X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=arch%2Farm%2Fmach-omap1%2Ftime.c;h=a85fe6066bc47d9a3e6168ff1686b6356dcec200;hb=2514395ef88b46e895726a8d40966cb83de7940c;hp=191a9b1ee9b7168f1ef3b561b08f732e55b4c2bf;hpb=2fc2991175bf77395e6b15fe6b2304d3bf72da40;p=powerpc.git diff --git a/arch/arm/mach-omap1/time.c b/arch/arm/mach-omap1/time.c index 191a9b1ee9..a85fe6066b 100644 --- a/arch/arm/mach-omap1/time.c +++ b/arch/arm/mach-omap1/time.c @@ -51,8 +51,6 @@ struct sys_timer omap_timer; -#ifdef CONFIG_OMAP_MPU_TIMER - /* * --------------------------------------------------------------------------- * MPU timer @@ -222,195 +220,6 @@ unsigned long long sched_clock(void) 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 */ /* * --------------------------------------------------------------------------- @@ -419,13 +228,7 @@ static __init void omap_init_32k_timer(void) */ 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 = {