android_kernel_xiaomi_sm8350/arch/ia64/sn/kernel/sn2/timer.c
Magnus Damm 8e19608e8b clocksource: pass clocksource to read() callback
Pass clocksource pointer to the read() callback for clocksources.  This
allows us to share the callback between multiple instances.

[hugh@veritas.com: fix powerpc build of clocksource pass clocksource mods]
[akpm@linux-foundation.org: cleanup]
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-21 13:41:47 -07:00

66 lines
1.6 KiB
C

/*
* linux/arch/ia64/sn/kernel/sn2/timer.c
*
* Copyright (C) 2003 Silicon Graphics, Inc.
* Copyright (C) 2003 Hewlett-Packard Co
* David Mosberger <davidm@hpl.hp.com>: updated for new timer-interpolation infrastructure
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/time.h>
#include <linux/interrupt.h>
#include <linux/clocksource.h>
#include <asm/hw_irq.h>
#include <asm/system.h>
#include <asm/timex.h>
#include <asm/sn/leds.h>
#include <asm/sn/shub_mmr.h>
#include <asm/sn/clksupport.h>
extern unsigned long sn_rtc_cycles_per_second;
static cycle_t read_sn2(struct clocksource *cs)
{
return (cycle_t)readq(RTC_COUNTER_ADDR);
}
static struct clocksource clocksource_sn2 = {
.name = "sn2_rtc",
.rating = 450,
.read = read_sn2,
.mask = (1LL << 55) - 1,
.mult = 0,
.shift = 10,
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
/*
* sn udelay uses the RTC instead of the ITC because the ITC is not
* synchronized across all CPUs, and the thread may migrate to another CPU
* if preemption is enabled.
*/
static void
ia64_sn_udelay (unsigned long usecs)
{
unsigned long start = rtc_time();
unsigned long end = start +
usecs * sn_rtc_cycles_per_second / 1000000;
while (time_before((unsigned long)rtc_time(), end))
cpu_relax();
}
void __init sn_timer_init(void)
{
clocksource_sn2.fsys_mmio = RTC_COUNTER_ADDR;
clocksource_sn2.mult = clocksource_hz2mult(sn_rtc_cycles_per_second,
clocksource_sn2.shift);
clocksource_register(&clocksource_sn2);
ia64_udelay = &ia64_sn_udelay;
}