summaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-imx/hotplug.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/mach-imx/hotplug.c')
-rw-r--r--arch/arm/mach-imx/hotplug.c42
1 files changed, 41 insertions, 1 deletions
diff --git a/arch/arm/mach-imx/hotplug.c b/arch/arm/mach-imx/hotplug.c
index 89493ab..20ed2d5 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 +20,44 @@ 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");
+}
+
+static inline void cpu_leave_lowpower(void)
+{
+ unsigned int v;
+
+ asm volatile(
+ "mrc p15, 0, %0, c1, c0, 0\n"
+ " orr %0, %0, %1\n"
+ " mcr p15, 0, %0, c1, c0, 0\n"
+ " mrc p15, 0, %0, c1, c0, 1\n"
+ " orr %0, %0, %2\n"
+ " mcr p15, 0, %0, c1, c0, 1\n"
+ : "=&r" (v)
+ : "Ir" (CR_C), "Ir" (0x40)
+ : "cc");
+}
+
/*
* platform-specific code to shutdown a CPU
*
@@ -26,9 +65,10 @@ 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();
+ cpu_leave_lowpower();
/* We should never return from idle */
panic("cpu %d unexpectedly exit from shutdown\n", cpu);