[v5,5/6] exynos: cpuidle: do not allow cpuidle registration for Exynos5420

Message ID 1400054637-21505-6-git-send-email-chander.kashyap@linaro.org
State New
Headers show

Commit Message

Chander Kashyap May 14, 2014, 8:03 a.m.
Exynos5420 is big.Little Soc. It uses cpuidle-big-litle generic cpuidle driver.
Hence do not allow exynos cpuidle driver registration for Exynos5420.

Signed-off-by: Chander Kashyap <chander.kashyap@linaro.org>
Signed-off-by: Chander Kashyap <k.chander@samsung.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 arch/arm/mach-exynos/cpuidle.c |    3 +++
 1 file changed, 3 insertions(+)

Comments

Tomasz Figa May 15, 2014, 9:26 p.m. | #1
Hi Chander,

On 14.05.2014 10:03, Chander Kashyap wrote:
> Exynos5420 is big.Little Soc. It uses cpuidle-big-litle generic cpuidle driver.
> Hence do not allow exynos cpuidle driver registration for Exynos5420.
> 
> Signed-off-by: Chander Kashyap <chander.kashyap@linaro.org>
> Signed-off-by: Chander Kashyap <k.chander@samsung.com>
> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> ---
>  arch/arm/mach-exynos/cpuidle.c |    3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
> index 3dd385e..807a386 100644
> --- a/arch/arm/mach-exynos/cpuidle.c
> +++ b/arch/arm/mach-exynos/cpuidle.c
> @@ -218,6 +218,9 @@ static int exynos_cpuidle_probe(struct platform_device *pdev)
>  	int cpu_id, ret;
>  	struct cpuidle_device *device;
>  
> +	if (soc_is_exynos5420())
> +		return -ENODEV;
> +
>  	if (soc_is_exynos5250())
>  		exynos5_core_down_clk();
>  
> 

Why not put this in exynos.c in exynos_dt_machine_init(), so
exynos_cpuidle_init() is called only if not running on Exynos5420?

Best regards,
Tomasz
--
To unsubscribe from this list: send the line "unsubscribe linux-pm" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Chander Kashyap May 16, 2014, 4:01 a.m. | #2
Hi Tomasz,

On 16 May 2014 02:56, Tomasz Figa <tomasz.figa@gmail.com> wrote:
> Hi Chander,
>
> On 14.05.2014 10:03, Chander Kashyap wrote:
>> Exynos5420 is big.Little Soc. It uses cpuidle-big-litle generic cpuidle driver.
>> Hence do not allow exynos cpuidle driver registration for Exynos5420.
>>
>> Signed-off-by: Chander Kashyap <chander.kashyap@linaro.org>
>> Signed-off-by: Chander Kashyap <k.chander@samsung.com>
>> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
>> ---
>>  arch/arm/mach-exynos/cpuidle.c |    3 +++
>>  1 file changed, 3 insertions(+)
>>
>> diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
>> index 3dd385e..807a386 100644
>> --- a/arch/arm/mach-exynos/cpuidle.c
>> +++ b/arch/arm/mach-exynos/cpuidle.c
>> @@ -218,6 +218,9 @@ static int exynos_cpuidle_probe(struct platform_device *pdev)
>>       int cpu_id, ret;
>>       struct cpuidle_device *device;
>>
>> +     if (soc_is_exynos5420())
>> +             return -ENODEV;
>> +
>>       if (soc_is_exynos5250())
>>               exynos5_core_down_clk();
>>
>>
>
> Why not put this in exynos.c in exynos_dt_machine_init(), so
> exynos_cpuidle_init() is called only if not running on Exynos5420?
>

That makes more sense.
I will update this

Thanks
> Best regards,
> Tomasz
Chander Kashyap May 16, 2014, 8:03 a.m. | #3
Exynos5420 is a big-little Soc from Samsung. It has 4 A15 and 4 A7 cores.

This patchset adds cpuidle support for Exynos5420 SoC based on
generic big.little cpuidle driver.

Tested on SMDK5420.

This patch set depends on:
	1. [PATCH 0/5] MCPM backend for Exynos5420
	   http://www.spinics.net/lists/arm-kernel/msg331100.html
Changelog is in respective patches.
Chander Kashyap (5):
  driver: cpuidle-big-little: add of_device_id structure
  arm: exynos: add generic function to calculate cpu number
  cpuidle: config: Add ARCH_EXYNOS entry to select cpuidle-big-little
    driver
  driver: cpuidle: cpuidle-big-little: init driver for Exynos5420
  exynos: cpuidle: do not allow cpuidle registration for Exynos5420
  mcpm: exynos: populate suspend and powered_up callbacks

 arch/arm/mach-exynos/exynos.c        |    4 +++-
 arch/arm/mach-exynos/mcpm-exynos.c   |   36 ++++++++++++++++++++++++++++++++++
 arch/arm/mach-exynos/regs-pmu.h      |    9 +++++++++
 drivers/cpuidle/Kconfig.arm          |    2 +-
 drivers/cpuidle/cpuidle-big_little.c |   12 +++++++++++-
 5 files changed, 60 insertions(+), 3 deletions(-)
Chander Kashyap May 19, 2014, 5:40 a.m. | #4
Hi Daniel/Kgene,

On 16 May 2014 13:33, Chander Kashyap <chander.kashyap@linaro.org> wrote:
> Exynos5420 is a big-little Soc from Samsung. It has 4 A15 and 4 A7 cores.
>
> This patchset adds cpuidle support for Exynos5420 SoC based on
> generic big.little cpuidle driver.
>
> Tested on SMDK5420.
>
> This patch set depends on:
>         1. [PATCH 0/5] MCPM backend for Exynos5420
>            http://www.spinics.net/lists/arm-kernel/msg331100.html
> Changelog is in respective patches.
> Chander Kashyap (5):
>   driver: cpuidle-big-little: add of_device_id structure
>   arm: exynos: add generic function to calculate cpu number
>   cpuidle: config: Add ARCH_EXYNOS entry to select cpuidle-big-little
>     driver
>   driver: cpuidle: cpuidle-big-little: init driver for Exynos5420
>   exynos: cpuidle: do not allow cpuidle registration for Exynos5420
>   mcpm: exynos: populate suspend and powered_up callbacks
>
>  arch/arm/mach-exynos/exynos.c        |    4 +++-
>  arch/arm/mach-exynos/mcpm-exynos.c   |   36 ++++++++++++++++++++++++++++++++++
>  arch/arm/mach-exynos/regs-pmu.h      |    9 +++++++++
>  drivers/cpuidle/Kconfig.arm          |    2 +-
>  drivers/cpuidle/cpuidle-big_little.c |   12 +++++++++++-
>  5 files changed, 60 insertions(+), 3 deletions(-)
>
> --
> 1.7.9.5
>

As dependency patches are merged. If their are no further comment, can
these patches be taken?
Chander Kashyap May 26, 2014, 4:40 a.m. | #5
On 19 May 2014 11:10, Chander Kashyap <chander.kashyap@linaro.org> wrote:
> Hi Daniel/Kgene,
>
> On 16 May 2014 13:33, Chander Kashyap <chander.kashyap@linaro.org> wrote:
>> Exynos5420 is a big-little Soc from Samsung. It has 4 A15 and 4 A7 cores.
>>
>> This patchset adds cpuidle support for Exynos5420 SoC based on
>> generic big.little cpuidle driver.
>>
>> Tested on SMDK5420.
>>
>> This patch set depends on:
>>         1. [PATCH 0/5] MCPM backend for Exynos5420
>>            http://www.spinics.net/lists/arm-kernel/msg331100.html
>> Changelog is in respective patches.
>> Chander Kashyap (5):
>>   driver: cpuidle-big-little: add of_device_id structure
>>   arm: exynos: add generic function to calculate cpu number
>>   cpuidle: config: Add ARCH_EXYNOS entry to select cpuidle-big-little
>>     driver
>>   driver: cpuidle: cpuidle-big-little: init driver for Exynos5420
>>   exynos: cpuidle: do not allow cpuidle registration for Exynos5420
>>   mcpm: exynos: populate suspend and powered_up callbacks
>>
>>  arch/arm/mach-exynos/exynos.c        |    4 +++-
>>  arch/arm/mach-exynos/mcpm-exynos.c   |   36 ++++++++++++++++++++++++++++++++++
>>  arch/arm/mach-exynos/regs-pmu.h      |    9 +++++++++
>>  drivers/cpuidle/Kconfig.arm          |    2 +-
>>  drivers/cpuidle/cpuidle-big_little.c |   12 +++++++++++-
>>  5 files changed, 60 insertions(+), 3 deletions(-)
>>
>> --
>> 1.7.9.5
>>
>
> As dependency patches are merged. If their are no further comment, can
> these patches be taken?
>

ping

> --
> with warm regards,
> Chander Kashyap
Tomasz Figa May 26, 2014, 10:29 a.m. | #6
Hi Chander,

On 16.05.2014 10:03, Chander Kashyap wrote:
> Exynos5420 is a big-little Soc from Samsung. It has 4 A15 and 4 A7 cores.
> 
> This patchset adds cpuidle support for Exynos5420 SoC based on
> generic big.little cpuidle driver.
> 
> Tested on SMDK5420.
> 
> This patch set depends on:
> 	1. [PATCH 0/5] MCPM backend for Exynos5420
> 	   http://www.spinics.net/lists/arm-kernel/msg331100.html
> Changelog is in respective patches.
> Chander Kashyap (5):
>   driver: cpuidle-big-little: add of_device_id structure
>   arm: exynos: add generic function to calculate cpu number
>   cpuidle: config: Add ARCH_EXYNOS entry to select cpuidle-big-little
>     driver
>   driver: cpuidle: cpuidle-big-little: init driver for Exynos5420
>   exynos: cpuidle: do not allow cpuidle registration for Exynos5420
>   mcpm: exynos: populate suspend and powered_up callbacks
> 
>  arch/arm/mach-exynos/exynos.c        |    4 +++-
>  arch/arm/mach-exynos/mcpm-exynos.c   |   36 ++++++++++++++++++++++++++++++++++
>  arch/arm/mach-exynos/regs-pmu.h      |    9 +++++++++
>  drivers/cpuidle/Kconfig.arm          |    2 +-
>  drivers/cpuidle/cpuidle-big_little.c |   12 +++++++++++-
>  5 files changed, 60 insertions(+), 3 deletions(-)
> 

For the whole series,

Reviewed-by: Tomasz Figa <t.figa@samsung.com>

Best regards,
Tomasz
--
To unsubscribe from this list: send the line "unsubscribe linux-pm" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Chander Kashyap May 28, 2014, 4:28 a.m. | #7
On 26 May 2014 15:59, Tomasz Figa <tomasz.figa@gmail.com> wrote:
> Hi Chander,
>
> On 16.05.2014 10:03, Chander Kashyap wrote:
>> Exynos5420 is a big-little Soc from Samsung. It has 4 A15 and 4 A7 cores.
>>
>> This patchset adds cpuidle support for Exynos5420 SoC based on
>> generic big.little cpuidle driver.
>>
>> Tested on SMDK5420.
>>
>> This patch set depends on:
>>       1. [PATCH 0/5] MCPM backend for Exynos5420
>>          http://www.spinics.net/lists/arm-kernel/msg331100.html
>> Changelog is in respective patches.
>> Chander Kashyap (5):
>>   driver: cpuidle-big-little: add of_device_id structure
>>   arm: exynos: add generic function to calculate cpu number
>>   cpuidle: config: Add ARCH_EXYNOS entry to select cpuidle-big-little
>>     driver
>>   driver: cpuidle: cpuidle-big-little: init driver for Exynos5420
>>   exynos: cpuidle: do not allow cpuidle registration for Exynos5420
>>   mcpm: exynos: populate suspend and powered_up callbacks
>>
>>  arch/arm/mach-exynos/exynos.c        |    4 +++-
>>  arch/arm/mach-exynos/mcpm-exynos.c   |   36 ++++++++++++++++++++++++++++++++++
>>  arch/arm/mach-exynos/regs-pmu.h      |    9 +++++++++
>>  drivers/cpuidle/Kconfig.arm          |    2 +-
>>  drivers/cpuidle/cpuidle-big_little.c |   12 +++++++++++-
>>  5 files changed, 60 insertions(+), 3 deletions(-)
>>
>
> For the whole series,
>
> Reviewed-by: Tomasz Figa <t.figa@samsung.com>

Thanks Tomasz.

Dear Kukjin,
Can you take these patches.
>
> Best regards,
> Tomasz
Kukjin Kim May 28, 2014, 4:35 a.m. | #8
Chander Kashyap wrote:
> 
> On 26 May 2014 15:59, Tomasz Figa <tomasz.figa@gmail.com> wrote:
> > Hi Chander,
> >
> > On 16.05.2014 10:03, Chander Kashyap wrote:
> >> Exynos5420 is a big-little Soc from Samsung. It has 4 A15 and 4 A7
> cores.
> >>
> >> This patchset adds cpuidle support for Exynos5420 SoC based on
> >> generic big.little cpuidle driver.
> >>
> >> Tested on SMDK5420.
> >>
> >> This patch set depends on:
> >>       1. [PATCH 0/5] MCPM backend for Exynos5420
> >>          http://www.spinics.net/lists/arm-kernel/msg331100.html
> >> Changelog is in respective patches.
> >> Chander Kashyap (5):
> >>   driver: cpuidle-big-little: add of_device_id structure
> >>   arm: exynos: add generic function to calculate cpu number
> >>   cpuidle: config: Add ARCH_EXYNOS entry to select cpuidle-big-little
> >>     driver
> >>   driver: cpuidle: cpuidle-big-little: init driver for Exynos5420
> >>   exynos: cpuidle: do not allow cpuidle registration for Exynos5420
> >>   mcpm: exynos: populate suspend and powered_up callbacks
> >>
> >>  arch/arm/mach-exynos/exynos.c        |    4 +++-
> >>  arch/arm/mach-exynos/mcpm-exynos.c   |   36
> ++++++++++++++++++++++++++++++++++
> >>  arch/arm/mach-exynos/regs-pmu.h      |    9 +++++++++
> >>  drivers/cpuidle/Kconfig.arm          |    2 +-
> >>  drivers/cpuidle/cpuidle-big_little.c |   12 +++++++++++-
> >>  5 files changed, 60 insertions(+), 3 deletions(-)
> >>
> >
> > For the whole series,
> >
> > Reviewed-by: Tomasz Figa <t.figa@samsung.com>
> 
> Thanks Tomasz.
> 
> Dear Kukjin,
> Can you take these patches.
> >
When I looked at this series quickly, looks good to me but I need to get ack from cpuidle maintainer Rafael or Daniel.

Thanks,
Kukjin

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/
Daniel Lezcano May 28, 2014, 9:02 a.m. | #9
On 05/28/2014 06:35 AM, Kukjin Kim wrote:
> Chander Kashyap wrote:
>>
>> On 26 May 2014 15:59, Tomasz Figa <tomasz.figa@gmail.com> wrote:
>>> Hi Chander,
>>>
>>> On 16.05.2014 10:03, Chander Kashyap wrote:
>>>> Exynos5420 is a big-little Soc from Samsung. It has 4 A15 and 4 A7
>> cores.
>>>>
>>>> This patchset adds cpuidle support for Exynos5420 SoC based on
>>>> generic big.little cpuidle driver.
>>>>
>>>> Tested on SMDK5420.
>>>>
>>>> This patch set depends on:
>>>>        1. [PATCH 0/5] MCPM backend for Exynos5420
>>>>           http://www.spinics.net/lists/arm-kernel/msg331100.html
>>>> Changelog is in respective patches.
>>>> Chander Kashyap (5):
>>>>    driver: cpuidle-big-little: add of_device_id structure
>>>>    arm: exynos: add generic function to calculate cpu number
>>>>    cpuidle: config: Add ARCH_EXYNOS entry to select cpuidle-big-little
>>>>      driver
>>>>    driver: cpuidle: cpuidle-big-little: init driver for Exynos5420
>>>>    exynos: cpuidle: do not allow cpuidle registration for Exynos5420
>>>>    mcpm: exynos: populate suspend and powered_up callbacks
>>>>
>>>>   arch/arm/mach-exynos/exynos.c        |    4 +++-
>>>>   arch/arm/mach-exynos/mcpm-exynos.c   |   36
>> ++++++++++++++++++++++++++++++++++
>>>>   arch/arm/mach-exynos/regs-pmu.h      |    9 +++++++++
>>>>   drivers/cpuidle/Kconfig.arm          |    2 +-
>>>>   drivers/cpuidle/cpuidle-big_little.c |   12 +++++++++++-
>>>>   5 files changed, 60 insertions(+), 3 deletions(-)
>>>>
>>>
>>> For the whole series,
>>>
>>> Reviewed-by: Tomasz Figa <t.figa@samsung.com>
>>
>> Thanks Tomasz.
>>
>> Dear Kukjin,
>> Can you take these patches.
>>>
> When I looked at this series quickly, looks good to me but I need to get ack from cpuidle maintainer Rafael or Daniel.

Acked the different cpuidle bits.

Thanks
   -- Daniel
Chander Kashyap May 29, 2014, 4:37 a.m. | #10
On 28 May 2014 14:32, Daniel Lezcano <daniel.lezcano@linaro.org> wrote:
> On 05/28/2014 06:35 AM, Kukjin Kim wrote:
>>
>> Chander Kashyap wrote:
>>>
>>>
>>> On 26 May 2014 15:59, Tomasz Figa <tomasz.figa@gmail.com> wrote:
>>>>
>>>> Hi Chander,
>>>>
>>>> On 16.05.2014 10:03, Chander Kashyap wrote:
>>>>>
>>>>> Exynos5420 is a big-little Soc from Samsung. It has 4 A15 and 4 A7
>>>
>>> cores.
>>>>>
>>>>>
>>>>> This patchset adds cpuidle support for Exynos5420 SoC based on
>>>>> generic big.little cpuidle driver.
>>>>>
>>>>> Tested on SMDK5420.
>>>>>
>>>>> This patch set depends on:
>>>>>        1. [PATCH 0/5] MCPM backend for Exynos5420
>>>>>           http://www.spinics.net/lists/arm-kernel/msg331100.html
>>>>> Changelog is in respective patches.
>>>>> Chander Kashyap (5):
>>>>>    driver: cpuidle-big-little: add of_device_id structure
>>>>>    arm: exynos: add generic function to calculate cpu number
>>>>>    cpuidle: config: Add ARCH_EXYNOS entry to select cpuidle-big-little
>>>>>      driver
>>>>>    driver: cpuidle: cpuidle-big-little: init driver for Exynos5420
>>>>>    exynos: cpuidle: do not allow cpuidle registration for Exynos5420
>>>>>    mcpm: exynos: populate suspend and powered_up callbacks
>>>>>
>>>>>   arch/arm/mach-exynos/exynos.c        |    4 +++-
>>>>>   arch/arm/mach-exynos/mcpm-exynos.c   |   36
>>>
>>> ++++++++++++++++++++++++++++++++++
>>>>>
>>>>>   arch/arm/mach-exynos/regs-pmu.h      |    9 +++++++++
>>>>>   drivers/cpuidle/Kconfig.arm          |    2 +-
>>>>>   drivers/cpuidle/cpuidle-big_little.c |   12 +++++++++++-
>>>>>   5 files changed, 60 insertions(+), 3 deletions(-)
>>>>>
>>>>
>>>> For the whole series,
>>>>
>>>> Reviewed-by: Tomasz Figa <t.figa@samsung.com>
>>>
>>>
>>> Thanks Tomasz.
>>>
>>> Dear Kukjin,
>>> Can you take these patches.
>>>>
>>>>
>> When I looked at this series quickly, looks good to me but I need to get
>> ack from cpuidle maintainer Rafael or Daniel.
>
>
> Acked the different cpuidle bits.

Hi Kukjin,
Can you take it now?


>
> Thanks
>   -- Daniel
>
>
> --
>  <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs
>
> Follow Linaro:  <http://www.facebook.com/pages/Linaro> Facebook |
> <http://twitter.com/#!/linaroorg> Twitter |
> <http://www.linaro.org/linaro-blog/> Blog
>
Chander Mohan Kashyap June 10, 2014, 12:38 p.m. | #11
On Thu, May 29, 2014 at 10:07 AM, Chander Kashyap
<chander.kashyap@linaro.org> wrote:
> On 28 May 2014 14:32, Daniel Lezcano <daniel.lezcano@linaro.org> wrote:
>> On 05/28/2014 06:35 AM, Kukjin Kim wrote:
>>>
>>> Chander Kashyap wrote:
>>>>
>>>>
>>>> On 26 May 2014 15:59, Tomasz Figa <tomasz.figa@gmail.com> wrote:
>>>>>
>>>>> Hi Chander,
>>>>>
>>>>> On 16.05.2014 10:03, Chander Kashyap wrote:
>>>>>>
>>>>>> Exynos5420 is a big-little Soc from Samsung. It has 4 A15 and 4 A7
>>>>
>>>> cores.
>>>>>>
>>>>>>
>>>>>> This patchset adds cpuidle support for Exynos5420 SoC based on
>>>>>> generic big.little cpuidle driver.
>>>>>>
>>>>>> Tested on SMDK5420.
>>>>>>
>>>>>> This patch set depends on:
>>>>>>        1. [PATCH 0/5] MCPM backend for Exynos5420
>>>>>>           http://www.spinics.net/lists/arm-kernel/msg331100.html
>>>>>> Changelog is in respective patches.
>>>>>> Chander Kashyap (5):
>>>>>>    driver: cpuidle-big-little: add of_device_id structure
>>>>>>    arm: exynos: add generic function to calculate cpu number
>>>>>>    cpuidle: config: Add ARCH_EXYNOS entry to select cpuidle-big-little
>>>>>>      driver
>>>>>>    driver: cpuidle: cpuidle-big-little: init driver for Exynos5420
>>>>>>    exynos: cpuidle: do not allow cpuidle registration for Exynos5420
>>>>>>    mcpm: exynos: populate suspend and powered_up callbacks
>>>>>>
>>>>>>   arch/arm/mach-exynos/exynos.c        |    4 +++-
>>>>>>   arch/arm/mach-exynos/mcpm-exynos.c   |   36
>>>>
>>>> ++++++++++++++++++++++++++++++++++
>>>>>>
>>>>>>   arch/arm/mach-exynos/regs-pmu.h      |    9 +++++++++
>>>>>>   drivers/cpuidle/Kconfig.arm          |    2 +-
>>>>>>   drivers/cpuidle/cpuidle-big_little.c |   12 +++++++++++-
>>>>>>   5 files changed, 60 insertions(+), 3 deletions(-)
>>>>>>
>>>>>
>>>>> For the whole series,
>>>>>
>>>>> Reviewed-by: Tomasz Figa <t.figa@samsung.com>
>>>>
>>>>
>>>> Thanks Tomasz.
>>>>
>>>> Dear Kukjin,
>>>> Can you take these patches.
>>>>>
>>>>>
>>> When I looked at this series quickly, looks good to me but I need to get
>>> ack from cpuidle maintainer Rafael or Daniel.
>>
>>
>> Acked the different cpuidle bits.
>
> Hi Kukjin,
> Can you take it now?

ping
Sorry for previous html messages.

>
>
>>
>> Thanks
>>   -- Daniel
>>
>>
>> --
>>  <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs
>>
>> Follow Linaro:  <http://www.facebook.com/pages/Linaro> Facebook |
>> <http://twitter.com/#!/linaroorg> Twitter |
>> <http://www.linaro.org/linaro-blog/> Blog
>>
>
>
>
> --
> with warm regards,
> Chander Kashyap

Patch

diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
index 3dd385e..807a386 100644
--- a/arch/arm/mach-exynos/cpuidle.c
+++ b/arch/arm/mach-exynos/cpuidle.c
@@ -218,6 +218,9 @@  static int exynos_cpuidle_probe(struct platform_device *pdev)
 	int cpu_id, ret;
 	struct cpuidle_device *device;
 
+	if (soc_is_exynos5420())
+		return -ENODEV;
+
 	if (soc_is_exynos5250())
 		exynos5_core_down_clk();