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:
Apr. 15, 2003
Filed:
Nov. 04, 1999
George Henry Ahrens, Pflugerville, TX (US);
George John Dawkins, Austin, TX (US);
Michael Youhour Lim, Leander, TX (US);
Timothy Lee Toohey, Austin, TX (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method and apparatus for detecting an error condition during initialization of a multiprocessor data processing system is provided. A master processor identification indicator is initialized to an initial value by a service processor in the data processing system. The master processor identification indicator may be a location in nonvolatile RAM to protect data integrity. One of the plurality of processors in the multiprocessor system is selected to be the master processor by being released by the service processor and winning the “race condition” to fetch the first instruction from memory for program execution. This processor then sets the master processor identification indicator to a unique processor identification value. The initial value may be a spoof number indicating whether the master processor has yet written its unique processor identification value. At some later point in time, the service processor detects a freeze or hang condition in the data processing system. The service processor reads the value of the master processor identification indicator and reports the value of the master processor identification indicator to indicate which processor among the plurality of processors in the data processing system was selected as the master processor prior to the detection of the hang condition.