copies of the flits are then written to a register for access by software.

Hardware logging for lane margining and characterization

In one embodiment, an apparatus includes: a die-to-die adapter to communicate with protocol layer circuitry and physical layer circuitry; and the physical layer circuitry coupled to the die-to-die adapter, where the physical layer circuitry is to receive and output first information to a second die via an interconnect. The physical layer circuitry may include: a first sideband data receiver to couple to a first sideband data lane and a first sideband clock receiver to couple to a first sideband clock lane; and a second sideband data receiver to couple to a second sideband data lane and a second sideband clock receiver to couple to a second sideband clock lane. The physical layer circuitry may assign a functional sideband comprising: one of the first or second sideband data lanes; and one of the first or second sideband clock lanes. Other embodiments are described and claimed.

Sideband interface for die-to-die interconnects

A first flit is generated according to a first flit format, where a first number of error detection codes are to be provided for an amount of data to be sent in the first flit, and the first flit is to be sent on a link by the transmitter while the link operates with a first link width. The link transitions from a first link width to a second link width, where the second link width is narrower than the first link width. A second flit is generated according to a second flit format based on the transition to the second link width, where the second flit is to be sent while the link operates at the second link width, and the second flit format defines that a second, higher number of error detection codes are to be provided for the same amount of data.

Latency optimization in partial width link states

In one embodiment, an apparatus includes PHY circuitry to implement a PHY-based retry technique, e.g., in die-to-die interfaces. The PHY circuitry includes a retry buffer to buffer data provided by the interface controller and error detection code generation circuitry to generate error detection codes based on input data. The PHY circuitry is to implement the retry technique by detecting a stall signal asserted by another apparatus across the channel, causing the error detection code generation circuitry to generate error detection codes based on data in the retry buffer, and transmitting the data from the retry buffer and its corresponding error detection codes across the channel to the other apparatus.

PHY-based retry techniques for die-to-die interfaces

Growing community of inventors

Saratoga, CA, United States of America

Debendra Das Sharma