[U-Boot] Question about baud rate

Detlev Zundel dzu at denx.de
Thu Nov 17 18:50:04 CET 2011


Hi Dan,

> I'm using a board similar to canyonlands with a ppc460ex. The baud rate 
> for ttyS0 is set to 115200 by the console= bootarg, but I'd also like to 
> set ttyS1-3 to 115200 also.

Why doe you want to setup this parameters "from the outside"?  Really
only the serial device used for a console needs to be setup by
firmware.  All other serial devices should be initialized by the user
space programs using them.

> For each of the three uarts, the device tree has the following line:
>
> current-speed = <0>; /* Filled in by U-Boot */

Checking current U-Boot code, I believe this comment is simply wrong.  I
cannot see any part in the canyonlands / or generic 4xx infrastructure
that fixes up these properties.  Maybe Stefan can comment on this
though.

> How do I go about configuring u-boot to fill these with the baud rate I 
> choose?
>
> Sorry for the silly question!

I don;t think its a silly question, but I also think that you do not
need the configuration ;)

Cheers
  Detlev

-- 
One of the main causes of the fall of the Roman Empire was that, lacking zero,
they had no way to indicate successful termination of their C programs.
                                        -- Robert Firth
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