NetBSD/sys/arch/i386/pnpbios/pnpbioscall.S
2002-11-22 15:02:12 +00:00

95 lines
2.6 KiB
ArmAsm

/* $NetBSD: pnpbioscall.S,v 1.1 2002/11/22 15:02:12 fvdl Exp $ */
/*
* Copyright (c) 1999
* Matthias Drochner. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "assym.h"
#include <machine/asm.h>
#include <machine/segments.h>
.data
saveesp:
.space 4
NENTRY(pnpbioscall)
pushl %ebp
movl %esp, %ebp
/*
* disable interrupts - our handlers can't deal with frames of the
* segment we are calling, and the BIOS can't use our IDT anyway
*/
pushfl
cli
/* call pnpbiostramp() */
lcall $GSEL(GPNPBIOSTRAMP_SEL, SEL_KPL), $0
popfl
popl %ebp
ret
NENTRY(pnpbiostramp)
pushl %ebx
/* save current stack pointer */
movl %esp, %eax
movl %eax, saveesp
/* switch to new stack */
movl 8(%ebp), %esp /* call argument */
movl $GSEL(GPNPBIOSSCRATCH_SEL, SEL_KPL), %eax
mov %ax, %ss
/* fake the call return address (16-bit frame) */
mov %cs, %ax
push %ax
movl $(1f - _C_LABEL(pnpbiostramp)), %eax
push %ax
/* do a long jump */
pushl $GSEL(GPNPBIOSCODE_SEL, SEL_KPL)
pushl (_C_LABEL(pnpbios_entry))
#if 1
/* paranoia: don't pass our ds */
movl $GSEL(GPNPBIOSSCRATCH_SEL, SEL_KPL), %eax
mov %ax, %ds
#endif
lret
1: /* returned from BIOS call */
movl $GSEL(GDATA_SEL, SEL_KPL), %ebx
#if 1
mov %bx, %ds
#endif
/* back to old stack */
mov %bx, %ss
movl saveesp, %ebx
movl %ebx, %esp
popl %ebx
lret
.globl _C_LABEL(epnpbiostramp)
_C_LABEL(epnpbiostramp):