NetBSD/sys/arch/macppc/macppc/clock.c

291 lines
6.4 KiB
C

/* $NetBSD: clock.c,v 1.13 2000/08/20 07:48:45 tsubai Exp $ */
/*
* Copyright (C) 1995, 1996 Wolfgang Solfrank.
* Copyright (C) 1995, 1996 TooLs GmbH.
* All rights reserved.
*
* 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 TooLs GmbH.
* 4. The name of TooLs GmbH may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``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 TOOLS GMBH 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.
*/
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <uvm/uvm_extern.h>
#include <dev/ofw/openfirm.h>
#include <machine/cpu.h>
#include "adb.h"
/*
* Initially we assume a processor with a bus frequency of 50 MHz.
*/
static u_long ticks_per_sec = 50*1000*1000/4;
static u_long ns_per_tick = 80;
static long ticks_per_intr;
static volatile u_long lasttb;
#ifdef TIMEBASE_FREQ
u_int timebase_freq = TIMEBASE_FREQ;
#else
u_int timebase_freq = 0;
#endif
#define SECDAY 86400
#define DIFF19041970 2082844800
#if NADB > 0
extern int adb_read_date_time __P((int *));
extern int adb_set_date_time __P((int));
#endif
static int clockinitted = 0;
void
inittodr(base)
time_t base;
{
time_t deltat;
u_int rtc_time;
/*
* If we can't read from RTC, use the fs time.
*/
#if NADB > 0
if (adb_read_date_time(&rtc_time) < 0)
#endif
{
time.tv_sec = base;
return;
}
clockinitted = 1;
time.tv_sec = rtc_time - DIFF19041970;
deltat = time.tv_sec - base;
if (deltat < 0)
deltat = -deltat;
if (deltat < 2 * SECDAY)
return;
printf("WARNING: clock %s %d days",
time.tv_sec < base ? "lost" : "gained", (int)(deltat / SECDAY));
printf(" -- CHECK AND RESET THE DATE!\n");
}
/*
* Similar to the above
*/
void
resettodr()
{
#if NADB > 0
u_int rtc_time;
if (clockinitted) {
rtc_time = time.tv_sec + DIFF19041970;
adb_set_date_time(rtc_time);
}
#endif
}
void
decr_intr(frame)
struct clockframe *frame;
{
u_long tb;
long tick;
int nticks;
int pri, msr;
/*
* Check whether we are initialized.
*/
if (!ticks_per_intr)
return;
/*
* Based on the actual time delay since the last decrementer reload,
* we arrange for earlier interrupt next time.
*/
asm ("mfdec %0" : "=r"(tick));
for (nticks = 0; tick < 0; nticks++)
tick += ticks_per_intr;
asm volatile ("mtdec %0" :: "r"(tick));
uvmexp.intrs++;
intrcnt[CNT_CLOCK]++;
pri = splclock();
if (pri & (1 << SPL_CLOCK))
tickspending += nticks;
else {
nticks += tickspending;
tickspending = 0;
/*
* lasttb is used during microtime. Set it to the virtual
* start of this tick interval.
*/
asm ("mftb %0" : "=r"(tb));
lasttb = tb + tick - ticks_per_intr;
/*
* Reenable interrupts
*/
asm volatile ("mfmsr %0; ori %0, %0, %1; mtmsr %0"
: "=r"(msr) : "K"(PSL_EE));
/*
* Do standard timer interrupt stuff.
* Do softclock stuff only on the last iteration.
*/
frame->pri = pri | (1 << SIR_CLOCK);
while (--nticks > 0)
hardclock(frame);
frame->pri = pri;
hardclock(frame);
}
splx(pri);
}
void
cpu_initclocks()
{
}
void
calc_delayconst()
{
int qhandle, phandle;
char type[32];
int msr, scratch;
/*
* Get this info during autoconf? XXX
*/
if (timebase_freq != 0) {
ticks_per_sec = timebase_freq;
goto found;
}
for (qhandle = OF_peer(0); qhandle; qhandle = phandle) {
if (OF_getprop(qhandle, "device_type", type, sizeof type) > 0
&& strcmp(type, "cpu") == 0
&& OF_getprop(qhandle, "timebase-frequency",
&ticks_per_sec, sizeof ticks_per_sec) > 0) {
goto found;
}
if ((phandle = OF_child(qhandle)))
continue;
while (qhandle) {
if ((phandle = OF_peer(qhandle)))
break;
qhandle = OF_parent(qhandle);
}
}
panic("no cpu node");
found:
/*
* Should check for correct CPU here? XXX
*/
asm volatile ("mfmsr %0; andi. %1,%0,%2; mtmsr %1"
: "=r"(msr), "=r"(scratch) : "K"((u_short)~PSL_EE));
ns_per_tick = 1000000000 / ticks_per_sec;
ticks_per_intr = ticks_per_sec / hz;
asm volatile ("mftb %0" : "=r"(lasttb));
asm volatile ("mtdec %0" :: "r"(ticks_per_intr));
asm volatile ("mtmsr %0" :: "r"(msr));
}
static inline u_quad_t
mftb()
{
u_long scratch;
u_quad_t tb;
asm ("1: mftbu %0; mftb %0+1; mftbu %1; cmpw 0,%0,%1; bne 1b"
: "=r"(tb), "=r"(scratch));
return tb;
}
/*
* Fill in *tvp with current time with microsecond resolution.
*/
void
microtime(tvp)
struct timeval *tvp;
{
u_long tb;
u_long ticks;
int msr, scratch;
asm volatile ("mfmsr %0; andi. %1,%0,%2; mtmsr %1"
: "=r"(msr), "=r"(scratch) : "K"((u_short)~PSL_EE));
asm ("mftb %0" : "=r"(tb));
ticks = (tb - lasttb) * ns_per_tick;
*tvp = time;
asm volatile ("mtmsr %0" :: "r"(msr));
ticks /= 1000;
tvp->tv_usec += ticks;
while (tvp->tv_usec >= 1000000) {
tvp->tv_usec -= 1000000;
tvp->tv_sec++;
}
}
/*
* Wait for about n microseconds (at least!).
*/
void
delay(n)
unsigned n;
{
u_quad_t tb;
u_long tbh, tbl, scratch;
tb = mftb();
tb += (n * 1000 + ns_per_tick - 1) / ns_per_tick;
tbh = tb >> 32;
tbl = tb;
asm volatile ("1: mftbu %0; cmplw %0,%1; blt 1b; bgt 2f;"
"mftb %0; cmplw %0,%2; blt 1b; 2:"
: "=r"(scratch) : "r"(tbh), "r"(tbl));
}
/*
* Nothing to do.
*/
void
setstatclockrate(arg)
int arg;
{
/* Do nothing */
}