From 9f7295672fd1b66f1ee39dbf8e797ce78b6ee2ab Mon Sep 17 00:00:00 2001
From: Steffen Vogel <steffen.vogel@rwth-aachen.de>
Date: Wed, 23 Apr 2014 18:36:23 +0200
Subject: [PATCH] fixed rdtsc on x86_64 (upper 32bits were missing)

---
 arch/x86/include/asm/processor.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 56d9461b..817aef44 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -228,9 +228,15 @@ inline static uint32_t has_nx(void)
  */
 inline static uint64_t rdtsc(void)
 {
+#ifdef CONFIG_X86_32
 	uint64_t x;
 	asm volatile ("rdtsc" : "=A" (x));
 	return x;
+#elif defined(CONFIG_X86_64)
+	uint64_t lo, hi;
+	asm volatile ("rdtsc" : "=a"(lo), "=d"(hi) );
+	return (hi << 32 | lo);
+#endif
 }
 
 /** @brief Flush cache