Advances in semiconductor technology coupled with the increasing availability of soft and hard IP libraries enable embedded system designers to develop Systemson -Chip (SOCs) containing highly customized processors and memories for their specific applications. However, there is a strong demand for a methodology and tools that support efficient Design Space Exploration (DSE) of SOC architectures. Architecture Description Language (ADL)-based SOC codesign is a promising approach to efficient DSE of SOC architectures. ADLs are languages designed for specification of SOC architecture templates, and are used to perform early validation of SOC architectures, as well as to automatically generate software toolkits required to complete the integrated, and concurrent hardware and software design of the SOCs. In this paper we survey recent efforts in the use of ADLs. We conclude with a discussion of several major challenges facing ADL-based codesign of future SOCs. 1. Introduction Traditionally...

This paper presents a methodology to retarget the technique of compiled simulation for Digital Signal Processors (DSPs) using the modeling language LISA. In the past, the principle of compiled simulation as means for speeding up simulators has only been implemented for specific DSP architectures. The new approach presented here discusses methods of integrating compiled simulation techniques to retargetable simulation tools. The principle and the implementation are discussed in this paper and results for the TI TMS320C6201 DSP are presented.

. We describe a novel technique for code selection based on data-flow graphs, which arise naturally in the domain of digital signal processing. Code selection is the optimized mapping of abstract operations to partial machine instructions. The presented method performs an important task within the retargetable microcode generator CBC, which was designed to cope with the requirements arising in the context of custom digital signal processor (DSP) programming. The algorithm exploits a graph representation in which control-flow is modeled by scopes. 1 Introduction In the domain of medium-throughput digital signal processing, micro-programmable processor cores are frequently chosen for system realization. By adding dedicated hardware (accelerator paths), these cores are tailored to the needs of new applications. Optimized processor modules can be reused, which is a major benefit compared to high-level synthesis [28] where a completely new design is developed for each application. ...

Embedded systems present a tremendous opportunity to customize designs by exploiting the application behavior. Shrinking time-to-market, coupled with short product lifetimes create a critical need for rapid exploration and evaluation of candidate architectures. Architecture Description Languages (ADL) enable exploration of programmable architectures for a given set of application programs under various design con-straints such as area, power, and performance. The ADL is used to specify programmable embedded systems including processor, coprocessor and memory architectures. The ADL specification is used to generate a variety of software tools and models facilitating exploration and validation of candidate architectures. This chapter surveys the existing ADLs in terms of (a) the inherent features of the languages; and (b) the methodologies they support to enable simulation, compilation, synthesis, test generation, and validation of programmable embedded systems. It concludes with a discussion of relative merits and demerits of the existing ADLs, and expected features of future ADLs. 1

Fast processor simulators are needed for the software development ofembedded processors, for HW/SW cosimulation systems and for profiling and design of application specific processors. Such fast simulators can be generated based on the machine description language LISA. Using this language to model processor architectures enables the generation of compiled simulators on various abstraction levels, assemblers and compiler back-ends. The article discusses the requirements of software development tools on processor models and presents the approach based on the LISA language. Furthermore, the implementation of a retargetable environment consisting of compiled simulator, debugger and assembler is presented. Measurements for a verified, cycle-based LISA model of the TI TMS320C62x DSP show that this approach achieves between 37x and 170x higher simulation speed compared to a commercial simulator using a standard technique and the same accuracy level.

Modern Embedded Systems-on-Chips (SOCs) will allow the system designer to customize Intellectual Property (IP) cores (fixed and programmable), together with custom logic and large amounts of embedded memories. As the software content in these emerging embedded SOCs begins to dominate the SOC design process, there is a critical need for support of an integrated software development environment (including compilers, simulators and debuggers). Furthermore, since many characteristics of these processor core IPs (e.g., instruction-sets, memory configurations) are increasingly customizable, the entire software toolkit chain needs to be customized and generated to support both early design space exploration (for performance, power and cost constraints), as well as high-quality software generation. This paper first surveys recent efforts in Architecture Description Languages (ADLs) used to perform early validation and exploration of SOC architectures. The second part of the paper focuses on ap...