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/*
* Copyright (c) 1995 The University of Utah and
* the Computer Systems Laboratory at the University of Utah (CSL).
* All rights reserved.
*
* Permission to use, copy, modify and distribute this software is hereby
* granted provided that (1) source code retains these copyright, permission,
* and disclaimer notices, and (2) redistributions including binaries
* reproduce the notices in supporting documentation, and (3) all advertising
* materials mentioning features or use of this software display the following
* acknowledgement: ``This product includes software developed by the
* Computer Systems Laboratory at the University of Utah.''
*
* THE UNIVERSITY OF UTAH AND CSL ALLOW FREE USE OF THIS SOFTWARE IN ITS "AS
* IS" CONDITION. THE UNIVERSITY OF UTAH AND CSL DISCLAIM ANY LIABILITY OF
* ANY KIND FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* CSL requests users of this software to return to csl-dist@cs.utah.edu any
* improvements that they make and grant CSL redistribution rights.
*
* Author: Bryan Ford, University of Utah CSL
*/
#include <mach/machine/asm.h>
#include <mach/machine/eflags.h>
#include "trap.h"
#include "i386_asm.h"
#include "pc_asm.h"
#include "trap_asm.h"
.text
.globl rv86_real_int_asm
rv86_real_int_asm:
/* Stash our protected-mode stack pointer. */
movl %esp,EXT(real_tss)+TSS_ESP0
/* Load the linear/physical-address data segment into ES,
for easy access to real-mode memory. */
movl $LINEAR_DS,%edx
movw %dx,%es
/* Find the physical address of the real-mode interrupt stack (es:ebx).
A 6-byte stack frame has already been allocated on it. */
movl EXT(rv86_usp)+4,%ebx
shll $4,%ebx
addl EXT(rv86_usp),%ebx
/* Store the magic return pointer into the real-mode interrupt stack frame. */
movl EXT(rv86_rp),%edx
movl %edx,%es:(%ebx)
movw RCD_FLAGS(%eax),%dx
movw %dx,%es:4(%ebx)
/* Find the address of the real mode interrupt vector (es:esi). */
shll $2,%esi
/* Build the v86 trap frame. */
xorl %edx,%edx
movw RCD_GS(%eax),%dx
pushl %edx
movw RCD_FS(%eax),%dx
pushl %edx
movw RCD_DS(%eax),%dx
pushl %edx
movw RCD_ES(%eax),%dx
pushl %edx
pushl EXT(rv86_usp)+4
pushl EXT(rv86_usp)
movl $EFL_VM+EFL_IOPL_USER,%ecx
orw RCD_FLAGS(%eax),%cx
andl $-1-EFL_IF-EFL_TF,%ecx
pushl %ecx
movw %es:2(%esi),%edx
pushl %edx
movw %es:(%esi),%edx
pushl %edx
/* Load the requested register state. */
movl RCD_EDI(%eax),%edi
movl RCD_ESI(%eax),%esi
movl RCD_EBP(%eax),%ebp
movl RCD_EBX(%eax),%ebx
movl RCD_EDX(%eax),%edx
movl RCD_ECX(%eax),%ecx
movl RCD_EAX(%eax),%eax
/* Drop into v86 mode. */
iret
ENTRY(rv86_return)
/* Restore the kernel segment registers. */
movw %ss,%ax
movw %ax,%ds
movw %ax,%es
/* Retrieve the real_call_data pointer from rv86_real_int_asm's stack frame. */
movl TR_V86SIZE+4(%esp),%eax
/* Stash the final register state. */
movl TR_EDI(%esp),%edx; movl %edx,RCD_EDI(%eax)
movl TR_ESI(%esp),%edx; movl %edx,RCD_ESI(%eax)
movl TR_EBP(%esp),%edx; movl %edx,RCD_EBP(%eax)
movl TR_EBX(%esp),%edx; movl %edx,RCD_EBX(%eax)
movl TR_EDX(%esp),%edx; movl %edx,RCD_EDX(%eax)
movl TR_ECX(%esp),%edx; movl %edx,RCD_ECX(%eax)
movl TR_EAX(%esp),%edx; movl %edx,RCD_EAX(%eax)
movl TR_EFLAGS(%esp),%edx; movw %dx,RCD_FLAGS(%eax)
movl TR_V86_ES(%esp),%edx; movw %dx,RCD_ES(%eax)
movl TR_V86_DS(%esp),%edx; movw %dx,RCD_DS(%eax)
movl TR_V86_FS(%esp),%edx; movw %dx,RCD_FS(%eax)
movl TR_V86_GS(%esp),%edx; movw %dx,RCD_GS(%eax)
/* Return from the call to rv86_real_int_asm. */
lea TR_V86SIZE(%esp),%esp
ret
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