Paper accepted at LADC (II)
The paper entitled “ Speeding-up robustness assessment of HDL models through profiling and multi-level fault injection”, authored by Ilya Tuzov, David de Andrés and Juan-Carlos Ruiz, has been accepted at LADC 2018.
Abstract:
Simulation-based fault injection is an indispensable technique to assess the robustness of hardware components defined by means of hardware description languages (HDL). However, the high complexity of modern hardware and its strict verification accuracy requirements lead to an unfeasible number of fault injection experiments, even when following statistical (instead of exhaustive) approaches, as accurate implementation-level models are up to three orders of magnitude slower than (inaccurate) behavioural ones. This paper proposes the combined use of multi-level fault injection in sequential logic and the profiling of the use of combinational logic to guarantee results’ accuracy while keeping experimentation duration within reasonable time-bounds. First, the sequential logic generated at the implementation-level model is matched with associated structures at its related behavioural-level model. In such a way, most fault injection experiments targeting sequential logic could be executed at the much faster behavioural level, while maintaining the accuracy of results. Second, by profiling the implementation-level model, run-time statistics (inactive macrocells, switching activity, etc.) can be exploited to keep result precision while reducing the number of experiments targeting combinational logic. The case study of three embedded processor models illustrates both approaches and quantifies the experimental speed-up derived from their combined use.
Paper accepted at LADC (I)
The paper entitled “Correction of Adjacent Errors with Low Redundant Matrix Error Correction Codes”, authored by J. Gracia-Moran, L.J. Saiz-Adalid, J.C. Baraza-Calvo and P.J. Gil-Vicente, has been accepted at LADC 2018.
Abstract:
The continuous growth of the integration scale in CMOS circuits has derived in an increase in the memory systems capacity, but also in their fault rate. In this way, the probabilities of suffering Single Cell Upsets (SCUs) or Multiple Cell Upsets (MCUs) has thus raised.
Traditionally, Error Correction Codes (ECCs) are used in memory systems to correct errors. However, when using ECCs, it is necessary to find a good balance between the redundancy of the code; the area, power consumption and delay overheads of the encoding and decoding circuits; and the error coverage achieved.
In this work, we present two new low-redundant matrix ECCs that are able to correct different types of adjacent errors. Both codes have the same error coverage, but different levels of redundancy. In this way, we have been able to study the influence of these different levels of low redundancy in the area, power consumption and delay overheads. We have also compared our proposals to a well-known matrix code, in terms of overhead vs. coverage using a recently introduced metric. In all cases, our proposals get better scores.