Abstract: A method of interfacing two components of a computing system is provided wherein the method includes providing a pair of unidirectional, point-to-point buses to transmit data between a master bus controller of the computing system and a slave bus controller of a processor unit of the computing system. The method also includes providing means for transmitting a command packet with an address associated with data pertaining to the command from the master bus controller to the slave bus controller. In addition, the method includes providing means for determining by the slave bus controller whether the slave bus controller can accept the command. The method further includes providing means for transmitting an acknowledgement from the slave bus controller to the master bus controller after the slave bus controller receives a first signaling interval for the command packet if the slave bus controller can accept the command packet.

Abstract: A data processing system includes a plurality of processing units coupled by a plurality of communication links for point-to-point communication such that at least some of the communication between multiple different ones of the processing units is transmitted via intermediate processing units among the plurality of processing units. The communication includes operations having a request and a combined response representing a system response to the request.

Abstract: A cache coherent data processing system includes at least first and second coherency domains. The first coherency domain includes a system memory controller for a system memory and a first processing unit having a first cache memory. The second coherency domain includes a second processing unit having a second cache memory. In the first cache memory, a coherency state field associated with a storage location and an address tag is set to a first coherency state. In response to snooping an exclusive access request specifying a target address matching the address tag, the first cache memory provides a first partial response to the exclusive access request based at least in part upon the first coherency state. In response to snooping the exclusive access request, the memory controller determines whether it is responsible for the target address and provides a second partial response to the exclusive access request based at least in part upon an outcome of the determination.

Abstract: A method of interfacing two components of a computing system is provided wherein the method includes providing a pair of unidirectional, point-to-point buses to transmit data between a master bus controller of the computing system and a slave bus controller of a processor unit of the computing system. The method also includes providing means for transmitting a command packet with an address associated with data pertaining to the command from the master bus controller to the slave bus controller. In addition, the method includes providing means for determining by the slave bus controller whether the slave bus controller can accept the command. The method further includes providing means for transmitting an acknowledgement from the slave bus controller to the master bus controller after the slave bus controller receives a first signaling interval for the command packet if the slave bus controller can accept the command packet.

Abstract: A data processing system includes a plurality of requestors and a memory controller for a system memory. In response to receiving from the requestor a read-type request targeting a memory block in the system memory, the memory controller protects the memory block from modification, and in response to an indication that the memory controller is responsible for servicing the read-type request, the memory controller transmits the memory block to the requestor. Prior to receipt of the memory block by the requestor, the memory controller ends protection of the memory block from modification, and the requestor begins protection of the memory block from modification. In response to receipt of the memory block, the requestor ends its protection of the memory block from modification.

Abstract: A data processing system includes at least a first processing node having an input/output (I/O) controller and a second processing including a memory controller for a memory. The memory controller receives, in order, pipelined first and second DMA write operations from the I/O controller, where the first and second DMA write operations target first and second addresses, respectively. In response to the second DMA write operation, the memory controller establishes a state of a domain indicator associated with the second address to indicate an operation scope including the first processing node. In response to the memory controller receiving a data access request specifying the second address and having a scope excluding the first processing node, the memory controller forces the data access request to be reissued with a scope including the first processing node based upon the state of the domain indicator associated with the second address.

Abstract: A computer implemented method, a data processing system, and a computer usable program code for automatically identifying multiple combinations of operational and non-operational components with a single part number. A non-volatile storage is provided on a part, wherein the part includes a plurality of sub-components. Unavailable sub-components in the plurality of sub-components are identified based on a series of testing to form identified unavailable sub-components. Information of the identified unavailable sub-components is stored into the non-volatile storage.

Abstract: A data processing system, method, and computer-usable medium for recovering from a hang condition in a data processing system. The data processing system includes a collection of coupled processing units. The processing units include a collection of processing unit components such as, two or more processing cores, and a cache array, a processor core master, a cache snooper, and a local hang manager. The local hang manager determines whether at least one component out of the collection of processing unit components has entered into a hang condition. If the local hang manager determines at least one component has entered into a hang condition, a throttling manager throttles the performance of the processing unit in an attempt to break the at least one component out of the hang condition.

Abstract: A system and method of responding to a cache read error with a temporary cache directory column delete. A read command is received at a cache controller. In response to determining that data requested by said read command is stored in a specific data location in the cache, a read of the data is initiated. In response to determining the read of said data results in an error, a column delete indicator for an associativity class including a specific data location to temporarily prevent allocation within the associativity class of storage locations is set. A specific line delete command that marks the specific data location as deleted is issued. In response to the issuing of the specific line delete command, the column delete indicator for the associativity class, such that storage locations within the associativity class other than the specific data location can again be allocated to hold new data is set.

Abstract: A face mask comprises a sealing collar (1) extending around the mouth with a shelf (4) extending under the nose supporting a gel insert (7) that makes sealing contact between the nostrils and a passage (6) through the shelf. A curved, rigid window (30) is a push fit in a central opening (2) of the collar (1) and has a gas inlet (33) attached with it so that the window can be removed or connected with the sealing collar as necessary. The collar (1) supported on the head by a harness (20) having two triangular portions (21) on opposite sides encircling respective ears.

Abstract: Scrubbing logic in a local coherency domain issues to at least one cache hierarchy in a remote coherency domain a domain reset request that forces invalidation of any cached copy of a target memory block then held in said remote coherency domain. A coherency response to said domain reset request is received. In response to said coherency response indicating that said target memory block is not cached in said remote coherency domain, a domain indication of said local coherency domain is updated to indicate that said target memory block is cached, if at all, only within said local coherency domain.

Abstract: Scrubbing logic in a local coherency domain issues a domain query request to at least one cache hierarchy in a remote coherency domain. The domain query request is a non-destructive probe of a coherency state associated with a target memory block by the at least one cache hierarchy. A coherency response to the domain query request is received. In response to the coherency response indicating that the target memory block is not cached in the remote coherency domain, a domain indication in the local coherency domain is updated to indicate that the target memory block is cached, if at all, only within the local coherency domain.

Abstract: In response to execution of program code, a control register within scrubbing logic in a local coherency domain is initialized with at least a target address of a target memory block. In response to the initialization, the scrubbing logic issues to at least one cache hierarchy in a remote coherency domain a domain indication scrubbing request targeting a target memory block that may be cached by the at least one cache hierarchy. In response to receipt of a coherency response indicating that the target memory block is not cached in the remote coherency domain, a domain indication in the local coherency domain is updated to indicate that the target memory block is cached, if at all, only within the local coherency domain.

Abstract: A method and apparatus for invalidating cache lines during direct memory access (DMA) write operations are disclosed. Initially, a multi-cache line DMA request is issued by a peripheral device. The multi-cache line DMA request is snooped by a cache memory. A determination is then made as to whether or not the cache memory includes a copy of data stored in the system memory locations to which the multi-cache line DMA request are directed. In response to a determination that the cache memory includes a copy of data stored in the system memory locations to which the multi-cache line DMA request are directed, multiple cache lines within the cache memory are consecutively invalidated.

Abstract: A method, apparatus, and computer instructions are provided by the present invention to automatically recover from a failed node concurrent maintenance operation. A control logic is provided to send a first test command to processors of a new node. If the first test command is successful, a second test command is sent to all processors or to the remaining nodes if nodes are removed. If the second command is successful, system operation is resumed with the newly configured topology with either nodes added or removed. If the response is incorrect or a timeout has occurred, the control logic restores values to the current mode register and sends a third test command to check for an error. A fatal system attention is sent to a service processor or system software if an error is encountered. If no error, system operation is resumed with previously configured topology.

Abstract: A method and apparatus for invalidating entries within a translation control entry (TCE) cache are disclosed. A host bridge is coupled between a group of processors and a group of adaptors. The host bridge includes a TCE cache. The TCE cache contains the most-recently use copies of TCEs in a TCE table located in a system memory. In response to a modification to a TCE in the TCE table by one of the processors, a memory mapped input/output (MMIO) Store is sent to a TCE invalidate register to specify an address of the modified TCE. The data within the TCE invalidate register is then utilized to generate a command for invalidating an entry in the TCE cache containing an unmodified copy of the modified TCE in the TCE table. The command is subsequently sent to the host bridge to invalidate the entry in the TCE cache.

Abstract: The present invention, a multiprocessor chip pervasive command interface, collects different types of pervasive commands into individual queues for each command type. As permitted by various grouping rules, valid commands are grouped together into one single command and placed on a functional interchip communications bus. This grouping of commands maximizes pervasive command bandwidth while the use of the functional bus minimizes the number of interchip connections.

Abstract: A method, system, and device for enabling intervention across same-level cache memories. In a preferred embodiment, responsive to a cache miss in a first cache memory a direct intervention request is sent from the first cache memory to a second cache memory requesting a direct intervention that satisfies the cache miss. In an alternate embodiment, direct intervention is utilized to access a same-level victim cache.

Abstract: A method, computer program product and system for switching a defective signal line with a spare signal line without shutting down the computer system. A service processor monitors error correction code (ECC) check units configured to detect an error in a signal line. If an ECC check unit detects an error rate that exceeds a threshold, then the signal line with such an error rate may be said to be “defective.” The service processor configures switch control units in the driver/receiver pair associated with the defective signal line to be able to switch the defective signal line with a spare line upon receipt of a command from a memory controller switch control unit. In this manner, the system is not deactivated in order to switch a defective signal line with a spare line thereby reducing the time that the processor cannot send information to the memory buffers.

Abstract: A data processing system includes a plurality of processing units coupled for communication by a communication link and a configuration register. The configuration register has a plurality of different settings each corresponding to a respective one of a plurality of different link information allocations. Information is communicated over the communication link in accordance with a particular link information allocation among the plurality of link information allocations determined by a respective setting of the configuration register.