netx: add support for clockevents
This is based on a patch by Luotao Fu <lfu@pengutronix.de>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Luotao Fu <lfu@pengutronix.de>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
diff --git a/arch/arm/mach-netx/time.c b/arch/arm/mach-netx/time.c
index 34a6a15..d51d627 100644
--- a/arch/arm/mach-netx/time.c
+++ b/arch/arm/mach-netx/time.c
@@ -21,25 +21,80 @@
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/clocksource.h>
+#include <linux/clockchips.h>
#include <linux/io.h>
#include <mach/hardware.h>
#include <asm/mach/time.h>
#include <mach/netx-regs.h>
+#define TIMER_CLOCKEVENT 0
#define TIMER_CLOCKSOURCE 1
+static void netx_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *clk)
+{
+ u32 tmode;
+
+ /* disable timer */
+ writel(0, NETX_GPIO_COUNTER_CTRL(TIMER_CLOCKEVENT));
+
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ writel(LATCH, NETX_GPIO_COUNTER_MAX(TIMER_CLOCKEVENT));
+ tmode = NETX_GPIO_COUNTER_CTRL_RST_EN |
+ NETX_GPIO_COUNTER_CTRL_IRQ_EN |
+ NETX_GPIO_COUNTER_CTRL_RUN;
+ break;
+
+ case CLOCK_EVT_MODE_ONESHOT:
+ writel(0, NETX_GPIO_COUNTER_MAX(TIMER_CLOCKEVENT));
+ tmode = NETX_GPIO_COUNTER_CTRL_IRQ_EN |
+ NETX_GPIO_COUNTER_CTRL_RUN;
+ break;
+
+ default:
+ WARN(1, "%s: unhandled mode %d\n", __func__, mode);
+ /* fall through */
+
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_RESUME:
+ tmode = 0;
+ break;
+ }
+
+ writel(tmode, NETX_GPIO_COUNTER_CTRL(TIMER_CLOCKEVENT));
+}
+
+static int netx_set_next_event(unsigned long evt,
+ struct clock_event_device *clk)
+{
+ writel(0 - evt, NETX_GPIO_COUNTER_CURRENT(TIMER_CLOCKEVENT));
+ return 0;
+}
+
+static struct clock_event_device netx_clockevent = {
+ .name = "netx-timer" __stringify(TIMER_CLOCKEVENT),
+ .shift = 32,
+ .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+ .set_next_event = netx_set_next_event,
+ .set_mode = netx_set_mode,
+};
+
/*
* IRQ handler for the timer
*/
static irqreturn_t
netx_timer_interrupt(int irq, void *dev_id)
{
- timer_tick();
+ struct clock_event_device *evt = &netx_clockevent;
/* acknowledge interrupt */
writel(COUNTER_BIT(0), NETX_GPIO_IRQ);
+ evt->event_handler(evt);
+
return IRQ_HANDLED;
}
@@ -99,6 +154,17 @@
clocksource_netx.mult =
clocksource_hz2mult(CLOCK_TICK_RATE, clocksource_netx.shift);
clocksource_register(&clocksource_netx);
+
+ netx_clockevent.mult = div_sc(CLOCK_TICK_RATE, NSEC_PER_SEC,
+ netx_clockevent.shift);
+ netx_clockevent.max_delta_ns =
+ clockevent_delta2ns(0xfffffffe, &netx_clockevent);
+ /* with max_delta_ns >= delta2ns(0x800) the system currently runs fine.
+ * Adding some safety ... */
+ netx_clockevent.min_delta_ns =
+ clockevent_delta2ns(0xa00, &netx_clockevent);
+ netx_clockevent.cpumask = cpumask_of_cpu(0);
+ clockevents_register_device(&netx_clockevent);
}
struct sys_timer netx_timer = {