diff --git jitterentropy-base-user.h jitterentropy-base-user.h
--- jitterentropy-base-user.h
+++ jitterentropy-base-user.h
@@ -196,42 +196,14 @@ static inline void jent_get_nstime(uint64_t *out)
 	*out = *(uint64_t *)(clk + 1);
 }
 
-#elif defined(__powerpc)
-/*
- * Uncomment this for newer PPC CPUs
- * Newer PPC CPUs do not support mftbu/mftb
- * these instructions were obsoleted and replaced by
- * mfspr.  special processor registers 268 and 269 are the
- * ones we want.
- */
- /* #define POWER_PC_USE_NEW_INSTRUCTIONS */
-
-/* taken from http://www.ecrypt.eu.org/ebats/cpucycles.html */
+#elif defined(__powerpc__)
 
 static inline void jent_get_nstime(uint64_t *out)
 {
-	unsigned long high;
-	unsigned long low;
-	unsigned long newhigh;
-	uint64_t result;
-#ifdef POWER_PC_USE_NEW_INSTRUCTIONS /* Newer PPC CPUs do not support mftbu/mftb */
-	__asm__ __volatile__(
-		"Lcpucycles:mfspr %0, 269;mfspr %1, 268;mfspr %2, 269;cmpw %0,%2;bne Lcpucycles"
-		: "=r" (high), "=r" (low), "=r" (newhigh)
-		);
-#else
-	__asm__ __volatile__(
-		"Lcpucycles:mftbu %0;mftb %1;mftbu %2;cmpw %0,%2;bne Lcpucycles"
-		: "=r" (high), "=r" (low), "=r" (newhigh)
-		);
-#endif
-	result = high;
-	result <<= 32;
-	result |= low;
-	*out = result;
+	*out = (uint64_t)__builtin_ppc_get_timebase();
 }
 
-#else /* (__x86_64__) || (__i386__) || (__aarch64__) || (__s390x__) || (__powerpc) */
+#else /* (__x86_64__) || (__i386__) || (__aarch64__) || (__s390x__) || (__powerpc__) */
 
 static inline void jent_get_nstime(uint64_t *out)
 {