From: Changhwan Youn <chaos.youn@xxxxxxxxxxx>
EXYNOS SOC series use MCT for kernel timer and MCT has two types of
clock event timers, which are mct-comp and mct-tick.
Because the clock rate of each event timer is diffent from the other,
this patch fixes cycles_per_jiffy for each timer's periodic mode.
Signed-off-by: Changhwan Youn <chaos.youn@xxxxxxxxxxx>
Signed-off-by: Kukjin Kim <kgene.kim@xxxxxxxxxxx>
---
arch/arm/mach-exynos/mct.c | 21 +++++++++++++--------
1 files changed, 13 insertions(+), 8 deletions(-)
diff --git a/arch/arm/mach-exynos/mct.c b/arch/arm/mach-exynos/mct.c
index 85b5527..3e894ba 100644
--- a/arch/arm/mach-exynos/mct.c
+++ b/arch/arm/mach-exynos/mct.c
@@ -29,12 +29,13 @@
#include <mach/regs-mct.h>
#include <asm/mach/time.h>
+#define TICK_BASE_CNT 1
+
enum {
MCT_INT_SPI,
MCT_INT_PPI
};
-static unsigned long clk_cnt_per_tick;
static unsigned long clk_rate;
static unsigned int mct_int_type;
@@ -205,11 +206,14 @@ static int exynos4_comp_set_next_event(unsigned long cycles,
static void exynos4_comp_set_mode(enum clock_event_mode mode,
struct clock_event_device *evt)
{
+ unsigned long cycles_per_jiffy;
exynos4_mct_comp0_stop();
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
- exynos4_mct_comp0_start(mode, clk_cnt_per_tick);
+ cycles_per_jiffy =
+ (((unsigned long long) NSEC_PER_SEC / HZ * evt->mult) >> evt->shift);
+ exynos4_mct_comp0_start(mode, cycles_per_jiffy);
break;
case CLOCK_EVT_MODE_ONESHOT:
@@ -248,9 +252,7 @@ static struct irqaction mct_comp_event_irq = {
static void exynos4_clockevent_init(void)
{
- clk_cnt_per_tick = clk_rate / 2 / HZ;
-
- clockevents_calc_mult_shift(&mct_comp_device, clk_rate / 2, 5);
+ clockevents_calc_mult_shift(&mct_comp_device, clk_rate, 5);
mct_comp_device.max_delta_ns =
clockevent_delta2ns(0xffffffff, &mct_comp_device);
mct_comp_device.min_delta_ns =
@@ -314,12 +316,15 @@ static inline void exynos4_tick_set_mode(enum clock_event_mode mode,
struct clock_event_device *evt)
{
struct mct_clock_event_device *mevt = this_cpu_ptr(&percpu_mct_tick);
+ unsigned long cycles_per_jiffy;
exynos4_mct_tick_stop(mevt);
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
- exynos4_mct_tick_start(clk_cnt_per_tick, mevt);
+ cycles_per_jiffy =
+ (((unsigned long long) NSEC_PER_SEC / HZ * evt->mult) >> evt->shift);
+ exynos4_mct_tick_start(cycles_per_jiffy, mevt);
break;
case CLOCK_EVT_MODE_ONESHOT:
@@ -393,7 +398,7 @@ static void exynos4_mct_tick_init(struct clock_event_device *evt)
evt->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
evt->rating = 450;
- clockevents_calc_mult_shift(evt, clk_rate / 2, 5);
+ clockevents_calc_mult_shift(evt, clk_rate / (TICK_BASE_CNT + 1), 5);
evt->max_delta_ns =
clockevent_delta2ns(0x7fffffff, evt);
evt->min_delta_ns =
@@ -401,7 +406,7 @@ static void exynos4_mct_tick_init(struct clock_event_device *evt)
clockevents_register_device(evt);
- exynos4_mct_write(0x1, mevt->base + MCT_L_TCNTB_OFFSET);
+ exynos4_mct_write(TICK_BASE_CNT, mevt->base + MCT_L_TCNTB_OFFSET);
if (mct_int_type == MCT_INT_SPI) {
if (cpu == 0) {
--
1.7.4.4
--
To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
