[PATCH] ARM: 2771/1: Dynamic Tick support for OMAP, take 4

[linux-2.6] / arch / arm / mach-omap / time.c

diff --git a/arch/arm/mach-omap/time.c b/arch/arm/mach-omap/time.c
index 4205fdcb632c238fd173df7ffc51b0bedfeed45b..dd34e9f4c4139cebd68da923e1b839e8164c762a 100644 (file)
--- a/arch/arm/mach-omap/time.c
+++ b/arch/arm/mach-omap/time.c
@@ -4,7 +4,7 @@
  * OMAP Timers
  *
  * Copyright (C) 2004 Nokia Corporation
- * Partial timer rewrite and additional VST timer support by
+ * Partial timer rewrite and additional dynamic tick timer support by
  * Tony Lindgen <tony@atomide.com> and
  * Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>
  *
@@ -188,8 +188,8 @@ static irqreturn_t omap_mpu_timer_interrupt(int irq, void *dev_id,
 
 static struct irqaction omap_mpu_timer_irq = {
        .name           = "mpu timer",
-       .flags          = SA_INTERRUPT,
-       .handler        = omap_mpu_timer_interrupt
+       .flags          = SA_INTERRUPT | SA_TIMER,
+       .handler        = omap_mpu_timer_interrupt,
 };
 
 static unsigned long omap_mpu_timer1_overflows;
@@ -203,7 +203,7 @@ static irqreturn_t omap_mpu_timer1_interrupt(int irq, void *dev_id,
 static struct irqaction omap_mpu_timer1_irq = {
        .name           = "mpu timer1 overflow",
        .flags          = SA_INTERRUPT,
-       .handler        = omap_mpu_timer1_interrupt
+       .handler        = omap_mpu_timer1_interrupt,
 };
 
 static __init void omap_init_mpu_timer(void)
@@ -261,7 +261,6 @@ unsigned long long sched_clock(void)
  * so with HZ = 100, TVR = 327.68.
  */
 #define OMAP_32K_TIMER_TICK_PERIOD     ((32768 / HZ) - 1)
-#define MAX_SKIP_JIFFIES               25
 #define TIMER_32K_SYNCHRONIZED         0xfffbc410
 
 #define JIFFIES_TO_HW_TICKS(nr_jiffies, clock_rate)                    \
@@ -347,14 +346,55 @@ static irqreturn_t omap_32k_timer_interrupt(int irq, void *dev_id,
        return IRQ_HANDLED;
 }
 
+#ifdef CONFIG_NO_IDLE_HZ
+/*
+ * Programs the next timer interrupt needed. Called when dynamic tick is
+ * enabled, and to reprogram the ticks to skip from pm_idle. Note that
+ * we can keep the timer continuous, and don't need to set it to run in
+ * one-shot mode. This is because the timer will get reprogrammed again
+ * after next interrupt.
+ */
+void omap_32k_timer_reprogram(unsigned long next_tick)
+{
+       omap_32k_timer_start(JIFFIES_TO_HW_TICKS(next_tick, 32768) + 1);
+}
+
+static struct irqaction omap_32k_timer_irq;
+extern struct timer_update_handler timer_update;
+
+static int omap_32k_timer_enable_dyn_tick(void)
+{
+       /* No need to reprogram timer, just use the next interrupt */
+       return 0;
+}
+
+static int omap_32k_timer_disable_dyn_tick(void)
+{
+       omap_32k_timer_start(OMAP_32K_TIMER_TICK_PERIOD);
+       return 0;
+}
+
+static struct dyn_tick_timer omap_dyn_tick_timer = {
+       .enable         = omap_32k_timer_enable_dyn_tick,
+       .disable        = omap_32k_timer_disable_dyn_tick,
+       .reprogram      = omap_32k_timer_reprogram,
+       .handler        = omap_32k_timer_interrupt,
+};
+#endif /* CONFIG_NO_IDLE_HZ */
+
 static struct irqaction omap_32k_timer_irq = {
        .name           = "32KHz timer",
-       .flags          = SA_INTERRUPT,
-       .handler        = omap_32k_timer_interrupt
+       .flags          = SA_INTERRUPT | SA_TIMER,
+       .handler        = omap_32k_timer_interrupt,
 };
 
 static __init void omap_init_32k_timer(void)
 {
+
+#ifdef CONFIG_NO_IDLE_HZ
+       omap_timer.dyn_tick = &omap_dyn_tick_timer;
+#endif
+
        setup_irq(INT_OS_TIMER, &omap_32k_timer_irq);
        omap_timer.offset  = omap_32k_timer_gettimeoffset;
        omap_32k_last_tick = omap_32k_sync_timer_read();