On Monday, April 07, 2014 11:43:47 AM Daniel Lezcano wrote: > On 04/04/2014 06:09 PM, Bartlomiej Zolnierkiewicz wrote: > > > > On Friday, April 04, 2014 03:43:09 PM Daniel Lezcano wrote: > >> The cpuidle driver is broken since v3.11 and now we are at v3.14. > >> > >> Default the cpuidle driver to favorize a better detection next time. > >> > >> Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> > >> Reviewed-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx> > >> --- > >> arch/arm/configs/exynos_defconfig | 1 + > >> 1 file changed, 1 insertion(+) > >> > >> diff --git a/arch/arm/configs/exynos_defconfig b/arch/arm/configs/exynos_defconfig > >> index 4ce7b70..6ed4b34 100644 > >> --- a/arch/arm/configs/exynos_defconfig > >> +++ b/arch/arm/configs/exynos_defconfig > >> @@ -132,3 +132,4 @@ CONFIG_DEBUG_INFO=y > >> CONFIG_DEBUG_USER=y > >> CONFIG_CRYPTO_SHA256=y > >> CONFIG_CRC_CCITT=y > >> +CONFIG_CPU_IDLE=y > > > > Sorry but I have to NAK this change. There are three issues with AFTR > > mode that should be resolved first before this patch can be merged: > > > > * The upstream Exynos cpuidle code lacks support for secure firmware and > > it is used on i.e. Trats2 boards (Exynos4412). Attempts to use AFTR on > > such hardware results in oops + lockup. > > I have patches adding secure firmware support to Exynos cpuidle driver > > but they depend on Tomasz Figa's PM changes which are not yet upstream. > > Ok. > > > * Somebody needs to verify that the current Exynos cpuidle driver works > > in the AFTR mode on Exynos5420 for which support has been added recently > > (I really doubt it looking at some internal trees). > > Rajeshwari (cc'ed) is working on creating a big.Little driver for this > board, so it will be a separate cpuidle driver. > > > * Some of our u-boot bootloader versions are incompatible with AFTR. We > > have observed the problem happening on Trats board (Exynos4210) on which > > it can be fixed by using the upstream u-boot version and Universal C210 > > board (Exynos4210 with broken SMP support) on which there is no upstream > > u-boot available (IIRC) and because of the broken SMP support enabling > > cpuidle results in attempt to enter AFTR during boot + immediate lockup. > > > > I know that this is mainly our problem but the issue is widespread on > > our targets and I believe that adding some workaround for it in cpuidle > > core would be beneficial for the whole cpuidle subsystem. Namely there > > should be some way of telling cpuidle subsystem to either disable > > particular state(s) or limit the max available state. I think that this > > can be also useful for testing and development of other cpuidle drivers. > > > > For now please change this patch to add CONFIG_CPU_IDLE=n instead (since > > the config option is "default y" it will be auto-enabled if there is no > > entry in the defconfig).. > > Ok. > > Kukjin, is it possible you merge patches 1->16 ? It is OK given that patch #17 is fixed and merged at the same time (preferably it should go before patches #1-16 to preserve bisectability). Alternatively 'default y' should be removed from patch #16 before the merge. We really don't want to have EXYNOS cpuidle driver enabled by default yet. Best regards, -- Bartlomiej Zolnierkiewicz Samsung R&D Institute Poland Samsung Electronics -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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