Shielding against design flaws with field repairable control logic

Correctness is a paramount attribute of any microprocessor design; however, without novel technologies to tame the increasing complexity of design verification, the amount of bugs that escape into silicon will only grow in the future. In this paper, we propose a novel hardware patching mechanism that can detect design errors which escaped the verification process, and can correct them directly in the field. We accomplish this goal through a simple fieldprogrammable state matcher, which can identify erroneous configurations in the processor's control state and switch the processor into formally-verified degraded performance mode, once a "match" occurs. When the instructions exposing the design flaw are committed, the processor is switched back to normal mode. We show that our approach can detect and correct infrequently-occurring errors with almost no performance impact and has approximately 2% area overhead. Categories and Subject Descriptors. B.8.1 [Performance and Rel...

• Type: Conference
• Year: 2006
• Where: DAC
• Authors: Ilya Wagner, Valeria Bertacco, Todd M. Austin
• Keywords: DAC 2006, Design Automation, Design Verification, Formally-verified Degraded Performance, Hardware Patching Mechanism