struct sys_timer omap_timer;
-#ifdef CONFIG_OMAP_MPU_TIMER
-
/*
* ---------------------------------------------------------------------------
* MPU timer
return cycles_2_ns(ticks64);
}
-#endif /* CONFIG_OMAP_MPU_TIMER */
-
-#ifdef CONFIG_OMAP_32K_TIMER
-
-#ifdef CONFIG_ARCH_OMAP1510
-#error OMAP 32KHz timer does not currently work on 1510!
-#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 = {
git.samba.org / sfrench / cifs-2.6.git / blobdiff