[U-Boot] [PATCH] dm: serial: Initialize serial console only when it wasn't already configured

[Lukasz Majewski]

It may happen that the MXC serial IP block is performing some ongoing
transmission (started at e.g. board_init()) when the "initr_serial" is
called.

As a result the serial port IP block is reset, so transmitted data is
corrupted:

I2C:   ready
DRAM:  1 GiB
jSS('HH��SL_SDHC: 04 rev 0x0

This patch prevents from this situation, by avoiding re-initialization of
serial IP block (and execution of the same code twice).

I2C:   ready
DRAM:  1 GiB
ID:    unit type 0x4 rev 0x0

This patch is a follow up of following discussions:
http://patchwork.ozlabs.org/patch/820824/
http://patchwork.ozlabs.org/patch/830957/


Signed-off-by: Lukasz Majewski <lukma at denx.de>

---

 drivers/serial/serial-uclass.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/serial/serial-uclass.c b/drivers/serial/serial-uclass.c
index 2e5116f7ce..c345578b36 100644
--- a/drivers/serial/serial-uclass.c
+++ b/drivers/serial/serial-uclass.c
@@ -129,6 +129,9 @@ static void serial_find_console_or_panic(void)
 /* Called prior to relocation */
 int serial_init(void)
 {
+	if (gd->flags & GD_FLG_SERIAL_READY)
+		return 0;
+
 	serial_find_console_or_panic();
 	gd->flags |= GD_FLG_SERIAL_READY;
 
-- 
2.11.0