freebsd-dev/sys/ia64/include/clock.h
Marcel Moolenaar 46e31b2612 Cleanup the clock code. This includes:
o  Remove alpha specific timer code (mc146818A) and compiled-out
   calibration of said timer.
o  Remove i386 inherited timer code (i8253) and related acquire and
   release functions.
o  Move sysbeep() from clock.c to machdep.c and have it return
   ENODEV. Console beeps should be implemented using ACPI or if no
   such device is described, using the sound driver.
o  Move the sysctls related to adjkerntz, disable_rtc_set and
   wall_cmos_clock from machdep.c to clock.c, where the variables
   are.
o  Don't hardcode a hz value of 1024 in cpu_initclocks() and don't
   bother faking a stathz that's 1/8 of that. Keep it simple: hz
   defaults to HZ and stathz equals hz. This is also how it's done
   for sparc64.
o  Keep a per-CPU ITC counter (pc_clock) and adjustment (pc_clockadj)
   to calculate ITC skew and corrections. On average, we adjust the
   ITC match register once every ~1500 interrupts for a duration of
   2 consequtive interruprs. This is to correct the non-deterministic
   behaviour of the ITC interrupt (there's a delay between the match
   and the raising of the interrupt).
o  Add 4 debugging sysctls to monitor clock behaviour. Those are
   debug.clock_adjust_edges, debug.clock_adjust_excess,
   debug.clock_adjust_lost and debug.clock_adjust_ticks. The first
   counts the individual adjustment cycles (when the skew first
   crosses the threshold), the second counts the number of times the
   adjustment was excessive (any non-zero value is to be considered
   a bug), the third counts lost clock interrupts and the last counts
   the number of interrupts for which we applied an adjustment
   (debug.clock_adjust_ticks / debug.clock_adjust_edges gives the
   avarage duration of an individual adjustment -- should be ~2).

While here, remove some nearby (trivial) left-overs from alpha and
other cleanups.
2003-08-04 05:13:18 +00:00

28 lines
471 B
C

/*
* Kernel interface to machine-dependent clock driver.
* Garrett Wollman, September 1994.
* This file is in the public domain.
*
* $FreeBSD$
*/
#ifndef _MACHINE_CLOCK_H_
#define _MACHINE_CLOCK_H_
#ifdef _KERNEL
#define CLOCK_VECTOR 254
extern int adjkerntz;
extern int disable_rtc_set;
extern int wall_cmos_clock;
extern uint64_t ia64_clock_reload;
extern uint64_t itc_frequency;
int sysbeep(int pitch, int period);
#endif
#endif /* !_MACHINE_CLOCK_H_ */