Patent · US Expired

Master-slave cache system for instruction and data cache memories

US5551001A · kind A · utility

93Cited by
16References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 29, 1994
Grant dateAug 27, 1996
Priority date
Expiry dateJun 29, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F12/0831
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A master-slave cache system has a large, set-associative master cache, and two smaller direct-mapped slave caches, a slave instruction cache for supplying instructions to an instruction pipeline of a processor, and a slave data cache for supplying data operands to an execution pipeline of the processor. The master cache and the slave caches are tightly coupled to each other. This tight coupling allows the master cache to perform most cache management operations for the slave caches, freeing the slave caches to supply a high bandwidth of instructions and operands to the processor's pipelines. The master cache contains tags that include valid bits for each slave, allowing the master cache to determine if a line is present and valid in either of the slave caches without interrupting the slave caches. The master cache performs all search operations required by external snooping, cache invalidation, cache data zeroing instructions, and store-to-instruction-stream detection. The master cache interrupts the slave caches only when the search reveals that a line is valid in a slave cache, the master cache causing the slave cache to invalidate the line. A store queue is shared between the ma…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.