From: Sascha Hauer <[EMAIL PROTECTED]>
Add a clockevent driver for i.MX systems.
Signed-off-by: Luotao Fu <[EMAIL PROTECTED]>
Signed-off-by: Sascha Hauer <[EMAIL PROTECTED]>
Index: arch/arm/mach-imx/time.c
===================================================================
--- arch/arm/mach-imx/time.c.orig
+++ arch/arm/mach-imx/time.c
@@ -15,6 +15,7 @@
#include <linux/irq.h>
#include <linux/time.h>
#include <linux/clocksource.h>
+#include <linux/clockchips.h>
#include <asm/hardware.h>
#include <asm/io.h>
@@ -25,6 +26,9 @@
/* Use timer 1 as system timer */
#define TIMER_BASE IMX_TIM1_BASE
+static int __init imx_clockevent_init(void);
+static struct clock_event_device clockevent_imx;
+enum clock_event_mode clockevent_mode = 0;
static unsigned long evt_diff;
/*
@@ -42,9 +46,12 @@ imx_timer_interrupt(int irq, void *dev_i
if (tstat & TSTAT_COMP) {
do {
- write_seqlock(&xtime_lock);
- timer_tick();
- write_sequnlock(&xtime_lock);
+ if (clockevent_imx.event_handler)
+ clockevent_imx.event_handler();
+
+ if (clockevent_mode != CLOCK_EVT_PERIODIC)
+ break;
+
IMX_TCMP(TIMER_BASE) += evt_diff;
} while (unlikely((int32_t)(IMX_TCMP(TIMER_BASE)
@@ -104,6 +111,9 @@ static void __init imx_timer_init(void)
imx_timer_hardware_init();
imx_clocksource_init();
+ evt_diff = LATCH;
+ imx_clockevent_init();
+
/*
* Make irqs happen for the system timer
*/
@@ -113,3 +123,37 @@ static void __init imx_timer_init(void)
struct sys_timer imx_timer = {
.init = imx_timer_init,
};
+
+static void imx_set_next_event(unsigned long evt,
+ struct clock_event_device *unused)
+{
+ evt_diff = evt;
+ IMX_TCMP(IMX_TIM1_BASE) = IMX_TCN(IMX_TIM1_BASE) + evt;
+}
+
+static void imx_set_mode(enum clock_event_mode mode, struct clock_event_device
*evt)
+{
+ clockevent_mode = mode;
+}
+
+static struct clock_event_device clockevent_imx = {
+ .name = "imx_timer1",
+ .capabilities = CLOCK_CAP_NEXTEVT | CLOCK_CAP_TICK |
+ CLOCK_CAP_UPDATE | CLOCK_CAP_PROFILE,
+ .shift = 32,
+ .set_mode = imx_set_mode,
+ .set_next_event = imx_set_next_event,
+};
+
+static int __init imx_clockevent_init(void)
+{
+ clockevent_imx.mult = div_sc(imx_get_perclk1(), NSEC_PER_SEC,
+ clockevent_imx.shift);
+ clockevent_imx.max_delta_ns =
+ clockevent_delta2ns(0xfffffffe, &clockevent_imx);
+ clockevent_imx.min_delta_ns =
+ clockevent_delta2ns(0xf, &clockevent_imx);
+ register_local_clockevent(&clockevent_imx);
+
+ return 0;
+}
--
Dipl.-Ing. Robert Schwebel | http://www.pengutronix.de
Pengutronix - Linux Solutions for Science and Industry
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