摘要:
A method and circuit for implementing serial link training sequences, and a design structure on which the subject circuit resides are provided. A transmitter device transmits a training sequence (TS) pattern; then the transmitter device transmits random data for a predefined time duration. The steps of transmitting the TS-pattern, then transmitting the random data for the fixed time duration are repeated. A receiver device detecting a plurality of the TS-patterns separated by the predefined time interval of random data, performs receiver initialization steps. The receiver device performs a plurality of receiver initialization steps including, for example, acquiring byte lock, and a link width determination.
摘要:
An early return indication is used to notify a first communications interface, prior to a response being received from any of a plurality of sources coupled to a second communications interface, that the return data can be used by the first communications interface when it is received thereby from a source of the return data if the source has an exclusive copy of the return data. By doing so, the first communications interface can often prepare for forwarding the return data over its associated communication link such that the data can be forwarded with little or no latency once the data is retrieved from its source, and may be able to initiate the return of data over the communication link prior to all responses being received from the other sources. The early return indication may also serves as an early coherency indication in that the first communications interface is no longer required to wait for updating of a coherency directory to complete prior to forwarding the return data over the communication link.
摘要:
In a shared memory architecture, early coherency indication is used to notify a communications interface, prior to the data for a memory request is returned, and prior to updating a coherency directory in response to the memory request, that the return data can be used by the communications interface when it is received thereby from a source of the return data. By doing so, the communications interface can often begin forwarding the return data over its associated communication link with little or no latency once the data is retrieved from its source. In addition, the communications interface is often no longer required to wait for updating of the coherency directory to complete prior to forwarding the return data over the communication link. As such, the overall latency for handling the memory request is typically reduced.
摘要:
A method and circuit for implementing known scrambling relationship among multiple serial links, and a design structure on which the subject circuit resides are provided. A transmit Linear Feedback Shift Register (LFSR) is provided with each of the multiple serial links for scrambling transmitted data. A receive Linear Feedback Shift Register (LFSR) is provided with each of the multiple serial links for descrambling received data. Each of the transmit LFSRs is initialized to a unique value. Each transmit LFSR conveys a current unique value to a receive LFSR for synchronizing the transmit LFSR and receive LFSR to begin scrambling and descrambling data.
摘要:
A method and circuit for implementing known scrambling relationship among multiple serial links, and a design structure on which the subject circuit resides are provided. A transmit Linear Feedback Shift Register (LFSR) is provided with each of the multiple serial links for scrambling transmitted data. A receive Linear Feedback Shift Register (LFSR) is provided with each of the multiple serial links for descrambling received data. Each of the transmit LFSRs is initialized to a unique value. Each transmit LFSR conveys a current unique value to a receive LFSR for synchronizing the transmit LFSR and receive LFSR to begin scrambling and descrambling data.
摘要:
A method and circuit for implementing serial link training sequences, and a design structure on which the subject circuit resides are provided. A transmitter device transmits a training sequence (TS) pattern; then the transmitter device transmits random data for a predefined time duration. The steps of transmitting the TS-pattern, then transmitting the random data for the fixed time duration are repeated. A receiver device detecting a plurality of the TS-patterns separated by the predefined time interval of random data, performs receiver initialization steps. The receiver device performs a plurality of receiver initialization steps including, for example, acquiring byte lock, and a link width determination.
摘要:
A method and circuit for implementing variable length packets to embed extra control information in an interconnect system, and a design structure on which the subject circuit resides are provided. Packets are defined to include an End-to-End (ETE) Flow Unit within packet (Flit) count field in the packet header. The packet header also includes its own CRC field. When a nonzero ETE flit count field is received in an incoming packet from an incoming link, the specified number of embedded ETE flits is removed from the packet and is used the same as if the control information arrived in its own packet.
摘要:
A clustered computer system, bridge device and method include support for an atomic ownership change operation that ensures orderly and reliable ownership management of an input/output (I/O) bridge device. A lock indicator is associated with a bridge device, and is used to indicate a “locked” or “unlocked” status of the bridge device. Whenever the lock indicator indicates that the bridge device is unlocked, an atomic operation such as a read request to a lock indicator register is utilized to both set the indicator to indicate a locked status for the bridge device, and to associate the bridge device with a source node that initiated the atomic operation. In connection with the lock indicator, write access to one or more configuration parameter registers is controlled such that only the node that is associated with the bridge device is permitted to update such configuration parameter registers.
摘要:
A method and apparatus is disclosed which enhances the integrity of transmitted data or detects when random data is being received which might indicate that a receiver or a transmitter is open or that random data is otherwise being transmitted. A stream of data transmitted in packets having an error code associated with each packet is received into a receiver. The receiver has an error code checker to check the error code of each packet to determine if the data packet has been transmitted error-free. The results of the error checks for n sequential packets are stored in a shift register or counter. An incoming packet then undergoes an error code check and the results of the previous n sequential packets are considered. If a predetermined number of the previous n sequential packets has a transmission error n, then the method decides to reject or accept the error packet based on the quality of data integrity. When a 32-bit CRC error code is used, an 8-bit shift register is sufficient to prevent the acceptance of a packet of random data that may otherwise be accepted.
摘要:
A method and circuit for implementing ordered and reliable transfer of packets while spraying packets over multiple links, and a design structure on which the subject circuit resides are provided. Each source interconnect chip maintains a spray mask including multiple available links for each destination chip for spraying packets across multiple links of a local rack interconnect system. Each packet is assigned an End-to-End (ETE) sequence number in the source interconnect chip that represents the packet position in an ordered packet stream from the source device. The destination interconnect chip uses the ETE sequence numbers to reorder the received sprayed packets into the correct order before sending the packets to the destination device.