freebsd-skq/sys/boot/pc98/boot0/boot0.s
kato 719b29e2f0 Added PC-98 HDD boot manager. The boot0 is the `IPL' which occupies
sector 0 of a disk and boot0.5 is the `boot selector' which starts
from address 0x400.  The IPL loads boot0.5 and boot0.5 loads bootblock
of a slice.

The boot manager stuff was developed by me (kato) with Borland C++,
and then, translated into bcc in the ports collection by Nokubi-san.
After that, boot0 has been translated into gas with the .code16
directive by Takahashi-san (nyan) and boot0.5 has been rewritten in
gas by me.
2000-08-02 08:46:08 +00:00

109 lines
2.4 KiB
ArmAsm

# Copyright (c) KATO Takenori, 1999, 2000.
#
# All rights reserved. Unpublished rights reserved under the copyright
# laws of Japan.
#
# 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 as
# the first lines of this file unmodified.
# 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.
# 3. The name of the author may not be used to endorse or promote products
# derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
#
# $FreeBSD$
.globl start
.code16
start:
jmp main
.org 4
.ascii "IPL1"
.byte 0, 0, 0
.globl start
main:
xor %ax, %ax
mov %ax, %ds
mov (0x584), %al # DA/UA
mov %al, %ah
and $0xf0, %ah
cmp $0x90, %ah
je fdd
# hdd
mov $6, %ah
mov $0x3000, %bx
mov %bx, %es
mov $0x2000, %bx
xor %cx, %cx
xor %dx, %dx
xor %bp, %bp
int $0x1b
jc error_hdd
push %ax
mov %es, %ax
add $0x40, %ax
mov %ax, %es
pop %ax
push %es
push %bp
lret
# fdd
fdd:
xor %di, %di
fdd_retry:
mov $0xd6, %ah
mov $0x3000, %bx
mov %bx, %es
mov $0x2000, %bx
mov $0x0200, %cx
mov $0x0001, %dx
xor %bp, %bp
int $0x1b
jc error
push %ax
mov %es, %ax
add $0x40, %ax
mov %ax, %es
pop %ax
push %es
push %bp
lret
error:
or %di, %di
jnz error_hdd
and $0x0f, %al
or $0x30, %al
jmp fdd_retry
error_hdd:
jmp error
.org 0x1fa
.byte 0 # defflag_off
.byte 0 # defpart_off
.byte 1 # menu version
.byte 0
.word 0xaa55