Patent · US Expired

Apparatus and method for implementing a ROM patch using a lockable cache

US7290081B2 · kind B2 · utility

25Cited by
16References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 14, 2002
Grant dateOct 30, 2007
Priority date
Expiry dateMay 14, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F12/126
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A ROM patching apparatus for use in a data processing system that executes instruction code stored in the ROM. The ROM patching apparatus comprises: 1) a patch buffer for storing a first replacement cache line containing a first new instruction suitable for replacing at least a portion of the code in the ROM; 2) a lockable cache; 3) core processor logic operable to read from an associated memory a patch table containing a first table entry, the first table entry containing 1) the first new instruction and 2) a first patch address identifying a first patched ROM address of the at least a portion of the code in the ROM. The core processor logic loads the first new instruction from the patch table into the patch buffer, stores the first replacement cache line from the patch buffer into the lockable cache, and locks the first replacement cache line into the lockable cache.

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