diff --git a/include/gcc/sparcv9/ck_pr.h b/include/gcc/sparcv9/ck_pr.h
index 397c81c..051ad6a 100644
--- a/include/gcc/sparcv9/ck_pr.h
+++ b/include/gcc/sparcv9/ck_pr.h
@@ -32,6 +32,7 @@
 #endif
 
 #include <ck_cc.h>
+#include <ck_md.h>
 
 /*
  * The following represent supported atomic operations.
@@ -50,9 +51,24 @@ ck_pr_stall(void)
 	return;
 }
 
-/*
- * We must assume RMO.
- */
+#ifndef CK_MD_RMO
+	/*
+	 * By default, we will assume TSO model is used on SPARCv9.
+	 */
+#define CK_PR_FENCE(T, I)                               \
+        CK_CC_INLINE static void                        \
+        ck_pr_fence_strict_##T(void)                    \
+        {                                               \
+                __asm__ __volatile__(I ::: "memory");   \
+        }                                               \
+        CK_CC_INLINE static void ck_pr_fence_##T(void)  \
+        {                                               \
+                __asm__ __volatile__("" ::: "memory");  \
+        }
+#else
+	/*
+	 * If RMO is forced, then do not assume TSO model.
+	 */
 #define CK_PR_FENCE(T, I)                               \
         CK_CC_INLINE static void                        \
         ck_pr_fence_strict_##T(void)                    \
@@ -63,6 +79,7 @@ ck_pr_stall(void)
         {                                               \
                 __asm__ __volatile__(I ::: "memory");   \
         }
+#endif /* CK_MD_RMO */
 
 CK_PR_FENCE(load_depends, "")
 CK_PR_FENCE(store, "membar #StoreStore")