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authorRussell King <rmk+kernel@arm.linux.org.uk>2010-12-16 00:55:06 +0300
committerRussell King <rmk+kernel@arm.linux.org.uk>2010-12-23 01:44:49 +0300
commitf06a1624621527ef597ae4b3b795553fc1b2eff2 (patch)
treebceabde5032fc27d71d6da436e74c7f848022825 /arch/arm/plat-orion
parentdc548fbbd2ecd0fc3b02301d551e5f8e19ae58fd (diff)
downloadlinux-f06a1624621527ef597ae4b3b795553fc1b2eff2.tar.xz
ARM: orion: convert sched_clock() to use new infrastructure
Convert orion platforms to use the new sched_clock() infrastructure for extending 32bit counters to full 64-bit nanoseconds. Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/plat-orion')
-rw-r--r--arch/arm/plat-orion/time.c44
1 files changed, 9 insertions, 35 deletions
diff --git a/arch/arm/plat-orion/time.c b/arch/arm/plat-orion/time.c
index 123f96f4194f..c3da2478b2aa 100644
--- a/arch/arm/plat-orion/time.c
+++ b/arch/arm/plat-orion/time.c
@@ -13,11 +13,11 @@
#include <linux/kernel.h>
#include <linux/sched.h>
-#include <linux/cnt32_to_63.h>
#include <linux/timer.h>
#include <linux/clockchips.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
+#include <asm/sched_clock.h>
#include <asm/mach/time.h>
#include <mach/bridge-regs.h>
#include <mach/hardware.h>
@@ -44,52 +44,26 @@ static u32 ticks_per_jiffy;
/*
* Orion's sched_clock implementation. It has a resolution of
- * at least 7.5ns (133MHz TCLK) and a maximum value of 834 days.
- *
- * Because the hardware timer period is quite short (21 secs if
- * 200MHz TCLK) and because cnt32_to_63() needs to be called at
- * least once per half period to work properly, a kernel timer is
- * set up to ensure this requirement is always met.
+ * at least 7.5ns (133MHz TCLK).
*/
-#define TCLK2NS_SCALE_FACTOR 8
-
-static unsigned long tclk2ns_scale;
+static DEFINE_CLOCK_DATA(cd);
unsigned long long notrace sched_clock(void)
{
- unsigned long long v = cnt32_to_63(0xffffffff - readl(TIMER0_VAL));
- return (v * tclk2ns_scale) >> TCLK2NS_SCALE_FACTOR;
+ u32 cyc = 0xffffffff - readl(TIMER0_VAL);
+ return cyc_to_sched_clock(&cd, cyc, (u32)~0);
}
-static struct timer_list cnt32_to_63_keepwarm_timer;
-static void cnt32_to_63_keepwarm(unsigned long data)
+static void notrace orion_update_sched_clock(void)
{
- mod_timer(&cnt32_to_63_keepwarm_timer, round_jiffies(jiffies + data));
- (void) sched_clock();
+ u32 cyc = 0xffffffff - readl(TIMER0_VAL);
+ update_sched_clock(&cd, cyc, (u32)~0);
}
static void __init setup_sched_clock(unsigned long tclk)
{
- unsigned long long v;
- unsigned long data;
-
- v = NSEC_PER_SEC;
- v <<= TCLK2NS_SCALE_FACTOR;
- v += tclk/2;
- do_div(v, tclk);
- /*
- * We want an even value to automatically clear the top bit
- * returned by cnt32_to_63() without an additional run time
- * instruction. So if the LSB is 1 then round it up.
- */
- if (v & 1)
- v++;
- tclk2ns_scale = v;
-
- data = (0xffffffffUL / tclk / 2 - 2) * HZ;
- setup_timer(&cnt32_to_63_keepwarm_timer, cnt32_to_63_keepwarm, data);
- mod_timer(&cnt32_to_63_keepwarm_timer, round_jiffies(jiffies + data));
+ init_sched_clock(&cd, orion_update_sched_clock, 32, tclk);
}
/*