A general time model for the specification and design of embedded real-time systems

Design of complex embedded systems feasible with current and upcoming semiconductor technologies necessitates consideration of real-time from the beginning. However, the commonly used specification techniques do not consider temporal aspects in general like fulfillment of high level timing requirements or dynamic reactions on timing violations. In this paper, we discuss the restrictions of current specification techniques for embedded real-time systems and present a general time model that solves this issue. The time model contains the progress of time, the measurement of time and the specification of timing requirements based on event traces. In contrast to earlier techniques, preconditions determine the actual relevance of a specific timing bound. Exemplified for SDL, a solution for the specification of temporal aspects is shown. The advantages of this solution are discussed in a hardware/software co-design case study from the mobile communication area.     

Fast and accurate FPGA-based framework for processor architecture vulnerability analysis

This paper presents a fast, accurate, and flexible FPGA-based fault emulation platform, namely FARAVAM that can be exploited for AVF analysis in modern microprocessors. The proposed approach provides fault injection capabilities supporting automatic modification of post-synthesis net-lists and introduces a highly controllable and observable transient fault analysis environment. The presented vulnerability analysis platform using both exhaustive and random fault emulation approaches, provides useful information for identifying areas threatening reliability to make processors more fault tolerant. We applied our platform for extracting the best trade-offs between precision and speed up in vulnerability analysis of MIPS processor. The experimental results indicate that in addition to having high precision we obtain about seven orders of magnitude speed up in comparison with simulation based vulnerability analysis techniques.     

Combining data remapping and voltage/frequency scaling of second level memory for energy reduction in embedded systems

In this paper we show that the energy reductions obtained from using two techniques, data remapping (DR) and voltage/frequency scaling of off-chip bus and memory, combine to provide interesting trade offs between energy, execution time and power. Both methods aim to reduce the energy consumed by the memory subsystem. DR is a fully automatic compile time technique applicable to pointer-intensive dynamic applications. Voltage/frequency scaling of off-chip memory is a technique applied at the hardware level. When combined together, energy reductions can be as high as 49.45%. The improvements are verified in the context of three OLDEN pointer-centric benchmarks, namely Perimeter, Health and TSP.     

A HW/SW Co-Verification Technique for FPGA Test

Field programmable gate arrays （FPGAs） have wide and extensive applications in many areas. Due to programmable feature of FPGAs, faults of FPGAs can be easily tolerated if fault sites can be located. A hardware/software （HW/SW） co-verification technique for FPGA test is proposed in this paper. Taking advantage of flexibility and observability of software in conjunction with high-speed simulation of hardware, this technique is capable of testing each input/output block （IOB） and configurable logic block （CLB） of FPGA automatically, exhaustively and repeatedly. Fault cells of FPGA can be positioned automatically by the proposed approach. As a result, test efficiency and reliability can be enhanced without manual work.     

Improving Software Performance with Configurable Logic

We examine the energy and performance benefits that can be obtained by re-mapping frequently executed loops from a microprocessor to reconfigurable logic. We present a design flow that finds critical software loops automatically and manually re-implements these inconfigurable logic by implementing them in SA-C, a C language variation supportinga dataflow computation model and designed to specify and map DSP applicationsonto reconfigurable logic. We apply this design flow on several examples fromthe MediaBench benchmark suite and report the energy and performance improvements.