/* Defines for routines to implement a low-overhead timer for drivers */

 /*
 * 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, or (at
 * your option) any later version.
 */

#ifndef TIMER_H
#define TIMER_H

/* Ports for the 8254 timer chip */
#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 CLOCK_TICK_RATE 1193180U
#define TICKS_PER_MS    (CLOCK_TICK_RATE/1000)

/* 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 */

/* Ticks must be between 0 and 65535 (0 == 65536)
   because it is a 16 bit counter */
extern void load_timer2(unsigned int ticks);
extern inline int timer2_running(void);
extern void waiton_timer2(unsigned int ticks);
extern void __load_timer2(unsigned int ticks);

extern void setup_timers(void);
extern void ndelay(unsigned int nsecs);
extern void udelay(unsigned int usecs);
extern void mdelay(unsigned int msecs);
//extern unsigned long currticks(void);

struct timeval {
        long tv_sec;
        long tv_usec;
};

#endif  /* TIMER_H */