diff --git a/drivers/serial/serial_mtk.c b/drivers/serial/serial_mtk.c
index 22251c5..03b9e86 100644
--- a/drivers/serial/serial_mtk.c
+++ b/drivers/serial/serial_mtk.c
@@ -10,6 +10,7 @@
 #include <common.h>
 #include <div64.h>
 #include <dm.h>
+#include <dm/device_compat.h>
 #include <errno.h>
 #include <log.h>
 #include <serial.h>
@@ -70,27 +71,37 @@
 #define BAUD_ALLOW_MAX(baud)	((baud) + (baud) * 3 / 100)
 #define BAUD_ALLOW_MIX(baud)	((baud) - (baud) * 3 / 100)
 
+/* struct mtk_serial_priv -	Structure holding all information used by the
+ *				driver
+ * @regs:			Register base of the serial port
+ * @clk:			The baud clock device
+ * @fixed_clk_rate:		Fallback fixed baud clock rate if baud clock
+ *				device is not specified
+ * @force_highspeed:		Force using high-speed mode
+ */
 struct mtk_serial_priv {
 	struct mtk_serial_regs __iomem *regs;
-	u32 clock;
+	struct clk clk;
+	u32 fixed_clk_rate;
 	bool force_highspeed;
 };
 
-static void _mtk_serial_setbrg(struct mtk_serial_priv *priv, int baud)
+static void _mtk_serial_setbrg(struct mtk_serial_priv *priv, int baud,
+			       uint clk_rate)
 {
 	u32 quot, realbaud, samplecount = 1;
 
 	/* Special case for low baud clock */
-	if (baud <= 115200 && priv->clock <= 12000000) {
+	if (baud <= 115200 && clk_rate == 12000000) {
 		writel(3, &priv->regs->highspeed);
 
-		quot = DIV_ROUND_CLOSEST(priv->clock, 256 * baud);
+		quot = DIV_ROUND_CLOSEST(clk_rate, 256 * baud);
 		if (quot == 0)
 			quot = 1;
 
-		samplecount = DIV_ROUND_CLOSEST(priv->clock, quot * baud);
+		samplecount = DIV_ROUND_CLOSEST(clk_rate, quot * baud);
 
-		realbaud = priv->clock / samplecount / quot;
+		realbaud = clk_rate / samplecount / quot;
 		if (realbaud > BAUD_ALLOW_MAX(baud) ||
 		    realbaud < BAUD_ALLOW_MIX(baud)) {
 			pr_info("baud %d can't be handled\n", baud);
@@ -104,7 +115,7 @@
 
 	if (baud <= 115200) {
 		writel(0, &priv->regs->highspeed);
-		quot = DIV_ROUND_CLOSEST(priv->clock, 16 * baud);
+		quot = DIV_ROUND_CLOSEST(clk_rate, 16 * baud);
 	} else if (baud <= 576000) {
 		writel(2, &priv->regs->highspeed);
 
@@ -112,13 +123,13 @@
 		if ((baud == 500000) || (baud == 576000))
 			baud = 460800;
 
-		quot = DIV_ROUND_UP(priv->clock, 4 * baud);
+		quot = DIV_ROUND_UP(clk_rate, 4 * baud);
 	} else {
 use_hs3:
 		writel(3, &priv->regs->highspeed);
 
-		quot = DIV_ROUND_UP(priv->clock, 256 * baud);
-		samplecount = DIV_ROUND_CLOSEST(priv->clock, quot * baud);
+		quot = DIV_ROUND_UP(clk_rate, 256 * baud);
+		samplecount = DIV_ROUND_CLOSEST(clk_rate, quot * baud);
 	}
 
 set_baud:
@@ -167,8 +178,13 @@
 static int mtk_serial_setbrg(struct udevice *dev, int baudrate)
 {
 	struct mtk_serial_priv *priv = dev_get_priv(dev);
+	u32 clk_rate;
 
-	_mtk_serial_setbrg(priv, baudrate);
+	clk_rate = clk_get_rate(&priv->clk);
+	if (IS_ERR_VALUE(clk_rate) || clk_rate == 0)
+		clk_rate = priv->fixed_clk_rate;
+
+	_mtk_serial_setbrg(priv, baudrate, clk_rate);
 
 	return 0;
 }
@@ -211,7 +227,6 @@
 {
 	struct mtk_serial_priv *priv = dev_get_priv(dev);
 	fdt_addr_t addr;
-	struct clk clk;
 	int err;
 
 	addr = dev_read_addr(dev);
@@ -220,22 +235,19 @@
 
 	priv->regs = map_physmem(addr, 0, MAP_NOCACHE);
 
-	err = clk_get_by_index(dev, 0, &clk);
-	if (!err) {
-		err = clk_get_rate(&clk);
-		if (!IS_ERR_VALUE(err))
-			priv->clock = err;
-	} else if (err != -ENOENT && err != -ENODEV && err != -ENOSYS) {
-		debug("mtk_serial: failed to get clock\n");
-		return err;
-	}
-
-	if (!priv->clock)
-		priv->clock = dev_read_u32_default(dev, "clock-frequency", 0);
-
-	if (!priv->clock) {
-		debug("mtk_serial: clock not defined\n");
-		return -EINVAL;
+	err = clk_get_by_index(dev, 0, &priv->clk);
+	if (err) {
+		err = dev_read_u32(dev, "clock-frequency", &priv->fixed_clk_rate);
+		if (err) {
+			dev_err(dev, "baud clock not defined\n");
+			return -EINVAL;
+		}
+	} else {
+		err = clk_get_rate(&priv->clk);
+		if (IS_ERR_VALUE(err)) {
+			dev_err(dev, "invalid baud clock\n");
+			return -EINVAL;
+		}
 	}
 
 	priv->force_highspeed = dev_read_bool(dev, "mediatek,force-highspeed");
@@ -273,7 +285,7 @@
 #define DECLARE_HSUART_PRIV(port) \
 	static struct mtk_serial_priv mtk_hsuart##port = { \
 	.regs = (struct mtk_serial_regs *)CONFIG_SYS_NS16550_COM##port, \
-	.clock = CONFIG_SYS_NS16550_CLK \
+	.fixed_clk_rate = CONFIG_SYS_NS16550_CLK \
 };
 
 #define DECLARE_HSUART_FUNCTIONS(port) \
@@ -282,12 +294,14 @@
 		writel(0, &mtk_hsuart##port.regs->ier); \
 		writel(UART_MCRVAL, &mtk_hsuart##port.regs->mcr); \
 		writel(UART_FCRVAL, &mtk_hsuart##port.regs->fcr); \
-		_mtk_serial_setbrg(&mtk_hsuart##port, gd->baudrate); \
+		_mtk_serial_setbrg(&mtk_hsuart##port, gd->baudrate, \
+				   mtk_hsuart##port.fixed_clk_rate); \
 		return 0 ; \
 	} \
 	static void mtk_serial##port##_setbrg(void) \
 	{ \
-		_mtk_serial_setbrg(&mtk_hsuart##port, gd->baudrate); \
+		_mtk_serial_setbrg(&mtk_hsuart##port, gd->baudrate, \
+				   mtk_hsuart##port.fixed_clk_rate); \
 	} \
 	static int mtk_serial##port##_getc(void) \
 	{ \
@@ -427,13 +441,13 @@
 	struct mtk_serial_priv priv;
 
 	priv.regs = (void *) CONFIG_VAL(DEBUG_UART_BASE);
-	priv.clock = CONFIG_DEBUG_UART_CLOCK;
+	priv.fixed_clk_rate = CONFIG_DEBUG_UART_CLOCK;
 
 	writel(0, &priv.regs->ier);
 	writel(UART_MCRVAL, &priv.regs->mcr);
 	writel(UART_FCRVAL, &priv.regs->fcr);
 
-	_mtk_serial_setbrg(&priv, CONFIG_BAUDRATE);
+	_mtk_serial_setbrg(&priv, CONFIG_BAUDRATE, priv.fixed_clk_rate);
 }
 
 static inline void _debug_uart_putc(int ch)