OpenCloudOS-Kernel/arch/m32r/kernel/time.c

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/*
* linux/arch/m32r/kernel/time.c
*
* Copyright (c) 2001, 2002 Hiroyuki Kondo, Hirokazu Takata,
* Hitoshi Yamamoto
* Taken from i386 version.
* Copyright (C) 1991, 1992, 1995 Linus Torvalds
* Copyright (C) 1996, 1997, 1998 Ralf Baechle
*
* This file contains the time handling details for PC-style clocks as
* found in some MIPS systems.
*
* Some code taken from sh version.
* Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka
* Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>
*/
#undef DEBUG_TIMER
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/param.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/profile.h>
#include <asm/io.h>
#include <asm/m32r.h>
#include <asm/hw_irq.h>
#ifdef CONFIG_SMP
extern void send_IPI_allbutself(int, int);
extern void smp_local_timer_interrupt(void);
#endif
#define TICK_SIZE (tick_nsec / 1000)
/*
* Change this if you have some constant time drift
*/
/* This is for machines which generate the exact clock. */
#define USECS_PER_JIFFY (1000000/HZ)
static unsigned long latch;
static unsigned long do_gettimeoffset(void)
{
unsigned long elapsed_time = 0; /* [us] */
#if defined(CONFIG_CHIP_M32102) || defined(CONFIG_CHIP_XNUX2) \
|| defined(CONFIG_CHIP_VDEC2) || defined(CONFIG_CHIP_M32700) \
|| defined(CONFIG_CHIP_OPSP) || defined(CONFIG_CHIP_M32104)
#ifndef CONFIG_SMP
unsigned long count;
/* timer count may underflow right here */
count = inl(M32R_MFT2CUT_PORTL);
if (inl(M32R_ICU_CR18_PORTL) & 0x00000100) /* underflow check */
count = 0;
count = (latch - count) * TICK_SIZE;
elapsed_time = (count + latch / 2) / latch;
/* NOTE: LATCH is equal to the "interval" value (= reload count). */
#else /* CONFIG_SMP */
unsigned long count;
static unsigned long p_jiffies = -1;
static unsigned long p_count = 0;
/* timer count may underflow right here */
count = inl(M32R_MFT2CUT_PORTL);
if (jiffies == p_jiffies && count > p_count)
count = 0;
p_jiffies = jiffies;
p_count = count;
count = (latch - count) * TICK_SIZE;
elapsed_time = (count + latch / 2) / latch;
/* NOTE: LATCH is equal to the "interval" value (= reload count). */
#endif /* CONFIG_SMP */
#elif defined(CONFIG_CHIP_M32310)
#warning do_gettimeoffse not implemented
#else
#error no chip configuration
#endif
return elapsed_time;
}
/*
* This version of gettimeofday has near microsecond resolution.
*/
void do_gettimeofday(struct timeval *tv)
{
unsigned long seq;
unsigned long usec, sec;
unsigned long max_ntp_tick = tick_usec - tickadj;
do {
seq = read_seqbegin(&xtime_lock);
usec = do_gettimeoffset();
/*
* If time_adjust is negative then NTP is slowing the clock
* so make sure not to go into next possible interval.
* Better to lose some accuracy than have time go backwards..
*/
[PATCH] kill wall_jiffies With 2.6.18-rc4-mm2, now wall_jiffies will always be the same as jiffies. So we can kill wall_jiffies completely. This is just a cleanup and logically should not change any real behavior except for one thing: RTC updating code in (old) ppc and xtensa use a condition "jiffies - wall_jiffies == 1". This condition is never met so I suppose it is just a bug. I just remove that condition only instead of kill the whole "if" block. [heiko.carstens@de.ibm.com: s390 build fix and cleanup] Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Cc: Andi Kleen <ak@muc.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ian Molton <spyro@f2s.com> Cc: Mikael Starvik <starvik@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Hirokazu Takata <takata.hirokazu@renesas.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp> Cc: Richard Curnow <rc@rc0.org.uk> Cc: William Lee Irwin III <wli@holomorphy.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp> Cc: Chris Zankel <chris@zankel.net> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01 14:28:31 +08:00
if (unlikely(time_adjust < 0))
usec = min(usec, max_ntp_tick);
sec = xtime.tv_sec;
usec += (xtime.tv_nsec / 1000);
} while (read_seqretry(&xtime_lock, seq));
while (usec >= 1000000) {
usec -= 1000000;
sec++;
}
tv->tv_sec = sec;
tv->tv_usec = usec;
}
EXPORT_SYMBOL(do_gettimeofday);
int do_settimeofday(struct timespec *tv)
{
time_t wtm_sec, sec = tv->tv_sec;
long wtm_nsec, nsec = tv->tv_nsec;
if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
return -EINVAL;
write_seqlock_irq(&xtime_lock);
/*
* This is revolting. We need to set "xtime" correctly. However, the
* value in this location is the value at the most recent update of
* wall time. Discover what correction gettimeofday() would have
* made, and then undo it!
*/
nsec -= do_gettimeoffset() * NSEC_PER_USEC;
wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec);
wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec);
set_normalized_timespec(&xtime, sec, nsec);
set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);
ntp_clear();
write_sequnlock_irq(&xtime_lock);
clock_was_set();
return 0;
}
EXPORT_SYMBOL(do_settimeofday);
/*
* In order to set the CMOS clock precisely, set_rtc_mmss has to be
* called 500 ms after the second nowtime has started, because when
* nowtime is written into the registers of the CMOS clock, it will
* jump to the next second precisely 500 ms later. Check the Motorola
* MC146818A or Dallas DS12887 data sheet for details.
*
* BUG: This routine does not handle hour overflow properly; it just
* sets the minutes. Usually you won't notice until after reboot!
*/
static inline int set_rtc_mmss(unsigned long nowtime)
{
return 0;
}
/* last time the cmos clock got updated */
static long last_rtc_update = 0;
/*
* timer_interrupt() needs to keep up the real-time clock,
* as well as call the "do_timer()" routine every clocktick
*/
irqreturn_t timer_interrupt(int irq, void *dev_id)
{
#ifndef CONFIG_SMP
profile_tick(CPU_PROFILING);
#endif
[PATCH] simplify update_times (avoid jiffies/jiffies_64 aliasing problem) Pass ticks to do_timer() and update_times(), and adjust x86_64 and s390 timer interrupt handler with this change. Currently update_times() calculates ticks by "jiffies - wall_jiffies", but callers of do_timer() should know how many ticks to update. Passing ticks get rid of this redundant calculation. Also there are another redundancy pointed out by Martin Schwidefsky. This cleanup make a barrier added by 5aee405c662ca644980c184774277fc6d0769a84 needless. So this patch removes it. As a bonus, this cleanup make wall_jiffies can be removed easily, since now wall_jiffies is always synced with jiffies. (This patch does not really remove wall_jiffies. It would be another cleanup patch) Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: john stultz <johnstul@us.ibm.com> Cc: Andi Kleen <ak@muc.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Acked-by: Russell King <rmk@arm.linux.org.uk> Cc: Ian Molton <spyro@f2s.com> Cc: Mikael Starvik <starvik@axis.com> Acked-by: David Howells <dhowells@redhat.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Hirokazu Takata <takata.hirokazu@renesas.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp> Cc: Richard Curnow <rc@rc0.org.uk> Cc: William Lee Irwin III <wli@holomorphy.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp> Cc: Chris Zankel <chris@zankel.net> Acked-by: "Luck, Tony" <tony.luck@intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 17:00:32 +08:00
do_timer(1);
#ifndef CONFIG_SMP
update_process_times(user_mode(get_irq_regs()));
#endif
/*
* If we have an externally synchronized Linux clock, then update
* CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
* called as close as possible to 500 ms before the new second starts.
*/
write_seqlock(&xtime_lock);
if (ntp_synced()
&& xtime.tv_sec > last_rtc_update + 660
&& (xtime.tv_nsec / 1000) >= 500000 - ((unsigned)TICK_SIZE) / 2
&& (xtime.tv_nsec / 1000) <= 500000 + ((unsigned)TICK_SIZE) / 2)
{
if (set_rtc_mmss(xtime.tv_sec) == 0)
last_rtc_update = xtime.tv_sec;
else /* do it again in 60 s */
last_rtc_update = xtime.tv_sec - 600;
}
write_sequnlock(&xtime_lock);
/* As we return to user mode fire off the other CPU schedulers..
this is basically because we don't yet share IRQ's around.
This message is rigged to be safe on the 386 - basically it's
a hack, so don't look closely for now.. */
#ifdef CONFIG_SMP
smp_local_timer_interrupt();
smp_send_timer();
#endif
return IRQ_HANDLED;
}
struct irqaction irq0 = {
.handler = timer_interrupt,
.flags = IRQF_DISABLED,
.mask = CPU_MASK_NONE,
.name = "MFT2",
};
void __init time_init(void)
{
unsigned int epoch, year, mon, day, hour, min, sec;
sec = min = hour = day = mon = year = 0;
epoch = 0;
year = 23;
mon = 4;
day = 17;
/* Attempt to guess the epoch. This is the same heuristic as in rtc.c
so no stupid things will happen to timekeeping. Who knows, maybe
Ultrix also uses 1952 as epoch ... */
if (year > 10 && year < 44)
epoch = 1980;
else if (year < 96)
epoch = 1952;
year += epoch;
xtime.tv_sec = mktime(year, mon, day, hour, min, sec);
xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
set_normalized_timespec(&wall_to_monotonic,
-xtime.tv_sec, -xtime.tv_nsec);
#if defined(CONFIG_CHIP_M32102) || defined(CONFIG_CHIP_XNUX2) \
|| defined(CONFIG_CHIP_VDEC2) || defined(CONFIG_CHIP_M32700) \
|| defined(CONFIG_CHIP_OPSP) || defined(CONFIG_CHIP_M32104)
/* M32102 MFT setup */
setup_irq(M32R_IRQ_MFT2, &irq0);
{
unsigned long bus_clock;
unsigned short divide;
bus_clock = boot_cpu_data.bus_clock;
divide = boot_cpu_data.timer_divide;
latch = (bus_clock/divide + HZ / 2) / HZ;
printk("Timer start : latch = %ld\n", latch);
outl((M32R_MFTMOD_CC_MASK | M32R_MFTMOD_TCCR \
|M32R_MFTMOD_CSSEL011), M32R_MFT2MOD_PORTL);
outl(latch, M32R_MFT2RLD_PORTL);
outl(latch, M32R_MFT2CUT_PORTL);
outl(0, M32R_MFT2CMPRLD_PORTL);
outl((M32R_MFTCR_MFT2MSK|M32R_MFTCR_MFT2EN), M32R_MFTCR_PORTL);
}
#elif defined(CONFIG_CHIP_M32310)
#warning time_init not implemented
#else
#error no chip configuration
#endif
}