[RFC] [PATCH] ARM: save/restore power control register on Cortex-A9 suspend/resume

[Chander Kashyap]

On Tue, Jul 1, 2014 at 6:18 PM, Russell King - ARM Linux
<linux at arm.linux.org.uk> wrote:
> On Tue, Jul 01, 2014 at 06:15:49PM +0530, Chander Kashyap wrote:
>> The CP15 power register holds clock latency and dynamic clock gating settings
>> for Cortex-A9 processor, which lost during the suspend/resume. So it needs to
>> be saved/restored on suspend/resume.
>>
>> Signed-off-by: Chander Kashyap <k.chander at samsung.com>
>> ---
>>  It is depedent on: ARM: save/restore diagnostic register on Cortex-A9 suspend/resume
>>  http://www.spinics.net/lists/arm-kernel/msg340506.html
>>
>>  arch/arm/mm/proc-v7.S |    6 +++++-
>>  1 file changed, 5 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S
>> index e26bfaa..9905df5 100644
>> --- a/arch/arm/mm/proc-v7.S
>> +++ b/arch/arm/mm/proc-v7.S
>> @@ -163,12 +163,14 @@ ENDPROC(cpu_v7_do_resume)
>>       globl_equ       cpu_ca9mp_switch_mm,    cpu_v7_switch_mm
>>       globl_equ       cpu_ca9mp_set_pte_ext,  cpu_v7_set_pte_ext
>>  .globl       cpu_ca9mp_suspend_size
>> -.equ cpu_ca9mp_suspend_size, cpu_v7_suspend_size + 1 * 4
>> +.equ cpu_ca9mp_suspend_size, cpu_v7_suspend_size + 2 * 4
>>  #ifdef CONFIG_ARM_CPU_SUSPEND
>>  ENTRY(cpu_ca9mp_do_suspend)
>>       stmfd   sp!, {r4}
>>       mrc     p15, 0, r4, c15, c0, 1  @ Diagnostic register
>>       stmia   r0!, {r4}
>> +     mrc     p15, 0, r4, c15, c0, 0  @ Power register
>> +     stmia   r0!, {r4}
>>       ldmfd   sp!, {r4}
>
> Please combine these - yes, it'll be a larger change, but it'll be much
> better.

Are asking me to squash this patch with Shawn's patch?
If so i will do that.

>
>         stmfd   sp!, {r4-r5}
>         mrc     p15, 0, r4, c15, c0, 1  @ Diagnostic register
>         mrc     p15, 0, r5, c15, c0, 0  @ Power register
>         stmia   r0!, {r4-r5}
>         ldmfd   sp!, {r4-r5}
>
>
>>       b       cpu_v7_do_suspend
>>  ENDPROC(cpu_ca9mp_do_suspend)
>> @@ -176,6 +178,8 @@ ENDPROC(cpu_ca9mp_do_suspend)
>>  ENTRY(cpu_ca9mp_do_resume)
>>       ldmia   r0!, {r4}
>>       mcr     p15, 0, r4, c15, c0, 1  @ Diagnostic register
>> +     ldmia   r0!, {r4}
>> +     mcr     p15, 0, r4, c15, c0, 0  @ Power register
>
>         ldmia   r0!, {r4-r5}
>         mcr     p15, 0, r4, c15, c0, 1  @ Diagnostic register
>         mcr     p15, 0, r5, c15, c0, 0  @ Power register

I will do these changes


Thanks for the review.

>
>>       b       cpu_v7_do_resume
>>  ENDPROC(cpu_ca9mp_do_resume)
>>  #endif
>
> Thanks.
>
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