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ARM: Integrator: convert to generic clockevent support

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Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Russell King 2010-01-15 21:49:23 +00:00
parent b9cedda230
commit 13edd86d7a
2 changed files with 78 additions and 38 deletions
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1
arch/arm/Kconfig
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@ -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.

115
arch/arm/mach-integrator/core.c
View File

@ -20,6 +20,7 @@
#include <linux/amba/bus.h>
#include <linux/amba/serial.h>
#include <linux/clocksource.h>
#include <linux/clockchips.h>
#include <linux/io.h>
#include <asm/clkdev.h>
@ -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);
}