May 27, 2010 -- Code coverage is an essential metric for completion of the verification of a SOC or an IP. The code coverage report helps you identify verification loopholes by analyzing the uncovered coverage metrics in the report. The target coverage numbers are defined for all the code coverage metrics (Line, Toggle, Condition and FSM). Additional verification cycles are required if the code coverage target metrics are not met. It is required to meet 100% coverage goals but it does not mean that verification is complete. However, it is an important metric for the measure of the verification. Code coverage metrics must be used in conjunction with other metrics such as functional coverage, assertion coverage, and formal equivalence checkers to measure verification completion.

In general, verification is a two-dimensional problem. The testbench development, coverage convergence (functional and code) are the two dimensions of the verification. The configurable IP provides third dimension to the IP verification namely Multiple Configurations. Verifying the configurable IP across multiple configurations is a challenging task and challenge lies in both the dimensions. Achieving code coverage goals for multiple configurations requires special attention as it might impact the verification schedule if not addressed properly.

By P. Venkata Giri Kumar, Nivin Ninan George, K. Sarannya, Sriram Balasubramanian, and Srikanth Vadanaparthi. (All are with Synopsys, Inc.)