Patent · US Expired

Resolving processor and system bus address collision in a high-level cache

US5832276A · kind A · utility

27Cited by
11References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 7, 1996
Grant dateNov 3, 1998
Priority date
Expiry dateOct 7, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F12/0811
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A L2 cache for resolving collisions between processor request originating from a processor and system request originating from a computing unit attached to the system bus is provided. First, the L2 cache snoops a system request to access a shared resource. This shared resource is often an area of main memory contained in the L2 cache. Next, the L2 cache receives a processor request to access the shared resource also. The L2 cache will delay sending an acknowledge signal to the processor. The L2 cache then makes a determination as to whether the address and system request type must be sent to the processor. If data associated with the system request would alter a line in a L1 cache associated with the processor, a retry signal is sent to the processor. If the system request would not alter a line in the L1 cache, the L2 cache will wait until the system request finishes accessing the shared resource to process the processor request, thereby avoiding the sending of a retry signal to the processor.

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