Canon Kabushiki Kaisha

Canon Information Systems Research Australia Pty. Ltd.

Christopher Amies

Timothy Merrick Long

Ian Richard Gibson

Michael John Webb

Graham Stoney

A graphics processor performs graphical operations on graphical objects represented in an external data format. The graphics processor includes a setup unit, first and second mapping units, and a calculator. The setup unit sets up one or more registers reflecting a current instruction. The first mapping unit maps, responsive to the current instruction, the external data format to at least one corresponding internal data format selected from a set of internal data formats. The calculator performs graphical operations on the graphical objects when in one of the selected internal data formats. The second mapping unit maps, responsive to the current instruction, each internal data format in the set of internal data formats to the external data format after the graphical operations have been performed.

Data normalization technique

The present invention discloses apparatus for, and a method of, rendering image data prior to outputting of the resulting image. A graphics co-processor ( ) is utilized together with a host CPU ( ), the former having a plurality of data calculation streams ( ) arranged in parallel fashion. Only one of the data calculation streams ( ) is operated at any one time. Preferably at least one ( ) of the data calculation streams is able to be reconfigured.

Multi-instruction stream processor

The present invention relates to a method, apparatus and system for managing virtual memory, in which a co-processor ( ) is adapted to use virtual memory with a host processor ( ). A host memory ( ) is coupled to the host processor ( ) to implement the virtual memory. The co-processor ( ) includes a virtual-physical memory mapping device ( ) for interrogating a virtual memory table and for mapping one or more virtual memory addresses ( ) requested by the co-processor ( ) into corresponding physical addresses ( ) in the host memory ( ). The virtual memory table is stored in two or more non-contiguously addressable regions of the host memory ( ), and is preferably a page table. The memory mapping device ( ) further includes a multiple-entry translation lookaside buffer ( ) for caching virtual-to-physical address mappings ( ), where entries in the buffer ( ) are replaced on a least recently used replacement basis. The memory mapping device ( ) also includes devices ( ) for comparing, replacing, singly invalidating and multiply invalidating one or more entries of the translation lookaside buffer ( ). It also includes a hashing device ( ) for, upon an occurrence of a miss in the translation lookaside buffer ( ), hashing a virtual memory address ( ) using a hash function to produce an index into the virtual memory table.

Method apparatus and system for managing virtual memory with virtual-physical mapping

The present invention discloses an image processor ( ) for executing a computer instruction set ( ) in the form of an opcode ( ), at least one operand ( ) which is, or indicates the location of data to be processed. The data to be processed consists of a variable length stream of data and each instruction includes a length field ( ) containing data specifying the number of items of data to be processed or, if that number exceeds the size of the length field, a predetermined location of a previously allocated storage area at which that number is stored.

System for executing instructions having flag for indicating direct or indirect specification of a length of operand data

Method, apparatus and system for managing virtual memory with virtual-physical mapping

A graphics processor for performing graphical operations on graphical objects that are represented in an external data format selected from a set thereof includes a first mapping unit adapted to map one or more groups of different ones of the set of external data formats to corresponding one or more internal data formats selected from a set of internal data formats, a calculator for performing graphical operations on the graphical objects when in the one or more internal data formats, and a second mapping unit adapted to map each internal data format in the set of internal data formats to an external data format selected from the set of external data formats after the graphical operations have been performed.

Data normalization techniques

A method of updating, directing or moving page table entry values in a virtual memory management system. The method operates without requiring suspension of a search process looking for a predetermined page table entry value of a page table. In a first step, the method determines whether the current page table value is the predetermined page table entry value or whether the search process looking for a page table entry value is in progress. Then, the current page table entry value is deleted or moved in the event that the current page table entry value is not the predetermined page table entry value or in the event that the search process is not in progress. Next, the method waits until the search process has completed looking for the predetermined page table entry value or for a predetermined period of time before deleting or moving the current page table entry value, in the event that the current page table entry value is the predetermined page table entry value or in the event that the search process looking for a page table entry value is in progress.

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Wilston, Australia

Christopher Amies