From 80de049561f4d560c50341562b7e93ff45a1d8a0 Mon Sep 17 00:00:00 2001
From: Bin Meng <bmeng.cn@gmail.com>
Date: Sun, 9 Nov 2014 22:19:25 +0800
Subject: x86: Add quick TSC calibration via PIT

Use the same way that Linux does for quick TSC calibration via PIT
when calibration via MSR fails.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
---
 arch/x86/include/asm/i8254.h | 3 +++
 1 file changed, 3 insertions(+)

(limited to 'arch/x86/include/asm/i8254.h')

diff --git a/arch/x86/include/asm/i8254.h b/arch/x86/include/asm/i8254.h
index c3ccd4f..4116de1 100644
--- a/arch/x86/include/asm/i8254.h
+++ b/arch/x86/include/asm/i8254.h
@@ -36,4 +36,7 @@
 #define PIT_CMD_MODE4	0x08		/* Select mode 4 */
 #define PIT_CMD_MODE5	0x0A		/* Select mode 5 */
 
+/* The clock frequency of the i8253/i8254 PIT */
+#define PIT_TICK_RATE	1193182ul
+
 #endif
-- 
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