From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932190AbbJSVDN (ORCPT ); Mon, 19 Oct 2015 17:03:13 -0400 Received: from mail-wi0-f181.google.com ([209.85.212.181]:35328 "EHLO mail-wi0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750876AbbJSU77 (ORCPT ); Mon, 19 Oct 2015 16:59:59 -0400 From: Daniel Lezcano To: tglx@linutronix.de Cc: linux-kernel@vger.kernel.org, mingo@kernel.org, Yingjoe Chen , Matthias Brugger , linux-arm-kernel@lists.infradead.org (moderated list:ARM/Mediatek SoC...), linux-mediatek@lists.infradead.org (moderated list:ARM/Mediatek SoC...) Subject: [PATCH 1/9] clockevents/drivers/mtk: Fix spurious interrupt leading to crash Date: Mon, 19 Oct 2015 22:59:20 +0200 Message-Id: <1445288368-6440-1-git-send-email-daniel.lezcano@linaro.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <56255943.6060807@linaro.org> References: <56255943.6060807@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org After analysis done by Yingjoe Chen, the timer appears to have a pending interrupt when it is enabled. Fix this by acknowledging the pending interrupt when enabling the timer interrupt. Signed-off-by: Daniel Lezcano Tested-by: Yingjoe Chen --- drivers/clocksource/mtk_timer.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) diff --git a/drivers/clocksource/mtk_timer.c b/drivers/clocksource/mtk_timer.c index 50f0641..c8badc4 100644 --- a/drivers/clocksource/mtk_timer.c +++ b/drivers/clocksource/mtk_timer.c @@ -141,14 +141,6 @@ static irqreturn_t mtk_timer_interrupt(int irq, void *dev_id) return IRQ_HANDLED; } -static void mtk_timer_global_reset(struct mtk_clock_event_device *evt) -{ - /* Disable all interrupts */ - writel(0x0, evt->gpt_base + GPT_IRQ_EN_REG); - /* Acknowledge all interrupts */ - writel(0x3f, evt->gpt_base + GPT_IRQ_ACK_REG); -} - static void mtk_timer_setup(struct mtk_clock_event_device *evt, u8 timer, u8 option) { @@ -168,6 +160,12 @@ static void mtk_timer_enable_irq(struct mtk_clock_event_device *evt, u8 timer) { u32 val; + /* Disable all interrupts */ + writel(0x0, evt->gpt_base + GPT_IRQ_EN_REG); + + /* Acknowledge all spurious pending interrupts */ + writel(0x3f, evt->gpt_base + GPT_IRQ_ACK_REG); + val = readl(evt->gpt_base + GPT_IRQ_EN_REG); writel(val | GPT_IRQ_ENABLE(timer), evt->gpt_base + GPT_IRQ_EN_REG); @@ -220,8 +218,6 @@ static void __init mtk_timer_init(struct device_node *node) } rate = clk_get_rate(clk); - mtk_timer_global_reset(evt); - if (request_irq(evt->dev.irq, mtk_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL, "mtk_timer", evt)) { pr_warn("failed to setup irq %d\n", evt->dev.irq); -- 1.9.1