Thread (6 messages) 6 messages, 4 authors, 2014-05-27
STALE4417d

[PATCH] ARM: EXYNOS: Use wfi macro in platform_do_lowpower

From: Daniel Lezcano <hidden>
Date: 2014-05-22 11:53:20
Also in: linux-pm, linux-samsung-soc

On 05/22/2014 09:57 AM, Leela Krishna Amudala wrote:
This patch is originally based on commit b3377d186572 ("ARM: 7064/1:
vexpress: Use wfi macro in platform_do_lowpower.")

Current Exynos CPU hotplug code includes a hardcoded WFI
instruction, in ARM encoding.  When the kernel is compiled in Thumb-2
mode, this is invalid and causes the machine to hang hard when a CPU
is offlined.

Use wfi macro instead of the hardcoded WFI instruction.
Is it possible to change it for cpu_do_idle() ?

I guess, that should be backported to the previous kernel version, right 
? (Cc stable@).

Thanks
   -- Daniel
quoted hunk ↗ jump to hunk
Signed-off-by: Leela Krishna Amudala <redacted>
---
  arch/arm/mach-exynos/hotplug.c |    8 +-------
  1 file changed, 1 insertion(+), 7 deletions(-)
diff --git a/arch/arm/mach-exynos/hotplug.c b/arch/arm/mach-exynos/hotplug.c
index 69fa483..8a134d0 100644
--- a/arch/arm/mach-exynos/hotplug.c
+++ b/arch/arm/mach-exynos/hotplug.c
@@ -46,13 +46,7 @@ static inline void platform_do_lowpower(unsigned int cpu, int *spurious)
  		if (cpu == 1)
  			exynos_cpu_power_down(cpu);

-		/*
-		 * here's the WFI
-		 */
-		asm(".word	0xe320f003\n"
-		    :
-		    :
-		    : "memory", "cc");
+		wfi();

  		if (pen_release == cpu_logical_map(cpu)) {
  			/*

-- 
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