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Diffstat (limited to 'arch/arm/mach-imx/hotplug.c')
-rw-r--r--arch/arm/mach-imx/hotplug.c31
1 files changed, 27 insertions, 4 deletions
diff --git a/arch/arm/mach-imx/hotplug.c b/arch/arm/mach-imx/hotplug.c
index 89493abd497c..f8f7437c83b8 100644
--- a/arch/arm/mach-imx/hotplug.c
+++ b/arch/arm/mach-imx/hotplug.c
@@ -12,6 +12,7 @@
#include <linux/errno.h>
#include <asm/cacheflush.h>
+#include <asm/cp15.h>
#include <mach/common.h>
int platform_cpu_kill(unsigned int cpu)
@@ -19,6 +20,28 @@ int platform_cpu_kill(unsigned int cpu)
return 1;
}
+static inline void cpu_enter_lowpower(void)
+{
+ unsigned int v;
+
+ flush_cache_all();
+ 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
*
@@ -26,12 +49,12 @@ int platform_cpu_kill(unsigned int cpu)
*/
void platform_cpu_die(unsigned int cpu)
{
- flush_cache_all();
+ cpu_enter_lowpower();
imx_enable_cpu(cpu, false);
- cpu_do_idle();
- /* We should never return from idle */
- panic("cpu %d unexpectedly exit from shutdown\n", cpu);
+ /* spin here until hardware takes it down */
+ while (1)
+ ;
}
int platform_cpu_disable(unsigned int cpu)