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ipxe/src/arch/i386/interface/pcbios/apm.c

113 lines
3.3 KiB
C

/*
* Copyright (C) 2013 Marin Hannache <ipxe@mareo.fr>.
*
* 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 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., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*
* You can also choose to distribute this program under the terms of
* the Unmodified Binary Distribution Licence (as given in the file
* COPYING.UBDL), provided that you have satisfied its requirements.
*/
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
/**
* @file
*
* Advanced Power Management
*
*/
#include <errno.h>
#include <realmode.h>
#include <ipxe/reboot.h>
/**
* Power off the computer using APM
*
* @ret rc Return status code
*/
static int apm_poweroff ( void ) {
uint16_t apm_version;
uint16_t apm_signature;
uint16_t apm_flags;
uint16_t carry;
/* APM check */
__asm__ __volatile__ ( REAL_CODE ( "int $0x15\n\t"
"adc %%edx,0\n\t" )
: "=a" ( apm_version ), "=b" ( apm_signature ),
"=c" ( apm_flags ), "=d" ( carry )
: "a" ( 0x5300 ), "b" ( 0x0000 ),
"d" ( 0x0000 ) );
if ( carry ) {
DBG ( "APM not present\n" );
return -ENOTSUP;
}
if ( apm_signature != 0x504d ) { /* signature 'PM' */
DBG ( "APM not present\n" );
return -ENOTSUP;
}
if ( apm_version < 0x0101 ) { /* Need version 1.1+ */
DBG ( "APM 1.1+ not supported\n" );
return -ENOTSUP;
}
if ( ( apm_flags & 0x8 ) == 0x8 ) {
DBG ( "APM power management disabled\n" );
return -EPERM;
}
DBG2 ( "APM check completed\n" );
/* APM initialisation */
__asm__ __volatile__ ( REAL_CODE ( "int $0x15\n\t"
"adc %%edx,0\n\t" )
: "=d" ( carry )
: "a" ( 0x5301 ), "b" ( 0x0000 ),
"d" ( 0x0000 ) );
if ( carry ) {
DBG ( "APM initialisation failed\n" );
return -EIO;
}
DBG2 ( "APM initialisation completed\n" );
/* Set APM driver version */
__asm__ __volatile__ ( REAL_CODE ( "int $0x15\n\t"
"adc %%edx,0\n\t" )
: "=d" ( carry )
: "a" ( 0x530e ), "b" ( 0x0000 ),
"c" ( 0x0101 ), "d" ( 0x0000 ) );
if ( carry ) {
DBG ( "APM setting driver version failed\n" );
return -EIO;
}
DBG2 ( "APM driver version set\n" );
/* Setting power state to off */
__asm__ __volatile__ ( REAL_CODE ( "int $0x15\n\t"
"adc %%edx,0\n\t" )
: "=d" ( carry )
: "a" ( 0x5307 ), "b" ( 0x0001 ),
"c" ( 0x0003 ), "d" ( 0x0000) );
if ( carry ) {
DBG ( "APM setting power state failed\n" );
return -ENOTTY;
}
/* Should never happen */
return -ECANCELED;
}
PROVIDE_REBOOT ( pcbios, poweroff, apm_poweroff );