Method and system for performing function-specific memory checks within a vehicle-based control system

• US 7,533,322 B2
• Filed: 11/03/2005
• Issued: 05/12/2009
• Est. Priority Date: 11/03/2005
• Status: Expired due to Fees

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (General Motors Company)
• Inventors: Katrak, Kerfegar K., Bauerle, Paul A.
• Primary Examiner(s): Abraham; Esaw T
• Assistant Examiner(s): Ahmed; Enam
• Application Number:
  US11/266,609
• Publication Number:
  US 20070101236A1
• Time in Patent Office: 1,286 Days
• Field of Search: 714/763
• US Class Current: 714/763
• CPC Class Codes: G06F 11/1004 to protect a block of data words, e.g. CRC or checksum G06F11/1076 takes precedence; security arrangements for protecting computers or computer systems against unauthorized activity G06F21/00

Abstract

Integrity of data stored in a memory space associated with a vehicle-based control system (such as a traction enhancement system) is verified through the use of sub-module checksums. A checksum for one or more subsystem modules is initially calculated based upon a checksum routine and the values of data residing in the portions of the memory space associated with the subsystem of interest. A global checksum is also initially calculated based upon data associated with the entire memory space. If the global checksum matches an expected value, the subsystem checksum(s) are stored as expected subsystem checksums. During subsequent operation, a second subsystem checksum is calculated and compared against the expected checksum value for the subsystem to verify the integrity of data residing within the memory space associated with the subsystem.

Claims

1. A method for rapidly verifying the data integrity of a subsystem operating within a memory space associated with a vehicle-based control system, the method comprising the steps of:

initially calculating a subsystem checksum and a global checksum, wherein the subsystem checksum is calculated using a checksum routine based upon data residing in a portion of the memory space associated with the subsystem, and wherein the global checksum is calculated based upon data associated with a substantial totality of the memory space;

If the global checksum matches an expected value, storing the subsystem checksum as an expected subsystem checksum and, if the global checksum does not match the expected value, not storing the subsystem checksum as the expected subsystem checksum; and

Subsequently verifying that a second subsystem checksum calculated using the checksum routine based upon the data residing in the portion of the memory space associated with the subsystem matches the expected subsystem checksum.

2. The method of claim 1 wherein the subsystem is one of a plurality of subsystems residing within the memory space.

3. The method of claim 2 wherein each of the plurality of subsystem checksums is computed according to a common checksum routine.

4. The method of claim 2 wherein at least a first one of the plurality of subsystem checksums is computed according to a first checksum routine, and wherein a second one of the plurality of subsystem checksums is computed according to a second checksum routine different from the first checksum routine.

5. The method of claim 2 wherein the calculating step comprises calculating a plurality of subsystem checksums, wherein each of the plurality of subsystem checksums is associated with one of the plurality of subsystems.

6. The method of claim 5 wherein the storing step comprises storing each of the plurality of subsystem checksums as a plurality of expected subsystem checksums if the global checksum matches the expected value.

7. The method of claim 6 wherein the verifying step comprises subsequently verifying that each of a plurality of second subsystem checksums match the expected subsystem checksums for at least two of the plurality of subsystems.

8. The method of claim 2 further comprising the step of identifying a fault occurring within the portion of the memory associated with at least one of the plurality of subsystems.

9. The method of claim 8 further comprising the step of adjusting a parameter associated with a second subsystem to compensate for the fault.

10. The method of claim 2 wherein the plurality of subsystems comprises a moding supervisor module, a motion control supervisor module, and a vehicle dynamics/yaw control supervisor.

11. The method of claim 10 wherein the plurality of subsystems further comprises a steering subsystem, a braking subsystem and a suspension subsystem.

12. The method of claim 1 further comprising the step of disabling the subsystem if the second subsystem checksum does not match the expected subsystem checksum.

13. The method of claim 1 further comprising the step of identifying a fault occurring within the portion of the memory associated with the subsystem if the second subsystem checksum does not match the expected subsystem checksum.

14. The method of claim 13 further comprising the step of adjusting the performance of the subsystem in response to the fault.

15. The method of claim 13 further comprising the step of repairing the fault.

16. A digital storage medium having computer-executable instructions stored thereon configured to execute the method of claim 1.

17. A control system for a vehicle, the system comprising:

a memory having a memory space associated with the control system;

subsystem means configured to execute within a portion of the memory space; and

a controller comprising;

means for calculating an initial subsystem checksum and a global checksum, wherein the initial subsystem checksum is calculated using a checksum routine based upon data residing in the portion of the memory space associated with the subsystem module, and wherein the global checksum is calculated based upon data associated with a substantial totality of the memory space;

means for storing the initial subsystem checksum, wherein the initial subsystem checksum is stored as an expected subsystem checksum if the global checksum matches an expected value and, if the global checksum does not match the expected value, the subsystem checksum is not stored as the expected subsystem checksum; and

means for subsequently verifying that a second subsystem checksum calculated using the checksum routine based upon the data residing in the portion of the memory space associated with the subsystem module matches the expected subsystem checksum.

18. The system of claim 17 wherein the subsystem means is one of a plurality of subsystem means each configured to execute within the memory space, and wherein the plurality of subsystem means comprises a steering subsystem, a braking subsystem and a suspension subsystem, and wherein the system is a traction enhancement system.

19. A traction enhancement system for a vehicle, the system comprising:

a digital memory having a plurality of portions associated with each of a plurality of subsystem processing modules, the plurality of subsystem processing modules comprising a steering subsystem module, a braking subsystem module and a suspension subsystem module; and

;

a controller in data communication with the digital memory configured to execute a traction enhancement program, wherein the traction enhancement program is configured at least in part to initially calculate a plurality of subsystem checksums and a global checksum, wherein each of the subsystem checksums is calculated based upon data residing in the portion of the memory space associated with one of the subsystem modules, and wherein the global checksum is calculated based upon data associated with a substantial totality of the memory space, and wherein the controller is further configured to store each of the subsystem checksums in the digital memory if the global checksum matches an expected value, to not store the subsystem checksums if the global checksum does not match the expected value, and to process a fault condition if the subsystem checksum for at least one subsystem module differs from a second subsystem checksum subsequently calculated based upon the data residing in the portion of the memory space associated with the at least one subsystem module.

20. The system of claim 19 wherein the controller is further configured to compute the subsystem checksum for a first one of the plurality of subsystems according to a first checksum routine, and to compute the subsystem checksum for a second one of the plurality of subsystems according to a second checksum routine that is different from the first checksum routine.