Re: [PATCH] arm64: dts: rockchip: Change serial baud rate for Pinephone Pro to 1.5 MB

Javier Martinez Canillas
2023-07-28T23:06:05Z

Maya Matuszczyk <maccraft123mc@gmail.com> writes:

> Hi Heiko
>
> pt., 28 lip 2023 o 21:00 Heiko Stuebner <heiko@sntech.de> napisał(a):
>>

[...]

>> So far people only reported "breaks my setup". I'm in a pickle here ;-) .
>> Without anybody saying "I want to also move into this direction" I really
>> feel I should not merge a patch that breaks other peoples setups.
>
> Well, I'd prefer 1.5M baud rate as it is more consistent with other Rockchip
> boards and it makes for a much more usable terminal experience when
> logged in, it also doesn't affect boot times when serial is enabled with a
> high loglevel and console on serial as 115200 does.
>
> Though I'm just fine with using kernel's cmdline to set a baud rate.
>

Same, but also what Peter mentioned in this thread:

Peter Geis <pgwipeout@gmail.com> writes:
>
> Good Morning Heiko,
>
> The 1.5M baud is default because the clock structure on rockchip
> devices does not allow a clean 115200 baud. By attempting to force
> 115200, it will always be slightly off (either low or high depending
> on how the driver decided to round). If this actually causes any
> problems is the subject of much debate.
>
> Very Respectfully,
> Peter Geis
>

So that's another argument for setting it to 1.5M. Anyways, I'll just stop
asking for this and set my cmdline to a non-default baud rate and move on.

I was just asking in case there was a decision made on this topic.

--
Best regards,

Javier Martinez Canillas
Core Platforms
Red Hat