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From: Daniel Lezcano <daniel.lezcano@linaro.org>
To: tglx@linutronix.de
Cc: mingo@kernel.org, linux-kernel@vger.kernel.org,
	Alexandre Belloni <alexandre.belloni@free-electrons.com>,
	Nicolas Ferre <nicolas.ferre@atmel.com>
Subject: [PATCH 8/9] clocksource/drivers/timer-atmel-pit: Simplify IRQ handler
Date: Mon, 12 Sep 2016 11:15:46 +0200	[thread overview]
Message-ID: <1473671747-9400-8-git-send-email-daniel.lezcano@linaro.org> (raw)
In-Reply-To: <1473671747-9400-1-git-send-email-daniel.lezcano@linaro.org>

From: Alexandre Belloni <alexandre.belloni@free-electrons.com>

Because the PIT is also a proper clocksource, the timekeeping code  is
already able to handle lost ticks.

Reported-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/timer-atmel-pit.c | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/drivers/clocksource/timer-atmel-pit.c b/drivers/clocksource/timer-atmel-pit.c
index 91cf047..6555821 100644
--- a/drivers/clocksource/timer-atmel-pit.c
+++ b/drivers/clocksource/timer-atmel-pit.c
@@ -152,15 +152,10 @@ static irqreturn_t at91sam926x_pit_interrupt(int irq, void *dev_id)
 	/* The PIT interrupt may be disabled, and is shared */
 	if (clockevent_state_periodic(&data->clkevt) &&
 	    (pit_read(data->base, AT91_PIT_SR) & AT91_PIT_PITS)) {
-		unsigned nr_ticks;
-
 		/* Get number of ticks performed before irq, and ack it */
-		nr_ticks = PIT_PICNT(pit_read(data->base, AT91_PIT_PIVR));
-		do {
-			data->cnt += data->cycle;
-			data->clkevt.event_handler(&data->clkevt);
-			nr_ticks--;
-		} while (nr_ticks);
+		data->cnt += data->cycle * PIT_PICNT(pit_read(data->base,
+							      AT91_PIT_PIVR));
+		data->clkevt.event_handler(&data->clkevt);
 
 		return IRQ_HANDLED;
 	}
-- 
2.7.4

  parent reply	other threads:[~2016-09-12  9:16 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-09-12  9:10 [PULL] clockevents for 4.9 Daniel Lezcano
2016-09-12  9:15 ` [PATCH 1/9] clocksource/drivers/moxart: Refactor enable/disable Daniel Lezcano
2016-09-12  9:15   ` [PATCH 2/9] clocksource/drivers/moxart: Use struct to hold state Daniel Lezcano
2016-09-12  9:15   ` [PATCH 3/9] clocksource/drivers/moxart: Add Aspeed support Daniel Lezcano
2016-09-12  9:15   ` [PATCH 4/9] clocksource/drivers/moxart: Replace setup_irq by request_irq Daniel Lezcano
2016-09-12  9:15   ` [PATCH 5/9] clocksource/drivers/moxart: Replace panic by pr_err Daniel Lezcano
2016-09-12  9:15   ` [PATCH 6/9] clocksource/drivers/timer-atmel-pit: Drop at91sam926x_pit_common_init Daniel Lezcano
2016-09-12  9:15   ` [PATCH 7/9] clocksource/drivers/timer-atmel-pit: Remove uselesss WARN_ON_ONCE Daniel Lezcano
2016-09-12  9:15   ` Daniel Lezcano [this message]
2016-09-12  9:15   ` [PATCH 9/9] clocksource/drivers/oxnas: Add OX820 compatible Daniel Lezcano

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