Intel Corporation

Micron Technology Incorporated

Marvell International Limited

Stephen J Strazdus

Dennis M O'Connor

Michael W Morrow

Lawrence T Clark

Mark Norman Fullerton

Nigel C Paver

Byron R Gillespie

Jay S Heeb

Dan Wheeler Patterson

Mukesh Patel

Murli Ganeshan

Thomas M Johnson

Wing K Yu

William T Maghielse

Jianwei Liu

Rupal Parikh

Richard Brunner

Anthony Jebson

Paul G Meyer

Aravindh Bakthavathsalu

Thomas Adelmeyer

Deli Deng

Eliot Garbus

Avery Topps

Kailesh B Bavaria

Two translation lookaside buffers may be provided for simpler operation in some embodiments. A hardware managed lookaside buffer may handle traditional operations. A software managed lookaside buffer may be particularly involved in locking particular translations. As a result, the software's job is made simpler since it has a relatively simpler, software managed translation lookaside buffer to manage for locking translations.

Locking entries into translation lookaside buffers

A processor includes a multi-level cache hierarchy where a lock property is associated with a cache line. The cache line retains the lock property and may move back and forth within the cache hierarchy. The cache line may be evicted from the cache hierarchy after the lock property is removed.

Moveable locked lines in a multi-level cache

A method includes indexing a translation table stored in memory with a first index of a virtual address corresponding to a first memory region size by querying the translation table at first locations associated with the first index. Indexing the translation table with a second index of the virtual address corresponding to a second memory region size by querying the translation table at second locations associated with the second index. The translation table includes translations for mapping address tags of the virtual address to physical addresses. The first index is different than the second index, and the first memory region size is different than the second memory region size.

Serially indexing a cache memory

In one embodiment, the present invention includes a method of accessing a cache memory to determine whether requested data is present. In this embodiment, the method may include indexing a cache with a first index corresponding to a first memory region size, and indexing the cache with a second index corresponding to a second memory region size. The second index may be used if the requested data is not found using the first index.

A two-stage arbiter system comprises a first-stage arbiter to grant a request to one of a plurality of requestors in accordance with a first arbitration scheme and a second-stage arbiter to grant one of the remaining requests in accordance with a second arbitration scheme. The first arbitration scheme may be a fast arbitration scheme such as a fixed-priority scheme, and the second arbitration scheme may be a rotating priority-based arbitration scheme or a least-recently-granted arbitration scheme. The first-stage arbiter may operate in a first pipelined stage, and the second-stage arbiter may operate in a second pipelined stage. Two-stage arbitration may help improve access of lower-priority requestors in a pipelined system. In one embodiment, a rotating-priority arbitrator includes a pseudo-random number generator to generate an amount for rotating priorities prior to arbitration. The rotating-priority arbiter may use either a counter or linear-feedback shift register to rotate priorities of requests.

High-speed starvation-free arbiter system, rotating-priority arbiter, and two stage arbitration method

A processor-based system may include a main processor and a coprocessor. The coprocessor handles instructions that include opcodes specifying a data processing operation to be performed by the coprocessor and a coprocessor identification field for identifying a target coprocessor for coprocessor instructions. Two bits indicate one of four data sizes including a byte (8 bits), a half word (16 bits), a word (32 bits), and a double word (64 bits). Two other bits indicate a saturation type.

Conditional execution of coprocessor instruction based on main processor arithmetic flags

A processor system having cache array for storing virtual tag information and physical tag information and corresponding comparators associated with the array to determine cache-hits. Information from the virtual tag array and the physical tag array may be accessed together.

Snoopy virtual level 1 cache tag

An apparatus and a system may include a modal property indicator and an access module to receive the modal property indicator and to access a selected location based on a condition of the modal property indicator. An article may include data, which, when accessed, results in a machine performing a method including indicating a processor mode to a memory including a plurality of instructions and predecoding an instruction selected from the plurality of instructions according to the processor mode.

Predecode apparatus, systems, and methods

A memory management unit (MMU) includes a translation look-aside buffer (TLB) that stores memory access steering data within corresponding TLB entries for use in steering memory access operations.

Method and apparatus to steer memory access operations in a virtual memory system

A processor core suitable for use with a wide variety of instruction fetch units. The processor core contains a plurality of pipe stages including an instruction pointer generation stage and a decode stage. The core bundles all control necessary for downstream pipeline operation with an instruction address in a first stage. The bundle is transmitted outside the core to the instruction fetch unit. The instruction fetch unit fetches the instruction and adds it to the bundle, before forwarding the bundle as modified back within the core and down the pipeline. In this way, an external pipe stage is introduced providing a connection between discontinuous pipe stages in the core. Additionally, by bundling the control signals and address information in a single bundle that traverses the external pipe stage as a group, synchronization concerns are reduced or eliminated.

Method and apparatus permitting the use of a pipe stage having an

A microprocessor system utilizing an in-circuit emulator (ICE) to aid in testing and debugging by an external emulator. The microprocessor operates in two modes. One mode is emulation mode in which the microprocessor outputs trace information for allowing the emulator to reconstruct microprocessor execution, and the other mode is interrogation mode where the microprocessor ceases emulation mode, and allows the emulator to modify the state of the microprocessor or interrogate it. An ICEBRK signal is provided on the microprocessor to better handle transition from emulation to interrogation mode. An address mark counter and generator is provided to force the microprocessor to automatically issue an address mark message which includes the location of the microprocessor's instruction pointer. An AMCTRL bit may be further provided to allow a human user to selectively inhibit the issuance of an address mark. An ICELOCK signal is provided on the microprocessor to control the writing of control registers during hardware and software initialization that the microprocessor performs. A MSGFRM signal is provided to aid the emulator in capturing trace information generated at high frequencies (in excess of 40 MHz).

Growing community of inventors

Chandler, AZ, United States of America

Stephen J Strazdus