diff --git a/wolfcrypt/src/integer.c b/wolfcrypt/src/integer.c
index 2551ca103..cfe9d27a8 100644
--- a/wolfcrypt/src/integer.c
+++ b/wolfcrypt/src/integer.c
@@ -4443,11 +4443,20 @@ static int mp_prime_miller_rabin (mp_int * a, mp_int * b, int *result)
     goto LBL_R;
   }
 #if defined(WOLFSSL_HAVE_SP_RSA) || defined(WOLFSSL_HAVE_SP_DH)
+#ifndef WOLFSSL_SP_NO_2048
   if (mp_count_bits(a) == 1024)
       err = sp_ModExp_1024(b, &r, a, &y);
   else if (mp_count_bits(a) == 2048)
       err = sp_ModExp_2048(b, &r, a, &y);
   else
+#endif
+#ifndef WOLFSSL_SP_NO_3072
+  if (mp_count_bits(a) == 1536)
+      err = sp_ModExp_1536(b, &r, a, &y);
+  else if (mp_count_bits(a) == 3072)
+      err = sp_ModExp_3072(b, &r, a, &y);
+  else
+#endif
 #endif
       err = mp_exptmod (b, &r, a, &y);
   if (err != MP_OKAY)
diff --git a/wolfcrypt/src/tfm.c b/wolfcrypt/src/tfm.c
index f30a752a5..b7cb3d69a 100644
--- a/wolfcrypt/src/tfm.c
+++ b/wolfcrypt/src/tfm.c
@@ -3553,11 +3553,20 @@ static int fp_prime_miller_rabin_ex(fp_int * a, fp_int * b, int *result,
   fp_zero(y);
 #if (defined(WOLFSSL_HAVE_SP_RSA) && !defined(WOLFSSL_RSA_PUBLIC_ONLY)) || \
                                                      defined(WOLFSSL_HAVE_SP_DH)
+#ifndef WOLFSSL_SP_NO_2048
   if (fp_count_bits(a) == 1024)
       sp_ModExp_1024(b, r, a, y);
   else if (fp_count_bits(a) == 2048)
       sp_ModExp_2048(b, r, a, y);
   else
+#endif
+#ifndef WOLFSSL_SP_NO_3072
+  if (fp_count_bits(a) == 1536)
+      sp_ModExp_1536(b, r, a, y);
+  else if (fp_count_bits(a) == 3072)
+      sp_ModExp_3072(b, r, a, y);
+  else
+#endif
 #endif
       fp_exptmod(b, r, a, y);
 
diff --git a/wolfssl/openssl/bn.h b/wolfssl/openssl/bn.h
index e3311b395..c5176813b 100644
--- a/wolfssl/openssl/bn.h
+++ b/wolfssl/openssl/bn.h
@@ -40,7 +40,9 @@
 typedef struct WOLFSSL_BIGNUM {
     int neg;        /* openssh deference */
     void *internal; /* our big num */
-#if defined(USE_FAST_MATH) && !defined(HAVE_WOLF_BIGINT)
+#ifdef WOLFSSL_SP_MATH
+    sp_int fp;
+#elif defined(USE_FAST_MATH) && !defined(HAVE_WOLF_BIGINT)
     fp_int fp;
 #endif
 } WOLFSSL_BIGNUM;