2014-01-08 21:38:13

by Arnd Bergmann

[permalink] [raw]
Subject: Re: [PATCH v2 0/9] CPU enable method based SMP/hotplug + MSM conversion

On Tuesday 24 December 2013, Stephen Boyd wrote:
> This is a rework of patches sent a months back by Rohit[1].
> The goal of these patches is to add support for SMP and (basic)
> hotplug on MSM based SoCs. To get there, we add support for a
> generic way to hook in SMP/hotplug support code based on DT. To
> show how it's used, we convert the MSM8660 SMP support code over
> to the new method. After that we add support for the rest of the
> upstream MSM SoCs (note these patches are piled high on top of
> Rohit's patches to add 8074 support to MSM[2] and my follow ups[3,4],
> but this should only matter to the MSM maintainers).
>
> This is one of the last items of code that still requires us to have
> a mach directory and a machine descriptor. We should be able to move
> the hotplug/smp code out of mach directories if this approach is
> accepted.

The implementation looks ok to me, but I wonder whether on a global
scale we want to tie it more closely to the cpuidle implementations.
We already have a drivers/cpuidle framework, and while I admit
that I'm not familiar with the code in there, I would assume that
the smp operations and the cpuidle code usually go hand in hand.

Arnd


2014-01-09 01:50:24

by Stephen Boyd

[permalink] [raw]
Subject: Re: [PATCH v2 0/9] CPU enable method based SMP/hotplug + MSM conversion

On 01/08/14 13:37, Arnd Bergmann wrote:
> On Tuesday 24 December 2013, Stephen Boyd wrote:
>> This is a rework of patches sent a months back by Rohit[1].
>> The goal of these patches is to add support for SMP and (basic)
>> hotplug on MSM based SoCs. To get there, we add support for a
>> generic way to hook in SMP/hotplug support code based on DT. To
>> show how it's used, we convert the MSM8660 SMP support code over
>> to the new method. After that we add support for the rest of the
>> upstream MSM SoCs (note these patches are piled high on top of
>> Rohit's patches to add 8074 support to MSM[2] and my follow ups[3,4],
>> but this should only matter to the MSM maintainers).
>>
>> This is one of the last items of code that still requires us to have
>> a mach directory and a machine descriptor. We should be able to move
>> the hotplug/smp code out of mach directories if this approach is
>> accepted.
> The implementation looks ok to me, but I wonder whether on a global
> scale we want to tie it more closely to the cpuidle implementations.
> We already have a drivers/cpuidle framework, and while I admit
> that I'm not familiar with the code in there, I would assume that
> the smp operations and the cpuidle code usually go hand in hand.

Sure. Right now the smp ops code is fairly well tied into the arch layer
so it sounds like there is some future work when we move this stuff out
of the mach directory.

Would arm-soc be able to pick these patches up for 3.14? I think
everything is in place for these patches now that Mark has reviewed them.

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2014-01-23 22:04:38

by Kumar Gala

[permalink] [raw]
Subject: Re: [PATCH v2 0/9] CPU enable method based SMP/hotplug + MSM conversion


On Jan 8, 2014, at 7:50 PM, Stephen Boyd <[email protected]> wrote:

> On 01/08/14 13:37, Arnd Bergmann wrote:
>> On Tuesday 24 December 2013, Stephen Boyd wrote:
>>> This is a rework of patches sent a months back by Rohit[1].
>>> The goal of these patches is to add support for SMP and (basic)
>>> hotplug on MSM based SoCs. To get there, we add support for a
>>> generic way to hook in SMP/hotplug support code based on DT. To
>>> show how it's used, we convert the MSM8660 SMP support code over
>>> to the new method. After that we add support for the rest of the
>>> upstream MSM SoCs (note these patches are piled high on top of
>>> Rohit's patches to add 8074 support to MSM[2] and my follow ups[3,4],
>>> but this should only matter to the MSM maintainers).
>>>
>>> This is one of the last items of code that still requires us to have
>>> a mach directory and a machine descriptor. We should be able to move
>>> the hotplug/smp code out of mach directories if this approach is
>>> accepted.
>> The implementation looks ok to me, but I wonder whether on a global
>> scale we want to tie it more closely to the cpuidle implementations.
>> We already have a drivers/cpuidle framework, and while I admit
>> that I'm not familiar with the code in there, I would assume that
>> the smp operations and the cpuidle code usually go hand in hand.
>
> Sure. Right now the smp ops code is fairly well tied into the arch layer
> so it sounds like there is some future work when we move this stuff out
> of the mach directory.
>
> Would arm-soc be able to pick these patches up for 3.14? I think
> everything is in place for these patches now that Mark has reviewed them.

Ping, wondering if arm-soc would pick up:

ARM: Introduce CPU_METHOD_OF_DECLARE() for cpu hotplug/smp

The other patches are all msm specific so we can handle them through the normal channels.

- k

--
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