powerpc/pasemi: Use raw spinlock in SMP TB sync

spin_lock() can hang if called while the timebase is frozen, so use a raw lock instead, also disable interrupts while at it. Signed-off-by: Benjamin Herrenschmidt <[email protected]>
RyanHsu · Jun 26, 2009 · 6893ce6 · 6893ce6
1 parent c4007a2
commit 6893ce6
Showing 1 changed file with 10 additions and 5 deletions.
diff --git a/arch/powerpc/platforms/pasemi/setup.c b/arch/powerpc/platforms/pasemi/setup.c
@@ -71,31 +71,36 @@ static void pas_restart(char *cmd)
 }
 
 #ifdef CONFIG_SMP
-static DEFINE_SPINLOCK(timebase_lock);
+static raw_spinlock_t timebase_lock;
 static unsigned long timebase;
 
 static void __devinit pas_give_timebase(void)
 {
-	spin_lock(&timebase_lock);
+	unsigned long flags;
+
+	local_irq_save(flags);
+	hard_irq_disable();
+	__raw_spin_lock(&timebase_lock);
 	mtspr(SPRN_TBCTL, TBCTL_FREEZE);
 	isync();
 	timebase = get_tb();
-	spin_unlock(&timebase_lock);
+	__raw_spin_unlock(&timebase_lock);
 
 	while (timebase)
 		barrier();
 	mtspr(SPRN_TBCTL, TBCTL_RESTART);
+	local_irq_restore(flags);
 }
 
 static void __devinit pas_take_timebase(void)
 {
 	while (!timebase)
 		smp_rmb();
 
-	spin_lock(&timebase_lock);
+	__raw_spin_lock(&timebase_lock);
 	set_tb(timebase >> 32, timebase & 0xffffffff);
 	timebase = 0;
-	spin_unlock(&timebase_lock);
+	__raw_spin_unlock(&timebase_lock);
 }
 
 struct smp_ops_t pas_smp_ops = {