Patent · US Expired

Method and system for bypass prefetch data path

US6449698B1 · kind B1 · utility

27Cited by
5References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 26, 1999
Grant dateSep 10, 2002
Priority date
Expiry dateAug 26, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F2212/6022
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method and system for bypassing a prefetch data path is provided. Each transaction within a system is tagged, and as transactions are issued for retrieving data, the system has a data prefetch unit for prefetching data from a processor, a memory subsystem, or an I/O agent into a prefetch data buffer. A prefetch data buffer entry is allocated for a data prefetch transaction, and the data prefetch transaction is issued. While the prefetch transaction is pending, a read transaction is received from a transaction requestor. The address for the read transaction is compared with the addresses of the pending data prefetch transactions, and in response to an address match, the prefetch data buffer entry for the matching prefetch transaction is checked to determine whether data has been received for the data prefetch transaction. In response to a determination that data has not been received for the data prefetch transaction, the prefetch data buffer entry is deallocated, and the transaction tag for the data prefetch transaction is stored in a table for bypassing a prefetch data path. When data for a data prefetch transaction is received, its transaction tag is compared with transaction t…

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