Anthony J. Massa

399 Pages·2002·1.79 MB·English

EMBEDDED SOFTWARE
DEVELOPMENT WITH ECOS™
Anthony J. Massa
EMBEDDED SOFTWARE
DEVELOPMENT WITH ECOS
Anthony J. Massa
PRENTICE HALL
PROFESSIONAL TECHNICAL REFERENCE
UPPER SADDLE RIVER, NJ 07458
WWW.PHPTR.COM
WWW.PHPTR.COM/MASSA/
Library of Congress Cataloging-in-Publication Data
Massa, Anthony J.
Embedded software development with eCos / Anthony J. Massa
p. cm.--(Bruce Perens' Open source series)
ISBN 0-13-035473-2
1. Embedded computer systems--Programming. 2. Application
software--Development. 3. Real-time data processing. I. Title. II. Series.
QA76.6 .M364317 2002
005.26--dc21
2002035507
Editorial/production supervision: Techne Group
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This book is dedicated to my girls,
Katie and Deanna.
You mean the world to me.
I love you.

C O N T E N T S
Foreword xv
Preface xvii
Chapter 1 An Introduction to the eCos World 1
1.1 Where It All Started—Cygnus Solutions 1
1.2 The Origins of eCos 2
1.2.1 In a Word: Configurability 3
1.2.2 The eCos Configuration Method 4
1.2.3 eCos Core Components 5
1.2.4 Processor and Evaluation Platform Support 6
1.2.5 eCos Support 6
1.3 Architecture Overview 8
1.3.1 eCos Terminology 8
1.3.1.1 Component Framework 8
1.3.1.2 Component Repository 10
1.3.1.3 Configuration Options 13
1.3.1.4 Components and Packages 14
1.3.1.5 Targets 14
1.3.1.6 Templates 15
1.4 Summary 16
vii
viii Contents
Chapter 2 The Hardware Abstraction Layer 17
2.1 Overview 17
2.1.1 HAL Directory Structure 19
2.1.1.1 Example HAL Function Call Trace 22
2.1.2 HAL Macro Definitions 23
2.1.3 HAL Configuration 24
2.1.3.1 Common Configuration Components 25
2.1.3.2 Architecture-Specific Configuration Components 25
2.1.4 HAL Startup 26
2.2 Summary 29
Chapter 3 Exceptions and Interrupts 31
3.1 Exceptions 31
3.1.1 HAL and Kernel Exception Handling 32
3.1.2 Application Exception Handling 38
3.2 Interrupts 40
3.2.1 eCos Interrupt Model 40
3.2.1.1 Interrupt and Scheduler Synchronization 41
3.2.2 Interrupt Configuration 42
3.2.3 Interrupt Handling 44
3.2.4 Interrupt Control 50
3.2.4.1 Interrupt Service Routine Management 51
3.2.4.2 Interrupt State Management 53
3.2.4.3 Interrupt Controller Management 54
3.3 Summary 58
Chapter 4 Virtual Vectors 59
4.1 Virtual Vectors 59
4.1.1 Virtual Vector Configuration 63
4.1.2 Virtual Vector Table Initialization 64
4.1.2.1 Communication Channels 67
4.2 Summary 71
Chapter 5 The Kernel 73
5.1 The Kernel 73
5.1.1 Kernel Directory Structure 74
5.1.2 Kernel Startup 75
5.1.3 The Scheduler 77
5.1.3.1 Multilevel Queue Scheduler 79
Contents ix
5.1.3.2 Bitmap Scheduler 81
5.1.3.3 Priority Levels 81
5.1.3.4 Scheduler Configuration 83
5.2 Summary 84
Chapter 6 Threads and Synchronization Mechanisms 85
6.1 Threads 85
6.1.1 Thread Stacks and Stack Sizes 94
6.2 Synchronization Mechanisms 95
6.2.1 Mutexes 95
6.2.2 Semaphores 101
6.2.3 Condition Variables 105
6.2.4 Flags 110
6.2.5 Message Boxes 113
6.2.6 Spinlocks 118
6.3 Summary 120
Chapter 7 Other eCos Architecture Components 121
7.1 Counters, Clocks, Alarms, and Timers 121
7.1.1 Counters 125
7.1.2 Clocks 129
7.1.3 Alarms 130
7.1.4 Timers 133
7.2 Asserts and Tracing 134
7.3 ISO C and Math Libraries 138
7.4 I/O Control System 140
7.4.1 I/O Sub-System 142
7.4.2 Device Drivers 146
7.5 Summary 148
Chapter 8 Additional Functionality and Third-Party Contributions 149
8.1 Compatibility Layers 150
8.1.1 POSIX 150
8.1.1.1 EL/IX 151
8.1.2 µITRON 152
8.2 ROM Monitors 152
8.2.1 CygMon 153
8.2.2 RedBoot 153
8.2.3 GDB Stub 154
x Contents
8.3 File Systems 155
8.3.1 ROM File System 157
8.3.2 RAM File System 158
8.3.3 Journalling Flash File System Version 2 160
8.4 PCI Support 160
8.4.1 PCI Library API 161
8.5 USB Support 165
8.6 Networking Support 167
8.6.1 OpenBSD 168
8.6.2 FreeBSD 169
8.6.3 lwIP 170
8.6.4 Networking Threads 170
8.6.5 Networking Configuration 171
8.6.6 Networking Tests 176
8.6.7 DNS Support 178
8.7 SNMP Support 179
8.8 The GoAhead Embedded WebServer 180
8.9 Symmetric Multi-Processing Support 182
8.10 Additional Features 183
8.11 Summary 184
Chapter 9 The RedBoot ROM Monitor 185
9.1 Overview 185
9.2 RedBoot Directory Structure 187
9.3 Installation and Configuration 188
9.3.1 RedBoot Configuration 189
9.3.2 Host Configuration 193
9.3.2.1 Serial 193
9.3.2.2 Ethernet 194
9.4 User Interface and Command Set 195
9.4.1 RedBoot Commands 196
9.4.1.1 Boot Scripting 204
9.5 Summary 206
Chapter 10 The Host Development Platform 207
10.1 Overview 207
10.2 Configuring the Windows Host 209
10.2.1 Installing the Cygwin Native Tools 210
Contents xi
10.2.1.1 Cygwin Tools Directory Structure 217
10.2.1.2 Upgrading the Cygwin Tools 219
10.2.2 Installing the Platform-Specific Cross-Development Tools 220
10.2.3 Installing the eCos Development Kit 223
10.2.3.1 eCos Development Kit Directory Structure 229
10.2.4 Accessing the Online eCos Source Code Repository 229
10.2.4.1 Installing WinCVS 230
10.2.4.2 Setting WinCVS Preferences 235
10.2.4.3 WinCVS Update Commands 236
10.3 Summary 238
Chapter 11 The eCos Toolset 239
11.1 Packages 239
11.1.1 Package Directory Structure 240
11.1.2 The Component Definition Language Overview 243
11.1.2.1 CDL Script Files 243
11.2 The Configuration Tool 248
11.2.1 Screen Layout 248
11.2.1.1 Saving Configurations 251
11.2.1.2 Importing and Exporting Configurations 253
11.2.1.3 Configuration Window 254
11.2.1.4 Conflicts Window 255
11.2.1.5 Properties Window 256
11.2.1.6 Short Description Window 256
11.2.1.7 Output Window 256
11.2.1.8 Memory Layout Window 256
11.2.1.9 Memory Layout Manipulation 257
11.2.2 eCos Repository Database 264
11.2.3 Graphical Representation of CDL Script Files 266
11.2.4 Using Templates 270
11.2.4.1 Conflicts and Resolutions 272
11.2.5 Package Control 274
11.3 Other eCos Tools 274
11.3.1 The Package Administration Tool 275
11.3.2 The Command-Line Configuration Tool 277
11.4 Building the eCos Tools 277
11.5 Additional Open-Source Tools 277
11.5.1 Source-Navigator 278