Re: Broken cpuidle on PM branch?

[Kevin Hilman <khilman@deeprootsystems.com>]

Eduardo Valentin <eduardo.valentin@nokia.com> writes:

> On Tue, Oct 13, 2009 at 06:25:17PM +0200, ext Kevin Hilman wrote:
>> Eduardo Valentin <eduardo.valentin@nokia.com> writes:
>> 
>> > Hello Amit,
>> >
>> > On Mon, Oct 12, 2009 at 09:23:47PM +0200, ext Amit Kucheria wrote:
>> >> Hi,
>> >> 
>> >> I am testing twl4030 script optimisations on the current PM branch. But I am
>> >> seeing the board (RX51) freeze when CPU_IDLE is enabled in the config.
>> >> 
>> >> Is it known to work on other boards?
>> >
>> > I'm actually seeing this same behavior. But the board actually does not
>> > freeze. If you keep a key pressed of send a sysrq through serial line
>> > then you eventually get it back.
>> >
>> > It seams to be something related to serial driver and wakeup ?
>> >
>> 
>> Do you see this problem after doing
>> 
>>   # echo 1 > /debug/pm_debug/sleep_while_idle
>> 
>
> No I don't. The problem is gone it seams.
>
> similar effect happens if we
>
> # echo 0 > /sys/devices/platform/serial8250.2/sleep_timeout
>
> Of course, this would prevent device go to sleep I guess.
>

Yes, there is a problem with UART3 (in PER) going idle independently
of CORE/MPU that I have not yet found.

Kevin