Merge branch 'old_next' into next

[pandora-kernel.git] / arch / arm / kernel / smp_scu.c

diff --git a/arch/arm/kernel/smp_scu.c b/arch/arm/kernel/smp_scu.c
index 9ab4149..a1e757c 100644 (file)
--- a/arch/arm/kernel/smp_scu.c
+++ b/arch/arm/kernel/smp_scu.c
@@ -50,3 +50,26 @@ void __init scu_enable(void __iomem *scu_base)
         */
        flush_cache_all();
 }
+
+/*
+ * Set the executing CPUs power mode as defined.  This will be in
+ * preparation for it executing a WFI instruction.
+ *
+ * This function must be called with preemption disabled, and as it
+ * has the side effect of disabling coherency, caches must have been
+ * flushed.  Interrupts must also have been disabled.
+ */
+int scu_power_mode(void __iomem *scu_base, unsigned int mode)
+{
+       unsigned int val;
+       int cpu = smp_processor_id();
+
+       if (mode > 3 || mode == 1 || cpu > 3)
+               return -EINVAL;
+
+       val = __raw_readb(scu_base + SCU_CPU_STATUS + cpu) & ~0x03;
+       val |= mode;
+       __raw_writeb(val, scu_base + SCU_CPU_STATUS + cpu);
+
+       return 0;
+}