Abstract: A physical layer (PHY) is coupled to a serial, differential link that is to include a number of lanes. The PHY includes a transmitter and a receiver to be coupled to each lane of the number of lanes. The transmitter coupled to each lane is configured to embed a clock with data to be transmitted over the lane, and the PHY periodically issues a blocking link state (BLS) request to cause an agent to enter a BLS to hold off link layer flit transmission for a duration.

Abstract: Methods, apparatus, and systems, for transporting data units comprising multiple pieces of transaction data over high-speed interconnects. A flow control unit, called a KTI (Keizer Technology Interface) Flit, is implemented in a coherent multi-layer protocol supporting coherent memory transactions. The KTI Flit has a basic format that supports use of configurable fields to implement KTI Flits with specific formats that may be used for corresponding transactions. In one aspect, the KTI Flit may be formatted as multiple slots used to support transfer of multiple respective pieces of transaction data in a single Flit. The KTI Flit can also be configured to support various types of transactions and multiple KTI Flits may be combined into packets to support transfer of data such as cache line transfers.

Abstract: A request is received over a link that requests a particular line in memory. A directory state record is identified in memory that identifies a directory state of the particular line. A type of the request is identified from the request. It is determined that the directory state of the particular line is to change from the particular state to a new state based on the directory state of the particular line and the type of the request. The directory state record is changed, in response to receipt of the request, to reflect the new state.

Abstract: Re-initialization of a link can take place without termination of the link, where the link includes, a transmitter and a receiver are to be coupled to each lane in the number of lanes, and re-initialization of the link is to include transmission of a pre-defined sequence on each of the lanes.

Abstract: In an embodiment, a processor includes a plurality of cores and synchronization logic. The synchronization logic includes circuitry to: receive a first memory request and a second memory request; determine whether the second memory request is in contention with the first memory request; and in response to a determination that the second memory request is in contention with the first memory request, process the second memory request using a non-blocking cache coherence protocol. Other embodiments are described and claimed.

Abstract: A supersequence corresponding to an initialization state is received on a link that includes a repeating pattern of an electrical idle exit ordered set (EIEOS) followed by a number of consecutive training sequences. Instances of the EIEOS are to be aligned with a rollover of a sync counter. A latency value is determined from one of the EIEOS instances in the supersequence and latency is added to a receive path of the link through a latency buffer based on the latency value.

Abstract: Re-initialization of a link can take place without termination of the link, where the link includes, a transmitter and a receiver are to be coupled to each lane in the number of lanes, and re-initialization of the link is to include transmission of a pre-defined sequence on each of the lanes.

Abstract: Transaction data is identified and a flit is generated to include three or more slots and a floating field to be used as an extension of any one of two or more of the slots. In another aspect, the flit is to include two or more slots, a payload, and a cyclic redundancy check (CRC) field to be encoded with a 16-bit CRC value generated based on the payload. The flit is sent over a serial data link to a device for processing, based at least in part on the three or more slots.

Abstract: Transaction data is identified and a flit is generated to include three or more slots and a floating field to be used as an extension of any one of two or more of the slots. In another aspect, the flit is to include two or more slots, a payload, and a cyclic redundancy check (CRC) field to be encoded with a 16-bit CRC value generated based on the payload. The flit is sent over a serial data link to a device for processing, based at least in part on the three or more slots.

Abstract: Data is sent from a memory buffer device to a host device over a link. An error in the data is determined. A read response cancellation signal is sent to the host device to indicate the error to the host device, where the read response cancellation signal is to be sent subsequent to the data being sent from the memory buffer device to the host device.

Abstract: Examples may include techniques to enable cache coherency of objects in a distributed shared memory (DSM) system, even where multiple nodes in the system manage the objects. Node memory space includes a tracking address space (TAS) where lines in the TAS correspond to objects in the (DSM). Access to the objects and the TAS is managed by a host fabric interface (HFI) caching agent in HFI of a node.

Abstract: Embodiment of this disclosure provides a mechanism to use a portion of an inactive processing element's private cache as an extended last-level cache storage space to adaptively adjust the size of shared cache. In one embodiment, a processing device is provided. The processing device comprising a cache controller is to identify a cache line to evict from a shared cache. An inactive processing core is selected by the cache controller from a plurality of processing cores associated with the shared cache. Then, a private cache of the inactive processing core is notified of an identifier of a cache line associated with the shared cache. Thereupon, the cache line is evicted from the shared cache to install in the private cache.

Abstract: Methods, apparatus, and systems, for transporting data units comprising multiple pieces of transaction data over high-speed interconnects. A flow control unit, called a KTI (Keizer Technology Interface) Flit, is implemented in a coherent multi-layer protocol supporting coherent memory transactions. The KTI Flit has a basic format that supports use of configurable fields to implement KTI Flits with specific formats that may be used for corresponding transactions. In one aspect, the KTI Flit may be formatted as multiple slots used to support transfer of multiple respective pieces of transaction data in a single Flit. The KTI Flit can also be configured to support various types of transactions and multiple KTI Flits may be combined into packets to support transfer of data such as cache line transfers.

Abstract: Methods, apparatus, and systems for reliable replication mechanisms based on active-passive HFI protocols build on top of non-reliable multicast fabric implementations. Under a first hardware-based scheme, a reliable replication mechanism is (primarily) implemented via Host Fabric Interfaces (HFIs) coupled to (or integrated in) nodes coupled to a non-reliable fabric. Under this approach, the HFIs take an active role in ensuring reliable delivery of multicast messages to each of multiple target nodes. Under a second hybrid software/hardware scheme, software running on nodes is responsible for determining whether target nodes have confirmed delivery of multicast messages and sending retry messages for cases in which delivery is not acknowledged within a timeout period. At the same time, the HFIs on the target nodes are responsible for generating reply messages containing acknowledgements rather than software running on the target nodes.

Abstract: An apparatus and method for multi-level cache request tracking.

Abstract: A coherence protocol message is sent corresponding to a particular cache line. A potential conflict involving the particular cache line is identified and a forward request is sent to a home agent to identify the potential conflict. A forward response can be received in response to the forward request from the home agent and a response to the conflict can be determined.

Abstract: An apparatus and method for multi-level cache request tracking.

Abstract: A method for adaptively performing a set of data transfer processes in a multi-core processor is described. The method may include receiving, by a shared cache from a first core cache, a first request for a cache line; determining, by the shared cache in response to receipt of the first request, whether the cache line is a widely-shared cache line or a single-producer-single-consumer cache line; and performing, by the first core cache and a second core cache, a three-hop data transfer process in response to determining that the cache line is a single-producer-single-consumer cache line, wherein the three-hop data transfer process transfers the cache line directly from the second core cache to the first core cache.

Abstract: Memory is to store cache lines, where the cache lines include data and directory information to indicate a directory state of the corresponding cache line. A command is received from a processor over a link, the command including an address. The address is determined to correspond to a particular cache line and the particular cache line is identified to have a particular directory state from the corresponding directory information of the particular cache line. A type of the command is identified and a determination is made that that the directory state of the particular cache line is to change from the particular state to a new state based on the type of the command. The directory information of the particular cache line is changed to reflect the new state and a response is generated to the command.

Abstract: A physical layer (PHY) is coupled to a serial, differential link that is to include a number of lanes. The PHY includes a transmitter and a receiver to be coupled to each lane of the number of lanes. The transmitter coupled to each lane is configured to embed a clock with data to be transmitted over the lane, and the PHY periodically issues a blocking link state (BLS) request to cause an agent to enter a BLS to hold off link layer flit transmission for a duration. The PHY utilizes the serial, differential link during the duration for a PHY associated task selected from a group including an in-band reset, an entry into low power state, and an entry into partial width state.