mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Alexandre Belloni <alexandre.belloni@free-electrons.com>
To: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>,
	Boris Brezillon <boris.brezillon@free-electrons.com>,
	Nicolas Ferre <nicolas.ferre@atmel.com>,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org,
	Alexandre Belloni <alexandre.belloni@free-electrons.com>
Subject: [PATCH v3 4/4] clocksource: timer-atmel-pit: simplify IRQ handler
Date: Tue, 23 Aug 2016 10:44:05 +0200	[thread overview]
Message-ID: <1471941845-24813-5-git-send-email-alexandre.belloni@free-electrons.com> (raw)
In-Reply-To: <1471941845-24813-1-git-send-email-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>
---
 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 633a94429842..2e215e8e6c1d 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;
 	}
-- 
2.8.1

      parent reply	other threads:[~2016-08-23  8:56 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-08-23  8:44 [PATCH v3 0/4] clocksource: timer-atmel-pit: driver fix and cleanups Alexandre Belloni
2016-08-23  8:44 ` [PATCH v3 1/4] clocksource: timer-atmel-pit: enable mck Alexandre Belloni
2016-08-23 13:52   ` Daniel Lezcano
2016-08-23  8:44 ` [PATCH v3 2/4] clocksource: timer-atmel-pit: drop at91sam926x_pit_common_init Alexandre Belloni
2016-08-23  8:44 ` [PATCH v3 3/4] clocksource: timer-atmel-pit: remove uselesss WARN_ON_ONCE Alexandre Belloni
2016-08-23  8:44 ` Alexandre Belloni [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1471941845-24813-5-git-send-email-alexandre.belloni@free-electrons.com \
    --to=alexandre.belloni@free-electrons.com \
    --cc=boris.brezillon@free-electrons.com \
    --cc=daniel.lezcano@linaro.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=nicolas.ferre@atmel.com \
    --cc=tglx@linutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®