Design & Co design of Embedded SystemsDesign & Co-design of Embedded Systems

Lecture 1:

Introduction to Digital System Design & C D iCo-Design

Computer Engineering Dept.Sharif University of Technology

Winter-Spring 2008

Mehdi Modarressi

Topics for Today

Evolution of Digital-Design MethodologiesEvolution of Digital Design MethodologiesIntroduction to Hw/Sw Co-Design

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Chip Design EvolutionChip Design Evolution

Moore’s Law: Chip densities would double every 12–18 months.

The first IC (1958-TI) 4 transistors, 50$ !

The first microprocessor(1971-Intel)2300 transistors, 108 KHz

Mi T dMicroprocessors Today:Intel Core2 Quad: 580 M. transistors- 2.4 GHzIntel Quad-core 64b Itanium: 2 B. transistors.

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Evolution of Digital Design MethodsTransistor Netlist 1970’s

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Evolution of DDM (cont.)RT level: Register Transfer level, Schematic 1980’s

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Evolution of DDM (cont.)BL: Behavioral Level, HDL: Hardware Description Language, 1990’s

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Digital System Design

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Embedded Systems

Embedded vs. Self-ContainedEmbedded vs. Self Contained Systems Embedded computing systems

Computers are in here...

and here...

Computing systems embedded within electronic devicesHard to define Nearly any computing

and even here...

Hard to define. Nearly any computing system other than a desktop computer79% of all Produced Digital systemsPerhaps 100s per household and per automobile

Lots more of these, though they cost a lot

less each.

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Today’s Embedded Systems

Increasing application complexityg pp p y

Mixture of several tasks (event driven and data flow) Examples: multimedia automotive mobile communicationExamples: multimedia, automotive, mobile communication

Increasing target system complexityMixture of different technologies, processor types, and design stylesLarge systems-on-a-chip, distributed systemsUp to 2 billion trans. on a single chip , 75 million in common processors.

Non-functional requirements are important

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Non functional requirements are important

Functional vs. Non-Functional Requirements

Functional requirements:Functional requirements:Output as a function of input.

Non-functional requirements:Time required to compute output;Size, weight, etc.;Power consumption;Reliability;Reliability;etc.

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System-level Design

M hi h b t ti l lMore higher abstraction level:System-level design

System = HW components +SW modulesSystem = HW components +SW modules

Describe the system functionality regardless ofDescribe the system functionality regardless of (hw/sw) implementation typePartition the design into hardware and software gmodules based on the non-functional requirements

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Hardware /Software Realization

Hardware and software are functionally equivalent :Any Software realizable algorithm can be realized in hardware as well andAny Software-realizable algorithm can be realized in hardware as well, and vice versa.

How much SW + how much HW? Determined by non-functional requirementsrequirements.

Hardware Realization Software RealizationSpeedEnergy EfficiencyC t Effi i (b t i

FlexibilityEase of DevelopmentEase of Test and DebugCost Efficiency (but in

high volumes)Ease of Test and DebugCost = SW + Processor

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More Complexities in Hardware/Software Realization

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Design Problem

H t l t h d / ftHow to select a hardware/software implementation out of the design space to meet Functional and Non functional designmeet Functional and Non-functional design goals?

Hardware-Software Co-design

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Co-design Main TopicsSynthesis

System H S

System

VerificationSpecification

OS

VerificationSpecification

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SystemSpecification

Verification

Co-SynthesisPartitioning

HW ParameterEstimation

SW ParameterEstimation

Verification

Estimation Estimation

SW SynthesisHW SynthesisVerification

SW SynthesisHW Synthesis

ASIC OS

VerificationEXE Code

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SystemIntegration Final Verification

Co-design Main Topics

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Hardware/Software Partitioning

How functionality is separated between HW and SW blocks

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Application Mapping

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Task Scheduling

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Hardware Synthesis

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Software Compilation

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What we learned today

Digital design methods are moving toward higher abstractionsH d d ft f ti l i l tHardware and software are functional equivalentNon-functional requirements determine HW/SW implementationHw/Sw co-design stages

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Next Session Topics

Introduction to embedded systemsIntroduction to embedded systemsPropertiesRequirementsRequirementsDesign issues

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