freebsd-skq/sys/powerpc/aim/clock.c
Peter Grehan 2058844493 Split decr_init() into two, with the section that reads the timebase
frequency from OpenFirmware moved out and into a routine that is called
from cpu_startup().

This allows correct reporting of the CPU clockspeed when printing out
CPU information at boot time.

Reported by:	numerous
Reviewed by:	marcel
MFC after:	1 day
2007-11-13 15:47:55 +00:00

319 lines
7.5 KiB
C

/*-
* 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.
*
* $NetBSD: clock.c,v 1.9 2000/01/19 02:52:19 msaitoh Exp $
*/
/*
* Copyright (C) 2001 Benno Rice.
* 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.
*
* THIS SOFTWARE IS PROVIDED BY Benno Rice ``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/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/bus.h>
#include <sys/clock.h>
#include <sys/timetc.h>
#include <sys/interrupt.h>
#include <dev/ofw/openfirm.h>
#include <machine/clock.h>
#include <machine/cpu.h>
#include <machine/intr.h>
#include <machine/md_var.h>
/*
* Initially we assume a processor with a bus frequency of 12.5 MHz.
*/
u_int tickspending;
u_long ns_per_tick = 80;
static u_long ticks_per_sec = 12500000;
static long ticks_per_intr;
static volatile u_long lasttb;
#define DIFF19041970 2082844800
static int clockinitted = 0;
static timecounter_get_t decr_get_timecount;
static struct timecounter decr_timecounter = {
decr_get_timecount, /* get_timecount */
0, /* no poll_pps */
~0u, /* counter_mask */
0, /* frequency */
"decrementer" /* name */
};
void
inittodr(time_t base)
{
time_t deltat;
u_int rtc_time;
struct timespec ts;
phandle_t phandle;
ihandle_t ihandle;
char rtcpath[128];
u_int rtcsecs;
/*
* If we can't read from RTC, use the fs time.
*/
phandle = OF_finddevice("rtc");
if (phandle != -1) {
OF_package_to_path(phandle, rtcpath, sizeof(rtcpath));
ihandle = OF_open(rtcpath);
if (ihandle != -1) {
if (OF_call_method("read-rtc", ihandle,
0, 1, &rtcsecs))
printf("RTC call method error\n");
else {
ts.tv_sec = rtcsecs - DIFF19041970;
ts.tv_nsec = 0;
tc_setclock(&ts);
return;
}
}
}
{
ts.tv_sec = base;
ts.tv_nsec = 0;
tc_setclock(&ts);
return;
}
clockinitted = 1;
ts.tv_sec = rtc_time - DIFF19041970;
deltat = ts.tv_sec - base;
if (deltat < 0) {
deltat = -deltat;
}
if (deltat < 2 * SECDAY) {
tc_setclock(&ts);
return;
}
printf("WARNING: clock %s %d days",
ts.tv_sec < base ? "lost" : "gained", (int)(deltat / SECDAY));
printf(" -- CHECK AND RESET THE DATE!\n");
}
/*
* Similar to the above
*/
void
resettodr()
{
}
void
decr_intr(struct trapframe *frame)
{
u_long tb;
long tick;
int nticks;
/*
* 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 ("mftb %0; mfdec %1" : "=r"(tb), "=r"(tick));
for (nticks = 0; tick < 0; nticks++)
tick += ticks_per_intr;
mtdec(tick);
/*
* lasttb is used during microtime. Set it to the virtual
* start of this tick interval.
*/
lasttb = tb + tick - ticks_per_intr;
nticks += tickspending;
tickspending = 0;
/*
* Reenable interrupts
*/
#if 0
msr = mfmsr();
mtmsr(msr | PSL_EE | PSL_RI);
#endif
/*
* Do standard timer interrupt stuff.
* Do softclock stuff only on the last iteration.
*/
#if 0
while (--nticks > 0) {
hardclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
}
#endif
hardclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
}
void
decr_init(void)
{
int qhandle, phandle;
char name[32];
unsigned int msr;
phandle = 0;
/*
* Get this info during autoconf? XXX
*/
for (qhandle = OF_peer(0); qhandle; qhandle = phandle) {
if (OF_getprop(qhandle, "device_type", name, sizeof name) >= 0
&& !strcmp(name, "cpu")
&& OF_getprop(qhandle, "timebase-frequency",
&ticks_per_sec, sizeof ticks_per_sec) >= 0) {
/*
* Should check for correct CPU here? XXX
*/
msr = mfmsr();
mtmsr(msr & ~(PSL_EE|PSL_RI));
ns_per_tick = 1000000000 / ticks_per_sec;
ticks_per_intr = ticks_per_sec / hz;
__asm __volatile ("mftb %0" : "=r"(lasttb));
mtdec(ticks_per_intr);
mtmsr(msr);
break;
}
if ((phandle = OF_child(qhandle)))
continue;
while (qhandle) {
if ((phandle = OF_peer(qhandle)))
break;
qhandle = OF_parent(qhandle);
}
}
if (!phandle)
panic("no cpu node");
}
void
decr_tc_init(void)
{
decr_timecounter.tc_frequency = ticks_per_sec;
tc_init(&decr_timecounter);
}
static __inline u_quad_t
mftb(void)
{
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;
}
static unsigned
decr_get_timecount(struct timecounter *tc)
{
return mftb();
}
/*
* Wait for about n microseconds (at least!).
*/
void
DELAY(int n)
{
u_quad_t tb, ttb;
tb = mftb();
ttb = tb + (n * 1000 + ns_per_tick - 1) / ns_per_tick;
while (tb < ttb)
tb = mftb();
}
/*
* Nothing to do.
*/
void
cpu_startprofclock(void)
{
/* Do nothing */
}
void
cpu_stopprofclock(void)
{
}
/*
* XXX Needed by syscons
*/
int
sysbeep(int pitch, int period)
{
return (0);
}