Re: [Patch v2 2/4] driver: cpuidle: cpuidle-big-little: init driver for Exynos5420

From: Chander Kashyap
Date: Thu Apr 24 2014 - 03:47:17 EST


On 23 April 2014 22:02, Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> wrote:
> On Wed, Apr 23, 2014 at 10:25:52AM +0100, Chander Kashyap wrote:
>> Add "samsung,exynos5420" compatible string to initialize generic
>> big-little cpuidle driver for Exynos5420.
>>
>> Signed-off-by: Chander Kashyap <chander.kashyap@xxxxxxxxxx>
>> Signed-off-by: Chander Kashyap <k.chander@xxxxxxxxxxx>
>> Acked-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
>> ---
>> drivers/cpuidle/cpuidle-big_little.c | 3 ++-
>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/cpuidle/cpuidle-big_little.c b/drivers/cpuidle/cpuidle-big_little.c
>> index b45fc62..d0fac53 100644
>> --- a/drivers/cpuidle/cpuidle-big_little.c
>> +++ b/drivers/cpuidle/cpuidle-big_little.c
>> @@ -170,7 +170,8 @@ static int __init bl_idle_init(void)
>> /*
>> * Initialize the driver just for a compliant set of machines
>> */
>> - if (!of_machine_is_compatible("arm,vexpress,v2p-ca15_a7"))
>> + if (!of_machine_is_compatible("arm,vexpress,v2p-ca15_a7") &&
>> + (!of_machine_is_compatible("samsung,exynos5420")))
>> return -ENODEV;
>
> We should handle the string matching differently, we can't keep adding
> comparisons.

yes, that's true.


>
> Daniel raised the point already: what about the idle tables (data and
> number of states ?). TC2 has just a cluster state, and specific
> latencies, which are highly unlikely to be correct for this platform.
>

As of now only support for one state i.e. core power down.

As latencies are concerned, need to fine tune.

Thanks again for the review.

> Lorenzo
>



--
with warm regards,
Chander Kashyap
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