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.

Abstract: A method 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 1ocal 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 secure communication methodology is presented. The client device is configured to download application code and/or content data from a server operated by a service provider. Embedded within the client is a client private key, a client serial number, and a copy of a server public key. The client forms a request, which includes the client serial number, encrypts the request with the server public key, and sends the download request to the server. The server decrypts the request with the server's private key and authenticates the client. The received client serial number is used to search for a client public key that corresponds to the embedded client private key. The server encrypts its response, which includes the requested information, with the client public key of the requesting client, and only the private key in the requesting client can be used to decrypt the information downloaded from the server.

Abstract: A computer architecture and programming model for high speed processing over broadband networks are provided. The architecture employs a consistent modular structure, a common computing module and uniform software cells. The common computing module includes a control processor, a plurality of processing units, a plurality of local memories from which the processing units process programs, a direct memory access controller and a shared main memory. A synchronized system and method for the coordinated reading and writing of data to and from the shared main memory by the processing units also are provided. A hardware sandbox structure is provided for security against the corruption of data among the programs being processed by the processing units. The uniform software cells contain both data and applications and are structured for processing by any of the processors of the network. Each software cell is uniquely identified on the network.

Abstract: A design structure for a processor system may be embodied in a machine readable medium for designing, manufacturing or testing a processor integrated circuit. The design structure may embody a processor system that integrates error correcting code (ECC) detection and correction hardware within an memory management circuit. The design structure may specify ECC hardware circuitry that provides detection, correction and generation of ECC data bits in conjunction with memory data read and writes. The design structure for the processor system may permit the detection and correction of soft single bit errors read from local memory in-line while using read modify write DMA circuit logic to correct local memory data. The design structure may provide for local memory data error detection and correction in a background memory scrub process without the need for additional in-line data logic.

Abstract: A computer architecture and programming model for high speed processing over broadband networks are provided. The architecture employs a consistent modular structure, a common computing module and uniform software cells. The common computing module includes a control processor, a plurality of processing units, a plurality of local memories from which the processing units process programs, a direct memory access controller and a shared main memory. A synchronized system and method for the coordinated reading and writing of data to and from the shared main memory by the processing units also are provided. A hardware sandbox structure is provided for security against the corruption of data among the programs being processed by the processing units. The uniform software cells contain both data and applications and are structured for processing by any of the processors of the network. Each software cell is uniquely identified on the network.

Abstract: A method and apparatus for adding and multiplying floating-point operands such that a fixed-size mantissa result is produced. In accordance with the present addition method, the mantissa of a first floating-point operand is shifted in accordance with relative operand exponent information. Next, the first operand mantissa is added to the second operand mantissa. The addition step includes replacing a least significant non-overlapped portion of the first operand mantissa with a randomly-generated carry-in bit. In accordance with the multiplication method, a partial product array is generated from a pair of floating-point operand mantissas. Next, prior to compressing the partial product array into a compressed mantissa result, a lower-order bit portion of the partial product array is replaced with a randomly generated carry-in value.

Abstract: Given a function F of a circuit having a data latching device and a feedback loop feeding an output Q of the device into logic which feeds the device, a method includes extracting at least one data independent case and clock-gating the device with the at least one data independent case. The method also includes eliminating the feedback loop if function F depends only on Q with a positive polarity or leaving the feedback loop if function F depends on Q in both positive and negative polarities.

Abstract: A method for controlling rounding modes in a single instruction multiple data (SIMD) floating-point unit is disclosed. The SIMD floating-point unit includes a floating-point status-and-control register (FPSCR) having a first rounding mode bit field and a second rounding mode bit field. The SIMD floating-point unit also includes means for generating a first slice and a second slice. During a floating-point operation, the SIMD floating-point unit concurrently performs a first rounding operation on the first slice and a second rounding operation on the second slice according to a bit in the first rounding mode bit field and a bit in the second rounding mode bit field within the FPSCR, respectively.

Abstract: A system and method are provided to dedicate one or more processors in a multiprocessing system to performing encryption functions. When the system initializes, one of the synergistic processing unit (SPU) processors is configured to run in a secure mode wherein the local memory included with the dedicated SPU is not shared with the other processors. One or more encryption keys are stored in the local memory during initialization. During initialization, the SPUs receive nonvolatile data, such as the encryption keys, from nonvolatile register space. This information is made available to the SPU during initialization before the SPUs local storage might be mapped to a common memory map. In one embodiment, the mapping is performed by another processing unit (PU) that maps the shared SPUs' local storage to a common memory map.

Abstract: Systems and methods for adaptively mapping system memory address bits into an instruction tag and an index into the cache are disclosed. More particularly, hardware and software are disclosed for observing collisions that occur for a given mapping of system memory bits into a tag and an index. Based on the observations, an optimal mapping may be determined that minimizes collisions.

Abstract: A processor system executes multiple applet programs within a software application program in an information handling system. The information handling system includes operating system software that manages processor system hardware and software in a multi-tasking environment. In particular, the operating system software manages partitioning of a register file in the processor system to achieve a cooperative relationship among multiple applet programs within respective partitions of the register file. In one embodiment, the operating system software manages unique applet ID's to modify register file partition sizes and locations during applet program instruction text execution. In one embodiment, applet ID masking hardware provides sharing of register file space among multiple copies of applet program code.

Abstract: In a first aspect, a first method is provided that includes providing a plurality of select signals and a plurality of input signals for input by a multiplexer. Each select signal is adapted to cause the multiplexer to select a different one of the plurality of input signals for output by the multiplexer when the select signal is in a first logic state. The first method further includes preventing a first of the select signals that is in the first logic state from being provided to the multiplexer until the other select signals are in a second logic state. Number other aspects are provided.

Abstract: An apparatus for controlling rounding modes in a single instruction multiple data (SIMD) floating-point unit is disclosed. The SIMD floating-point unit includes a floating-point status-and-control register (FPSCR) having a first rounding mode bit field and a second rounding mode bit field. The SIMD floating-point unit also includes means for generating a first slice and a second slice. During a floating-point operation, the SIMD floating-point unit concurrently performs a first rounding operation on the first slice and a second rounding operation on the second slice according to a bit in the first rounding mode bit field and a bit in the second rounding mode bit field within the FPSCR, respectively.

Abstract: High-precision floating-point function estimates are split in two instructions each: a low precision table lookup instruction and a linear interpolation instruction. Estimates of different functions can be implemented using this scheme: A separate table-lookup instruction is provided for each different function, while only a single interpolation instruction is needed, since the single interpolation instruction can perform the interpolation step for any of the functions to be estimated. Thus, significantly less overhead is incurred than would be incurred with specialized hardware, while still maintaining a uniform FPU latency, which allows for much simpler control logic.

Abstract: A computer architecture and programming model for high speed processing over broadband networks are provided. The architecture employs a consistent modular structure, a common computing module and uniform software cells. The common computing module includes a control processor, a plurality of processing units, a plurality of local memories from which the processing units process programs, a direct memory access controller and a shared main memory. A synchronized system and method for the coordinated reading and writing of data to and from the shared main memory by the processing units also are provided. A hardware sandbox structure is provided for security against the corruption of data among the programs being processed by the processing units. The uniform software cells contain both data and applications and are structured for processing by any of the processors of the network. Each software cell is uniquely identified on the network.

Abstract: A program is into at least two object files: one object file for each of the supported processor environments. During compilation, code characteristics, such as data locality, computational intensity, and data parallelism, are analyzed and recorded in the object file. During run time, the code characteristics are combined with runtime considerations, such as the current load on the processors and the size of the data being processed, to arrive at an overall value. The overall value is then used to determine which of the processors will be assigned the task. The values are assigned based on the characteristics of the various processors. For example, if one processor is better at handling intensive computations against large streams of data, programs that are highly computationally intensive and process large quantities of data are weighted in favor of that processor. The corresponding object is then loaded and executed on the assigned processor.

Abstract: Disclosed is a procedure or design approach for functional modules that may be used in connection with a multiprocessor integrated circuit chip. The approach includes keeping the dimensions of each module substantially the same and having the bus, power, clock and I/O connection configured the same on all modules. Further requirements for ease of use are to generalize the capability of each module as much as possible and to decentralize functions such as testing to be primarily performed within each module. The use of such considerations or rules substantially eases the design of a given type of custom chips, and based upon an initial chip design greatly facilitates the design of further custom chips, similar in application, but subsequent to the successful completion of the initial chip.

Abstract: Systems and methods for distributing thread instructions in the pipeline of a multi-threading digital processor are disclosed. More particularly, hardware and software are disclosed for successively selecting threads in an ordered sequence for execution in the processor pipeline. If a thread to be selected cannot execute, then a complementary thread is selected for execution.

Abstract: An apparatus is provided for using multiple thread contexts to improve processing performance of a single thread. When an exceptional instruction is encountered, the exceptional instruction and any predicted instructions are reloaded into a buffer of a first thread context. A state of the register file at the time of encountering the exceptional instruction is maintained in a register file of the first thread context. The instructions in the pipeline are executed speculatively using a second register file in a second thread context. During speculative execution, cache misses may cause loading of data to the cache may be performed. Results of the speculative execution are written to the second register file. When a stopping condition is met, contents of the first register file are copied to the second register file and the reloaded instructions are released to the execution pipeline.