2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (C) 2005 TAKAHASHI Yoshihiro. All rights reserved.
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * The outputs of the three timers are connected as follows:
34 * timer 1 -> dma chan 0 (for dram refresh)
35 * timer 2 -> speaker (via keyboard controller)
37 * Timer 0 is used to call hardclock.
38 * Timer 2 is used to generate console beeps.
41 #ifndef _MACHINE_TIMERREG_H_
42 #define _MACHINE_TIMERREG_H_
46 #include <dev/ic/i8253reg.h>
48 #define IO_TIMER1 0x40 /* 8253 Timer #1 */
49 #define TIMER_CNTR0 (IO_TIMER1 + TIMER_REG_CNTR0)
50 #define TIMER_CNTR1 (IO_TIMER1 + TIMER_REG_CNTR1)
51 #define TIMER_CNTR2 (IO_TIMER1 + TIMER_REG_CNTR2)
52 #define TIMER_MODE (IO_TIMER1 + TIMER_REG_MODE)
56 #endif /* _MACHINE_TIMERREG_H_ */