coreboot-kgpe-d16/src/include/pc80/i8254.h

64 lines
1.7 KiB
C

/*
* This file is part of the coreboot project.
*
* Copyright (C) 2009 coresystems GmbH
*
* 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; version 2 of the License.
*
* 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.
*/
#ifndef PC80_I8254_H
#define PC80_I8254_H
/* Ports for the 8254 timer chip */
#define TIMER0_PORT 0x40
#define TIMER1_PORT 0x41
#define TIMER2_PORT 0x42
#define TIMER_MODE_PORT 0x43
/* Meaning of the mode bits */
#define TIMER0_SEL 0x00
#define TIMER1_SEL 0x40
#define TIMER2_SEL 0x80
#define READBACK_SEL 0xC0
#define LATCH_COUNT 0x00
#define LOBYTE_ACCESS 0x10
#define HIBYTE_ACCESS 0x20
#define WORD_ACCESS 0x30
#define MODE0 0x00
#define MODE1 0x02
#define MODE2 0x04
#define MODE3 0x06
#define MODE4 0x08
#define MODE5 0x0A
#define BINARY_COUNT 0x00
#define BCD_COUNT 0x01
/* Timers tick over at this rate */
#define TICKS_PER_MS 1193
/* Parallel Peripheral Controller Port B */
#define PPC_PORTB 0x61
/* Meaning of the port bits */
#define PPCB_T2OUT 0x20 /* Bit 5 */
#define PPCB_SPKR 0x02 /* Bit 1 */
#define PPCB_T2GATE 0x01 /* Bit 0 */
void setup_i8254(void);
#endif /* PC80_I8254_H */