From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752338AbcD1NVH (ORCPT ); Thu, 28 Apr 2016 09:21:07 -0400 Received: from mail-wm0-f43.google.com ([74.125.82.43]:38402 "EHLO mail-wm0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751829AbcD1NVF (ORCPT ); Thu, 28 Apr 2016 09:21:05 -0400 From: Daniel Lezcano To: tglx@linutronix.de, mingo@kernel.org Cc: Jisheng Zhang , linux-kernel@vger.kernel.org (open list:CLOCKSOURCE, CLOC...) Subject: [PATCH 1/5] clockevents/drivers/dw_apb_timer: Implement ->set_state_oneshot_stopped() Date: Thu, 28 Apr 2016 15:20:44 +0200 Message-Id: <1461849648-12751-1-git-send-email-daniel.lezcano@linaro.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <20160428131908.GC5197@linaro.org> References: <20160428131908.GC5197@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jisheng Zhang The dw_apb_timer only "supports PERIODIC mode and their drivers emulate ONESHOT over that" as described in commit 8fff52fd5093 ("clockevents: Introduce CLOCK_EVT_STATE_ONESHOT_STOPPED state"). Inspired by Viresh, I think the dw_apb_timer also needs to implement the set_state_oneshot_stopped() which is called by the clkevt core, when the next event is required at an expiry time of 'KTIME_MAX'. This normally happens with NO_HZ_{IDLE|FULL} in both LOWRES/HIGHRES modes. This patch makes the clockevent device to stop on such an event, to avoid spurious interrupts, as explained by the above commit. Signed-off-by: Jisheng Zhang Signed-off-by: Daniel Lezcano Reviewed-by: Viresh Kumar --- drivers/clocksource/dw_apb_timer.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/clocksource/dw_apb_timer.c b/drivers/clocksource/dw_apb_timer.c index 6334526..797505a 100644 --- a/drivers/clocksource/dw_apb_timer.c +++ b/drivers/clocksource/dw_apb_timer.c @@ -264,6 +264,7 @@ dw_apb_clockevent_init(int cpu, const char *name, unsigned rating, dw_ced->ced.set_state_shutdown = apbt_shutdown; dw_ced->ced.set_state_periodic = apbt_set_periodic; dw_ced->ced.set_state_oneshot = apbt_set_oneshot; + dw_ced->ced.set_state_oneshot_stopped = apbt_shutdown; dw_ced->ced.tick_resume = apbt_resume; dw_ced->ced.set_next_event = apbt_next_event; dw_ced->ced.irq = dw_ced->timer.irq; -- 1.9.1