diff --git a/build/boards/cv180x/cv1800b_milkv_duo_sd/u-boot/cvi_board_init.c b/build/boards/cv180x/cv1800b_milkv_duo_sd/u-boot/cvi_board_init.c
index 77235e0a9..c860cf0a4 100644
--- a/build/boards/cv180x/cv1800b_milkv_duo_sd/u-boot/cvi_board_init.c
+++ b/build/boards/cv180x/cv1800b_milkv_duo_sd/u-boot/cvi_board_init.c
@@ -16,6 +16,10 @@ int cvi_board_init(void)
 	PINMUX_CONFIG(IIC0_SDA, XGPIOA_29);
 	PINMUX_CONFIG(IIC0_SCL, XGPIOA_28);
 
+	// PWM
+	PINMUX_CONFIG(SD1_D2, PWM_5);
+	PINMUX_CONFIG(SD1_D1, PWM_6);
+
 	// SPI
 	PINMUX_CONFIG(SD1_CLK, SPI2_SCK);
 	PINMUX_CONFIG(SD1_CMD, SPI2_SDO);