[U-Boot] [PATCH v2 01/28] serial: serial_mtk: enable FIFO and disable flow control
Weijie Gao
weijie.gao at mediatek.com
Wed Sep 18 02:15:35 UTC 2019
This patch adds codes to enable FIFO and disable flow control taken from
ns16550 driver.
Signed-off-by: Weijie Gao <weijie.gao at mediatek.com>
---
drivers/serial/serial_mtk.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)
diff --git a/drivers/serial/serial_mtk.c b/drivers/serial/serial_mtk.c
index bce1be8227..11892a8740 100644
--- a/drivers/serial/serial_mtk.c
+++ b/drivers/serial/serial_mtk.c
@@ -46,6 +46,22 @@ struct mtk_serial_regs {
#define UART_LSR_DR 0x01 /* Data ready */
#define UART_LSR_THRE 0x20 /* Xmit holding register empty */
+#define UART_LSR_TEMT 0x40 /* Xmitter empty */
+
+#define UART_MCR_DTR 0x01 /* DTR */
+#define UART_MCR_RTS 0x02 /* RTS */
+
+#define UART_FCR_FIFO_EN 0x01 /* Fifo enable */
+#define UART_FCR_RXSR 0x02 /* Receiver soft reset */
+#define UART_FCR_TXSR 0x04 /* Transmitter soft reset */
+
+#define UART_MCRVAL (UART_MCR_DTR | \
+ UART_MCR_RTS)
+
+/* Clear & enable FIFOs */
+#define UART_FCRVAL (UART_FCR_FIFO_EN | \
+ UART_FCR_RXSR | \
+ UART_FCR_TXSR)
/* the data is correct if the real baud is within 3%. */
#define BAUD_ALLOW_MAX(baud) ((baud) + (baud) * 3 / 100)
@@ -175,6 +191,9 @@ static int mtk_serial_probe(struct udevice *dev)
/* Disable interrupt */
writel(0, &priv->regs->ier);
+ writel(UART_MCRVAL, &priv->regs->mcr);
+ writel(UART_FCRVAL, &priv->regs->fcr);
+
return 0;
}
@@ -248,6 +267,8 @@ static inline void _debug_uart_init(void)
priv.clock = 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);
}
--
2.17.1
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