X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;ds=sidebyside;f=drivers%2Fserial%2Fserial_stm32x7.c;h=61e8167a3bc9e1d4df566aaccc61c27de6dacb4c;hb=e2351d5cf1e97408b4c52bafeaa85e0ca85c920c;hp=bdabf87e50eee856bb184f718e7c37b638acaa42;hpb=a821c4af79e4f5ce9b629b20473863397bbe9b10;p=oweals%2Fu-boot.git

diff --git a/drivers/serial/serial_stm32x7.c b/drivers/serial/serial_stm32x7.c
index bdabf87e50..61e8167a3b 100644
--- a/drivers/serial/serial_stm32x7.c
+++ b/drivers/serial/serial_stm32x7.c
@@ -20,7 +20,7 @@ static int stm32_serial_setbrg(struct udevice *dev, int baudrate)
 {
 	struct stm32x7_serial_platdata *plat = dev->platdata;
 	struct stm32_usart *const usart = plat->base;
-	u32  clock, int_div, frac_div, tmp;
+	u32  clock, int_div, mantissa, fraction, oversampling;
 
 	if (((u32)usart & STM32_BUS_MASK) == APB1_PERIPH_BASE)
 		clock = clock_get(CLOCK_APB1);
@@ -29,11 +29,20 @@ static int stm32_serial_setbrg(struct udevice *dev, int baudrate)
 	else
 		return -EINVAL;
 
-	int_div = (25 * clock) / (4 * baudrate);
-	tmp = ((int_div / 100) << USART_BRR_M_SHIFT) & USART_BRR_M_MASK;
-	frac_div = int_div - (100 * (tmp >> USART_BRR_M_SHIFT));
-	tmp |= (((frac_div * 16) + 50) / 100) & USART_BRR_F_MASK;
-	writel(tmp, &usart->brr);
+	int_div = DIV_ROUND_CLOSEST(clock, baudrate);
+
+	if (int_div < 16) {
+		oversampling = 8;
+		setbits_le32(&usart->cr1, USART_CR1_OVER8);
+	} else {
+		oversampling = 16;
+		clrbits_le32(&usart->cr1, USART_CR1_OVER8);
+	}
+
+	mantissa = (int_div / oversampling) << USART_BRR_M_SHIFT;
+	fraction = int_div % oversampling;
+
+	writel(mantissa | fraction, &usart->brr);
 
 	return 0;
 }
@@ -93,6 +102,9 @@ static int stm32_serial_probe(struct udevice *dev)
 	}
 #endif
 
+	/* Disable usart-> disable overrun-> enable usart */
+	clrbits_le32(&usart->cr1, USART_CR1_RE | USART_CR1_TE | USART_CR1_UE);
+	setbits_le32(&usart->cr3, USART_CR3_OVRDIS);
 	setbits_le32(&usart->cr1, USART_CR1_RE | USART_CR1_TE | USART_CR1_UE);
 
 	return 0;
@@ -100,8 +112,8 @@ static int stm32_serial_probe(struct udevice *dev)
 
 #if CONFIG_IS_ENABLED(OF_CONTROL)
 static const struct udevice_id stm32_serial_id[] = {
-	{.compatible = "st,stm32-usart"},
-	{.compatible = "st,stm32-uart"},
+	{.compatible = "st,stm32f7-usart"},
+	{.compatible = "st,stm32f7-uart"},
 	{}
 };