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freebsd/sys/pc98/cbus/clock.c
Yoshihiro Takahashi 555c5bb9dd MFi386: sys/i386/isa/clock.c revision 1.175 and 1.176.
2001-09-16 05:29:27 +00:00

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/*-
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz and Don Ahn.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: @(#)clock.c 7.2 (Berkeley) 5/12/91
* $FreeBSD$
*/
/*
* Routines to handle clock hardware.
*/
/*
* inittodr, settodr and support routines written
* by Christoph Robitschko <chmr@edvz.tu-graz.ac.at>
*
* reintroduced and updated by Chris Stenton <chris@gnome.co.uk> 8/10/94
*/
/*
* modified for PC98 by Kakefuda
*/
#include "opt_clock.h"
#include "opt_apm.h"
#include "opt_mca.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/time.h>
#include <sys/timetc.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/cons.h>
#include <machine/clock.h>
#ifdef CLK_CALIBRATION_LOOP
#endif
#include <machine/cputypes.h>
#include <machine/frame.h>
#include <machine/limits.h>
#include <machine/md_var.h>
#include <machine/psl.h>
#ifdef APIC_IO
#include <machine/segments.h>
#endif
#if defined(SMP) || defined(APIC_IO)
#include <machine/smp.h>
#endif /* SMP || APIC_IO */
#include <machine/specialreg.h>
#include <i386/isa/icu.h>
#ifdef PC98
#include <pc98/pc98/pc98.h>
#include <pc98/pc98/pc98_machdep.h>
#include <i386/isa/isa_device.h>
#else
#include <i386/isa/isa.h>
#include <isa/rtc.h>
#endif
#include <isa/isavar.h>
#include <i386/isa/timerreg.h>
#include <i386/isa/intr_machdep.h>
#ifdef DEV_MCA
#include <i386/isa/mca_machdep.h>
#endif
#ifdef APIC_IO
#include <i386/isa/intr_machdep.h>
/* The interrupt triggered by the 8254 (timer) chip */
int apic_8254_intr;
static u_long read_intr_count __P((int vec));
static void setup_8254_mixed_mode __P((void));
#endif
/*
* 32-bit time_t's can't reach leap years before 1904 or after 2036, so we
* can use a simple formula for leap years.
*/
#define LEAPYEAR(y) ((u_int)(y) % 4 == 0)
#define DAYSPERYEAR (31+28+31+30+31+30+31+31+30+31+30+31)
#define TIMER_DIV(x) ((timer_freq + (x) / 2) / (x))
/*
* Time in timer cycles that it takes for microtime() to disable interrupts
* and latch the count. microtime() currently uses "cli; outb ..." so it
* normally takes less than 2 timer cycles. Add a few for cache misses.
* Add a few more to allow for latency in bogus calls to microtime() with
* interrupts already disabled.
*/
#define TIMER0_LATCH_COUNT 20
/*
* Maximum frequency that we are willing to allow for timer0. Must be
* low enough to guarantee that the timer interrupt handler returns
* before the next timer interrupt.
*/
#define TIMER0_MAX_FREQ 20000
int adjkerntz; /* local offset from GMT in seconds */
int clkintr_pending;
int disable_rtc_set; /* disable resettodr() if != 0 */
int statclock_disable;
#ifndef TIMER_FREQ
#ifdef PC98
#define TIMER_FREQ 2457600
#else /* IBM-PC */
#define TIMER_FREQ 1193182
#endif /* PC98 */
#endif
u_int timer_freq = TIMER_FREQ;
int timer0_max_count;
u_int tsc_freq;
int tsc_is_broken;
u_int tsc_present;
int wall_cmos_clock; /* wall CMOS clock assumed if != 0 */
struct mtx clock_lock;
static int beeping = 0;
static const u_char daysinmonth[] = {31,28,31,30,31,30,31,31,30,31,30,31};
static u_int hardclock_max_count;
static u_int32_t i8254_lastcount;
static u_int32_t i8254_offset;
static int i8254_ticked;
/*
* XXX new_function and timer_func should not handle clockframes, but
* timer_func currently needs to hold hardclock to handle the
* timer0_state == 0 case. We should use inthand_add()/inthand_remove()
* to switch between clkintr() and a slightly different timerintr().
*/
static void (*new_function) __P((struct clockframe *frame));
static u_int new_rate;
#ifndef PC98
static u_char rtc_statusa = RTCSA_DIVIDER | RTCSA_NOPROF;
static u_char rtc_statusb = RTCSB_24HR | RTCSB_PINTR;
#endif
static u_int timer0_prescaler_count;
/* Values for timerX_state: */
#define RELEASED 0
#define RELEASE_PENDING 1
#define ACQUIRED 2
#define ACQUIRE_PENDING 3
static u_char timer0_state;
#ifdef PC98
static u_char timer1_state;
#endif
static u_char timer2_state;
static void (*timer_func) __P((struct clockframe *frame)) = hardclock;
#ifdef PC98
static void rtc_serialcombit __P((int));
static void rtc_serialcom __P((int));
static int rtc_inb __P((void));
static void rtc_outb __P((int));
#endif
static unsigned i8254_get_timecount __P((struct timecounter *tc));
static unsigned tsc_get_timecount __P((struct timecounter *tc));
static void set_timer_freq(u_int freq, int intr_freq);
static struct timecounter tsc_timecounter = {
tsc_get_timecount, /* get_timecount */
0, /* no poll_pps */
~0u, /* counter_mask */
0, /* frequency */
"TSC" /* name */
};
SYSCTL_OPAQUE(_debug, OID_AUTO, tsc_timecounter, CTLFLAG_RD,
&tsc_timecounter, sizeof(tsc_timecounter), "S,timecounter", "");
static struct timecounter i8254_timecounter = {
i8254_get_timecount, /* get_timecount */
0, /* no poll_pps */
~0u, /* counter_mask */
0, /* frequency */
"i8254" /* name */
};
SYSCTL_OPAQUE(_debug, OID_AUTO, i8254_timecounter, CTLFLAG_RD,
&i8254_timecounter, sizeof(i8254_timecounter), "S,timecounter", "");
static void
clkintr(struct clockframe frame)
{
if (timecounter->tc_get_timecount == i8254_get_timecount) {
mtx_lock_spin(&clock_lock);
if (i8254_ticked)
i8254_ticked = 0;
else {
i8254_offset += timer0_max_count;
i8254_lastcount = 0;
}
clkintr_pending = 0;
mtx_unlock_spin(&clock_lock);
}
timer_func(&frame);
#ifdef SMP
if (timer_func == hardclock)
forward_hardclock();
#endif
switch (timer0_state) {
case RELEASED:
break;
case ACQUIRED:
if ((timer0_prescaler_count += timer0_max_count)
>= hardclock_max_count) {
timer0_prescaler_count -= hardclock_max_count;
hardclock(&frame);
#ifdef SMP
forward_hardclock();
#endif
}
break;
case ACQUIRE_PENDING:
mtx_lock_spin(&clock_lock);
i8254_offset = i8254_get_timecount(NULL);
i8254_lastcount = 0;
timer0_max_count = TIMER_DIV(new_rate);
outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
outb(TIMER_CNTR0, timer0_max_count & 0xff);
outb(TIMER_CNTR0, timer0_max_count >> 8);
mtx_unlock_spin(&clock_lock);
timer_func = new_function;
timer0_state = ACQUIRED;
break;
case RELEASE_PENDING:
if ((timer0_prescaler_count += timer0_max_count)
>= hardclock_max_count) {
mtx_lock_spin(&clock_lock);
i8254_offset = i8254_get_timecount(NULL);
i8254_lastcount = 0;
timer0_max_count = hardclock_max_count;
outb(TIMER_MODE,
TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
outb(TIMER_CNTR0, timer0_max_count & 0xff);
outb(TIMER_CNTR0, timer0_max_count >> 8);
mtx_unlock_spin(&clock_lock);
timer0_prescaler_count = 0;
timer_func = hardclock;
timer0_state = RELEASED;
hardclock(&frame);
#ifdef SMP
forward_hardclock();
#endif
}
break;
}
#ifdef DEV_MCA
/* Reset clock interrupt by asserting bit 7 of port 0x61 */
if (MCA_system)
outb(0x61, inb(0x61) | 0x80);
#endif
}
/*
* The acquire and release functions must be called at ipl >= splclock().
*/
int
acquire_timer0(int rate, void (*function) __P((struct clockframe *frame)))
{
static int old_rate;
if (rate <= 0 || rate > TIMER0_MAX_FREQ)
return (-1);
switch (timer0_state) {
case RELEASED:
timer0_state = ACQUIRE_PENDING;
break;
case RELEASE_PENDING:
if (rate != old_rate)
return (-1);
/*
* The timer has been released recently, but is being
* re-acquired before the release completed. In this
* case, we simply reclaim it as if it had not been
* released at all.
*/
timer0_state = ACQUIRED;
break;
default:
return (-1); /* busy */
}
new_function = function;
old_rate = new_rate = rate;
return (0);
}
#ifdef PC98
int
acquire_timer1(int mode)
{
if (timer1_state != RELEASED)
return (-1);
timer1_state = ACQUIRED;
/*
* This access to the timer registers is as atomic as possible
* because it is a single instruction. We could do better if we
* knew the rate. Use of splclock() limits glitches to 10-100us,
* and this is probably good enough for timer2, so we aren't as
* careful with it as with timer0.
*/
outb(TIMER_MODE, TIMER_SEL1 | (mode & 0x3f));
return (0);
}
#endif
int
acquire_timer2(int mode)
{
if (timer2_state != RELEASED)
return (-1);
timer2_state = ACQUIRED;
/*
* This access to the timer registers is as atomic as possible
* because it is a single instruction. We could do better if we
* knew the rate. Use of splclock() limits glitches to 10-100us,
* and this is probably good enough for timer2, so we aren't as
* careful with it as with timer0.
*/
outb(TIMER_MODE, TIMER_SEL2 | (mode & 0x3f));
return (0);
}
int
release_timer0()
{
switch (timer0_state) {
case ACQUIRED:
timer0_state = RELEASE_PENDING;
break;
case ACQUIRE_PENDING:
/* Nothing happened yet, release quickly. */
timer0_state = RELEASED;
break;
default:
return (-1);
}
return (0);
}
#ifdef PC98
int
release_timer1()
{
if (timer1_state != ACQUIRED)
return (-1);
timer1_state = RELEASED;
outb(TIMER_MODE, TIMER_SEL1 | TIMER_SQWAVE | TIMER_16BIT);
return (0);
}
#endif
int
release_timer2()
{
if (timer2_state != ACQUIRED)
return (-1);
timer2_state = RELEASED;
outb(TIMER_MODE, TIMER_SEL2 | TIMER_SQWAVE | TIMER_16BIT);
return (0);
}
#ifndef PC98
/*
* This routine receives statistical clock interrupts from the RTC.
* As explained above, these occur at 128 interrupts per second.
* When profiling, we receive interrupts at a rate of 1024 Hz.
*
* This does not actually add as much overhead as it sounds, because
* when the statistical clock is active, the hardclock driver no longer
* needs to keep (inaccurate) statistics on its own. This decouples
* statistics gathering from scheduling interrupts.
*
* The RTC chip requires that we read status register C (RTC_INTR)
* to acknowledge an interrupt, before it will generate the next one.
* Under high interrupt load, rtcintr() can be indefinitely delayed and
* the clock can tick immediately after the read from RTC_INTR. In this
* case, the mc146818A interrupt signal will not drop for long enough
* to register with the 8259 PIC. If an interrupt is missed, the stat
* clock will halt, considerably degrading system performance. This is
* why we use 'while' rather than a more straightforward 'if' below.
* Stat clock ticks can still be lost, causing minor loss of accuracy
* in the statistics, but the stat clock will no longer stop.
*/
static void
rtcintr(struct clockframe frame)
{
while (rtcin(RTC_INTR) & RTCIR_PERIOD) {
statclock(&frame);
#ifdef SMP
forward_statclock();
#endif
}
}
#include "opt_ddb.h"
#ifdef DDB
#include <ddb/ddb.h>
DB_SHOW_COMMAND(rtc, rtc)
{
printf("%02x/%02x/%02x %02x:%02x:%02x, A = %02x, B = %02x, C = %02x\n",
rtcin(RTC_YEAR), rtcin(RTC_MONTH), rtcin(RTC_DAY),
rtcin(RTC_HRS), rtcin(RTC_MIN), rtcin(RTC_SEC),
rtcin(RTC_STATUSA), rtcin(RTC_STATUSB), rtcin(RTC_INTR));
}
#endif /* DDB */
#endif /* for PC98 */
static int
getit(void)
{
int high, low;
mtx_lock_spin(&clock_lock);
/* Select timer0 and latch counter value. */
outb(TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
low = inb(TIMER_CNTR0);
high = inb(TIMER_CNTR0);
mtx_unlock_spin(&clock_lock);
return ((high << 8) | low);
}
/*
* Wait "n" microseconds.
* Relies on timer 1 counting down from (timer_freq / hz)
* Note: timer had better have been programmed before this is first used!
*/
void
DELAY(int n)
{
int delta, prev_tick, tick, ticks_left;
#ifdef DELAYDEBUG
int getit_calls = 1;
int n1;
static int state = 0;
if (state == 0) {
state = 1;
for (n1 = 1; n1 <= 10000000; n1 *= 10)
DELAY(n1);
state = 2;
}
if (state == 1)
printf("DELAY(%d)...", n);
#endif
/*
* Guard against the timer being uninitialized if we are called
* early for console i/o.
*/
if (timer0_max_count == 0)
set_timer_freq(timer_freq, hz);
/*
* Read the counter first, so that the rest of the setup overhead is
* counted. Guess the initial overhead is 20 usec (on most systems it
* takes about 1.5 usec for each of the i/o's in getit(). The loop
* takes about 6 usec on a 486/33 and 13 usec on a 386/20. The
* multiplications and divisions to scale the count take a while).
*/
prev_tick = getit();
n -= 0; /* XXX actually guess no initial overhead */
/*
* Calculate (n * (timer_freq / 1e6)) without using floating point
* and without any avoidable overflows.
*/
if (n <= 0)
ticks_left = 0;
else if (n < 256)
/*
* Use fixed point to avoid a slow division by 1000000.
* 39099 = 1193182 * 2^15 / 10^6 rounded to nearest.
* 2^15 is the first power of 2 that gives exact results
* for n between 0 and 256.
*/
ticks_left = ((u_int)n * 39099 + (1 << 15) - 1) >> 15;
else
/*
* Don't bother using fixed point, although gcc-2.7.2
* generates particularly poor code for the long long
* division, since even the slow way will complete long
* before the delay is up (unless we're interrupted).
*/
ticks_left = ((u_int)n * (long long)timer_freq + 999999)
/ 1000000;
while (ticks_left > 0) {
tick = getit();
#ifdef DELAYDEBUG
++getit_calls;
#endif
delta = prev_tick - tick;
prev_tick = tick;
if (delta < 0) {
delta += timer0_max_count;
/*
* Guard against timer0_max_count being wrong.
* This shouldn't happen in normal operation,
* but it may happen if set_timer_freq() is
* traced.
*/
if (delta < 0)
delta = 0;
}
ticks_left -= delta;
}
#ifdef DELAYDEBUG
if (state == 1)
printf(" %d calls to getit() at %d usec each\n",
getit_calls, (n + 5) / getit_calls);
#endif
}
static void
sysbeepstop(void *chan)
{
#ifdef PC98 /* PC98 */
outb(IO_PPI, inb(IO_PPI)|0x08); /* disable counter1 output to speaker */
release_timer1();
#else
outb(IO_PPI, inb(IO_PPI)&0xFC); /* disable counter2 output to speaker */
release_timer2();
#endif
beeping = 0;
}
int
sysbeep(int pitch, int period)
{
int x = splclock();
#ifdef PC98
if (acquire_timer1(TIMER_SQWAVE|TIMER_16BIT))
if (!beeping) {
/* Something else owns it. */
splx(x);
return (-1); /* XXX Should be EBUSY, but nobody cares anyway. */
}
disable_intr();
outb(0x3fdb, pitch);
outb(0x3fdb, (pitch>>8));
enable_intr();
if (!beeping) {
/* enable counter1 output to speaker */
outb(IO_PPI, (inb(IO_PPI) & 0xf7));
beeping = period;
timeout(sysbeepstop, (void *)NULL, period);
}
#else
if (acquire_timer2(TIMER_SQWAVE|TIMER_16BIT))
if (!beeping) {
/* Something else owns it. */
splx(x);
return (-1); /* XXX Should be EBUSY, but nobody cares anyway. */
}
mtx_lock_spin(&clock_lock);
outb(TIMER_CNTR2, pitch);
outb(TIMER_CNTR2, (pitch>>8));
mtx_unlock_spin(&clock_lock);
if (!beeping) {
/* enable counter2 output to speaker */
outb(IO_PPI, inb(IO_PPI) | 3);
beeping = period;
timeout(sysbeepstop, (void *)NULL, period);
}
#endif
splx(x);
return (0);
}
#ifndef PC98
/*
* RTC support routines
*/
int
rtcin(reg)
int reg;
{
int s;
u_char val;
s = splhigh();
outb(IO_RTC, reg);
inb(0x84);
val = inb(IO_RTC + 1);
inb(0x84);
splx(s);
return (val);
}
static __inline void
writertc(u_char reg, u_char val)
{
int s;
s = splhigh();
inb(0x84);
outb(IO_RTC, reg);
inb(0x84);
outb(IO_RTC + 1, val);
inb(0x84); /* XXX work around wrong order in rtcin() */
splx(s);
}
static __inline int
readrtc(int port)
{
return(bcd2bin(rtcin(port)));
}
#endif
#ifdef PC98
unsigned int delaycount;
#define FIRST_GUESS 0x2000
static void findcpuspeed(void)
{
int i;
int remainder;
/* Put counter in count down mode */
outb(TIMER_MODE, TIMER_SEL0 | TIMER_16BIT | TIMER_RATEGEN);
outb(TIMER_CNTR0, 0xff);
outb(TIMER_CNTR0, 0xff);
for (i = FIRST_GUESS; i; i--)
;
remainder = getit();
delaycount = (FIRST_GUESS * TIMER_DIV(1000)) / (0xffff - remainder);
}
#endif
#ifdef PC98
static u_int
calibrate_clocks(void)
{
int timeout;
u_int count, prev_count, tot_count;
u_short sec, start_sec;
if (bootverbose)
printf("Calibrating clock(s) ... ");
/* Check ARTIC. */
if (!(PC98_SYSTEM_PARAMETER(0x458) & 0x80) &&
!(PC98_SYSTEM_PARAMETER(0x45b) & 0x04))
goto fail;
timeout = 100000000;
/* Read the ARTIC. */
sec = inw(0x5e);
/* Wait for the ARTIC to changes. */
start_sec = sec;
for (;;) {
sec = inw(0x5e);
if (sec != start_sec)
break;
if (--timeout == 0)
goto fail;
}
prev_count = getit();
if (prev_count == 0 || prev_count > timer0_max_count)
goto fail;
tot_count = 0;
if (tsc_present)
wrmsr(0x10, 0LL); /* XXX 0x10 is the MSR for the TSC */
start_sec = sec;
for (;;) {
sec = inw(0x5e);
count = getit();
if (count == 0 || count > timer0_max_count)
goto fail;
if (count > prev_count)
tot_count += prev_count - (count - timer0_max_count);
else
tot_count += prev_count - count;
prev_count = count;
if ((sec == start_sec + 1200) ||
(sec < start_sec &&
(u_int)sec + 0x10000 == (u_int)start_sec + 1200))
break;
if (--timeout == 0)
goto fail;
}
/*
* Read the cpu cycle counter. The timing considerations are
* similar to those for the i8254 clock.
*/
if (tsc_present)
tsc_freq = rdtsc();
if (bootverbose) {
if (tsc_present)
printf("TSC clock: %u Hz, ", tsc_freq);
printf("i8254 clock: %u Hz\n", tot_count);
}
return (tot_count);
fail:
if (bootverbose)
printf("failed, using default i8254 clock of %u Hz\n",
timer_freq);
return (timer_freq);
}
#else
static u_int
calibrate_clocks(void)
{
u_int64_t old_tsc;
u_int count, prev_count, tot_count;
int sec, start_sec, timeout;
if (bootverbose)
printf("Calibrating clock(s) ... ");
if (!(rtcin(RTC_STATUSD) & RTCSD_PWR))
goto fail;
timeout = 100000000;
/* Read the mc146818A seconds counter. */
for (;;) {
if (!(rtcin(RTC_STATUSA) & RTCSA_TUP)) {
sec = rtcin(RTC_SEC);
break;
}
if (--timeout == 0)
goto fail;
}
/* Wait for the mC146818A seconds counter to change. */
start_sec = sec;
for (;;) {
if (!(rtcin(RTC_STATUSA) & RTCSA_TUP)) {
sec = rtcin(RTC_SEC);
if (sec != start_sec)
break;
}
if (--timeout == 0)
goto fail;
}
/* Start keeping track of the i8254 counter. */
prev_count = getit();
if (prev_count == 0 || prev_count > timer0_max_count)
goto fail;
tot_count = 0;
if (tsc_present)
old_tsc = rdtsc();
else
old_tsc = 0; /* shut up gcc */
/*
* Wait for the mc146818A seconds counter to change. Read the i8254
* counter for each iteration since this is convenient and only
* costs a few usec of inaccuracy. The timing of the final reads
* of the counters almost matches the timing of the initial reads,
* so the main cause of inaccuracy is the varying latency from
* inside getit() or rtcin(RTC_STATUSA) to the beginning of the
* rtcin(RTC_SEC) that returns a changed seconds count. The
* maximum inaccuracy from this cause is < 10 usec on 486's.
*/
start_sec = sec;
for (;;) {
if (!(rtcin(RTC_STATUSA) & RTCSA_TUP))
sec = rtcin(RTC_SEC);
count = getit();
if (count == 0 || count > timer0_max_count)
goto fail;
if (count > prev_count)
tot_count += prev_count - (count - timer0_max_count);
else
tot_count += prev_count - count;
prev_count = count;
if (sec != start_sec)
break;
if (--timeout == 0)
goto fail;
}
/*
* Read the cpu cycle counter. The timing considerations are
* similar to those for the i8254 clock.
*/
if (tsc_present)
tsc_freq = rdtsc() - old_tsc;
if (bootverbose) {
if (tsc_present)
printf("TSC clock: %u Hz, ", tsc_freq);
printf("i8254 clock: %u Hz\n", tot_count);
}
return (tot_count);
fail:
if (bootverbose)
printf("failed, using default i8254 clock of %u Hz\n",
timer_freq);
return (timer_freq);
}
#endif /* !PC98 */
static void
set_timer_freq(u_int freq, int intr_freq)
{
int new_timer0_max_count;
mtx_lock_spin(&clock_lock);
timer_freq = freq;
new_timer0_max_count = hardclock_max_count = TIMER_DIV(intr_freq);
if (new_timer0_max_count != timer0_max_count) {
timer0_max_count = new_timer0_max_count;
outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
outb(TIMER_CNTR0, timer0_max_count & 0xff);
outb(TIMER_CNTR0, timer0_max_count >> 8);
}
mtx_unlock_spin(&clock_lock);
}
/*
* i8254_restore is called from apm_default_resume() to reload
* the countdown register.
* this should not be necessary but there are broken laptops that
* do not restore the countdown register on resume.
* when it happnes, it messes up the hardclock interval and system clock,
* which leads to the infamous "calcru: negative time" problem.
*/
static void
i8254_restore(void)
{
mtx_lock_spin(&clock_lock);
outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
outb(TIMER_CNTR0, timer0_max_count & 0xff);
outb(TIMER_CNTR0, timer0_max_count >> 8);
mtx_unlock_spin(&clock_lock);
}
#ifndef PC98
static void
rtc_restore(void)
{
/* Reenable RTC updates and interrupts. */
/* XXX locking is needed for RTC access? */
writertc(RTC_STATUSB, RTCSB_HALT | RTCSB_24HR);
writertc(RTC_STATUSB, rtc_statusb);
}
#endif
/*
* Restore all the timers atomically.
*/
void
timer_restore(void)
{
i8254_restore(); /* restore timer_freq and hz */
#ifndef PC98
rtc_restore(); /* reenable RTC interrupts */
#endif
}
/*
* Initialize 8254 timer 0 early so that it can be used in DELAY().
* XXX initialization of other timers is unintentionally left blank.
*/
void
startrtclock()
{
u_int delta, freq;
#ifdef PC98
findcpuspeed();
if (pc98_machine_type & M_8M)
timer_freq = 1996800L; /* 1.9968 MHz */
else
timer_freq = 2457600L; /* 2.4576 MHz */
#endif /* PC98 */
if (cpu_feature & CPUID_TSC)
tsc_present = 1;
else
tsc_present = 0;
#ifndef PC98
writertc(RTC_STATUSA, rtc_statusa);
writertc(RTC_STATUSB, RTCSB_24HR);
#endif
set_timer_freq(timer_freq, hz);
freq = calibrate_clocks();
#ifdef CLK_CALIBRATION_LOOP
if (bootverbose) {
printf(
"Press a key on the console to abort clock calibration\n");
while (cncheckc() == -1)
calibrate_clocks();
}
#endif
/*
* Use the calibrated i8254 frequency if it seems reasonable.
* Otherwise use the default, and don't use the calibrated i586
* frequency.
*/
delta = freq > timer_freq ? freq - timer_freq : timer_freq - freq;
if (delta < timer_freq / 100) {
#ifndef CLK_USE_I8254_CALIBRATION
if (bootverbose)
printf(
"CLK_USE_I8254_CALIBRATION not specified - using default frequency\n");
freq = timer_freq;
#endif
timer_freq = freq;
} else {
if (bootverbose)
printf(
"%d Hz differs from default of %d Hz by more than 1%%\n",
freq, timer_freq);
tsc_freq = 0;
}
set_timer_freq(timer_freq, hz);
i8254_timecounter.tc_frequency = timer_freq;
tc_init(&i8254_timecounter);
#ifndef CLK_USE_TSC_CALIBRATION
if (tsc_freq != 0) {
if (bootverbose)
printf(
"CLK_USE_TSC_CALIBRATION not specified - using old calibration method\n");
tsc_freq = 0;
}
#endif
if (tsc_present && tsc_freq == 0) {
/*
* Calibration of the i586 clock relative to the mc146818A
* clock failed. Do a less accurate calibration relative
* to the i8254 clock.
*/
u_int64_t old_tsc = rdtsc();
DELAY(1000000);
tsc_freq = rdtsc() - old_tsc;
#ifdef CLK_USE_TSC_CALIBRATION
if (bootverbose)
printf("TSC clock: %u Hz (Method B)\n", tsc_freq);
#endif
}
#if !defined(SMP)
/*
* We can not use the TSC in SMP mode, until we figure out a
* cheap (impossible), reliable and precise (yeah right!) way
* to synchronize the TSCs of all the CPUs.
* Curse Intel for leaving the counter out of the I/O APIC.
*/
#ifdef DEV_APM
/*
* We can not use the TSC if we support APM. Precise timekeeping
* on an APM'ed machine is at best a fools pursuit, since
* any and all of the time spent in various SMM code can't
* be reliably accounted for. Reading the RTC is your only
* source of reliable time info. The i8254 looses too of course
* but we need to have some kind of time...
* We don't know at this point whether APM is going to be used
* or not, nor when it might be activated. Play it safe.
*/
{
int disabled = 0;
resource_int_value("apm", 0, "disabled", &disabled);
if (disabled == 0)
return;
}
#endif /* DEV_APM */
if (tsc_present && tsc_freq != 0 && !tsc_is_broken) {
tsc_timecounter.tc_frequency = tsc_freq;
tc_init(&tsc_timecounter);
}
#endif /* !defined(SMP) */
}
#ifdef PC98
static void
rtc_serialcombit(int i)
{
outb(IO_RTC, ((i&0x01)<<5)|0x07);
DELAY(1);
outb(IO_RTC, ((i&0x01)<<5)|0x17);
DELAY(1);
outb(IO_RTC, ((i&0x01)<<5)|0x07);
DELAY(1);
}
static void
rtc_serialcom(int i)
{
rtc_serialcombit(i&0x01);
rtc_serialcombit((i&0x02)>>1);
rtc_serialcombit((i&0x04)>>2);
rtc_serialcombit((i&0x08)>>3);
outb(IO_RTC, 0x07);
DELAY(1);
outb(IO_RTC, 0x0f);
DELAY(1);
outb(IO_RTC, 0x07);
DELAY(1);
}
static void
rtc_outb(int val)
{
int s;
int sa = 0;
for (s=0;s<8;s++) {
sa = ((val >> s) & 0x01) ? 0x27 : 0x07;
outb(IO_RTC, sa); /* set DI & CLK 0 */
DELAY(1);
outb(IO_RTC, sa | 0x10); /* CLK 1 */
DELAY(1);
}
outb(IO_RTC, sa & 0xef); /* CLK 0 */
}
static int
rtc_inb(void)
{
int s;
int sa = 0;
for (s=0;s<8;s++) {
sa |= ((inb(0x33) & 0x01) << s);
outb(IO_RTC, 0x17); /* CLK 1 */
DELAY(1);
outb(IO_RTC, 0x07); /* CLK 0 */
DELAY(2);
}
return sa;
}
#endif /* PC-98 */
/*
* Initialize the time of day register, based on the time base which is, e.g.
* from a filesystem.
*/
void
inittodr(time_t base)
{
unsigned long sec, days;
#ifndef PC98
int yd;
#endif
int year, month;
int y, m, s;
struct timespec ts;
#ifdef PC98
int second, min, hour;
#endif
if (base) {
s = splclock();
ts.tv_sec = base;
ts.tv_nsec = 0;
tc_setclock(&ts);
splx(s);
}
#ifdef PC98
rtc_serialcom(0x03); /* Time Read */
rtc_serialcom(0x01); /* Register shift command. */
DELAY(20);
second = bcd2bin(rtc_inb() & 0xff); /* sec */
min = bcd2bin(rtc_inb() & 0xff); /* min */
hour = bcd2bin(rtc_inb() & 0xff); /* hour */
days = bcd2bin(rtc_inb() & 0xff) - 1; /* date */
month = (rtc_inb() >> 4) & 0x0f; /* month */
for (m = 1; m < month; m++)
days += daysinmonth[m-1];
year = bcd2bin(rtc_inb() & 0xff) + 1900; /* year */
/* 2000 year problem */
if (year < 1995)
year += 100;
if (year < 1970)
goto wrong_time;
for (y = 1970; y < year; y++)
days += DAYSPERYEAR + LEAPYEAR(y);
if ((month > 2) && LEAPYEAR(year))
days ++;
sec = ((( days * 24 +
hour) * 60 +
min) * 60 +
second);
/* sec now contains the number of seconds, since Jan 1 1970,
in the local time zone */
s = splhigh();
#else /* IBM-PC */
/* Look if we have a RTC present and the time is valid */
if (!(rtcin(RTC_STATUSD) & RTCSD_PWR))
goto wrong_time;
/* wait for time update to complete */
/* If RTCSA_TUP is zero, we have at least 244us before next update */
s = splhigh();
while (rtcin(RTC_STATUSA) & RTCSA_TUP) {
splx(s);
s = splhigh();
}
days = 0;
#ifdef USE_RTC_CENTURY
year = readrtc(RTC_YEAR) + readrtc(RTC_CENTURY) * 100;
#else
year = readrtc(RTC_YEAR) + 1900;
if (year < 1970)
year += 100;
#endif
if (year < 1970) {
splx(s);
goto wrong_time;
}
month = readrtc(RTC_MONTH);
for (m = 1; m < month; m++)
days += daysinmonth[m-1];
if ((month > 2) && LEAPYEAR(year))
days ++;
days += readrtc(RTC_DAY) - 1;
yd = days;
for (y = 1970; y < year; y++)
days += DAYSPERYEAR + LEAPYEAR(y);
sec = ((( days * 24 +
readrtc(RTC_HRS)) * 60 +
readrtc(RTC_MIN)) * 60 +
readrtc(RTC_SEC));
/* sec now contains the number of seconds, since Jan 1 1970,
in the local time zone */
#endif
sec += tz.tz_minuteswest * 60 + (wall_cmos_clock ? adjkerntz : 0);
y = time_second - sec;
if (y <= -2 || y >= 2) {
/* badly off, adjust it */
ts.tv_sec = sec;
ts.tv_nsec = 0;
tc_setclock(&ts);
}
splx(s);
return;
wrong_time:
printf("Invalid time in real time clock.\n");
printf("Check and reset the date immediately!\n");
}
/*
* Write system time back to RTC
*/
void
resettodr()
{
unsigned long tm;
int y, m, s;
#ifdef PC98
int wd;
#endif
if (disable_rtc_set)
return;
s = splclock();
tm = time_second;
splx(s);
#ifdef PC98
rtc_serialcom(0x01); /* Register shift command. */
/* Calculate local time to put in RTC */
tm -= tz.tz_minuteswest * 60 + (wall_cmos_clock ? adjkerntz : 0);
rtc_outb(bin2bcd(tm%60)); tm /= 60; /* Write back Seconds */
rtc_outb(bin2bcd(tm%60)); tm /= 60; /* Write back Minutes */
rtc_outb(bin2bcd(tm%24)); tm /= 24; /* Write back Hours */
/* We have now the days since 01-01-1970 in tm */
wd = (tm+4)%7;
for (y = 1970, m = DAYSPERYEAR + LEAPYEAR(y);
tm >= m;
y++, m = DAYSPERYEAR + LEAPYEAR(y))
tm -= m;
/* Now we have the years in y and the day-of-the-year in tm */
for (m = 0; ; m++) {
int ml;
ml = daysinmonth[m];
if (m == 1 && LEAPYEAR(y))
ml++;
if (tm < ml)
break;
tm -= ml;
}
m++;
rtc_outb(bin2bcd(tm+1)); /* Write back Day */
rtc_outb((m << 4) | wd); /* Write back Month & Weekday */
rtc_outb(bin2bcd(y%100)); /* Write back Year */
rtc_serialcom(0x02); /* Time set & Counter hold command. */
rtc_serialcom(0x00); /* Register hold command. */
#else
/* Disable RTC updates and interrupts. */
writertc(RTC_STATUSB, RTCSB_HALT | RTCSB_24HR);
/* Calculate local time to put in RTC */
tm -= tz.tz_minuteswest * 60 + (wall_cmos_clock ? adjkerntz : 0);
writertc(RTC_SEC, bin2bcd(tm%60)); tm /= 60; /* Write back Seconds */
writertc(RTC_MIN, bin2bcd(tm%60)); tm /= 60; /* Write back Minutes */
writertc(RTC_HRS, bin2bcd(tm%24)); tm /= 24; /* Write back Hours */
/* We have now the days since 01-01-1970 in tm */
writertc(RTC_WDAY, (tm+4)%7); /* Write back Weekday */
for (y = 1970, m = DAYSPERYEAR + LEAPYEAR(y);
tm >= m;
y++, m = DAYSPERYEAR + LEAPYEAR(y))
tm -= m;
/* Now we have the years in y and the day-of-the-year in tm */
writertc(RTC_YEAR, bin2bcd(y%100)); /* Write back Year */
#ifdef USE_RTC_CENTURY
writertc(RTC_CENTURY, bin2bcd(y/100)); /* ... and Century */
#endif
for (m = 0; ; m++) {
int ml;
ml = daysinmonth[m];
if (m == 1 && LEAPYEAR(y))
ml++;
if (tm < ml)
break;
tm -= ml;
}
writertc(RTC_MONTH, bin2bcd(m + 1)); /* Write back Month */
writertc(RTC_DAY, bin2bcd(tm + 1)); /* Write back Month Day */
/* Reenable RTC updates and interrupts. */
writertc(RTC_STATUSB, rtc_statusb);
#endif /* PC98 */
}
/*
* Start both clocks running.
*/
void
cpu_initclocks()
{
#ifndef PC98
int diag;
#endif
#ifdef APIC_IO
int apic_8254_trial;
void *clkdesc;
#endif /* APIC_IO */
#ifndef PC98
if (statclock_disable) {
/*
* The stat interrupt mask is different without the
* statistics clock. Also, don't set the interrupt
* flag which would normally cause the RTC to generate
* interrupts.
*/
rtc_statusb = RTCSB_24HR;
} else {
/* Setting stathz to nonzero early helps avoid races. */
stathz = RTC_NOPROFRATE;
profhz = RTC_PROFRATE;
}
#endif
/* Finish initializing 8253 timer 0. */
#ifdef APIC_IO
apic_8254_intr = isa_apic_irq(0);
apic_8254_trial = 0;
if (apic_8254_intr >= 0 ) {
if (apic_int_type(0, 0) == 3)
apic_8254_trial = 1;
} else {
/* look for ExtInt on pin 0 */
if (apic_int_type(0, 0) == 3) {
apic_8254_intr = apic_irq(0, 0);
setup_8254_mixed_mode();
} else
panic("APIC_IO: Cannot route 8254 interrupt to CPU");
}
inthand_add("clk", apic_8254_intr, (driver_intr_t *)clkintr, NULL,
INTR_TYPE_CLK | INTR_FAST, &clkdesc);
INTREN(1 << apic_8254_intr);
#else /* APIC_IO */
/*
* XXX Check the priority of this interrupt handler. I
* couldn't find anything suitable in the BSD/OS code (grog,
* 19 July 2000).
*/
inthand_add("clk", 0, (driver_intr_t *)clkintr, NULL,
INTR_TYPE_CLK | INTR_FAST, NULL);
INTREN(IRQ0);
#endif /* APIC_IO */
#ifndef PC98
/* Initialize RTC. */
writertc(RTC_STATUSA, rtc_statusa);
writertc(RTC_STATUSB, RTCSB_24HR);
/* Don't bother enabling the statistics clock. */
if (statclock_disable)
return;
diag = rtcin(RTC_DIAG);
if (diag != 0)
printf("RTC BIOS diagnostic error %b\n", diag, RTCDG_BITS);
#endif /* !PC98 */
#ifndef PC98
#ifdef APIC_IO
if (isa_apic_irq(8) != 8)
panic("APIC RTC != 8");
#endif /* APIC_IO */
inthand_add("rtc", 8, (driver_intr_t *)rtcintr, NULL,
INTR_TYPE_CLK | INTR_FAST, NULL);
#ifdef APIC_IO
INTREN(APIC_IRQ8);
#else
INTREN(IRQ8);
#endif /* APIC_IO */
writertc(RTC_STATUSB, rtc_statusb);
#endif /* PC98 */
#ifdef APIC_IO
if (apic_8254_trial) {
printf("APIC_IO: Testing 8254 interrupt delivery\n");
while (read_intr_count(8) < 6)
; /* nothing */
if (read_intr_count(apic_8254_intr) < 3) {
/*
* The MP table is broken.
* The 8254 was not connected to the specified pin
* on the IO APIC.
* Workaround: Limited variant of mixed mode.
*/
INTRDIS(1 << apic_8254_intr);
inthand_remove(clkdesc);
printf("APIC_IO: Broken MP table detected: "
"8254 is not connected to "
"IOAPIC #%d intpin %d\n",
int_to_apicintpin[apic_8254_intr].ioapic,
int_to_apicintpin[apic_8254_intr].int_pin);
/*
* Revoke current ISA IRQ 0 assignment and
* configure a fallback interrupt routing from
* the 8254 Timer via the 8259 PIC to the
* an ExtInt interrupt line on IOAPIC #0 intpin 0.
* We reuse the low level interrupt handler number.
*/
if (apic_irq(0, 0) < 0) {
revoke_apic_irq(apic_8254_intr);
assign_apic_irq(0, 0, apic_8254_intr);
}
apic_8254_intr = apic_irq(0, 0);
setup_8254_mixed_mode();
inthand_add("clk", apic_8254_intr,
(driver_intr_t *)clkintr, NULL,
INTR_TYPE_CLK | INTR_FAST, NULL);
INTREN(1 << apic_8254_intr);
}
}
if (apic_int_type(0, 0) != 3 ||
int_to_apicintpin[apic_8254_intr].ioapic != 0 ||
int_to_apicintpin[apic_8254_intr].int_pin != 0)
printf("APIC_IO: routing 8254 via IOAPIC #%d intpin %d\n",
int_to_apicintpin[apic_8254_intr].ioapic,
int_to_apicintpin[apic_8254_intr].int_pin);
else
printf("APIC_IO: "
"routing 8254 via 8259 and IOAPIC #0 intpin 0\n");
#endif
}
#ifdef APIC_IO
static u_long
read_intr_count(int vec)
{
u_long *up;
up = intr_countp[vec];
if (up)
return *up;
return 0UL;
}
static void
setup_8254_mixed_mode()
{
/*
* Allow 8254 timer to INTerrupt 8259:
* re-initialize master 8259:
* reset; prog 4 bytes, single ICU, edge triggered
*/
outb(IO_ICU1, 0x13);
#ifdef PC98
outb(IO_ICU1 + 2, NRSVIDT); /* start vector (unused) */
outb(IO_ICU1 + 2, 0x00); /* ignore slave */
outb(IO_ICU1 + 2, 0x03); /* auto EOI, 8086 */
outb(IO_ICU1 + 2, 0xfe); /* unmask INT0 */
#else
outb(IO_ICU1 + 1, NRSVIDT); /* start vector (unused) */
outb(IO_ICU1 + 1, 0x00); /* ignore slave */
outb(IO_ICU1 + 1, 0x03); /* auto EOI, 8086 */
outb(IO_ICU1 + 1, 0xfe); /* unmask INT0 */
#endif
/* program IO APIC for type 3 INT on INT0 */
if (ext_int_setup(0, 0) < 0)
panic("8254 redirect via APIC pin0 impossible!");
}
#endif
void
setstatclockrate(int newhz)
{
#ifndef PC98
if (newhz == RTC_PROFRATE)
rtc_statusa = RTCSA_DIVIDER | RTCSA_PROF;
else
rtc_statusa = RTCSA_DIVIDER | RTCSA_NOPROF;
writertc(RTC_STATUSA, rtc_statusa);
#endif
}
static int
sysctl_machdep_i8254_freq(SYSCTL_HANDLER_ARGS)
{
int error;
u_int freq;
/*
* Use `i8254' instead of `timer' in external names because `timer'
* is is too generic. Should use it everywhere.
*/
freq = timer_freq;
error = sysctl_handle_int(oidp, &freq, sizeof(freq), req);
if (error == 0 && req->newptr != NULL) {
if (timer0_state != RELEASED)
return (EBUSY); /* too much trouble to handle */
set_timer_freq(freq, hz);
i8254_timecounter.tc_frequency = freq;
tc_update(&i8254_timecounter);
}
return (error);
}
SYSCTL_PROC(_machdep, OID_AUTO, i8254_freq, CTLTYPE_INT | CTLFLAG_RW,
0, sizeof(u_int), sysctl_machdep_i8254_freq, "I", "");
static int
sysctl_machdep_tsc_freq(SYSCTL_HANDLER_ARGS)
{
int error;
u_int freq;
if (tsc_timecounter.tc_frequency == 0)
return (EOPNOTSUPP);
freq = tsc_freq;
error = sysctl_handle_int(oidp, &freq, sizeof(freq), req);
if (error == 0 && req->newptr != NULL) {
tsc_freq = freq;
tsc_timecounter.tc_frequency = tsc_freq;
tc_update(&tsc_timecounter);
}
return (error);
}
SYSCTL_PROC(_machdep, OID_AUTO, tsc_freq, CTLTYPE_INT | CTLFLAG_RW,
0, sizeof(u_int), sysctl_machdep_tsc_freq, "I", "");
static unsigned
i8254_get_timecount(struct timecounter *tc)
{
u_int count;
u_int high, low;
u_int eflags;
eflags = read_eflags();
mtx_lock_spin(&clock_lock);
/* Select timer0 and latch counter value. */
outb(TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
low = inb(TIMER_CNTR0);
high = inb(TIMER_CNTR0);
count = timer0_max_count - ((high << 8) | low);
if (count < i8254_lastcount ||
(!i8254_ticked && (clkintr_pending ||
((count < 20 || (!(eflags & PSL_I) && count < timer0_max_count / 2u)) &&
#ifdef APIC_IO
#define lapic_irr1 ((volatile u_int *)&lapic)[0x210 / 4] /* XXX XXX */
/* XXX this assumes that apic_8254_intr is < 24. */
(lapic_irr1 & (1 << apic_8254_intr))))
#else
(inb(IO_ICU1) & 1)))
#endif
)) {
i8254_ticked = 1;
i8254_offset += timer0_max_count;
}
i8254_lastcount = count;
count += i8254_offset;
mtx_unlock_spin(&clock_lock);
return (count);
}
static unsigned
tsc_get_timecount(struct timecounter *tc)
{
return (rdtsc());
}
/*
* Attach to the ISA PnP descriptors for the timer and realtime clock.
*/
static struct isa_pnp_id attimer_ids[] = {
{ 0x0001d041 /* PNP0100 */, "AT timer" },
{ 0x000bd041 /* PNP0B00 */, "AT realtime clock" },
{ 0 }
};
static int
attimer_probe(device_t dev)
{
int result;
if ((result = ISA_PNP_PROBE(device_get_parent(dev), dev, attimer_ids)) <= 0)
device_quiet(dev);
return(result);
}
static int
attimer_attach(device_t dev)
{
return(0);
}
static device_method_t attimer_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, attimer_probe),
DEVMETHOD(device_attach, attimer_attach),
DEVMETHOD(device_detach, bus_generic_detach),
DEVMETHOD(device_shutdown, bus_generic_shutdown),
DEVMETHOD(device_suspend, bus_generic_suspend), /* XXX stop statclock? */
DEVMETHOD(device_resume, bus_generic_resume), /* XXX restart statclock? */
{ 0, 0 }
};
static driver_t attimer_driver = {
"attimer",
attimer_methods,
1, /* no softc */
};
static devclass_t attimer_devclass;
DRIVER_MODULE(attimer, isa, attimer_driver, attimer_devclass, 0, 0);
#ifndef PC98
DRIVER_MODULE(attimer, acpi, attimer_driver, attimer_devclass, 0, 0);
#endif
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