1/*	$NetBSD: pvcopy.S,v 1.1 2003/04/16 13:24:10 dsl Exp $	*/
2
3/*-
4 * Copyright (c) 2003 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by David Laight.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include <machine/asm.h>
33
34/*
35 * Routines to copy to/from absolute virtual addresses.
36 * Needed because the boot code runs with %ds having a 64k offset
37 * whereas Unix runs with a zero offset.
38 *
39 * These routines are optimised for code space, not execution speed.
40 */
41
42/*
43 * pbzero(void *dst, int cnt)
44 *	zero absolute virtual memory
45 */
46ENTRY(pbzero)
47	.code32
48	push	%edi
49	push	%es
50	mov	12(%esp),%edi
51	mov	16(%esp),%ecx
52
53	mov	$flatdataseg, %ax	/* selector with offset == 0 */
54	mov	%ax, %es
55	xor	%eax,%eax
56
57	cld
58	rep
59	stosb
60
61	pop	%es
62	pop	%edi
63	ret
64
65/*
66 * vpbcopy(const void *src, void *dst, int cnt)
67 *	Copy to absolute virtual address
68 */
69ENTRY(vpbcopy)
70	.code32
71	push	%esi
72	push	%edi
73	push	%es
74	mov	16(%esp),%esi
75	mov	20(%esp),%edi
76	mov	24(%esp),%ecx
77
78	mov	$flatdataseg, %ax	/* selector with offset == 0 */
79	mov	%ax, %es
80	xor	%eax,%eax
81
82	cld
83	rep
84	movsb
85
86	popl	%es
87	popl	%edi
88	popl	%esi
89	ret
90
91/*
92 * pvbcopy(const void *src, void *dst, int cnt)
93 *	Copy from absolute virtual address
94 */
95ENTRY(pvbcopy)
96	.code32
97	push	%esi
98	push	%edi
99	push	%ds
100	mov	16(%esp),%esi
101	mov	20(%esp),%edi
102	mov	24(%esp),%ecx
103
104	mov	$flatdataseg, %ax	/* selector with offset == 0 */
105	mov	%ax, %ds
106	xor	%eax,%eax
107
108	cld
109	rep
110	movsb
111
112	popl	%ds
113	popl	%edi
114	popl	%esi
115	ret
116