Re: [PATCH 7/9] ARM: OMAP4+: Move the CPU wakeup prepare code under smp_prepare_cpus()

Santosh Shilimkar
2013-03-28T12:08:19Z

On Thursday 28 March 2013 05:34 PM, Russell King - ARM Linux wrote:
> On Thu, Mar 28, 2013 at 03:28:12PM +0530, Santosh Shilimkar wrote:
>> On Thursday 28 March 2013 03:16 PM, Russell King - ARM Linux wrote:
>>> On Thu, Mar 28, 2013 at 12:34:50AM +0530, Santosh Shilimkar wrote:
>>>> On Thursday 28 March 2013 12:15 AM, Kevin Hilman wrote:
>>>>> Santosh Shilimkar <santosh.shilimkar@ti.com> writes:
>>>>>
>>>>>> Move the secondary CPU wakeup prepare code under smp_prepare_cpus().
>>>>>
>>>>> Why?
>>>>>
>>>> Because that code belongs to smp_prepare_cpus(). As I said
>>>> in earlier patches, it was remainder of the pen release code
>>>> which was borrowed from ARM code initially.
>>>
>>> What about hotplug after the system is suspended? Is this setup
>>> preserved by the secure ROM?
>>>
>>> If not, it really needs to be part of the CPU bringup, not the
>>> boot-time-only preparation code.
>>>
>> Its already the case. Hotplug CPU restarts just like CPU bring-up.
>> Initial code, hotplug cpu and last cpu(suspend) were taking identical
>> path for the suspend wakeup. Later you suggested after the discussion
>> that hotplug CPU state need not be saved and can be restarted just like
>> the CPU bring-up path.
>>
>> So the current code follows above.
>
> smp_prepare_cpus() doesn't get run apart from at initial boot.
>
> So, I repeat my question: what restores OMAP_AUX_CORE_BOOT_1 after
> context loss?
>
Sorry I missed your point. OMAP_AUX_CORE_BOOT_* registers
are maintained across power transitions.

Regards,
Santosh