x86: wrap MCA_bus test around an ifdef

Only test for MCA_bus if support for MCA is compiled in.
Also, for x86_64, write the code inside the conditional
for consistency with i386. It won't bite us, since it'll
probably never select CONFIG_MCA anyway.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 8 insertions, 0 deletions

diff --git a/arch/x86/kernel/time_64.c b/arch/x86/kernel/time_64.c
index 2be67c24909e..207a7a1d7ac5 100644
--- a/arch/x86/kernel/time_64.c
+++ b/arch/x86/kernel/time_64.c
@@ -16,6 +16,7 @@
 #include <linux/interrupt.h>
 #include <linux/module.h>
 #include <linux/time.h>
+#include <linux/mca.h>
 
 #include <asm/i8253.h>
 #include <asm/hpet.h>
@@ -54,6 +55,13 @@ irqreturn_t timer_interrupt(int irq, void *dev_id)
 
         global_clock_event->event_handler(global_clock_event);
 
+#ifdef CONFIG_MCA
+        if (MCA_bus) {
+                u8 irq_v = inb_p(0x61);       /* read the current state */
+                outb_p(irq_v|0x80, 0x61);     /* reset the IRQ */
+        }
+#endif
+
         return IRQ_HANDLED;
 }