linux_dsm_epyc7002/arch/sh/kernel/time_64.c

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/*
* arch/sh/kernel/time_64.c
*
* Copyright (C) 2000, 2001 Paolo Alberelli
* Copyright (C) 2003 - 2007 Paul Mundt
* Copyright (C) 2003 Richard Curnow
*
* Original TMU/RTC code taken from sh version.
* Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka
* Some code taken from i386 version.
* Copyright (C) 1991, 1992, 1995 Linus Torvalds
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/errno.h>
#include <linux/rwsem.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/time.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/profile.h>
#include <linux/smp.h>
#include <linux/module.h>
#include <linux/bcd.h>
#include <linux/timex.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <cpu/registers.h> /* required by inline __asm__ stmt. */
#include <cpu/irq.h>
#include <asm/addrspace.h>
#include <asm/processor.h>
#include <asm/uaccess.h>
#include <asm/delay.h>
#include <asm/clock.h>
#define TMU_TOCR_INIT 0x00
#define TMU0_TCR_INIT 0x0020
#define TMU_TSTR_INIT 1
#define TMU_TSTR_OFF 0
/* Real Time Clock */
#define RTC_BLOCK_OFF 0x01040000
#define RTC_BASE PHYS_PERIPHERAL_BLOCK + RTC_BLOCK_OFF
#define RTC_RCR1_CIE 0x10 /* Carry Interrupt Enable */
#define RTC_RCR1 (rtc_base + 0x38)
/* Time Management Unit */
#define TMU_BLOCK_OFF 0x01020000
#define TMU_BASE PHYS_PERIPHERAL_BLOCK + TMU_BLOCK_OFF
#define TMU0_BASE tmu_base + 0x8 + (0xc * 0x0)
#define TMU1_BASE tmu_base + 0x8 + (0xc * 0x1)
#define TMU2_BASE tmu_base + 0x8 + (0xc * 0x2)
#define TMU_TOCR tmu_base+0x0 /* Byte access */
#define TMU_TSTR tmu_base+0x4 /* Byte access */
#define TMU0_TCOR TMU0_BASE+0x0 /* Long access */
#define TMU0_TCNT TMU0_BASE+0x4 /* Long access */
#define TMU0_TCR TMU0_BASE+0x8 /* Word access */
#define TICK_SIZE (tick_nsec / 1000)
static unsigned long tmu_base, rtc_base;
unsigned long cprc_base;
/* Variables to allow interpolation of time of day to resolution better than a
* jiffy. */
/* This is effectively protected by xtime_lock */
static unsigned long ctc_last_interrupt;
static unsigned long long usecs_per_jiffy = 1000000/HZ; /* Approximation */
#define CTC_JIFFY_SCALE_SHIFT 40
/* 2**CTC_JIFFY_SCALE_SHIFT / ctc_ticks_per_jiffy */
static unsigned long long scaled_recip_ctc_ticks_per_jiffy;
/* Estimate number of microseconds that have elapsed since the last timer tick,
by scaling the delta that has occurred in the CTC register.
WARNING WARNING WARNING : This algorithm relies on the CTC decrementing at
the CPU clock rate. If the CPU sleeps, the CTC stops counting. Bear this
in mind if enabling SLEEP_WORKS in process.c. In that case, this algorithm
probably needs to use TMU.TCNT0 instead. This will work even if the CPU is
sleeping, though will be coarser.
FIXME : What if usecs_per_tick is moving around too much, e.g. if an adjtime
is running or if the freq or tick arguments of adjtimex are modified after
we have calibrated the scaling factor? This will result in either a jump at
the end of a tick period, or a wrap backwards at the start of the next one,
if the application is reading the time of day often enough. I think we
ought to do better than this. For this reason, usecs_per_jiffy is left
separated out in the calculation below. This allows some future hook into
the adjtime-related stuff in kernel/timer.c to remove this hazard.
*/
static unsigned long usecs_since_tick(void)
{
unsigned long long current_ctc;
long ctc_ticks_since_interrupt;
unsigned long long ull_ctc_ticks_since_interrupt;
unsigned long result;
unsigned long long mul1_out;
unsigned long long mul1_out_high;
unsigned long long mul2_out_low, mul2_out_high;
/* Read CTC register */
asm ("getcon cr62, %0" : "=r" (current_ctc));
/* Note, the CTC counts down on each CPU clock, not up.
Note(2), use long type to get correct wraparound arithmetic when
the counter crosses zero. */
ctc_ticks_since_interrupt = (long) ctc_last_interrupt - (long) current_ctc;
ull_ctc_ticks_since_interrupt = (unsigned long long) ctc_ticks_since_interrupt;
/* Inline assembly to do 32x32x32->64 multiplier */
asm volatile ("mulu.l %1, %2, %0" :
"=r" (mul1_out) :
"r" (ull_ctc_ticks_since_interrupt), "r" (usecs_per_jiffy));
mul1_out_high = mul1_out >> 32;
asm volatile ("mulu.l %1, %2, %0" :
"=r" (mul2_out_low) :
"r" (mul1_out), "r" (scaled_recip_ctc_ticks_per_jiffy));
#if 1
asm volatile ("mulu.l %1, %2, %0" :
"=r" (mul2_out_high) :
"r" (mul1_out_high), "r" (scaled_recip_ctc_ticks_per_jiffy));
#endif
result = (unsigned long) (((mul2_out_high << 32) + mul2_out_low) >> CTC_JIFFY_SCALE_SHIFT);
return result;
}
void do_gettimeofday(struct timeval *tv)
{
unsigned long flags;
unsigned long seq;
unsigned long usec, sec;
do {
seq = read_seqbegin_irqsave(&xtime_lock, flags);
usec = usecs_since_tick();
sec = xtime.tv_sec;
usec += xtime.tv_nsec / 1000;
} while (read_seqretry_irqrestore(&xtime_lock, seq, flags));
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!
*/
[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 13:28:31 +07:00
nsec -= 1000 * usecs_since_tick();
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);
/* Dummy RTC ops */
static void null_rtc_get_time(struct timespec *tv)
{
tv->tv_sec = mktime(2000, 1, 1, 0, 0, 0);
tv->tv_nsec = 0;
}
static int null_rtc_set_time(const time_t secs)
{
return 0;
}
void (*rtc_sh_get_time)(struct timespec *) = null_rtc_get_time;
int (*rtc_sh_set_time)(const time_t) = null_rtc_set_time;
/* last time the RTC clock got updated */
static long last_rtc_update;
/*
* timer_interrupt() needs to keep up the real-time clock,
* as well as call the "do_timer()" routine every clocktick
*/
static inline void do_timer_interrupt(void)
{
unsigned long long current_ctc;
if (current->pid)
profile_tick(CPU_PROFILING);
/*
* Here we are in the timer irq handler. We just have irqs locally
* disabled but we don't know if the timer_bh is running on the other
* CPU. We need to avoid to SMP race with it. NOTE: we don' t need
* the irq version of write_lock because as just said we have irq
* locally disabled. -arca
*/
write_seqlock(&xtime_lock);
asm ("getcon cr62, %0" : "=r" (current_ctc));
ctc_last_interrupt = (unsigned long) current_ctc;
[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 16:00:32 +07:00
do_timer(1);
#ifdef CONFIG_HEARTBEAT
if (sh_mv.mv_heartbeat != NULL)
sh_mv.mv_heartbeat();
#endif
/*
* If we have an externally synchronized Linux clock, then update
* RTC clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
* called as close as possible to 500 ms before the new second starts.
*/
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 (rtc_sh_set_time(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);
#ifndef CONFIG_SMP
update_process_times(user_mode(get_irq_regs()));
#endif
}
/*
* This is the same as the above, except we _also_ save the current
* Time Stamp Counter value at the time of the timer interrupt, so that
* we later on can estimate the time of day more exactly.
*/
static irqreturn_t timer_interrupt(int irq, void *dev_id)
{
unsigned long timer_status;
/* Clear UNF bit */
timer_status = ctrl_inw(TMU0_TCR);
timer_status &= ~0x100;
ctrl_outw(timer_status, TMU0_TCR);
do_timer_interrupt();
return IRQ_HANDLED;
}
static struct irqaction irq0 = {
.handler = timer_interrupt,
.flags = IRQF_DISABLED,
.mask = CPU_MASK_NONE,
.name = "timer",
};
void __init time_init(void)
{
unsigned long interval;
struct clk *clk;
tmu_base = onchip_remap(TMU_BASE, 1024, "TMU");
if (!tmu_base) {
panic("Unable to remap TMU\n");
}
rtc_base = onchip_remap(RTC_BASE, 1024, "RTC");
if (!rtc_base) {
panic("Unable to remap RTC\n");
}
clk = clk_get(NULL, "cpu_clk");
scaled_recip_ctc_ticks_per_jiffy = ((1ULL << CTC_JIFFY_SCALE_SHIFT) /
(unsigned long long)(clk_get_rate(clk) / HZ));
rtc_sh_get_time(&xtime);
setup_irq(TIMER_IRQ, &irq0);
clk = clk_get(NULL, "module_clk");
interval = (clk_get_rate(clk)/(HZ*4));
printk("Interval = %ld\n", interval);
/* Start TMU0 */
ctrl_outb(TMU_TSTR_OFF, TMU_TSTR);
ctrl_outb(TMU_TOCR_INIT, TMU_TOCR);
ctrl_outw(TMU0_TCR_INIT, TMU0_TCR);
ctrl_outl(interval, TMU0_TCOR);
ctrl_outl(interval, TMU0_TCNT);
ctrl_outb(TMU_TSTR_INIT, TMU_TSTR);
}
static struct resource rtc_resources[] = {
[0] = {
/* RTC base, filled in by rtc_init */
.flags = IORESOURCE_IO,
},
[1] = {
/* Period IRQ */
.start = IRQ_PRI,
.flags = IORESOURCE_IRQ,
},
[2] = {
/* Carry IRQ */
.start = IRQ_CUI,
.flags = IORESOURCE_IRQ,
},
[3] = {
/* Alarm IRQ */
.start = IRQ_ATI,
.flags = IORESOURCE_IRQ,
},
};
static struct platform_device rtc_device = {
.name = "sh-rtc",
.id = -1,
.num_resources = ARRAY_SIZE(rtc_resources),
.resource = rtc_resources,
};
static int __init rtc_init(void)
{
rtc_resources[0].start = rtc_base;
rtc_resources[0].end = rtc_resources[0].start + 0x58 - 1;
return platform_device_register(&rtc_device);
}
device_initcall(rtc_init);