On NoC Bandwidth Sharing for the Optimization of Area Cost and Test Application Time

Fawnizu Azmadi HUSSIN  Tomokazu YONEDA  Hideo FUJIWARA  

IEICE TRANSACTIONS on Information and Systems   Vol.E91-D   No.7   pp.1999-2007
Publication Date: 2008/07/01
Online ISSN: 1745-1361
DOI: 10.1093/ietisy/e91-d.7.1999
Print ISSN: 0916-8532
Type of Manuscript: PAPER
Category: Dependable Computing
SoC test scheduling,  test wrapper,  test access mechanism,  NoC-reuse,  bandwidth sharing,  

Full Text: PDF>>
Buy this Article

Current NoC test scheduling methodologies in the literature are based on a dedicated path approach; a physical path through the NoC routers and interconnects are allocated for the transportation of test data from an external tester to a single core during the whole duration of the core test. This approach unnecessarily limits test concurrency of the embedded cores because a physical channel bandwidth is typically larger than the scan rate of any core-under-test. We are proposing a bandwidth sharing approach that divides the physical channel bandwidth into multiple smaller virtual channel bandwidths. The test scheduling is performed under the objective of co-optimizing the wrapper area cost and the resulting test application time using two complementary NoC wrappers. Experimental results showed that the area overhead can be optimized (to an extent) without compromising the test application time. Compared to other NoC scheduling approaches based on dedicated paths, our bandwidth sharing approach can reduce the test application time by up to 75.4%.