Post-Silicon Debugging

After traveling through India and Russia with David Katch earlier this year, I ended up with the misperception that the only things happening at University of Michigan involved football and basketball. But as it turns out, there's more than sports going in Ann Arbor, particularly when it comes to engineering.

For instance, what engineering researchers at the university have come up with is a technique to automate post-silicon debugging. That is, they've developed a way to fix design bugs and wrong wire connections in computer chips after they've been fabricated in silicon.

The methodolgy, called FogClear, is a debugging technique that repairs some electrical errors while preserving functional correctness. FogClear uses puzzle-solving search algorithms to diagnose problems early on and automatically adjust the blueprint for the chip.

According to Kai-Hui Chang, who along with professors Igor Markov and Valeria Bertacco developed the methodolgy, "bugs found post-silicon are often very difficult to diagnose and repair because it is difficult to monitor and control the signals that are buried inside a silicon die, or chip. Up until now engineers have handled post-silicon debugging more as an art than a science."

FogClear automates this process by searching for and finding the simplest way to fix a bug that has the least impact on the working parts of the chip. The solution usually requires reconnecting certain wires, and does not affect transistors.

And after a rocky start says David, the football team isn't doing too badly either.

Posted by Jon Erickson at 12:09 PM  Permalink