ARM: EXYNOS: cpu hotplug: use v7_exit_coherency_flush macro for cache disabling

Message ID 1398176280-7258-1-git-send-email-leela.krishna@linaro.org
State New
Headers show

Commit Message

Leela Krishna Amudala April 22, 2014, 2:18 p.m.
Remove the duplicated code for cache disabling and use "v7_exit_coherency_flush"
macro to do the same job.

Signed-off-by: Leela Krishna Amudala <leela.krishna@linaro.org>

---
cpu hotplug is tested with 3.15-rc1 on Origen(which has cortex A9) and
Arndale octa(which has cortex A7 and A15) boards.

 arch/arm/mach-exynos/hotplug.c |   56 ++--------------------------------------
 1 file changed, 2 insertions(+), 54 deletions(-)

Comments

Daniel Lezcano April 22, 2014, 2:36 p.m. | #1
On 04/22/2014 04:18 PM, Leela Krishna Amudala wrote:
> Remove the duplicated code for cache disabling and use "v7_exit_coherency_flush"
> macro to do the same job.

Hi Leela,

thanks for this patch! It would be nice if you can describe why those 
macros can be replaced by the generic v7_exit_coherency_flush macro.

>
> Signed-off-by: Leela Krishna Amudala <leela.krishna@linaro.org>
>
> ---
> cpu hotplug is tested with 3.15-rc1 on Origen(which has cortex A9) and
> Arndale octa(which has cortex A7 and A15) boards.
>
>   arch/arm/mach-exynos/hotplug.c |   56 ++--------------------------------------
>   1 file changed, 2 insertions(+), 54 deletions(-)
>
> diff --git a/arch/arm/mach-exynos/hotplug.c b/arch/arm/mach-exynos/hotplug.c
> index 5eead53..9eb8d1b 100644
> --- a/arch/arm/mach-exynos/hotplug.c
> +++ b/arch/arm/mach-exynos/hotplug.c
> @@ -24,56 +24,6 @@
>   #include "common.h"
>   #include "regs-pmu.h"
>
> -static inline void cpu_enter_lowpower_a9(void)
> -{
> -	unsigned int v;
> -
> -	asm volatile(
> -	"	mcr	p15, 0, %1, c7, c5, 0\n"
> -	"	mcr	p15, 0, %1, c7, c10, 4\n"
> -	/*
> -	 * Turn off coherency
> -	 */
> -	"	mrc	p15, 0, %0, c1, c0, 1\n"
> -	"	bic	%0, %0, %3\n"
> -	"	mcr	p15, 0, %0, c1, c0, 1\n"
> -	"	mrc	p15, 0, %0, c1, c0, 0\n"
> -	"	bic	%0, %0, %2\n"
> -	"	mcr	p15, 0, %0, c1, c0, 0\n"
> -	  : "=&r" (v)
> -	  : "r" (0), "Ir" (CR_C), "Ir" (0x40)
> -	  : "cc");
> -}
> -
> -static inline void cpu_enter_lowpower_a15(void)
> -{
> -	unsigned int v;
> -
> -	asm volatile(
> -	"	mrc	p15, 0, %0, c1, c0, 0\n"
> -	"	bic	%0, %0, %1\n"
> -	"	mcr	p15, 0, %0, c1, c0, 0\n"
> -	  : "=&r" (v)
> -	  : "Ir" (CR_C)
> -	  : "cc");
> -
> -	flush_cache_louis();
> -
> -	asm volatile(
> -	/*
> -	* Turn off coherency
> -	*/
> -	"	mrc	p15, 0, %0, c1, c0, 1\n"
> -	"	bic	%0, %0, %1\n"
> -	"	mcr	p15, 0, %0, c1, c0, 1\n"
> -	: "=&r" (v)
> -	: "Ir" (0x40)
> -	: "cc");
> -
> -	isb();
> -	dsb();
> -}
> -
>   static inline void cpu_leave_lowpower(void)
>   {
>   	unsigned int v;
> @@ -141,10 +91,8 @@ void __ref exynos_cpu_die(unsigned int cpu)
>   	 * appropriate sequence for entering low power.
>   	 */
>   	asm("mrc p15, 0, %0, c0, c0, 0" : "=r"(primary_part) : : "cc");

Can't you remove this asm line above as well as the primary_part variable ?

> -	if ((primary_part & 0xfff0) == 0xc0f0)
> -		cpu_enter_lowpower_a15();
> -	else
> -		cpu_enter_lowpower_a9();
> +
> +	v7_exit_coherency_flush(louis);
>
>   	platform_do_lowpower(cpu, &spurious);
>
>
Nicolas Pitre April 22, 2014, 6:14 p.m. | #2
On Tue, 22 Apr 2014, Leela Krishna Amudala wrote:

> Remove the duplicated code for cache disabling and use "v7_exit_coherency_flush"
> macro to do the same job.
> 
> Signed-off-by: Leela Krishna Amudala <leela.krishna@linaro.org>

Acked-by: Nicolas Pitre <nico@linaro.org>


> 
> ---
> cpu hotplug is tested with 3.15-rc1 on Origen(which has cortex A9) and
> Arndale octa(which has cortex A7 and A15) boards.
> 
>  arch/arm/mach-exynos/hotplug.c |   56 ++--------------------------------------
>  1 file changed, 2 insertions(+), 54 deletions(-)
> 
> diff --git a/arch/arm/mach-exynos/hotplug.c b/arch/arm/mach-exynos/hotplug.c
> index 5eead53..9eb8d1b 100644
> --- a/arch/arm/mach-exynos/hotplug.c
> +++ b/arch/arm/mach-exynos/hotplug.c
> @@ -24,56 +24,6 @@
>  #include "common.h"
>  #include "regs-pmu.h"
>  
> -static inline void cpu_enter_lowpower_a9(void)
> -{
> -	unsigned int v;
> -
> -	asm volatile(
> -	"	mcr	p15, 0, %1, c7, c5, 0\n"
> -	"	mcr	p15, 0, %1, c7, c10, 4\n"
> -	/*
> -	 * Turn off coherency
> -	 */
> -	"	mrc	p15, 0, %0, c1, c0, 1\n"
> -	"	bic	%0, %0, %3\n"
> -	"	mcr	p15, 0, %0, c1, c0, 1\n"
> -	"	mrc	p15, 0, %0, c1, c0, 0\n"
> -	"	bic	%0, %0, %2\n"
> -	"	mcr	p15, 0, %0, c1, c0, 0\n"
> -	  : "=&r" (v)
> -	  : "r" (0), "Ir" (CR_C), "Ir" (0x40)
> -	  : "cc");
> -}
> -
> -static inline void cpu_enter_lowpower_a15(void)
> -{
> -	unsigned int v;
> -
> -	asm volatile(
> -	"	mrc	p15, 0, %0, c1, c0, 0\n"
> -	"	bic	%0, %0, %1\n"
> -	"	mcr	p15, 0, %0, c1, c0, 0\n"
> -	  : "=&r" (v)
> -	  : "Ir" (CR_C)
> -	  : "cc");
> -
> -	flush_cache_louis();
> -
> -	asm volatile(
> -	/*
> -	* Turn off coherency
> -	*/
> -	"	mrc	p15, 0, %0, c1, c0, 1\n"
> -	"	bic	%0, %0, %1\n"
> -	"	mcr	p15, 0, %0, c1, c0, 1\n"
> -	: "=&r" (v)
> -	: "Ir" (0x40)
> -	: "cc");
> -
> -	isb();
> -	dsb();
> -}
> -
>  static inline void cpu_leave_lowpower(void)
>  {
>  	unsigned int v;
> @@ -141,10 +91,8 @@ void __ref exynos_cpu_die(unsigned int cpu)
>  	 * appropriate sequence for entering low power.
>  	 */
>  	asm("mrc p15, 0, %0, c0, c0, 0" : "=r"(primary_part) : : "cc");
> -	if ((primary_part & 0xfff0) == 0xc0f0)
> -		cpu_enter_lowpower_a15();
> -	else
> -		cpu_enter_lowpower_a9();
> +
> +	v7_exit_coherency_flush(louis);
>  
>  	platform_do_lowpower(cpu, &spurious);
>  
> -- 
> 1.7.9.5
> 
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Leela Krishna Amudala April 23, 2014, 5:44 a.m. | #3
Hi Daniel,

Thanks for reviewing the patch.

On Tue, Apr 22, 2014 at 8:06 PM, Daniel Lezcano
<daniel.lezcano@linaro.org> wrote:
> On 04/22/2014 04:18 PM, Leela Krishna Amudala wrote:
>>
>> Remove the duplicated code for cache disabling and use
>> "v7_exit_coherency_flush"
>> macro to do the same job.
>
>
> Hi Leela,
>
> thanks for this patch! It would be nice if you can describe why those macros
> can be replaced by the generic v7_exit_coherency_flush macro.
>

Okay, will give the description in commit message

>
>>
>> Signed-off-by: Leela Krishna Amudala <leela.krishna@linaro.org>
>>
>> ---
>> cpu hotplug is tested with 3.15-rc1 on Origen(which has cortex A9) and
>> Arndale octa(which has cortex A7 and A15) boards.
>>
>>   arch/arm/mach-exynos/hotplug.c |   56
>> ++--------------------------------------
>>   1 file changed, 2 insertions(+), 54 deletions(-)
>>
>> diff --git a/arch/arm/mach-exynos/hotplug.c
>> b/arch/arm/mach-exynos/hotplug.c
>> index 5eead53..9eb8d1b 100644
>> --- a/arch/arm/mach-exynos/hotplug.c
>> +++ b/arch/arm/mach-exynos/hotplug.c
>> @@ -24,56 +24,6 @@
>>   #include "common.h"
>>   #include "regs-pmu.h"
>>
>> -static inline void cpu_enter_lowpower_a9(void)
>> -{
>> -       unsigned int v;
>> -
>> -       asm volatile(
>> -       "       mcr     p15, 0, %1, c7, c5, 0\n"
>> -       "       mcr     p15, 0, %1, c7, c10, 4\n"
>> -       /*
>> -        * Turn off coherency
>> -        */
>> -       "       mrc     p15, 0, %0, c1, c0, 1\n"
>> -       "       bic     %0, %0, %3\n"
>> -       "       mcr     p15, 0, %0, c1, c0, 1\n"
>> -       "       mrc     p15, 0, %0, c1, c0, 0\n"
>> -       "       bic     %0, %0, %2\n"
>> -       "       mcr     p15, 0, %0, c1, c0, 0\n"
>> -         : "=&r" (v)
>> -         : "r" (0), "Ir" (CR_C), "Ir" (0x40)
>> -         : "cc");
>> -}
>> -
>> -static inline void cpu_enter_lowpower_a15(void)
>> -{
>> -       unsigned int v;
>> -
>> -       asm volatile(
>> -       "       mrc     p15, 0, %0, c1, c0, 0\n"
>> -       "       bic     %0, %0, %1\n"
>> -       "       mcr     p15, 0, %0, c1, c0, 0\n"
>> -         : "=&r" (v)
>> -         : "Ir" (CR_C)
>> -         : "cc");
>> -
>> -       flush_cache_louis();
>> -
>> -       asm volatile(
>> -       /*
>> -       * Turn off coherency
>> -       */
>> -       "       mrc     p15, 0, %0, c1, c0, 1\n"
>> -       "       bic     %0, %0, %1\n"
>> -       "       mcr     p15, 0, %0, c1, c0, 1\n"
>> -       : "=&r" (v)
>> -       : "Ir" (0x40)
>> -       : "cc");
>> -
>> -       isb();
>> -       dsb();
>> -}
>> -
>>   static inline void cpu_leave_lowpower(void)
>>   {
>>         unsigned int v;
>> @@ -141,10 +91,8 @@ void __ref exynos_cpu_die(unsigned int cpu)
>>          * appropriate sequence for entering low power.
>>          */
>>         asm("mrc p15, 0, %0, c0, c0, 0" : "=r"(primary_part) : : "cc");
>
>
> Can't you remove this asm line above as well as the primary_part variable ?

Didn't notice it, will remove this.

>
>
>> -       if ((primary_part & 0xfff0) == 0xc0f0)
>> -               cpu_enter_lowpower_a15();
>> -       else
>> -               cpu_enter_lowpower_a9();
>> +
>> +       v7_exit_coherency_flush(louis);
>>
>>         platform_do_lowpower(cpu, &spurious);
>>
>>
>
>
> --
>  <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs
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Patch

diff --git a/arch/arm/mach-exynos/hotplug.c b/arch/arm/mach-exynos/hotplug.c
index 5eead53..9eb8d1b 100644
--- a/arch/arm/mach-exynos/hotplug.c
+++ b/arch/arm/mach-exynos/hotplug.c
@@ -24,56 +24,6 @@ 
 #include "common.h"
 #include "regs-pmu.h"
 
-static inline void cpu_enter_lowpower_a9(void)
-{
-	unsigned int v;
-
-	asm volatile(
-	"	mcr	p15, 0, %1, c7, c5, 0\n"
-	"	mcr	p15, 0, %1, c7, c10, 4\n"
-	/*
-	 * Turn off coherency
-	 */
-	"	mrc	p15, 0, %0, c1, c0, 1\n"
-	"	bic	%0, %0, %3\n"
-	"	mcr	p15, 0, %0, c1, c0, 1\n"
-	"	mrc	p15, 0, %0, c1, c0, 0\n"
-	"	bic	%0, %0, %2\n"
-	"	mcr	p15, 0, %0, c1, c0, 0\n"
-	  : "=&r" (v)
-	  : "r" (0), "Ir" (CR_C), "Ir" (0x40)
-	  : "cc");
-}
-
-static inline void cpu_enter_lowpower_a15(void)
-{
-	unsigned int v;
-
-	asm volatile(
-	"	mrc	p15, 0, %0, c1, c0, 0\n"
-	"	bic	%0, %0, %1\n"
-	"	mcr	p15, 0, %0, c1, c0, 0\n"
-	  : "=&r" (v)
-	  : "Ir" (CR_C)
-	  : "cc");
-
-	flush_cache_louis();
-
-	asm volatile(
-	/*
-	* Turn off coherency
-	*/
-	"	mrc	p15, 0, %0, c1, c0, 1\n"
-	"	bic	%0, %0, %1\n"
-	"	mcr	p15, 0, %0, c1, c0, 1\n"
-	: "=&r" (v)
-	: "Ir" (0x40)
-	: "cc");
-
-	isb();
-	dsb();
-}
-
 static inline void cpu_leave_lowpower(void)
 {
 	unsigned int v;
@@ -141,10 +91,8 @@  void __ref exynos_cpu_die(unsigned int cpu)
 	 * appropriate sequence for entering low power.
 	 */
 	asm("mrc p15, 0, %0, c0, c0, 0" : "=r"(primary_part) : : "cc");
-	if ((primary_part & 0xfff0) == 0xc0f0)
-		cpu_enter_lowpower_a15();
-	else
-		cpu_enter_lowpower_a9();
+
+	v7_exit_coherency_flush(louis);
 
 	platform_do_lowpower(cpu, &spurious);