C for a Tiny System Implementing C for a Tiny System and Making the Architecture More Suitable for C
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Antikernel: a Decentralized Secure Hardware-Software Operating
Antikernel A Decentralized Secure Hardware-Software Operating System Andrew Zonenberg (@azonenberg) Senior Security Consultant, IOActive Bülent Yener Professor, Rensselaer Polytechnic Institute This work is based on Zonenberg’s 2015 doctoral dissertation, advised by Yener. IOActive, Inc. Copyright ©2016. All Rights Reserved. Kernel mode = full access to all state • What OS code needs this level of access? – Memory manager only needs heap metadata – Scheduler only needs run queue – Drivers only need their peripheral – Nothing needs access to state of user-mode apps • No single subsystem that needs access to all state • Any code with ring 0 privs is incompatible with LRP! IOActive, Inc. Copyright ©2016. All Rights Reserved. Monolithic kernel, microkernel, … Huge Huge attack surface Small Better 0 code size - Ring Can we get here? None Monolithic Micro ??? IOActive, Inc. Copyright ©2016. All Rights Reserved. Exokernel (MIT, 1995) • OS abstractions can often hurt performance – You don’t need a full FS to store temporary data on disk • Split protection / segmentation from abstraction Word proc FS Cache Disk driver DHCP server IOActive, Inc. Copyright ©2016. All Rights Reserved. Exokernel (MIT, 1995) • OS does very little: – Divide resources into blocks (CPU time quanta, RAM pages…) – Provide controlled access to them IOActive, Inc. Copyright ©2016. All Rights Reserved. But wait, there’s more… • By removing non-security abstractions from the kernel, we shrink the TCB and thus the attack surface! IOActive, Inc. Copyright ©2016. All Rights Reserved. So what does the kernel have to do? • Well, obviously a few things… – Share CPU time between multiple processes – Allow processes to talk to hardware/drivers – Allow processes to talk to each other – Page-level RAM allocation/access control IOActive, Inc. -
Mali-400 MP: a Scalable GPU for Mobile Devices
Mali-400 MP: A Scalable GPU for Mobile Devices Tom Olson Director, Graphics Research, ARM Outline . ARM and Mobile Graphics . Design Constraints for Mobile GPUs . Mali Architecture Overview . Multicore Scaling in Mali-400 MP . Results 2 About ARM . World’s leading supplier of semiconductor IP . Processor Architectures and Implementations . Related IP: buses, caches, debug & trace, physical IP . Software tools and infrastructure . Business Model . License fees . Per-chip royalties . Graphics at ARM . Acquired Falanx in 2006 . ARM Mali is now the world’s most widely licensed GPU family 3 Challenges for Mobile GPUs . Size . Power . Memory Bandwidth 4 More Challenges . Graphics is going into “anything that has a screen” . Mobile . Navigation . Set Top Box/DTV . Automotive . Video telephony . Cameras . Printers . Huge range of form factors, screen sizes, power budgets, and performance requirements . In some applications, a huge difference between peak and average performance requirements 5 Solution: Scalability . Address a wide variety of performance points and applications with a single IP and a single software stack. Need static scalability to adapt to different peak requirements in different platforms / markets . Need dynamic scalability to reduce power when peak performance isn’t needed 6 Options for Scalability . Fine-grained: Multiple pipes, wide SIMD, etc . Proven approach, efficient and effective . But, adding pipes / lanes is invasive . Hard for IP licensees to do on their own . And, hard to partition to provide dynamic scalability . Coarse-grained: Multicore . Easy for licensees to select desired performance . Putting cores on separate power islands allows dynamic scaling 7 Mali 400-MP Top Level Architecture Asynch Mali-400 MP Top-Level APB Geometry Pixel Processor Pixel Processor Pixel Processor Pixel Processor Processor #1 #2 #3 #4 CLKs MaliMMUs RESETs IRQs IDLEs MaliL2 AXI . -
Versa 8051 Mcus TB102 – Using Versa 8051 Include Files Rev 1.0
Versa 8051 MCUs TB102 – Using Versa 8051 Include Files Rev 1.0 How to Use Include Files for Versa 8051 MCUs 1 Introduction For compilers/assemblers that do not allow long file names, the naming convention is as follows: This technical bulletin addresses the include files developed for each of Ramtron’s fast and flexible AAFFDDDD.EXT Versa 8051 microcontrollers. Include files contain code AA: The initials of the compiler or assembler, such as for the MCU’s special function registers (SFRs). This ML for the MetaLink Cross Assembler. code is compatible with most popular 8051 compilers and assemblers. FF: The family of the target device: RS for the Versa 8051 family. 2 Supported Compilers DDDD: The first digit grouping of the device name, for Currently, include files exist for the following 8051 example the VRS51L2070 will use 2070. compilers and assemblers: EXT: The extension for the target programming language, such as .H for the C language, or .inc for an • MetaLink Macro Assembler assembler. • RIDE 51 (RKit) MA51 Macro Assembler • RIDE 51 (RKit) RC51 C Compiler 3.2 Location and Installation • Keil µVision3 A51 Macro Assembler All the files are placed in a zipped folder labeled with • Keil µVision3 C51 C Compiler the device name (for example, VRS51L3074.ZIP). • SDCC (Small Device C Compiler) When downloaded, the necessary file(s) can be moved • ASX8051 cross assembler to two possible locations: If you are using a different compiler, apply one of the • The compiler/assembler source directory provided files as a template or contact Ramtron for • The folder of the current project assistance. -
Nyami: a Synthesizable GPU Architectural Model for General-Purpose and Graphics-Specific Workloads
Nyami: A Synthesizable GPU Architectural Model for General-Purpose and Graphics-Specific Workloads Jeff Bush Philip Dexter†, Timothy N. Miller†, and Aaron Carpenter⇤ San Jose, California †Dept. of Computer Science [email protected] ⇤ Dept. of Electrical & Computer Engineering Binghamton University {pdexter1, millerti, carpente}@binghamton.edu Abstract tempt to bridge this gap, Intel developed Larrabee (now called Graphics processing units (GPUs) continue to grow in pop- Xeon Phi) [25]. Larrabee is architected around small in-order ularity for general-purpose, highly parallel, high-throughput cores with wide vector ALUs to facilitate graphics rendering and systems. This has forced GPU vendors to increase their fo- multi-threading to hide instruction latencies. The use of small, cus on general purpose workloads, sometimes at the expense simple processor cores allows many cores to be packed onto a of the graphics-specific workloads. Using GPUs for general- single die and into a limited power envelope. purpose computation is a departure from the driving forces be- Although GPUs were originally designed to render images for hind programmable GPUs that were focused on a narrow subset visual displays, today they are used frequently for more general- of graphics rendering operations. Rather than focus on purely purpose applications. However, they must still efficiently per- graphics-related or general-purpose use, we have designed and form what would be considered traditional graphics tasks (i.e. modeled an architecture that optimizes for both simultaneously rendering images onto a screen). GPUs optimized for general- to efficiently handle all GPU workloads. purpose computing may downplay graphics-specific optimiza- In this paper, we present Nyami, a co-optimized GPU archi- tions, even going so far as to offload them to software. -
Operating System Components for an Embedded Linux System
INSTITUTEFORREAL-TIMECOMPUTERSYSTEMS TECHNISCHEUNIVERSITATM¨ UNCHEN¨ PROFESSOR G. F ARBER¨ Operating System Components for an Embedded Linux System Martin Hintermann Studienarbeit ii Operating System Components for an Embedded Linux System Studienarbeit Executed at the Institute for Real-Time Computer Systems Technische Universitat¨ Munchen¨ Prof. Dr.-Ing. Georg Farber¨ Advisor: Prof.Dr.rer.nat.habil. Thomas Braunl¨ Author: Martin Hintermann Kirchberg 34 82069 Hohenschaftlarn¨ Submitted in February 2007 iii Acknowledgements At first, i would like to thank my supervisor Prof. Dr. Thomas Braunl¨ for giving me the opportunity to take part at a really interesting project. Many thanks to Thomas Sommer, my project partner, for his contribution to our good work. I also want to thank also Bernard Blackham for his assistance by email and phone at any time. In my opinion, it was a great cooperation of all persons taking part in this project. Abstract Embedded systems can be found in more and more devices. Linux as a free operating system is also becoming more and more important in embedded applications. Linux even replaces other operating systems in certain areas (e.g. mobile phones). This thesis deals with the employment of Linux in embedded systems. Various architectures of embedded systems are introduced and the characteristics of common operating systems for these devices are reviewed. The architecture of Linux is examined by looking at the particular components such as kernel, standard C libraries and POSIX tools for embedded systems. Furthermore, there is a survey of real-time extensions for the Linux kernel. The thesis also treats software development for embedded Linux ranging from the prerequi- sites for compiling software to the debugging of binaries. -
Anatomy of Cross-Compilation Toolchains
Embedded Linux Conference Europe 2016 Anatomy of cross-compilation toolchains Thomas Petazzoni free electrons [email protected] Artwork and Photography by Jason Freeny free electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 1/1 Thomas Petazzoni I CTO and Embedded Linux engineer at Free Electrons I Embedded Linux specialists. I Development, consulting and training. I http://free-electrons.com I Contributions I Kernel support for the Marvell Armada ARM SoCs from Marvell I Major contributor to Buildroot, an open-source, simple and fast embedded Linux build system I Living in Toulouse, south west of France Drawing from Frank Tizzoni, at Kernel Recipes 2016 free electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 2/1 Disclaimer I I am not a toolchain developer. Not pretending to know everything about toolchains. I Experience gained from building simple toolchains in the context of Buildroot I Purpose of the talk is to give an introduction, not in-depth information. I Focused on simple gcc-based toolchains, and for a number of examples, on ARM specific details. I Will not cover advanced use cases, such as LTO, GRAPHITE optimizations, etc. I Will not cover LLVM free electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 3/1 What is a cross-compiling toolchain? I A set of tools that allows to build source code into binary code for -
Remote-Controlled Ambidextrous Robot Hand Actuated by Pneumatic Muscles: from Feasibility Study to Design and Control Algorithms
Remote-Controlled Ambidextrous Robot Hand Actuated by Pneumatic Muscles: from Feasibility Study to Design and Control Algorithms A thesis submitted for the Degree of Doctor of Philosophy By Emre Akyürek Department of Electronic and Computer Engineering School of Engineering and Design Brunel University June 2015 Declaration of Authorship I, Emre Akyürek, certify that the work introduced in this thesis entitled “Remote- Controlled Ambidextrous Robot Hand Actuated by Pneumatic Muscles: from Feasibility Study to Design and Control” is my own. I confirm that: -This work was entirely achieved while in candidature for a Doctor of Philosophy degree at Brunel University. -The works done by my colleagues or achieved as teamwork are clearly defined and specified. -The articles I have consulted for my research are referenced. Signed: Date: 10/06/2015 i To my ex-brothers in arms Kim-Hwa Khoo, Michaël Rouart and Daniel Truong By the sides of whom I fought these evil monsters called exams and assignments. To those by the sides of whom I bled and suffered, Learning the true meanings of distress and agony. To those who were always at my side To heal my wounds and to repair my weapons, Teaching me the true meanings of friendship and solidarity. To my dear friends Kim-Hwa, Michaël and Daniel, Who were my only family on the battlefield. To my ex-brothers in arms, By the sides of whom I have become the warrior I am. ii Abstract This thesis relates to the development of the Ambidextrous Robot Hand engineered in Brunel University. Assigned to a robotic hand, the ambidextrous feature means that two different behaviours are accessible from a single robot hand, because of its fingers architecture which permits them to bend in both ways. -
Dynamic Task Scheduling and Binding for Many-Core Systems Through Stream Rewriting
Dynamic Task Scheduling and Binding for Many-Core Systems through Stream Rewriting Dissertation zur Erlangung des akademischen Grades Doktor-Ingenieur (Dr.-Ing.) der Fakultät für Informatik und Elektrotechnik der Universität Rostock vorgelegt von Lars Middendorf, geb. am 21.09.1982 in Iserlohn aus Rostock Rostock, 03.12.2014 Gutachter Prof. Dr.-Ing. habil. Christian Haubelt Lehrstuhl "Eingebettete Systeme" Institut für Angewandte Mikroelektronik und Datentechnik Universität Rostock Prof. Dr.-Ing. habil. Heidrun Schumann Lehrstuhl Computergraphik Institut für Informatik Universität Rostock Prof. Dr.-Ing. Michael Hübner Lehrstuhl für Eingebettete Systeme der Informationstechnik Fakultät für Elektrotechnik und Informationstechnik Ruhr-Universität Bochum Datum der Abgabe: 03.12.2014 Datum der Verteidigung: 05.03.2015 Acknowledgements First of all, I would like to thank my supervisor Prof. Dr. Christian Haubelt for his guidance during the years, the scientific assistance to write this thesis, and the chance to research on a very individual topic. In addition, I thank my colleagues for interesting discussions and a pleasant working environment. Finally, I would like to thank my family for supporting and understanding me. Contents 1 INTRODUCTION........................................................................................................................1 1.1 STREAM REWRITING ...................................................................................................................5 1.2 RELATED WORK .........................................................................................................................7 -
An Overview of MIPS Multi-Threading White Paper
Public Imagination Technologies An Overview of MIPS Multi-Threading White Paper Copyright © Imagination Technologies Limited. All Rights Reserved. This document is Public. This publication contains proprietary information which is subject to change without notice and is supplied ‘as is’, without any warranty of any kind. Filename : Overview_of_MIPS_Multi_Threading.docx Version : 1.0.3 Issue Date : 19 Dec 2016 Author : Imagination Technologies 1 Revision 1.0.3 Imagination Technologies Public Contents 1. Motivations for Multi-threading ................................................................................................. 3 2. Performance Gains from Multi-threading ................................................................................. 4 3. Types of Multi-threading ............................................................................................................ 4 3.1. Coarse-Grained MT ............................................................................................................ 4 3.2. Fine-Grained MT ................................................................................................................ 5 3.3. Simultaneous MT ................................................................................................................ 6 4. MIPS Multi-threading .................................................................................................................. 6 5. R6 Definition of MT: Virtual Processors .................................................................................. -
Embedded Linux Size Reduction Techniques
Embedded Linux Conference 2017 Embedded Linux size reduction techniques Michael Opdenacker free electrons [email protected] free electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 1/1 Michael Opdenacker I Michael Opdenacker I Founder and Embedded Linux engineer at free electrons I Embedded Linux expertise I Development, consulting and training I Strong open-source focus I Long time interest in embedded Linux boot time, and one of its prerequisites: small system size. I From Orange, France Penguin from Justin Ternet (https://openclipart.org/detail/182875/pinguin) free electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 2/1 Why reduce size? There are multiple reasons for having a small kernel and system I Run on very small systems (IoT) I Run Linux as a bootloader I Boot faster (for example on FPGAs) I Reduce power consumption Even conceivable to run the whole system in CPU internal RAM or cache (DRAM is power hungry and needs refreshing) I Security: reduce the attack surface I Cloud workloads: optimize instances for size and boot time. I Spare as much RAM as possible for applications and maximizing performance. See https://tiny.wiki.kernel.org/use_cases free electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 3/1 Reasons for this talk I No talk about size since ELCE 2015 I Some projects stalled (Linux tinification, LLVM Linux...) I Opportunity to have a look at solutions I didn’t try: musl library, Toybox, gcc LTO, new gcc versions, compiling with Clang.. -
La Diffusione Del Software Open-Source Nei Sistemi Embedded
Matteo Vellere - La Diffusione del software Open-Source nei Sistemi Embedded Università degli studi di Padova Dipartimento di Tecnica e Gestione dei Sistemi Industriali Corso di Laurea Triennale in Ingegneria Meccanica e Meccatronica LA DIFFUSIONE DEL SOFTWARE OPEN-SOURCE NEI SISTEMI EMBEDDED THE SPREAD OF OPEN-SOURCE SOFTWARE IN EMBEDDED SYSTEMS RELATORE: CH.MO PROF. Reggiani Monica LAUREANDO: Vellere Matteo ANNO ACCADEMICO: 2013/2014 Pag. 1 Matteo Vellere - La Diffusione del software Open-Source nei Sistemi Embedded Pag. 2 Matteo Vellere - La Diffusione del software Open-Source nei Sistemi Embedded INDICE GENERALE INTRODUZIONE.......................................................................................................................4 1.I Sistemi Embedded.................................................................................................................6 1.1.Generalità sui Sistemi Embedded.....................................................................................6 1.2.Evoluzione storica dei dispositivi.....................................................................................8 1.3.Caratteristiche.................................................................................................................10 1.3.1.Microcontrollori e Microprocessori........................................................................10 1.3.2.Field Programmable Gate Array (FPGA)...............................................................11 1.3.3.Digital Signal Processors (DSP).............................................................................11 -
Abkürzungs-Liste ABKLEX
Abkürzungs-Liste ABKLEX (Informatik, Telekommunikation) W. Alex 1. Juli 2021 Karlsruhe Copyright W. Alex, Karlsruhe, 1994 – 2018. Die Liste darf unentgeltlich benutzt und weitergegeben werden. The list may be used or copied free of any charge. Original Point of Distribution: http://www.abklex.de/abklex/ An authorized Czechian version is published on: http://www.sochorek.cz/archiv/slovniky/abklex.htm Author’s Email address: [email protected] 2 Kapitel 1 Abkürzungen Gehen wir von 30 Zeichen aus, aus denen Abkürzungen gebildet werden, und nehmen wir eine größte Länge von 5 Zeichen an, so lassen sich 25.137.930 verschiedene Abkür- zungen bilden (Kombinationen mit Wiederholung und Berücksichtigung der Reihenfol- ge). Es folgt eine Auswahl von rund 16000 Abkürzungen aus den Bereichen Informatik und Telekommunikation. Die Abkürzungen werden hier durchgehend groß geschrieben, Akzente, Bindestriche und dergleichen wurden weggelassen. Einige Abkürzungen sind geschützte Namen; diese sind nicht gekennzeichnet. Die Liste beschreibt nur den Ge- brauch, sie legt nicht eine Definition fest. 100GE 100 GBit/s Ethernet 16CIF 16 times Common Intermediate Format (Picture Format) 16QAM 16-state Quadrature Amplitude Modulation 1GFC 1 Gigabaud Fiber Channel (2, 4, 8, 10, 20GFC) 1GL 1st Generation Language (Maschinencode) 1TBS One True Brace Style (C) 1TR6 (ISDN-Protokoll D-Kanal, national) 247 24/7: 24 hours per day, 7 days per week 2D 2-dimensional 2FA Zwei-Faktor-Authentifizierung 2GL 2nd Generation Language (Assembler) 2L8 Too Late (Slang) 2MS Strukturierte