Here is a list of some completed research projects at ESLAB.
Embedded Systems Design
The main objective of this project is to develop algorithms for optimization of real-time applications implemented on power constrained network-on-chip architectures, using accurate delay and power models for the processor cores and communication infrastructure.
The worst-case execution time model, though it guarantees all deadlines, if feasible, leads to significant under-utilization of the hardware platform and implicitly to expensive products. Therefore, where applicable (soft real-time systems), a model based on stochastic task execution times is better suited for the design. The application is modeled as a set of task graphs. The tasks are periodic and statically mapped. The task deadlines are shorter than or equal to the task period. The probability distribution functions of the task execution times are arbitrary and given. The scheduling policies are given and arbitrary.
Our goal in this research project is the development of system level methodologies and design tools integrated in a design environment for embedded hardware/software systems. Starting form a high level and implementation independent specification, these methodologies, algorithms and tools support the designer during design space exploration, refinement and synthesis. We concentrate on aspects which are not sufficiently explored and are generated by recent developments in the area.
Modeling and Verification
A system level based design verification flow must solve three main problems:
- verification of the correct interaction between all IP-cores and of the system in the networked environment, driven by coverage metrics,
- production of a SW layer for the purpose of the embedded platform test, and
- verification of the correct modeling of system-level IP-cores and their correct mapping into RTL descriptions, driven by formal verification.
The solution of these problems require to correctly integrate verification and design into a robust flow, to smoothly move from verification languages (e.g., SystemC, System Verilog) to RTL languages, to combine dynamic and static verification techniques, thus exploiting and composing a variety of verification engines (e.g., SAT, High-Level Decision Diagrams, Hierarchical Petri Nets, EFSMs, etc.).
The project is a cooperation between several European academic and industrial partners. The focus of ESLAB lies on verification of the interaction between IP-cores, using a Petri-net based design representation.
One of the objectives of this project is the development of a modeling formalism that captures the most relevant aspects of embedded systems and, at the same time, has formal semantics. The second objective is devising formal verification techniques applicable to systems represented in our model.
This project aims at developing a methodology for formal verification in a context where the system model consist of predesigned components. These components have already been verified by their providers and are assumed to be correct. An important issue is to develop a method how to take advantage of this fact in order to reduce verification time. Another related issue is how to model the environment in which the components are placed.
Test, Design for Test, and Diagnosis
The focus of this research is on methods and tools to provide test solutions for system-on-chip (SoC) designs where hybrid BIST approach is used. This implies development of a global optimization strategy together with efficient scheduling approach as well as accurate test cost calculation methodology for SoC while assuming the hybrid BIST architecture. In this new context, we have to consider also test data transportation, test parallelization and clustering as well as test data compression issues.
The objective is to develop methodology, algorithms and tools for doing testability analysis and testability enhancement in the early phases of the design process. The methodologies and tools are used to guide design space exploration for designing minimal area, self-testable digital designs. Both built in self-test register (BIST) cost and wiring overhead cost are taken into consideration during synthesis for self-testability optimization process.
The focus of this research is on the development of methods and tools that are to be used when designing test solutions for system-on-chip (SoC) designs. We propose test architectures and corresponding efficient scheduling algorithms. The main objective is test time minimization while considering constraints such as power dissipation, test resource sharing, precedence constraints and interconnection test.
The main focus of this project is to develop methods for transportation and control of tests in System-On-Chip (SOC) designs. The main objective is to develop a test access methodology that reuses functional connections, e.g. busses or networks. The reason for this is to decrease the routing overhead. Additional buffers may be necessary in order to have concurrent application of the tests. Another property that is considered is the implementation of a test-controller used for directing the transmission of tests. In this project we propose a technique that deals with the test scheduling problem with this new properties while minimizing the test-controller and buffer size for a multi-core SOC.
Design of Self-healing System Chips
Project leader: Erik Larsson
Funding agency: The Swedish Foundation for International Cooperation in Research and Higher Education (STINT)
The SYDIC-Training project is devoted to the organization of training courses on system specification methodology, concepts and system validation methods for complex electronic systems. The project answers an increasing industry demand to efficient transfer of design methodology research results from academia to industry.