diff --git a/arch/x86_64/include/intel64/arch.h b/arch/x86_64/include/intel64/arch.h
index c3511cb4931..1d0cff6057a 100644
--- a/arch/x86_64/include/intel64/arch.h
+++ b/arch/x86_64/include/intel64/arch.h
@@ -208,6 +208,8 @@
 #  define X86_64_CPUID_07_AVX512VL    (1 << 31)
 #define X86_64_CPUID_XSAVE            0x0d
 #define X86_64_CPUID_TSC              0x15
+#define X86_64_CPUID_EXTINFO          0x80000001
+#  define X86_64_CPUID_EXTINFO_RDTSCP (1 << 27)
 
 /* MSR Definitions */