| 1 | ; AiR-BOOT (c) Copyright 1998-2008 M. Kiewitz | 
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| 2 | ; | 
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| 3 | ; This file is part of AiR-BOOT | 
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| 4 | ; | 
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| 5 | ; AiR-BOOT is free software: you can redistribute it and/or modify it under | 
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| 6 | ;  the terms of the GNU General Public License as published by the Free | 
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| 7 | ;  Software Foundation, either version 3 of the License, or (at your option) | 
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| 8 | ;  any later version. | 
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| 9 | ; | 
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| 10 | ; AiR-BOOT is distributed in the hope that it will be useful, but WITHOUT ANY | 
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| 11 | ;  WARRANTY: without even the implied warranty of MERCHANTABILITY or FITNESS | 
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| 12 | ;  FOR A PARTICULAR PURPOSE. See the GNU General Public License for more | 
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| 13 | ;  details. | 
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| 14 | ; | 
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| 15 | ; You should have received a copy of the GNU General Public License along with | 
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| 16 | ;  AiR-BOOT. If not, see <http://www.gnu.org/licenses/>. | 
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| 17 | ; | 
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| 18 | ;--------------------------------------------------------------------------- | 
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| 19 | ;                                                  AiR-BOOT / LINUX SUPPORT | 
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| 20 | ;--------------------------------------------------------------------------- | 
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| 21 |  | 
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| 22 | ; Here is the startup-code for Linux-Kernels. I'm sure this won't work on | 
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| 23 | ; all of them, but on the latest. | 
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| 24 |  | 
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| 25 | ; Note: This code will ONLY WORK on computers with INT 13h Extension. | 
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| 26 | ;       I did not want to code silly cylinder stuff here and if you don't | 
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| 27 | ;       have INT 13h Extensions, you will not need this. LINUXIMG won't work | 
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| 28 | ;       without them. | 
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| 29 | ; | 
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| 30 | ; And another note: *F**k* Linux usenet-users. Really. I mean *f**k them*. | 
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| 31 | ;  I asked in an OS/2 newsgroup for testers -> Got 8 volunteers within some | 
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| 32 | ;  days. I asked in 2 Linux newsgroups. What did happen? Some idiots discussed | 
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| 33 | ;  the whole sh*t with me, knew nothing about INT13h CHS/LBA mode, BIOS, | 
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| 34 | ;  boot-managers in general, assembly coding and other stuff and wanted to tell | 
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| 35 | ;  me that 95k GRUB is well-coded and its good to have it placed all over your | 
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| 36 | ;  harddrive and that file-support and all those lousy features would waste | 
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| 37 | ;  sooo much space. ROFLMAO. | 
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| 38 | ; | 
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| 39 | ; I could implement some more file-systems into AiR-BOOT, but instead I did | 
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| 40 | ;  some nice menus, setup, text, cyrillic support, demo-coder effects, easy | 
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| 41 | ;  handling, help, auto-detection and plenty of other stuff INTO AROUND 25k. | 
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| 42 | ; | 
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| 43 | ; Oh, why is this code here? Because of 2 friends of mine. Otherwise I wouldnt | 
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| 44 | ;  have done it as well as fat16.asm. | 
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| 45 |  | 
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| 46 | IFDEF   MODULE_NAMES | 
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| 47 | DB 'LINUX',0 | 
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| 48 | ENDIF | 
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| 49 |  | 
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| 50 | Linux_TranslateBase     db '/dev/hd' | 
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| 51 | Linux_KernelDirectory   db 'KERNELS    ' | 
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| 52 |  | 
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| 53 | ; Translates partition-number to Linux-device name (e.g. /dev/hda3) | 
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| 54 | ;        In: DL - partition number, ES:DI - destination 9-byte buffer | 
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| 55 | ;       Out: (buffer filled) | 
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| 56 | ; Destroyed: None | 
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| 57 | LINUX_TranslateToDEV            Proc Near  Uses eax ebx cx dx ds si | 
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| 58 | ; Damn Linux. Our logic is as follows: first get the drive letter. | 
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| 59 | ;             that's easy. Now search our partition-table for new | 
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| 60 | ;             extended partitions and fix them up. Stupid logic. | 
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| 61 | push    cs | 
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| 62 | pop     ds                 ; CS == DS | 
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| 63 | mov     si, offset Linux_TranslateBase | 
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| 64 | mov     cx, 7 | 
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| 65 | rep     movsb                         ; First write base-name (/dev/hd)... | 
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| 66 | ; First get our partition-table | 
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| 67 | call    PART_GetPartitionPointer      ; Partition (DL) -> CS:SI | 
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| 68 | mov     dl, ds:[si+LocIPT_Drive] | 
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| 69 | mov     al, dl | 
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| 70 | sub     al, 1Fh                       ; Generate letter from drive (80h -> 61h) | 
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| 71 | stosb                                 ; write letter | 
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| 72 |  | 
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| 73 | ; Now get the linux local partition number | 
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| 74 | ; 1. Search for partition, where TranslateDrive (DL) got used first | 
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| 75 | mov     cx, si          ; CX - Searched partition offset | 
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| 76 | mov     si, offset PartitionTable ; begin here | 
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| 77 | LTTD_SearchDriveLoop: | 
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| 78 | cmp     ds:[si+LocIPT_Drive], dl | 
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| 79 | je      LTTD_SearchDrive_Found | 
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| 80 | add     si, LocIPT_LenOfIPT | 
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| 81 | jmp     LTTD_SearchDriveLoop | 
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| 82 | LTTD_SearchDrive_Found: | 
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| 83 | ; Now count all partitions to hit. After root partition set counter to | 
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| 84 | ; 4 and count further. | 
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| 85 | xor     dh, dh          ; Linux Partition Counter (Base 0) | 
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| 86 | LTTD_SearchPart_Loop: | 
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| 87 | inc     dh           ; Increase Linux Local Partition Number | 
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| 88 | mov     ax, wptr ds:[si+LocIPT_AbsolutePartTable+2] | 
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| 89 | shr     eax, 16 | 
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| 90 | mov     ax, wptr ds:[si+LocIPT_AbsolutePartTable+0] ; -> EAX | 
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| 91 | cmp     dh, 4                      ; over root partition yet ? | 
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| 92 | ja      LTTD_ContinueLoop ; yes, continue loop | 
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| 93 | cmp     eax, 0                     ; not in root partition anymore? | 
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| 94 | je      LTTD_ContinueLoop | 
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| 95 | mov     dh, 5                      ; nope, so adjust counter | 
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| 96 | LTTD_ContinueLoop: | 
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| 97 | cmp     si, cx | 
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| 98 | je      LTTD_SearchPart_Found | 
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| 99 | add     si, LocIPT_LenOfIPT           ; Next Partition | 
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| 100 | jmp     LTTD_SearchPart_Loop | 
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| 101 |  | 
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| 102 | LTTD_SearchPart_Found: | 
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| 103 | or      eax, eax | 
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| 104 | jnz     LTTD_SearchPart_NotRootPartition | 
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| 105 | ; Bullshit, it's in the MBR, so we have to look for the | 
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| 106 | ; partition number directly (because EXTEND, EXT2: EXT2 would be | 
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| 107 | ; partition 1, in fact it would be partition 2) | 
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| 108 | ; All we do here is to load the MBR to memory (suck) and look in it | 
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| 109 | ; manually. Pervertly this could be crazy, when user | 
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| 110 | ; is in setup and changing 'Linux Root'. | 
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| 111 | mov     ax, wptr ds:[si+LocIPT_AbsoluteBegin+2] | 
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| 112 | shr     eax, 16 | 
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| 113 | mov     ax, wptr ds:[si+LocIPT_AbsoluteBegin+0] ; -> EAX | 
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| 114 | push    eax | 
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| 115 | xor     ax, ax | 
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| 116 | xor     bx, bx | 
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| 117 | mov     cx,  1 | 
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| 118 | xor     dh, dh | 
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| 119 | mov     si, offset TmpSector | 
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| 120 | call    DriveIO_LoadSector         ; Load fucking MBR | 
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| 121 | pop     eax | 
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| 122 | xor     dh, dh                        ; Reset again to zero | 
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| 123 | add     si, 446 | 
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| 124 | LTTD_SearchRoot_Loop: | 
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| 125 | cmp     bptr ds:[si+4], 0 | 
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| 126 | je      LTTD_SearchRoot_NoPart     ; if partition... | 
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| 127 | inc     dh                                   ;  add one | 
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| 128 | LTTD_SearchRoot_NoPart: | 
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| 129 | mov     bx, wptr ds:[si+10] | 
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| 130 | shr     ebx, 16 | 
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| 131 | mov     bx, wptr ds:[si+08]                  ; -> EBX (Start Sector) | 
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| 132 | add     si, 16 | 
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| 133 | cmp     eax, ebx | 
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| 134 | jne     LTTD_SearchRoot_Loop | 
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| 135 |  | 
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| 136 | LTTD_SearchPart_NotRootPartition: | 
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| 137 | mov     al, dh | 
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| 138 | ; Now convert that crap (AL) to ascii and write it | 
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| 139 | cmp     al, 10 | 
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| 140 | jb      LTTD_Smaller10 | 
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| 141 | xor     ah, ah | 
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| 142 | mov     dl, 10 | 
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| 143 | div     dl | 
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| 144 | add     al, 30h         ; Generate number from value 00h -> 30h) | 
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| 145 | stosb | 
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| 146 | mov     al, ah | 
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| 147 | LTTD_Smaller10: | 
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| 148 | add     al, 30h         ; Generate number from value | 
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| 149 | stosb | 
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| 150 | ret | 
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| 151 | LINUX_TranslateToDEV            EndP | 
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| 152 |  | 
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| 153 | LINUX_InitFAT16access           Proc Near  Uses es | 
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| 154 | mov     dl, ds:[CFG_LinuxKrnlPartition] | 
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| 155 | call    PART_GetPartitionPointer      ; Partition DL -> SI | 
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| 156 | call    FAT16_InitAccess | 
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| 157 |  | 
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| 158 | call    FAT16_ReadRoot | 
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| 159 |  | 
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| 160 | mov     cx, FAT16_NumOfRootEntries | 
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| 161 | mov     si, offset Linux_KernelDirectory | 
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| 162 | call    FAT16_SearchEntry            ; Fills up DX as Cluster-No | 
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| 163 | or      dx, dx | 
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| 164 | jz      LIFAT16A_NoDirectory | 
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| 165 |  | 
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| 166 | mov    ax, 9000h | 
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| 167 | mov    es, ax | 
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| 168 | xor    di, di                      ; Read Cluster DX to 9000:0 (ES:DI) | 
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| 169 | call   FAT16_ReadCluster | 
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| 170 | mov    ax, cs | 
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| 171 | mov    es, ax                      ; DS == ES == CS | 
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| 172 | call   FAT16_ProcessKrnlDirectory | 
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| 173 |  | 
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| 174 | LIFAT16A_NoDirectory: | 
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| 175 | ret | 
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| 176 | LINUX_InitFAT16access           EndP | 
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| 177 |  | 
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| 178 | ; Initialize FAT-16 access on specified partition (required for following xs) | 
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| 179 | ;        In: DS:SI - 11-Byte Kernel Name to search | 
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| 180 | ;       Out: DL    - FFh - if not found, otherwise the entry no is replied | 
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| 181 | ; Destroyed: None | 
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| 182 | LINUX_SearchKernelName          Proc Near  Uses cx di | 
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| 183 | mov     dl, 0FFh                      ; Nothing found is default... | 
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| 184 | mov     cl, LINUX_KernelNo | 
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| 185 | or      cl, cl | 
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| 186 | jz      LSKN_NotFound | 
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| 187 | mov     di, offset LINUX_KernelEntries | 
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| 188 | add     di, LocIPT_Name | 
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| 189 | LSKN_SearchLoop: | 
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| 190 | push    cx | 
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| 191 | push    si | 
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| 192 | push    di | 
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| 193 | mov     cx, 11 | 
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| 194 | repe    cmpsb                   ; Compare total 11-bytes | 
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| 195 | pop     di | 
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| 196 | pop     si | 
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| 197 | pop     cx | 
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| 198 | je      LSKN_Found | 
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| 199 | add     di, LocIPT_LenOfIPT | 
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| 200 | dec     cl | 
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| 201 | jnz     LSKN_SearchLoop | 
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| 202 | jmp     LSKN_NotFound | 
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| 203 |  | 
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| 204 | LSKN_Found: | 
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| 205 | mov     si, di | 
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| 206 | sub     si, LocIPT_Name               ; Back to Base-Pointer | 
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| 207 | call    PART_GetPartitionNumber       ; Get Number of Entry at [SI] | 
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| 208 | LSKN_NotFound: | 
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| 209 | ret | 
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| 210 | LINUX_SearchKernelName          EndP | 
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| 211 |  | 
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| 212 | Linux_FuzzyString       db 'Linux Boot - Alpha', 13, 10, 0 | 
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| 213 | Linux_GotBadKernel      db ' - Bad Kernel/Bad FAT-16 partition', 0 | 
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| 214 | Linux_INT15error        db ' - INT 15 error', 0 | 
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| 215 | Linux_RootDefine        db 'root=' | 
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| 216 |  | 
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| 217 | LINUX_LoadKernel                Proc Near  Uses ; Direct Jump, No Preserves | 
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| 218 | ; TranslateToDev needs UNFILTERED Partition Pointers... | 
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| 219 | call    PART_CalculateStraightPartPointers | 
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| 220 | push    si | 
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| 221 | mov     si, offset Linux_FuzzyString | 
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| 222 | call    MBR_Teletype | 
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| 223 | pop     si | 
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| 224 | ; DX - Starting-Cluster of Linux Kernel File | 
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| 225 | mov     dx, ds:[si+LocIPT_LocationBegin] | 
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| 226 | ; from now on, we don't need si anymore | 
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| 227 |  | 
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| 228 | ; Linux has 1 'BR' (which is crap) and some setup sectors | 
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| 229 | ; we load them at 9000:0, what a luck, we are at 8000:0 :-)) | 
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| 230 | push    ds | 
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| 231 | push    es | 
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| 232 | mov     ax, 9000h | 
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| 233 | mov     es, ax | 
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| 234 | xor     di, di | 
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| 235 | call    FAT16_ReadCluster          ; Load First Cluster (DX) to 9000:0 | 
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| 236 | mov     cl, bptr es:[01F1h]        ; Setup sectors to load | 
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| 237 | inc     cl                         ; Total sectors to load to 9000:0 | 
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| 238 | jmp     LLL_CheckLeft | 
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| 239 |  | 
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| 240 | LLL_LoadSetupCodeLoop: | 
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| 241 | call    FAT16_ReadCluster | 
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| 242 | LLL_CheckLeft: | 
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| 243 | sub     cl, FAT16_SecsPerCluster | 
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| 244 | jz      LLL_GotAllClusterDone | 
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| 245 | jc      LLL_GotAllClusterNotEmpty | 
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| 246 | jmp     LLL_LoadSetupCodeLoop | 
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| 247 |  | 
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| 248 | LLL_GotAllClusterDone: | 
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| 249 | xor     cx, cx | 
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| 250 | jmp     LLL_GotAll | 
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| 251 | LLL_GotAllClusterNotEmpty: | 
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| 252 | ; Damn, Cluster didn't got empty. So we have to copy the rest out... | 
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| 253 | xor     ch, ch | 
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| 254 | not     cl | 
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| 255 | inc     cl                         ; 0FFh -> 1 sector to get... | 
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| 256 | ; Now copy rest to 6000:0 location for later processing... | 
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| 257 | ; ES:DI - Ending location of Setup Code | 
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| 258 | mov     ax, 9000h | 
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| 259 | mov     ds, ax | 
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| 260 | mov     ax, 6000h | 
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| 261 | mov     es, ax | 
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| 262 | ; Push Kernel-Entry-Pointer | 
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| 263 | push    cx | 
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| 264 | push    si | 
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| 265 | mov     si, di | 
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| 266 | shl     cx, 9                   ; Sectors to Byte Count | 
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| 267 | sub     si, cx                  ; DS:SI - Begin of Kernel Data | 
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| 268 | xor     di, di | 
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| 269 | shr     cx, 1 | 
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| 270 | rep     movsw                   ; Copy Data... | 
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| 271 | ; Get Kernel-Entry-Pointer back | 
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| 272 | pop     si | 
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| 273 | pop     cx | 
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| 274 | LLL_GotAll: | 
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| 275 | pop     es | 
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| 276 | pop     ds | 
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| 277 |  | 
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| 278 | ; Push Missing-Sectors, StartCluster | 
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| 279 | push    cx | 
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| 280 | push    dx | 
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| 281 | mov     ax, 9000h | 
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| 282 | mov     ds, ax | 
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| 283 |  | 
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| 284 | ; Check Signatures for security... | 
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| 285 | cmp     wptr ds:[1FEh], 0AA55h | 
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| 286 | jne     LLL_BadKernel | 
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| 287 | cmp     wptr ds:[202h], 'dH' | 
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| 288 | jne     LLL_BadKernel | 
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| 289 | cmp     wptr ds:[204h], 'Sr' | 
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| 290 | je      LLL_GoodKernel | 
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| 291 | LLL_BadKernel: | 
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| 292 | push    es | 
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| 293 | pop     ds | 
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| 294 | mov     si, offset Linux_GotBadKernel | 
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| 295 | call    MBR_Teletype | 
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| 296 | jmp     MBR_HaltSystem | 
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| 297 | LLL_GoodKernel: | 
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| 298 |  | 
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| 299 | ; Now we have at least some of the required sectors loaded | 
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| 300 | mov     ax, 9000h | 
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| 301 | mov     dx, ax | 
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| 302 | mov     al, bptr ds:[01F1h]         ; Setup Sectors to load | 
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| 303 | ;   -> to 9020:0 | 
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| 304 |  | 
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| 305 | ; Just append parameters to end of Linux boot-block... | 
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| 306 | xor     ah, ah | 
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| 307 | mov     bl, 20h | 
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| 308 | mul     bl           ; AX * 20 | 
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| 309 | add     dx, ax       ; add to segment    -> Segment of Parameters | 
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| 310 |  | 
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| 311 | mov     wptr ds:[0020h], 0A33Fh | 
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| 312 | mov     ax, dx | 
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| 313 | and     ax, 0FFFh                   ; 9100h -> 0100h | 
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| 314 | shl     ax, 4                       ; 0100h -> 1000h | 
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| 315 | mov     wptr ds:[0022h], ax         ; offset of parameter relative 9000:0 | 
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| 316 |  | 
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| 317 | ; fill out Linux-Loader byte, so SETUP will do its job | 
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| 318 | mov     bptr ds:[0210h], 0A0h       ; AiR-BOOT (unknown ID for Linux btw) | 
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| 319 | mov     cx, wptr ds:[01F4h]         ; Linux Kernel Length in 16-byte blocks | 
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| 320 | shr     cx, 5 | 
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| 321 | inc     cx                          ; Convert to Sector-Count | 
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| 322 | push    cx | 
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| 323 | push    cs | 
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| 324 | pop     ds                       ; CS == DS | 
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| 325 | mov     es, dx                   ; ES = Segment for parameters | 
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| 326 | xor     di, di                   ; ES:0 - Parameter Ptr | 
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| 327 | mov     dl, cs:[CFG_LinuxRootPartition] | 
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| 328 | cmp     dl, 0FFh | 
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| 329 | je      LLL_NoRootPartitionFound | 
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| 330 | mov     cx, 5 | 
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| 331 | mov     si, offset Linux_RootDefine | 
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| 332 | rep     movsb                    ; root= | 
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| 333 | call    LINUX_TranslateToDEV     ; Writes DEV (dl) at ES:DI (/dev/hda9) | 
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| 334 |  | 
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| 335 | LLL_NoRootPartitionFound: | 
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| 336 | ; Root-Define complete, now for the user Kernel Command-Line... | 
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| 337 | mov     si, offset CFG_LinuxCommandLine | 
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| 338 | mov     al, ds:[si] | 
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| 339 | or      al, al | 
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| 340 | jz      LLL_CommandLineLoop | 
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| 341 | mov     al, ' ' | 
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| 342 | stosb                            ; If any command-line, insert space | 
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| 343 | LLL_CommandLineLoop: | 
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| 344 | lodsb | 
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| 345 | stosb                         ; Copy string till and including NUL | 
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| 346 | or      al, al | 
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| 347 | jnz     LLL_CommandLineLoop | 
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| 348 | stosb                            ; Write another NUL | 
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| 349 | pop     cx | 
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| 350 | ; Pop StartCluster, Missing-Sectors | 
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| 351 | pop     dx | 
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| 352 | pop     bx | 
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| 353 | ; CX - Sector-Count of Kernel Image, DX - Starting Cluster of Kernel Image | 
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| 354 | ; BX - Sector-Count left over in 6000:0 area from Setup Code loading | 
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| 355 | ; DS == CS | 
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| 356 |  | 
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| 357 | ; Now comes some tricky part. Hopefully we have a tiny kernel. | 
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| 358 | ; If we have a big kernel, we have to 'upload' it to PM-memory space. | 
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| 359 | test    bptr ds:[0211h], 01h | 
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| 360 | jz      LLL_LoadNormalKernel | 
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| 361 | jmp     LLL_LoadBigKernel | 
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| 362 |  | 
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| 363 | LLL_LoadNormalKernel: | 
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| 364 | ; NORMAL KERNEL | 
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| 365 |  | 
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| 366 | ; Still UNSUPPORTED. This suxxs | 
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| 367 |  | 
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| 368 | LLL_LoadBigKernel: | 
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| 369 | ; BIG KERNEL - Oh no, we have to load all data to extended memory... | 
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| 370 | mov     ax, 6000h | 
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| 371 | mov     es, ax | 
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| 372 | shr     ax, 4 | 
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| 373 | ; Set Source to 06:0000 | 
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| 374 | mov     bptr cs:[MBR_Linux_GDT_Src+0], al | 
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| 375 | mov     wptr cs:[MBR_Linux_GDT_Src+1], ax | 
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| 376 | xor     si, si | 
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| 377 | or      bx, bx                        ; No unfinished Cluster ? | 
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| 378 | jz      LLL_LoadBigKernelLoop | 
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| 379 | push    cx | 
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| 380 | mov     cx, bx | 
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| 381 | shl     cx, 8                      ; Sectors to WORD Count | 
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| 382 | call    LINUX_MoveKernelPart       ; Copy Data to Extended Memory | 
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| 383 | pop     cx | 
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| 384 | LLL_LoadBigKernelLoop: | 
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| 385 | push    cx | 
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| 386 | ; DX - Current Cluster | 
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| 387 | ; CX - Total WORDs that need to be loaded | 
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| 388 | ; ES - Segment | 
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| 389 | mov     cx, 8000h | 
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| 390 | call    LINUX_LoadDataToMemory | 
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| 391 | ; CX - Total WORDs that were loaded... | 
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| 392 | ; Got 6000:0 filled... | 
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| 393 | call    LINUX_MoveKernelPart | 
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| 394 | shr     cx, 8                      ; WORDs to SEGMENTs | 
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| 395 | add     si, cx | 
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| 396 | pop     cx | 
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| 397 | cmp     si, cx | 
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| 398 | jb      LLL_LoadBigKernelLoop | 
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| 399 |  | 
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| 400 | LLL_FinishedLoadKernel: | 
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| 401 | ; either way, we give execution to setup at 9020:0 | 
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| 402 | mov     ax, 09020h | 
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| 403 | mov     ss, ax | 
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| 404 | mov     sp, 4000h-12h   ; Linux wants it this way... | 
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| 405 | mov     ds, ax | 
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| 406 | mov     es, ax | 
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| 407 | db      0EAh | 
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| 408 | dw      0 | 
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| 409 | dw      09020h | 
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| 410 | LINUX_LoadKernel                EndP | 
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| 411 |  | 
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| 412 | ; Loads Data from Cluster(s) to memory... | 
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| 413 | ;        In: DX - First cluster to read from... | 
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| 414 | ;            CX - Total WORDs that need to be loaded at least | 
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| 415 | ;            ES - Segment, where to load to (Starting Offset is zero) | 
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| 416 | ;       Out: CX - Total WORDs that got loaded | 
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| 417 | ;            DX - Cluster following last loaded cluster | 
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| 418 | ;            (buffer filled) | 
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| 419 | ; Destroyed: None | 
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| 420 | ; MUST BE USING CS for addressing Code Segment, DS =! CS | 
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| 421 | LINUX_LoadDataToMemory          Proc Near  Uses di | 
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| 422 | shl     cx, 1                         ; Convert WORDs to BYTEs | 
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| 423 | dec     cx                            ; 0000h -> FFFFh | 
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| 424 | xor     di, di | 
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| 425 | LLDTM_LoadLoop: | 
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| 426 | call    FAT16_ReadCluster          ; Load Cluster DX to ES:DI | 
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| 427 | ; DX and DI were updated by ReadCluster, so don't modify them... | 
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| 428 | or      di, di | 
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| 429 | jz      LLDTM_Overflow | 
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| 430 | cmp     di, cx | 
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| 431 | jbe     LLDTM_LoadLoop | 
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| 432 | mov     cx, di | 
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| 433 | shr     cx, 1 | 
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| 434 | inc     cx                            ; 3FFFh -> 4000h | 
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| 435 | ret | 
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| 436 | LLDTM_Overflow: | 
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| 437 | mov     cx, 08000h | 
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| 438 | ret | 
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| 439 | LINUX_LoadDataToMemory          EndP | 
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| 440 |  | 
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| 441 | ; Copies Extended-Memory (clobbered from Linux setup) | 
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| 442 | ;        In: CX    - Total WORDs to copy | 
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| 443 | ;       Out: (buffer copied) | 
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| 444 | ; Destroyed: None | 
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| 445 | ; MUST BE USING CS for addressing Code Segment, DS =! CS | 
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| 446 | LINUX_MoveKernelPart            Proc Near  Uses ax cx es si | 
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| 447 | mov     ax, cs | 
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| 448 | mov     es, ax | 
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| 449 | mov     si, offset MBR_Linux_GDT | 
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| 450 | push    cx | 
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| 451 | mov     ax, 08700h | 
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| 452 | ;      IFDEF ReleaseCode | 
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| 453 | int     15h | 
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| 454 | jc      LMKP_Error | 
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| 455 | ;      ENDIF | 
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| 456 | pop     cx | 
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| 457 | ; now adjust Destination by copied word-count | 
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| 458 | add     wptr cs:[MBR_Linux_GDT_Dst], cx | 
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| 459 | adc     bptr cs:[MBR_Linux_GDT_Dst+2], 0 | 
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| 460 | add     wptr cs:[MBR_Linux_GDT_Dst], cx | 
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| 461 | adc     bptr cs:[MBR_Linux_GDT_Dst+2], 0 | 
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| 462 | ret | 
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| 463 | LMKP_Error: | 
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| 464 | mov     ax, cs | 
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| 465 | mov     ds, ax | 
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| 466 | mov     si, offset Linux_INT15error | 
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| 467 | call    MBR_Teletype | 
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| 468 | jmp     MBR_HaltSystem | 
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| 469 | LINUX_MoveKernelPart            EndP | 
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| 470 |  | 
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| 471 | MBR_Linux_GDT:          dw          0, 0, 0, 0 | 
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| 472 | dw          0, 0, 0, 0 | 
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| 473 | dw          0FFFFh | 
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| 474 | MBR_Linux_GDT_Src       db          0, 0, 06h    ; Source is 6000:0 | 
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| 475 | db          093h | 
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| 476 | dw          0 | 
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| 477 | dw          0FFFFh | 
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| 478 | MBR_Linux_GDT_Dst       db          0, 0, 10h    ; Dest is "10000:0" | 
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| 479 | db          093h | 
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| 480 | dw          0 | 
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| 481 | dw          0, 0, 0, 0 | 
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| 482 | dw          0, 0, 0, 0 | 
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| 483 | dw          0 | 
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| 484 |  | 
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| 485 | ; | 
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| 486 | ; Example of boot setup command under lilo prompt: | 
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| 487 | ; | 
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| 488 | ; lilo: linux root=/dev/sda2 sym53c8xx=tags:4,sync:10,debug:0x200 | 
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| 489 | ; | 
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