1 files changed, 42 insertions, 3 deletions

diff --git a/arch/arm/mach-exynos/hotplug.c b/arch/arm/mach-exynos/hotplug.c
index f4d7dd20cdac..c3f825b27947 100644
--- a/arch/arm/mach-exynos/hotplug.c
+++ b/arch/arm/mach-exynos/hotplug.c
@@ -20,10 +20,11 @@
 #include <asm/smp_plat.h>
 
 #include <mach/regs-pmu.h>
+#include <plat/cpu.h>
 
 #include "common.h"
 
-static inline void cpu_enter_lowpower(void)
+static inline void cpu_enter_lowpower_a9(void)
 {
         unsigned int v;
 
@@ -45,6 +46,35 @@ static inline void cpu_enter_lowpower(void)
           : "cc");
 }
 
+static inline void cpu_enter_lowpower_a15(void)
+{
+        unsigned int v;
+
+        asm volatile(
+        "       mrc     p15, 0, %0, c1, c0, 0\n"
+        "       bic     %0, %0, %1\n"
+        "       mcr     p15, 0, %0, c1, c0, 0\n"
+          : "=&r" (v)
+          : "Ir" (CR_C)
+          : "cc");
+
+        flush_cache_louis();
+
+        asm volatile(
+        /*
+        * Turn off coherency
+        */
+        "       mrc     p15, 0, %0, c1, c0, 1\n"
+        "       bic     %0, %0, %1\n"
+        "       mcr     p15, 0, %0, c1, c0, 1\n"
+        : "=&r" (v)
+        : "Ir" (0x40)
+        : "cc");
+
+        isb();
+        dsb();
+}
+
 static inline void cpu_leave_lowpower(void)
 {
         unsigned int v;
@@ -103,11 +133,20 @@ static inline void platform_do_lowpower(unsigned int cpu, int *spurious)
 void __ref exynos_cpu_die(unsigned int cpu)
 {
         int spurious = 0;
+        int primary_part = 0;
 
         /*
-         * we're ready for shutdown now, so do it
+         * we're ready for shutdown now, so do it.
+         * Exynos4 is A9 based while Exynos5 is A15; check the CPU part
+         * number by reading the Main ID register and then perform the
+         * appropriate sequence for entering low power.
          */
-        cpu_enter_lowpower();
+        asm("mrc p15, 0, %0, c0, c0, 0" : "=r"(primary_part) : : "cc");
+        if ((primary_part & 0xfff0) == 0xc0f0)
+                cpu_enter_lowpower_a15();
+        else
+                cpu_enter_lowpower_a9();
+
         platform_do_lowpower(cpu, &spurious);
 
         /*