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-rw-r--r--arch/arm/mach-ns9xxx/time.c172
1 files changed, 134 insertions, 38 deletions
diff --git a/arch/arm/mach-ns9xxx/time.c b/arch/arm/mach-ns9xxx/time.c
index b97d0c5..c3dd1f4 100644
--- a/arch/arm/mach-ns9xxx/time.c
+++ b/arch/arm/mach-ns9xxx/time.c
@@ -11,78 +11,174 @@
#include <linux/jiffies.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
+#include <linux/stringify.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+
#include <asm/arch-ns9xxx/regs-sys.h>
#include <asm/arch-ns9xxx/clock.h>
#include <asm/arch-ns9xxx/irqs.h>
#include <asm/arch/system.h>
#include "generic.h"
-#define TIMERCLOCKSELECT 64
+#define TIMER_CLOCKSOURCE 0
+#define TIMER_CLOCKEVENT 1
+static u32 latch;
+
+static cycle_t ns9xxx_clocksource_read(void)
+{
+ return __raw_readl(SYS_TR(TIMER_CLOCKSOURCE));
+}
-static u32 usecs_per_tick;
+static struct clocksource ns9xxx_clocksource = {
+ .name = "ns9xxx-timer" __stringify(TIMER_CLOCKSOURCE),
+ .rating = 300,
+ .read = ns9xxx_clocksource_read,
+ .mask = CLOCKSOURCE_MASK(32),
+ .shift = 20,
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
-static irqreturn_t
-ns9xxx_timer_interrupt(int irq, void *dev_id)
+static void ns9xxx_clockevent_setmode(enum clock_event_mode mode,
+ struct clock_event_device *clk)
{
- write_seqlock(&xtime_lock);
- timer_tick();
- write_sequnlock(&xtime_lock);
+ u32 tc = __raw_readl(SYS_TC(TIMER_CLOCKEVENT));
+
+ switch(mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ __raw_writel(latch, SYS_TRC(TIMER_CLOCKEVENT));
+ REGSET(tc, SYS_TCx, REN, EN);
+ REGSET(tc, SYS_TCx, INTS, EN);
+ REGSET(tc, SYS_TCx, TEN, EN);
+ break;
+
+ case CLOCK_EVT_MODE_ONESHOT:
+ REGSET(tc, SYS_TCx, REN, DIS);
+ REGSET(tc, SYS_TCx, INTS, EN);
+
+ /* fall through */
+
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ case CLOCK_EVT_MODE_RESUME:
+ default:
+ REGSET(tc, SYS_TCx, TEN, DIS);
+ break;
+ }
+
+ __raw_writel(tc, SYS_TC(TIMER_CLOCKEVENT));
+}
- return IRQ_HANDLED;
+static int ns9xxx_clockevent_setnextevent(unsigned long evt,
+ struct clock_event_device *clk)
+{
+ u32 tc = __raw_readl(SYS_TC(TIMER_CLOCKEVENT));
+
+ if (REGGET(tc, SYS_TCx, TEN)) {
+ REGSET(tc, SYS_TCx, TEN, DIS);
+ __raw_writel(tc, SYS_TC(TIMER_CLOCKEVENT));
+ }
+
+ REGSET(tc, SYS_TCx, TEN, EN);
+
+ __raw_writel(evt, SYS_TRC(TIMER_CLOCKEVENT));
+
+ __raw_writel(tc, SYS_TC(TIMER_CLOCKEVENT));
+
+ return 0;
}
-static unsigned long ns9xxx_timer_gettimeoffset(void)
+static struct clock_event_device ns9xxx_clockevent_device = {
+ .name = "ns9xxx-timer" __stringify(TIMER_CLOCKEVENT),
+ .shift = 20,
+ .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+ .set_mode = ns9xxx_clockevent_setmode,
+ .set_next_event = ns9xxx_clockevent_setnextevent,
+};
+
+static irqreturn_t ns9xxx_clockevent_handler(int irq, void *dev_id)
{
- /* return the microseconds which have passed since the last interrupt
- * was _serviced_. That is, if an interrupt is pending or the counter
- * reloads, return one period more. */
+ int timerno = irq - IRQ_TIMER0;
+ u32 tc;
- u32 counter1 = SYS_TR(0);
- int pending = SYS_ISR & (1 << IRQ_TIMER0);
- u32 counter2 = SYS_TR(0);
- u32 elapsed;
+ struct clock_event_device *evt = &ns9xxx_clockevent_device;
- if (pending || counter2 > counter1)
- elapsed = 2 * SYS_TRC(0) - counter2;
- else
- elapsed = SYS_TRC(0) - counter1;
+ /* clear irq */
+ tc = __raw_readl(SYS_TC(timerno));
+ if (REGGET(tc, SYS_TCx, REN) == SYS_TCx_REN_DIS) {
+ REGSET(tc, SYS_TCx, TEN, DIS);
+ __raw_writel(tc, SYS_TC(timerno));
+ }
+ REGSET(tc, SYS_TCx, INTC, SET);
+ __raw_writel(tc, SYS_TC(timerno));
+ REGSET(tc, SYS_TCx, INTC, UNSET);
+ __raw_writel(tc, SYS_TC(timerno));
- return (elapsed * usecs_per_tick) >> 16;
+ evt->event_handler(evt);
+ return IRQ_HANDLED;
}
-static struct irqaction ns9xxx_timer_irq = {
- .name = "NS9xxx Timer Tick",
- .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
- .handler = ns9xxx_timer_interrupt,
+static struct irqaction ns9xxx_clockevent_action = {
+ .name = "ns9xxx-timer" __stringify(TIMER_CLOCKEVENT),
+ .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
+ .handler = ns9xxx_clockevent_handler,
};
static void __init ns9xxx_timer_init(void)
{
int tc;
- usecs_per_tick =
- SH_DIV(1000000 * TIMERCLOCKSELECT, ns9xxx_cpuclock(), 16);
+ tc = __raw_readl(SYS_TC(TIMER_CLOCKSOURCE));
+ if (REGGET(tc, SYS_TCx, TEN)) {
+ REGSET(tc, SYS_TCx, TEN, DIS);
+ __raw_writel(tc, SYS_TC(TIMER_CLOCKSOURCE));
+ }
- /* disable timer */
- if ((tc = SYS_TC(0)) & SYS_TCx_TEN)
- SYS_TC(0) = tc & ~SYS_TCx_TEN;
-
- SYS_TRC(0) = SH_DIV(ns9xxx_cpuclock(), (TIMERCLOCKSELECT * HZ), 0);
+ __raw_writel(0, SYS_TRC(TIMER_CLOCKSOURCE));
REGSET(tc, SYS_TCx, TEN, EN);
- REGSET(tc, SYS_TCx, TLCS, DIV64); /* This must match TIMERCLOCKSELECT */
- REGSET(tc, SYS_TCx, INTS, EN);
- REGSET(tc, SYS_TCx, UDS, DOWN);
REGSET(tc, SYS_TCx, TDBG, STOP);
+ REGSET(tc, SYS_TCx, TLCS, CPU);
+ REGSET(tc, SYS_TCx, TM, IEE);
+ REGSET(tc, SYS_TCx, INTS, DIS);
+ REGSET(tc, SYS_TCx, UDS, UP);
REGSET(tc, SYS_TCx, TSZ, 32);
REGSET(tc, SYS_TCx, REN, EN);
- SYS_TC(0) = tc;
- setup_irq(IRQ_TIMER0, &ns9xxx_timer_irq);
+ __raw_writel(tc, SYS_TC(TIMER_CLOCKSOURCE));
+
+ ns9xxx_clocksource.mult = clocksource_hz2mult(ns9xxx_cpuclock(),
+ ns9xxx_clocksource.shift);
+
+ clocksource_register(&ns9xxx_clocksource);
+
+ latch = SH_DIV(ns9xxx_cpuclock(), HZ, 0);
+
+ tc = __raw_readl(SYS_TC(TIMER_CLOCKEVENT));
+ REGSET(tc, SYS_TCx, TEN, DIS);
+ REGSET(tc, SYS_TCx, TDBG, STOP);
+ REGSET(tc, SYS_TCx, TLCS, CPU);
+ REGSET(tc, SYS_TCx, TM, IEE);
+ REGSET(tc, SYS_TCx, INTS, DIS);
+ REGSET(tc, SYS_TCx, UDS, DOWN);
+ REGSET(tc, SYS_TCx, TSZ, 32);
+ REGSET(tc, SYS_TCx, REN, EN);
+ __raw_writel(tc, SYS_TC(TIMER_CLOCKEVENT));
+
+ ns9xxx_clockevent_device.mult = div_sc(ns9xxx_cpuclock(),
+ NSEC_PER_SEC, ns9xxx_clockevent_device.shift);
+ ns9xxx_clockevent_device.max_delta_ns =
+ clockevent_delta2ns(-1, &ns9xxx_clockevent_device);
+ ns9xxx_clockevent_device.min_delta_ns =
+ clockevent_delta2ns(1, &ns9xxx_clockevent_device);
+
+ ns9xxx_clockevent_device.cpumask = cpumask_of_cpu(0);
+ clockevents_register_device(&ns9xxx_clockevent_device);
+
+ setup_irq(IRQ_TIMER0 + TIMER_CLOCKEVENT, &ns9xxx_clockevent_action);
}
struct sys_timer ns9xxx_timer = {
.init = ns9xxx_timer_init,
- .offset = ns9xxx_timer_gettimeoffset,
};
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