/*
* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
*
* @APPLE_LICENSE_HEADER_START@
*
* The contents of this file constitute Original Code as defined in and
* are subject to the Apple Public Source License Version 1.1 (the
* "License"). You may not use this file except in compliance with the
* License. Please obtain a copy of the License at
* http://www.apple.com/publicsource and read it before using this file.
*
* This Original Code and all software distributed under the License are
* distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
* License for the specific language governing rights and limitations
* under the License.
*
* @APPLE_LICENSE_HEADER_END@
*/
/*
* @OSF_COPYRIGHT@
*/
/*
* @APPLE_FREE_COPYRIGHT@
*/
/*
* File: rtclock.c
* Purpose: Routines for handling the machine dependent
* real-time clock.
*/
#include <libkern/OSTypes.h>
#include <mach/mach_types.h>
#include <kern/clock.h>
#include <kern/thread.h>
#include <kern/macro_help.h>
#include <kern/spl.h>
#include <machine/mach_param.h> /* HZ */
#include <ppc/proc_reg.h>
#include <pexpert/pexpert.h>
#include <sys/kdebug.h>
int sysclk_config(void);
int sysclk_init(void);
kern_return_t sysclk_gettime(
mach_timespec_t *cur_time);
kern_return_t sysclk_getattr(
clock_flavor_t flavor,
clock_attr_t attr,
mach_msg_type_number_t *count);
void sysclk_setalarm(
mach_timespec_t *deadline);
struct clock_ops sysclk_ops = {
sysclk_config, sysclk_init,
sysclk_gettime, 0,
sysclk_getattr, 0,
sysclk_setalarm,
};
int calend_config(void);
int calend_init(void);
kern_return_t calend_gettime(
mach_timespec_t *cur_time);
kern_return_t calend_settime(
mach_timespec_t *cur_time);
kern_return_t calend_getattr(
clock_flavor_t flavor,
clock_attr_t attr,
mach_msg_type_number_t *count);
struct clock_ops calend_ops = {
calend_config, calend_init,
calend_gettime, calend_settime,
calend_getattr, 0,
0,
};
/* local data declarations */
static struct rtclock {
mach_timespec_t calend_offset;
boolean_t calend_is_set;
mach_timebase_info_data_t timebase_const;
struct rtclock_timer {
uint64_t deadline;
boolean_t is_set;
} timer[NCPUS];
clock_timer_func_t timer_expire;
timer_call_data_t alarm[NCPUS];
/* debugging */
uint64_t last_abstime[NCPUS];
int last_decr[NCPUS];
decl_simple_lock_data(,lock) /* real-time clock device lock */
} rtclock;
static boolean_t rtclock_initialized;
static uint64_t rtclock_tick_deadline[NCPUS];
static uint64_t rtclock_tick_interval;
static void timespec_to_absolutetime(
mach_timespec_t timespec,
uint64_t *result);
static int deadline_to_decrementer(
uint64_t deadline,
uint64_t now);
static void rtclock_alarm_timer(
timer_call_param_t p0,
timer_call_param_t p1);
/* global data declarations */
#define RTC_TICKPERIOD (NSEC_PER_SEC / HZ)
#define DECREMENTER_MAX 0x7FFFFFFFUL
#define DECREMENTER_MIN 0xAUL
natural_t rtclock_decrementer_min;
/*
* Macros to lock/unlock real-time clock device.
*/
#define LOCK_RTC(s) \
MACRO_BEGIN \
(s) = splclock(); \
simple_lock(&rtclock.lock); \
MACRO_END
#define UNLOCK_RTC(s) \
MACRO_BEGIN \
simple_unlock(&rtclock.lock); \
splx(s); \
MACRO_END
static void
timebase_callback(
struct timebase_freq_t *freq)
{
natural_t numer, denom;
int n;
spl_t s;
denom = freq->timebase_num;
n = 9;
while (!(denom % 10)) {
if (n < 1)
break;
denom /= 10;
n--;
}
numer = freq->timebase_den;
while (n-- > 0) {
numer *= 10;
}
LOCK_RTC(s);
rtclock.timebase_const.numer = numer;
rtclock.timebase_const.denom = denom;
UNLOCK_RTC(s);
}
/*
* Configure the real-time clock device.
*/
int
sysclk_config(void)
{
int i;
if (cpu_number() != master_cpu)
return(1);
for (i = 0; i < NCPUS; i++)
timer_call_setup(&rtclock.alarm[i], rtclock_alarm_timer, NULL);
simple_lock_init(&rtclock.lock, ETAP_MISC_RT_CLOCK);
PE_register_timebase_callback(timebase_callback);
return (1);
}
/*
* Initialize the system clock device.
*/
int
sysclk_init(void)
{
uint64_t abstime;
int decr, mycpu = cpu_number();
if (mycpu != master_cpu) {
if (rtclock_initialized == FALSE) {
panic("sysclk_init on cpu %d, rtc not initialized\n", mycpu);
}
/* Set decrementer and hence our next tick due */
clock_get_uptime(&abstime);
rtclock_tick_deadline[mycpu] = abstime;
rtclock_tick_deadline[mycpu] += rtclock_tick_interval;
decr = deadline_to_decrementer(rtclock_tick_deadline[mycpu], abstime);
mtdec(decr);
rtclock.last_decr[mycpu] = decr;
return(1);
}
/*
* Initialize non-zero clock structure values.
*/
clock_interval_to_absolutetime_interval(RTC_TICKPERIOD, 1,
&rtclock_tick_interval);
/* Set decrementer and our next tick due */
clock_get_uptime(&abstime);
rtclock_tick_deadline[mycpu] = abstime;
rtclock_tick_deadline[mycpu] += rtclock_tick_interval;
decr = deadline_to_decrementer(rtclock_tick_deadline[mycpu], abstime);
mtdec(decr);
rtclock.last_decr[mycpu] = decr;
rtclock_initialized = TRUE;
return (1);
}
#define UnsignedWide_to_scalar(x) (*(uint64_t *)(x))
#define scalar_to_UnsignedWide(x) (*(UnsignedWide *)(x))
/*
* Perform a full 64 bit by 32 bit unsigned multiply,
* yielding a 96 bit product. The most significant
* portion of the product is returned as a 64 bit
* quantity, with the lower portion as a 32 bit word.
*/
static void
umul_64by32(
UnsignedWide now64,
uint32_t mult32,
UnsignedWide *result64,
uint32_t *result32)
{
uint32_t mid, mid2;
asm volatile(" mullw %0,%1,%2" :
"=r" (*result32) :
"r" (now64.lo), "r" (mult32));
asm volatile(" mullw %0,%1,%2" :
"=r" (mid2) :
"r" (now64.hi), "r" (mult32));
asm volatile(" mulhwu %0,%1,%2" :
"=r" (mid) :
"r" (now64.lo), "r" (mult32));
asm volatile(" mulhwu %0,%1,%2" :
"=r" (result64->hi) :
"r" (now64.hi), "r" (mult32));
asm volatile(" addc %0,%2,%3;
addze %1,%4" :
"=r" (result64->lo), "=r" (result64->hi) :
"r" (mid), "r" (mid2), "1" (result64->hi));
}
/*
* Perform a partial 64 bit by 32 bit unsigned multiply,
* yielding a 64 bit product. Only the least significant
* 64 bits of the product are calculated and returned.
*/
static void
umul_64by32to64(
UnsignedWide now64,
uint32_t mult32,
UnsignedWide *result64)
{
uint32_t mid, mid2;
asm volatile(" mullw %0,%1,%2" :
"=r" (result64->lo) :
"r" (now64.lo), "r" (mult32));
asm volatile(" mullw %0,%1,%2" :
"=r" (mid2) :
"r" (now64.hi), "r" (mult32));
asm volatile(" mulhwu %0,%1,%2" :
"=r" (mid) :
"r" (now64.lo), "r" (mult32));
asm volatile(" add %0,%1,%2" :
"=r" (result64->hi) :
"r" (mid), "r" (mid2));
}
/*
* Perform an unsigned division of a 96 bit value
* by a 32 bit value, yielding a 96 bit quotient.
* The most significant portion of the product is
* returned as a 64 bit quantity, with the lower
* portion as a 32 bit word.
*/
static void
udiv_96by32(
UnsignedWide now64,
uint32_t now32,
uint32_t div32,
UnsignedWide *result64,
uint32_t *result32)
{
UnsignedWide t64;
if (now64.hi > 0 || now64.lo >= div32) {
UnsignedWide_to_scalar(result64) =
UnsignedWide_to_scalar(&now64) / div32;
umul_64by32to64(*result64, div32, &t64);
UnsignedWide_to_scalar(&t64) =
UnsignedWide_to_scalar(&now64) - UnsignedWide_to_scalar(&t64);
*result32 = (((uint64_t)t64.lo << 32) | now32) / div32;
}
else {
UnsignedWide_to_scalar(result64) =
(((uint64_t)now64.lo << 32) | now32) / div32;
*result32 = result64->lo;
result64->lo = result64->hi;
result64->hi = 0;
}
}
/*
* Perform an unsigned division of a 96 bit value
* by a 32 bit value, yielding a 64 bit quotient.
* Any higher order bits of the quotient are simply
* discarded.
*/
static void
udiv_96by32to64(
UnsignedWide now64,
uint32_t now32,
uint32_t div32,
UnsignedWide *result64)
{
UnsignedWide t64;
if (now64.hi > 0 || now64.lo >= div32) {
UnsignedWide_to_scalar(result64) =
UnsignedWide_to_scalar(&now64) / div32;
umul_64by32to64(*result64, div32, &t64);
UnsignedWide_to_scalar(&t64) =
UnsignedWide_to_scalar(&now64) - UnsignedWide_to_scalar(&t64);
result64->hi = result64->lo;
result64->lo = (((uint64_t)t64.lo << 32) | now32) / div32;
}
else {
UnsignedWide_to_scalar(result64) =
(((uint64_t)now64.lo << 32) | now32) / div32;
}
}
/*
* Perform an unsigned division of a 96 bit value
* by a 32 bit value, yielding a 32 bit quotient,
* and a 32 bit remainder. Any higher order bits
* of the quotient are simply discarded.
*/
static void
udiv_96by32to32and32(
UnsignedWide now64,
uint32_t now32,
uint32_t div32,
uint32_t *result32,
uint32_t *remain32)
{
UnsignedWide t64, u64;
if (now64.hi > 0 || now64.lo >= div32) {
UnsignedWide_to_scalar(&t64) =
UnsignedWide_to_scalar(&now64) / div32;
umul_64by32to64(t64, div32, &t64);
UnsignedWide_to_scalar(&t64) =
UnsignedWide_to_scalar(&now64) - UnsignedWide_to_scalar(&t64);
UnsignedWide_to_scalar(&t64) = ((uint64_t)t64.lo << 32) | now32;
UnsignedWide_to_scalar(&u64) =
UnsignedWide_to_scalar(&t64) / div32;
*result32 = u64.lo;
umul_64by32to64(u64, div32, &u64);
*remain32 = UnsignedWide_to_scalar(&t64) -
UnsignedWide_to_scalar(&u64);
}
else {
UnsignedWide_to_scalar(&t64) = ((uint64_t)now64.lo << 32) | now32;
UnsignedWide_to_scalar(&u64) =
UnsignedWide_to_scalar(&t64) / div32;
*result32 = u64.lo;
umul_64by32to64(u64, div32, &u64);
*remain32 = UnsignedWide_to_scalar(&t64) -
UnsignedWide_to_scalar(&u64);
}
}
/*
* Get the clock device time. This routine is responsible
* for converting the device's machine dependent time value
* into a canonical mach_timespec_t value.
*
* SMP configurations - *the processor clocks are synchronised*
*/
kern_return_t
sysclk_gettime_internal(
mach_timespec_t *time) /* OUT */
{
UnsignedWide now;
UnsignedWide t64;
uint32_t t32;
uint32_t numer, denom;
numer = rtclock.timebase_const.numer;
denom = rtclock.timebase_const.denom;
clock_get_uptime((uint64_t *)&now);
umul_64by32(now, numer, &t64, &t32);
udiv_96by32(t64, t32, denom, &t64, &t32);
udiv_96by32to32and32(t64, t32, NSEC_PER_SEC,
&time->tv_sec, &time->tv_nsec);
return (KERN_SUCCESS);
}
kern_return_t
sysclk_gettime(
mach_timespec_t *time) /* OUT */
{
UnsignedWide now;
UnsignedWide t64;
uint32_t t32;
uint32_t numer, denom;
spl_t s;
LOCK_RTC(s);
numer = rtclock.timebase_const.numer;
denom = rtclock.timebase_const.denom;
UNLOCK_RTC(s);
clock_get_uptime((uint64_t *)&now);
umul_64by32(now, numer, &t64, &t32);
udiv_96by32(t64, t32, denom, &t64, &t32);
udiv_96by32to32and32(t64, t32, NSEC_PER_SEC,
&time->tv_sec, &time->tv_nsec);
return (KERN_SUCCESS);
}
/*
* Get clock device attributes.
*/
kern_return_t
sysclk_getattr(
clock_flavor_t flavor,
clock_attr_t attr, /* OUT */
mach_msg_type_number_t *count) /* IN/OUT */
{
spl_t s;
if (*count != 1)
return (KERN_FAILURE);
switch (flavor) {
case CLOCK_GET_TIME_RES: /* >0 res */
case CLOCK_ALARM_CURRES: /* =0 no alarm */
case CLOCK_ALARM_MINRES:
case CLOCK_ALARM_MAXRES:
LOCK_RTC(s);
*(clock_res_t *) attr = RTC_TICKPERIOD;
UNLOCK_RTC(s);
break;
default:
return (KERN_INVALID_VALUE);
}
return (KERN_SUCCESS);
}
/*
* Set deadline for the next alarm on the clock device. This call
* always resets the time to deliver an alarm for the clock.
*/
void
sysclk_setalarm(
mach_timespec_t *deadline)
{
uint64_t abstime;
timespec_to_absolutetime(*deadline, &abstime);
timer_call_enter(&rtclock.alarm[cpu_number()], abstime);
}
/*
* Configure the calendar clock.
*/
int
calend_config(void)
{
return (1);
}
/*
* Initialize the calendar clock.
*/
int
calend_init(void)
{
if (cpu_number() != master_cpu)
return(1);
return (1);
}
/*
* Get the current clock time.
*/
kern_return_t
calend_gettime(
mach_timespec_t *curr_time) /* OUT */
{
spl_t s;
LOCK_RTC(s);
if (!rtclock.calend_is_set) {
UNLOCK_RTC(s);
return (KERN_FAILURE);
}
(void) sysclk_gettime_internal(curr_time);
ADD_MACH_TIMESPEC(curr_time, &rtclock.calend_offset);
UNLOCK_RTC(s);
return (KERN_SUCCESS);
}
/*
* Set the current clock time.
*/
kern_return_t
calend_settime(
mach_timespec_t *new_time)
{
mach_timespec_t curr_time;
spl_t s;
LOCK_RTC(s);
(void) sysclk_gettime_internal(&curr_time);
rtclock.calend_offset = *new_time;
SUB_MACH_TIMESPEC(&rtclock.calend_offset, &curr_time);
rtclock.calend_is_set = TRUE;
UNLOCK_RTC(s);
PESetGMTTimeOfDay(new_time->tv_sec);
return (KERN_SUCCESS);
}
/*
* Get clock device attributes.
*/
kern_return_t
calend_getattr(
clock_flavor_t flavor,
clock_attr_t attr, /* OUT */
mach_msg_type_number_t *count) /* IN/OUT */
{
spl_t s;
if (*count != 1)
return (KERN_FAILURE);
switch (flavor) {
case CLOCK_GET_TIME_RES: /* >0 res */
LOCK_RTC(s);
*(clock_res_t *) attr = RTC_TICKPERIOD;
UNLOCK_RTC(s);
break;
case CLOCK_ALARM_CURRES: /* =0 no alarm */
case CLOCK_ALARM_MINRES:
case CLOCK_ALARM_MAXRES:
*(clock_res_t *) attr = 0;
break;
default:
return (KERN_INVALID_VALUE);
}
return (KERN_SUCCESS);
}
void
clock_adjust_calendar(
clock_res_t nsec)
{
spl_t s;
LOCK_RTC(s);
if (rtclock.calend_is_set)
ADD_MACH_TIMESPEC_NSEC(&rtclock.calend_offset, nsec);
UNLOCK_RTC(s);
}
void
clock_initialize_calendar(void)
{
mach_timespec_t curr_time;
long seconds = PEGetGMTTimeOfDay();
spl_t s;
LOCK_RTC(s);
(void) sysclk_gettime_internal(&curr_time);
if (curr_time.tv_nsec < 500*USEC_PER_SEC)
rtclock.calend_offset.tv_sec = seconds;
else
rtclock.calend_offset.tv_sec = seconds + 1;
rtclock.calend_offset.tv_nsec = 0;
SUB_MACH_TIMESPEC(&rtclock.calend_offset, &curr_time);
rtclock.calend_is_set = TRUE;
UNLOCK_RTC(s);
}
mach_timespec_t
clock_get_calendar_offset(void)
{
mach_timespec_t result = MACH_TIMESPEC_ZERO;
spl_t s;
LOCK_RTC(s);
if (rtclock.calend_is_set)
result = rtclock.calend_offset;
UNLOCK_RTC(s);
return (result);
}
void
clock_timebase_info(
mach_timebase_info_t info)
{
spl_t s;
LOCK_RTC(s);
*info = rtclock.timebase_const;
UNLOCK_RTC(s);
}
void
clock_set_timer_deadline(
uint64_t deadline)
{
uint64_t abstime;
int decr, mycpu;
struct rtclock_timer *mytimer;
spl_t s;
s = splclock();
mycpu = cpu_number();
mytimer = &rtclock.timer[mycpu];
clock_get_uptime(&abstime);
rtclock.last_abstime[mycpu] = abstime;
mytimer->deadline = deadline;
mytimer->is_set = TRUE;
if ( mytimer->deadline < rtclock_tick_deadline[mycpu] ) {
decr = deadline_to_decrementer(mytimer->deadline, abstime);
if ( rtclock_decrementer_min != 0 &&
rtclock_decrementer_min < (natural_t)decr )
decr = rtclock_decrementer_min;
mtdec(decr);
rtclock.last_decr[mycpu] = decr;
KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_DECI, 1)
| DBG_FUNC_NONE, decr, 2, 0, 0, 0);
}
splx(s);
}
void
clock_set_timer_func(
clock_timer_func_t func)
{
spl_t s;
LOCK_RTC(s);
if (rtclock.timer_expire == NULL)
rtclock.timer_expire = func;
UNLOCK_RTC(s);
}
/*
* Reset the clock device. This causes the realtime clock
* device to reload its mode and count value (frequency).
*/
void
rtclock_reset(void)
{
return;
}
/*
* Real-time clock device interrupt.
*/
void
rtclock_intr(
int device,
struct ppc_saved_state *ssp,
spl_t old_spl)
{
uint64_t abstime;
int decr[3], mycpu = cpu_number();
struct rtclock_timer *mytimer = &rtclock.timer[mycpu];
/*
* We may receive interrupts too early, we must reject them.
*/
if (rtclock_initialized == FALSE) {
mtdec(DECREMENTER_MAX); /* Max the decrementer if not init */
return;
}
decr[1] = decr[2] = DECREMENTER_MAX;
clock_get_uptime(&abstime);
rtclock.last_abstime[mycpu] = abstime;
if ( rtclock_tick_deadline[mycpu] <= abstime ) {
clock_deadline_for_periodic_event(rtclock_tick_interval, abstime,
&rtclock_tick_deadline[mycpu]);
hertz_tick(USER_MODE(ssp->srr1), ssp->srr0);
}
clock_get_uptime(&abstime);
rtclock.last_abstime[mycpu] = abstime;
if ( mytimer->is_set &&
mytimer->deadline <= abstime ) {
mytimer->is_set = FALSE;
(*rtclock.timer_expire)(abstime);
}
clock_get_uptime(&abstime);
rtclock.last_abstime[mycpu] = abstime;
decr[1] = deadline_to_decrementer(rtclock_tick_deadline[mycpu], abstime);
if (mytimer->is_set)
decr[2] = deadline_to_decrementer(mytimer->deadline, abstime);
if (decr[1] > decr[2])
decr[1] = decr[2];
if ( rtclock_decrementer_min != 0 &&
rtclock_decrementer_min < (natural_t)decr[1] )
decr[1] = rtclock_decrementer_min;
mtdec(decr[1]);
rtclock.last_decr[mycpu] = decr[1];
KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_DECI, 1)
| DBG_FUNC_NONE, decr[1], 3, 0, 0, 0);
}
static void
rtclock_alarm_timer(
timer_call_param_t p0,
timer_call_param_t p1)
{
mach_timespec_t timestamp;
(void) sysclk_gettime(×tamp);
clock_alarm_intr(SYSTEM_CLOCK, ×tamp);
}
void
clock_get_uptime(
uint64_t *result0)
{
UnsignedWide *result = (UnsignedWide *)result0;
uint32_t hi, lo, hic;
do {
asm volatile(" mftbu %0" : "=r" (hi));
asm volatile(" mftb %0" : "=r" (lo));
asm volatile(" mftbu %0" : "=r" (hic));
} while (hic != hi);
result->lo = lo;
result->hi = hi;
}
static int
deadline_to_decrementer(
uint64_t deadline,
uint64_t now)
{
uint64_t delt;
if (deadline <= now)
return DECREMENTER_MIN;
else {
delt = deadline - now;
return (delt >= (DECREMENTER_MAX + 1))? DECREMENTER_MAX:
((delt >= (DECREMENTER_MIN + 1))? (delt - 1): DECREMENTER_MIN);
}
}
static void
timespec_to_absolutetime(
mach_timespec_t timespec,
uint64_t *result0)
{
UnsignedWide *result = (UnsignedWide *)result0;
UnsignedWide t64;
uint32_t t32;
uint32_t numer, denom;
spl_t s;
LOCK_RTC(s);
numer = rtclock.timebase_const.numer;
denom = rtclock.timebase_const.denom;
UNLOCK_RTC(s);
asm volatile(" mullw %0,%1,%2" :
"=r" (t64.lo) :
"r" (timespec.tv_sec), "r" (NSEC_PER_SEC));
asm volatile(" mulhwu %0,%1,%2" :
"=r" (t64.hi) :
"r" (timespec.tv_sec), "r" (NSEC_PER_SEC));
UnsignedWide_to_scalar(&t64) += timespec.tv_nsec;
umul_64by32(t64, denom, &t64, &t32);
udiv_96by32(t64, t32, numer, &t64, &t32);
result->hi = t64.lo;
result->lo = t32;
}
void
clock_interval_to_deadline(
uint32_t interval,
uint32_t scale_factor,
uint64_t *result)
{
uint64_t abstime;
clock_get_uptime(result);
clock_interval_to_absolutetime_interval(interval, scale_factor, &abstime);
*result += abstime;
}
void
clock_interval_to_absolutetime_interval(
uint32_t interval,
uint32_t scale_factor,
uint64_t *result0)
{
UnsignedWide *result = (UnsignedWide *)result0;
UnsignedWide t64;
uint32_t t32;
uint32_t numer, denom;
spl_t s;
LOCK_RTC(s);
numer = rtclock.timebase_const.numer;
denom = rtclock.timebase_const.denom;
UNLOCK_RTC(s);
asm volatile(" mullw %0,%1,%2" :
"=r" (t64.lo) :
"r" (interval), "r" (scale_factor));
asm volatile(" mulhwu %0,%1,%2" :
"=r" (t64.hi) :
"r" (interval), "r" (scale_factor));
umul_64by32(t64, denom, &t64, &t32);
udiv_96by32(t64, t32, numer, &t64, &t32);
result->hi = t64.lo;
result->lo = t32;
}
void
clock_absolutetime_interval_to_deadline(
uint64_t abstime,
uint64_t *result)
{
clock_get_uptime(result);
*result += abstime;
}
void
absolutetime_to_nanoseconds(
uint64_t abstime,
uint64_t *result)
{
UnsignedWide t64;
uint32_t t32;
uint32_t numer, denom;
spl_t s;
LOCK_RTC(s);
numer = rtclock.timebase_const.numer;
denom = rtclock.timebase_const.denom;
UNLOCK_RTC(s);
UnsignedWide_to_scalar(&t64) = abstime;
umul_64by32(t64, numer, &t64, &t32);
udiv_96by32to64(t64, t32, denom, (void *)result);
}
void
nanoseconds_to_absolutetime(
uint64_t nanoseconds,
uint64_t *result)
{
UnsignedWide t64;
uint32_t t32;
uint32_t numer, denom;
spl_t s;
LOCK_RTC(s);
numer = rtclock.timebase_const.numer;
denom = rtclock.timebase_const.denom;
UNLOCK_RTC(s);
UnsignedWide_to_scalar(&t64) = nanoseconds;
umul_64by32(t64, denom, &t64, &t32);
udiv_96by32to64(t64, t32, numer, (void *)result);
}
/*
* Spin-loop delay primitives.
*/
void
delay_for_interval(
uint32_t interval,
uint32_t scale_factor)
{
uint64_t now, end;
clock_interval_to_deadline(interval, scale_factor, &end);
do {
clock_get_uptime(&now);
} while (now < end);
}
void
clock_delay_until(
uint64_t deadline)
{
uint64_t now;
do {
clock_get_uptime(&now);
} while (now < deadline);
}
void
delay(
int usec)
{
delay_for_interval((usec < 0)? -usec: usec, NSEC_PER_USEC);
}