[PATCH 06/16] serial: mvebu-uart: add soft reset at probe

[Miquel Raynal <miquel.raynal@free-electrons.com>]

From: Allen Yan <yanwei@marvell.com>

The existing UART driver relies on the bootloader to initialize the
port(s). However, the secondary uart port may not be initialized
properly in early boot stage. This patch adds the UART soft reset when
probing, for all ports.

Signed-off-by: Allen Yan <yanwei@marvell.com>
Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
---
 drivers/tty/serial/mvebu-uart.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c
index 82438884af1e..da756cfec0bb 100644
--- a/drivers/tty/serial/mvebu-uart.c
+++ b/drivers/tty/serial/mvebu-uart.c
@@ -653,6 +653,11 @@ static int mvebu_uart_probe(struct platform_device *pdev)
 	port->private_data = mvuart;
 	platform_set_drvdata(pdev, mvuart);
 
+	/* UART Soft Reset*/
+	writel(CTRL_SOFT_RST, port->membase + UART_CTRL(port));
+	udelay(1);
+	writel(0, port->membase + UART_CTRL(port));
+
 	ret = uart_add_one_port(&mvebu_uart_driver, port);
 	if (ret)
 		return ret;
-- 
2.11.0