diff options
| author | Xianzhong <b07117@freescale.com> | 2013-12-18 22:02:07 +0800 |
|---|---|---|
| committer | Xianzhong <b07117@freescale.com> | 2014-01-21 22:02:35 +0800 |
| commit | 361dcf89276af5ad396757efc8f30b9c1c5f8846 (patch) | |
| tree | 2d21f12ee47785299a0407968c028d75aebbf6ca /arch | |
| parent | 6097eaa96e5f7d6609b69bdaae00d916446d6ac2 (diff) | |
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')
| -rw-r--r-- | arch/arm/plat-mxc/time.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/arm/plat-mxc/time.c b/arch/arm/plat-mxc/time.c index aaeedb66d66d..cf869f6e011b 100644 --- a/arch/arm/plat-mxc/time.c +++ b/arch/arm/plat-mxc/time.c @@ -165,7 +165,8 @@ static int v2_set_next_event(unsigned long evt, __raw_writel(tcmp, timer_base + V2_TCMP); - return 0; + return evt < 0x7fffffff && + (int)(tcmp - __raw_readl(timer_base + V2_TCN)) < 0 ? -ETIME : 0; } #ifdef DEBUG |