clock.h revision 15045 
1/*
2 * Kernel interface to machine-dependent clock driver.
3 * Garrett Wollman, September 1994.
4 * This file is in the public domain.
5 *
6 *	$Id: clock.h,v 1.10 1996/03/31 04:05:17 bde Exp $
7 */
8
9#ifndef _MACHINE_CLOCK_H_
10#define	_MACHINE_CLOCK_H_
11
12#if defined(I586_CPU) || defined(I686_CPU)
13
14#define I586_CYCLECTR(x) \
15	__asm __volatile(".byte 0x0f, 0x31" : "=A" (x))
16
17/*
18 * When we update the clock, we also update this bias value which is
19 * automatically subtracted in microtime().  We assume that CPU_THISTICKLEN()
20 * has been called at some point in the past, so that an appropriate value is
21 * set up in i586_last_tick.  (This works even if we are not being called
22 * from hardclock because hardclock will have run before and will made the
23 * call.)
24 */
25#define CPU_CLOCKUPDATE(otime, ntime) \
26	do { \
27	if(i586_ctr_rate) { \
28		disable_intr(); \
29		i586_ctr_bias = i586_last_tick; \
30		*(otime) = *(ntime); \
31		enable_intr(); \
32	} else { \
33		*(otime) = *(ntime); \
34	} \
35	} while(0)
36
37#define	CPU_THISTICKLEN(dflt) cpu_thisticklen(dflt)
38#else
39#define CPU_CLOCKUPDATE(otime, ntime) \
40		(*(otime) = *(ntime))
41#define CPU_THISTICKLEN(dflt) dflt
42#endif
43
44#define		I586_CTR_RATE_SHIFT	8
45
46#if defined(KERNEL) && !defined(LOCORE)
47#include <sys/cdefs.h>
48#include <machine/frame.h>
49
50/*
51 * i386 to clock driver interface.
52 * XXX almost all of it is misplaced.  i586 stuff is done in isa/clock.c
53 * and isa stuff is done in i386/microtime.s and i386/support.s.
54 */
55extern int	adjkerntz;
56extern int	disable_rtc_set;
57extern int	wall_cmos_clock;
58
59#if defined(I586_CPU) || defined(I686_CPU)
60extern unsigned	i586_ctr_rate;	/* fixed point */
61extern long long i586_last_tick;
62extern long long i586_ctr_bias;
63extern unsigned long i586_avg_tick;
64#endif
65extern int 	timer0_max_count;
66extern u_int 	timer0_overflow_threshold;
67extern u_int 	timer0_prescaler_count;
68
69#if defined(I586_CPU) || defined(I686_CPU)
70void	calibrate_cyclecounter __P((void));
71#endif
72
73#if defined(I586_CPU) || defined(I686_CPU)
74static __inline u_long
75cpu_thisticklen(u_long dflt)
76{
77	long long old;
78	long len;
79
80	if (i586_ctr_rate) {
81		old = i586_last_tick;
82		I586_CYCLECTR(i586_last_tick);
83		len = ((i586_last_tick - old) << I586_CTR_RATE_SHIFT)
84			/ i586_ctr_rate;
85		i586_avg_tick = i586_avg_tick * 15 / 16 + len / 16;
86	}
87	return dflt;
88}
89#endif
90
91/*
92 * Driver to clock driver interface.
93 */
94void	DELAY __P((int usec));
95int	acquire_timer0 __P((int rate,
96			    void (*function)(struct clockframe *frame)));
97int	acquire_timer2 __P((int mode));
98int	release_timer0 __P((void));
99int	release_timer2 __P((void));
100int	rtcin __P((int val));
101int	sysbeep __P((int pitch, int period));
102
103#endif /* KERNEL && !LOCORE */
104
105#endif /* !_MACHINE_CLOCK_H_ */
106