dump_eax.S revision 1.2 1 /* $NetBSD: dump_eax.S,v 1.2 2008/04/28 20:23:25 martin 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 /* This is useful for debugging - although you may need to
35 * delete some code to fit it in.
36 * %ds:dump_eax_buff must be somewhere it is safe to write 10 bytes.
37 */
38
39 ENTRY(dump_eax)
40 .code16
41 pusha /* saves bottom 16 bits only! */
42 push %es /* allow for %es != %ds */
43 push %ds
44 pop %es
45 movw $dump_eax_buff, %si
46 mov %si, %di
47 movw $8, %cx
48 1: roll $4, %eax
49 push %ax
50 andb $0x0f, %al
51 addb $0x30, %al /* 30..3f - clear AF */
52 #if 1 /* 5 bytes to generate real hex... */
53 daa /* 30..39, 40..45 */
54 addb $0xc0, %al /* f0..f9, 00..05 */
55 adcb $0x40, %al /* 30..39, 41..45 */
56 #endif
57 stosb
58 pop %ax
59 loop 1b
60 movw $0x20, %ax /* space + null */
61 stosw
62 pop %es
63 jmp message_1
64