| Current Path : /usr/src/sys/boot/pc98/boot0.5/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //usr/src/sys/boot/pc98/boot0.5/disk.s |
# 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 Unpublished rights reserved under the copyright # laws of Japan.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: release/9.1.0/sys/boot/pc98/boot0.5/disk.s 167657 2007-03-17 05:30:03Z kato $ # .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 paramter 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