| 1 | ; -*- fundamental -*- (asm-mode sucks) |
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| 2 | ; ----------------------------------------------------------------------- |
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| 3 | ; |
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| 4 | ; Copyright 1994-2009 H. Peter Anvin - All Rights Reserved |
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| 5 | ; Copyright 2009-2011 Intel Corporation; author: H. Peter Anvin |
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| 6 | ; |
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| 7 | ; This program is free software; you can redistribute it and/or modify |
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| 8 | ; it under the terms of the GNU General Public License as published by |
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| 9 | ; the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, |
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| 10 | ; Boston MA 02110-1301, USA; either version 2 of the License, or |
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| 11 | ; (at your option) any later version; incorporated herein by reference. |
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| 12 | ; |
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| 13 | ; ----------------------------------------------------------------------- |
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| 14 | |
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| 15 | ; |
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| 16 | ; diskfs.inc |
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| 17 | ; |
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| 18 | ; Common code for conventional disk-based filesystems |
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| 19 | ; |
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| 20 | |
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| 21 | ; |
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| 22 | ; Some semi-configurable constants... change on your own risk. |
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| 23 | ; |
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| 24 | NULLFILE equ 0 ; Null character == empty filename |
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| 25 | NULLOFFSET equ 0 ; Position in which to look |
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| 26 | retry_count equ 16 ; How patient are we with the disk? |
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| 27 | %assign HIGHMEM_SLOP 0 ; Avoid this much memory near the top |
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| 28 | LDLINUX_MAGIC equ 0x3eb202fe ; A random number to identify ourselves with |
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| 29 | |
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| 30 | ; This indicates the general format of the last few bytes in the boot sector |
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| 31 | BS_MAGIC_VER equ 0x1b << 9 |
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| 32 | |
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| 33 | MIN_SECTOR_SHIFT equ 9 |
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| 34 | MIN_SECTOR_SIZE equ (1 << MIN_SECTOR_SHIFT) |
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| 35 | |
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| 36 | ; --------------------------------------------------------------------------- |
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| 37 | ; BEGIN CODE |
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| 38 | ; --------------------------------------------------------------------------- |
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| 39 | |
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| 40 | ; |
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| 41 | ; Memory below this point is reserved for the BIOS and the MBR |
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| 42 | ; |
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| 43 | section .earlybss |
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| 44 | global trackbuf:data hidden |
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| 45 | trackbufsize equ 8192 |
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| 46 | trackbuf resb trackbufsize ; Track buffer goes here |
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| 47 | ; ends at 2800h |
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| 48 | |
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| 49 | ; |
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| 50 | ; Common bootstrap code for disk-based derivatives |
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| 51 | ; |
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| 52 | %include "diskstart.inc" |
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| 53 | |
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| 54 | ; |
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| 55 | ; Now, everything is "up and running"... patch kaboom for more |
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| 56 | ; verbosity and using the full screen system |
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| 57 | ; |
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| 58 | ; E9 = JMP NEAR |
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| 59 | mov di,kaboom.patch |
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| 60 | mov al,0e9h |
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| 61 | stosb |
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| 62 | mov ax,kaboom2-2 |
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| 63 | sub ax,di |
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| 64 | stosw |
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| 65 | |
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| 66 | ; |
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| 67 | ; If we get to this point ldlinux.c32 failed to run. There's nothing |
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| 68 | ; left to do but inform that user that something went wrong. |
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| 69 | ; |
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| 70 | enter_command: |
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| 71 | auto_boot: |
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| 72 | jmp kaboom |
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| 73 | |
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| 74 | section .bss16 |
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| 75 | alignb 4 |
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| 76 | ThisKbdTo resd 1 ; Temporary holder for KbdTimeout |
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| 77 | ThisTotalTo resd 1 ; Temporary holder for TotalTimeout |
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| 78 | KernelExtPtr resw 1 ; During search, final null pointer |
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| 79 | FuncFlag resb 1 ; Escape sequences received from keyboard |
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| 80 | KernelType resb 1 ; Kernel type, from vkernel, if known |
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| 81 | global KernelName |
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| 82 | KernelName resb FILENAME_MAX ; Mangled name for kernel |
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| 83 | |
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| 84 | section .text16 |
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| 85 | ; |
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| 86 | ; COM32 vestigial data structure |
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| 87 | ; |
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| 88 | %include "com32.inc" |
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| 89 | |
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| 90 | ; |
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| 91 | ; Common local boot code |
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| 92 | ; |
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| 93 | %include "localboot.inc" |
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| 94 | |
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| 95 | ; |
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| 96 | ; kaboom2: once everything is loaded, replace the part of kaboom |
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| 97 | ; starting with "kaboom.patch" with this part |
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| 98 | |
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| 99 | kaboom2: |
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| 100 | mov si,err_bootfailed |
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| 101 | pm_call pm_writestr |
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| 102 | cmp byte [kaboom.again+1],18h ; INT 18h version? |
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| 103 | je .int18 |
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| 104 | pm_call pm_getchar |
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| 105 | pm_call syslinux_force_text_mode |
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| 106 | int 19h ; And try once more to boot... |
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| 107 | .norge: jmp short .norge ; If int 19h returned; this is the end |
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| 108 | .int18: |
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| 109 | pm_call syslinux_force_text_mode |
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| 110 | int 18h |
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| 111 | .noreg: jmp short .noreg ; Nynorsk |
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| 112 | |
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| 113 | ; ----------------------------------------------------------------------------- |
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| 114 | ; Common modules |
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| 115 | ; ----------------------------------------------------------------------------- |
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| 116 | |
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| 117 | %include "common.inc" ; Universal modules |
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| 118 | |
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| 119 | ; ----------------------------------------------------------------------------- |
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| 120 | ; Begin data section |
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| 121 | ; ----------------------------------------------------------------------------- |
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| 122 | |
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| 123 | section .data16 |
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| 124 | global copyright_str |
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| 125 | copyright_str db ' Copyright (C) 1994-' |
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| 126 | asciidec YEAR |
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| 127 | db ' H. Peter Anvin et al', CR, LF, 0 |
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| 128 | err_bootfailed db CR, LF, 'Boot failed: please change disks and press ' |
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| 129 | db 'a key to continue.', CR, LF, 0 |
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| 130 | |
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| 131 | ; |
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| 132 | ; Misc initialized (data) variables |
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| 133 | ; |
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| 134 | %ifdef debug ; This code for debugging only |
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| 135 | debug_magic dw 0D00Dh ; Debug code sentinel |
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| 136 | %endif |
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