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

[Shawn Guo]

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 
> Signed-off-by: Stefan Agner 

Applied, thanks.

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

[Stefan Agner]

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 
Signed-off-by: Stefan Agner 
---
 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 
 #include 
+#include 
 #include 
 #include 
 
 #include "common.h"
 
-static inline void cpu_enter_lowpower(void)
-{
-   unsigned int v;
-
-   asm volatile(
-   "mcrp15, 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