blob: 7c9bec4dbebe2c36a3ea5fc8dc3475bedd467068 (
plain) (
tree)
|
|
/*
* Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <realmode.h>
#include <console.h>
/**
* Print a character to BIOS console
*
* @v character Character to be printed
*/
static void bios_putchar ( int character ) {
__asm__ __volatile__ ( REAL_CODE ( "sti\n\t"
"int $0x10\n\t"
"cli\n\t" )
: : "a" ( character | 0x0e00 ), "b" ( 1 )
: "ebp" );
}
/**
* Get character from BIOS console
*
* @ret character Character read from console
*/
static int bios_getchar ( void ) {
uint8_t character;
__asm__ __volatile__ ( REAL_CODE ( "sti\n\t"
"int $0x16\n\t"
"cli\n\t" )
: "=a" ( character ) : "a" ( 0x0000 ) );
return character;
}
/**
* Check for character ready to read from BIOS console
*
* @ret True Character available to read
* @ret False No character available to read
*/
static int bios_iskey ( void ) {
unsigned int discard_a;
unsigned int flags;
__asm__ __volatile__ ( REAL_CODE ( "sti\n\t"
"int $0x16\n\t"
"pushfw\n\t"
"popw %w0\n\t"
"cli\n\t" )
: "=r" ( flags ), "=a" ( discard_a )
: "a" ( 0x0100 ) );
return ( ! ( flags & ZF ) );
}
struct console_driver bios_console __console_driver = {
.putchar = bios_putchar,
.getchar = bios_getchar,
.iskey = bios_iskey,
};
|
