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/*
* (C) Copyright 2002
* Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#ifndef _BIOS_H_
#define _BIOS_H_
#define OFFS_ES 0 /* 16bit */
#define OFFS_GS 2 /* 16bit */
#define OFFS_DS 4 /* 16bit */
#define OFFS_EDI 6 /* 32bit */
#define OFFS_DI 6 /* low 16 bits of EDI */
#define OFFS_ESI 10 /* 32bit */
#define OFFS_SI 10 /* low 16 bits of ESI */
#define OFFS_EBP 14 /* 32bit */
#define OFFS_BP 14 /* low 16 bits of EBP */
#define OFFS_ESP 18 /* 32bit */
#define OFFS_SP 18 /* low 16 bits of ESP */
#define OFFS_EBX 22 /* 32bit */
#define OFFS_BX 22 /* low 16 bits of EBX */
#define OFFS_BL 22 /* low 8 bits of BX */
#define OFFS_BH 23 /* high 8 bits of BX */
#define OFFS_EDX 26 /* 32bit */
#define OFFS_DX 26 /* low 16 bits of EBX */
#define OFFS_DL 26 /* low 8 bits of BX */
#define OFFS_DH 27 /* high 8 bits of BX */
#define OFFS_ECX 30 /* 32bit */
#define OFFS_CX 30 /* low 16 bits of EBX */
#define OFFS_CL 30 /* low 8 bits of BX */
#define OFFS_CH 31 /* high 8 bits of BX */
#define OFFS_EAX 34 /* 32bit */
#define OFFS_AX 34 /* low 16 bits of EBX */
#define OFFS_AL 34 /* low 8 bits of BX */
#define OFFS_AH 35 /* high 8 bits of BX */
#define OFFS_VECTOR 38 /* 16bit */
#define OFFS_IP 40 /* 16bit */
#define OFFS_CS 42 /* 16bit */
#define OFFS_FLAGS 44 /* 16bit */
#define SEGMENT 0x40
#define STACK 0x800 /* stack at 0x40:0x800 -> 0x800 */
/* save general registers */
/* save some segments */
/* save callers stack segment .. */
/* ... in gs */
/* setup my segments */
/* setup BIOS stackpointer */
#define MAKE_BIOS_STACK \
pushal; \
pushw %ds; \
pushw %gs; \
pushw %es; \
pushw %ss; \
popw %gs; \
movw $SEGMENT, %ax; \
movw %ax, %ds; \
movw %ax, %es; \
movw %ax, %ss; \
movw %sp, %bp; \
movw $STACK, %sp
#define RESTORE_CALLERS_STACK \
pushw %gs; /* restore callers stack segment */ \
popw %ss; \
movw %bp, %sp; /* restore stackpointer */ \
popw %es; /* restore segment selectors */ \
popw %gs; \
popw %ds; \
popal /* restore GP registers */
#endif
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