Architecture Exploration for Embedded Processors with LISA

Today more than 90% of all programmable processors are employed in embedded systems. This number is actually not surprising, contemplating that in a typical home you might find one or two PCs equipped with high-performance standard processors, and probably dozens of embedded systems, including electronic entertainment, household, and telecom devices, each of them equipped with one or more embedded processors. The question arises why programmable processors are so popular in embedded system design. The answer lies in the fact that they help to narrow the gap between chip capacity and designer productivity. Embedded processors cores are nothing but one step further towards improved design reuse, just along the lines of standard cells in logic synthesis and macrocells in RTL synthesis in earlier times of IC design. Additionally, programmable processors permit to migrate functionality from hardware to software, resulting in an even improved reuse factor as well as greatly increased flexibility. The LISA processor design platform (LPDP) presented in Architecture Exploration for Embedded Processors with LISA addresses recent design challenges and results in highly satisfactory solutions. The LPDP covers all major high-level phases of embedded processor design and is capable of automatically generating almost all required software development tools from processor models in the LISA language. It supports a profiling-based, stepwise refinement of processor models down to cycle-accurate and even RTL synthesis models. Moreover, it elegantly avoids model inconsistencies otherwise omnipresent in traditional design flows. The next step in design reuse is already in sight: SoC platforms, i.e., partially pre-designed multi-processor templates that can be quickly tuned towards given applications thereby guaranteeing a high degree of hardware/software reuse in system-level design. Consequently, the LPDP approach goes even beyond processor architecture design. The LPDP solution explicitly addresses SoC integration issues by offering comfortable APIs for external simulation environments as well as clever solutions for the problem of both efficient and user-friendly heterogeneous multiprocessor debugging.