Abstract: A system may comprise a condition detection system that includes change circuitry configured to detect a change for at least one predetermined bit of an N-bit bus, where N is a positive integer, and to provide a corresponding change signal indicative of the detected condition. Match circuitry is configured to detect a match condition for up to a selected subset of predetermined bits of the N-bit bus and to provide a corresponding match signal indicative of the detected condition. Selection circuitry is programmable to provide a selected one of the change signal and the match signal as a corresponding output signal.

Abstract: A method of generating a timestamp includes measuring a time period between two events, automatically determining a precision for an indication of the time period, and storing the timestamp. The precision for the indication of the time period is decreased as the time period increases. The timestamp includes an indication of the precision and the indication of the time period, wherein the indication of the time period in the timestamp is stored according to the automatically determined precision.

Abstract: A circuit for tracking a number of clock cycles between occurrences of an event of interest. The circuit includes logic for asserting a run signal responsive to a first occurrence of the event of interest, logic for deasserting the run signal responsive to a second occurrence of the event of interest, and logic for incrementing a count value on each clock cycle while the run signal is asserted.

Abstract: A system may comprise a condition detection system that includes change circuitry configured to detect a change for at least one predetermined bit of an N-bit bus, where N is a positive integer, and to provide a corresponding change signal indicative of the detected condition. Match circuitry is configured to detect a match condition for up to a selected subset of predetermined bits of the N-bit bus and to provide a corresponding match signal indicative of the detected condition. Selection circuitry is programmable to provide a selected one of the change signal and the match signal as a corresponding output signal.

Abstract: A circuit for tracking the minimum and maximum duration of an event of interest, and for tracking the minimum and maximum value of a signal of interest, is described. The circuit is connected to a counter for counting a number of clock cycles that the event of interest is active and comprises logic for detecting deactivation of the event of interest and generating a duration end signal; logic responsive to the duration end signal for capturing a value of the counter as a count value in a first circuit configuration, logic for capturing the value of the signal of interest as the count value in a second circuit configuration, logic for comparing the count value with a shadow value; and logic for updating the shadow value based on results of the comparing.

Abstract: A circuit for tracking a number of clock cycles between occurrences of an event of interest is described. The circuit comprises logic for asserting a run signal responsive to a first occurrence of the event of interest; logic for deasserting the run signal responsive to a second occurrence of the event of interest; and logic for incrementing a count value on each clock cycle while the run signal is asserted.

Abstract: A method of generating a timestamp includes measuring a time period between two events, automatically determining a precision for an indication of the time period, and storing the timestamp. The precision for the indication of the time period is decreased as the time period increases. The timestamp includes an indication of the precision and the indication of the time period, wherein the indication of the time period in the timestamp is stored according to the automatically determined precision.

Abstract: A method of operating a central cache controller (“CCC”) in a first cell of a multiprocessor system comprising multiple cells each including globally shared memory (“GSM”), wherein the first cell is disposed in a first partition and the CCC is connected to a plurality of CPUs of the first cell. In one embodiment, the method comprises, responsive to a new transaction request from one of the CPUs, logging the transaction in a transaction table; determining whether an identity marker in a timeout map corresponding to a cell to which the transaction was issued is set; and, responsive to the corresponding identity marker in the timeout map being set, immediately returning a special error to the one of the CPUs that requested the transaction.

Abstract: A computing device having partitions, and a method of communicating between partitions, are disclosed wherein at least one partition comprises: at least one register substantially always accessible to other partitions and capable of defining an address area; at least one address area that may be accessible to other partitions and is capable of being defined by the at least one register; and address areas other than the at least one accessible address area that are not accessible to other partitions. A method of processing interrupts comprising receiving an interrupt, assessing the origin of the interrupt, accepting, rejecting, or further assessing the interrupt, depending on its origin, when further assessing the interrupt, accepting or rejecting the interrupt depending on its contents, and forwarding accepted interrupts but not rejected interrupts to a target processor, and a device carrying out that method are also disclosed.

Abstract: A controller arrangement and method for effectuating data transfer between a first clock domain and a second clock domain. In one embodiment, inversion circuitry inverts a first clock signal associated with the first clock domain into an inverted first clock signal that is used in effectuating a SYNC pulse during coincident edges of the inverted first clock signal and a second clock signal associated with the second clock domain. Clock synchronizer controller circuitry operates responsive to sampled sync pulses based on the SYNC pulse to generate domain synchronizer control signals for effectuating data transfer between the first and second clock domains.

Abstract: A clock synchronizer for effectuating data transfer between first and second clock domains by utilizing first and second synchronizer controllers. The first synchronizer controller circuit operates in the first clock domain which has N first clock cycles and the second synchronizer controller circuit operates in the second clock domain which has M second clock cycles, wherein N/M?1. Inversion circuitry inverts a first clock signal associated with the first clock domain to generate an inverted first clock signal which is used in effectuating a SYNC pulse during coincident edges of the inverted first clock signal and a second clock signal associated with the second clock domain.

Abstract: A drift-tolerant sync generation circuit and sync generation method for a sync pulse generator operable in a clock synchronizer that effectuates data transfer between first circuitry disposed in a first clock domain and second circuitry disposed in a second clock domain. The first clock domain is operable with a first clock signal and the second clock domain is operable with a second clock signal. A sync circuit portion, responsive to a valid edge signal indicative of coincident edges between the first and second clock signals, is operable to generate based upon the ratio a start sync signal substantially centered around the coincident edges. A first sync generator, responsive to the start sync signal, is operable to generate synchronization pulses in the first clock domain. A second sync generator, responsive to the start sync signal, is operable to generate synchronization pulses in the second clock domain.

Abstract: A phase detector and phase detection method for a sync pulse generator operable in a clock synchronizer that effectuates data transfer between first circuitry disposed in a first clock domain and second circuitry disposed in a second clock domain. The first clock domain is operable with a first clock signal and the second clock domain is operable with a second clock signal. At least one first flip flop is operable to sample the first clock signal with a rising edge of the second clock signal and at least one second flip flop is operable to sample the first clock signal with a falling edge of the second clock signal. The sampling produces transitions indicative of the coincident rising edges between the first and second signals.

Abstract: A programmable sync pulse generator and sync pulse generation method are operable in a clock synchronizer to effectuate data transfer between first circuitry disposed in a first clock domain and second circuitry disposed in a second clock domain. The first clock domain is operable with a first clock signal and the second clock domain is operable with a second clock signal. A phase detection circuitry is operable to sample the first clock signal with the second clock signal to determine coincident edges of the first and second clock signals. Validation circuitry is operable to validate the coincident edges based upon skew tolerance between the first and second clock signals and to generate a valid edge signal responsive thereto. Sync generation circuitry, responsive to the valid edge signal, is operable to generate synchronization pulses in the first clock domain and synchronization pulses in the second clock domain.

Abstract: A system and method for observing the functional behavior of a target circuit. In one embodiment, a first interface, which is external with respect to the target circuit, is provided for generating behavioral definitions relative to the target circuit. A programmer module is used, responsive to the behavioral definitions, for generating a programmation file that manipulates a logic analyzer, which is embedded with respect to the target circuit. An observability tool is provided for utilizing the programmation file to observe the target circuit's functionality. A second interface, which is external with respect to the target circuit, displays results relative to observing the target circuit's functionality.

Abstract: A circuit for tracking the minimum and maximum duration of an event of interest is described. The circuit is connected to a counter for counting a number of clock cycles that the event of interest is active and comprises logic for detecting deactivation of the event of interest and generating a duration end signal; logic responsive to the duration end signal for comparing a count value with a shadow value; and logic for updating the shadow value based on results of the comparing.

Abstract: An edge detect circuit connected to a bus carrying data is described. In one embodiment, the edge detect circuit comprises logic for detecting an edge of a raw increment signal and logic for activating an increment signal upon detection of an edge of the raw increment signal.

Abstract: A system for validating data collected in a first clock domain. A performance counter is disposed in a second clock domain to perform performance computations relative to the data. Validation circuitry is in communication with the data in order to provide to the performance counter a validation signal indicative of the validity of the data.

Abstract: A match circuit connected to a bus carrying data is described. In one embodiment, the match circuit comprises logic for activating a match_mm signal when a selected N-bit portion of the data matches an N-bit threshold for all bits selected by an N-bit match mask (“mmask”) and logic for activating a match_OR signal when at least one of one or more designated bits of the selected N-bit portion of the data is a logic 1 or if there are no designated bits.

Abstract: Transactions are received through at least two input channels, each transaction comprising one or more data packets. The data packets are placed in a single data queue. When a first transaction received through one input channel comprises more than one data packet, a data packet of a second transaction received through another input channel is permitted to be placed in the single data queue between data packets of the first transaction. A block of space in a data output queue is assigned to each transaction. Each data packet is placed in the block assigned to its transaction.