Au0586 half title page 11/17/05 2:05 PM Page 1 EMBEDDED LINUX SYSTEM DESIGN AND DEVELOPMENT Au0586 title page 11/17/05 2:04 PM Page 1 EMBEDDED LINUX SYSTEM DESIGN AND DEVELOPMENT P. Raghavan • Amol Lad • Sriram Neelakandan Boca Raton New York Published in 2006 by Auerbach Publications Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 © 2006 by Taylor & Francis Group, LLC Auerbach is an imprint of Taylor & Francis Group No claim to original U.S. Government works Printed in the United States of America on acid-free paper 10987654321 International Standard Book Number-10: 0-8493-4058-6 (Hardcover) International Standard Book Number-13: 978-0-8493-4058-1 (Hardcover) Library of Congress Card Number 2005048179 This book contains information obtained from authentic and highly regarded sources. Reprinted material is quoted with permission, and sources are indicated. A wide variety of references are listed. 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Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. Library of Congress Cataloging-in-Publication Data Raghavan, P. (Pichai), 1973- Embedded Linux system design and development / P. Raghavan, Amol Lad, Sriram Neelakandan. p. cm. Includes bibliographical references and index. ISBN 0-8493-4058-6 (alk. paper) 1. Linux. 2. Operating systems (Computers) 3. Embedded computer systems. I. Lad, Amol. II. Neelakandan, Sriram. III. Title. QA76.76.O63R335 2005 005.4'32--dc22 2005048179 Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com Taylor & Francis Group and the Auerbach Publications Web site at is the Academic Division of T&F Informa plc. http://www.auerbach-publications.com All source code in the book is released under GNU GPL v2. It can be used as desired under terms and conditions of GNU GPL v2. Trademarks Ⅲ MIPS is a registered trademark and YAMON is a trademark of MIPS Technologies. Ⅲ IBM and ClearCase are registered trademarks and PowerPC is a trademark of International Business Machines Corporation. Ⅲ UNIX is a registered trademark in the United States and other countries, licensed exclusively through X/Open Company Limited. Ⅲ X11 is a trademark of Massachusetts Institute of Technology. Ⅲ NEC is a registered trademark of NEC Corporation Ⅲ HP is a registered trademark of Hewlett-Packard Company. Ⅲ ColdFire is a registered trademark and Motorola is a trademark of Motorola, Inc Ⅲ Microblaze is trademark of Xilinx Inc Ⅲ Red Hat is a registered trademark and eCos and RedBoot are trademarks of Red Hat, Inc. 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Dedication Raghavan In memory of my late father Amol To Lord Krsna,... my parents, my wife Parul, and my brother Amit Sriram To my family and all Linux enthusiasts vii Contents 1 Intr oduction ............................................................................................. 1 1.1 History of Embedded Linux .................................................... 2 1.1.1 Year 1999 ..................................................................... 3 1.1.2 Year 2000 ..................................................................... 4 1.1.3 Year 2001 ..................................................................... 4 1.1.4 Year 2002 ..................................................................... 5 1.1.5 Year 2003 ..................................................................... 6 1.1.6 Year 2004 ..................................................................... 6 1.2 Why Embedded Linux? ............................................................ 7 1.2.1 Vendor Independence................................................. 7 1.2.2 Time to Market............................................................ 8 1.2.3 Varied Hardware Support ........................................... 8 1.2.4 Low Cost ...................................................................... 8 1.2.5 Open Source................................................................ 9 1.2.6 Standards (POSIX®) Compliance............................. 10 1.3 Embedded Linux Versus Desktop Linux .............................. 10 1.4 Frequently Asked Questions.................................................. 11 1.4.1 Is Linux Too Large?................................................... 11 1.4.2 Is Linux Real-Time Enough?..................................... 11 1.4.3 How Can I Protect My Proprietary Software?......... 12 1.4.4 Should I Buy a Commercial Embedded Linux Distribution?....................................................