Loading arch/arm/Kconfig +2 −2 Original line number Diff line number Diff line Loading @@ -365,8 +365,8 @@ config NO_IDLE_HZ Please note that dynamic tick may affect the accuracy of timekeeping on some platforms depending on the implementation. Currently at least OMAP platform is known to have accurate timekeeping with dynamic tick. Currently at least OMAP and PXA2xx platforms are known to have accurate timekeeping with dynamic tick. config ARCH_DISCONTIGMEM_ENABLE bool Loading arch/arm/mach-pxa/time.c +51 −0 Original line number Diff line number Diff line Loading @@ -70,6 +70,11 @@ static unsigned long pxa_gettimeoffset (void) return usec; } #ifdef CONFIG_NO_IDLE_HZ static unsigned long initial_match; static int match_posponed; #endif static irqreturn_t pxa_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) { Loading @@ -77,6 +82,13 @@ pxa_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) write_seqlock(&xtime_lock); #ifdef CONFIG_NO_IDLE_HZ if (match_posponed) { match_posponed = 0; OSMR0 = initial_match; } #endif /* Loop until we get ahead of the free running timer. * This ensures an exact clock tick count and time accuracy. * IRQs are disabled inside the loop to ensure coherence between Loading Loading @@ -126,6 +138,42 @@ static void __init pxa_timer_init(void) OSCR = 0; /* initialize free-running timer, force first match */ } #ifdef CONFIG_NO_IDLE_HZ static int pxa_dyn_tick_enable_disable(void) { /* nothing to do */ return 0; } static void pxa_dyn_tick_reprogram(unsigned long ticks) { if (ticks > 1) { initial_match = OSMR0; OSMR0 = initial_match + ticks * LATCH; match_posponed = 1; } } static irqreturn_t pxa_dyn_tick_handler(int irq, void *dev_id, struct pt_regs *regs) { if (match_posponed) { match_posponed = 0; OSMR0 = initial_match; if ( (signed long)(initial_match - OSCR) <= 8 ) return pxa_timer_interrupt(irq, dev_id, regs); } return IRQ_NONE; } static struct dyn_tick_timer pxa_dyn_tick = { .enable = pxa_dyn_tick_enable_disable, .disable = pxa_dyn_tick_enable_disable, .reprogram = pxa_dyn_tick_reprogram, .handler = pxa_dyn_tick_handler, }; #endif #ifdef CONFIG_PM static unsigned long osmr[4], oier; Loading Loading @@ -161,4 +209,7 @@ struct sys_timer pxa_timer = { .suspend = pxa_timer_suspend, .resume = pxa_timer_resume, .offset = pxa_gettimeoffset, #ifdef CONFIG_NO_IDLE_HZ .dyn_tick = &pxa_dyn_tick, #endif }; Loading
arch/arm/Kconfig +2 −2 Original line number Diff line number Diff line Loading @@ -365,8 +365,8 @@ config NO_IDLE_HZ Please note that dynamic tick may affect the accuracy of timekeeping on some platforms depending on the implementation. Currently at least OMAP platform is known to have accurate timekeeping with dynamic tick. Currently at least OMAP and PXA2xx platforms are known to have accurate timekeeping with dynamic tick. config ARCH_DISCONTIGMEM_ENABLE bool Loading
arch/arm/mach-pxa/time.c +51 −0 Original line number Diff line number Diff line Loading @@ -70,6 +70,11 @@ static unsigned long pxa_gettimeoffset (void) return usec; } #ifdef CONFIG_NO_IDLE_HZ static unsigned long initial_match; static int match_posponed; #endif static irqreturn_t pxa_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) { Loading @@ -77,6 +82,13 @@ pxa_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) write_seqlock(&xtime_lock); #ifdef CONFIG_NO_IDLE_HZ if (match_posponed) { match_posponed = 0; OSMR0 = initial_match; } #endif /* Loop until we get ahead of the free running timer. * This ensures an exact clock tick count and time accuracy. * IRQs are disabled inside the loop to ensure coherence between Loading Loading @@ -126,6 +138,42 @@ static void __init pxa_timer_init(void) OSCR = 0; /* initialize free-running timer, force first match */ } #ifdef CONFIG_NO_IDLE_HZ static int pxa_dyn_tick_enable_disable(void) { /* nothing to do */ return 0; } static void pxa_dyn_tick_reprogram(unsigned long ticks) { if (ticks > 1) { initial_match = OSMR0; OSMR0 = initial_match + ticks * LATCH; match_posponed = 1; } } static irqreturn_t pxa_dyn_tick_handler(int irq, void *dev_id, struct pt_regs *regs) { if (match_posponed) { match_posponed = 0; OSMR0 = initial_match; if ( (signed long)(initial_match - OSCR) <= 8 ) return pxa_timer_interrupt(irq, dev_id, regs); } return IRQ_NONE; } static struct dyn_tick_timer pxa_dyn_tick = { .enable = pxa_dyn_tick_enable_disable, .disable = pxa_dyn_tick_enable_disable, .reprogram = pxa_dyn_tick_reprogram, .handler = pxa_dyn_tick_handler, }; #endif #ifdef CONFIG_PM static unsigned long osmr[4], oier; Loading Loading @@ -161,4 +209,7 @@ struct sys_timer pxa_timer = { .suspend = pxa_timer_suspend, .resume = pxa_timer_resume, .offset = pxa_gettimeoffset, #ifdef CONFIG_NO_IDLE_HZ .dyn_tick = &pxa_dyn_tick, #endif };