2019-04-10 23:15:53

by Stefan Agner

Subject: [PATCH] ARM: imx: use generic function to exit coherency

The common ARM architecture code provides a generic function to exit
coherency called v7_exit_coherency_flush(). Replace the machine
specific implementation using the generic function.

Tested on a i.MX 6Dual by hotplugging the secondary CPU under load
through sysfs several 1000 times.

Tested-by: Stefan Agner <[email protected]>
Signed-off-by: Stefan Agner <[email protected]>
---
arch/arm/mach-imx/hotplug.c | 24 ++----------------------
1 file changed, 2 insertions(+), 22 deletions(-)

diff --git a/arch/arm/mach-imx/hotplug.c b/arch/arm/mach-imx/hotplug.c
index b35e99cc5e5b..7a74a9b89a49 100644
--- a/arch/arm/mach-imx/hotplug.c
+++ b/arch/arm/mach-imx/hotplug.c
@@ -12,32 +12,12 @@

#include <linux/errno.h>
#include <linux/jiffies.h>
+#include <asm/cacheflush.h>
#include <asm/cp15.h>
#include <asm/proc-fns.h>

#include "common.h"

-static inline void cpu_enter_lowpower(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");
-}
-
/*
* platform-specific code to shutdown a CPU
*
@@ -45,7 +25,7 @@ static inline void cpu_enter_lowpower(void)
*/
void imx_cpu_die(unsigned int cpu)
{
- cpu_enter_lowpower();
+ v7_exit_coherency_flush(louis);
/*
* We use the cpu jumping argument register to sync with
* imx_cpu_kill() which is running on cpu0 and waiting for
--
2.21.0

2019-04-16 05:48:05

by Shawn Guo

Subject: Re: [PATCH] ARM: imx: use generic function to exit coherency

On Thu, Apr 11, 2019 at 01:14:12AM +0200, Stefan Agner wrote:
> The common ARM architecture code provides a generic function to exit
> coherency called v7_exit_coherency_flush(). Replace the machine
> specific implementation using the generic function.
>
> Tested on a i.MX 6Dual by hotplugging the secondary CPU under load
> through sysfs several 1000 times.
>
> Tested-by: Stefan Agner <[email protected]>
> Signed-off-by: Stefan Agner <[email protected]>

Applied, thanks.

2019-11-01 21:44:55

by Stefan Agner

Subject: Re: [PATCH] ARM: imx: use generic function to exit coherency

Hi Shawn,

On 2019-04-16 07:46, Shawn Guo wrote:
> On Thu, Apr 11, 2019 at 01:14:12AM +0200, Stefan Agner wrote:
>> The common ARM architecture code provides a generic function to exit
>> coherency called v7_exit_coherency_flush(). Replace the machine
>> specific implementation using the generic function.
>>
>> Tested on a i.MX 6Dual by hotplugging the secondary CPU under load
>> through sysfs several 1000 times.
>>
>> Tested-by: Stefan Agner <[email protected]>
>> Signed-off-by: Stefan Agner <[email protected]>
>
> Applied, thanks.

It seems like this patch never made it upstream. Any specific reason?

--
Stefan

2019-11-04 00:48:05

by Shawn Guo

Subject: Re: [PATCH] ARM: imx: use generic function to exit coherency

On Fri, Nov 01, 2019 at 10:40:46PM +0100, Stefan Agner wrote:
> Hi Shawn,
>
> On 2019-04-16 07:46, Shawn Guo wrote:
> > On Thu, Apr 11, 2019 at 01:14:12AM +0200, Stefan Agner wrote:
> >> The common ARM architecture code provides a generic function to exit
> >> coherency called v7_exit_coherency_flush(). Replace the machine
> >> specific implementation using the generic function.
> >>
> >> Tested on a i.MX 6Dual by hotplugging the secondary CPU under load
> >> through sysfs several 1000 times.
> >>
> >> Tested-by: Stefan Agner <[email protected]>
> >> Signed-off-by: Stefan Agner <[email protected]>
> >
> > Applied, thanks.
>
> It seems like this patch never made it upstream. Any specific reason?

It got lost due to some accident on my side. I'm sorry for that. I
will send it for the coming merge window.

Shawn