Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1479874

[PATCH v4 3/3] clocksource: timer-atmel-pit: simplify IRQ handler

Path csiph.com!1.us.feeder.erje.net!feeder.erje.net!2.eu.feeder.erje.net!news.szaf.org!news.unit0.net!news.panservice.it!bofh.it!news.nic.it!robomod
From Alexandre Belloni <alexandre.belloni@free-electrons.com>
Newsgroups linux.kernel
Subject [PATCH v4 3/3] clocksource: timer-atmel-pit: simplify IRQ handler
Date Fri, 09 Sep 2016 13:20:01 +0200
Message-ID <sfs0F-27K-11@gated-at.bofh.it> (permalink)
References <sfs0F-27K-13@gated-at.bofh.it>
X-Mailer git-send-email 2.9.3
Sender robomod@news.nic.it
List-ID <linux-kernel.vger.kernel.org>
X-Mailing-List linux-kernel@vger.kernel.org
Approved robomod@news.nic.it
Lines 35
Organization linux.* mail to news gateway
X-Original-Cc 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>
X-Original-Date Fri, 9 Sep 2016 13:13:50 +0200
X-Original-Message-ID <20160909111350.27534-4-alexandre.belloni@free-electrons.com>
X-Original-References <20160909111350.27534-1-alexandre.belloni@free-electrons.com>
X-Original-Sender linux-kernel-owner@vger.kernel.org
Xref csiph.com linux.kernel:1479874

Show key headers only | View raw


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 91cf04704ed1..6555821bbdae 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;
 	}
-- 
2.9.3

Back to linux.kernel | Previous | Next | Find similar | Unroll thread


Thread

[PATCH v4 3/3] clocksource: timer-atmel-pit: simplify IRQ handler Alexandre Belloni <alexandre.belloni@free-electrons.com> - 2016-09-09 13:20 +0200

csiph-web