Predictable Matching of Demands on Networked Architectures (PreMaDoNa)
The PROGRESS Embedded Systems Roadmap 2001 notes that the highest priority of STW's Program for Research on Embedded Systems & Software (PROGRESS) is to promote, develop and facilitate the reuse of Intellectual Property (IP) blocks in an effort to reduce the design-complexity gap. Network-on-Chip (NoC) based platforms include various core blocks such as processors, memories and I/O blocks, which are interconnected by on-chip networks. It is believed that NoC-based platforms highly enable reuse of IP blocks and that they therefore form a suitable basis for future embedded systems.
The PreMaDoNa project focuses on the design and implementation of NoC-based platforms for multi-media applications. The research challenges mainly originate from the increasing complexity of multi-media applications and the ever-shortening design time to realise multi-media systems.
One of the major problems when mapping applications to multi-processor platforms like NoCs is dealing with real-time constraints. That is, how to satisfy timing-related requirements when using a platform that includes non-predictable elements like caches and shared buses? The problem of satisfying real-time constraints is worsened by the increasing dynamism of applications and the changing set of applications that actually run on a multi-processor platform. Especially in case of running multiple video applications, meeting real-time constraints becomes more and more difficult. Guaranteeing real-time behaviour therefore requires dynamic adaptation of the video quality (without being disruptive) and still satisfying non-functional requirements like latency and throughput constraints. This inspired PreMaDoNA's major research objective:
Together with the removal and/or software control of unpredictable elements in NoC-based platforms, PreMaDoNa pursues a predictable mapping methodology that supports reasoning about non-functional properties such as latency and throughput. More concrete, PreMaDoNA is centred around the following three tracks:
The definition, modelling and implementation of a NoC-based platform
The system architecture will be defined in terms of services that can be requested by an application. These services include both computation and communication services. The expected results are the system architecture itself, a resource manager, a computational model for mapping purposes, and a prototype realisation on an FPGA board.
A methodology for predictable design of NoC-based multi-media systems
In order to satisfy non-functional requirements, many design iterations may be required. This track aims at reducing the number of design iterations by taking non-functional requirements into account during the whole application modelling and mapping trajectory. Expected results are a mapping methodology supported by an analysis tool, which is embedded within a complete design flow.
Demonstrating predictable mapping of highly dynamic multi-media applications on a NoC-based platform
This requires applications to be parameterised for quality, which allows a Quality-of-Service (QoS) or resource manager to adjust the perceived quality according the availability of resources. Main result of this track is a demonstrator application (MPEG-4 video object-coding) running on the NoC-based platform developed in track 1.
A more elaborate description of the PreMaDoNa project can be found here.