In this tutorial paper, we will outline a solution for prototyping, programming and implementing Application Specific Instruction-set Processors (ASIPs). A general introduction into this class of processor architectures and their characteristics is provided. The Synopsys Processor Designer tool suite and the LISA language for ASIP design are jointly introduced in the context of a H.264 design example. Finally, implementation results are presented.

Almost all SoC designs today use hardware prototyping at some point of the development cycle to perform hardware/software validation or test interfaces to real-world stimulus. Recently, virtual prototypes have emerged as a way to run system level tests and perform hardware/software co-simulation before silicon or hardware prototypes are available. Does the emergence of virtual prototyping mean the end for FPGA-based prototypes? Will the hardware prototype continue to live on as an integral part of the SoC design cycle? Will hybrids of virtual and hardware prototypes be the answer? Join our expert panelists in a spirited discussion on the best approach for speeding the verification and validation of complex SoC using system prototypes. Virtual, hardware or hybrid -- which will reign supreme?

Multi Processor SoC (MPSoC) are being designed today. MPSoC design can help achieve aggressive performance and low power targets but it creates new design challenges: How to design the interconnect fabric and memory sub-system to allow the massive data movement required in a multi processor SoC environment? How to develop, debug and verify HW and SW functionality in a MPSoC design? Is MPSoC design an inflection point that will require new design methods including ESL methodologies?

Increased product design cost and risk have been driving the electronics industry to an increased focus on developing "product platforms." When a product platform requires eighteen months to three years to develop at a cost of as much as $500 million, and the cost is expected to be amortized over as many as 100 derivative products over a period of three to five years, the definition of the hardware and software architecture becomes extremely critical. The architecture often needs to be able to support emerging product requirements over the life of the platform without having to re-spin the chip. This need creates conflicting requirements for the platform. On one hand the solution needs to be customized to achieve the targeted performance and cost close to an ASIC. On the other hand there is a need for flexibility close to a programmable solution, where modifications and enhancements can be done by software changes rather then by re-spinning the hardware.

Architecture description languages (ADL) have been established to aid the design of application-specific instruction-set processors (ASIP). Their main contribution is the automatic generation of a software toolkit, including C compiler, assembler, linker, and instruction-set simulator. Hence, the challenge in the design of such ADLs is to unambiguously capture the architectural information required for the toolkit generation in a single model. This is particularly difficult for C compiler and simulator, as both require information about the instructions' semantics, however, while the C compiler needs to know what an instructions does, the simulator needs to know how. Existing ADLs solve this problem by either introducing redundancy or by limiting the language's flexibility.This paper presents a novel, mixed-level approach for ADL-based instruction-set description, which offers maximum flexibility while preventing from inconsistencies. Moreover, it enables capturing instruction- and cycle-accurate descriptions in a single model. The feasibility and design efficiency of our approach is demonstrated with a number of contemporary, real-world processor architectures.

Architecture description languages are widely used to perform architecture exploration for application-driven designs, whereas the RT-level is the commonly accepted level for hardware implementation. For this reason, design parameters such as timing, area or power consumption cannot be taken into consideration accurately during design space exploration. Design automation tools currently used to bridge this gap are either limited in the flexibility provided or only generate fragments of the architecture. This paper presents a synthesis tool which preserves the full flexibility of the architecture description language LISA, while being able to generate the complete architecture on RT-level using systemC. This paper also presents two real world architecture case studies to prove the feasibility of our approach.

Current and future SoC designs will contain an increasing number of heterogeneous programmable units combined with a complex communication architecture to meet flexibility, performance and cost constraints. Designing such a heterogenous MP-SoC architecture bears enormous potential for optimization, but requires a system-level design environment and methodology to evaluate architectural alternatives. This paper proposes a methodology to jointly design and optimize the processor architecture together with the on-chip communication based on the LISA Processor Design Platform in combination with systemC transaction level models. The proposed methodology advocates a successive refinement flow of the system-level models of both the processor cores and the communication architecture. This allows design decisions based on the best modeling efficiency, accuracy and simulation performance possible on the respective abstraction level. The effectiveness of our approach is demonstrated by the exemplary design of a dual-processor JPEG decoding system.

Today, designers of next-generation embedded processors and software are increasingly faced with short product lifetimes. The resulting time-to-market constraints are contradicting the continually growing processor complexity. Nevertheless, an extensive design-space exploration and product verification is indispensable for a successful market launch. In the last decade, instruction-set simulators have become an essential development tool for the design of new programmable architectures. Consequently, the simulator performance is a key factor for the overall design efficiency. Motivated by the extremely poor performance of commonly used interpretive simulators, research work on fast compiled instruction-set simulation was started ten years ago. However, due to the restrictiveness of the compiled technique, it has not been able to push through in commercial products. In this paper, we tie up with our previous research on retargetable, compiled simulation techniques, and provide a discussion about their benefits and limitations using a particular compiled scheme, static scheduling, as an example. As a conclusion, we eventually present a novel retargetable simulation technique, which combines the performance of traditional compiled simulators with the flexibility of interpretive simulation. This technique is not limited to any class of architectures or applications and can be utilized from architecture exploration up to end-user software development. We demonstrate workflow and applicability of the so-called just-in-time cache-compiled simulation technique by means of state-of-the-art real-world architectures.

Current and future SoC designs will contain an increasing number of programmable units. To be able to tailor and debug these processors in their system context at the highest possible overall simulation speed, we propose a methodology and the necessary tooling for a multiprocessor debugging environment which allows a flexible runtime tradeoff between observability and simulation speed. This approach has been applied on a complex SoC case study.

This paper presents a novel instruction encoding generation technique for use in architecture exploration for application specific processors. The underlying exploration methodology is based on successive processor model refinement combined with simulation and profiling. Previous approaches require the tedious manual specification of binary instruction opcodes even at very early design stages due to the need to generate profiling tools. The proposed automatic technique eliminates this bottleneck in ASIP design. It is well adapted to the hierarchical processor modeling style of contemporary architecture description languages. Experimental evaluation for several real-life processor architectures confirms the practical applicability of the presented encoding techniques. Moreover, the results indicate that very compact instruction encoding schemes are generated that compete very well with hand-optimized encodings.

In the last decade, instruction-set simulators have become an essential development tool for the design of new programmable architectures. Consequently, the simulator performance is a key factor for the overall design efficiency. Based on the extremely poor performance of commonly used interpretive simulators, research work on fast compiled instruction-set simulation was started ten years ago. However, due to the restrictiveness of the compiled technique, it has not been able to push through in commercial products. This paper presents a new retargetable simulation technique which combines the performance of traditional compiled simulators with the flexibility of interpretive simulation. This technique is not limited to any class of architectures or applications and can be utilized from architecture exploration up to end-user software development. The work-flow and the applicability of the so-called just-in-time cache compiled simulation (JIT-CCS) technique will be demonstrated by means of state of the art real world architectures.

This paper presents a methodology to automatically generate production quality software development tools for programmable architectures using the machine description language LISA. Various architectures presenting diverse architectural originalities will be presented and the feasibility of automatically generating simulator, assembler, linker and graphical debugger frontend are discussed. The presented approach is not limited to a fixed abstraction level-case studies of the Texas Instruments C62x and C54x, the Analog Devices ADSP2101 as well as the ARM7 show the applicability of the methodology from cycle/phase to instruction accurate models.

This paper presents a survey on modeling issues of programmable architectures using the machine description language LISA. Various architectures presenting diverse architectural characteristics are presented and the feasibility of automatically generating simulator, assembler, linker and graphical debugger frontend discussed. The presented approach is not limited to a fixed abstraction level-case studies of the Texas Instruments C62/spl times/ and C54/spl times/, the Analog Devices ADSP2101 as well as the ARM7 show the applicability of the methodology from cycle/phase to instruction accurate models.

The development of application specific instruction set processors (ASIP) is currently the exclusive domain of the semiconductor houses and core vendors. This is due to the fact that building such an architecture is a difficult task that requires expert knowledge in different domains: application software development tools, processor hardware implementation, and system integration and verification. This paper presents a retargetable framework for ASIP design which is based on machine descriptions in the LISA language. From that, software development tools can be automatically generated including HLL C-compiler, assembler, linker, simulator and debugger frontend. Moreover, synthesizable HDL code can be derived which can then be processed by standard synthesis tools. Implementation results for a low-power ASIP for DVB-T acquisition and tracking algorithms designed with the presented methodology are given.

The development of application-specific instruction-set processors (ASIP) is currently the exclusive domain of the semiconductor houses and core vendors. This is due to the fact that building such an architecture is a difficult task that requires expertise in different domains: application software development tools, processor hardware implementation, and system integration and verification. This paper presents a retargetable framework for ASIP design which is based on machine descriptions in the LISA language. From that, software development tools can be generated automatically including high-level language C compiler, assembler, linker, simulator, and debugger frontend. Moreover, for architecture implementation, synthesizable hardware description language code can be derived, which can then be processed by standard synthesis tools. Implementation results for a low-power ASIP for digital video broadcasting terrestrial acquisition and tracking algorithms designed with the presented methodology are given. To show the quality of the generated software development tools, they are compared in speed and functionality with commercially available tools of state-of-the-art digital signal processor and /spl mu/C architectures.