MARTE/CCSL, TimeSquare

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MARTE/CCSL,TimeSquare K-PassaA design
platform using MoCCs for embedded model-based
engineering

• C. André, J. Boucaron, A. Coadou, J. DeAntoni,
• B. Ferrero, F. Mallet, R. de Simone
• AOSTE Project INRIA/I3S
• Sophia Antipolis, France

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Context

• Modeling environments for real-time embedded and
  distributed systems

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Context

• Modeling environments for real-time embedded and
  distributed systems
• Conceptual diagrammatic representations
• Structural
• Components / interactions
• Dynamics/Behavior

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Context

• Modeling environments for real-time embedded and
  distributed systems
• Conceptual diagrammatic representations
• Structural
• Components / interactions
• Dynamics/Behavior of individual components
• State-based control flow
• Activity-based data flow
• Constrained programs with same expressivity

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Context

• Modeling environments for real-time embedded and
  distributed systems
• Conceptual diagrammatic representations
• Structural
• Components / interactions
• Dynamics/Behavior of individual components
• State-based control flow
• Activity-based data flow
• Constrained programs with same expressivity
• Dynamics/Behavior of system
• results from combining component behaviors
  according to structure

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Example of architecture modeling
Structure
Behavior
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Example of architecture modeling
Structure
Behavior
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Example of architecture modeling
Structure
Elaboration phase (SystemC)
Behavior
Simulation
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Traditional component approach

• Structure
• Black-box Interfaces (Ports, Data Types)
• Behavioral abstraction
• Messages possibly period and performance
  requirements
• What we find missing
• Detailed definition of timing and synchronization
  properties
• Communication protocol requirements
• This missing information is often deported
  elsewhere

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Traditional component approach

• Structure
• Black-box Interfaces (Ports, Data Types)
• Behavioral abstraction
• Messages possibly period and performance
  requirements
• What we find missing
• Detailed definition of timing and synchronization
  properties
• Communication protocol requirements
• This missing information is often deported
  elsewhere

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Time Semantics

• physical time
• Extra functional
• Single time (total order)
• Timing constraints to be satisfied at execution
• Simulation semantics possibly different from
  synthesis
• UML, SystemC

• Logical functional time
• Functional sequence of reaction steps
• Multiple times (local / global)
• Synchronization primitives ? constraints between
  local activation times
• Synthesis / Compilation
• Process networks (SDF), synchronous reactive
  formalisms, statecharts

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Time Semantics

• physical time
• Extra functional
• Single time (total order)
• Timing constraints to be satisfied at execution
• Simulation semantics possibly different from
  synthesis
• UML, SystemC

• Logical functional time
• Functional sequence of reaction steps
• Multiple times (local / global)
• Synchronization primitives ? constraints between
  local activation times
• Synthesis / Compilation
• Process networks (SDF), synchronous reactive
  formalisms, statecharts

HDLs
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Semantics

• physical time
• Extra functional
• Single time (total order)
• Timing constraints to be satisfied at execution
• Simulation semantics possibly different from
  synthesis
• UML, SystemC

• Logical functional time
• Functional sequence of reaction steps
• Multiple times (local / global)
• Synchronization primitives ? constraints between
  local activation times
• Synthesis / Compilation
• Process networks (SDF), synchronous reactive
  formalisms, statecharts

Our choice
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MARTE Time model and CCSL

• MARTE Modeling and Analysis of Real-Time and
  Embedded systems
• OMG UML profile (adopted June 2009)
• Time subprofile (defined by us)
• Rich but well-defined variety of time notions
  (logical/physical, discrete/dense, )
• Clocks can be explicitly attached to most UML
  model elements ? timed semantics
• Clock Constraint Specification Language (CCSL)
• Various constraints on clocks (synchronous,
  asynchronous, mixed)
• Precise formal semantics

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Why CCSL?

• Polychronous system modeling
• Specification of sophisticated synchronizations
• Notation to describe semantic relations between
  timed behaviors (illustrated below)
• Means to define formally timed Models of
  Computations and Communications (MoCCs)
• Akin to Tagged Systems (Lee Sangiovanni-Vincente
  lli)

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Why CCSL?

• Means to define formally timed Models of
  Computations and Communications (MoCCs)
• In the sequel, we translate a MoCC as UML models
  CCSL specifications
• The chosen MoCC is SDF (weighted event graphs)
  models

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Synchronous DataFlow
SDF Meta-model

• Nodes are called actors
• Input/Output have a weight (Number of data
  samples consumed/produced)
• Arcs have a delay

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Synchronous DataFlow
SDF firing rules

• Actor enabling each incoming arc carries at
  least weight tokens
• Actor execution atomic consumption/production
  of tokens by an enabled actor
• i.e., consume weight tokens on each incoming arcs
  and produce weight tokens on each outgoing arc
• Delay is an initial token load on an arc.

How can CCSL express this semantics?
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SDF Example
Evolutions of the model
A
A
B
A
A
B
Static schedule
C
C
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How to model SDF graphs in UML ?
Is that compatible with the UML semantics ? CCSL
makes the semantics explicit
within the model
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SDF semantics with CCSL (1/2)

• SDF
• Actor A
• Token T
• Input i
• Output o

• CCSL
• Clock A
• Clock write, read
• Var delayint
• Var weightint
• Var weightint

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SDF semantics with CCSL (2/2)

• SDF
• CCSL

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Example
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TimeSquare
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AOSTEs Tools

• TimeSquare
• Software environment dedicated to the
• Specification of CCSL constraints
• Resolution of CCSL constraints
• Simulation and generation of trace model
• Animation of UML models
• Exploration of augmented timing diagrams
• K-Passa
• Computation of static schedules for specific
  MoCCs
• Marked Graphs, Synchronous DataFlow,
  Latency-Insensitive Designs, K-periodical Routed
  Graphs
• Analysis (deadlock freeness, safety)
• Optimization (latency, throughput, interconnect
  buffer size)
• Code generation (stand-alone simulator)

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K-Passa
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Tool download

• http//www-sop.inria.fr/aoste/

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Thank you All