Abstract: A mechanism programming a direct memory access engine operating as a multithreaded processor is provided. A plurality of programs is received from a host processor in a local memory associated with the direct memory access engine. A request is received in the direct memory access engine from the host processor indicating that the plurality of programs located in the local memory is to be executed. The direct memory access engine executes two or more of the plurality of programs without intervention by a host processor. As each of the two or more of the plurality of programs completes execution, the direct memory access engine sends a completion notification to the host processor that indicates that the program has completed execution.

Abstract: A mechanism for communicating instructions and data between a processor and external devices are provided. The mechanism makes use of a channel interface as the primary mechanism for communicating between the processor and a memory flow controller. The channel interface provides channels for communicating with processor facilities, memory flow control facilities, machine state registers, and external processor interrupt facilities, for example. These channels may be designated as blocking or non-blocking. With blocking channels, when no data is available to be read from the corresponding registers, or there is no space available to write to the corresponding registers, the processor is placed in a low power “stall” state. The processor is automatically awakened, via communication across the blocking channel, when data becomes available or space is freed. Thus, the channels of the present invention permit the processor to stay in a low power state.

Abstract: A mechanism is provided for resolving livelock conditions in a multiple processor data processing system. When a bus unit detects a timeout condition, or potential timeout condition, the bus unit activates a livelock resolution request signal. A livelock resolution unit receives livelock resolution requests from the bus units and signals an attention to a control processor. The control processor performs actions to attempt to resolve the livelock condition. Once a bus unit that issued a livelock resolution request has managed to successfully issue its command, it deactivates its livelock resolution request. If all livelock resolution request signals are deactivated, then the control processor instructs the bus and all bus units to resume normal activity. On the other hand, if the control processor determines that a predetermined amount of time passes without any progress being made, it determines that a hang condition has occurred.

Abstract: The present invention provides a method, system, and computer program product for displaying images of conference call participants. A method in accordance with an embodiment of the present invention includes receiving a call from a user to join a conference call, obtaining a phone number of the user, matching the phone number to a stored graphical representation, and distributing and displaying the matching graphical representation to a predetermined set of users. A voice identification/recognition process can also be used to match the user to a stored graphical representation.

Abstract: A method for communicating instructions and data between a processor and external devices are provided. The method makes use of a channel interface as the primary mechanism for communicating between the processor and a memory flow controller. The channel interface provides channels for communicating with processor facilities, memory flow control facilities, machine state registers, and external processor interrupt facilities, for example. These channels may be designated as blocking or non-blocking. With blocking channels, when no data is available to be read from the corresponding registers, or there is no space available to write to the corresponding registers, the processor is placed in a low power “stall” state. The processor is automatically awakened, via communication across the blocking channel, when data becomes available or space is freed. Thus, the channels of the present invention permit the processor to stay in a low power state.

Abstract: A mechanism programming a direct memory access engine operating as a multithreaded processor is provided. A plurality of programs is received from a host processor in a local memory associated with the direct memory access engine. A request is received in the direct memory access engine from the host processor indicating that the plurality of programs located in the local memory is to be executed. The direct memory access engine executes two or more of the plurality of programs without intervention by a host processor. As each of the two or more of the plurality of programs completes execution, the direct memory access engine sends a completion notification to the host processor that indicates that the program has completed execution.

Abstract: A mechanism for programming a direct memory access engine operating as a single thread processor is provided. A program is received from a host processor in a local memory associated with the direct memory access engine. A request is received in the direct memory access engine from the host processor indicating that the program located in the local memory is to be executed. The direct memory access engine executes the program without intervention by a host processor. Responsive to the program completing execution, the direct memory access engine sends a completion notification to the host processor that indicates that the program has completed execution.

Abstract: Mechanisms for priority control in resource allocation is provided. With these mechanisms, when a unit makes a request to a token manager, the unit identifies the priority of its request as well as the resource which it desires to access and the unit's resource access group (RAG). This information is used to set a value of a storage device associated with the resource, priority, and RAG identified in the request. When the token manager generates and grants a token to the RAG, the token is in turn granted to a unit within the RAG based on a priority of the pending requests identified in the storage devices associated with the resource and RAG. Priority pointers are utilized to provide a round-robin fairness scheme between high and low priority requests within the RAG for the resource.

Abstract: A system for limiting the size of a local storage of a processor is provided. A facility is provided in association with a processor for setting a local storage size limit. This facility is a privileged facility and can only be accessed by the operating system running on a control processor in the multiprocessor system or the associated processor itself. The operating system sets the value stored in the local storage limit register when the operating system initializes a context switch in the processor. When the processor accesses the local storage using a request address, the local storage address corresponding to the request address is compared against the local storage limit size value in order to determine if the local storage address, or a modulo of the local storage address, is used to access the local storage.

Abstract: An I/O address translation method for specifying relaxed ordering for I/O accesses are provided. With the apparatus and method, storage ordering (SO) bits are provided in an I/O address translation data structure, such as a page table or segment table. These SO bits define the order in which reads and/or writes initiated by an I/O device may be performed. These SO bits are combined with an ordering bit, e.g., the Relaxed Ordering Attribute bit of PCI Express, on the I/O interface. The weaker ordering indicated either in the I/O address translation data structure or in the I/O interface relaxed ordering bit is used to control the order in which I/O operations may be performed.

Abstract: A mechanism is provided for efficiently managing the operation of a translation buffer. The mechanism is utilized to pre-load a translation buffer to prevent poor operation as a result of slow warming of a cache. A software pre-load mechanism may be provided for preloading a translation look aside buffer (TLB) via a hardware implemented controller. Following preloading of the TLB, control of accessing the TLB may be handed over to the hardware implemented controller. Upon an application context switch operation, the software preload mechanism may be utilized again to preload the TLB with new translation information for the newly active application instance.

Abstract: A mechanism for priority control in resource allocation for low request rate, latency-sensitive units is provided. With this mechanism, when a unit makes a request to a token manager, the unit identifies the priority of its request as well as the resource which it desires to access and the unit's resource access group (RAG). This information is used to set a value of a storage device associated with the resource, priority, and RAG identified in the request. When the token manager generates and grants a token to the RAG, the token is in turn granted to a unit within the RAG based on a priority of the pending requests identified in the storage devices associated with the resource and RAG. Priority pointers are utilized to provide a round-robin fairness scheme between high and low priority requests within the RAG for the resource.

Abstract: A method, system, apparatus, and article of manufacture for performing cacheline polling utilizing store and reserve and load when reservation lost instructions is disclosed. In one embodiment a method is provided which comprises storing a buffer flag busy indicator data value within a first cacheable memory location and setting a load/store operation reservation on said first cacheable memory location via a store and reserve instruction. In the described embodiment, a data value stored within the first cacheable memory location is accessed via a conditional load instruction in response to a determination that the load/store operation reservation on the first cacheable memory location has been reset. Conversely, execution of the conditional load instruction is stalled in response to a determination that the load/store operation reservation on the first cacheable memory location has not been reset.

Abstract: A system and method for communicating with a processor event facility are provided. The system and method make use of a channel interface as the primary mechanism for communicating with the processor event facility. The channel interface provides channels for communicating with processor facilities, memory flow control facilities, machine state registers, and external processor interrupt facilities, for example. These channels may be designated as blocking or non-blocking. With blocking channels, when no data is available to be read from the corresponding registers, or there is no space available to write to the corresponding registers, the processor is placed in a low power “stall” state. The processor is automatically awakened, via communication across the blocking channel, when data becomes available or space is freed. Thus, the channels of the present invention permit the processor to stay in a low power state.

Abstract: A load when reservation lost instruction for performing cacheline polling is disclosed. Initially, a first process requests an action to be performed by a second process. The request is made via a store operation to a cacheable memory location. The first process then reads the cacheable memory location via a conditional load operation to determine whether or not the requested action has been completed by the second process, and the first process sets a reservation at the cacheable memory location if the requested action has not been completed by the second process. The conditional load operation of the first process is stalled until the reservation at the cacheable memory location has been lost. After the requested action has been completed, the reservation in the cacheable memory location is reset by the second process.

Abstract: A system for limiting the size of a local storage of a processor is provided. A facility is provided in association with a processor for setting a local storage size limit. This facility is a privileged facility and can only be accessed by the operating system running on a control processor in the multiprocessor system or the associated processor itself. The operating system sets the value stored in the local storage limit register when the operating system initializes a context switch in the processor. When the processor accesses the local storage using a request address, the local storage address corresponding to the request address is compared against the local storage limit size value in order to determine if the local storage address, or a modulo of the local storage address, is used to access the local storage.

Abstract: A mechanism is provided for resolving livelock conditions in a multiple processor data processing system. When a bus unit detects a timeout condition, or potential timeout condition, the bus unit activates a livelock resolution request signal. A livelock resolution unit receives livelock resolution requests from the bus units and signals an attention to a control processor. The control processor performs actions to attempt to resolve the livelock condition. Once a bus unit that issued a livelock resolution request has managed to successfully issue its command, it deactivates its livelock resolution request. If all livelock resolution request signals are deactivated, then the control processor instructs the bus and all bus units to resume normal activity. On the other hand, if the control processor determines that a predetermined amount of time passes without any progress being made, it determines that a hang condition has occurred.

Abstract: A buffer, a method, and a computer program product for DMA transfers are provided that are designed to save memory space within a local memory of a processor. The buffer is a return buffer with a portion reserved for DMA lists. A DMA controller accomplishes DMA transfers by: reading address elements from a DMA list located in the DMA list portion; reading the corresponding data from system memory; and copying the corresponding data to the return buffer portion. This buffer saves space because when the buffer begins to fill up the corresponding return data can overwrite the data in the DMA list. Accordingly, the DMA list overlays on top of the return buffer, such that the return data can destruct the DMA list and the extra storage space for the DMA list is saved.

Abstract: Systems and methods for positioning thermal sensors within an integrated circuit in a manner that provides useful thermal measurements corresponding to different parts of the integrated circuit. In one embodiment, an integrated circuit includes multiple, duplicate functional blocks. A separate thermal sensor is coupled to each of the duplicate functional blocks, preferably in the same relative location on each of the duplicate functional blocks, and preferably at a hotspot. One embodiment also includes thermal sensors on one or more functional blocks of other types in the integrated circuit. One embodiment includes a thermal sensor positioned at a cool spot, such as at the edge of the integrated circuit chip. Each of the thermal sensors may have ports to enable power and ground connections or data connections between the sensors and external components or devices.

Abstract: A method and apparatus are provided for calibrating digital thermal sensors. A processor chip with a plurality of digital thermal sensors receives an analog voltage. A test circuit coupled to the processor chip receives a clock signal and a register coupled to the test circuit outputs a value on each clock cycle to a digital thermal sensor in the plurality of digital thermal sensors. The digital thermal sensor transitions an output state in response to the value of the register received in the digital thermal sensor equaling a temperature threshold of the digital thermal sensor. The value of the register at the point of transition is used to calibrate the digital thermal sensor. An incrementer increments the value of the register on each clock cycle in response to the value of the register received in the digital thermal sensor failing to equal the temperature threshold of the digital thermal sensor.