Fault resilient booting for multiprocessor computer systems

Patent 5790850 Issued on August 4, 1998. Estimated Expiration Date:

September 30, 2016. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

Distributed multi-processor boot system for booting each processor in sequence including watchdog timer for resetting each CPU if it fails to boot Patent #: 5450576
Issued on: 09/12/1995
Inventor: Kennedy

Inventor

Natu, Mahesh

Application

No. 723909 filed on 09/30/1996

US Classes:

713/2, Loading initialization program (e.g., booting, rebooting, warm booting, remote booting, BIOS, initial program load (IPL), bootstrapping)709/222Initializing

Examiners

Primary: Kriess, Kevin A.

Attorney, Agent or Firm

Kenyon & Kenyon

International Class

G06F 009/06

Abstract

A multiprocessor computer system determines that the hard reset designated BSP has failed by examining its status bits. The designated BSP then selects a processor from among the APs that will take the place of the designated BSP. The selection is accomplished by, successively for every AP indicated to be good by examining its corresponding status flag, determining whether the AP is present, starting up the AP if it is present, determining whether the AP has passed its BIST, and selecting the AP to take the place of the designated BSP if the AP has passed its BIST. The BSP then designates the selected AP as the BSP instead of itself. The bootstrap indicator bit of the selected AP is set to indicate that the AP is the BSP. The bootstrap indicator bit of the designated BSP is cleared. The computer system then undergoes a soft reset which causes the selected AP to become the BSP and begin running the BIOS code from the reset vector.