Abstract: In an embodiment, a non-transparent memory unit is provided which includes a non-transparent memory and a control circuit. The control circuit may manage the non-transparent memory as a set of non-transparent memory blocks. Software executing on one or more processors may request a non-transparent memory block in which to process data. The control circuit may allocate a first block, and may return an address (or other indication) of the allocated block so that the software can access the block. The control circuit may also provide automatic data movement between the non-transparent memory and a main memory system to which the non-transparent memory unit is coupled. For example, the automatic data movement may include filling data from the main memory system to the allocated block, or flushing the data in the allocated block to the main memory system after the processing of the allocated block is complete.

Abstract: In one embodiment, a processor comprises a data cache configured to store a plurality of cache blocks and a control unit coupled to the data cache. The control unit is configured to flush the plurality of cache blocks from the data cache responsive to an indication that the processor is to transition to a low power state in which one or more clocks for the processor are inhibited.

Abstract: In one embodiment, an apparatus comprises an interconnect; at least one processor coupled to the interconnect; and at least one memory controller coupled to the interconnect. The memory controller is programmable by the processor into a loopback test mode of operation and, in the loopback test mode, the memory controller is configured to receive a first write operation from the processor over the interconnect. The memory controller is configured to route write data from the first write operation through a plurality of drivers and receivers connected to a plurality of data pins that are capable of connection to one or more memory modules. The memory controller is further configured to return the write data as read data on the interconnect for a first read operation received from the processor on the interconnect.

Abstract: In one embodiment, an apparatus comprises an interconnect; at least one processor coupled to the interconnect; and at least one memory controller coupled to the interconnect. The memory controller is programmable by the processor into a loopback test mode of operation and, in the loopback test mode, the memory controller is configured to receive a first write operation from the processor over the interconnect. The memory controller is configured to route write data from the first write operation through a plurality of drivers and receivers connected to a plurality of data pins that are capable of connection to one or more memory modules. The memory controller is further configured to return the write data as read data on the interconnect for a first read operation received from the processor on the interconnect.

Abstract: In one embodiment, an apparatus comprises a first clocked storage device operable in a first clock domain corresponding to a first clock signal. The first clocked storage device has an input coupled to receive one or more bits transmitted on the input from a second clock domain corresponding to a second clock signal. The apparatus further comprises control circuitry configured to ensure that a change in a value of the one or more bits transmitted on the input meets setup and hold time requirements of the first clocked storage device. The control circuitry is responsive to a sample history of one of the first clock signal or the second clock signal to detect a phase relationship between the first clock signal and the second clock signal on each clock cycle to ensure the change meets the setup and hold time requirements.

Abstract: An interface unit may comprise a buffer configured to store requests that are to be transmitted on an interconnect and a control unit coupled to the buffer. In one embodiment, the control unit is coupled to receive a retry response from the interconnect during a response phase of a first transaction for a first request stored in the buffer. The control unit is configured to record an identifier supplied on the interconnect with the retry response that identifies a second transaction that is in progress on the interconnect. The control unit is configured to inhibit reinitiation of the first transaction at least until detecting a second transmission of the identifier. In another embodiment, the control unit is configured to assert a retry response during a response phase of a first transaction responsive to a snoop hit of the first transaction on a first request stored in the buffer for which a second transaction is in progress on the interconnect.

Abstract: An interface unit may comprise a buffer configured to store requests that are to be transmitted on an interconnect and a control unit coupled to the buffer. In one embodiment, the control unit is coupled to receive a retry response from the interconnect during a response phase of a first transaction for a first request stored in the buffer. The control unit is configured to record an identifier supplied on the interconnect with the retry response that identifies a second transaction that is in progress on the interconnect. The control unit is configured to inhibit reinitiation of the first transaction at least until detecting a second transmission of the identifier. In another embodiment, the control unit is configured to assert a retry response during a response phase of a first transaction responsive to a snoop hit of the first transaction on a first request stored in the buffer for which a second transaction is in progress on the interconnect.

Abstract: In one embodiment, a switch is configured to be coupled to an interconnect. The switch comprises a plurality of storage locations and an arbiter control circuit coupled to the plurality of storage locations. The plurality of storage locations are configured to store a plurality of requests transmitted by a plurality of agents. The arbiter control circuit is configured to arbitrate among the plurality of requests stored in the plurality of storage locations. A selected request is the winner of the arbitration, and the switch is configured to transmit the selected request from one of the plurality of storage locations onto the interconnect. In another embodiment, a system comprises a plurality of agents, an interconnect, and the switch coupled to the plurality of agents and the interconnect. In another embodiment, a method is contemplated.

Abstract: In one embodiment, an apparatus comprises an interconnect; at least one processor coupled to the interconnect; and at least one memory controller coupled to the interconnect. The memory controller is programmable by the processor into a loopback test mode of operation and, in the loopback test mode, the memory controller is configured to receive a first write operation from the processor over the interconnect. The memory controller is configured to route write data from the first write operation through a plurality of drivers and receivers connected to a plurality of data pins that are capable of connection to one or more memory modules. The memory controller is further configured to return the write data as read data on the interconnect for a first read operation received from the processor on the interconnect.

Abstract: In one embodiment, an apparatus comprises a first clocked storage device operable in a first clock domain corresponding to a first clock signal. The first clocked storage device has an input coupled to receive one or more bits transmitted on the input from a second clock domain corresponding to a second clock signal. The apparatus further comprises control circuitry configured to ensure that a change in a value of the one or more bits transmitted on the input meets setup and hold time requirements of the first clocked storage device. The control circuitry is responsive to a sample history of one of the first clock signal or the second clock signal to detect a phase relationship between the first clock signal and the second clock signal on each clock cycle to ensure the change meets the setup and hold time requirements.

Abstract: In one embodiment, an apparatus comprises a first clocked storage device operable in a first clock domain corresponding to a first clock signal. The first clocked storage device has an input coupled to receive one or more bits transmitted on the input from a second clock domain corresponding to a second clock signal. The apparatus further comprises control circuitry configured to ensure that a change in a value of the one or more bits transmitted on the input meets setup and hold time requirements of the first clocked storage device. The control circuitry is responsive to a sample history of one of the first clock signal or the second clock signal to detect a phase relationship between the first clock signal and the second clock signal on each clock cycle to ensure the change meets the setup and hold time requirements.

Abstract: In an embodiment, a non-transparent memory unit is provided which includes a non-transparent memory and a control circuit. The control circuit may manage the non-transparent memory as a set of non-transparent memory blocks. Software executing on one or more processors may request a non-transparent memory block in which to process data. The control circuit may allocate a first block, and may return an address (or other indication) of the allocated block so that the software can access the block. The control circuit may also provide automatic data movement between the non-transparent memory and a main memory system to which the non-transparent memory unit is coupled. For example, the automatic data movement may include filling data from the main memory system to the allocated block, or flushing the data in the allocated block to the main memory system after the processing of the allocated block is complete.

Abstract: In an embodiment, a cache stores tags for cache blocks stored in the cache. Each tag may include an indication identifying which of two or more replacement policies supported by the cache is in use for the corresponding cache block, and a replacement record indicating the status of the corresponding cache block in the replacement policy. Requests may include a replacement attribute that identifies the desired replacement policy for the cache block accessed by the request. If the request is a miss in the cache, a cache block storage location may be allocated to store the corresponding cache block. The tag associated with the cache block storage location may be updated to include the indication of the desired replacement policy, and the cache may manage the block in accordance with the policy. For example, in an embodiment, the cache may support both an LRR and an LRU policy.

Abstract: In one embodiment, a memory that is delineated into transparent and non-transparent portions. The transparent portion may be controlled by a control unit coupled to the memory, along with a corresponding tag memory. The non-transparent portion may be software controlled by directly accessing the non-transparent portion via an input address. In an embodiment, the memory may include a decoder configured to decode the address and select a location in either the transparent or non-transparent portion. Each request may include a non-transparent attribute identifying the request as either transparent or non-transparent. In an embodiment, the size of the transparent portion may be programmable. Based on the non-transparent attribute indicating transparent, the decoder may selectively mask bits of the address based on the size to ensure that the decoder only selects a location in the transparent portion.

Abstract: In one embodiment, an apparatus comprises an interconnect; at least one processor coupled to the interconnect; and at least one memory controller coupled to the interconnect. The memory controller is programmable by the processor into a loopback test mode of operation and, in the loopback test mode, the memory controller is configured to receive a first write operation from the processor over the interconnect. The memory controller is configured to route write data from the first write operation through a plurality of drivers and receivers connected to a plurality of data pins that are capable of connection to one or more memory modules. The memory controller is further configured to return the write data as read data on the interconnect for a first read operation received from the processor on the interconnect.

Abstract: In one embodiment, a processor comprises a data cache configured to store a plurality of cache blocks and a control unit coupled to the data cache. The control unit is configured to flush the plurality of cache blocks from the data cache responsive to an indication that the processor is to transition to a low power state in which one or more clocks for the processor are inhibited.

Abstract: In one embodiment, a switch is configured to be coupled to an interconnect. The switch comprises a plurality of storage locations and an arbiter control circuit coupled to the plurality of storage locations. The plurality of storage locations are configured to store a plurality of requests transmitted by a plurality of agents. The arbiter control circuit is configured to arbitrate among the plurality of requests stored in the plurality of storage locations. A selected request is the winner of the arbitration, and the switch is configured to transmit the selected request from one of the plurality of storage locations onto the interconnect. In another embodiment, a system comprises a plurality of agents, an interconnect, and the switch coupled to the plurality of agents and the interconnect. In another embodiment, a method is contemplated.

Abstract: In one embodiment, a processor comprises a data cache configured to store a plurality of cache blocks and a control unit coupled to the data cache. The control unit is configured to flush the plurality of cache blocks from the data cache responsive to an indication that the processor is to transition to a low power state in which one or more clocks for the processor are inhibited.

Abstract: In one embodiment, a switch is configured to be coupled to an interconnect. The switch comprises a plurality of storage locations and an arbiter control circuit coupled to the plurality of storage locations. The plurality of storage locations are configured to store a plurality of requests transmitted by a plurality of agents. The arbiter control circuit is configured to arbitrate among the plurality of requests stored in the plurality of storage locations. A selected request is the winner of the arbitration, and the switch is configured to transmit the selected request from one of the plurality of storage locations onto the interconnect. In another embodiment, a system comprises a plurality of agents, an interconnect, and the switch coupled to the plurality of agents and the interconnect. In another embodiment, a method is contemplated.

Abstract: In one embodiment, a processor comprises a scheduler configured to issue a first instruction operation to be executed and an execution core coupled to the scheduler. Configured to execute the first instruction operation, the execution core comprises a plurality of replay sources configured to cause a replay of the first instruction operation responsive to detecting at least one of a plurality of replay cases. The scheduler is configured to inhibit issuance of the first instruction operation subsequent to the replay for a subset of the plurality of replay cases. The scheduler is coupled to receive an acknowledgement indication corresponding to each of the plurality of replay cases in the subset, and is configured to inhibit issuance of the first instruction operation until the acknowledgement indication is asserted that corresponds to an identified replay case of the subset.