diff --git a/src/southbridge/nvidia/ck804/ck804.h b/src/southbridge/nvidia/ck804/ck804.h
index 3da18f475a..e6641ea86d 100644
--- a/src/southbridge/nvidia/ck804/ck804.h
+++ b/src/southbridge/nvidia/ck804/ck804.h
@@ -35,4 +35,8 @@
 #define CK804B_SYSCTRL_IO_BASE (SYSCTRL_IO_BASE + 0x8000)
 #endif
 
+#ifdef __PRE_RAM__
+void enable_fid_change_on_sb(unsigned sbbusn, unsigned sbdn);
+#endif
+
 #endif
diff --git a/src/southbridge/nvidia/ck804/early_setup_car.c b/src/southbridge/nvidia/ck804/early_setup_car.c
index d8121462b5..32943db3d5 100644
--- a/src/southbridge/nvidia/ck804/early_setup_car.c
+++ b/src/southbridge/nvidia/ck804/early_setup_car.c
@@ -378,3 +378,9 @@ void soft_reset(void)
 	outb(0x02, 0x0cf9);
 	outb(0x06, 0x0cf9);
 }
+
+void enable_fid_change_on_sb(unsigned sbbusn, unsigned sbdn)
+{
+        /* The default value for CK804 is good. */
+        /* Set VFSMAF (VID/FID System Management Action Field) to 2. */
+}
\ No newline at end of file