[PATCH V2 3/3] ARM: tegra114: cpuidle: add powered-down state

Joseph Lo josephl at nvidia.com
Wed Jun 12 22:13:39 EDT 2013

On Thu, 2013-06-13 at 01:41 +0800, Stephen Warren wrote:
> On 06/04/2013 03:40 PM, Daniel Lezcano wrote:
> > On 06/04/2013 12:48 PM, Joseph Lo wrote:
> >> This supports CPU core power down on each CPU when CPU idle. When CPU go
> >> into this state, it saves it's context and needs a proper configuration
> >> in flow controller to power gate the CPU when CPU runs into WFI
> >> instruction. And the CPU also needs to set the IRQ as CPU power down idle
> >> wake up event in flow controller.
> >>
> >> Signed-off-by: Joseph Lo <josephl at nvidia.com>
> > 
> > I would like to understand why there is a WARN with the
> > CPUIDLE_FLAG_TIMER_STOP flag set before queuing this patch and ensure it
> > is not the tree hiding the forest.
> Joseph, are you planning to post an updated series or respond to resolve
> Daniel's question?

I need more time to investigate the detail about what caused the WARN
when apply the flag. And what's the difference if we didn't enable
CLOCK_EVT_NOTIFY_BROADCAST_ON on CPU0. Why if I am moving the
clockevent_notify of CLOCK_EVT_NOTIFY_BROADCAST_EXIT before
"local_irq_enable" in the
"cpuidle_enter_state" (drivers/cpuidle/cpuidle.c), then the warning
message gone?


Because I need more time to figure it out, are you OK if I can post
another patch to apply CPUIDLE_FLAG_TIMER_STOP flag for all Tegra CPU
Idle drivers later? (Once we know what's the problem behind this)


I don't have an update of this series, if Daniel is OK if I can post
another patch to apply TIMER_STOP flag for all Tegra idle drivers.


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