1 ; ----------------------------------------------------------------------- 2 ; 3 ; Copyright 2010 Gene Cumm 4 ; 5 ; Portions from diskstart.inc: 6 ; Copyright 1994-2009 H. Peter Anvin - All Rights Reserved 7 ; Copyright 2009-2010 Intel Corporation; author: H. Peter Anvin 8 ; 9 ; This program is free software; you can redistribute it and/or modify 10 ; it under the terms of the GNU General Public License as published by 11 ; the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, 12 ; Boston MA 02110-1301, USA; either version 2 of the License, or 13 ; (at your option) any later version; incorporated herein by reference. 14 ; 15 ; ----------------------------------------------------------------------- 16 17 ; 18 ; geodspms.asm 19 ; 20 ; Display geometry translation info for diagnosing misconceptions 21 ; multi-sector variant 22 ; 23 ; nasm -Ox -f bin -o geodsp.bin -l geodsp.lst geodsp.asm 24 ; 25 ; nasm -Ox -f elf -o geodsp.o -l geodsp.lst geodsp.asm 26 ; ld -m elf_i386 -T syslinux.ld -M -o geodsp.elf geodsp.o > geodsp.map 27 ; objcopy -O binary geodsp.elf geodsp.raw 28 ; 29 ; # OF=/dev/sdb 30 ; # dd if=core/geodsp.bin of=$OF 31 ; # dd skip=1 seek=1 if=../dbg/lba-img/lba-img.bin of=$OF 32 ; # eject $OF 33 ; # dd count=$() if=/dev/zero of=$OF 34 ; 35 ; # OF=geo-2.255.63.i 36 ; # (dd if=core/geodsp.bin; dd skip=1 if=../dbg/lba-img/lba-img.bin; dd count=$((2*255*63 - 256*63 - 1)) if=/dev/zero )|dd of=$OF 37 ; # OF=geo-20.16.63.i 38 ; # (dd if=core/geodsp.bin; dd skip=1 if=../dbg/lba-img/lba-img.bin; dd count=$((40*16*63 - 256*63 - 1)) if=/dev/zero )|dd of=$OF 39 ; 40 41 ; Just to define it to look like SYSLINUX 42 %define IS_SYSLINUX 1 43 44 %include "macros.inc" 45 ; %include "layout.inc" 46 47 m_CHS0 equ 00534843h ;'CHS',0 48 m_EDD0 equ 00444445h ;'EDD',0 49 m_EDD_SP equ 20444445h ;'EDD ' 50 retry_count equ 16 51 dbuf equ 8000h 52 ; int13_ret equ 7e00h 53 LDLINUX_MAGIC equ 0x3eb202fe ; A random number to identify ourselves with 54 55 Sect1Ptr0_VAL equ 1 56 Sect1Ptr1_VAL equ 0 57 58 ; global STACK_LEN, STACK_TOP, STACK_BASE 59 ; STACK_LEN equ 4096 60 STACK_TOP equ 7c00h 61 ; STACK_BASE equ STACK_TOP - STACK_LEN 62 section .init 63 org STACK_TOP 64 geodsp_start: 65 66 %include "diskboot.inc" 67 68 HEXDATE equ 1 69 70 section .init 71 sector_1: 72 ldlinux_sys: 73 alignz 8 74 ldlinux_magic dd LDLINUX_MAGIC 75 dd LDLINUX_MAGIC^HEXDATE 76 77 78 ldlinux_ent: 79 80 get_geo: ; DL and ES ready 81 mov ah,08h 82 mov di,0 83 call xint13 84 write_geo: 85 jc .bad_geo 86 mov si,s_chs 87 call writestr_early 88 call write_chs 89 call crlf 90 jmp short .done 91 .bad_geo: 92 .done: 93 94 mov bx,dbuf 95 get_h1c: ; 0,1,1 96 mov cx,0001h 97 mov dh,01h 98 call getonesec_chs 99 call write_chs_lba 100 get_c1c: ; 1,0,1 101 mov cx,0101h 102 mov dh,00h 103 call getonesec_chs 104 call write_chs_lba 105 106 107 108 ; Do we have EBIOS (EDD)? 109 ; 110 edd: 111 .check: 112 mov bx,55AAh 113 mov ah,41h ; EDD existence query 114 call xint13 115 jc .noedd 116 cmp bx,0AA55h 117 jne .noedd 118 test cl,1 ; Extended disk access functionality set 119 jz .noedd 120 ; 121 ; We have EDD support... 122 ; 123 mov bx,dbuf ; ES should still be safe. 124 xor edx,edx 125 mov dword [s_chs],m_EDD_SP 126 .get_lba63: 127 mov eax,63 ; Same length as mov al,64; movzx eax,al 128 call getonesec_ebios 129 jc .bad_edd ;read error 130 call write_edd_lba 131 .get_lba16065: 132 mov eax,16065 133 call getonesec_ebios 134 jc .bad_edd ;read error 135 call write_edd_lba 136 .good_edd: 137 mov dword [s_type],m_EDD0 138 .bad_edd: 139 .noedd: 140 .end: 141 142 write_final_type: 143 mov si,s_typespec 144 call writestr_early 145 jmp kaboom 146 147 ; 148 ; getonesec_chs: 149 ; 150 ; CX,DH specifies CHS address 151 ; 152 getonesec_chs: ; We could use an xchg and get a loop 153 ; mov cx,retry_count 154 .retry: 155 pushad 156 mov ax,0201h ; Read one sector 157 call xint13 158 popad 159 jc .error 160 ret 161 162 .error: 163 ; loop .retry 164 ; Fall through to disk_error 165 jmp disk_error 166 167 %include "geodsplib.inc" 168 169 ; 170 ; 171 ; writestr_early: write a null-terminated string to the console 172 ; This assumes we're on page 0. This is only used for early 173 ; messages, so it should be OK. 174 ; 175 writestr_early: 176 pushad 177 .loop: lodsb 178 and al,al 179 jz .return 180 mov ah,0Eh ; Write to screen as TTY 181 mov bx,0007h ; Attribute 182 int 10h 183 jmp short .loop 184 .return: popad 185 ret 186 187 SuperInfo: zd 32 ; The first 16 bytes expanded 8 times 188 189 ; This fails if the sector overflowsg 190 zb 400h-($-$$) 191 end: 192 193 absolute 4*1Eh 194 fdctab equ $ 195 fdctab1 resw 1 196 fdctab2 resw 1 197
