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ARM: gemini: Use timer1 for clockevent

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Use timer1 as clockevent timer.
The old driver uses timer2, which has some issues to setup

Signed-off-by: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
This commit is contained in:
Hans Ulli Kroll 2015-08-11 22:09:04 +02:00 committed by Olof Johansson
parent 570ceed4e2
commit 5dc9073988
1 changed files with 60 additions and 34 deletions
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94
arch/arm/mach-gemini/time.c
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@ -67,19 +67,11 @@ static int gemini_timer_set_next_event(unsigned long cycles,
{
u32 cr;
cr = readl(TIMER_CR);
/* This may be overdoing it, feel free to test without this */
cr &= ~TIMER_2_CR_ENABLE;
cr &= ~TIMER_2_CR_INT;
writel(cr, TIMER_CR);
/* Set next event */
writel(cycles, TIMER_COUNT(TIMER2_BASE));
writel(cycles, TIMER_LOAD(TIMER2_BASE));
cr |= TIMER_2_CR_ENABLE;
cr |= TIMER_2_CR_INT;
writel(cr, TIMER_CR);
/* Setup the match register */
cr = readl(TIMER_COUNT(TIMER1_BASE));
writel(cr + cycles, TIMER_MATCH1(TIMER1_BASE));
if (readl(TIMER_COUNT(TIMER1_BASE)) - cr > cycles)
return -ETIME;
return 0;
}
@ -92,10 +84,26 @@ static int gemini_timer_shutdown(struct clock_event_device *evt)
* Disable also for oneshot: the set_next() call will arm the timer
* instead.
*/
/* Stop timer and interrupt. */
cr = readl(TIMER_CR);
cr &= ~TIMER_2_CR_ENABLE;
cr &= ~TIMER_2_CR_INT;
cr &= ~(TIMER_1_CR_ENABLE | TIMER_1_CR_INT);
writel(cr, TIMER_CR);
/* Setup counter start from 0 */
writel(0, TIMER_COUNT(TIMER1_BASE));
writel(0, TIMER_LOAD(TIMER1_BASE));
/* enable interrupt */
cr = readl(TIMER_INTR_MASK);
cr &= ~(TIMER_1_INT_OVERFLOW | TIMER_1_INT_MATCH2);
cr |= TIMER_1_INT_MATCH1;
writel(cr, TIMER_INTR_MASK);
/* start the timer */
cr = readl(TIMER_CR);
cr |= TIMER_1_CR_ENABLE;
writel(cr, TIMER_CR);
return 0;
}
@ -104,21 +112,37 @@ static int gemini_timer_set_periodic(struct clock_event_device *evt)
u32 period = DIV_ROUND_CLOSEST(tick_rate, HZ);
u32 cr;
/* Start the timer */
writel(period, TIMER_COUNT(TIMER2_BASE));
writel(period, TIMER_LOAD(TIMER2_BASE));
/* Stop timer and interrupt */
cr = readl(TIMER_CR);
cr |= TIMER_2_CR_ENABLE;
cr |= TIMER_2_CR_INT;
cr &= ~(TIMER_1_CR_ENABLE | TIMER_1_CR_INT);
writel(cr, TIMER_CR);
/* Setup timer to fire at 1/HT intervals. */
cr = 0xffffffff - (period - 1);
writel(cr, TIMER_COUNT(TIMER1_BASE));
writel(cr, TIMER_LOAD(TIMER1_BASE));
/* enable interrupt on overflow */
cr = readl(TIMER_INTR_MASK);
cr &= ~(TIMER_1_INT_MATCH1 | TIMER_1_INT_MATCH2);
cr |= TIMER_1_INT_OVERFLOW;
writel(cr, TIMER_INTR_MASK);
/* Start the timer */
cr = readl(TIMER_CR);
cr |= TIMER_1_CR_ENABLE;
cr |= TIMER_1_CR_INT;
writel(cr, TIMER_CR);
return 0;
}
/* Use TIMER2 as clock event */
/* Use TIMER1 as clock event */
static struct clock_event_device gemini_clockevent = {
.name = "TIMER2",
.name = "TIMER1",
/* Reasonably fast and accurate clock event */
.rating = 300,
.shift = 32,
.features = CLOCK_EVT_FEAT_PERIODIC |
CLOCK_EVT_FEAT_ONESHOT,
.set_next_event = gemini_timer_set_next_event,
@ -175,20 +199,22 @@ void __init gemini_timer_init(void)
}
/*
* Make irqs happen for the system timer
* Reset the interrupt mask and status
*/
setup_irq(IRQ_TIMER2, &gemini_timer_irq);
writel(TIMER_INT_ALL_MASK, TIMER_INTR_MASK);
writel(0, TIMER_INTR_STATE);
writel(TIMER_DEFAULT_FLAGS, TIMER_CR);
/* Enable and use TIMER1 as clock source */
writel(0xffffffff, TIMER_COUNT(TIMER1_BASE));
writel(0xffffffff, TIMER_LOAD(TIMER1_BASE));
writel(TIMER_1_CR_ENABLE, TIMER_CR);
if (clocksource_mmio_init(TIMER_COUNT(TIMER1_BASE),
"TIMER1", tick_rate, 300, 32,
clocksource_mmio_readl_up))
pr_err("timer: failed to initialize gemini clock source\n");
/* Configure and register the clockevent */
/*
* Setup clockevent timer (interrupt-driven.)
*/
writel(0, TIMER_COUNT(TIMER1_BASE));
writel(0, TIMER_LOAD(TIMER1_BASE));
writel(0, TIMER_MATCH1(TIMER1_BASE));
writel(0, TIMER_MATCH2(TIMER1_BASE));
setup_irq(IRQ_TIMER1, &gemini_timer_irq);
gemini_clockevent.cpumask = cpumask_of(0);
clockevents_config_and_register(&gemini_clockevent, tick_rate,
1, 0xffffffff);
}