Abstract: A method for broadcasting instructions/data to a plurality of processors in a multiprocessor device via aliasing is provided. In order to broadcast data to a plurality of processors, a control processor writes to the registers that store the identifiers of the processors and sets two or more of these registers to a same value. The control processor may write the desired data/instructions to be broadcast to a portion of memory corresponding to the starting address associated with the processor identifier of the two or more processors. When the two or more processors look for a starting address of their local store from which to read, the two or more processors will identify the same starting address, essentially aliasing the memory region. The two or more processors will read the instructions/data from the same aliased memory region starting at the identified starting address and process the same instructions/data.

Abstract: A method to efficiently pre-fetch and batch compiler-assisted software cache accesses is provided. The method reduces the overhead associated with software cache directory accesses. With the method, the local memory address of the cache line that stores the pre-fetched data is itself cached, such as in a register or well known location in local memory, so that a later data access does not need to perform address translation and software cache operations and can instead access the data directly from the software cache using the cached local memory address. This saves processor cycles that would otherwise be required to perform the address translation a second time when the data is to be used. Moreover, the system and method directly enable software cache accesses to be effectively decoupled from address translation in order to increase the overlap between computation and communication.

Abstract: A method for controlling asynchronous clock domains to perform synchronous operations is provided. With the method, when a synchronous operation is to be performed on a chip, the latches of the functional elements of the chip are controlled by a synchronous clock so that the latches are controlled synchronously even across asynchronous boundaries of the chip. The synchronous operation may then be performed and the chip's functional elements returned to being controlled by a local clock in an asynchronous manner after completion of the synchronous operation. This synchronous operation may be, for example, a power on reset (POR) operation, a manufacturing test sequence, debug operation, or the like.

Abstract: A method for encryption and decryption of data items is provided by defining a cipher key based on variables in a Chaotic Equation. The method includes selecting a Chaotic Equation from a set of Chaotic Equations, defining starting conditions of the variables of the equation, and applying the equation to each data item. The real and imaginary parts of the result of the iteration of the Chaotic Equation are combined with the data item by an arithmetic operation, for example, an XOR operation. Data items in a continuous stream with a rate dependency can be encrypted and decrypted on an item by item basis. The input or cipher key changes for each byte of the data encryption. Blocks of data can be encrypted using the method with an identifier of the order of the blocks in the data stream. If blocks are received out of sequence, the identifiers can be used to maintain the correct decryption order. The method of encryption and decryption can be used in devices to avoid the need for a session key.

Abstract: Mechanisms for asynchronous clock modeling in an integrated circuit simulation are provided. The mechanisms of the illustrative embodiments provide clock skewing logic for phase shifting a clock signal in an integrated circuit design. This clock skewing logic adds delay to one or more clocks of an integrated circuit design to thereby place that clock out of phase with other clocks in the integrated circuit design. In one illustrative embodiment, delay is introduced into a clock net in an increasing manner with each enablement of the clock skewing logic. In another illustrative embodiment, the introduced delay is increased and decreased within a window from no phase shift of the clock net up to a maximum phase shift of the clock net. Once the maximum phase shift is reached, the amount of delay introduced is decreased with subsequent enablement of the clock skewing logic.

Abstract: Mechanisms for modeling metastability decay through latches in an integrated circuit model are provided. Asynchronous clock boundaries are identified in the integrated circuit model and latches in a receive clock domain are enumerated. Latches within a range of the asynchronous clock boundary are selected for transformation. These latches are transformed into metastability decay latches using new latch primitive logic that models the decay of an indeterminate value. The metastability decay latches maintains an indeterminate value during a metastability time period and achieve a randomly selected logic value at the end of the metastability time period. The transformed integrated circuit model may then be simulated and the results analyzed to generate reports of the integrated circuit model's operation. The transformed integrate circuit model more accurately represents the actual operation of the hardware implementation of the integrated circuit model.

Abstract: In remote control systems (as in many other circumstances) the color representation of a bitmap is one of the heaviest factor in term of storage occupation and speed of transmission. Often, only a limited number of colors is actually used by a bitmap, so that the bit pattern of the single pixels is bigger than what is really needed to represent all the possible different colors. With the present invention, in case the number of colors does not exceed a predetermined thresholds, a palette table containing all the colors used in the bitmap is created. The pixel representations in the bitmap are then replaced by a pointer to the corresponding entry in the palette table. This allows to reduce the total size of the bitmap. The reduced bitmap is then transmitted together with the associated palette table. The receiving computer (the controller in a remote control system) is able to rebuild the original bitmap with the help of the palette table.

Abstract: A method for testing functional boundary logic at an asynchronous clock boundary of an integrated circuit device is provided. With the method, each clock domain has its own scan paths that do not cross domain boundaries. By eliminating the scanning across the boundaries, the requirement to have two clock grids in the asynchronously clocked domains may be eliminated. As a result, circuit area and design time with regard to the clock distribution design are reduced. In addition, removing the second clock grid, i.e. the high speed core or system clock, in the asynchronously clocked domains removes the requirement to have a multiplexing scheme for selection of clocking signals in the asynchronous domain. In addition to the above, the system and method provide boundary built-in-self-test logic for testing the functional crossing logic of boundaries between the clock domains in a functional mode of operation.

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: A method for preparing a first multimedia stream, for use with an environment comprising a repository for storing a plurality of tracks. Each track may be associated with at least one second multimedia stream. A track may comprise a single type of data (e.g., audio, video, etc.). The method may comprise receiving a request comprising an associated parameter (e.g.,a position parameter)and determining at least two of the plurality of tracks associated with the parameter. The at least two tracks may have associated information that matches the position parameter. Responsive to the determining the at least two tracks, the determined at least two tracks may be collated in order to generate the first multimedia stream.

Abstract: A system and method for test generation for system level verification using parallel algorithms are provided. The present invention generates test patterns for system level tests by exploiting the scalability of parallel algorithms while allowing for data set coloring and expected result checking. Based on the characteristics of the system being tested an iterative parallel algorithm is selected from a plurality of possible parallel algorithms. The selected parallel algorithm is then separated into separate program statements for execution by a plurality of processors. A serial version of the selected algorithm is executed to generate a set of expected results. The devised parallel version of the selected algorithm is then run to generate a set of test result data which is compared to the set of expected results. If the two sets of data match, it is determined that the system is operating correctly.

Abstract: A method is provided for accessing, by an application running on a first processor, operating system services from an operating system running on a second processor by performing an assisted call. A data plane processor first constructs a parameter area based on the input and output parameters for the function that requires control processor assistance. The current values for the input parameters are copied into the parameter area. An assisted call message is generated based on a combination of a pointer to the parameter area and a specific library function opcode for the library function that is being called. The assisted call message is placed into the processor's stack immediately following a stop-and-signal instruction. The control plane processor is signaled to perform the library function corresponding to the opcode on behalf of the data plane processor by executing a stop and signal instruction.

Abstract: A write-through cache scheme is created. A store data command is sent to a cache line of a cache array from a processing unit. It is then determined whether the address of the store data is valid, wherein the original data from the store's address has been previously loaded into the cache. A write-through command is sent to a system bus as a function of whether the address of the store data is valid. The bus controller is employed to sense the write-through command. If the write-through command is sensed, a clean command is generated by the bus controller. If the write-through command is sensed, the store data is written into the cache array, and the data is marked as modified. If the write-through command is sensed, the clean command is sent onto the system bus by the bus controller, thereby causing modified data to be written to memory.

Abstract: A mechanism for reducing the amount of power or energy consumed by an SRAM array when the SRAM array is being accessed is provided. Logic is provided that identifies a polarity of a row of memory cells whose data values are to be read. The polarity of the row of memory cells indicates whether a majority of the data values stored in the row of memory cells are logic 1 data values or logic 0 data values. Based on the polarity, selection logic either selects true data values or complement data values of the memory cells. Additional logic is provided in each memory cell for outputting a true data value to a read bit line and outputting a compliment data value to the read bit line based on the polarity.

Abstract: A method that enables application instances to pass block mode storage requests directly to a physical I/O adapter without run-time involvement from the local operating system or hypervisor is provided. In one aspect of the method, a mechanism is provided for handling user space creation and deletion operations for creating and deleting allocations of linear block addresses of a physical storage device to application instances. For creation, it is determined if there are sufficient available resources for creation of the allocation. For deletion, it is determined if there are any I/O transactions active on the allocation before performing the deletion. Allocation may be performed only if there are sufficient available resources and deletion may be performed only if there are no active I/O transactions on the allocation being deleted.

Abstract: Mechanisms for handling data cache misses out-of-order for asynchronous pipelines are provided. The mechanisms associate load tag (LTAG) identifiers with the load instructions and uses them to track the load instruction across multiple pipelines as an index into a load table data structure of a load target buffer. The load table is used to manage cache “hits” and “misses” and to aid in the recycling of data from the L2 cache. With cache misses, the LTAG indexed load table permits load data to recycle from the L2 cache in any order. When the load instruction issues and sees its corresponding entry in the load table marked as a “miss,” the effects of issuance of the load instruction are canceled and the load instruction is stored in the load table for future reissuing to the instruction pipeline when the required data is recycled.

Abstract: Mechanisms for performing useful computations during a software cache reload operation are provided. With the illustrative embodiments, in order to perform software caching, a compiler takes original source code, and while compiling the source code, inserts explicit cache lookup instructions into appropriate portions of the source code where cacheable variables are referenced. In addition, the compiler inserts a cache miss handler routine that is used to branch execution of the code to a cache miss handler if the cache lookup instructions result in a cache miss. The cache miss handler, prior to performing a wait operation for waiting for the data to be retrieved from the backing store, branches execution to an independent subroutine identified by a compiler. The independent subroutine is executed while the data is being retrieved from the backing store such that useful work is performed.

Abstract: A program written in untrusted code (e.g., JAVA) is enabled to access a native operating system resource (e.g., supported in WINDOWS NT) through a staged login protocol. In operation, a trusted login service listens, e.g., on a named pipe, for requests for login credentials. In response to a login request, the trusted login service requests a native operating system identifier. The native operating system identifier is then sent to the program. Using this identifier, a credential object is then created within an authentication framework. The credential object is then used to login to the native operating system to enable the program to access the resource. This technique enables a JAVA program to access a WINDOWS NT operating system resource under the identity of the user running the JAVA program.

Abstract: A system and method for sorting processor chips based on a thermal design point are provided. With the system and method, for each processor chip, a high power workload is run on the processor chip to determine a voltage regulator module (VRM) load line. Thereafter, a thermal design point (TDP) workload is applied to the processor chip and the voltage is varied until a performance of the processor chip falls on the VRM load line. At this point, the power input to the processor chip is measured and used to sort, or bin, the processor chip. The various workloads applied have a constant frequency. From this sorting of processor chips, high speed processors that require less voltage to achieve a desired frequency and low current processors that drain less current while running at a desired frequency may be identified.

Abstract: The present invention allows a microprocessor to identify and speculatively execute future load instructions during a stall condition. This allows forward progress to be made through the instruction stream during the stall condition which would otherwise cause the microprocessor or thread of execution to be idle. The data for such future load instructions can be prefetched from a distant cache or main memory such that when the load instruction is re-executed (non speculative executed) after the stall condition expires, its data will reside either in the L1 cache, or will be enroute to the processor, resulting in a reduced execution latency. When an extended stall condition is detected, load lookahead prefetch is started allowing speculative execution of instructions that would normally have been stalled.