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authorUwe Kleine-König <u.kleine-koenig@pengutronix.de>2013-11-05 10:03:19 +0100
committerLinus Walleij <linus.walleij@linaro.org>2013-11-26 21:00:21 +0100
commit6a79799d5654bb7800614e8b7a009252be7ff90e (patch)
treedf74f5979cc6de74c6bf2d441505a7e6a23845e7 /arch/arm
parent8ddd0f6fa6b542270517affb7d6657061c615ba9 (diff)
downloadlinux-linaro-stable-6a79799d5654bb7800614e8b7a009252be7ff90e.tar.gz
ARM: u300: fix timekeeping when periodic mode is used
To determine the value to write to the hardware's timer counter register the symbol CLOCK_TICK_RATE is used. This value is a dummy value on u300 though. So instead use the clock rate that is used for oneshot mode. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'arch/arm')
-rw-r--r--arch/arm/mach-u300/timer.c38
1 files changed, 24 insertions, 14 deletions
diff --git a/arch/arm/mach-u300/timer.c b/arch/arm/mach-u300/timer.c
index 9a5f9fb352ce..5226162fac69 100644
--- a/arch/arm/mach-u300/timer.c
+++ b/arch/arm/mach-u300/timer.c
@@ -184,11 +184,13 @@
#define U300_TIMER_APP_CRC (0x100)
#define U300_TIMER_APP_CRC_CLOCK_REQUEST_ENABLE (0x00000001)
-#define TICKS_PER_JIFFY ((CLOCK_TICK_RATE + (HZ/2)) / HZ)
-#define US_PER_TICK ((1000000 + (HZ/2)) / HZ)
-
static void __iomem *u300_timer_base;
+struct u300_clockevent_data {
+ struct clock_event_device cevd;
+ unsigned ticks_per_jiffy;
+};
+
/*
* The u300_set_mode() function is always called first, if we
* have oneshot timer active, the oneshot scheduling function
@@ -197,6 +199,9 @@ static void __iomem *u300_timer_base;
static void u300_set_mode(enum clock_event_mode mode,
struct clock_event_device *evt)
{
+ struct u300_clockevent_data *cevdata =
+ container_of(evt, struct u300_clockevent_data, cevd);
+
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
/* Disable interrupts on GPT1 */
@@ -209,7 +214,7 @@ static void u300_set_mode(enum clock_event_mode mode,
* Set the periodic mode to a certain number of ticks per
* jiffy.
*/
- writel(TICKS_PER_JIFFY,
+ writel(cevdata->ticks_per_jiffy,
u300_timer_base + U300_TIMER_APP_GPT1TC);
/*
* Set continuous mode, so the timer keeps triggering
@@ -305,20 +310,23 @@ static int u300_set_next_event(unsigned long cycles,
return 0;
}
-
-/* Use general purpose timer 1 as clock event */
-static struct clock_event_device clockevent_u300_1mhz = {
- .name = "GPT1",
- .rating = 300, /* Reasonably fast and accurate clock event */
- .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
- .set_next_event = u300_set_next_event,
- .set_mode = u300_set_mode,
+static struct u300_clockevent_data u300_clockevent_data = {
+ /* Use general purpose timer 1 as clock event */
+ .cevd = {
+ .name = "GPT1",
+ /* Reasonably fast and accurate clock event */
+ .rating = 300,
+ .features = CLOCK_EVT_FEAT_PERIODIC |
+ CLOCK_EVT_FEAT_ONESHOT,
+ .set_next_event = u300_set_next_event,
+ .set_mode = u300_set_mode,
+ },
};
/* Clock event timer interrupt handler */
static irqreturn_t u300_timer_interrupt(int irq, void *dev_id)
{
- struct clock_event_device *evt = &clockevent_u300_1mhz;
+ struct clock_event_device *evt = &u300_clockevent_data.cevd;
/* ACK/Clear timer IRQ for the APP GPT1 Timer */
writel(U300_TIMER_APP_GPT1IA_IRQ_ACK,
@@ -379,6 +387,8 @@ static void __init u300_timer_init_of(struct device_node *np)
clk_prepare_enable(clk);
rate = clk_get_rate(clk);
+ u300_clockevent_data.ticks_per_jiffy = DIV_ROUND_CLOSEST(rate, HZ);
+
setup_sched_clock(u300_read_sched_clock, 32, rate);
u300_delay_timer.read_current_timer = &u300_read_current_timer;
@@ -428,7 +438,7 @@ static void __init u300_timer_init_of(struct device_node *np)
pr_err("timer: failed to initialize U300 clock source\n");
/* Configure and register the clockevent */
- clockevents_config_and_register(&clockevent_u300_1mhz, rate,
+ clockevents_config_and_register(&u300_clockevent_data.cevd, rate,
1, 0xffffffff);
/*