diff --git a/configs/firefly-rk3288_defconfig b/configs/firefly-rk3288_defconfig
index b8eae0f..ba5b3ba 100644
--- a/configs/firefly-rk3288_defconfig
+++ b/configs/firefly-rk3288_defconfig
@@ -55,6 +55,7 @@
 CONFIG_MMC_DW=y
 CONFIG_MMC_DW_ROCKCHIP=y
 CONFIG_SPI_FLASH=y
+CONFIG_SF_DEFAULT_SPEED=20000000
 CONFIG_DM_ETH=y
 CONFIG_ETH_DESIGNWARE=y
 CONFIG_GMAC_ROCKCHIP=y