Abstract: Safe handling of link errors in a Peripheral Component Interconnect (PCI) express (PCIE) device is disclosed. In one aspect, safe handling of link errors involves detecting errors in a PCIE link and maintaining the PCIE link by preventing the reporting of detected errors and providing safe data to a host in communication with the PCIE link. A PCIE link can be established between a host (incorporating a root complex) and an endpoint device, through which the host can request the performance of operations (e.g., read data, write data) by the endpoint device. Circuitry and/or software can monitor the PCIE link and perform safe handling of link errors when they occur. The circuitry detects link errors and consumes them in such a manner that the host is unaware that an error has occurred and only safe (e.g., non-corrupted) data is provided to the host.

Abstract: Safe handling of link errors in a Peripheral Component Interconnect (PCI) express (PCIE) device is disclosed. In one aspect, safe handling of link errors involves detecting errors in a PCIE link and maintaining the PCIE link by preventing the reporting of detected errors and providing safe data to a host in communication with the PCIE link. A PCIE link can be established between a host (incorporating a root complex) and an endpoint device, through which the host can request the performance of operations (e.g., read data, write data) by the endpoint device. Circuitry and/or software can monitor the PCIE link and perform safe handling of link errors when they occur. The circuitry detects link errors and consumes them in such a manner that the host is unaware that an error has occurred and only safe (e.g., non-corrupted) data is provided to the host.

Abstract: Asymmetric power states on a communication link are disclosed. In one aspect, the communication link is a Peripheral Component Interconnect (PCI) express (PCIe) link. PCIe is a point-to-point communication link between two termini. Exemplary aspects of the present disclosure allow the two termini to be in different power states. By allowing the two termini to be in the different power states, an individual terminus may be put into a low-power state even though the other terminus is maintained at a higher-power state. The different power states are enabled by providing switches between a reference clock and respective termini such that the reference clock may selectively be provided to only one terminus of the communication link, allowing that terminus to remain in the higher-power state while the other terminus enters a low-power state that does not require the reference clock.

Abstract: Asymmetric power states on a communication link are disclosed. In one aspect, the communication link is a Peripheral Component Interconnect (PCI) express (PCIe) link. PCIe is a point-to-point communication link between two termini. Exemplary aspects of the present disclosure allow the two termini to be in different power states. By allowing the two termini to be in the different power states, an individual terminus may be put into a low-power state even though the other terminus is maintained at a higher-power state. The different power states are enabled by providing switches between a reference clock and respective termini such that the reference clock may selectively be provided to only one terminus of the communication link, allowing that terminus to remain in the higher-power state while the other terminus enters a low-power state that does not require the reference clock.

Abstract: Asymmetric power states on a communication link are disclosed. In one aspect, the communication link is a Peripheral Component Interconnect (PCI) express (PCIe) link. PCIe is a point-to-point communication link between two termini. Exemplary aspects of the present disclosure allow the two termini to be in different power states. By allowing the two termini to be in the different power states, an individual terminus may be put into a low-power state even though the other terminus is maintained at a higher-power state. The different power states are enabled by providing switches between a reference clock and respective termini such that the reference clock may selectively be provided to only one terminus of the communication link, allowing that terminus to remain in the higher-power state while the other terminus enters a low-power state that does not require the reference clock.

Abstract: Asymmetric power states on a communication link are disclosed. In one aspect, the communication link is a Peripheral Component Interconnect (PCI) express (PCIe) link. PCIe is a point-to-point communication link between two termini. Exemplary aspects of the present disclosure allow the two termini to be in different power states. By allowing the two termini to be in the different power states, an individual terminus may be put into a low-power state even though the other terminus is maintained at a higher-power state. The different power states are enabled by providing switches between a reference clock and respective termini such that the reference clock may selectively be provided to only one terminus of the communication link, allowing that terminus to remain in the higher-power state while the other terminus enters a low-power state that does not require the reference clock.

Abstract: Fast link training in embedded systems is disclosed. In one aspect, a host takes advantage of situations in which the host is coupled to one or more static devices through a communication bus. In particular, because the one or more devices are static, the host may be provided with information about the one or more devices before start up, so that when the host does perform a start up, the host already knows which device(s) to expect. Accordingly, the host may directly query the expected device(s), and after receipt of response(s) from the expected device(s), may begin link training the expected device(s). By using the provided information about the expected device(s) in this fashion, the host may bypass or skip an initial signal detection step used by conventional link training processes. Bypassing the initial signal detection step may save time, which in turn saves power.

Abstract: Fast link training in embedded systems is disclosed. In one aspect, a host takes advantage of situations in which the host is coupled to one or more static devices through a communication bus. In particular, because the one or more devices are static, the host may be provided with information about the one or more devices before start up, so that when the host does perform a start up, the host already knows which device(s) to expect. Accordingly, the host may directly query the expected device(s), and after receipt of response(s) from the expected device(s), may begin link training the expected device(s). By using the provided information about the expected device(s) in this fashion, the host may bypass or skip an initial signal detection step used by conventional link training processes. Bypassing the initial signal detection step may save time, which in turn saves power.