Getting the kernel to let go of my UART!

[Oleksandr Tymoshenko]

Dustin Marquess (dmarquess at gmail.com) wrote:
> Okay, maybe the console thing was a red herring then.
> 
> It's not marking it as a console at all anymore, but something is
> still locking the baud rate to 115200.  Even though stty and minicom
> are both set to 9600, anything set/received at 9600 doesn't work/is
> garbled.  If I set it to 115200, it works fine.  I had wrongly assumed
> it was because of it marking it as a console (since the console line
> in dmesg said 115200).
> 
> Device map? enable_uart=1 aka core_freq= maybe? I'll try tinkering..

It might be a problem with the driver itself. From a quick glance,
PL011 driver sets baudrate only if it has reference clock frequency
which doesn't seem to be the case for RPi. If reference clock
frequency is unknown divider register is left untouched.

According to this document: http://elinux.org/RPiconfig you can
set initial baudrate in config.txt using init_uart_baud variable

-- 
gonzo