From 13edd86d7a8b64735c60c308faac785a6f2257b2 Mon Sep 17 00:00:00 2001 From: Russell King Date: Fri, 15 Jan 2010 21:49:23 +0000 Subject: [PATCH] ARM: Integrator: convert to generic clockevent support Signed-off-by: Russell King --- arch/arm/Kconfig | 1 + arch/arm/mach-integrator/core.c | 115 +++++++++++++++++++++----------- 2 files changed, 78 insertions(+), 38 deletions(-) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 7698d8705a8..86fecec1600 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -242,6 +242,7 @@ config ARCH_INTEGRATOR select COMMON_CLKDEV select ICST525 select GENERIC_TIME + select GENERIC_CLOCKEVENTS help Support for ARM's Integrator platform. diff --git a/arch/arm/mach-integrator/core.c b/arch/arm/mach-integrator/core.c index 87c6f980944..b1ccbe3f233 100644 --- a/arch/arm/mach-integrator/core.c +++ b/arch/arm/mach-integrator/core.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include @@ -275,61 +276,99 @@ static void integrator_clocksource_init(u32 khz) clocksource_register(cs); } +static void __iomem * const clkevt_base = (void __iomem *)TIMER1_VA_BASE; + /* * IRQ handler for the timer */ -static irqreturn_t -integrator_timer_interrupt(int irq, void *dev_id) +static irqreturn_t integrator_timer_interrupt(int irq, void *dev_id) { - /* - * clear the interrupt - */ - writel(1, TIMER1_VA_BASE + TIMER_INTCLR); + struct clock_event_device *evt = dev_id; - timer_tick(); + /* clear the interrupt */ + writel(1, clkevt_base + TIMER_INTCLR); + + evt->event_handler(evt); return IRQ_HANDLED; } -static struct irqaction integrator_timer_irq = { - .name = "Integrator Timer Tick", - .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, - .handler = integrator_timer_interrupt, +static void clkevt_set_mode(enum clock_event_mode mode, struct clock_event_device *evt) +{ + u32 ctrl = readl(clkevt_base + TIMER_CTRL) & ~TIMER_CTRL_ENABLE; + + BUG_ON(mode == CLOCK_EVT_MODE_ONESHOT); + + if (mode == CLOCK_EVT_MODE_PERIODIC) { + writel(ctrl, clkevt_base + TIMER_CTRL); + writel(timer_reload, clkevt_base + TIMER_LOAD); + ctrl |= TIMER_CTRL_PERIODIC | TIMER_CTRL_ENABLE; + } + + writel(ctrl, clkevt_base + TIMER_CTRL); +} + +static int clkevt_set_next_event(unsigned long next, struct clock_event_device *evt) +{ + unsigned long ctrl = readl(clkevt_base + TIMER_CTRL); + + writel(ctrl & ~TIMER_CTRL_ENABLE, clkevt_base + TIMER_CTRL); + writel(next, clkevt_base + TIMER_LOAD); + writel(ctrl | TIMER_CTRL_ENABLE, clkevt_base + TIMER_CTRL); + + return 0; +} + +static struct clock_event_device integrator_clockevent = { + .name = "timer1", + .shift = 34, + .features = CLOCK_EVT_FEAT_PERIODIC, + .set_mode = clkevt_set_mode, + .set_next_event = clkevt_set_next_event, + .rating = 300, + .cpumask = cpu_all_mask, }; +static struct irqaction integrator_timer_irq = { + .name = "timer", + .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, + .handler = integrator_timer_interrupt, + .dev_id = &integrator_clockevent, +}; + +static void integrator_clockevent_init(u32 khz, unsigned int ctrl) +{ + struct clock_event_device *evt = &integrator_clockevent; + + if (khz * 1000 > 0x100000 * HZ) { + khz /= 256; + ctrl |= TIMER_CTRL_DIV256; + } else if (khz * 1000 > 0x10000 * HZ) { + khz /= 16; + ctrl |= TIMER_CTRL_DIV16; + } + + timer_reload = khz * 1000 / HZ; + writel(ctrl, clkevt_base + TIMER_CTRL); + + evt->irq = IRQ_TIMERINT1; + evt->mult = div_sc(khz, NSEC_PER_MSEC, evt->shift); + evt->max_delta_ns = clockevent_delta2ns(0xffff, evt); + evt->min_delta_ns = clockevent_delta2ns(0xf, evt); + + setup_irq(IRQ_TIMERINT1, &integrator_timer_irq); + clockevents_register_device(evt); +} + /* - * Set up timer interrupt, and return the current time in seconds. + * Set up timer(s). */ void __init integrator_time_init(unsigned long reload, unsigned int ctrl) { - unsigned int timer_ctrl = TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC; - - integrator_clocksource_init(reload * HZ / 1000); - - timer_reload = reload; - timer_ctrl |= ctrl; - - if (timer_reload > 0x100000) { - timer_reload >>= 8; - timer_ctrl |= TIMER_CTRL_DIV256; - } else if (timer_reload > 0x010000) { - timer_reload >>= 4; - timer_ctrl |= TIMER_CTRL_DIV16; - } - - /* - * Initialise to a known state (all timers off) - */ writel(0, TIMER0_VA_BASE + TIMER_CTRL); writel(0, TIMER1_VA_BASE + TIMER_CTRL); writel(0, TIMER2_VA_BASE + TIMER_CTRL); - writel(timer_reload, TIMER1_VA_BASE + TIMER_LOAD); - writel(timer_reload, TIMER1_VA_BASE + TIMER_VALUE); - writel(timer_ctrl, TIMER1_VA_BASE + TIMER_CTRL); - - /* - * Make irqs happen for the system timer - */ - setup_irq(IRQ_TIMERINT1, &integrator_timer_irq); + integrator_clocksource_init(reload * HZ / 1000); + integrator_clockevent_init(reload * HZ / 1000, ctrl); }