1 files changed, 52 insertions, 0 deletions
diff --git a/src/include/cpu/x86/msr.h b/src/include/cpu/x86/msr.h
new file mode 100644
index 0000000000..4f481bdf4b
--- /dev/null
+++ b/src/include/cpu/x86/msr.h
@@ -0,0 +1,52 @@
+#ifndef CPU_X86_MSR_H
+#define CPU_X86_MSR_H
+
+
+#ifdef __ROMCC__
+
+typedef __builtin_msr_t msr_t;
+
+static msr_t rdmsr(unsigned long index)
+{
+	return __builtin_rdmsr(index);
+}
+
+static void wrmsr(unsigned long index, msr_t msr)
+{
+	__builtin_wrmsr(index, msr.lo, msr.hi);
+}
+
+#endif /* __ROMCC__ */
+
+#if defined(__GNUC__) && !defined(__ROMCC__)
+
+typedef struct msr_struct 
+{
+	unsigned lo;
+	unsigned hi;
+} msr_t;
+
+static inline msr_t rdmsr(unsigned index)
+{
+	msr_t result;
+	__asm__ __volatile__ (
+		"rdmsr"
+		: "=a" (result.lo), "=d" (result.hi)
+		: "c" (index)
+		);
+	return result;
+}
+
+static inline void wrmsr(unsigned index, msr_t msr)
+{
+	__asm__ __volatile__ (
+		"wrmsr"
+		: /* No outputs */
+		: "c" (index), "a" (msr.lo), "d" (msr.hi)
+		);
+}
+
+#endif /* __GNUC__ */
+
+
+#endif /* CPU_X86_MSR_H */