* 675 Mass Ave, Cambridge, MA 02139, USA.
*/
+#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/delay.h>
struct sys_timer omap_timer;
+#ifdef CONFIG_OMAP_MPU_TIMER
+
/*
* ---------------------------------------------------------------------------
* MPU timer
* will break. On P2, the timer count rate is 6.5 MHz after programming PTV
* with 0. This divides the 13MHz input by 2, and is undocumented.
*/
-#if defined(CONFIG_MACH_OMAP_PERSEUS2) || defined(CONFIG_MACH_OMAP_FSAMPLE)
+#ifdef CONFIG_MACH_OMAP_PERSEUS2
/* REVISIT: This ifdef construct should be replaced by a query to clock
* framework to see if timer base frequency is 12.0, 13.0 or 19.2 MHz.
*/
static struct irqaction omap_mpu_timer_irq = {
.name = "mpu timer",
- .flags = IRQF_DISABLED | IRQF_TIMER,
+ .flags = SA_INTERRUPT | SA_TIMER,
.handler = omap_mpu_timer_interrupt,
};
static struct irqaction omap_mpu_timer1_irq = {
.name = "mpu timer1 overflow",
- .flags = IRQF_DISABLED,
+ .flags = SA_INTERRUPT,
.handler = omap_mpu_timer1_interrupt,
};
return cycles_2_ns(ticks64);
}
+#endif /* CONFIG_OMAP_MPU_TIMER */
+
+#ifdef CONFIG_OMAP_32K_TIMER
+
+#ifdef CONFIG_ARCH_OMAP15XX
+#error OMAP 32KHz timer does not currently work on 15XX!
+#endif
+
+/*
+ * ---------------------------------------------------------------------------
+ * 32KHz OS timer
+ *
+ * This currently works only on 16xx, as 1510 does not have the continuous
+ * 32KHz synchronous timer. The 32KHz synchronous timer is used to keep track
+ * of time in addition to the 32KHz OS timer. Using only the 32KHz OS timer
+ * on 1510 would be possible, but the timer would not be as accurate as
+ * with the 32KHz synchronized timer.
+ * ---------------------------------------------------------------------------
+ */
+#define OMAP_32K_TIMER_BASE 0xfffb9000
+#define OMAP_32K_TIMER_CR 0x08
+#define OMAP_32K_TIMER_TVR 0x00
+#define OMAP_32K_TIMER_TCR 0x04
+
+#define OMAP_32K_TICKS_PER_HZ (32768 / HZ)
+
+/*
+ * TRM says 1 / HZ = ( TVR + 1) / 32768, so TRV = (32768 / HZ) - 1
+ * so with HZ = 100, TVR = 327.68.
+ */
+#define OMAP_32K_TIMER_TICK_PERIOD ((32768 / HZ) - 1)
+#define TIMER_32K_SYNCHRONIZED 0xfffbc410
+
+#define JIFFIES_TO_HW_TICKS(nr_jiffies, clock_rate) \
+ (((nr_jiffies) * (clock_rate)) / HZ)
+
+static inline void omap_32k_timer_write(int val, int reg)
+{
+ omap_writew(val, reg + OMAP_32K_TIMER_BASE);
+}
+
+static inline unsigned long omap_32k_timer_read(int reg)
+{
+ return omap_readl(reg + OMAP_32K_TIMER_BASE) & 0xffffff;
+}
+
+/*
+ * The 32KHz synchronized timer is an additional timer on 16xx.
+ * It is always running.
+ */
+static inline unsigned long omap_32k_sync_timer_read(void)
+{
+ return omap_readl(TIMER_32K_SYNCHRONIZED);
+}
+
+static inline void omap_32k_timer_start(unsigned long load_val)
+{
+ omap_32k_timer_write(load_val, OMAP_32K_TIMER_TVR);
+ omap_32k_timer_write(0x0f, OMAP_32K_TIMER_CR);
+}
+
+static inline void omap_32k_timer_stop(void)
+{
+ omap_32k_timer_write(0x0, OMAP_32K_TIMER_CR);
+}
+
+/*
+ * Rounds down to nearest usec. Note that this will overflow for larger values.
+ */
+static inline unsigned long omap_32k_ticks_to_usecs(unsigned long ticks_32k)
+{
+ return (ticks_32k * 5*5*5*5*5*5) >> 9;
+}
+
+/*
+ * Rounds down to nearest nsec.
+ */
+static inline unsigned long long
+omap_32k_ticks_to_nsecs(unsigned long ticks_32k)
+{
+ return (unsigned long long) ticks_32k * 1000 * 5*5*5*5*5*5 >> 9;
+}
+
+static unsigned long omap_32k_last_tick = 0;
+
+/*
+ * Returns elapsed usecs since last 32k timer interrupt
+ */
+static unsigned long omap_32k_timer_gettimeoffset(void)
+{
+ unsigned long now = omap_32k_sync_timer_read();
+ return omap_32k_ticks_to_usecs(now - omap_32k_last_tick);
+}
+
+/*
+ * Returns current time from boot in nsecs. It's OK for this to wrap
+ * around for now, as it's just a relative time stamp.
+ */
+unsigned long long sched_clock(void)
+{
+ return omap_32k_ticks_to_nsecs(omap_32k_sync_timer_read());
+}
+
+/*
+ * Timer interrupt for 32KHz timer. When dynamic tick is enabled, this
+ * function is also called from other interrupts to remove latency
+ * issues with dynamic tick. In the dynamic tick case, we need to lock
+ * with irqsave.
+ */
+static irqreturn_t omap_32k_timer_interrupt(int irq, void *dev_id,
+ struct pt_regs *regs)
+{
+ unsigned long flags;
+ unsigned long now;
+
+ write_seqlock_irqsave(&xtime_lock, flags);
+ now = omap_32k_sync_timer_read();
+
+ while (now - omap_32k_last_tick >= OMAP_32K_TICKS_PER_HZ) {
+ omap_32k_last_tick += OMAP_32K_TICKS_PER_HZ;
+ timer_tick(regs);
+ }
+
+ /* Restart timer so we don't drift off due to modulo or dynamic tick.
+ * By default we program the next timer to be continuous to avoid
+ * latencies during high system load. During dynamic tick operation the
+ * continuous timer can be overridden from pm_idle to be longer.
+ */
+ omap_32k_timer_start(omap_32k_last_tick + OMAP_32K_TICKS_PER_HZ - now);
+ write_sequnlock_irqrestore(&xtime_lock, flags);
+
+ 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 | 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();
+ omap_32k_timer_start(OMAP_32K_TIMER_TICK_PERIOD);
+}
+#endif /* CONFIG_OMAP_32K_TIMER */
/*
* ---------------------------------------------------------------------------
*/
static void __init omap_timer_init(void)
{
+#if defined(CONFIG_OMAP_MPU_TIMER)
omap_init_mpu_timer();
+#elif defined(CONFIG_OMAP_32K_TIMER)
+ omap_init_32k_timer();
+#else
+#error No system timer selected in Kconfig!
+#endif
}
struct sys_timer omap_timer = {
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