1 files changed, 22 insertions, 1 deletions
diff --git a/arch/ppc64/kernel/pmc.c b/arch/ppc64/kernel/pmc.c
index 67be773f9c0..63d9481c3ec 100644
--- a/arch/ppc64/kernel/pmc.c
+++ b/arch/ppc64/kernel/pmc.c
@@ -26,7 +26,7 @@ static void dummy_perf(struct pt_regs *regs)
 	mtspr(SPRN_MMCR0, mmcr0);
 }
 
-static spinlock_t pmc_owner_lock = SPIN_LOCK_UNLOCKED;
+static DEFINE_SPINLOCK(pmc_owner_lock);
 static void *pmc_owner_caller; /* mostly for debugging */
 perf_irq_t perf_irq = dummy_perf;
 
@@ -65,3 +65,24 @@ void release_pmc_hardware(void)
 	spin_unlock(&pmc_owner_lock);
 }
 EXPORT_SYMBOL_GPL(release_pmc_hardware);
+
+void power4_enable_pmcs(void)
+{
+	unsigned long hid0;
+
+	hid0 = mfspr(HID0);
+	hid0 |= 1UL << (63 - 20);
+
+	/* POWER4 requires the following sequence */
+	asm volatile(
+		"sync\n"
+		"mtspr     %1, %0\n"
+		"mfspr     %0, %1\n"
+		"mfspr     %0, %1\n"
+		"mfspr     %0, %1\n"
+		"mfspr     %0, %1\n"
+		"mfspr     %0, %1\n"
+		"mfspr     %0, %1\n"
+		"isync" : "=&r" (hid0) : "i" (HID0), "0" (hid0):
+		"memory");
+}