[PATCH 09/12] ARM: shmobile: r8a7740: Add Suspend-To-RAM A3SM

Bastian Hecht hechtb at gmail.com
Tue Jun 4 11:34:30 EDT 2013


Hi Simon,

quite some effort has gone into this patch. People from ARM Ltd. have
discussed issues about the shutdown in other threads and I spent quite
some time on it. What are the problems? Are we concerned about the
stability of our system? The CPUIdle feature shut down my r8a7740 on
the Armadillo board more than 1 million times successfully. Further
CPUIdle is deselected as default config anyway. And single
suspend/resume cycles should be even less problematic.

Thanks,

 Bastian


2013/6/4 Simon Horman <horms at verge.net.au>:
> On Mon, May 27, 2013 at 08:50:19PM -0700, Olof Johansson wrote:
>> Hi,
>>
>> On Mon, May 27, 2013 at 05:59:50PM +0900, Simon Horman wrote:
>> > From: Bastian Hecht <hechtb at gmail.com>
>> >
>> > We add 2 Suspend to RAM modes:
>> > - A3SM PLL0 on/off:     Power domain A3SM that contains the ARM core
>> >                         and the 2nd level cache with either PLL0 on
>> >                         or off
>> >
>> > As the suspend to memory mechanism we use A3SM PLL off. A3SM PLL on
>> > is included here too, so CPUIdle can use both power down modes (not
>> > included in this patch).
>> >
>> > The setup of the SYSC regarding the external IRQs is taken from
>> > pm-sh7372.c from Magnus Damm.
>> >
>> > Signed-off-by: Bastian Hecht <hechtb+renesas at gmail.com>
>>
>> Missing S-o-b from you, Simon?
>>
>> > +   .text
>> > +ENTRY(v7_cpu_resume)
>> > +   bl      v7_invalidate_l1
>> > +   b       cpu_resume
>> > +ENDPROC(v7_cpu_resume)
>>
>> This is a global namespace so it'll conflict with i.MX whenever
>> you multiplatform enable shmobile. Might want to pick a more
>> unique name.
>
> I have decided to drop this and related cpuidle and suspend-to-ram
> patches for r8a7740 after discussion with Magnus.



More information about the linux-arm-kernel mailing list