Advanced RISC Computing Specification Version 1.2 1991, 1992 MIPS Technology Inc.—Printed in the United States of America. 2071 North Shoreline Blvd., Mountain View, California 94039-7311 U.S.A. All rights reserved. This product and related documentation is protected by copyright and distributed under licenses restricting its use, copying, distribution, and decompilation. No part of this product or related documentation may be reproduced in any form by any means without prior written authorization of MIPS and its licensors, if any. RESTRICTED RIGHTS LEGEND: Use, duplication, or disclosure by the United States government is subject to restrictions as set forth in DFARS 252.227-7013 (c)(1)(ii) and FAR 52.227-19. THE COPYRIGHT HOLDER DISCLAIMS ALL WARRANTIES OF MERCHANTABILITY AND FITNESS FOR USE, AND FURTHER DISCLAIMS ANY AND ALL DAMAGES ARISING FROM USE OF THIS SPECIFICATION INCLUDING BUT NOT LIMITED TO DIRECT, INDIRECT, CONSEQUENTIAL AND SPECIAL DAMAGES WHICH MAY ARISE FROM ANY USE OF THIS SPECIFICATION. THE USER OF THIS SPECIFICATION HEREBY AGREES TO HOLD THE COPYRIGHT HOLDER, ITS AGENTS, PREDECESSORS, ASSIGNS, AND SUCCESSORS HARMLESS FROM ANY DAMAGES, HOWEVER DENOMINATED, WHICH MAY ARISE FROM ITS USE OF THIS SPECIFICATION. THE TECHNICAL MATERIALS IN THIS SPECIFICATION MAY BE COVERED BY ONE OR MORE PATENTS. ACCESS TO THIS SPECIFICATION DOES NOT DIRECTLY, INDIRECTLY, OR BY IMPLICATION LICENSE ANY PATENTS WHICH COVER THE MATERIALS SET FORTH HEREIN. POSSESSION OF THIS SPECIFICATION DOES NOT AUTHORIZE USE OF THIS SPECIFICATION. THIS SPECIFICATION IS SUBJECT TO CHANGE WITHOUT NOTICE. NO REPRESENTATIONS, EXPRESS OR IMPLIED, BY IMPLICATION, ESTOPPEL OR OTHERWISE RESTRICT THE RIGHT TO CHANGE OR REVISE THIS SPECIFICATION. USER’S USE OF ANY PORTION OF THIS SPECIFICATION SHALL BE DEEMED TO BE AN ACCEPTANCE OF THE ABOVE DISCLAIMERS AND CONDITIONS OF USE. TRADEMARKS All other product names mentioned herein are the trademarks of their respective owners. 2 Table of Contents Preface ..........................................................................................................................11 1. Introduction to the ARC Specification ................................................................14 1.1 Covered By the ARC Specification..................................................................15 1.2 Covered By Addenda To The ARC Specification............................................16 1.3 Not Specified by the ARC Specification ..........................................................16 1.4 Conventions Used In the ARC Specification....................................................16 1.5 Conformance ....................................................................................................17 Part 1: Base Specification 2. System Architecture ..............................................................................................19 2.1 Architectural Working Statement .....................................................................19 2.2 System States....................................................................................................20 2.2.1 State Diagram............................................................................................20 2.3 Software Subsystems........................................................................................22 2.3.1 Application Software.................................................................................23 2.3.2 Operating System Software .......................................................................23 2.3.3 Hardware Abstraction Layer (HAL) Software .........................................23 2.3.4 Device Drivers ..........................................................................................24 2.3.5 Loader, Installer, and Independent Utility Software..................................24 2.4 Hardware Subsystems.......................................................................................25 2.4.1 Processing Subsystems..............................................................................25 2.4.2 Peripheral Attachment Subsystems ...........................................................25 2.5 Firmware ..........................................................................................................26 2.6 System Interface Definitions ............................................................................26 3 Contents 3. Platform Hardware ...............................................................................................27 3.1 System Configurations......................................................................................27 3.2 Server System Configuration............................................................................28 Consequences of Non-Compliance...................................................................29 3.2.1 Processor Unit...........................................................................................30 3.2.2 Floating Point Unit....................................................................................31 3.2.3 Cache.........................................................................................................31 3.2.4 Memory.....................................................................................................31 3.2.5 Timing Function Support ..........................................................................31 3.2.6 Real Time Clock........................................................................................32 3.2.7 System Timer ............................................................................................32 3.2.8 Console......................................................................................................32 3.2.9 CD-ROM...................................................................................................32 3.3 Desktop System Configuration.........................................................................32 3.3.1 Keyboard...................................................................................................32 Requirements....................................................................................................33 3.3.2 Pointing Device.........................................................................................33 Requirements....................................................................................................33 3.3.3 Video Subsystem.......................................................................................34 Requirements....................................................................................................34 3.3.4 Audio.........................................................................................................35 3.4 Optional Hardware ...........................................................................................37 3.4.1 Floppy Drive .............................................................................................37 3.4.2 Serial Ports ................................................................................................37 3.4.3 Parallel Port...............................................................................................38 3.4.4 SCSI Interface ...........................................................................................39 3.4.5 Network Interface......................................................................................40 Ethernet ............................................................................................................40 Token Ring.......................................................................................................40 3.5 Additional Hardware ........................................................................................41 3.6 Media Formats..................................................................................................41 3.6.1 Media Formats for System Load ...............................................................42 3.6.2 System Partition Formats ..........................................................................42 3.6.3 Diskettes (5 1/4-inch and 3 1/2 inch) ........................................................42 3.6.4 CD-ROM...................................................................................................43 3.6.5 Disk Storage Devices ................................................................................43 3.6.6 Network.....................................................................................................43 3.6.7 Data Interchange .......................................................................................44 3.7 Processing Subsystem.......................................................................................44 3.7.1 Related Consequences...............................................................................45 3.8 Peripheral Attachment Subsystems (I/O Bus) ..................................................46 3.8.1 Requirements.............................................................................................46 3.8.2 Related Consequences...............................................................................46 4 Contents 4. Platform Firmware................................................................................................47 4.1 Firmware Conventions......................................................................................47 4.1.1 Calling Procedures ....................................................................................47