大規模システムLSI設計のための統一的ハードウェア・ソフトウェア協調検証手法

Currently, the complexity of embedded LSI system is growing faster than the productivity of system design. This trend results in a design productivity gap, particularly in tight development time. Since the verification task takes bigger part of development task, it becomes a major challenge in LSI system design. In order to guarantee system reliability and quality of results (QoR), verifying large coverage of system functionality requires huge amount of relevant test cases and various scenario of evaluations. To overcome these problems, verification methodology is evolving toward supporting higher level of design abstraction by employing HW-SW co-verification. In this study, we present a novel approach for verification LSI circuit which is called as unified HW/SW co-verification framework. The study aims to improve design efficiency while maintains implementation consistency in the point of view of system-level performance. The proposed data-driven simulation and flexible interface of HW and SW design become the backbone of verification framework. In order to avoid time consuming, prone error, and iterative design spin-off in a large team, the proposed framework has to support multiple design abstractions. Hence, it can close the loop of design, exploration, optimization, and testing. Furthermore, the proposed methodology is also able to co-operate with system-level simulation in high-level abstraction, which is easy to extend for various applications and enables fast-turn around design modification. These contributions are discussed in chapter 3. In order to show the effectiveness and the use-cases of the proposed verification framework, the evaluation and metrics assessments of Very High Throughput wireless LAN system design are carried out. Two application examples are provided. The first case in chapter 4 is intended for fast verification and design exploration of large circuit. The Maximum Likelihood Detection (MLD) MIMO decoder is considered as Design Under Test (DUT). The second case, as presented in chapter 5, is the evaluation for system-level simulation. The full transceiver system based on IEEE 802.11ac standard is employed as DUT. Experimental results show that the proposed verification approach gives significant improvements of verification time (e.g. up to 10,000 times) over the conventional scheme. The proposed framework is also able to support various schemes of system level evaluations and cross-layer evaluation of wireless system.九州工業大学博士学位論文 学位記番号：情工博甲第328号 学位授与年月日：平成29年6月30日1 Introduction|2 Design and Verification in LSI System Design|3 Unified HW/SW Co-verification Methodology|4 Fast Co-verification and Design Exploration in Complex Circuits|5 Unified System Level Simulator for Very High Throughput Wireless Systems|6 Conclusion and Future Work九州工業大学平成29年

Unbounded Scalable Hardware Verification.

Model checking is a formal verification method that has been successfully applied to real-world hardware and software designs. Model checking tools, however, encounter the so-called state-explosion problem, since the size of the state spaces of such designs is exponential in the number of their state elements. In this thesis, we address this problem by exploiting the power of two complementary approaches: (a) counterexample-guided abstraction and refinement (CEGAR) of the design's datapath; and (b) the recently-introduced incremental induction algorithms for approximate reachability. These approaches are well-suited for the verification of control-centric properties in hardware designs consisting of wide datapaths and complex control logic. They also handle most complex design errors in typical hardware designs. Datapath abstraction prunes irrelevant bit-level details of datapath elements, thus greatly reducing the size of the state space that must be analyzed and allowing the verification to be focused on the control logic, where most errors originate. The induction-based approximate reachability algorithms offer the potential of significantly reducing the number of iterations needed to prove/disprove given properties by avoiding the implicit or explicit enumeration of reachable states. Our implementation of this verification framework, which we call the Averroes system, extends the approximate reachability algorithms at the bit level to first-order logic with equality and uninterpreted functions. To facilitate this extension, we formally define the solution space and state space of the abstract transition system produced by datapath abstraction. In addition, we develop an efficient way to represent sets of abstract solutions involving present- and next-states and a systematic way to project such solutions onto the space of just the present-state variables. To further increase the scalability of the Averroes verification system, we introduce the notion of structural abstraction, which extends datapath abstraction with two optimizations for better classification of state variables as either datapath or control, and with efficient memory abstraction techniques. We demonstrate the scalability of this approach by showing that Averroes significantly outperforms bit-level verification on a number of industrial benchmarks.PhDComputer Science and EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/133375/1/suholee_1.pd

Formal Power Analysis of Systems-on-Chip

The design methods and languages targeted to modern System-on-Chip designs are facing tremendous pressure of the ever-increasing complexity, power, and speed requirements. To estimate any of these three metrics, there is a trade-off between accuracy and abstraction level of detail in which a system under design is analyzed. The more detailed the description, the more accurate the simulation will be, but, on the other hand, the more time consuming it will be. Moreover, a designer wants to make decisions as early as possible in the design flow to avoid costly design backtracking. To answer the challenges posed upon System-on-chip designs, this thesis introduces a formal, power aware framework, its development methods, and methods to constraint and analyze power consumption of the system under design. This thesis discusses on power analysis of synchronous and asynchronous systems not forgetting the communication aspects of these systems. The presented framework is built upon the Timed Action System formalism, which offer an environment to analyze and constraint the functional and temporal behavior of the system at high abstraction level. Furthermore, due to the complexity of System-on-Chip designs, the possibility to abstract unnecessary implementation details at higher abstraction levels is an essential part of the introduced design framework. With the encapsulation and abstraction techniques incorporated with the procedure based communication allows a designer to use the presented power aware framework in modeling these large scale systems. The introduced techniques also enable one to subdivide the development of communication and computation into own tasks. This property is taken into account in the power analysis part as well. Furthermore, the presented framework is developed in a way that it can be used throughout the design project. In other words, a designer is able to model and analyze systems from an abstract specification down to an implementable specification.Siirretty Doriast

Decompose and Conquer: Addressing Evasive Errors in Systems on Chip

Modern computer chips comprise many components, including microprocessor cores, memory modules, on-chip networks, and accelerators. Such system-on-chip (SoC) designs are deployed in a variety of computing devices: from internet-of-things, to smartphones, to personal computers, to data centers. In this dissertation, we discuss evasive errors in SoC designs and how these errors can be addressed efficiently. In particular, we focus on two types of errors: design bugs and permanent faults. Design bugs originate from the limited amount of time allowed for design verification and validation. Thus, they are often found in functional features that are rarely activated. Complete functional verification, which can eliminate design bugs, is extremely time-consuming, thus impractical in modern complex SoC designs. Permanent faults are caused by failures of fragile transistors in nano-scale semiconductor manufacturing processes. Indeed, weak transistors may wear out unexpectedly within the lifespan of the design. Hardware structures that reduce the occurrence of permanent faults incur significant silicon area or performance overheads, thus they are infeasible for most cost-sensitive SoC designs. To tackle and overcome these evasive errors efficiently, we propose to leverage the principle of decomposition to lower the complexity of the software analysis or the hardware structures involved. To this end, we present several decomposition techniques, specific to major SoC components. We first focus on microprocessor cores, by presenting a lightweight bug-masking analysis that decomposes a program into individual instructions to identify if a design bug would be masked by the program's execution. We then move to memory subsystems: there, we offer an efficient memory consistency testing framework to detect buggy memory-ordering behaviors, which decomposes the memory-ordering graph into small components based on incremental differences. We also propose a microarchitectural patching solution for memory subsystem bugs, which augments each core node with a small distributed programmable logic, instead of including a global patching module. In the context of on-chip networks, we propose two routing reconfiguration algorithms that bypass faulty network resources. The first computes short-term routes in a distributed fashion, localized to the fault region. The second decomposes application-aware routing computation into simple routing rules so to quickly find deadlock-free, application-optimized routes in a fault-ridden network. Finally, we consider general accelerator modules in SoC designs. When a system includes many accelerators, there are a variety of interactions among them that must be verified to catch buggy interactions. To this end, we decompose such inter-module communication into basic interaction elements, which can be reassembled into new, interesting tests. Overall, we show that the decomposition of complex software algorithms and hardware structures can significantly reduce overheads: up to three orders of magnitude in the bug-masking analysis and the application-aware routing, approximately 50 times in the routing reconfiguration latency, and 5 times on average in the memory-ordering graph checking. These overhead reductions come with losses in error coverage: 23% undetected bug-masking incidents, 39% non-patchable memory bugs, and occasionally we overlook rare patterns of multiple faults. In this dissertation, we discuss the ideas and their trade-offs, and present future research directions.PHDComputer Science & EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/147637/1/doowon_1.pd

Methoden und Beschreibungssprachen zur Modellierung und Verifikation vonSchaltungen und Systemen: MBMV 2015 - Tagungsband, Chemnitz, 03. - 04. März 2015

Der Workshop Methoden und Beschreibungssprachen zur Modellierung und Verifikation von Schaltungen und Systemen (MBMV 2015) findet nun schon zum 18. mal statt. Ausrichter sind in diesem Jahr die Professur Schaltkreis- und Systementwurf der Technischen Universität Chemnitz und das Steinbeis-Forschungszentrum Systementwurf und Test. Der Workshop hat es sich zum Ziel gesetzt, neueste Trends, Ergebnisse und aktuelle Probleme auf dem Gebiet der Methoden zur Modellierung und Verifikation sowie der Beschreibungssprachen digitaler, analoger und Mixed-Signal-Schaltungen zu diskutieren. Er soll somit ein Forum zum Ideenaustausch sein. Weiterhin bietet der Workshop eine Plattform für den Austausch zwischen Forschung und Industrie sowie zur Pflege bestehender und zur Knüpfung neuer Kontakte. Jungen Wissenschaftlern erlaubt er, ihre Ideen und Ansätze einem breiten Publikum aus Wissenschaft und Wirtschaft zu präsentieren und im Rahmen der Veranstaltung auch fundiert zu diskutieren. Sein langjähriges Bestehen hat ihn zu einer festen Größe in vielen Veranstaltungskalendern gemacht. Traditionell sind auch die Treffen der ITGFachgruppen an den Workshop angegliedert. In diesem Jahr nutzen zwei im Rahmen der InnoProfile-Transfer-Initiative durch das Bundesministerium für Bildung und Forschung geförderte Projekte den Workshop, um in zwei eigenen Tracks ihre Forschungsergebnisse einem breiten Publikum zu präsentieren. Vertreter der Projekte Generische Plattform für Systemzuverlässigkeit und Verifikation (GPZV) und GINKO - Generische Infrastruktur zur nahtlosen energetischen Kopplung von Elektrofahrzeugen stellen Teile ihrer gegenwärtigen Arbeiten vor. Dies bereichert denWorkshop durch zusätzliche Themenschwerpunkte und bietet eine wertvolle Ergänzung zu den Beiträgen der Autoren. [... aus dem Vorwort

Timing properties in real-time systems

This dissertation proposes a formalism for the specification and verification of timing properties of real-time systems. Reasoning about properties of a real-time system requires one to consider both relative and absolute timing of events. Relative timing concerns the order in which events occur, such as mutual exclusion and precedence constraint properties. Absolute timing concerns the stringent timing restrictions imposed on a system, such as a response time deadline or a minimum elapsed time between occurrences of two events. The approach is based on Real Time Logic (RTL), a logic invented primarily for the specification of both relative and absolute timing of events. The notion of an event occurrence is central to RTL; an event occurrence marks a point in time which is of significance to the behavior of a system. Hence, concurrency is modeled as a partial ordering of the event occurrences in the system. A system specification and a property to be verified can be expressed as arithmetical relations on algebraic expressions involving the event occurrences. To verify the property with respect to the system specification, we prove that the property is a theorem derivable from the specification. Relationship of RTL to Presburger Arithmetic is discussed and a verification technique based on inequality provers is explored. The dissertation also introduces a specification language, Modechart, for real-time systems. The semantics of Modechart is described in terms of RTL formulas. In Modechart, we make use of the concept of modes which can be thought of as partitioning the state space of a system. Intuitively, modes can be viewed as control information that impose structure on the operation of a system. Modes are arranged hierarchically. Furthermore, modes at the same level of hierarchy can be related in one of two ways: in series or in parallel. A transition can be specified between two modes in series, but no transition is allowed between modes in parallel. The language allows sporadic/periodic actions in modes as well as constructs for specifying timing constraints such as delays and deadlines on mode transitions. Verification procedures are introduced for showing a Modechart specification satisfies a property expressed as an RTL formula.Computer Science

Proceedings of the 22nd Conference on Formal Methods in Computer-Aided Design – FMCAD 2022

The Conference on Formal Methods in Computer-Aided Design (FMCAD) is an annual conference on the theory and applications of formal methods in hardware and system verification. FMCAD provides a leading forum to researchers in academia and industry for presenting and discussing groundbreaking methods, technologies, theoretical results, and tools for reasoning formally about computing systems. FMCAD covers formal aspects of computer-aided system design including verification, specification, synthesis, and testing

Tools and Algorithms for the Construction and Analysis of Systems

This open access two-volume set constitutes the proceedings of the 27th International Conference on Tools and Algorithms for the Construction and Analysis of Systems, TACAS 2021, which was held during March 27 – April 1, 2021, as part of the European Joint Conferences on Theory and Practice of Software, ETAPS 2021. The conference was planned to take place in Luxembourg and changed to an online format due to the COVID-19 pandemic. The total of 41 full papers presented in the proceedings was carefully reviewed and selected from 141 submissions. The volume also contains 7 tool papers; 6 Tool Demo papers, 9 SV-Comp Competition Papers. The papers are organized in topical sections as follows: Part I: Game Theory; SMT Verification; Probabilities; Timed Systems; Neural Networks; Analysis of Network Communication. Part II: Verification Techniques (not SMT); Case Studies; Proof Generation/Validation; Tool Papers; Tool Demo Papers; SV-Comp Tool Competition Papers

A generic debug interface for IP-integrated assertions

Der Entwurf von Hardware/Software Systemen ist auf eine solide Verifikationsmethodik angewiesen, die den ganzen Design Flow durchzieht. Viele Konzepte haben eine Erhöhung des Abstraktionsniveaus bei der Entwurfseingabe gemeinsam, wobei der modell-basierte Hardware-Entwurf einen vielversprechenden und sich verbreitenenden Ansatz darstellt. Assertion basierte Verifikation ermöglicht dem Entwickler die Spezifikation von Eigenschaften des Entwurfes und die Aufdeckung von Fällen, in denen diese verletzt werden. Während Assertions in Entwurfs- und Simulationsstadien weit verbreitet sind, ist der Ansatz, diese mit auf dem integrierten Schaltkreis (IC) zu fertigen, neuartig. In dieser Diplomarbeit soll ein von Infineon Technologies entwickeltes, auf UML basierendes Datenmodell, welches zur Erfassung von Entwurfsspezifikation und zur automatischen Code-Generierung genutzt wird dahingehend erweitert werden, die Beschreibung für im IC integrierte Assertions zu ermöglichen. Für diese Zwecke wird ein abstraktes Datenmodell beschrieben werden. Das Assertion Interface soll die spezifikationsgetreue Modellintegration gewährleisten, sowie IC interne Assertionresultate dem umgebenen System über das Interface zugänglich machen und damit zum Debugging während der Laufzeit ermöglichen. Ferner werden die Codegenerierungs Templates erläutert und einBeispielsystem eingeführt, um die beschriebenden Konzepte zu validieren.Nowadays electronic systems design requires fast time to market and solid verification throughout the entire design flow. Many concepts have been researched to raise the level of abstraction during the design entry phase, whereas model-based design is the most promising one. Assertion-based verification enables the developer to specify properties of the design and to get report if these are violated. Assertions are common during development and simulation of electronic products but often are not included in the final silicon. In this thesis an UML-based model defined at Infineon Technologies for capturing design specification information and to generate code automatically using templates, will be extended to allow the description of an abstract debuggable assertion interface for silicon assertions. With help of the assertion interface it shall be possible to verify the correct module integration and to monitor IP-internal assertion checker results. Besides, the code-generation templates for the assertion interface model will be described. To demonstrate the usability of the developed concepts an example system will be introduced to validate the approach.Ilmenau, Techn. Univ., Diplomarbeit, 200