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freebsd-dev/sys/i386/include/clock.h

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Redo Kernel NTP PLL support, kernel side. This code is mostly taken from the 1.1 port (which was in turn taken from Dave Mills's kern.tar.Z example). A few significant differences: 1) ntp_gettime() is now a MIB variable rather than a system call. A few fiddles are done in libc to make it behave the same. 2) mono_time does not participate in the PLL adjustments. 3) A new interface has been defined (in <machine/clock.h>) for doing possibly machine-dependent things around the time of the clock update. This is used in Pentium kernels to disable interrupts, set `time', and reset the CPU cycle counter as quickly as possible to avoid jitter in microtime(). Measurements show an apparent resolution of a bit more than 8.14usec, which is reasonable given system-call overhead.
1994-09-18 20:40:01 +00:00
/*
* Kernel interface to machine-dependent clock driver.
* Garrett Wollman, September 1994.
* This file is in the public domain.
Fix Pentium CPU rate diagnosis: - Don't print out meaningless iCOMP numbers, those are for droids. - Use a shorter wait to determine clock rate to avoid deficiencies in DELAY(). - Use a fixed-point representation with 8 bits of fraction to store the rate and rationalize the variable name. It would be possible to use even more fraction if it turns out to be worthwhile (I rather doubt it). The question of source code arrangement remains unaddressed.
1995-11-29 19:57:22 +00:00
*
Make the long-awaited change from $Id$ to $FreeBSD$ This will make a number of things easier in the future, as well as (finally!) avoiding the Id-smashing problem which has plagued developers for so long. Boy, I'm glad we're not using sup anymore. This update would have been insane otherwise.
1997-01-14 07:20:47 +00:00
* $FreeBSD$
Redo Kernel NTP PLL support, kernel side. This code is mostly taken from the 1.1 port (which was in turn taken from Dave Mills's kern.tar.Z example). A few significant differences: 1) ntp_gettime() is now a MIB variable rather than a system call. A few fiddles are done in libc to make it behave the same. 2) mono_time does not participate in the PLL adjustments. 3) A new interface has been defined (in <machine/clock.h>) for doing possibly machine-dependent things around the time of the clock update. This is used in Pentium kernels to disable interrupts, set `time', and reset the CPU cycle counter as quickly as possible to avoid jitter in microtime(). Measurements show an apparent resolution of a bit more than 8.14usec, which is reasonable given system-call overhead.
1994-09-18 20:40:01 +00:00
*/
#ifndef _MACHINE_CLOCK_H_
Declare the full uglyness of the interfaces to the clock driver (except things declared in machine-independent files).
1994-11-05 22:51:17 +00:00
#define _MACHINE_CLOCK_H_
Redo Kernel NTP PLL support, kernel side. This code is mostly taken from the 1.1 port (which was in turn taken from Dave Mills's kern.tar.Z example). A few significant differences: 1) ntp_gettime() is now a MIB variable rather than a system call. A few fiddles are done in libc to make it behave the same. 2) mono_time does not participate in the PLL adjustments. 3) A new interface has been defined (in <machine/clock.h>) for doing possibly machine-dependent things around the time of the clock update. This is used in Pentium kernels to disable interrupts, set `time', and reset the CPU cycle counter as quickly as possible to avoid jitter in microtime(). Measurements show an apparent resolution of a bit more than 8.14usec, which is reasonable given system-call overhead.
1994-09-18 20:40:01 +00:00
Add Pentium Pro CPU detection and special handling. For now, all the optimizations we have for 586s also apply to 686s...this will be fine- tuned in the future as appropriate.
1995-12-24 08:10:52 +00:00
#if defined(I586_CPU) || defined(I686_CPU)
Improved biasing of i586 clock by adjusting for hardclock() latency. I decided to do this for every hardclock() call instead of lazily in microtime(). The lazy method is simpler but has more overhead if microtime() is called a lot. CPU_THISTICKLEN() is now a no-op and should probably go away. Previously it did nothing directly but had the side effect of setting i586_last_tick for CPU_CLOCKUPDATE() and i586_avg_tick for debugging. CPU_CLOCKUPDATE() now uses a better method and i586_avg_tick is too much trouble to maintain. Reduced nesting of #includes in the usual case. Increased nesting of #includes when CLOCK_HAIR is defined. This is a kludge to get typedefs for inline functions only when the inline functions are used. Normally only kern_clock.c defines this. kern_clock.c can't include the i386 headers directly. Removed unused LOCORE support.
1996-10-25 13:01:56 +00:00
#define CPU_CLOCKUPDATE(otime, ntime) cpu_clockupdate((otime), (ntime))
Redo Kernel NTP PLL support, kernel side. This code is mostly taken from the 1.1 port (which was in turn taken from Dave Mills's kern.tar.Z example). A few significant differences: 1) ntp_gettime() is now a MIB variable rather than a system call. A few fiddles are done in libc to make it behave the same. 2) mono_time does not participate in the PLL adjustments. 3) A new interface has been defined (in <machine/clock.h>) for doing possibly machine-dependent things around the time of the clock update. This is used in Pentium kernels to disable interrupts, set `time', and reset the CPU cycle counter as quickly as possible to avoid jitter in microtime(). Measurements show an apparent resolution of a bit more than 8.14usec, which is reasonable given system-call overhead.
1994-09-18 20:40:01 +00:00
#else
Improved biasing of i586 clock by adjusting for hardclock() latency. I decided to do this for every hardclock() call instead of lazily in microtime(). The lazy method is simpler but has more overhead if microtime() is called a lot. CPU_THISTICKLEN() is now a no-op and should probably go away. Previously it did nothing directly but had the side effect of setting i586_last_tick for CPU_CLOCKUPDATE() and i586_avg_tick for debugging. CPU_CLOCKUPDATE() now uses a better method and i586_avg_tick is too much trouble to maintain. Reduced nesting of #includes in the usual case. Increased nesting of #includes when CLOCK_HAIR is defined. This is a kludge to get typedefs for inline functions only when the inline functions are used. Normally only kern_clock.c defines this. kern_clock.c can't include the i386 headers directly. Removed unused LOCORE support.
1996-10-25 13:01:56 +00:00
#define CPU_CLOCKUPDATE(otime, ntime) (*(otime) = *(ntime))
Redo Kernel NTP PLL support, kernel side. This code is mostly taken from the 1.1 port (which was in turn taken from Dave Mills's kern.tar.Z example). A few significant differences: 1) ntp_gettime() is now a MIB variable rather than a system call. A few fiddles are done in libc to make it behave the same. 2) mono_time does not participate in the PLL adjustments. 3) A new interface has been defined (in <machine/clock.h>) for doing possibly machine-dependent things around the time of the clock update. This is used in Pentium kernels to disable interrupts, set `time', and reset the CPU cycle counter as quickly as possible to avoid jitter in microtime(). Measurements show an apparent resolution of a bit more than 8.14usec, which is reasonable given system-call overhead.
1994-09-18 20:40:01 +00:00
#endif
Improved biasing of i586 clock by adjusting for hardclock() latency. I decided to do this for every hardclock() call instead of lazily in microtime(). The lazy method is simpler but has more overhead if microtime() is called a lot. CPU_THISTICKLEN() is now a no-op and should probably go away. Previously it did nothing directly but had the side effect of setting i586_last_tick for CPU_CLOCKUPDATE() and i586_avg_tick for debugging. CPU_CLOCKUPDATE() now uses a better method and i586_avg_tick is too much trouble to maintain. Reduced nesting of #includes in the usual case. Increased nesting of #includes when CLOCK_HAIR is defined. This is a kludge to get typedefs for inline functions only when the inline functions are used. Normally only kern_clock.c defines this. kern_clock.c can't include the i386 headers directly. Removed unused LOCORE support.
1996-10-25 13:01:56 +00:00
#define CPU_THISTICKLEN(dflt) dflt
Fixed the machdep.i8254_freq and machdep.i586_freq sysctls. Writes were handled bogusly. Centralized the setting of all the frequency variables. Set these variables atomically. Some new ones aren't used yet.
1996-07-30 19:26:55 +00:00
#define I586_CTR_COMULTIPLIER_SHIFT 20
#define I586_CTR_MULTIPLIER_SHIFT 32
Fix Pentium CPU rate diagnosis: - Don't print out meaningless iCOMP numbers, those are for droids. - Use a shorter wait to determine clock rate to avoid deficiencies in DELAY(). - Use a fixed-point representation with 8 bits of fraction to store the rate and rationalize the variable name. It would be possible to use even more fraction if it turns out to be worthwhile (I rather doubt it). The question of source code arrangement remains unaddressed.
1995-11-29 19:57:22 +00:00
Improved biasing of i586 clock by adjusting for hardclock() latency. I decided to do this for every hardclock() call instead of lazily in microtime(). The lazy method is simpler but has more overhead if microtime() is called a lot. CPU_THISTICKLEN() is now a no-op and should probably go away. Previously it did nothing directly but had the side effect of setting i586_last_tick for CPU_CLOCKUPDATE() and i586_avg_tick for debugging. CPU_CLOCKUPDATE() now uses a better method and i586_avg_tick is too much trouble to maintain. Reduced nesting of #includes in the usual case. Increased nesting of #includes when CLOCK_HAIR is defined. This is a kludge to get typedefs for inline functions only when the inline functions are used. Normally only kern_clock.c defines this. kern_clock.c can't include the i386 headers directly. Removed unused LOCORE support.
1996-10-25 13:01:56 +00:00
#ifdef KERNEL
Declare the full uglyness of the interfaces to the clock driver (except things declared in machine-independent files).
1994-11-05 22:51:17 +00:00
/*
* i386 to clock driver interface.
* XXX almost all of it is misplaced. i586 stuff is done in isa/clock.c
* and isa stuff is done in i386/microtime.s and i386/support.s.
*/
extern int adjkerntz;
extern int disable_rtc_set;
Add Pentium Pro CPU detection and special handling. For now, all the optimizations we have for 586s also apply to 686s...this will be fine- tuned in the future as appropriate.
1995-12-24 08:10:52 +00:00
#if defined(I586_CPU) || defined(I686_CPU)
Eliminated i586_ctr_rate. Use i586_ctr_freq instead. Changed i586_ctr_bias from long long to u_int. Only the low 32 bits are used now that microtime uses a multiplication to do the scaling. Previously the high 32 bits had to match those of rdtsc() to prevent overflow traps and invalid timeval adjustments.
1996-08-02 21:16:13 +00:00
extern u_int i586_ctr_bias;
Fixed the machdep.i8254_freq and machdep.i586_freq sysctls. Writes were handled bogusly. Centralized the setting of all the frequency variables. Set these variables atomically. Some new ones aren't used yet.
1996-07-30 19:26:55 +00:00
extern u_int i586_ctr_comultiplier;
extern u_int i586_ctr_freq;
extern u_int i586_ctr_multiplier;
Declare the full uglyness of the interfaces to the clock driver (except things declared in machine-independent files).
1994-11-05 22:51:17 +00:00
#endif
Added missing extern declaration of timer_freq. Sorted declarations of scalars.
1996-10-17 17:31:25 +00:00
extern int statclock_disable;
extern u_int timer_freq;
extern int timer0_max_count;
extern u_int timer0_overflow_threshold;
extern u_int timer0_prescaler_count;
extern int wall_cmos_clock;
Declare the full uglyness of the interfaces to the clock driver (except things declared in machine-independent files).
1994-11-05 22:51:17 +00:00
/*
* Driver to clock driver interface.
*/
Improved biasing of i586 clock by adjusting for hardclock() latency. I decided to do this for every hardclock() call instead of lazily in microtime(). The lazy method is simpler but has more overhead if microtime() is called a lot. CPU_THISTICKLEN() is now a no-op and should probably go away. Previously it did nothing directly but had the side effect of setting i586_last_tick for CPU_CLOCKUPDATE() and i586_avg_tick for debugging. CPU_CLOCKUPDATE() now uses a better method and i586_avg_tick is too much trouble to maintain. Reduced nesting of #includes in the usual case. Increased nesting of #includes when CLOCK_HAIR is defined. This is a kludge to get typedefs for inline functions only when the inline functions are used. Normally only kern_clock.c defines this. kern_clock.c can't include the i386 headers directly. Removed unused LOCORE support.
1996-10-25 13:01:56 +00:00
struct clockframe;
Declare the full uglyness of the interfaces to the clock driver (except things declared in machine-independent files).
1994-11-05 22:51:17 +00:00
void DELAY __P((int usec));
int acquire_timer0 __P((int rate,
void (*function)(struct clockframe *frame)));
int acquire_timer2 __P((int mode));
int release_timer0 __P((void));
int release_timer2 __P((void));
The Great PC98 Merge. All new code is "#ifdef PC98"ed so this should make no difference to PC/AT (and its clones) users. Ok'd by: core Submitted by: FreeBSD(98) development team
1996-06-14 11:02:28 +00:00
#ifndef PC98
Moved rtcin() to clock.c. Always delay using one inb(0x84) after each i/o in rtcin() - don't do this conditional on the bogus option DUMMY_NOPS not being defined. If you want an optionally slightly faster rtcin() again, then inline it and use a better named option or sysctl variable. It only needs to be fast in rtcintr().
1996-03-31 04:05:36 +00:00
int rtcin __P((int val));
The Great PC98 Merge. All new code is "#ifdef PC98"ed so this should make no difference to PC/AT (and its clones) users. Ok'd by: core Submitted by: FreeBSD(98) development team
1996-06-14 11:02:28 +00:00
#else
int acquire_timer1 __P((int mode));
int release_timer1 __P((void));
#endif
Declare the full uglyness of the interfaces to the clock driver (except things declared in machine-independent files).
1994-11-05 22:51:17 +00:00
int sysbeep __P((int pitch, int period));
Improved biasing of i586 clock by adjusting for hardclock() latency. I decided to do this for every hardclock() call instead of lazily in microtime(). The lazy method is simpler but has more overhead if microtime() is called a lot. CPU_THISTICKLEN() is now a no-op and should probably go away. Previously it did nothing directly but had the side effect of setting i586_last_tick for CPU_CLOCKUPDATE() and i586_avg_tick for debugging. CPU_CLOCKUPDATE() now uses a better method and i586_avg_tick is too much trouble to maintain. Reduced nesting of #includes in the usual case. Increased nesting of #includes when CLOCK_HAIR is defined. This is a kludge to get typedefs for inline functions only when the inline functions are used. Normally only kern_clock.c defines this. kern_clock.c can't include the i386 headers directly. Removed unused LOCORE support.
1996-10-25 13:01:56 +00:00
#ifdef CLOCK_HAIR
More merge and update. (1) deleted #if 0 pc98/pc98/mse.c (2) hold per-unit I/O ports in ed_softc pc98/pc98/if_ed.c pc98/pc98/if_ed98.h (3) merge more files by segregating changes into headers. new file (moved from pc98/pc98): i386/isa/aic_98.h deleted: well, it's already in the commit message so I won't repeat the long list here ;) Submitted by: The FreeBSD(98) Development Team
1996-10-30 22:41:46 +00:00
#ifdef PC98
#include <pc98/pc98/pc98.h> /* XXX */
#else
Improved biasing of i586 clock by adjusting for hardclock() latency. I decided to do this for every hardclock() call instead of lazily in microtime(). The lazy method is simpler but has more overhead if microtime() is called a lot. CPU_THISTICKLEN() is now a no-op and should probably go away. Previously it did nothing directly but had the side effect of setting i586_last_tick for CPU_CLOCKUPDATE() and i586_avg_tick for debugging. CPU_CLOCKUPDATE() now uses a better method and i586_avg_tick is too much trouble to maintain. Reduced nesting of #includes in the usual case. Increased nesting of #includes when CLOCK_HAIR is defined. This is a kludge to get typedefs for inline functions only when the inline functions are used. Normally only kern_clock.c defines this. kern_clock.c can't include the i386 headers directly. Removed unused LOCORE support.
1996-10-25 13:01:56 +00:00
#include <i386/isa/isa.h> /* XXX */
More merge and update. (1) deleted #if 0 pc98/pc98/mse.c (2) hold per-unit I/O ports in ed_softc pc98/pc98/if_ed.c pc98/pc98/if_ed98.h (3) merge more files by segregating changes into headers. new file (moved from pc98/pc98): i386/isa/aic_98.h deleted: well, it's already in the commit message so I won't repeat the long list here ;) Submitted by: The FreeBSD(98) Development Team
1996-10-30 22:41:46 +00:00
#endif
Improved biasing of i586 clock by adjusting for hardclock() latency. I decided to do this for every hardclock() call instead of lazily in microtime(). The lazy method is simpler but has more overhead if microtime() is called a lot. CPU_THISTICKLEN() is now a no-op and should probably go away. Previously it did nothing directly but had the side effect of setting i586_last_tick for CPU_CLOCKUPDATE() and i586_avg_tick for debugging. CPU_CLOCKUPDATE() now uses a better method and i586_avg_tick is too much trouble to maintain. Reduced nesting of #includes in the usual case. Increased nesting of #includes when CLOCK_HAIR is defined. This is a kludge to get typedefs for inline functions only when the inline functions are used. Normally only kern_clock.c defines this. kern_clock.c can't include the i386 headers directly. Removed unused LOCORE support.
1996-10-25 13:01:56 +00:00
#include <i386/isa/timerreg.h> /* XXX */
static __inline u_int
clock_latency(void)
{
u_char high, low;
outb(TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
low = inb(TIMER_CNTR0);
high = inb(TIMER_CNTR0);
return (timer0_prescaler_count + timer0_max_count
- ((high << 8) | low));
}
#if defined(I586_CPU) || defined(I686_CPU)
/*
* When we update `time', on i586's we also update `i586_ctr_bias'
* atomically. `i586_ctr_bias' is the best available approximation to
* the value of the i586 counter (mod 2^32) at the time of the i8254
* counter transition that caused the clock interrupt that caused the
* update. clock_latency() gives the time between the transition and
* the update to within a few usec provided another such transition
* hasn't occurred. We don't bother checking for counter overflow as
* in microtime(), since if it occurs then we're close to losing clock
* interrupts.
*/
static __inline void
cpu_clockupdate(volatile struct timeval *otime, struct timeval *ntime)
{
if (i586_ctr_freq != 0) {
u_int i586_count; /* truncated */
u_int i8254_count;
disable_intr();
i8254_count = clock_latency();
i586_count = rdtsc();
i586_ctr_bias = i586_count
- (u_int)
(((unsigned long long)i586_ctr_comultiplier
* i8254_count)
>> I586_CTR_COMULTIPLIER_SHIFT);
*otime = *ntime;
enable_intr();
} else
*otime = *ntime;
}
#endif /* I586_CPU || I686_CPU */
#endif /* CLOCK_HAIR */
#endif /* KERNEL */
Declare the full uglyness of the interfaces to the clock driver (except things declared in machine-independent files).
1994-11-05 22:51:17 +00:00
#endif /* !_MACHINE_CLOCK_H_ */
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