Re: [PATCH] tty: serial: qcom_geni_serial: 115.2 is a better console default than 9600

[Akash Asthana]

On 9/11/2020 8:30 PM, Douglas Anderson wrote:
> Commit c5cbc78acf69 ("tty: serial: qcom_geni_serial: Initialize baud
> in qcom_geni_console_setup") fixed a bug by initting a variable that
> was used in some cases without initialization.  However, the "default"
> baud rate picked by that CL was probably not the best choice.  The
> chances that anyone out there is trying to run a system with kernel
> messages piped out over a 9600 baud serial port is just about nil.
> Console messages are printed in a blocking manner.  At 9600 baud we
> print about 1 character per millisecond which means that printing a
> 40-byte message to the console will take ~40 ms.  While it would
> probably work, it's going to make boot _very_ slow and probably cause
> the occasional timeout here and there in drivers (heck, even at 115200
> console delays can wreck havoc).
>
> This has already bit at least two people that I'm aware of that tried
> to enable serial console by just adding "console=ttyMSM0" (instead of
> "console=ttyMSM0,115200n8") to the command line, so it seems like it'd
> be nice to fix.
>
> Let's switch the default to 115200.
Reviewed-by: Akash Asthana <akashast@xxxxxxxxxxxxxx>
> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
> ---
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