minix/sys/arch/i386/stand/lib/pvcopy.S
2012-02-09 18:48:13 +01:00

115 lines
2.7 KiB
ArmAsm

/* $NetBSD: pvcopy.S,v 1.2 2008/04/28 20:23:25 martin Exp $ */
/*-
* Copyright (c) 2003 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by David Laight.
*
* 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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 <machine/asm.h>
/*
* Routines to copy to/from absolute virtual addresses.
* Needed because the boot code runs with %ds having a 64k offset
* whereas Unix runs with a zero offset.
*
* These routines are optimised for code space, not execution speed.
*/
/*
* pbzero(void *dst, int cnt)
* zero absolute virtual memory
*/
ENTRY(pbzero)
.code32
push %edi
push %es
mov 12(%esp),%edi
mov 16(%esp),%ecx
mov $flatdataseg, %ax /* selector with offset == 0 */
mov %ax, %es
xor %eax,%eax
cld
rep
stosb
pop %es
pop %edi
ret
/*
* vpbcopy(const void *src, void *dst, int cnt)
* Copy to absolute virtual address
*/
ENTRY(vpbcopy)
.code32
push %esi
push %edi
push %es
mov 16(%esp),%esi
mov 20(%esp),%edi
mov 24(%esp),%ecx
mov $flatdataseg, %ax /* selector with offset == 0 */
mov %ax, %es
xor %eax,%eax
cld
rep
movsb
popl %es
popl %edi
popl %esi
ret
/*
* pvbcopy(const void *src, void *dst, int cnt)
* Copy from absolute virtual address
*/
ENTRY(pvbcopy)
.code32
push %esi
push %edi
push %ds
mov 16(%esp),%esi
mov 20(%esp),%edi
mov 24(%esp),%ecx
mov $flatdataseg, %ax /* selector with offset == 0 */
mov %ax, %ds
xor %eax,%eax
cld
rep
movsb
popl %ds
popl %edi
popl %esi
ret