78 lines
2.1 KiB
ArmAsm
78 lines
2.1 KiB
ArmAsm
/*
|
|
* Copyright (C) 2009 Juergen Beisert, Pengutronix
|
|
*
|
|
* Mostly stolen from the GRUB2 project
|
|
* Copyright (C) 1999,2000,2001,2002,2003,2004,2005,2006,2007,2008 Free Software Foundation, Inc.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License as
|
|
* published by the Free Software Foundation; either version 2 of
|
|
* the License, or (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
|
|
* MA 02111-1307 USA
|
|
*
|
|
*/
|
|
|
|
/**
|
|
* @file
|
|
* @brief Do BIOS calls to load or save data from disks
|
|
*
|
|
* @note These functions are running in flat and real mode. Due to some
|
|
* other restrictions these routines must running from an address
|
|
* space below 0x10000
|
|
*/
|
|
|
|
#ifndef DOXYGEN_SHOULD_SKIP_THIS
|
|
/*
|
|
* int bios_disk_rw_int13_extensions (int ah, int drive, void *dap)
|
|
*
|
|
* Call IBM/MS INT13 Extensions (int 13 %ah=AH) for DRIVE. DAP
|
|
* is passed for disk address packet. If an error occurs, return
|
|
* non-zero, otherwise zero.
|
|
*/
|
|
.section .boot.text.bios_disk_rw_int13_extensions, "ax"
|
|
.code32
|
|
.globl bios_disk_rw_int13_extensions
|
|
.type bios_disk_rw_int13_extensions, @function
|
|
|
|
.extern prot_to_real
|
|
.extern real_to_prot
|
|
|
|
bios_disk_rw_int13_extensions:
|
|
pushl %ebp
|
|
pushl %esi
|
|
|
|
/* compute the address of disk_address_packet */
|
|
movw %cx, %si
|
|
xorw %cx, %cx
|
|
shrl $4, %ecx /* save the segment to cx */
|
|
|
|
movb %al, %dh
|
|
call prot_to_real /* enter real mode right now */
|
|
|
|
.code16
|
|
movb %dh, %ah
|
|
movw %cx, %ds
|
|
int $0x13 /* do the operation */
|
|
movb %ah, %dl /* save return value */
|
|
/* back to protected mode */
|
|
DATA32 call real_to_prot
|
|
|
|
.code32
|
|
movb %dl, %al /* return value in %eax */
|
|
|
|
popl %esi
|
|
popl %ebp
|
|
|
|
ret
|
|
|
|
#endif
|