Abstract: A system and method for flexible multiple protocols are presented. A device's logical layer may be dynamically configured on a per interface basis to communicate with external devices in a coherent or a non-coherent mode. In coherent mode, commands such as coherency protocol, system commands, and snoop response pass from the device's internal system bus to an external device, thereby creating a logical extension of the devices internal system bus. In non-coherent mode, the input-output bus unit receives commands from the internal system bus and generates non-coherent input-output commands, which are eventually received by an external device.

Abstract: In a first aspect, a first method of testing a link between a first chip and a second chip is provided. The first method includes the steps of, while operating in a test mode, (1) transmitting test data of sufficient length to enable exercising of worst case transitions from the first chip to the second chip via the link; and (2) performing cyclic redundancy checking (CRC) on the test data to test the link. Numerous other aspects are provided.

Abstract: In a first aspect, a first method of testing a link between a first chip and a second chip is provided. The first method includes the steps of, while operating in a test mode, (1) transmitting test data of sufficient length to enable exercising of worst case transitions from the first chip to the second chip via the link; and (2) performing cyclic redundancy checking (CRC) on the test data to test the link. Numerous other aspects are provided.

Abstract: A method and apparatus are provided for implementing data mapping using a shuffle algorithm. An output shuffler and an input shuffler convert a physical data group to a plurality of data subgroups. The physical data group includes a plurality of bits and each subgroup includes a subplurality of bits. The output shuffler performs an output shuffle sequence for providing a predefined output pattern of ordered subplurality data bits. The predefined output pattern of ordered subplurality data bits is applied to the input shuffler. The input shuffler performs a reverse shuffle sequence. For each shuffle transfer a number of first header bytes of a packet are located at a first one of a plurality of physical layer links. Both the output shuffler and the input shuffler are implemented with minimized logic required to keep a largest multiplexer as a 4-to-1 multiplexer, resulting in minimal area and power being used for implementing the shuffle sequence and reverse shuffle sequence.

Abstract: The present invention provides for an integrated circuit (IC) bus system. A local IC is coupled to a remote IC through a bus interface. A local memory is coupled to the local IC. A bus interface controller is employable to track data transfer requests from the remote IC for data address that are contained within at least one segment of the first partitioned memory range. The bus interface controller is further employable to stop the forwarding of a data transfer request generated within the local IC to the remote IC, if the memory segment count corresponding to the data address of the locally generated data transfer request equals zero.

Abstract: An improved method and apparatus for resource arbitration. Four priority classes, managed high (MH), managed low (ML), opportunistic high (OH) and opportunistic low (OL), are defined. A priority class is assigned to each resource access request. An access request concentrator (ARC) is created for each resource, through which the resource is accessed. An access request is chosen at each ARC using the priority order MH, ML, OH, and OL, in decreasing order of priority. If OH priority class resource access requests are locked out, the priority order is temporarily changed to OH, OL, MH, and ML, in decreasing order of priority. If OL priority class resource access requests are locked out, the priority order is temporarily changed to MH, OL, OH, and ML, in decreasing order of priority.

Abstract: A method and apparatus are provided for implementing data mapping using a shuffle algorithm. An output shuffler and an input shuffler convert a physical data group to a plurality of data subgroups. The physical data group includes a plurality of bits and each subgroup includes a subplurality of bits. The output shuffler performs an output shuffle sequence for providing a predefined output pattern of ordered subplurality data bits. The predefined output pattern of ordered subplurality data bits is applied to the input shuffler. The input shuffler performs a reverse shuffle sequence. For each shuffle transfer a number of first header bytes of a packet are located at a first one of a plurality of physical layer links. Both the output shuffler and the input shuffler are implemented with minimized logic required to keep a largest multiplexer as a 4-to-1 multiplexer, resulting in minimal area and power being used for implementing the shuffle sequence and reverse shuffle sequence.

Abstract: The present invention provides for dynamically determining a ratio of forwarded packets to injected packets to be transmitted in a bus ring. At least one forwarded packet is received into a first queue. An injected packet is received into a second queue. A determination, or snapshot, of the number of forwarded packets in the first queue due to the presence of the injected packet in the second queue is triggered. Packets corresponding to the snapshot are transmitted. After the packets are transmitted, if there is another injected packet stored in the second queue, another snapshot is performed. Packets corresponding to this snapshot are transmitted, and so on.

Abstract: The present invention provides for an integrated circuit (IC) bus system. A local IC is coupled to a remote IC through a bus interface. A local memory is coupled to the local IC. A bus interface controller is employable to track data transfer requests from the remote IC for data address that are contained within at least one segment of the first partitioned memory range. The bus interface controller is further employable to stop the forwarding of a data transfer request generated within the local IC to the remote IC, if the memory segment count corresponding to the data address of the locally generated data transfer request equals zero.

Abstract: A method of providing maintenance for a memory device of a computer system without interrupting operation of the computer system, by partially mirroring a primary memory array in a secondary memory array, wherein the secondary memory array has a different amount of available memory than the primary memory array. Values are copied from the primary memory array to the permanent storage device, allowing the primary memory array to quiesce and be serviced while using the secondary memory array to operate the computer system. Thereafter, the primary memory array is brought on-line, and the mirrored values are written back from the secondary memory array to the primary memory array. The memory service program itself may be embedded in the operating system. In an illustrative embodiment, the primary memory array is located on a first removable memory card, and the secondary memory array is located on a second removable memory card. The amount of memory available in the secondary memory array may be programmable.

Abstract: In a data processing system, data from an input buffer is compressed to produce a compressed data set in a compressed data buffer, wherein the compressed data set has a Lempel-Ziv compressed data format having raw-byte tokens and string tokens. The string tokens in the compressed data set each have a predetermined number of bits, thereby facilitating efficient, high-speed parsing of tokens during subsequent decompression of the compressed data set. In some embodiments, the raw-byte tokens and the string tokens have the same predetermined number of bits.

Abstract: In a data processing system having a history buffer for storing previously decompressed data and an output buffer having at least N bytes, wherein N is greater than 1, a group of input tokens is received from an input buffer. Each input token is either a raw-byte token or a string token, wherein each string token includes a pointer and a length. Thereafter, the process outputs, to the output buffer, decompressed bytes taken from each of the raw-byte tokens within the group of input tokens. The process then determines whether each of the pointers in the string tokens points to data previously stored in the history buffer or points to data within one of the raw-byte tokens within the group of input tokens, which have not yet been stored in the history buffer. For each of the pointers that points to data stored in the history buffer, decompressed bytes pointed to in the history buffer by the pointer and the length are output to the output buffer.

Abstract: A data compression utilization method and apparatus are provided for a computer main store. An amount of unused memory in the computer system main store is dynamically calculated and compared with a plurality of predefined threshold values. One interrupt of a plurality of predefined interrupts is selectively generated responsive to the compared values. Then the usage of the computer system main store is adjusted responsive to the generated interrupt.