CSR: Small: Accelerating Microprocessor Post-Silicon Diagnosis with Statistical Inference

在现代复杂的微处理器中寻找漏洞是一项关键而艰巨的任务，必须熟练掌握，才能将设计从第一个硅芯片转移到发射。 逃脱的漏洞可能导致数字硅公司的灭亡。与此同时，寻找第一个硅原型的设计错误缺乏可观察性，可控性和可重复性所提供的前硅模拟框架。为了使该过程进一步复杂化，在真实的硅中显现的许多缺陷是复杂的异步交互和/或电异常的结果，这些异常通常不容易或不频繁地重复。 由于这些挑战，在早期硅中调试这些“转瞬即逝的错误”是一种黑魔法，如果调试过程不能顺利进行，可能会严重影响设计进度。本项目研究解决方案，以支持这些最具挑战性的后硅验证错误的有效诊断，这些错误只是偶尔出现。这些错误可能是功能、时序或电气错误，也可能是遗漏的制造缺陷。该方法需要在芯片上放置轻量级仪器，以在原型的测试执行期间收集数据。然后使用统计推断算法离线分析数据，以快速将验证工程师指向违规组件。该研究探索了一系列想法，以找到最有前途的分析仪器和算法。这项研究工作的结果使半导体公司能够缩短上市时间，同时提供高质量的产品，并降低逃逸错误的发生率;反过来，这项工作有利于社会，因为它为电子行业带来了进一步的规模和增长。

Finding bugs in modern complex microprocessors is a critical and daunting task that must be deftly mastered to move designs from first silicon to launch. Escaped bugs may lead to the demise of a digital silicon company. At the same time, looking for design errors on first silicon prototypes lacks the observability, controllability and repeatability afforded by pre-silicon simulation frameworks. To complicate the process further, many of the bugs that manifest in real silicon are the result of complex asynchronous interactions and/or electrical anomalies that are often not easily or frequently repeatable. Because of these challenges, debugging these "fleeting bugs" in early silicon is a black art that can significantly impact design schedules if the debugging process does not proceed smoothly.This project investigates solutions to support the efficient diagnosis of these most challenging post-silicon validation bugs, those that manifest only occasionally. These bugs may be functional, timing or electrical errors, or also missed manufacturing defects. The approach entails placing lightweight instrumentation on-chip to collect data during a prototype's test executions. The data is then analyzed offline using statistical inference algorithms to quickly point verification engineers to offending components. The research explores a range of ideas to find the most promising instrumentation and algorithms for analysis. The results of this research effort allow semiconductor companies to shorten their time to market while delivering high quality products, with low incidence of escaped bugs; in turn, the work benefits society in that it unlocks further scaling and growth for the electronics industry.