Abstract: The present invention provides for authenticating code and/or data and providing a protected environment for execution. The present invention provides for dynamically partitioning and un-partitioning a local store for the authentication of code or data. The local store is partitioned into an isolated and non-isolated section. Code or data is loaded into the isolated section. The code or data is authenticated in the isolated section of the local store. After authentication, the code is executed. After execution, the memory within the isolated region of the attached processor unit is erased, and the attached processor unit de-partitions the isolated section within the local store.

Abstract: An approach is provided to allow virtual devices that use a plurality of processors in a multiprocessor systems, such as the BE environment. Using this method, a synergistic processing unit (SPU) can either be dedicated to performing a particular function (i.e., audio, video, etc.) or a single SPU can be programmed to perform several functions on behalf of the other processors in the system. The application, preferably running in one of the primary (PU) processors, issues IOCTL commands through device drivers that correspond to SPUs. The kernel managing the primary processors responds by sending an appropriate message to the SPU that is performing the dedicated function. Using this method, an SPU can be virtualized for swapping multiple tasks or dedicated to performing a particular task.

Abstract: An approach that uses a handler to detect asynchronous lock line reservation lost events, and switching tasks based upon whether a condition is true or a mutex lock is acquired is presented. A synergistic processing unit (SPU) invokes a first thread and, during execution, the first thread requests external data that is shared with other threads or processors in the system. This shared data may be protected with a mutex lock or other shared memory synchronization constructs. When requested data is not available, the SPU switches to a second thread and monitors lock line reservation lost events in order to check when the data is available. When the data is available, the SPU switches back to the first thread and processes the first thread's request.

Abstract: The present invention provides for notifying threads. A determination is made whether there is a condition for which a thread is to be notified. If so, a notification indicia is broadcasted. A flag is set in at least one memory storage area as a function of the notification indicia wherein the setting the flag occurs without the intervention of an operating system. Therefore, latencies for notification of threads are minimized.

Abstract: A system and method for speculative assistance to a thread in a heterogeneous processing environment is provided. A first set of instructions is identified in a source code representation (e.g., a source code file) that is suitable for speculative execution. The identified set of instructions are analyzed to determine the processing requirements. Based on the analysis, a processor type is identified that will be used to execute the identified first set of instructions based. The processor type is selected from more than one processor types that are included in the heterogeneous processing environment. The heterogeneous processing environment includes more than one heterogeneous processing cores in a single silicon substrate. The various processing cores can utilize different instruction set architectures (ISAs). An object code representation is then generated for the identified first set of instructions with the object code representation being adapted to execute on the determined type of processor.

Abstract: Asynchronously traversing a disjoint linked data structure is presented. A synergistic processing unit (SPU) includes a handler that works in conjunction with a memory flow controller (MFC) to traverse a disjoint linked data structure. The handler compares a search value with a node value, and provides the MFC with an effective address of the next node to traverse based upon the comparison. In turn, the MFC retrieves the corresponding node data from system memory and stores the node data in the SPU's local storage area. The MFC stalls processing and sends an asynchronous event interrupt to the SPU which, as a result, instructs the handler to retrieve and compare the latest node data in the local storage area with the search value. The traversal continues until the handler matches the search value with a node value or until the handler determines a failed search.

Abstract: A computer system's multiple processors are managed as devices. The operating system accesses the multiple processors using processor device modules loaded into the operating system to facilitate a communication between an application requesting access to a processor and the processor. A device-like access is determined for accessing each one of the processors similar to device-like access for other devices in the system such as disk drives, printers, etc. An application seeking access to a processor issues device-oriented instructions for processing data, and in addition, the application provides the processor with the data to be processed. The processor processes the data according to the instructions provided by the application.

Abstract: An apparatus which uses channel counters in combination with channel count read instructions as a means of providing information that data in a given channel is valid or has not been previously read. The counter may also, in the situation of the channel being defined as blocking, be used to prevent the unintentional overwriting of data in a register used by the channel or, alternatively, prevent further communications with the device assigned to that channel when a given count occurs. Intelligent external devices may also use channel count read instructions sent to the counting mechanism for reading from and writing to the channel.

Abstract: The present invention provides for atomic update primitives in an asymmetric single-chip heterogeneous multiprocessor computer system having a shared memory with DMA transfers. At least one lock line command is generated from a set comprising a get lock line command with reservation, a put lock line conditional command, and a put lock line unconditional command.

Abstract: A system and method for an efficient implementation of a software-managed cache is presented. When an application thread executes on a simple processor, the application thread uses a conditional data select instruction for eliminating a conditional branch instruction when accessing a software-managed cache. An application thread issues a conditional data select instruction (DMA transfer) after a cache directory lookup, wherein the size of the requested data is dependent upon the outcome of the cache directory lookup. When the cache directory lookup results in a cache hit, the application thread requests a transfer of zero bits of data, which results in a DMA controller (DMAC) performing a no-op instruction. When the cache directory lookup results in a cache miss, the application thread requests a data block transfer the size of a corresponding cache line.

Abstract: Loading software on a plurality of processors is presented. A processing unit (PU) retrieves a file from system memory and loads it into its internal memory. The PU extracts a processor type from the file's header which identifies whether the file should execute on the PU or a synergistic processing unit (SPU). If an SPU should execute the file, the PU DMA's the file to the SPU for execution. In one embodiment, the file is a combined file which includes both PU and SPU code. In this embodiment, the PU identifies one or more section headers included in the file which indicates embedded SPU code within the combined file. In this embodiment, the PU extracts the SPU code from the combined file and DMA's the extracted code to an SPU for execution.

Abstract: The present invention provides a method and apparatus for creating memory barriers in a Direct Memory Access (DMA) device. A memory barrier command is received and a memory command is received. The memory command is executed based on the memory barrier command. A bus operation is initiated based on the memory barrier command. A bus operation acknowledgment is received based on the bus operation. The memory barrier command is executed based on the bus operation acknowledgment. In a particular aspect, memory barrier commands are direct memory access sync (dmasync) and direct memory access enforce in-order execution of input/output (dmaeieio) commands.

Abstract: A component of a microprocessor-based data processing system, which includes features for regulating power consumption in snoopable components and has gating off memory coherency properties, is determined to be in a relatively inactive state and is transitioned to a non-snoopable low power mode. Then, when a snoop request occurs, a retry protocol is sent in response to the snoop request. In conjunction with the retry protocol, a signal is sent to bring the component into snoopable mode. When the retry snoop is requested, the component is in full power mode and can properly respond to the snoop request. After the snoop request has been satisfied, the component again enters into a low power mode.

Abstract: Methods and apparatus provide for transferring a plurality of data blocks between a shared memory and a local memory of a processor in response to a single DMA command issued by the processor to a direct memory access controller (DMAC), wherein the processor is capable of operative communication with the shared memory and the DMAC is operatively coupled to the local memory.

Abstract: The present invention provides for an apparatus employed to debug a program operating in a supplemental processor when the processor's registers are not readable directly by the debugging operation of a main processor. A program operating in main memory halts due to operational errors. The program code lines save to a cache. In the main processor, a pool of memory is reserved. A copy of the data from the nominally inaccessible supplementary processor registers also transfers to the reserved storage area for processing of the program needing debugging. After the program debugging is complete, a copy of the contents of the memory pool is restored to the memory of the target supplemental processor. A copy of the local store register state and remaining local store data returns to main memory.

Abstract: Grouping processors is presented. A processing unit (PU) initiates an application and identifies the application's requirements. The PU assigns one or more synergistic processing units (SPUs) and a memory space to the application in the form of a group. The application specifies whether the task requires shared memory or private memory. Shared memory is a memory space that is accessible by the SPUs and the PU. Private memory, however, is a memory space that is only accessible by the SPUs that are included in the group. When the application executes, the resources within the group are allocated to the application's execution thread. Each group has its own group properties, such as address space, policies (i.e. real-time, FIFO, run-to-completion, etc.) and priority (i.e. low or high). These group properties are used during thread execution to determine which groups take precedence over other tasks.

Abstract: The present invention provides a mechanism for a processor to write data to a cache or other fast memory, without also writing it to main memory. Further, the data is “locked” into the cache or other fast memory until it is loaded for use. Data remains in the locking cache until it is specifically overwritten under software control. The locking cache or other fast memory can be used as additional system memory. In an embodiment of the invention, the locking cache is one or more sets of ways, but not all of the sets or ways, of a multiple set associative cache.

Abstract: The present invention provides a mechanism of storing data transferred from an I/O device, a network, or a disk into a portion of a cache or other fast memory, without also writing it to main memory. Further, the data is “locked” into the cache or other fast memory until it is loaded for use. Data remains in the locking cache until it is specifically overwritten under software control. In an embodiment of the invention, a processor can write data to the cache or other fast memory without also writing it to main memory. The portion of the cache or other fast memory can be used as additional system memory.

Abstract: To alleviate at least some of the costs associated with context switching, addition fields, either with associated Application Program Interfaces (APIs) or coupled to application modules, can be employed to indicate points of light weight context during the operation of an application. Therefore, an operating system can pre-empt applications at points where the context is relatively light, reducing the costs on both storage and bus usage.

Abstract: The present invention provides for a system comprising a DMA queue configured to receive a DMA command comprising a tag, wherein the tag belongs to one of a plurality of tag groups. A counter couples to the DMA queue and is configured to increment a tag group count of the tag group to which the tag belongs upon receipt of the DMA command by the DMA queue and to decrement the tag group count upon execution of the DMA command. A tag group count status register couples to the counter and is configured to store the tag group count for each of the plurality of tag groups. And the tag group count status register is further configured to receive a request for a tag group status and to respond to the request for the tag group status.