diff --git a/drivers/serial/serial_stm32.c b/drivers/serial/serial_stm32.c
index 23d476f..fb03954 100644
--- a/drivers/serial/serial_stm32.c
+++ b/drivers/serial/serial_stm32.c
@@ -30,7 +30,7 @@
  */
 #define ONE_BYTE_B115200_US		87
 
-static void _stm32_serial_setbrg(fdt_addr_t base,
+static void _stm32_serial_setbrg(void __iomem *base,
 				 struct stm32_uart_info *uart_info,
 				 u32 clock_rate,
 				 int baudrate)
@@ -75,7 +75,7 @@
 	struct stm32x7_serial_plat *plat = dev_get_plat(dev);
 	bool stm32f4 = plat->uart_info->stm32f4;
 	u8 uart_enable_bit = plat->uart_info->uart_enable_bit;
-	u32 cr1 = plat->base + CR1_OFFSET(stm32f4);
+	void __iomem *cr1 = plat->base + CR1_OFFSET(stm32f4);
 	u32 config = 0;
 	uint parity = SERIAL_GET_PARITY(serial_config);
 	uint bits = SERIAL_GET_BITS(serial_config);
@@ -122,7 +122,7 @@
 {
 	struct stm32x7_serial_plat *plat = dev_get_plat(dev);
 	bool stm32f4 = plat->uart_info->stm32f4;
-	fdt_addr_t base = plat->base;
+	void __iomem *base = plat->base;
 	u32 isr = readl(base + ISR_OFFSET(stm32f4));
 
 	if ((isr & USART_ISR_RXNE) == 0)
@@ -141,7 +141,7 @@
 	return readl(base + RDR_OFFSET(stm32f4));
 }
 
-static int _stm32_serial_putc(fdt_addr_t base,
+static int _stm32_serial_putc(void __iomem *base,
 			      struct stm32_uart_info *uart_info,
 			      const char c)
 {
@@ -166,7 +166,7 @@
 {
 	struct stm32x7_serial_plat *plat = dev_get_plat(dev);
 	bool stm32f4 = plat->uart_info->stm32f4;
-	fdt_addr_t base = plat->base;
+	void __iomem *base = plat->base;
 
 	if (input)
 		return readl(base + ISR_OFFSET(stm32f4)) &
@@ -176,7 +176,7 @@
 			USART_ISR_TXE ? 0 : 1;
 }
 
-static void _stm32_serial_init(fdt_addr_t base,
+static void _stm32_serial_init(void __iomem *base,
 			       struct stm32_uart_info *uart_info)
 {
 	bool stm32f4 = uart_info->stm32f4;
@@ -250,11 +250,14 @@
 static int stm32_serial_of_to_plat(struct udevice *dev)
 {
 	struct stm32x7_serial_plat *plat = dev_get_plat(dev);
+	fdt_addr_t addr;
 
-	plat->base = dev_read_addr(dev);
-	if (plat->base == FDT_ADDR_T_NONE)
+	addr = dev_read_addr(dev);
+	if (addr == FDT_ADDR_T_NONE)
 		return -EINVAL;
 
+	plat->base = (void __iomem *)addr;
+
 	return 0;
 }
 
@@ -297,7 +300,7 @@
 
 static inline void _debug_uart_init(void)
 {
-	fdt_addr_t base = CONFIG_VAL(DEBUG_UART_BASE);
+	void __iomem *base = (void __iomem *)CONFIG_VAL(DEBUG_UART_BASE);
 	struct stm32_uart_info *uart_info = _debug_uart_info();
 
 	_stm32_serial_init(base, uart_info);
@@ -308,7 +311,7 @@
 
 static inline void _debug_uart_putc(int c)
 {
-	fdt_addr_t base = CONFIG_VAL(DEBUG_UART_BASE);
+	void __iomem *base = (void __iomem *)CONFIG_VAL(DEBUG_UART_BASE);
 	struct stm32_uart_info *uart_info = _debug_uart_info();
 
 	while (_stm32_serial_putc(base, uart_info, c) == -EAGAIN)