Ensure the transmitter is empty when chaining the baudrate or any hardware settings. If a character is remaining in the transmitter, the console will be garbled.
Signed-off-by: Masahiro Yamada yamada.masahiro@socionext.com ---
drivers/serial/serial_uniphier.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/drivers/serial/serial_uniphier.c b/drivers/serial/serial_uniphier.c index 2ffab004bd..aaf8657ee1 100644 --- a/drivers/serial/serial_uniphier.c +++ b/drivers/serial/serial_uniphier.c @@ -43,6 +43,10 @@ static int uniphier_serial_setbrg(struct udevice *dev, int baudrate)
divisor = DIV_ROUND_CLOSEST(priv->uartclk, mode_x_div * baudrate);
+ /* flush the trasmitter before changing hw setting */ + while (!(readl(priv->membase + UNIPHIER_UART_LSR) & UART_LSR_TEMT)) + ; + writel(divisor, priv->membase + UNIPHIER_UART_DLR);
return 0; @@ -132,6 +136,10 @@ static int uniphier_serial_probe(struct udevice *dev)
priv->uartclk = clk_data->clk_rate;
+ /* flush the trasmitter empty before changing hw setting */ + while (!(readl(priv->membase + UNIPHIER_UART_LSR) & UART_LSR_TEMT)) + ; + tmp = readl(priv->membase + UNIPHIER_UART_LCR_MCR); tmp &= ~UNIPHIER_UART_LCR_MASK; tmp |= FIELD_PREP(UNIPHIER_UART_LCR_MASK, UART_LCR_WLEN8);