[PATCH] PL011: don't force baud rate of 38400 bps

[PATCH] PL011: don't force baud rate of 38400 bps

[Andre Przywara]

The PL011 driver currently sets the baudrate to a hardcoded value of
38400 bits/second. This will break Calxeda Midway, which uses 115200
bps.
Instead don't tinker with the baud rate register at all and rely on
the firmware or bootloader setting the correct value in here.
This works fine on Versatile Express and Calxeda Midway.

Signed-off-by: Andre Przywara <andre.przywara@linaro.org>
---
 xen/drivers/char/pl011.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xen/drivers/char/pl011.c b/xen/drivers/char/pl011.c
index 8e90520..0e1eb64 100644
--- a/xen/drivers/char/pl011.c
+++ b/xen/drivers/char/pl011.c
@@ -229,7 +229,7 @@ static int __init pl011_uart_init(struct dt_device_node *dev,
     uart = &pl011_com;
 
     uart->clock_hz  = 0x16e3600;
-    uart->baud      = 38400;
+    uart->baud      = BAUD_AUTO;
     uart->data_bits = 8;
     uart->parity    = PARITY_NONE;
     uart->stop_bits = 1;
-- 
1.7.12.1

Re: [PATCH] PL011: don't force baud rate of 38400 bps

[Ian Campbell]

On Tue, 2013-08-13 at 17:12 +0200, Andre Przywara wrote:
> The PL011 driver currently sets the baudrate to a hardcoded value of
> 38400 bits/second. This will break Calxeda Midway, which uses 115200
> bps.
> Instead don't tinker with the baud rate register at all and rely on
> the firmware or bootloader setting the correct value in here.
> This works fine on Versatile Express and Calxeda Midway.

Right. People who want Xen to tinker with the baud rate should fix:
    if ( strcmp(config, "") )
    {
        early_printk("WARNING: UART configuration is not supported\n");
    }
to actually understand dtuart=serial0,115200n8 type things.

> Signed-off-by: Andre Przywara <andre.przywara@linaro.org>

acked + applied.