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 39ENTRY(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 481: 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