diff options
Diffstat (limited to 'stand/i386/btx/lib/btxv86.s')
-rw-r--r-- | stand/i386/btx/lib/btxv86.s | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/stand/i386/btx/lib/btxv86.s b/stand/i386/btx/lib/btxv86.s new file mode 100644 index 0000000000000..0d7d1116322d2 --- /dev/null +++ b/stand/i386/btx/lib/btxv86.s @@ -0,0 +1,85 @@ +# +# Copyright (c) 1998 Robert Nordier +# All rights reserved. +# +# Redistribution and use in source and binary forms are freely +# permitted provided that the above copyright notice and this +# paragraph and the following disclaimer are duplicated in all +# such forms. +# +# This software is provided "AS IS" and without any express or +# implied warranties, including, without limitation, the implied +# warranties of merchantability and fitness for a particular +# purpose. +# + +# $FreeBSD$ + +# +# BTX V86 interface. +# + +# +# Globals. +# + .global __v86int +# +# Fields in V86 interface structure. +# + .set V86_CTL,0x0 # Control flags + .set V86_ADDR,0x4 # Int number/address + .set V86_ES,0x8 # V86 ES + .set V86_DS,0xc # V86 DS + .set V86_FS,0x10 # V86 FS + .set V86_GS,0x14 # V86 GS + .set V86_EAX,0x18 # V86 EAX + .set V86_ECX,0x1c # V86 ECX + .set V86_EDX,0x20 # V86 EDX + .set V86_EBX,0x24 # V86 EBX + .set V86_EFL,0x28 # V86 eflags + .set V86_EBP,0x2c # V86 EBP + .set V86_ESI,0x30 # V86 ESI + .set V86_EDI,0x34 # V86 EDI +# +# Other constants. +# + .set INT_V86,0x31 # Interrupt number + .set SIZ_V86,0x38 # Size of V86 structure +# +# V86 interface function. +# +__v86int: popl __v86ret # Save return address + pushl $__v86 # Push pointer + call __v86_swap # Load V86 registers + int $INT_V86 # To BTX + call __v86_swap # Load user registers + addl $0x4,%esp # Discard pointer + pushl __v86ret # Restore return address + ret # To user +# +# Swap V86 and user registers. +# +__v86_swap: xchgl %ebp,0x4(%esp,1) # Swap pointer, EBP + xchgl %eax,V86_EAX(%ebp) # Swap EAX + xchgl %ecx,V86_ECX(%ebp) # Swap ECX + xchgl %edx,V86_EDX(%ebp) # Swap EDX + xchgl %ebx,V86_EBX(%ebp) # Swap EBX + pushl %eax # Save + pushf # Put eflags + popl %eax # in EAX + xchgl %eax,V86_EFL(%ebp) # Swap + pushl %eax # Put EAX + popf # in eflags + movl 0x8(%esp,1),%eax # Load EBP + xchgl %eax,V86_EBP(%ebp) # Swap + movl %eax,0x8(%esp,1) # Save EBP + popl %eax # Restore + xchgl %esi,V86_ESI(%ebp) # Swap ESI + xchgl %edi,V86_EDI(%ebp) # Swap EDI + xchgl %ebp,0x4(%esp,1) # Swap pointer, EBP + ret # To caller +# +# V86 interface structure. +# + .comm __v86,SIZ_V86 + .comm __v86ret,4 |