November 18, 2004

1. Qi Zhu, Abhijit Davare A Platform-based Design Flow for Kahn Process Networks Advisor: A. Sangiovanni-Vincentelli http://chess.eecs.berkeley.edu Step 3: Initial Sizing • Kahn Process Networks must be implemented with finite memory • Low channel sizes increase the coupling between the reader and writer processes and may also create deadlocks • Size the channels to decrease the likelihood of deadlock and reduce the interleaving penalty while meeting the storage constraints propagated from the previous step Abstract Design Flow Multimedia systems such as cellular phones and set-top boxes are well suited for the Platform-based design methodology. They are typically differentiated based on software and incremental design costs must be kept low. The aim of this research is to develop an efficient design flow for this class of systems. We start with a Kahn Process Network (KPN) specification of the application and a model of the architectural platform. Then, we progress toward implementation in a series of well-defined steps to ensure that we can obtain efficient results with tractable complexity. Reconfiguration Architectural Platform Description Kahn Process Network Specification Step 4: Deadlock Detection & Resolution Allocation of Computational &Communication Resources • Static determination of channel sizes is not sufficient to guarantee freedom from artificial deadlock situations • Synthesize and allocate an extra runtime manager in the system to detect instances of deadlock • Also synthesize strategies to allocate extra storage to channels to resolve this deadlock • Runtime manager is specialized for the structure and behavior of the KPN Initial Sizing of CommunicationChannels Step 1: Reconfiguration Runtime Deadlock Detection& Resolution Algorithms • Through analysis of the KPN specification or using simulation, estimate concurrency and communication requirements • If architectural model is reconfigurable, choose a restricted set of configurations based on application requirements • Based on architectural constraints, possibly merge or split functional processes while not changing the functionality Picture-in-Picture Case Study Case study involves mapping between a digital television application and a heterogeneous multiprocessor architecture for a set-top box system Architectural Platform Functional Model Step 2: Allocation CustomProc GPProc USRCONTROL MEM MEM • Decompose the services utilized by the functional model and the services provided by the arch. platform into a Common Semantic Domain • The allocation problem then reduces to a covering problem • The covering problem can be solved by estimated the intensities of service usage by the functional model and the affinities for the corresponding services in the arch. platform PIP RESIZE MPEG BUS DEMUX PARSER JUGGLER GlobalMemory GPProc MEM MPEG November 18, 2004