The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 17, 1998
Filed:
Sep. 05, 1995
Joseph Anthony Petolino, Jr, Palo Alto, CA (US);
Sun Microsystems, Inc., Mountain View, CA (US);
Abstract
The present invention provides for a method and apparatus for reading non-cachable information in a cache memory system. The cache memory system includes a processor, a buffer, a multiplexor, main memory, an input/output unit, a cache controller, a memory management unit, and cache memory. In a read operation, the processor directs a read operation specifying a first address to the cache memory. The cache controller initially determines whether the information desired is cachable or non-cachable. If the information desired is determined to be non-cachable, the cache controller causes any information presently contained in a first location in the cache memory to be stored in the buffer. In the interim, the cache controller causes the memory management unit to initiate an access of the information desired from the first address. Once accessed, this information is temporarily written into the first location within the cache memory. From this first location within the cache memory, the information is coupled, as desired, to the processor. The cache controller then restores the information formerly in the first location, by coupling the contents of the buffer back into the first location within the cache memory.