Subject: [PATCH 02/17][V2] ARM: OMAP4: cpuidle - Declare the states with the driver declaration

From: [email-masked] (Daniel Lezcano)
Date: Tue, 24 Apr 2012 00:11:46 +0200

On 04/23/2012 07:08 PM, Kevin Hilman wrote:
> Daniel Lezcano<[email-masked]>  writes:
>
>> On 04/19/2012 03:58 PM, Daniel Lezcano wrote:
>>> On 04/10/2012 12:37 AM, Kevin Hilman wrote:
>>>> Daniel Lezcano<[email-masked]>   writes:
>>>>
>>>>> The cpuidle API allows to declare statically the states in the driver
>>>>> structure. Let's use it.
>>>>> We do no longer need the fill_cstate function called at runtime and
>>>>> by the way adding more instructions at boot time.
>>>>>
>>>>> Signed-off-by: Daniel Lezcano<[email-masked]>
>>>>> Reviewed-by: Jean Pihet<[email-masked]>
>>>>> Reviewed-by: Santosh Shilimkar<[email-masked]>
>>>>> ---
>>>>>    arch/arm/mach-omap2/cpuidle44xx.c |   57
>>>>> +++++++++++++++++++++---------------
>>>>>    1 files changed, 33 insertions(+), 24 deletions(-)
>>>>>
>>>>> diff --git a/arch/arm/mach-omap2/cpuidle44xx.c
>>>>> b/arch/arm/mach-omap2/cpuidle44xx.c
>>>>> index ee0bc50..6d86b59 100644
>>>>> --- a/arch/arm/mach-omap2/cpuidle44xx.c
>>>>> +++ b/arch/arm/mach-omap2/cpuidle44xx.c
>>>>> @@ -132,21 +132,39 @@ struct cpuidle_driver omap4_idle_driver = {
>>>>>        .name                = "omap4_idle",
>>>>>        .owner                = THIS_MODULE,
>>>>>        .en_core_tk_irqen        = 1,
>>>>> +    .states = {
>>>>> +        {
>>>>> +            /* C1 - CPU0 ON + CPU1 ON + MPU ON */
>>>>> +            .exit_latency = 2 + 2,
>>>>> +            .target_residency = 5,
>>>>> +            .flags = CPUIDLE_FLAG_TIME_VALID,
>>>>> +            .enter = omap4_enter_idle,
>>>>> +            .name = "C1",
>>>>> +            .desc = "MPUSS ON"
>>>>> +        },
>>>>> +        {
>>>>> +                        /* C2 - CPU0 OFF + CPU1 OFF + MPU CSWR */
>>>>> +            .exit_latency = 328 + 440,
>>>>> +            .target_residency = 960,
>>>>> +            .flags = CPUIDLE_FLAG_TIME_VALID,
>>>>> +            .enter = omap4_enter_idle,
>>>>> +            .name = "C2",
>>>>> +            .desc = "MPUSS CSWR",
>>>>> +        },
>>>>> +        {
>>>>> +            /* C3 - CPU0 OFF + CPU1 OFF + MPU OSWR */
>>>>> +            .exit_latency = 460 + 518,
>>>>> +            .target_residency = 1100,
>>>>> +            .flags = CPUIDLE_FLAG_TIME_VALID,
>>>>> +            .enter = omap4_enter_idle,
>>>>> +            .name = "C3",
>>>>> +            .desc = "MPUSS OSWR",
>>>>> +        },
>>>>> +    },
>>>>> +    .state_count = OMAP4_NUM_STATES,
>>>>
>>>> I think you can drop OMAP4_NUM_STATES here, and just use:
>>>>
>>>>      .state_count = ARRAY_SIZE(omap4_idle_driver.states),
>>>>
>>>> Then drop OMAP4_NUM_STATES all together in patch 3.
>>>
>>> Ok.
>>
>> I said 'ok' but it is not :)
>>
>> omap4_idle_driver.states has a fixed length which is CPUIDLE_STATE_MAX (8).
>> We need to define it manually as 3 for now.
>
> I don't see the connection between the two.
>
> Why can't you use ARRAY_SIZE(), and just have an error check later in
> the init to see if state_count>  max.

Maybe I misunderstood but you say:

.state_count = ARRAY_SIZE(omap4_idle_driver.states),

As in the cpuidle structure, the state array is CPUIDLE_STATE_MAX, 
ARRAY_SIZE will always return 8, not the number of the initialized states.

Anyway, I modified the patchset to use ARRAY_SIZE on the omap4_idle_data 
array, so we have:

.state_count = ARRAY_SIZE(omap4_idle_data),

   -- Daniel

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