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Diffstat (limited to 'arch/x86/lib/pcat_timer.c')
-rw-r--r-- | arch/x86/lib/pcat_timer.c | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/arch/x86/lib/pcat_timer.c b/arch/x86/lib/pcat_timer.c new file mode 100644 index 0000000..1ca3eb9 --- /dev/null +++ b/arch/x86/lib/pcat_timer.c @@ -0,0 +1,43 @@ +/* + * (C) Copyright 2002 + * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se> + * + * See file CREDITS for list of people who contributed to this + * project. + * + * 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 + */ + +#include <common.h> +#include <asm/io.h> +#include <asm/i8254.h> + +#define TIMER2_VALUE 0x0a8e /* 440Hz */ + +int pcat_timer_init(void) +{ + /* + * initialize 2, used to drive the speaker + * (to start a beep: write 3 to port 0x61, + * to stop it again: write 0) + */ + outb(PIT_CMD_CTR2 | PIT_CMD_BOTH | PIT_CMD_MODE3, + PIT_BASE + PIT_COMMAND); + outb(TIMER2_VALUE & 0xff, PIT_BASE + PIT_T2); + outb(TIMER2_VALUE >> 8, PIT_BASE + PIT_T2); + + return 0; +} |