MN10300: Generic time support
Implement generic time support for MN10300.
Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
diff --git a/arch/mn10300/kernel/time.c b/arch/mn10300/kernel/time.c
index 0cb9bdb..f860a34 100644
--- a/arch/mn10300/kernel/time.c
+++ b/arch/mn10300/kernel/time.c
@@ -17,6 +17,8 @@
#include <linux/smp.h>
#include <linux/profile.h>
#include <linux/cnt32_to_63.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
#include <asm/irq.h>
#include <asm/div64.h>
#include <asm/processor.h>
@@ -27,14 +29,6 @@
static unsigned long mn10300_last_tsc; /* time-stamp counter at last time
* interrupt occurred */
-static irqreturn_t timer_interrupt(int irq, void *dev_id);
-
-static struct irqaction timer_irq = {
- .handler = timer_interrupt,
- .flags = IRQF_DISABLED | IRQF_SHARED | IRQF_TIMER,
- .name = "timer",
-};
-
static unsigned long sched_clock_multiplier;
/*
@@ -54,7 +48,7 @@
/* read the TSC value
*/
- tsc = 0 - get_cycles(); /* get_cycles() counts down */
+ tsc = get_cycles();
/* expand to 64-bits.
* - sched_clock() must be called once a minute or better or the
@@ -103,6 +97,7 @@
return IRQ_HANDLED;
}
+#ifndef CONFIG_GENERIC_TIME
/*
* advance the kernel's time keeping clocks (xtime and jiffies)
* - we use Timer 0 & 1 cascaded as a clock to nudge us the next time
@@ -116,11 +111,11 @@
write_seqlock(&xtime_lock);
while (tsc = get_cycles(),
- elapse = mn10300_last_tsc - tsc, /* time elapsed since last
+ elapse = tsc - mn10300_last_tsc, /* time elapsed since last
* tick */
elapse > MN10300_TSC_PER_HZ
) {
- mn10300_last_tsc -= MN10300_TSC_PER_HZ;
+ mn10300_last_tsc += MN10300_TSC_PER_HZ;
/* advance the kernel's time tracking system */
do_timer(1);
@@ -135,6 +130,50 @@
return ret;
}
+static struct irqaction timer_irq = {
+ .handler = timer_interrupt,
+ .flags = IRQF_DISABLED | IRQF_SHARED | IRQF_TIMER,
+ .name = "timer",
+};
+#endif /* CONFIG_GENERIC_TIME */
+
+#ifdef CONFIG_CSRC_MN10300
+void __init clocksource_set_clock(struct clocksource *cs, unsigned int clock)
+{
+ u64 temp;
+ u32 shift;
+
+ /* Find a shift value */
+ for (shift = 32; shift > 0; shift--) {
+ temp = (u64) NSEC_PER_SEC << shift;
+ do_div(temp, clock);
+ if ((temp >> 32) == 0)
+ break;
+ }
+ cs->shift = shift;
+ cs->mult = (u32) temp;
+}
+#endif
+
+#if CONFIG_CEVT_MN10300
+void __cpuinit clockevent_set_clock(struct clock_event_device *cd,
+ unsigned int clock)
+{
+ u64 temp;
+ u32 shift;
+
+ /* Find a shift value */
+ for (shift = 32; shift > 0; shift--) {
+ temp = (u64) clock << shift;
+ do_div(temp, NSEC_PER_SEC);
+ if ((temp >> 32) == 0)
+ break;
+ }
+ cd->shift = shift;
+ cd->mult = (u32) temp;
+}
+#endif
+
/*
* initialise the various timers used by the main part of the kernel
*/
@@ -146,21 +185,25 @@
*/
TMPSCNT |= TMPSCNT_ENABLE;
+#ifdef CONFIG_GENERIC_TIME
+ init_clocksource();
+#else
startup_timestamp_counter();
+#endif
printk(KERN_INFO
"timestamp counter I/O clock running at %lu.%02lu"
" (calibrated against RTC)\n",
MN10300_TSCCLK / 1000000, (MN10300_TSCCLK / 10000) % 100);
- mn10300_last_tsc = TMTSCBC;
+ mn10300_last_tsc = read_timestamp_counter();
- /* use timer 0 & 1 cascaded to tick at as close to HZ as possible */
- setup_irq(TMJCIRQ, &timer_irq);
-
- set_intr_level(TMJCIRQ, NUM2GxICR_LEVEL(CONFIG_TIMER_IRQ_LEVEL));
-
- startup_jiffies_counter();
+#ifdef CONFIG_GENERIC_CLOCKEVENTS
+ init_clockevents();
+#else
+ reload_jiffies_counter(MN10300_JC_PER_HZ - 1);
+ setup_jiffies_interrupt(TMJCIRQ, &timer_irq, CONFIG_TIMER_IRQ_LEVEL);
+#endif
#ifdef CONFIG_MN10300_WD_TIMER
/* start the watchdog timer */