diff --git a/common_power.h b/common_power.h
index e3a1a7aef..68087b071 100644
--- a/common_power.h
+++ b/common_power.h
@@ -241,7 +241,7 @@ static inline int blas_quickdivide(blasint x, blasint y){
 #define HAVE_PREFETCH
 #endif
 
-#if defined(POWER3) || defined(POWER6) || defined(PPCG4) || defined(CELL) || defined(POWER8)
+#if defined(POWER3) || defined(POWER6) || defined(PPCG4) || defined(CELL) || defined(POWER8) || ( defined(PPC970) && defined(OS_DARWIN) )
 #define DCBT_ARG	0
 #else
 #define DCBT_ARG	8
diff --git a/param.h b/param.h
index 3cc400b54..48b7ef383 100644
--- a/param.h
+++ b/param.h
@@ -1999,7 +1999,7 @@ USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #define ZGEMM_DEFAULT_UNROLL_M 2
 #define ZGEMM_DEFAULT_UNROLL_N 2
 
-#ifdef OS_LINUX
+#if defined(OS_LINUX) || defined(OS_DARWIN)
 #if L2_SIZE == 1024976
 #define SGEMM_DEFAULT_P 320
 #define DGEMM_DEFAULT_P 256