1
0
mirror of https://git.FreeBSD.org/src.git synced 2024-12-24 11:29:10 +00:00
freebsd/sys/pc98/cbus/clock.c
Bruce Evans cec54a8d96 Oops, pc98 is independent of i386 for clock.c and machdep.c but not
for clock.h, so changing th i386 clock.h broke it.  MFi386 (not tested):

Cleaned up declaration and initialization of clock_lock.  It is only
used by clock code, so don't export it to the world for machdep.c to
initialize.  There is a minor problem initializing it before it is
used, since although clock initialization is split up so that parts
of it can be done early, the first part was never done early enough
to actually work.  Split it up a bit more and do the first part as
late as possible to document the necessary order.  The functions that
implement the split are still bogusly exported.

Cleaned up initialization of the i8254 clock hardware using the new
split.  Actually initialize it early enough, and don't work around it
not being initialized in DELAY() when DELAY() is called early for
initialization of some console drivers.

This unfortunately moves a little more code before the early debugger
breakpoint so that it is harder to debug.  The ordering of console and
related initialization is delicate because we want to do as little as
possible before the breakpoint, but must initialize a console.
2007-01-23 08:48:26 +00:00

832 lines
19 KiB
C

/*-
* 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.
* 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_apic.h"
#include "opt_clock.h"
#include "opt_isa.h"
#include "opt_mca.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/clock.h>
#include <sys/lock.h>
#include <sys/kdb.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/time.h>
#include <sys/timetc.h>
#include <sys/kernel.h>
#include <sys/limits.h>
#include <sys/module.h>
#include <sys/sysctl.h>
#include <sys/cons.h>
#include <sys/power.h>
#include <machine/clock.h>
#include <machine/cpu.h>
#include <machine/cputypes.h>
#include <machine/frame.h>
#include <machine/intr_machdep.h>
#include <machine/md_var.h>
#include <machine/psl.h>
#ifdef DEV_APIC
#include <machine/apicvar.h>
#endif
#include <machine/specialreg.h>
#include <machine/ppireg.h>
#include <machine/timerreg.h>
#include <i386/isa/icu.h>
#include <pc98/cbus/cbus.h>
#include <pc98/pc98/pc98_machdep.h>
#ifdef DEV_ISA
#include <isa/isavar.h>
#endif
#define TIMER_DIV(x) ((timer_freq + (x) / 2) / (x))
int clkintr_pending;
int pscnt = 1;
int psdiv = 1;
int statclock_disable;
#ifndef TIMER_FREQ
#define TIMER_FREQ 2457600
#endif
u_int timer_freq = TIMER_FREQ;
int timer0_max_count;
int timer0_real_max_count;
struct mtx clock_lock;
static int beeping = 0;
static struct intsrc *i8254_intsrc;
static u_int32_t i8254_lastcount;
static u_int32_t i8254_offset;
static int (*i8254_pending)(struct intsrc *);
static int i8254_ticked;
static int using_lapic_timer;
/* Values for timerX_state: */
#define RELEASED 0
#define RELEASE_PENDING 1
#define ACQUIRED 2
#define ACQUIRE_PENDING 3
static u_char timer1_state;
static u_char timer2_state;
static void rtc_serialcombit(int);
static void rtc_serialcom(int);
static int rtc_inb(void);
static void rtc_outb(int);
static unsigned i8254_get_timecount(struct timecounter *tc);
static unsigned i8254_simple_get_timecount(struct timecounter *tc);
static void set_timer_freq(u_int freq, int intr_freq);
static struct timecounter i8254_timecounter = {
i8254_get_timecount, /* get_timecount */
0, /* no poll_pps */
~0u, /* counter_mask */
0, /* frequency */
"i8254", /* name */
0 /* quality */
};
static void
clkintr(struct trapframe *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);
}
KASSERT(!using_lapic_timer, ("clk interrupt enabled with lapic timer"));
hardclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
}
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);
}
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_timer1()
{
if (timer1_state != ACQUIRED)
return (-1);
timer1_state = RELEASED;
outb(TIMER_MODE, TIMER_SEL1 | TIMER_SQWAVE | TIMER_16BIT);
return (0);
}
int
release_timer2()
{
if (timer2_state != ACQUIRED)
return (-1);
timer2_state = RELEASED;
outb(TIMER_MODE, TIMER_SEL2 | TIMER_SQWAVE | TIMER_16BIT);
return (0);
}
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
/*
* 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).
*
* However, if ddb is active then use a fake counter since reading
* the i8254 counter involves acquiring a lock. ddb must not do
* locking for many reasons, but it calls here for at least atkbd
* input.
*/
#ifdef KDB
if (kdb_active)
prev_tick = 1;
else
#endif
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) {
#ifdef KDB
if (kdb_active) {
outb(0x5f, 0);
tick = prev_tick - 1;
if (tick <= 0)
tick = timer0_max_count;
} else
#endif
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)
{
ppi_spkr_off(); /* disable counter1 output to speaker */
timer_spkr_release();
beeping = 0;
}
int
sysbeep(int pitch, int period)
{
int x = splclock();
if (timer_spkr_acquire())
if (!beeping) {
/* Something else owns it. */
splx(x);
return (-1); /* XXX Should be EBUSY, but nobody cares anyway. */
}
disable_intr();
spkr_set_pitch(pitch);
enable_intr();
if (!beeping) {
/* enable counter1 output to speaker */
ppi_spkr_on();
beeping = period;
timeout(sysbeepstop, (void *)NULL, period);
}
splx(x);
return (0);
}
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);
}
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;
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) || /* 1200 = 307.2KHz >> 8 */
(sec < start_sec &&
(u_int)sec + 0x10000 == (u_int)start_sec + 1200))
break;
if (--timeout == 0)
goto fail;
}
if (bootverbose) {
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);
}
static void
set_timer_freq(u_int freq, int intr_freq)
{
int new_timer0_real_max_count;
i8254_timecounter.tc_frequency = freq;
mtx_lock_spin(&clock_lock);
timer_freq = freq;
if (using_lapic_timer)
new_timer0_real_max_count = 0x10000;
else
new_timer0_real_max_count = TIMER_DIV(intr_freq);
if (new_timer0_real_max_count != timer0_real_max_count) {
timer0_real_max_count = new_timer0_real_max_count;
if (timer0_real_max_count == 0x10000)
timer0_max_count = 0xffff;
else
timer0_max_count = timer0_real_max_count;
outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
outb(TIMER_CNTR0, timer0_real_max_count & 0xff);
outb(TIMER_CNTR0, timer0_real_max_count >> 8);
}
mtx_unlock_spin(&clock_lock);
}
static void
i8254_restore(void)
{
mtx_lock_spin(&clock_lock);
outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
outb(TIMER_CNTR0, timer0_real_max_count & 0xff);
outb(TIMER_CNTR0, timer0_real_max_count >> 8);
mtx_unlock_spin(&clock_lock);
}
/*
* Restore all the timers non-atomically (XXX: should be atomically).
*
* This function is called from pmtimer_resume() to restore all the timers.
* This should not be necessary, but there are broken laptops that do not
* restore all the timers on resume.
*/
void
timer_restore(void)
{
i8254_restore(); /* restore timer_freq and hz */
}
/* This is separate from startrtclock() so that it can be called early. */
void
i8254_init(void)
{
mtx_init(&clock_lock, "clk", NULL, MTX_SPIN | MTX_NOPROFILE);
set_timer_freq(timer_freq, hz);
}
void
startrtclock()
{
u_int delta, freq;
findcpuspeed();
if (pc98_machine_type & M_8M)
timer_freq = 1996800L; /* 1.9968 MHz */
else
timer_freq = 2457600L; /* 2.4576 MHz */
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);
}
set_timer_freq(timer_freq, hz);
tc_init(&i8254_timecounter);
init_TSC();
}
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;
}
/*
* Initialize the time of day register, based on the time base which is, e.g.
* from a filesystem.
*/
void
inittodr(time_t base)
{
struct timespec ts;
struct clocktime ct;
if (base) {
ts.tv_sec = base;
ts.tv_nsec = 0;
tc_setclock(&ts);
}
rtc_serialcom(0x03); /* Time Read */
rtc_serialcom(0x01); /* Register shift command. */
DELAY(20);
ct.nsec = 0;
ct.sec = bcd2bin(rtc_inb() & 0xff); /* sec */
ct.min = bcd2bin(rtc_inb() & 0xff); /* min */
ct.hour = bcd2bin(rtc_inb() & 0xff); /* hour */
ct.day = bcd2bin(rtc_inb() & 0xff) - 1; /* date */
ct.mon = (rtc_inb() >> 4) & 0x0f; /* month */
ct.year = bcd2bin(rtc_inb() & 0xff) + 1900; /* year */
if (ct.year < 1995)
ct.year += 100;
clock_ct_to_ts(&ct, &ts);
tc_setclock(&ts);
}
/*
* Write system time back to RTC
*/
void
resettodr()
{
struct timespec ts;
struct clocktime ct;
if (disable_rtc_set)
return;
getnanotime(&ts);
ts.tv_sec -= utc_offset();
clock_ts_to_ct(&ts, &ct);
rtc_serialcom(0x01); /* Register shift command. */
rtc_outb(bin2bcd(ct.sec)); /* Write back Seconds */
rtc_outb(bin2bcd(ct.min)); /* Write back Minutes */
rtc_outb(bin2bcd(ct.hour)); /* Write back Hours */
rtc_outb(bin2bcd(ct.day)); /* Write back Day */
rtc_outb((ct.mon << 4) | (ct.dow + 1)); /* Write back Month and DOW */
rtc_outb(bin2bcd(ct.year % 100)); /* Write back Year */
rtc_serialcom(0x02); /* Time set & Counter hold command. */
rtc_serialcom(0x00); /* Register hold command. */
}
/*
* Start both clocks running.
*/
void
cpu_initclocks()
{
#ifdef DEV_APIC
using_lapic_timer = lapic_setup_clock();
#endif
/*
* If we aren't using the local APIC timer to drive the kernel
* clocks, setup the interrupt handler for the 8254 timer 0 so
* that it can drive hardclock(). Otherwise, change the 8254
* timecounter to user a simpler algorithm.
*/
if (!using_lapic_timer) {
intr_add_handler("clk", 0, (driver_intr_t *)clkintr, NULL,
INTR_TYPE_CLK | INTR_FAST, NULL);
i8254_intsrc = intr_lookup_source(0);
if (i8254_intsrc != NULL)
i8254_pending =
i8254_intsrc->is_pic->pic_source_pending;
} else {
i8254_timecounter.tc_get_timecount =
i8254_simple_get_timecount;
i8254_timecounter.tc_counter_mask = 0xffff;
set_timer_freq(timer_freq, hz);
}
init_TSC_tc();
}
void
cpu_startprofclock(void)
{
}
void
cpu_stopprofclock(void)
{
}
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)
set_timer_freq(freq, hz);
return (error);
}
SYSCTL_PROC(_machdep, OID_AUTO, i8254_freq, CTLTYPE_INT | CTLFLAG_RW,
0, sizeof(u_int), sysctl_machdep_i8254_freq, "IU", "");
static unsigned
i8254_simple_get_timecount(struct timecounter *tc)
{
return (timer0_max_count - getit());
}
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)) &&
i8254_pending != NULL && i8254_pending(i8254_intsrc))))) {
i8254_ticked = 1;
i8254_offset += timer0_max_count;
}
i8254_lastcount = count;
count += i8254_offset;
mtx_unlock_spin(&clock_lock);
return (count);
}
#ifdef DEV_ISA
/*
* 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);
#endif /* DEV_ISA */