i386: prepare sharing the PIT code

PIT clock events work already and the PIT handling is the same for
i386 and x86_64. x86_64 does not support PIT as a clock source, so
disable the PIT clocksource for x86_64.

Use the i386 i8253.h include file for x86_64 as well to share the
exports and the PIT constants.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>

1 files changed, 22 insertions, 4 deletions

diff --git a/include/asm-x86/i8253.h b/include/asm-x86/i8253.h
index b2a4f995a33f..7eff6fd27474 100644
--- a/include/asm-x86/i8253.h
+++ b/include/asm-x86/i8253.h
@@ -1,5 +1,23 @@
-#ifdef CONFIG_X86_32
-# include "i8253_32.h"
-#else
-# include "i8253_64.h"
+#ifndef __ASM_I8253_H__
+#define __ASM_I8253_H__
+
+#ifdef CONFIG_X86_64
+# include <asm/8253pit.h>
 #endif
+
+/* i8253A PIT registers */
+#define PIT_MODE                0x43
+#define PIT_CH0                 0x40
+#define PIT_CH2                 0x42
+
+extern spinlock_t i8253_lock;
+
+#ifdef CONFIG_GENERIC_CLOCKEVENTS
+
+extern struct clock_event_device *global_clock_event;
+
+extern void setup_pit_timer(void);
+
+#endif
+
+#endif  /* __ASM_I8253_H__ */