Architected Protocol For Changing Link Operating Mode

摘要

In one embodiment, a device having a link training state machine including a reconfiguration logic to perform a dynamic link reconfiguration of a physical link coupled between the device and a second device during a run-time in which the physical link does not enter a link down state, including transmission of a plurality of bandwidth change requests to the second device, each of the plurality of bandwidth change requests to request a bandwidth change from a first bandwidth to a second bandwidth. Other embodiments are described and claimed.

主权项

1. An apparatus comprising:
a logic to operate a Peripheral Component Interconnect Express™ (PCIe™) based transaction layer and a link layer; and a physical unit coupled to the logic to transmit and receive data via a physical link, wherein the apparatus comprises a downstream device and a device coupled to the apparatus via the physical link comprises an upstream device, the physical unit including a M-PHY electrical layer and a logical layer to interface the logic with the M-PHY electrical layer, the logical layer including a link training and status state machine (LTSSM) configured to manage the physical link, wherein the downstream device is to initiate a re-configuration of the physical link and to:
transmit a plurality of first training set messages to the device, each of the plurality of first training set messages including a link bandwidth change indicator having a first state to indicate that a bandwidth change is requested;receive a second plurality of first training set messages from the device, each of the second plurality of first training set messages including the link bandwidth change indicator having the first state;transmit a plurality of second training set messages to the device, each of the plurality of second training set messages including a link bandwidth change indicator having the first state; andreceive a plurality of second training set messages from the device, each of the plurality of second training set messages including a link bandwidth change confirmation indicator having a second state to indicate that the bandwidth change is acknowledged.