Re: PM: off mode

[Kevin Hilman <khilman@deeprootsystems.com>]

Roger Quadros <ext-roger.quadros@nokia.com> writes:

> Roger Quadros wrote:
>> ext Roger Quadros wrote:
>>> ext Kevin Hilman wrote:
>>>> Roger Quadros <ext-roger.quadros@nokia.com> writes:
>>>>
>>>>> ext Roger Quadros wrote:
>>>>>> ext Kevin Hilman wrote:
>>>>>>> Roger Quadros <ext-roger.quadros@nokia.com> writes:
>>>>>>>
>>>>>>>> Hi Kevin,
>>>>>>>>
>>>>>>>>  Off mode does not seem to work on RX51 on latest PM branch. I get a
>>>>>>>> reboot if I set enable_off_mode and sleep_while_idle and I wait for
>>>>>>>> timeout.
>>>>>>>>
>>>>>>>>  Does it work on other platforms?
>>>>>>>>
>>>>>>> Yes, I tested on SDP, omap3evm, Beagle, Overo and RX51.
>>>>>>>
>>>>>>> On RX51, I'm using omap3_pm_defconfig with the debug UART changed to
>>>>>>> UART3 and things work fine here.
>>>>>>>
>>>>>>> I using rootfs from latest fiasco image, and it drops me into
>>>>>>> an early
>>>>>>> shell because /sbin/preinit fails in various ways. Note that
>>>>>>> I'm using
>>>>>>> an S2.0 GP board.  Note also that I modified /sbin/preinit to launch
>>>>>>> another getty on ttyS2 so I get a shell since newer kernels
>>>>>>> ignore the
>>>>>>> ATAGs passed by nolo.
>>>>>>>
>>>>>>> Below is a console log of my boot so you can see what is going on.
>>>>>>> Because /sbin/preinit enables off-mode and sleep_while_idle, I just
>>>>>>> let it boot and it seems to work.
>>>>>>>
>>>>>>> Kevin
>>>>>>>
>>>>>> I am having S2.1 board and it does not work on that. It gets locked
>>>>>> up and restarts after idle timeout.
>>>>>> But I checked that it works on S2.0 board.
>>>>>>
>>>>>> Any clue what could be the problem?
>>>>>>
>>>>>> -roger
>>>>>> -- 
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>>>>>>
>>>>> Kevin,
>>>>>
>>>>> I have some new observations.
>>>>>
>>>>> It works only if we load the kernel via USB. Instead, if we flash the
>>>>> kernel, it will not work even with S2.0 board. It boots to shell but
>>>>> after sleep timeout (5 seconds) console gets locked up and it reboots
>>>>> after a while.
>>>>
>>>> Roger,
>>>>
>>>> Does this happen even with the working defconfig you sent the other day?
>>>>
>>>> Kevin
>>>
>>> The config that i sent does not work with S2.0 hardware in either case.
>>> It works with S2.1 hardware only in one case i.e. kernel load via
>>> USB. It does not work if kernel is flashed.
>>> Also when my config is used on S2.1, core always remains in ON mode
>>> and never hits RET/OFF mode.
>>>
>>> -roger
>>
>> Kevin,
>>
>> I just found out that it has nothing to do with kernel load via USB
>> or not. I was using an initrd while USB load which used to change
>> vdd1 OPP, that's why it was working.
>>
>> So the final conclusion is, after boot to shell, if we change VDD1
>> OPP, then off mode works fine on my S2.0 HS board.
>>     e.g.
>>         echo 1 > /sys/power/vdd1_opp
>>         echo 1 > /sys/power/sleep_while_idle
>>         echo 1 > /sys/power/enable_off_mode
>>
>> It works on S2.1 board too except that garbage characters are
>> printed on console after idle timeout.
>>
>> Does this give any more clue to the problem?
>>
>> -roger
>>
>
> Hi Kevin,
>
> What compiler version do you use?
>

I currely use CSL 2008q3, but am switching to 2009q1-161

Kevin