一种灵活TAM总线分配的SoC测试调度方法

Flexible TAM-bus assignment method for solving SoC test scheduling problem

测试调度问题已成为SoC发展的瓶颈,这一NP完全问题经常被抽象成二维装箱问题。传统方法的出发点是将一个IP核分配一组固定的连续的测试总线,并求得此时的测试时间,将其分别映射成一个待装箱的小矩形的宽和长。对这一问题进行扩展,提出一种灵活TAM总线分配的方法,解决SoC测试调度问题。该方法的主要思想是将一个IP核灵活的分配多组测试总线,把代表该IP核信息的一个矩形从宽度上分割为多个矩形。同时,利用B*-Tree结构描述"箱体布局",采用一种新的组合优化算法——交叉熵方法,对其进行求解。最后将其应用在ITC’02标准测试集上,实验表明,基于灵活TAM总线分配方法的SoC测试调度比现有的测试调度方法能更有效地降低SoC的测试时间。

Test scheduling is an important issue in system-on-a-chip（SoC）,and is widely recognized as a major bottleneck in SoC design.This NP-complete problem is equivalent to a 2-D bin-packing problem.In traditional method,each IP core is represented by a rectangle whose height equals to the test access mechanism（TAM） width and width equals to the test time.In this paper,we present a flexible TAM assignment method for solving SoC test scheduling problem.The main idea of the method is that the IP core is assigned to a group of test buses and the rectangle representing the IP core is divided into several ones in width.Meanwhile,cross-entropy（CE） method based on probability density function,and B＊-Tree structure based floor planning technique are used to solve the SoC test scheduling problem.The method was applied on ITC＇02 benchmark test set,and experimental results show that compared with existing scheduling methods the proposed method can effectively reduce test time.