OS-9® Te c h n i c a l Manual Version 4.2 RadiSys. 118th Street Des Moines, Iowa 50325 515-223-8000 www.radisys.com Revision A • April 2003 Copyright and publication information Reproduction notice This manual reflects version 4.2 Microware OS-9. The software described in this document is intended to Reproduction of this document, in part or whole, by be used on a single computer system. RadiSys Corpo- any means, electrical, mechanical, magnetic, optical, ration expressly prohibits any reproduction of the soft- chemical, manual, or otherwise is prohibited, without written permission from RadiSys Corporation. ware on tape, disk, or any other medium except for backup purposes. Distribution of this software, in part Disclaimer or whole, to any other party or on any other system may constitute copyright infringements and misappropria- The information contained herein is believed to be accurate as of the date of publication. However, tion of trade secrets and confidential processes which RadiSys Corporation will not be liable for any damages are the property of RadiSys Corporation and/or other including indirect or consequential, from use of the parties. Unauthorized distribution of software may OS-9 operating system, Microware-provided software, cause damages far in excess of the value of the copies or reliance on the accuracy of this documentation. involved. The information contained herein is subject to change without notice. April 2003 Copyright ©2003 by RadiSys Corporation. All rights reserved. EPC and RadiSys are registered trademarks of RadiSys Corporation. ASM, Brahma, DAI, DAQ, MultiPro, SAIB, Spirit, and ValuePro are trademarks of RadiSys Corporation. DAVID, MAUI, OS-9, OS-9000, and SoftStax are registered trademarks of RadiSys Corporation. FasTrak, Hawk, and UpLink are trademarks of RadiSys Corporation. † All other trademarks, registered trademarks, service marks, and trade names are the property of their respective owners. Contents Chapter 1: System Overview System Modularity............................................................................................................................... 12. Level 1 -- The Kernel, Clock, and Init Modules............................................................................. 12. Level 2 — IOMAN ....................................................................................................................... 12. Level 3 — File Managers............................................................................................................... 12. Level 4 — Device Drivers .............................................................................................................. 13. Level 5 — Device Descriptors........................................................................................................ 13. I/O Overview....................................................................................................................................... 13. Memory Modules ................................................................................................................................ 14. Basic Module Structure ................................................................................................................. 15. The CRC Value............................................................................................................................. 16. ROMed Memory Modules............................................................................................................16. Module Header Definitions........................................................................................................... 16. mh_com ............................................................................................................................................17 Chapter 2: The Kernel Kernel Functions.................................................................................................................................. 24. System Call Overview .......................................................................................................................... 24. User-State and System-State .......................................................................................................... 24. Installing System-State Routines.................................................................................................... 25. Kernel System Call Processing.............................................................................................................. 26. Non-I/O Calls ............................................................................................................................... 26. I/O Calls........................................................................................................................................ 27. Memory Management ......................................................................................................................... 27. OS-9 Memory Map ............................................................................................................................. 28. System Memory Allocation ........................................................................................................... 28. Operating System Object Code ..................................................................................................... 29. System Global Memory................................................................................................................. 29. System Dynamic Memory ............................................................................................................. 29. User Memory ................................................................................................................................ 29. Memory Fragmentation....................................................................................................................... 30. Colored Memory ................................................................................................................................. 30. Colored Memory Definition List ................................................................................................... 30. SSM and Cache ............................................................................................................................. 33. Cache List............................................................................................................................... 33. PowerPC Processors: SSM and Cache ........................................................................................... 33. Colored Memory in Homogenous Memory Systems ..................................................................... 39. System Performance ...................................................................................................................... 39. Reconfiguring Memory Areas ....................................................................................................... 39. System Initialization............................................................................................................................. 40. Init: The Configuration Module .................................................................................................... 40. Extension Modules .............................................................................................................................. 40. 3 Contents Process Creation .................................................................................................................................. 41. Process Memory Areas .................................................................................................................. 42. Process States ................................................................................................................................ 43. Process Scheduling............................................................................................................................... 44. Preemptive Task Switching............................................................................................................ 44. Chapter 3: Interprocess Communication Signals ................................................................................................................................................. 48. Signal Codes.................................................................................................................................. 48. Signal Implementation................................................................................................................... 49. Non-Recursive Calling............................................................................................................ 50. Recursive Calling .................................................................................................................... 50. Alarms................................................................................................................................................. 52. User-State Alarms.......................................................................................................................... 52. Cyclic Alarms................................................................................................................................ 52. Time of Day Alarms.....................................................................................................................