Amiga Linux/m68k Loader <author>Geert Uytterhoeven <date>Version 1.0, 7 September 1996 <abstract> This document describes the usage of the Amiga Linux/m68k Loader </abstract>  <toc>  <sect>Introduction The Amiga Linux/m68k Loader (short: <em/Lilo/) allows you to load Linux/m68k from a disk boot block. You can choose among multiple kernel images --- without having to transport those kernels from a Linux/m68k partition to an <em/AmigaOS/ partition --- and can boot even <em/AmigaOS/ itself. This greatly eases the boot process for normal users and provides a development boost for kernel hackers. <sect1>Features <itemize> <item>Can boot Linux/m68k and <em/AmigaOS/. <item>Supports multiple kernel images. <item>Supports both <em/ELF/ and <em/a.out/ (<em/QMAGIC/ and <em/ZMAGIC/) kernels. <item>Supports multiple command lines. <item>Supports the standard <em/Amiga/ console and an <em/ANSI/ terminal connected to the builtin serial port. <item>Supports automatic and interactive booting, with an optional timeout. <item>Supports ramdisk images. <item>Boot code can be installed on <em/AmigaOS/ and Linux/m68k partitions. <item>Password protection on a per kernel base. <item>Boot monitor with a separate password. <item>Can backup and restore boot blocks. </itemize> <sect1>System requirements <itemize> <item>An <em/Amiga/ that can run Linux/m68k. <item>A working installation of Linux/m68k 2.0.x. <item><em/Kickstart V36/ or higher. <item><em/HdToolBox/. </itemize> <sect1>Why <em/Lilo/ for <em/Amiga/? I decided to write a version of <em/Lilo/ for the <em/Amiga/ because I was tired of putting Linux/m68k kernels on a floppy and read them back with the <em/FLAT-handler/ to test them. At that time this was the only decent way to transport files from a Linux/m68k partition to an <em/AmigaOS/ partition, since you can't access files on an <em/ext2fs/ partition under <em/AmigaOS/ (However, this is going to change. For more information, take a look at <url url="http://theory.cs.bonn.edu/~fasten/" name="Ext2fs for AmigaOS">.). Now we have <em/Ethernet/ support file transport became much easier --- I usually <em/FTP/ my files to a <em/Sun SPARCstation 1/ or Linux/i386 box, and get them back through AmiTCP/IP ---, but it's still a real hassle just to test a new kernel. And what with people who want to wipe <em/AmigaOS/ completely off of their hard disk? But here is <em/Lilo/! The support for a terminal connected to the builtin serial port was added when my <em/A1960/ monitor died (again) and I desperately needed such a feature.  <sect>Installing <em/Lilo/ <bf/Important notes:/ <itemize> <item>To perform the actions described below, you must be <em/root/ on your Linux/m68k system, unless noted otherwise. <item>Some of these actions might be dangerous for the integrity of your system. Always think twice, ... then think again, and <bf/use this at your own risk!/ </itemize> First you need to choose a partition to install the <em/Lilo/ boot block on. This can be any Linux/m68k partition or <em/bootable AmigaOS/ partition. If you want to use <em/Lilo/ to boot <em/AmigaOS/ too, you must install the <em/Lilo/ boot block on the <em/AmigaOS/ partition you want to boot from. This boot partition is represented by a block special device file (created with <em/mknod/), which is usually located in the <tt>/dev</tt> directory. By convention block special device files for <em/SCSI/ drives are represented by entries of the kind <tt>/dev/sd*</tt>, while <em/IDE/ drives are associated with the <tt>/dev/hd*</tt> entries. I have e.g. 2 <em/IDE/ drives in my A4000/040: a <em/Conner CP30544/ (master) of 540 MB and the original <em/Seagate ST3144A/ (slave) of 130 MB (This changed due to my (Linux/m68k's? <em/X11R6.1/'s?) hunger for diskspace, but I left the original example for the sake of simplicity.). The <em/Conner/ has six partitions, while the <em/Seagate/ has only one partition. So I have the following block special device files:  <verb> Unit - Unit & Block special device file - File system - Usage </verb>  Since I wanted to use <em/Lilo/ to boot both <em/AmigaOS/ (from <tt>/dev/hda1</tt>) and Linux/m68k (from <tt>/dev/hda3</tt>), I had to install <em/Lilo/ on <tt>/dev/hda1</tt>. <sect1>Installing the <em/Lilo/ boot block Now edit the file <tt>/etc/lilo.conf</tt>. Refer to Section <ref id="sec:conf" name="<tt>/etc/lilo.conf</tt>"> for the configuration file syntax. Then install the <em/Lilo/ boot block with the following command line: <tscreen> <tt/lilo [--force]/ </tscreen> with <descrip> <tag/<tt>--force</tt>/ To prevent data loss in case of a mistake, <em/Lilo/ will never overwrite an unknown boot block, unless you use this force option. </descrip> If there exists no backup of the boot block yet --- i.e. if you're installing <em/Lilo/ for the first time --- it will automatically create a backup of the old boot block in the file <tt>/boot/backup.xx.yy</tt> with <tt/xx/ and <tt/yy/ the major and minor numbers of the device you installed the boot block on. This will allow you to uninstall <em/Lilo/ completely or to recover from mistakes. In most cases you can just enter <tscreen> <tt/lilo/ </tscreen> or <tscreen> <tt/lilo --force/ </tscreen> if you're installing a <em/Lilo/ boot block on a partition with an <em/ext2fs/ or <em/minix/ file system for the first time because those partitions don't have a known boot block at that moment. <bf>Warning: Every time you change or move any kernel image or config file you <em/must/ rerun <tt/lilo/</bf>! Just enter <tscreen> <tt/lilo/ </tscreen> to update all important data. <sect1>Updating the <em/Rigid Disk Block/ If this is the first time you install <em/Lilo/ you need to use <em/HdToolBox/ (under <em/AmigaOS/) to update the <em/Rigid Disk Block/ of the device your boot partition is located on. Make sure to remember the original values of all options you change, in case you might want to uninstall <em/Lilo/! Start <em/HdToolBox/ and perform the following actions (This list reflects the <em/AmigaOS/ 3.1 version of <em/HdToolBox/. Other versions are slightly different.): <itemize> <item>Select the corresponding device for your boot partition and click on <tt/Partition Drive/ to get the <tt/Partitioning/ menu. <item>Choose the partition and enable <tt/Advanced Options/. <item>If the partition isn't already bootable, make it bootable by enabling <tt/Bootable/. You may want to change the <tt/Boot Priority/ too. <item>Click on <tt/Change.../ to get the <tt/File System Characteristics/ menu. <item>If you did <em/not/ install the <em/Lilo/ boot block on an <em/AmigaOS/ partition: <itemize> <item>Set <tt/File System/ to <tt/Custom File System/. <item>Fill in an appropriate value after <tt/Identifier =/. I suggest <tt/0x45585432/ (<tt/EXT2/ in <em/HEX ASCII/) for a partition with <em/ext2fs/ and <tt/0x4D494E49/ (<tt/MINI/ in <em/HEX ASCII/) for a partition with the <em/minix/ file system. Alternatively you could use <tt/0x554E4901/ (<tt/UNI\01/ (This value was originally reserved for a <em/UNIX/ boot file system, i.e. for the boot partition of <em/Amiga UNIX System V Release 4/, also known as <em/AMIX/.) in <em/HEX ASCII/) if you do not intend to access the partition under <em/AmigaOS/. <item>Don't worry about the warning you will get later that tells you the data on the partition will be lost. <em/HdToolBox/ doesn't know that <em/ext2fs/ and the <em/minix/ file system don't use the <tt/File System/ field in the <em/Rigid Disk Block/. </itemize> <item>Enable <tt/Use custom boot code/ and set <tt/Number of custom boot blocks/ to <tt/2/. This value assumes the <tt/File system block size/ is set to it's default value of <tt/512/. <em/Never/ enable this for an <em/AmigaOS/ partition that contains the <em/original AmigaOS/ boot block, since this is definitely not bootable!. <item>Click on <tt/OK/, on <tt/OK/ and on <tt/Save Changes to Drive/. </itemize> If you installed the <em/Lilo/ boot block on another partition than the previous time, you also need to use <em/HdToolBox/ to update your <em/Rigid Disk Block/. <sect1>Uninstalling <em/Lilo/ To uninstall a <em/Lilo/ boot block, just restore the <em/Rigid Disk Block/ options for that partition to their original values (using <em/HdToolBox/), and use the <tt/--uninstall/ option of <em/Lilo/: <tscreen> <tt/lilo --uninstall/ </tscreen> This will automatically restore the boot block that was backed up during the first time installation.  <sect>Files used by <em/Lilo/ <sect1><tt>/boot/loader</tt> This is a template for an <em/AmigaOS/ executable that displays the boot menu and loads the desired operating system on booting. <sect1><tt>/boot/loader.patched</tt> This is the actual raw PC-relative executable that displays the boot menu and loads the desired operating system on booting. It is created by <em/Lilo/ by patching <tt>/boot/loader</tt> and by adding a PC-relative header that decodes the <em/AmigaOS/ executable file format. <sect1><tt>/boot/map</tt> This file contains all configuration options and all necessary information to find all files, as defined by <tt>/etc/lilo.conf</tt>. It is created by <em/Lilo/. For more information about the used file format, see section <ref id="sec:tags" name="The tagged map file format">. <sect1><tt>/boot/backup.xx.yy</tt> This file contains a backup of the original boot block on the device with major number <tt/xx/ and minor number <tt/yy/. It's created by <em/Lilo/ if you install a boot block on the corresponding device and no backup exists yet. <sect1><tt>/sbin/lilo</tt> This is the Linux/m68k executable that installs <em/Lilo/. <sect1><tt>/etc/lilo.conf</tt><label id="sec:conf"> This is the <em/Lilo/ configuration file, an <em/ASCII/ file which defines the boot configuration for <em/Lilo/. It contains a header with global options, one or more boot records, and zero or more file definitions. The character <tt/#/ indicates that the rest of the line is a comment and thus to be ignored. All numbers in this file can be entered in decimal (e.g. <tt/53270/), hexadecimal (e.g. <tt/0xD016/) or octal (e.g. <tt/0150026/) form. <sect2>Header The header looks like <tscreen><verb> header options ... endheader </verb></tscreen> Valid header options are: <descrip> <tag/<tt>bootdev "</tt>name<tt/"</tt>/ Specify the block special device to install the boot block on (e.g. <tt>/dev/hda1</tt>). <tag/<tt>altdev "</tt>device<tt>"</tt> unit/ Specify the <em/AmigaOS/ name and unit number for an alternate boot device (e.g. <tt/scsi.device/ and <tt/0/). In most cases you don't need this option, but if the device that contains your kernel images and the files <tt>/boot/loader.patched</tt> and <tt>/boot/map</tt> is different from the device you want to install the boot block on (specified with the <tt/bootdev/ option), you need to specify the <em/AmigaOS/ device name and unit number that corresponds with the device those files reside on. <tag/<tt>default "</tt>label<tt/"</tt>/ Specify that the boot record with label <em/label/ is the default boot operating system. Default is the first boot record. <tag/<tt>auto</tt> flag/ If <em/flag/ is <tt/true/, <em/Lilo/ will automatically boot the default operating system, unless you hold a qualifier (<tt/ALT/, <tt/AMIGA/, <tt/CTRL/, <tt/SHIFT/, <tt/CAPS LOCK/ or one of the mouse-buttons) or press a key on the auxiliary console during booting. If <em/flag/ is <tt/false/, a boot prompt will always appear. So use <tt/true/ if you think `Why do I need a boot menu? I already have one in ROM!'. Default is <tt/false/. <tag/<tt>timeout</tt> number/ Specify the number of seconds to wait at the boot prompt before the default operating system is chosen automatically. Use <tt/0/ for an infinite timeout value. Default is <tt/20/. <tag/<tt>aux</tt> flag/ If <em/flag/ is <tt/true/, the loader will not only use the standard console, but also the auxiliary console (a terminal on the builtin serial port). Default is <tt/false/. <tag/<tt>baud</tt> number/ Specify the speed (in bps --- bits per second) for the auxiliary console (if enabled). Default is <tt/9600/ (<em/ROM/ default). <tag/<tt>password "</tt>name<tt>"</tt>/ Specify the master password. This password will be asked for if you want to enter the boot monitor on booting. Default is an empty string. <tag/<tt>debug</tt> flag/ If <em/flag/ is <tt/true/ the loader will enter debug mode and display additional information during startup. Default is <tt/false/. <tag/<tt>prompt "</tt>text<tt/"</tt>/ Specify the loader prompt. The following character sequences are interpreted specially: <descrip> <tag/<tt>\b</tt>/ <em/Backspace/ <tag/<tt>\e</tt>/ <em/Escape/ <tag/<tt>\n</tt>/ <em/Line Feed/ <tag/<tt>\r</tt>/ <em/Carriage Return/ <tag/<tt>\t</tt>/ <em/Tab/ <tag/<tt>\\</tt>/ <tt/$\backslash$/ </descrip> The default prompt is `<tt/Boot image: /'. <tag/<tt>kickrange</tt> min max/ If the current <em/Kickstart/ version lies outside the range <em/min/--<em/max/, <em/Lilo/ will always boot <em/AmigaOS/ in case of a non-interactive boot. Use this if you have strange hardware that doesn't allow you to boot Linux/m68k from the `wrong' <em/Kickstart/ version. The default range is 0--65535, so all <em/Kickstart/ versions will be accepted. </descrip> <sect2>Boot records The boot records define one or more {operating system/s you can select at boot time. Make sure all your kernel images and the files <tt>/boot/map</tt>, <tt>/boot/loader.patched</tt> are located on the same physical device. A boot record is defined by <tscreen><verb> bootrec "label" options ... endrec/ </verb></tscreen> with <em/label/ the label of the boot record. Valid boot record options are: <descrip> <tag/<tt>alias "</tt>label<tt>"</tt>/ Specify an alias name for this boot record. <tag/<tt>type "</tt>name<tt>"</tt>/ Specify the operating system type for this boot record. Valid types are: <descrip> <tag/<tt>linux</tt>/ Linux/m68k. This is the default. <tag/<tt>amiga</tt>/ <em/AmigaOS/. This only works if you install the <em/Lilo/ boot block on a valid <em/AmigaOS/ boot partition. <tag/<tt>netbsd</tt>/ <em/NetBSD-Amiga/. This doesn't work yet~:-) </descrip> <tag/<tt>image "</tt>name<tt>"</tt>/ Specify the full qualified file name of the kernel image for this boot record. This file needs not to exist (except for the default boot record) --- this is useful for testing purposes ---, but if it exists, it must be located on the <tt/bootdev/ device, or on the <tt/altdev/ device, if the <tt/altdev/ option is specified. This option must not be used if <tt/type/ is set to <tt/amiga/. <tag/<tt>args "</tt>name<tt>"</tt>/ Specify the kernel command line for this boot record. This option must not be used if <tt/type/ is set to <tt/amiga/. Default is an empty string. <tag/<tt>password "</tt>name<tt>"</tt>/ If this option is defined, <em/name/ is the password for this boot record. It must be supplied if you want to boot from this record. Default is no password. <tag/<tt>chipram</tt> size/ Override the detected <em/Chip RAM/ size and set it to <em/number/ bytes. <tag/<tt>fastram</tt> address size/ Override the detected adresses and sizes of <em/Fast RAM/ chunks. Each entry defines a <em/Fast RAM/ chunk at adress <em/address/ containing <em/size/ bytes, thus you can specify multiple <em/Fast RAM/ chunks. <tag/<tt>model</tt> type/ Override the detected <em/Amiga/ model. <em/type/ can be any of <itemize> <item><tt/A500/ <item><tt/A500+/ <item><tt/A600/ <item><tt/A1000/ <item><tt/A1200/ <item><tt/A2000/ <item><tt/A2500/ <item><item><tt/A3000/ <item><tt/A3000T/ <item><tt/A3000+/ <item><item><tt/A4000/ <item><tt/A4000T/ <item><tt/CDTV/ <item><tt/CD32/ <item><tt/Draco/ </itemize> or a number corresponding to one of the model definitions in <tt><asm/amigatypes.h></tt>. <tag/<tt>ramdisk "</tt>name<tt>"</tt>/ Specify the full qualified file name of a file containing a file system to be used a a ramdisk. This file needs not to exist but if it exists, it must be located on the <tt/bootdev/ device, or on the <tt/altdev/ device, if the <tt/altdev/ option is specified. This option must not be used if <tt/type/ is set to <tt/amiga/. Default is an empty string. </descrip> <sect2>File definitions The file definitions allow you to specify some addional files to be added to the map file. These files can then be referenced from withing the boot monitor. Make sure all these files are located on the same physical device as the kernel images. A file definition looks like <tscreen> <tt/file "/<em/name/<tt/"/ </tscreen> with <em/name/ the full qualified file name of the file. <sect2>Sample configuration file This example assumes: <itemize> <item><tt>/dev/hda1</tt> is your main <em/AmigaOS/ partition, <item><tt>/dev/hdb1</tt> is your main Linux/m68k partition, <item><tt>/boot/*</tt>, <tt>/vmlinux</tt> and <tt>/usr/src/linux/vmlinux</tt> reside on <tt>/dev/hdb?</tt>, <item><tt>/dev/hdb</tt> under Linux/m68k is equivalent to <tt/scsi.device/ unit <tt/1/ under <em/AmigaOS/. </itemize> Note that in this case the <tt/altdev/ option is used because <tt>/dev/hda</tt> and <tt>/dev/hdb</tt> are two different physical devices. <tscreen><verb> # # Amiga Linux/m68k Loader # # Sample Configuration File # header bootdev "/dev/hda1" altdev "scsi.device" 1 default "linux" auto false timeout 20 aux false baud 9600 password "amiga" debug false endheader bootrec "amiga" type amiga endrec bootrec "linux" type linux image "/vmlinux" args "ro root=/dev/hdb1" endrec bootrec "single" image "/vmlinux"; args "ro single root=/dev/hdb1" password "single" endrec bootrec "test1" image "/usr/src/linux/vmlinux" endrec bootrec "test2" image "/usr/src/linux/vmlinux" args "ro root=/dev/hdb1" endrec </verb></tscreen>  <sect>Command line options <tt>/sbin/lilo</tt> is used to install a Linux/m68k boot block loader on a boot partition. It can also be used to save boot blocks to a file or restore boot blocks from a file. <tscreen> <tt/lilo/ <tt/[/<em/options .../<tt/]/ </tscreen> Valid options are: <descrip> <tag/<tt>--help</tt>/ Display the usage information. <tag/<tt>--verbose</tt>/ Enable verbose mode. <tag/<tt>--force</tt>/ Force installation on a partition with an unknown boot block. <tag/<tt>--backup</tt>/ Force a boot block backup on installation, even if a backup already exists. <tag/<tt>--uninstall</tt>/ Uninstall <em/Lilo/ by restoring the backed up boot block. <tag/<tt>--root</tt> prefix/ Specify the prefix to be used for all path names. This is useful when creating boot floppies, or for debugging. <tag/<tt>--restore-from</tt> file/ Restore the boot block from <em/file/. <tag/<tt>--save-to</tt> file/ Save the boot block to <em/file/ first. <tag/<tt>--device</tt> device/ Override the block special device that's specified in <tt>/etc/lilo.conf</tt>. <tag/<tt>--dostype</tt> id/ Specify the <em/DosType/ for the boot block. Valid <em/DosTypes/ are: <descrip> <tag/<tt>BOOU</tt>/ Generic boot disk <tag/<tt>DOS0</tt>/ <em/OFS/ disk <tag/<tt>DOS1</tt>/ <em/FFS/ disk <tag/<tt>DOS2</tt>/ <em/OFS INTL/ disk <tag/<tt>DOS3</tt>/ <em/FFS INTL/ disk <tag/<tt>DOS4</tt>/ <em/OFS DC/ disk <tag/<tt>DOS5</tt>/ <em/FFS DC/ disk <tag/<tt>muFS</tt>/ <em/MultiUser FFS INTL/ disk <tag/<tt>muF0</tt>/ <em/MultiUser OFS/ disk <tag/<tt>muF1</tt>/ <em/MultiUser FFS/ disk <tag/<tt>muF2</tt>/ <em/MultiUser OFS INTL/ disk <tag/<tt>muF3</tt>/ <em/MultiUser FFS INTL/ disk <tag/<tt>muF4</tt>/ <em/MultiUser OFS DC/ disk <tag/<tt>muF5</tt>/ <em/MultiUser FFS DC/ disk </descrip> Default is the original <em/DosType/ of the partition, or <tt/BOOU/ for partitions with an unknown boot block (if <tt/--force/ is specified too). <tag/<tt>--checksum</tt>/ Fix the boot block checksum. <tag/<tt>--version</tt>/ Display the version information. </descrip> All options also have a short form: <descrip> <tag/<tt>-h</tt>/ <tt/--help/ <tag/<tt>-v</tt>/ <tt/--verbose/ <tag/<tt>-f</tt>/ <tt/--force/ <tag/<tt>-b</tt>/ <tt/--backup/ <tag/<tt>-u</tt>/ <tt/--uninstall/ <tag/<tt>-w</tt>/ <tt/--root/ <tag/<tt>-r</tt>/ <tt/--restore-from/ <tag/<tt>-s</tt>/ <tt/--save-to/ <tag/<tt>-d</tt>/ <tt/--device/ <tag/<tt>-t</tt>/ <tt/--dostype/ <tag/<tt>-c</tt>/ <tt/--checksum/ <tag/<tt>-V</tt>/ <tt/--version/ </descrip> Note: people who understand Dutch or German will probably easily remember that <tt/-w/ is short for <tt/--root/.  <sect>The <em/Lilo/ boot prompt If <em/Lilo/ is configured not to boot automatically, or if you do one of the following things during boot time: <itemize> <item>hold <tt/ALT/, <tt/AMIGA/, <tt/CTRL/, <tt/SHIFT/ or <tt/CAPS LOCK/, <item>hold one of the mouse-buttons, <item>press a key on the terminal connected to the builtin serial port if the auxiliary console is enabled, </itemize> a boot prompt will appear on the <em/Amiga/ console and, if enabled, on the terminal too. <sect1>Normal user prompt You can perform the following actions: <itemize> <item>Hit <tt/ENTER/ to boot the default operating system. <item>Enter <tt/?/ or <tt/help/, or press <tt/TAB/ to get a list of valid commands and boot record labels. <item>Enter the label of a boot record to boot the corresponding operating system. If this record has a password attached to it, the loader will prompt for it first and will boot from this record only if you enter the correct password. <item>Enter <tt/su/ to enter the boot monitor. The loader will prompt for the master password first and will enter the boot monitor only if you enter the correct password. <item>Sit and wait: after the specified timeout the loader will boot the default operating system automatically. </itemize> <sect1>The boot monitor Once you're in the boot monitor, the timeout is disabled and you have advanced control over the booting process. You can enter one of the following commands: <descrip> <tag/<tt>help</tt> or <tt>?</tt>/ Display usage information. <tag/<tt>version</tt>/ Display version information. <tag/<tt>list records</tt> or <tt>list files</tt>/ List all available boot records and/or files. <tag/<tt>boot</tt> label/ Boot from boot record <em/label/. If <em/label/ is omitted, the current boot settings are used. <tag/<tt>use</tt> label/ Copy the boot record <em/label/ to the current boot settings. If <em/label/ is omitted, the default boot record is assumed. <tag/<tt>info</tt> label/ Get information about the boot record <em/label/. If <em/label/ is omitted, information about the current boot settings is dumped. <tag/<tt>set</tt> var values .../ Change a variable for the current boot settings. If <em/var/ is omitted, this command is equivalent to <tt/list/. If no values are specified, the behavior depends on the variable but tries to be intuitive. The following variables can be changed: <descrip> <tag/<tt>type</tt>/ The operating system type. <tag/<tt>kernel</tt>/ The full qualified file name of the kernel image. This file <em/must/ be available. Use the <tt/file/ option in the configuration file to add your own files. <tag/<tt>ramdisk</tt>/ The full qualified file name of the ramdisk image. This file <em/must/ be available. Use the <tt/file/ option in the configuration file to add your own files. <tag/<tt>args</tt>/ The kernel command line. <tag/<tt>debug</tt>/ The debug flag: <tt/true/ or <tt/false/. <tag/<tt>model</tt>/ The <em/Amiga/ model. Default is <tt/auto/, i.e. autodetect. <tag/<tt>chip</tt>/ The amount of <em/Chip RAM/. Default is <tt/auto/, i.e. autodetect. <tag/<tt>nummem</tt>/ The number of <em/Fast RAM/ chunks. Default is <tt/auto/, i.e. autodetect. <tag/<tt>mem</tt>/ The address and size of a <em/Fast RAM/ chunk. The value syntax is <em/number address size/, with <em/number/ the number (1--<tt/nummem/) of the memory chunk. </descrip> </descrip> Commands are case insensitive, and can be abbreviated.  <sect>Miscellaneous <sect1>Implicit kernel command line options <em/Lilo/ automatically adds the following options to the kernel command line: <descrip> <tag/<tt>BOOT_IMAGE=</tt>label/ <em/label/ is the label of the boot record that's used for booting. <tag/<tt>auto</tt>/ This is added only in case of an automatic boot, i.e. in one of the following cases: <itemize> <item>No boot prompt appeared. <item>You choose the default operating system by just hitting <tt/ENTER/. <item>The timeout was reached. </itemize> </descrip> Of course you can override this when you're in the boot monitor. <sect1>Keeping <em/Lilo/ up-to-date <em/Lilo/ now uses the same bootstrap code as <em/Amiboot/ to ease code maintenance. This also means that all you have to do to keep pace with the newest bootstrap code is to recompile <em/Lilo/ on every <em/Amiboot/ update. <sect1>Creating boot floppies If you want to create a boot floppy with a <em/Lilo/ boot block, use the <tt/--root/ option to tell <em/Lilo/ to use the file system on the floppy instead of your normal root file system, e.g. <tscreen> <tt/lilo --root /floppy/ </tscreen> assuming you have mounted the floppy file system on <tt>/floppy</tt>. After running <em/Lilo/, you may want to remove the following files from the floppy file system to recover valuable space: <itemize> <item><tt>boot/loader</tt> <item><tt>boot/backup.*</tt> <item><tt>etc/lilo.conf</tt> </itemize> <em/Lilo/ only needs <tt>/boot/loader.patched</tt> and <tt>/boot/map</tt> (and a kernel image, of course) to boot.  <sect>Theory of operation If you're not familiar with the internals of the <em/Amiga/ boot process, you may want to read Appendix <ref id="apx:booting" name="The Amiga boot process"> first. <sect1>Program flow If you install a special <em/Lilo/ boot block on a device, <em/Lilo/ performs the following actions: <itemize> <item>First it reads and parses the configuration file <tt>/etc/lilo.conf</tt>. <item>Since <em/AmigaOS/ can't access files on an <em/ext2fs/ or <em/minix/ file system natively, it should know where the data blocks of the files are stored. Thus for every kernel image you may want to boot from, <em/Lilo/ looks up the data blocks of the images, using the <tt/FIBMAP/ <em/ioctl()/ and stores them in the file <tt>/boot/map</tt>, together with the configuration options. <item>Then <em/Lilo/ reads the loader template executable <tt>/boot/loader</tt>, looks up where <tt>/boot/map</tt> is stored on the disk, patches the loader template executable so it knows where to find the data blocks of <tt>/boot/map</tt>, adds a PC-relative header that decodes the <em/AmigaOS/ executable file format and stores the result in <tt>/boot/loader.patched</tt>. <item>During the last step <em/Lilo/ looks up the data blocks for <tt>/boot/loader.patched</tt>, fills them in in the boot code and writes the boot code to the boot block of the device specified in <tt>/etc/lilo.conf</tt>. </itemize> If the <em/Amiga/ tries to boot from a partition you installed <em/Lilo/ on, the system loads the special boot code and executes it. The boot code loads the raw PC-relative executable <tt>/boot/loader.patched</tt> and executes it. Afterwards <tt>/boot/loader.patched</tt> reads <tt>/boot/map</tt>, eventually asks the user for a boot operating system, and loads the desired operating system. <sect1>The boot block code The system calls the boot block code and passes it the <em/BootRequest/ (of type <tt/struct IOStdReq/) for the boot device. At that moment the system has not been initialized completely, e.g. <em/dos.library/ is still missing. This has the following consequences: <itemize> <item>We can't use files, so we need to use raw device I/O. Besides, <em/AmigaOS/ doesn't know <em/ext2fs/ or the <em/minix/ file system either. As an alternative a file is represented by an array of <tt/u_long/s (a <em/vector/). The first <tt/u_long/ in this array contains the length of the file (in bytes); the following <tt/u_long/s are disk offsets for the data blocks, with holes (A hole is a place in a file where a whole block contains nothing but zeroes. Linux/m68k doesn't store such a block on disk explicitly, but marks it specially, to save diskspace.) indicated by a disk offset of 0. The data block size is 1024 bytes (This is the default block size for Linux/m68k. <em/AmigaOS/ however uses a default block size of 512 bytes.). The data blocks can be read by using the <em/BootRequest/, or by opening the alternate boot device if the <tt/altev/ option was used in <tt>/etc/lilo.conf</tt>. <item>We can't use <em/DOS/ devices like <em/CON:/. Thus the loader opens a window and uses the <em/console.device/ for communication with the user. <item>The <em/serial.device/ resides on disk, so raw serial I/O (using the private <em/exec.library/ functions <em/RawMayGetChar()/ and <em/RawPutChar()/) is used instead to support the auxiliary console. </itemize> The boot block code loads and calls the loader. The loader should return <tt/FALSE/ in case of an error, and <tt/TRUE/ if the user wants to boot <em/AmigaOS/; in all other cases it shouldn't return. <sect1>The boot library The boot block code exports some functions for file access and execution by passing a function table pointer to the loader. <sect2>File access functions These functions provide basic file access. <itemize> <item><tt/void Open(u_long *vector)/ Open a file. Only one file can be opened at the same time. <item><tt/void Close(void)/ Close the file opened with <em/Open()/. <item><tt/void Read(void *dest, u_long length)/ Read <em/length/ bytes of data from the file opened with <em/Open/ and store them in memory starting at <em/dest/. This routine does not check whether you try to read beyond the end of the file. <item><tt/void Seek(u_long offset)/ Seek to the absolute position <em/offset/ in the file opened with <em/Open/. This routine does not check whether you try to seek beyond the end of the file. </itemize> <sect2>File execution functions These functions provide for the loading and execution of files. <itemize> <item><tt/u_long *Load(u_long *vector)/ Load a file and return a pointer to the loaded data. This function uses <em/Open()/, so it may not be called if there's already a file opened. <item><tt/void UnLoad(u_long *data)/ Unload a file loaded with <em/Load()/. <item><tt/long Exec(u_long *data, long arg)/ Execute a block of code pointed to by <em/data/. It pushes all caches first and passes the supplied <em/arg/ in register <em/D0/ and returns the return code after execution. </itemize> <sect1>The tagged map file format<label id="sec:tags"> The map file <tt>/boot/map</tt> consists of a concatenation of <em/tag records/. A tag record contains a <em/Tag/, indicating its type, a <em/Size/ (must be a multiple of 4 bytes) and <em/Size/ bytes of data. This makes the file format very simple to understand and easy to parse and extend. <sect2>General structure The general structure of the map file looks like: \begin{center/ \begin{tabular/{|l|r|l|l|/ \hline Tag & Size & Data & Info \ \hline \hline \multicolumn{4/{|c|/{<bf/File identification// \ \hline TAG_LILO & 0 & --- & \ \hline \hline \multicolumn{4/{|c|/{<bf/Boot options// \ \hline TAG_HEADER & 0 & --- & \ \multicolumn{3/{|c|/{\vdots/ & <em/Boot option tags/ \ TAG_HEADER_END & 0 & --- & \ \hline \hline \multicolumn{4/{|c|/{<bf/One or more boot records// \ \hline TAG_BOOT_RECORD & ? & char [] & Boot record label \ \multicolumn{3/{|c|/{\vdots/ & <em/Boot record tags/ \ TAG_BOOT_RECORD_END & 0 & --- & \ \hline \multicolumn{4/{c/{\vdots/ \ \hline \multicolumn{4/{|c|/{<bf/Zero or more file definitions// \ \hline TAG_FILE_DEF & ? & char [] & File name \ \multicolumn{3/{|c|/{\vdots/ & <em/File definition tags/ \ TAG_FILE_DEF_END & 0 & --- & \ \hline \multicolumn{4/{c/{\vdots/ \ \hline \multicolumn{4/{|c|/{<bf/End of file// \ \hline TAG_EOF & 0 & --- & \ \hline \end{tabular/ \end{center/ <sect2>Boot option tags \begin{center/ \begin{tabular/{|l|r|l|p{34mm/|/ \hline Tag & Size & Data & Info \ \hline \hline TAG_DEFAULT & ? & char [] & Default boot image \ TAG_AUTO & 4 & u_long & Automatic boot flag \ TAG_TIME_OUT & 4 & u_long & Time out value \ TAG_AUX & 4 & u_long & Auxiliary console \ TAG_BAUD & 4 & u_long & Baud for auxiliary console \ TAG_MASTER_PASSWORD & ? & char [] & Master password \ TAG_DEBUG & 4 & u_long & Debug flag \ TAG_PROMPT & ? & char [] & Boot prompt \ TAG_KICKRANGE & 4 & u_short [2] & Valid <em/Kickstart/ version range \ \hline \end{tabular/ \end{center/ <sect2>Boot record tags \begin{center/ \begin{tabular/{|l|r|l|l|/ \hline Tag & Size & Data & Info \ \hline \hline TAG_ALIAS & ? & char [] & Alias label name \ TAG_OS_TYPE & 4 & u_long & operating system type \ TAG_KERNEL & ? & char [] & Kernel image \ TAG_ARGUMENTS & ? & char [] & Boot arguments \ TAG_PASSWORD & ? & char [] & Password \ TAG_CHIP_RAM_SIZE & 4 & u_long & Chip RAM size \ TAG_FAST_RAM_CHUNK & 8 & u_long [2] & Fast RAM chunk \ TAG_MODEL & 4 & u_long & Amiga model \ TAG_RAMDISK & ? & char [] & Ramdisk image \ \hline \end{tabular/ \end{center/ <sect2>File definition tags \begin{center/ \begin{tabular/{|l|r|l|l|/ \hline Tag & Size & Data & Info \ \hline \hline TAG_VECTOR & ? & u_long [] & File vector \ \hline \end{tabular/ \end{center/ <sect2>Debugging You can examine the contents of a map file with the <tt/dumpmapfile/ utility. <sect1>Booting Linux/m68k If the user wants to boot Linux/m68k, the loader calls an adapted version of the <em/Amiboot/ utility. If this fails, it returns <tt/FALSE/ to the boot code. <sect1>Booting <em/AmigaOS/ If the user wants to boot <em/AmigaOS/, the loader just returns <tt/TRUE/ and the boot code uses the default boot method. <sect1><em/Lilo/ alert codes The following alert codes are used by <em/Lilo/: <descrip> <tag/<tt>30000001</tt>/ Boot error when automatic boot <tag/<tt>CC010000</tt>/ No memory <tag/<tt>CC010007</tt>/ No screen <tag/<tt>CC01000B</tt>/ No window <tag/<tt>CC038002</tt>/ No <em/graphics.library/ <tag/<tt>CC038004</tt>/ No <em/intuition.library/ <tag/<tt>CC03800A</tt>/ No <em/expansion.library/ <tag/<tt>CC040000</tt>/ No alternate boot device <tag/<tt>CC048011</tt>/ No <em/console.device/ <tag/<tt>CC048013</tt>/ No <em/keyboard.device/ <tag/<tt>CC048015</tt>/ No <em/timer.device/ <tag/<tt>CC048035</tt>/ No <em/input.device/ <tag/<tt>CC060000</tt>/ Read error <tag/<tt>CC070000</tt>/ No signal <tag/<tt>CC4D4150</tt>/ Corrupt map file </descrip> Other alert codes (especially those of the form <tt/8000000x/, with <tt/x/ equal to <tt/3/, <tt/4/, <tt/A/ or <tt/B/) may indicate that something went wrong with the <em/Lilo/ installation, e.g. you forgot to rerun <tt/lilo/ after you changed some important files.  <sect>Credits <itemize> <item>The Amiga Linux/m68k Loader was written by Geert Uytterhoeven (<htmlurl url="mailto:Geert.Uytterhoeven@cs.kuleuven.ac.be" name="Geert.Uytterhoeven@cs.kuleuven.ac.be">). <item>The Linux/m68k bootstrap code was taken from: <quote> <em/Amiboot/: This program loads the Linux/m68k kernel into an <em/Amiga/ and launches it. © Copyright 1993, 1994 by Hamish Macdonald (<htmlurl url="mailto:hamish@border.ocunix.on.ca" name="hamish@border.ocunix.on.ca">), Greg Harp (<htmlurl url="mailto:harp@netcom.com" name="harp@netcom.com">). </quote> <item>Janos Farkas (<htmlurl url="mailto:chexum@sparta.banki.hu" name="chexum@sparta.banki.hu">) added cache fixes for <em/Kickstart V36/ (<em/A3000 Beta ROM/) to and made some optimizations in the boot block code. <item>The following people inspired me with their comments: <itemize> <item>Jörg Mayer (<htmlurl url="mailto:jmayer@informatik.uni-kl.de" name="jmayer@informatik.uni-kl.de">) <item>Jörg Dorchain (<htmlurl url="mailto:dorchain@cscip.uni-sb.de" name="dorchain@cscip.uni-sb.de">) <item>Christof Damian (<htmlurl url="mailto:cdamian@mediaconsult.com" name="cdamian@mediaconsult.com">) </itemize> <item>The original idea for this program comes from the <em/Linux/ distribution: <quote> <em/LILO/: Generic Boot Loader for <em/Linux/ (<em/LInux LOader/) by Werner Almesberger (<htmlurl url="mailto:werner.almesberger@lrc.di.epfl.ch" name="werner.almesberger@lrc.di.epfl.ch">). </quote> <item>The <tt/rlatex/ script was taken from the <em/LILO/ distribution and is © Copyright 1992-1996 Werner Almesberger. </itemize> And of course I want to thank the whole <em/Linux/ community, especially the other Linux/m68k guys, for this great <em/Operating System/ (Note the uppercase `O' and `S'. IMHO <em/icrosoft/ should refer to <em/indows 95/ with <em/perating ystem/~:-)  <sect>The <em/GNU General Public License/ The Amiga Linux/m68k Loader and its documentation are © Copyright 1995 by Geert Uytterhoeven. However, they are also subject to the terms and conditions of the <em/GNU General Public License/. See the file <tt/COPYING/ for more details.  <sect>The <em/Amiga/ boot process<label id="apx:booting"> An <em/Amiga/ can boot from different devices. After initialization of all internal (motherboard) and external (<em/Zorro II/III/ boards) devices, a list of bootable devices is created, sorted by boot priority. This list can be modified using the system boot menu (The system boot menu is invoked by holding both the left and right mouse buttons at boot up.). The first floppy drive (<tt/DF0:/) always has boot priority 5, while the default boot priority of a hard drive partition is 0. Then the system tries to boot from the bootable devices in the list, the one after the other starting with the device with the highest boot priority, until success. If all failed, the system asks the user to insert a floppy by displaying an image or animation. On succes, the system boots. A device is a candidate for booting if it's marked as bootable and if one of the following conditions is met: <itemize> <item>The device has a valid file system (i.e. its <em/DosType/ is the same as that of a <em/ROM/ file system or a file system that's stored in the <em/Rigid Disk Block/ of one of the hard drives) and the file system could be initialized for this device. This should be the case for your default <em/AmigaOS/ boot partition. <item>There is no valid file system for the device. This is the case if you specify <tt/0x45585432/ (<tt/EXT2/ in <em/HEX ASCII/) for the <em/DosType/ and there is no file system in a <em/Rigid Disk Block/ with <em/DosType/ <tt/0x45585432/. </itemize> There are two ways to boot from a boot device: with or without execution of the boot block (The boot block is the first block --- actually the first $n$ blocks, with default $n = 2$. Since the default block size under <em/AmigaOS/ is 512 bytes, the default boot block size is 1024 bytes --- of the device, which has a special purpose.): <itemize> <item>Without execution of the boot block the system just ignores the boot block contents and uses the default boot method. This is the default behavior for hard drive partitions, which can be overridden by enabling <em/Custom Boot Code/ for the partition. <item>With execution of the boot block the system loads the boot block and calculates a checksum value. If the checksum is correct, the boot code in the boot block is executed, with the <em/BootRequest/ (of type <tt/struct IOStdReq/) for the boot device passed to it as a parameter. If the checksum is incorrect, the boot process fails for this device. This is the default behavior for the floppy drive and the behavior for hard drive partitions if <em/Custom Boot Code/ is enabled. <em/Lilo/ uses this method too. </itemize> The default boot method --- this method is also used in the default boot code for floppies --- just checks whether <em/dos.library/ is resident and returns a pointer to the initialization routine of <em/dos.library/.  <sect>History <sect1>Version 0.1 <itemize> <item>Initial `alpha' release with support for only one kernel image at the same time. </itemize> <sect1>Version 0.2 <itemize> <item>Addition of the configuration file. <item>Support for multiple kernel images and command lines. </itemize> <sect1>Version 0.3 <itemize> <item>Handles files with holes. <item>Fixes for <em/Kickstart V36/ (<em/A3000 Beta ROM/). <item>Debug option. <item>Rounds memory chunks to a multiple of 256K instead of 1M (for e.g. users of the <em/A3640 MapROM/ feature). </itemize> <sect1>Version 0.4 <itemize> <item>Support added for a terminal connected to the builtin serial port. <item>Documentation in LaTeX 2e. </itemize> <sect1>Version 0.4a <itemize> <item>Recompile to compensate for the changes in <tt><asm/bootinfo.h></tt>. </itemize> <sect1>Version 0.5 <itemize> <item><em/Seek()/ function added to the boot library. <item>Bootstrap code updated to the <em/Amiboot/ 2.1 level: <itemize> <item>Support added for <em/ELF/ kernels, <item>Support added for <em/a.out ZMAGIC/ kernels. </itemize> <item><em/LoadSeg()/ and <em/UnLoadSeg()/ functions of the boot library are replaced by <em/Load()/ and <em/UnLoad()/. <item><tt>/boot/loader</tt> is no longer an <em/AmigaOS/ executable. Now it's a raw PC-relative executable created with the normal <em/cc1/ of <em/m68k-linux-gcc/ 2.7.x and the <tt/fixpic/ <em/perl/ script. As a consequence you no longer need <em/gcc/ under <em/AmigaOS/ or a cross-compiler to create it. Another step in the direction of an <em/AmigaOS/-free Amiga~:-) <item>New configuration file format with additional options: <descrip> <tag/<tt>baud</tt>:/ Serial terminal speed, <tag/<tt>altdev</tt>:/ Alternate boot device, <tag/<tt>default</tt>:/ Default boot operating system. </descrip> </itemize> <sect1>Version 0.6 <itemize> <item>New options for the configuration file: <descrip> <tag/<tt>chipram</tt>:/ <em/Chip RAM/ size, <tag/<tt>fastram</tt>:/ <em/Fast RAM/ address and size. <tag/<tt>model</tt>:/ Amiga model. </descrip> <item>Now <em/Amiboot/ and <em/Lilo/ use the same bootstrap code to ease code maintenance. <item>Changed the data block size from 512 to 1024 bytes. <item>New command line option <tt/--checksum/. </itemize> <sect1>Version 0.7 (internal version) <itemize> <item>New tagged file format for <tt>/boot/map</tt>; included <tt/dumptagfile.c/ for debugging. <item>New command line option <tt/--root/. <item>New options for the configuration file: <descrip> <tag/<tt>prompt</tt>:/ Loader prompt, <tag/<tt>alias</tt>:/ Alias label for a boot record, <tag/<tt>ramdisk</tt>:/ File containing a file system to be used as a ramdisk. </descrip> <item><em/Lilo/ now knows the version of <em/Amiboot/ it's compatible with. <item>Implicit kernel command line options <tt/BOOT_IMAGE=/<tt/label/ and <tt/auto/ added. </itemize> <sect1>Version 0.8 (internal version) <itemize> <item>Now <em/Lilo/ also works under Linux/m68k 1.3.x or higher. <item>Support added for gzipped kernel images and ramdisks. <item>Addition of a boot monitor. <item>Now all file vectors are stored only once in the map file. <item>New options for the configuration file: <descrip> <tag/<tt>kickrange</tt>:/ Specify the valid <em/Kickstart/ version range, <tag/<tt>file</tt>:/ Add your own files to the map file. </descrip> <item>Included <tt/fakeboot.c/ for debugging. </itemize> <sect1>Version 1.0 <itemize> <item><tt/fixpic/ is dead, long live <tt/m68k-cbm-amigados-gcc/! <tt>/boot/loader</tt> is again an <em/AmigaOS/ executable. <item>Support for gzipped kernel images and ramdisks removed because it doesn't work with <tt/m68k-cbm-amigados-gcc/. <item>Automatic creation of a boot block backup for easy uninstalling. <item>New command line options <tt/--backup/, <tt/--uninstall/ and <tt/--version/. </itemize> </article>