Abstract: Systems and methods of managing a link provide for receiving a remote width capability during a link initialization, the remote width capability corresponding to a remote port. A link between a local port and the remote port is operated at a plurality of link widths in accordance with the remote width capability.

Abstract: In some embodiments, a chip comprises control circuitry to provide inband signals, inband output ports, and transmitters to transmit the inband signals to the inband output ports. The control circuitry selectively includes loopback initiating commands in the inband signals. Other embodiments are described and claimed.

Abstract: REUT (Robust Electrical Unified Testing) for memory links is introduced which speeds testing, tool development, and debug. In addition it provides training hooks that have enough performance to be used by BIOS to train parameters and conditions that have not been possible with past implementations. Address pattern generation circuitry is also disclosed.

Abstract: A predetermined network packet is utilized for power reduction in either or both of a transmitter and receiver when information is not needed. Upon detection of the predetermined network packet type, various portions of the transmitter and/or receiver may be clock gated or powered down.

Abstract: Embodiments of the invention provide an algorithm for dividing a link into one or more reduced-width links. For one embodiment of the invention, a multiplexing scheme is employed to effect a bit transmission order required by a particular cyclic redundancy check. The multiplexed output bits are then swizzled on-chip to reduce on-board routing congestion.

Abstract: In some embodiments, a chip comprises control circuitry to provide inband signals, inband output ports, and transmitters to transmit the inband signals to the inband output ports. The control circuitry selectively includes loopback initiating commands in the inband signals. Other embodiments are described and claimed.

Abstract: Methods and apparatus relating to link power savings with state retention are described. In one embodiment, one or more components of two agents coupled via a serial link are turned off during idle periods while retaining link state in each agent. Other embodiments are also disclosed.

Abstract: A technique is described by which two link agents with ports coupled together using a point-to-point interconnect in a system exchange their link width support capabilities and negotiate a link width that is mutually agreeable. The interconnect between each pair of agents comprises a pair of uni-directional links having multiple electrical wires, or lanes, where one link is used by a first agent to transmit data to a second agent and another link is used by the second agent to transmit data to the first agent.

Abstract: Embodiments of the invention are generally directed to systems, methods, and apparatuses for the active training of memory command timing. In some embodiments, the CMD/CTL timing is actively trained using active feedback between memory modules and the memory controller. Other embodiments are described and claimed.

Abstract: A discussion of improving integrated device deterministic response to test vectors. For example, limiting the transmission delay for an integrated device's response within known bounds by synchronizing an initialization training sequence to a reset deassertion. Specifically, the proposal facilitates response determinism from the DUT by synchronizing training sequences and subsequently synchronizing flit transmission to reset assertion as sampled by reference clock.

Abstract: A loopback test to test a communication link for a layered interface where in a master agent programs the electrical parameters for the slave agent, such as, the offset, timing, and current compensation with a loopback control register.

Abstract: A technique for promoting determinism among bus agents within a point-to-point (PtP) network. More particularly, embodiments of the invention relate to techniques to compensate for link latency, data skew, and clock shift within a PtP network of common system interface (CSI) bus agents.

Abstract: A method and apparatus for advancing initialization messages when initializing an interface is presented. In one embodiment, one of a sequence of training sequence messages are sent in serial mode across the data lanes of a generally-parallel interface between two agents. When one agent correctly receives a fixed number of messages, it may begin sending its messages with an acknowledgement. Thereafter, when that agent correctly receives a fixed number of messages including an acknowledgement, that agent may advance to sending the next training sequence messages in the sequence.

Abstract: A predetermined network packet is utilized for power reduction in either or both of a transmitter and receiver when information is not needed. Upon detection of the predetermined network packet type, various portions of the transmitter and/or receiver may be clock gated or powered down.

Abstract: Disclosed are embodiments of a method, apparatus and system for a low power state for a point-to-point link. During the low power state, the signal on both conductors of a differential transmit pair are driven to electrical idle. Analog activity detectors are enabled during the low power state and are disabled during normal power state. Exit from the low power state does not require a physical layer re-initialization sequence. Other embodiments are also described and claimed.

Abstract: A predetermined network packet is utilized for power reduction in either or both of a transmitter and receiver when information is not needed. Upon detection of the predetermined network packet type, various portions of the transmitter and/or receiver may be clock gated or powered down.

Abstract: According to one embodiment, a built-in self test (IBIST) architecture/methodology is disclosed. The IBIST provides for testing the functionality of an interconnect (such as a bus) between a transmitter and a receiver component. The IBIST architecture includes a pattern generator and a pattern checker. The pattern checker operates to compare a received plurality of bits (for the pattern generator) with a previously stored plurality of bits.

Abstract: A serial point to point link that communicatively couples an integrated circuit (IC) device to another IC device is initialized by transferring a training sequence of symbols over the link. Registers of the IC device are programmed, to set a symbol data pattern and configure a lane transmitter for the link. A start bit in a register of the IC device is programmed, to request that the link be placed in a measurement mode. In this mode, the IC device instructs the other IC device to enter a loopback mode for the link. The IC device transmits a sequence of test symbols over the link and evaluates a loopback version of the sequence for errors. The sequence of test symbols have a data pattern, and are transmitted, as configured by the registers. Other embodiments are also described and claimed.

Abstract: In some embodiments, a chip includes first and second nodes, a variable voltage source, and transmitter and control circuitry. The transmitter includes a driver coupled to the first and second nodes, and first and second resistive structures coupled between the first and second nodes, respectively, and the variable voltage source. The control circuitry selects an impedance level for the first and second resistive structures, and detect coupling of a remote receiver to the transmitter through interconnects and detect decoupling of the remote receiver from the transmitter. Other embodiments are described and claimed.

Abstract: A loopback test to test a communication link for a layered interface where in a master agent programs the electrical parameters for the slave agent, such as, the offset, timing, and current compensation with a loopback control register. The slave and master agent to support an entry into the loopback test based on detection of a header within a packet. The slave and master agent to support exit out of the loopback test based on whether the loop count is finite.