diff options
| author | Masahiro Yamada <yamada.masahiro@socionext.com> | 2020-07-10 01:12:07 +0900 |
|---|---|---|
| committer | Masahiro Yamada <yamada.masahiro@socionext.com> | 2020-07-11 21:30:21 +0900 |
| commit | 26f7a7deab33e9fb46abec50a5209878fc3b53dc (patch) | |
| tree | 9f5d4c37130966a32a703156368c44720bc2e7c5 | |
| parent | 70434ab9de795b205608067d9a5e067f30ad3629 (diff) | |
| download | u-boot-26f7a7deab33e9fb46abec50a5209878fc3b53dc.tar.gz | |
serial: uniphier: flush transmitter before changing hardware settings
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>
| -rw-r--r-- | drivers/serial/serial_uniphier.c | 8 |
1 files changed, 8 insertions, 0 deletions
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); |