[ELDK] Disable any messages to console

[Detlev Zundel]

Hi Giuseppe,

> I have a ELDK system running on a ARM9 board. By U-Boot I use 
> "console=ttyAM0,115200" parameter for linux kernel. In that way the 
> Linux console is the first serial port and I can see kernel messages, 
> login and so on.
>
> I want to use both serial ports available for purposes other than see 
> kernel messages and login (I can always login by telnet). 
>
> So I disable the login by serial ports and pass the "quiet" parameter 
> to linux kernel.
> In this way, during the boot, I don't see any kernel message and I 
> can't login anymore by serial port, but only by telnet.
> However some messages are send to the serial port (I think linux 
> consider ttyAM0 as the console and when he want print messages to 
> it). For example, when I login by telnet, I see the message about 
> root login on the serial port.
>
> I tried to pass 'console=ttyAM25,115200', but the kernel stops (I 
> think, because I don't see anything, but telnet doesn't work 
> anymore).

Well, specifying a non-existant device is not really nice.  Although it
shouldn't crash the kernel, probably very little testing went into such
cases...

> How can I completely disable messages to ttyAM0 by kernel?

There is an easy answer, simply do not provide any "console=" parameter
at all.  A standard Linux kernel will not magically connect consoles to
any serial ports, so this will do what you want.

Cheers
  Detlev

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I think that level of generalization is too abstract for useful thinking.
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