International Business Machines Corporation

David Wallach

Anthony Correale, Jr

Ruchir Puri

William Robert Lee

David Shing-Ki Kung

Zhigang Pan

Douglass T Lamb

Eric M Foster

Stefan P Jackowski

Dennis E Franklin

An integrated circuit (IC) design, method and program product for reducing IC design power consumption. The IC is organized in circuit rows. Circuit rows may include a low voltage island powered by a low voltage (V) supply and a high voltage island powered by a high voltage (V) supply. Circuit elements including cells, latches and macros are placed with high or low voltage islands to minimize IC power while maintaining overall performance. Level converters may be placed with high voltage circuit elements.

Multiple voltage integrated circuit and design method therefor

A cross-bar switch which includes a plurality of master bus ports, the master bus ports adapted to receive a plurality of master buses; a plurality of slave bus ports, the slave bus ports adapted to receive a plurality of slave buses; a switching mechanism for selectively coupling the plurality of master bus ports to the plurality of slave bus ports; and a configuration mechanism for locking at least one of the plurality of slave buses in response to a transfer request initiated by a master device attached to one of the plurality of master buses. The cross-bar switch has the capability of selectively locking slave buses during a bus lock transfer. In the preferred embodiment, the configuration mechanism is a Bus Lock Bit on Configuration Registers on the cross-bar switch. The Bus Lock Bit is programmable through the Device Control Register bus, which allows the cross-bar switch to be dynamically programmable and changed by a processor in a larger system. The cross-bar switch minimizes the cycle latency between data transfers. This improves the bandwidth and throughput on the on-chip bus.

Dynamic bus locking in a cross bar switch

The present invention provides a cross-bar switch which includes a plurality of master bus ports, the master bus ports adapted to receive a plurality of master buses; a plurality of slave bus ports, the slave bus ports adapted to receive a plurality of slave buses; a manner of switching for selectively coupling the plurality of master bus ports to the plurality of slave bus ports; and a manner of configuration for prioritizing access requests by the plurality of master buses to the plurality of slave buses via the switching means. The cross-bar switch of the present invention has the capability of prioritizing requests between multiple parallel high speed buses. In a preferred embodiment, this arbitration is accomplished through Configuration Registers on the cross-bar switch. The Configuration Registers are programmable through the Device Control Register bus, which allows the cross-bar switch to be dynamically programmed and changed by a processor in a larger system. The cross-bar switch of the present invention minimizes the latency between data transfers. This improves the bandwidth and throughput on the on-chip bus.

Low latency data path in a cross-bar switch providing dynamically prioritized bus arbitration

A multi-path access control device for an integrated system is presented which allows simultaneous access to multiple external devices coupled thereto by multiple functional units. The multiple functional units are coupled to the shared access control device across two or more high speed, shared data buses. The control device includes multiple bus ports, each coupled to a different data bus, and a non-blocking crossbar switch coupled to the bus ports for controlling forwarding, with zero cycle latency, of requests from the functional units. Multiple external device ports are coupled to the non-blocking crossbar switch for receiving requests forwarded by the crossbar switch, and each external device is coupled to a different external device port. The crossbar switch allows multiple requests at the bus ports directed to different external devices to be forwarded to different external device ports for simultaneous accessing of different external devices coupled thereto pursuant to the multiple requests.

Growing community of inventors

Raleigh, NC, United States of America

David Wallach