[PATCH 6/6] ARM: EXYNOS: Register cpuidle device only on Exynos4210 and 5250

Kukjin Kim kgene.kim at samsung.com
Thu Jul 10 06:30:05 PDT 2014


Bartlomiej Zolnierkiewicz wrote:
> 
> Hi,
> 
Hi Bart,

> On Tuesday, July 08, 2014 11:15:21 PM Kukjin Kim wrote:
> > Tomasz Figa wrote:
> > >
> > > Currently, the Exynos cpuidle driver works correctly only on Exynos4210
> > > and 5250. Trying to use it with just one CPU online on any other Exynos
> > > SoC will lead to system failure, due to unsupported AFTR mode on other
> > > SoCs. This patch fixes the problem by registering the driver only on
> > > supported SoCs and letting others simply use default WFI mode until
> > > support for them is added.
> > >
> > Hmm...I thought other SoCs have no problem on cpuidle except exynos5420 and
> > exynos5440....something like this would be helpful to avoid system failure.
> > But unfortunately this conflicts with Pankaj's cleanup cpufreq_init() and
> > cpuidle_init() patch you've reviewed and I've applied in my local...
> >
> > I'm going to check which exynos is ok on cpuidle and then sort them out.
> 
> Tomasz's patch is correct - currently only Exynos4210 and Exynos5250 work
> fine with AFTR mode and upstream kernel (AFTR gets triggered by offlining
> CPUs other than CPU0).
> 
> [ Exynos4x12 and Exynos3250 need secure firmware support (patches for this
>   need to be reworked on top of recent PM/firmware/cpuidle changes).
> 
>   Exynos5410 should use big_little cpuidle driver. ]
> 
Agreed that this is required at this moment.
I will take this into fixes for 3.16.

Thanks,
Kukjin




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