Method and system for selecting from multiple boot code images to be loaded in a data processing system

• US 6,446,203 B1
• Filed: 05/24/1999
• Issued: 09/03/2002
• Est. Priority Date: 05/24/1999
• Status: Expired due to Term

• Current Assignee: Lenovo PC International Limited (Lenovo Group Ltd.)
• Original Assignee: International Business Machines Corporation
• Inventors: Blam, Norbert, Lo, Yuan-Chang, Stafford, James Michael, Aguilar, Maximino, Gorrell, John William Jr.
• Primary Examiner(s): Gaffin, Jeffrey
• Assistant Examiner(s): Mai, Rijue
• Application Number:
  US09/317,552
• Time in Patent Office: 1,198 Days
• Field of Search: 713/1, 713/2, 713/3, 713/100, 709/222, 709/220, 709/221, 710/1, 710/10, 710/14, 710/104, 714/36, 714/3, 714/170
• US Class Current: 713/2
• CPC Class Codes: G06F 9/4408 Boot device selection

Abstract

A computer system including a processor, a system memory, and a boot code storage device. The system memory is connected to the processor and is suitable for storing processor data and instructions. The boot code storage device includes an image selection indicator for indicating which of multiple boot code images are to be loaded. The computer system further includes means for initiating a boot sequence stored on the boot code storage device. The boot sequence selects from first and second boot images based upon the state of the image selection indicator and loads the selected image into the system memory in response to a boot event. In one embodiment, the image selection indicator is in an initial state until the boot code sequence successfully loads a boot image. The image selection indicator is set to a value indicative of the loaded image when one of the boot images is successfully loaded. The boot code storage sequence attempts, in the preferred embodiment, to load the previously load boot image when the system detects a setting of the image selection indicator indicative of a previously loaded boot image. In the preferred embodiment, the boot code sequence responds to a specified user input sequence by presenting the user with a configuration screen suitable for altering the value of the image selection indicator such that the user may later the boot image that will be loaded during a subsequent execution of the boot sequence. In one embodiment, the first boot image is a BIOS based boot image and the second image is a network based (non-BIOS) boot image. The boot code storage device is preferably a flash memory device.

Claims

1. A computer system comprising:

a processor;

a system memory connected to the processor and suitable for storing processor data and instructions;

a boot code storage device including an image selection indicator; and

means for initiating a boot sequence stored on the boot code storage device, wherein the boot sequence selects from first and second boot images based upon the state of the image selection indicator and loads the selected image into the system memory in response to a boot event, wherein the first boot image comprises a BIOS boot image suitable for use with BIOS-based operating systems and wherein the second boot image comprises a network boot image suitable for use with a network operating system.

2. The computer system of claim 1, wherein the first and second boot code images are stored on the boot code storage device.

3. The computer system of claim 1, wherein the image selection indicator is in an initial state until the boot code sequence successfully loads a boot image.

4. The computer system of claim 1, wherein, in response to successfully loading one of the boot images, the image selection indicator is set a value indicative of the loaded image.

5. The computer system of claim 1, wherein, in response to detecting a setting of the image selection indicator indicative of a previously loaded boot image, the boot code storage sequence attempts to load the previously load boot image.

6. The computer system of claim 1, wherein the boot code sequence responds to a specified user input sequence by presenting the user with a configuration screen suitable for altering the value of the image selection indicator.

7. The computer system of claim 1, wherein the second boot image includes an Executable and Linking Format (ELF) compliant header section.

8. The computer system of claim 7, wherein the second boot image comprises a JavaOS boot image.

9. A boot code storage device for use with a computer system, wherein the boot code storage device is configured with first and second boot code images and an image selection indicator, and further configured with a boot code storage sequence that selects the first or second boot code images, responsive to the value of the image selection indicator, and loads the selected image into a system memory of a computer system, wherein the first boot code image comprises a BIOS-based boot image suitable for use with a BIOS-based operating system and the second boot code image comprises a network boot image suitable for use with a network operating system.

10. The storage device of claim 9, wherein the boot code storage device comprises a flash memory device.

11. The storage device of claim 9, wherein the image selection indicator is in an initial state until the boot code sequence successfully loads either the first or second boot image.

12. The storage device of claim 9, wherein, in response to successfully loading one of the boot images, the boot code sequence sets the image selection indicator to a value indicative of the loaded image.

13. The storage device of claim 9, wherein, in response to detecting a setting of the image selection indicator indicative of a previously loaded boot image, the boot code storage sequence attempts to load the previously load boot image.

14. The storage device of claim 9, wherein the boot code sequence responds to a specified user input sequence by presenting the user with a configuration screen suitable for altering the value of the image selection indicator.

15. The storage device of claim 9, wherein the second boot image includes an Executable and Linking Format (ELF) compliant header section.

16. The storage device of claim 15, wherein the second boot image comprises a JavaOS boot image.

17. A method of booting a computer system, comprising:

initiating a boot code sequence responsive to a boot event and determining the state of an image selection indicator;

responsive to detecting an initial state of the image selection indicator, attempting in sequential order, to load one of a set of boot images until one of the boot images loads successfully and setting the image selection indicator to a value indicative of the successfully loaded boot image, wherein at least one of the set of boot images is a BIOS-based boot image and at least one of the set of boot images is a network-based boot image; and

responsive to detecting a state of the image selection indicator indicative of a previously loaded boot image, loading the previously loaded boot image into system memory.

18. The method of claim 17, further comprising, responsive to a user input sequence during execution of the boot code sequence, displaying a configuration screen suitable for altering the state of the image selection indicator.

19. The method of claim 17, wherein altering the state of the image selection indicator comprises programming a flash memory device on which the image selection indicator is located.

20. The method of claim 17, wherein boot event the comprises a network wake-up event.

21. The method of claim 17, wherein the set of boot images includes a BIOS based boot image and a network based boot image.