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| author | Shawn Guo <shawn.guo@linaro.org> | 2012-12-06 18:54:41 +0400 |
|---|---|---|
| committer | Shawn Guo <shawn.guo@linaro.org> | 2013-01-30 17:08:08 +0400 |
| commit | eea8e326ff476e418b99b6daa97f9bd85ac6c523 (patch) | |
| tree | a7ee83da9e18f2c8e64b91cac8bf2864c2670327 /arch/arm/mach-imx/time.c | |
| parent | 1d7180e24e22a608cc4d7e8fd425a19a9394a7ed (diff) | |
| download | linux-eea8e326ff476e418b99b6daa97f9bd85ac6c523.tar.xz | |
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 <shawn.guo@linaro.org>
Diffstat (limited to 'arch/arm/mach-imx/time.c')
| -rw-r--r-- | arch/arm/mach-imx/time.c | 3 |
1 files changed, 2 insertions, 1 deletions
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; } |