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# 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 Unpublished rights reserved under the copyright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.
#
# 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.
#
# $FreeBSD$
#
.code16
.text
#
# Check magic number at the end of the sector 0
#
check_magic:
movw curdevice, %si
shlw %si
movw secsize(%si), %bx
decw %bx
decw %bx
movw iplbuf(%bx), %ax
cmpw $0xaa55, %ax
je magic_ok
movw $1, %ax
ret
magic_ok:
xorw %ax, %ax
ret
#
# Copy partition table from buffer to parttable.
#
setup_partition:
push %cs
pop %es
movw curdevice, %bx
shlw %bx
movw maxpart(%bx), %cx # %cx = max num of partitions
movw partoff(%bx), %di
movw %di, %bx # %bx = offset to partition table
xorw %dx, %dx # %dx = partition number
setup_partition_loop:
push %cx
movw %dx, %si
movb $5, %cl
shlw %cl, %si
addw %bx, %si
movb iplbuf(%si), %al
orb %al, %al
jz unused_partition
addw $iplbuf, %si
movw npartition, %ax
movw %ax, %di
movb $5, %cl
shlw %cl, %di
addw $parttable, %di
movw $32, %cx
rep
movsb
movw %ax, %di
addw $partnum, %di
movb %dl, (%di)
incw npartition
unused_partition:
incw %dx
pop %cx
loop setup_partition_loop
ret
#
# Read IPL and partition table in the current device.
#
.global read_ipl
read_ipl:
movw curdevice, %ax
movw %ax, %si # %si = device number
movw %ax, %di
shlw %di
movw %cs, %ax
movw %ax, %es
movb $6, %ah
movb daua(%si), %al
movw $0x400, %bx
xorw %cx, %cx
xorw %dx, %dx
movw $iplbuf, %bp
int $0x1b
jc read_ipl_error
movw defflagoff(%di), %bx
movb iplbuf(%bx), %al
movb %al, defpartflag
incw %bx
movb iplbuf(%bx), %al
movb %al, defpartnum
movw $0, npartition
call check_magic
orw %ax, %ax
jnz no_magic
call setup_partition
no_magic:
xorw %ax, %ax
read_ipl_error:
xorw %bx, %bx
movw %bx, %es
ret
#
# Restore IPL from the buffer
#
.global write_ipl
write_ipl:
movw curdevice, %ax
movw %ax, %si
movw %ax, %di
shlw %di
# Restore default boot partition info.
movw defflagoff(%di), %bx
movb defpartflag, %al
movb %al, iplbuf(%bx)
incw %bx
movb defpartnum, %al
movb %al, iplbuf(%bx)
movw %cs, %ax
movw %ax, %es
movb $5, %ah
movb daua(%si), %al
movw secsize(%di), %bx
xorw %cx, %cx
xorw %dx, %dx
movw $iplbuf, %bp
int $0x1b
jc write_ipl_error
xorw %ax, %ax
write_ipl_error:
xorw %bx, %bx
movw %bx, %es
ret
#
# Scan HDD devices
#
.global scan_sasi, scan_scsi
# Scan SASI disk
scan_sasi:
# SASI Disk
movw $4, %cx
movw $0x0001, %ax # %ah = unit number, %al = for bit operation
sasi_loop:
movw %si, %di
shlw %di
movw $0x55d, %bx # DISK_EQUIP
call read_biosparam
testb %al, %dl
jz no_sasi_unit
movb $0x80, %dh
addb %ah, %dh # %dh = DA/UA
movb %dh, daua(%si) # Store DA/UA
# Try new sense command
push %ax
push %cx
movb %dh, %al
movb $0x84, %ah
int $0x1b
pop %cx
pop %ax
jc err_newsense
movw %bx, %dx
jmp found_sasi_unit
err_newsense:
movw $0x457, %bx # capacity & sector size of IDE HDD
call read_biosparam
orb %ah, %ah
jz sasi_1
cmpb $1, %ah
jz sasi_2
# SASI #3/#4
movw $512, %dx # XXX
jmp found_sasi_unit
sasi_1:
# SASI #1
testb $0x80, %dl
jz sasi_256
jmp sasi_512
sasi_2:
# SASI #2
testb $0x40, %dl
jz sasi_256
jmp sasi_512
sasi_256:
movw $256, %dx
jmp found_sasi_unit
sasi_512:
movw $512, %dx
found_sasi_unit:
movw %dx, secsize(%di)
incw %si
no_sasi_unit:
incb %ah
shlb %al
loop sasi_loop
ret
#
# Scan SCSI disk
# SI number of disks
# destroyed: %ax, %bx, %cx, %dx
scan_scsi:
movw $8, %cx
movw $0x0001, %ax # %ah = ID number, %al = for bit operation
scsi_loop:
# Check whether drive exist.
movw %si, %di
shlw %di
movw $0x482, %bx # DISK_EQUIPS
call read_biosparam
testb %al, %dl
jz no_scsi_unit
xorw %bx, %bx
movb %ah, %bl
shlw %bx
shlw %bx
addw $0x460, %bx # SCSI parameter block
call read_biosparam
orb %dl, %dl
jz no_scsi_unit
# SCSI harddrive found.
movb $0xa0, %dh
addb %ah, %dh
movb %dh, daua(%si)
# Check sector size.
addw $3, %bx
call read_biosparam
andb $0x30, %dl
cmpb $0x20, %dl
je scsi_1024
cmpb $0x10, %dl
je scsi_512
movw $256, %dx
jmp found_scsi
scsi_1024:
movw $1024, %dx
jmp found_scsi
scsi_512:
movw $512, %dx
found_scsi:
movw %dx, secsize(%di)
incw %si
no_scsi_unit:
incb %ah
shlb %al
loop scsi_loop
ret
.data
.global defpartflag, defpartnum, npartition
defpartflag: .byte 0
defpartnum: .byte 0
npartition: .word 0 # number of partitions
.bss
.global partnum, parttable
iplbuf: .space 0x400 # Read buffer for IPL
partnum: .space 32 # Index of parttable
parttable: .space 1024 # Copy of valid partition table