diff --git a/common/build.mk b/common/build.mk
index c3a9023fcb..6c13a9c4d0 100644
--- a/common/build.mk
+++ b/common/build.mk
@@ -127,3 +127,8 @@ else
 common-y+=test_util.o
 endif
 common-$(TEST_BUILD)+=sensor_common.o
+
+ifneq ($(CONFIG_RSA_OPTIMIZED),)
+$(out)/RW/common/rsa.o: CFLAGS+=-O3
+$(out)/RO/common/rsa.o: CFLAGS+=-O3
+endif
diff --git a/include/config.h b/include/config.h
index 94ddba963c..19a6653161 100644
--- a/include/config.h
+++ b/include/config.h
@@ -1782,6 +1782,12 @@
 /* Use RSA exponent 3 instead of F4 (65537) */
 #undef CONFIG_RSA_EXPONENT_3
 
+/*
+ * Adjust the compiler optimization flags for the RSA code to get a speed-up
+ * at the expense of a small code size delta.
+ */
+#undef CONFIG_RSA_OPTIMIZED
+
 /*
  * Verify the RW firmware using the RSA signature.
  * (for accessories without software sync)