From eea8e326ff476e418b99b6daa97f9bd85ac6c523 Mon Sep 17 00:00:00 2001 From: Shawn Guo Date: Thu, 6 Dec 2012 22:54:41 +0800 Subject: [PATCH] ARM: imx: return zero in case next event gets a large increment The return of v2_set_next_event() will lead to an infinite loop in tick_handle_oneshot_broadcast() - "goto again;" with imx6q WAIT mode (to be enabled). This happens because when global event did not expire any CPU local events, the broadcast device will be rearmed to a CPU local next_event, which could be far away from now and result in a max_delta_tick programming in set_next_event(). Fix the problem by detecting those next events with increments larger than 0x7fffffff, and simply return zero in that case. It leaves mx1_2_set_next_event() unchanged since only v2_set_next_event() will be running with imx6q WAIT mode support. Thanks Russell King for helping understand the problem. Signed-off-by: Shawn Guo --- arch/arm/mach-imx/time.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/arm/mach-imx/time.c b/arch/arm/mach-imx/time.c index f017302f6d09..5d7eb482efd3 100644 --- a/arch/arm/mach-imx/time.c +++ b/arch/arm/mach-imx/time.c @@ -152,7 +152,8 @@ static int v2_set_next_event(unsigned long evt, __raw_writel(tcmp, timer_base + V2_TCMP); - return (int)(tcmp - __raw_readl(timer_base + V2_TCN)) < 0 ? + return evt < 0x7fffffff && + (int)(tcmp - __raw_readl(timer_base + V2_TCN)) < 0 ? -ETIME : 0; }