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

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




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>
---


--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,\na Linux Foundation Collaborative Project




[Index of Archives]     [Kernel Newbies]     [Security]     [Netfilter]     [Bugtraq]     [Linux PPP]     [Linux FS]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Samba]     [Video 4 Linux]     [Linmodem]     [Device Mapper]     [Linux Kernel for ARM]

  Powered by Linux