From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752690AbaCFKho (ORCPT ); Thu, 6 Mar 2014 05:37:44 -0500 Received: from terminus.zytor.com ([198.137.202.10]:44133 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751545AbaCFKhl (ORCPT ); Thu, 6 Mar 2014 05:37:41 -0500 Date: Thu, 6 Mar 2014 02:37:20 -0800 From: tip-bot for Stefan Agner Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, tglx@linutronix.de, shawn.guo@linaro.org, stefan@agner.ch Reply-To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, stefan@agner.ch, shawn.guo@linaro.org In-Reply-To: References: To: linux-tip-commits@vger.kernel.org Subject: [tip:timers/urgent] clocksource: vf_pit_timer: use complement for sched_clock reading Git-Commit-ID: 224aa3ed45c8735ae02bb2ecca002409fa6aa772 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 224aa3ed45c8735ae02bb2ecca002409fa6aa772 Gitweb: http://git.kernel.org/tip/224aa3ed45c8735ae02bb2ecca002409fa6aa772 Author: Stefan Agner AuthorDate: Wed, 5 Mar 2014 23:11:08 +0100 Committer: Thomas Gleixner CommitDate: Thu, 6 Mar 2014 11:34:14 +0100 clocksource: vf_pit_timer: use complement for sched_clock reading Vybrids PIT register is monitonic decreasing. However, sched_clock reading needs to be monitonic increasing. Use bitwise not to get the complement of the clock register. This fixes the clock going backward. Also, the clock now starts at 0 since we load the register with the maximum value at start. Signed-off-by: Stefan Agner Acked-by: Shawn Guo Cc: daniel.lezcano@linaro.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux@arm.linux.org.uk Link: http://lkml.kernel.org/r/d25af915993aec1b486be653eb86f748ddef54fe.1394057313.git.stefan@agner.ch Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner --- drivers/clocksource/vf_pit_timer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/clocksource/vf_pit_timer.c b/drivers/clocksource/vf_pit_timer.c index 02821b0..a918bc4 100644 --- a/drivers/clocksource/vf_pit_timer.c +++ b/drivers/clocksource/vf_pit_timer.c @@ -54,7 +54,7 @@ static inline void pit_irq_acknowledge(void) static u64 pit_read_sched_clock(void) { - return __raw_readl(clksrc_base + PITCVAL); + return ~__raw_readl(clksrc_base + PITCVAL); } static int __init pit_clocksource_init(unsigned long rate)