From fc686d0037d782c994e338ecb01bfef8bbafff9f Mon Sep 17 00:00:00 2001 From: Daniel Lezcano Date: Mon, 24 Aug 2015 15:14:30 +0200 Subject: [PATCH] clockevents/drivers/mtk: Fix spurious interrupt leading to crash 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 50f0641c65b6..c8badc427eec 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); -- 2.20.1