ESE 566: HardwareSoftware CoDesign of Embedded Systems Fall 2005 Instructor: Dr' Alex Doboli'

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ESE 566 Hardware/Software Co-Design of Embedded
SystemsFall 2005 Instructor Dr. Alex Doboli.

• Paper discussed in class R. Ernst, J. Henkel, T.
  Benner, Hardware-Software Cosynthesis of
  Microcontrollers, IEEE Design Test of
  Computers, Vol. 10, No, 4, December 1993, pp.
  64-75.

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Brief description of the paper content

• What is the paper discussing?

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The context of the work

• What kind of applications are the authors
  considering?
• What kind of architecture are the authors
  considering?
• What existing limitations are addressed in this
  work? Are these limitations still there?

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The context of the work

• What other alternative solutions exist to this
  problem?
• How would you compare the proposed solution to
  the alternative solutions?
• Do you think that the approach could be used for
  other types of applications also?

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Description of the proposed solution

• Summarize the solution proposed by the authors.
• What is the methodology? What performance
  constraints are the authors considering? What is
  the target architecture for their implementation?

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Description of the proposed solution

• What is the methodology? What kind of
  descriptions fit the methodology
  (control-driven/data-driven/mixture of data
  control/memory centric)? What is the target
  architecture for their implementation?
• What activities are part of their design solution?

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Description of the proposed solution

• What are the claims of this work?
• What are the limitations of the approach? Do you
  think that these limitations can be solved?

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Related work

• What similar work are the authors discussing?
  Does this work have fundamental differences or is
  it just a different technique? What are the
  advantages of this method over similar work? What
  are the limitations? Summarize the different
  approaches mentioned in the paper.

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The Cosynthesis Methodology

• What is partitioning? At what level of
  granularity is partitioning performed? What
  issues must be considered?
• Explain the cosynthesis methodology? Inputs
  outputs design activities. What is the
  granularity of the design? Why? Do you see a
  different way of organizing the flow? Does the
  methodology rely on other design tools? Do you
  see a limitation in this methodology?

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System Modeling

• How is the system modeled? What is the
  granularity of the description (tasks/blocks/instr
  uctions/operations)?What language constructs are
  needed? What language constructs cannot be
  handled? Are these limitations important? Do you
  see a solutions to address these limitations?

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Extended-Syntax Graph

• What is an intermediate representation? Why do we
  need an intermediate representation for (why not
  just the input specification)?
• What are the characteristics of ES Graphs? What
  design activities are the characteristics useful
  for?
• Is there any way you would improve ES Graphs?

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Hardware/software Partitioning

• How are the obtained hardware-software
  implementations executed? Is this correct in
  real-life? Is there any link between the
  execution model and the cosynthesis methodology?
• Present the hardware-software partitioning method
  

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Hardware/software Partitioning

• Simulated Annealing algorithm
• Cost function for SA. Describe the cost function.
  How do you validate your cost function?

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Hardware/software Partitioning

• Profiling what data is collected through
  profiling? What can you predict using this data
  (functionality, communication, performance)? What
  can you not predict using this data?
• How is data communicated between processor and
  co-processor? How is communication cost
  evaluated? Why is communication difficult to
  evaluate? What elements are not considered in the
  current evaluation method?

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Target Architecture

• Detail the hardware architecture.

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Experiments

• Experimental set-up What experiments were
  performed? What was the benchmark? What was
  observed? Are these experiments sufficient to
  support the paper claims? What other design tools
  did the authors use?
• What results were obtained? What was observed?
  What unexpected results have been seen?

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Discussions

• What are the limitations of the approach?
• Summarize the work and its merit.
• Ideas for improving the work?