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Diffstat (limited to 'arch/arm/plat-iop/time.c')
-rw-r--r--arch/arm/plat-iop/time.c168
1 files changed, 120 insertions, 48 deletions
diff --git a/arch/arm/plat-iop/time.c b/arch/arm/plat-iop/time.c
index 06282dffbdc..6ad65d8ae23 100644
--- a/arch/arm/plat-iop/time.c
+++ b/arch/arm/plat-iop/time.c
@@ -18,81 +18,153 @@
#include <linux/time.h>
#include <linux/init.h>
#include <linux/timex.h>
-#include <asm/hardware.h>
-#include <asm/io.h>
+#include <linux/io.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/export.h>
+#include <linux/sched_clock.h>
+#include <mach/hardware.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
#include <asm/mach/irq.h>
#include <asm/mach/time.h>
+#include <mach/time.h>
-#ifdef CONFIG_ARCH_IOP32X
-#define IRQ_IOP3XX_TIMER0 IRQ_IOP32X_TIMER0
-#else
-#ifdef CONFIG_ARCH_IOP33X
-#define IRQ_IOP3XX_TIMER0 IRQ_IOP33X_TIMER0
-#endif
-#endif
-
-static unsigned long ticks_per_jiffy;
-static unsigned long ticks_per_usec;
-static unsigned long next_jiffy_time;
+/*
+ * Minimum clocksource/clockevent timer range in seconds
+ */
+#define IOP_MIN_RANGE 4
-unsigned long iop3xx_gettimeoffset(void)
+/*
+ * IOP clocksource (free-running timer 1).
+ */
+static cycle_t notrace iop_clocksource_read(struct clocksource *unused)
{
- unsigned long offset;
+ return 0xffffffffu - read_tcr1();
+}
- offset = next_jiffy_time - *IOP3XX_TU_TCR1;
+static struct clocksource iop_clocksource = {
+ .name = "iop_timer1",
+ .rating = 300,
+ .read = iop_clocksource_read,
+ .mask = CLOCKSOURCE_MASK(32),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
- return offset / ticks_per_usec;
+/*
+ * IOP sched_clock() implementation via its clocksource.
+ */
+static u64 notrace iop_read_sched_clock(void)
+{
+ return 0xffffffffu - read_tcr1();
}
-static irqreturn_t
-iop3xx_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+/*
+ * IOP clockevents (interrupting timer 0).
+ */
+static int iop_set_next_event(unsigned long delta,
+ struct clock_event_device *unused)
{
- write_seqlock(&xtime_lock);
+ u32 tmr = IOP_TMR_PRIVILEGED | IOP_TMR_RATIO_1_1;
+
+ BUG_ON(delta == 0);
+ write_tmr0(tmr & ~(IOP_TMR_EN | IOP_TMR_RELOAD));
+ write_tcr0(delta);
+ write_tmr0((tmr & ~IOP_TMR_RELOAD) | IOP_TMR_EN);
+
+ return 0;
+}
- iop3xx_cp6_enable();
- asm volatile("mcr p6, 0, %0, c6, c1, 0" : : "r" (1));
- iop3xx_cp6_disable();
+static unsigned long ticks_per_jiffy;
- while ((signed long)(next_jiffy_time - *IOP3XX_TU_TCR1)
- >= ticks_per_jiffy) {
- timer_tick(regs);
- next_jiffy_time -= ticks_per_jiffy;
+static void iop_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *unused)
+{
+ u32 tmr = read_tmr0();
+
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ write_tmr0(tmr & ~IOP_TMR_EN);
+ write_tcr0(ticks_per_jiffy - 1);
+ write_trr0(ticks_per_jiffy - 1);
+ tmr |= (IOP_TMR_RELOAD | IOP_TMR_EN);
+ break;
+ case CLOCK_EVT_MODE_ONESHOT:
+ /* ->set_next_event sets period and enables timer */
+ tmr &= ~(IOP_TMR_RELOAD | IOP_TMR_EN);
+ break;
+ case CLOCK_EVT_MODE_RESUME:
+ tmr |= IOP_TMR_EN;
+ break;
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ case CLOCK_EVT_MODE_UNUSED:
+ default:
+ tmr &= ~IOP_TMR_EN;
+ break;
}
- write_sequnlock(&xtime_lock);
+ write_tmr0(tmr);
+}
+
+static struct clock_event_device iop_clockevent = {
+ .name = "iop_timer0",
+ .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+ .rating = 300,
+ .set_next_event = iop_set_next_event,
+ .set_mode = iop_set_mode,
+};
+
+static irqreturn_t
+iop_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = dev_id;
+ write_tisr(1);
+ evt->event_handler(evt);
return IRQ_HANDLED;
}
-static struct irqaction iop3xx_timer_irq = {
- .name = "IOP3XX Timer Tick",
- .handler = iop3xx_timer_interrupt,
- .flags = IRQF_DISABLED | IRQF_TIMER,
+static struct irqaction iop_timer_irq = {
+ .name = "IOP Timer Tick",
+ .handler = iop_timer_interrupt,
+ .flags = IRQF_TIMER | IRQF_IRQPOLL,
+ .dev_id = &iop_clockevent,
};
-void __init iop3xx_init_time(unsigned long tick_rate)
+static unsigned long iop_tick_rate;
+unsigned long get_iop_tick_rate(void)
+{
+ return iop_tick_rate;
+}
+EXPORT_SYMBOL(get_iop_tick_rate);
+
+void __init iop_init_time(unsigned long tick_rate)
{
u32 timer_ctl;
- ticks_per_jiffy = (tick_rate + HZ/2) / HZ;
- ticks_per_usec = tick_rate / 1000000;
- next_jiffy_time = 0xffffffff;
+ sched_clock_register(iop_read_sched_clock, 32, tick_rate);
- timer_ctl = IOP3XX_TMR_EN | IOP3XX_TMR_PRIVILEGED |
- IOP3XX_TMR_RELOAD | IOP3XX_TMR_RATIO_1_1;
+ ticks_per_jiffy = DIV_ROUND_CLOSEST(tick_rate, HZ);
+ iop_tick_rate = tick_rate;
+
+ timer_ctl = IOP_TMR_EN | IOP_TMR_PRIVILEGED |
+ IOP_TMR_RELOAD | IOP_TMR_RATIO_1_1;
+
+ /*
+ * Set up interrupting clockevent timer 0.
+ */
+ write_tmr0(timer_ctl & ~IOP_TMR_EN);
+ write_tisr(1);
+ setup_irq(IRQ_IOP_TIMER0, &iop_timer_irq);
+ iop_clockevent.cpumask = cpumask_of(0);
+ clockevents_config_and_register(&iop_clockevent, tick_rate,
+ 0xf, 0xfffffffe);
/*
- * We use timer 0 for our timer interrupt, and timer 1 as
- * monotonic counter for tracking missed jiffies.
+ * Set up free-running clocksource timer 1.
*/
- iop3xx_cp6_enable();
- asm volatile("mcr p6, 0, %0, c4, c1, 0" : : "r" (ticks_per_jiffy - 1));
- asm volatile("mcr p6, 0, %0, c0, c1, 0" : : "r" (timer_ctl));
- asm volatile("mcr p6, 0, %0, c5, c1, 0" : : "r" (0xffffffff));
- asm volatile("mcr p6, 0, %0, c1, c1, 0" : : "r" (timer_ctl));
- iop3xx_cp6_disable();
-
- setup_irq(IRQ_IOP3XX_TIMER0, &iop3xx_timer_irq);
+ write_trr1(0xffffffff);
+ write_tcr1(0xffffffff);
+ write_tmr1(timer_ctl);
+ clocksource_register_hz(&iop_clocksource, tick_rate);
}