Architecture Modeling - SPES 2020

Architecture Modeling
Design processes can then be described as trajectories in a two-dimensional design space
spanned by abstraction levels as horizontal dimensions and the three perspectives focussing on
behavior, architecture, and geometry as vertical dimensions. Typical steps include:
• Synthesis: This starts with a behavior specification on level N and produces a technical
architecture on level N-1, i. e. shows how primitives of level N-1 can be interconnected to
realize the level-N behavior specification by combining the lower level components based
as prescribed in the level-(N-1) architecture.
• Analysis: Takes a level-(N-1) netlist and “computes” the emergent behavior at level N.
• Implementation: Shows how to realize a level-N component in the physical domain.
• Integration (placement and routing): Combines level-(N-1) layouts of level-(N-1) components
according to a level-(N-1) architecture to build an implementation of a level-N
component.
In platform based design, we pick some abstraction level N as design basis, and assume as
given a library of level-N components, where each library element is given in all three perspectives
and characterized w.r.t. all aspects required for a complete automation of the design
processes (e. g. required voltage levels, leak currents, propagation delays etc). The determination
of the design basis comes from trade-off analysis involving costs, performance, design
time, etc. Clearly, lowering the design basis allows higher levels of optimization, at the price
of increased design time. Hence, even for one and the same application, the actual design
process will be determined by business constraints. Moreover, this shows the need to address
both library design and application design. We finally notice, that the degree of automation of
synthesis and analysis steps is increasing when moving to lower abstraction layers, as does the
automation of placement and routing. Implementations today are largely either given by design
libraries or derived with placement and routing. In incremental design, only parts of the system
are re-designed, in a way striving to minimize the impact of this re-design on the surrounding
components. Standardization and in particular standardized bus systems and interfaces are key
instruments allowing to completely localize the effect of such component replacements.
All of these have contributed to an exponential productivity boost in the EDA domain, allowing
so far (by adding higher and higher abstraction levels, such as Transaction Level Modeling)
to compensate the exponential growth in functionality realized in integrated circuits.
5.1.1.1 What We Want to Achieve for Embedded-Systems Based Product Development
We expect to achieve similarly productive boosts for embedded-system design through the introduction
of the architecture meta-model based on abstraction layers and perspectives in combination
with the contract-based multi-aspect component based design technique of Hierarchical
Rich Components, which allows to build design libraries at any abstraction layer, supporting all
phases of embedded systems product development. The large number of domain specific standardization
activities in Embedded Systems design (such as AUTOSAR, IMA) gives clear evidence
of the industrial drive to boost productivity through standardized interfaces, standardized
meta-models, and standardization of non-differentiating design components. Different design
styles (or, in “our” jargon, different design processes) can again be captured by different trajectories
in this richer design space. Concepts such as platform based design, synthesis, placement
and routing, etc., have natural counterparts. For the geometric domain, vendors of CAD and
PLM tool suites have gone a long way in providing industry strength design automation support,
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