Debug support for complex systems on-chip: a review

The introduction of complex systems-on-chip (SoC) devices with multiple processor cores presents new challenges for embedded systems developers. Novel development tools specifically targeting complex SoC will help overcome these challenges, but are typically limited by inadequate debug support facilities within the SoC. High-quality debug support with advanced features is essential to take full advantage of complex SoC devices in challenging applications while simultaneously reducing development time. Here, existing strategies for providing comprehensive SoC debug support targeting hard real-time applications, such as automotive control, where development challenges are overwhelming are reviewed. This overview includes an evaluation of the available solutions and their suitability for use with the next generation of complex SoC based on multiple processor cores. It is shown that many existing solutions do not readily permit developers to take advantage of the complex features integrated into the next generation of SoC. The essential features of debug support for multiple processor core SoCs are summarised and discussed. Recommendations are made for SoC designers and for the future direction of research in this area, with the aim of providing a more suitable foundation for new development tools. Such tools are badly needed for all hard real-time embedded systems and are paramount to managing the development complexity introduced by SoC devices with multiple highly interactive processor cores and active peripherals.