[U-Boot] How to silence the output of U-Boot

[U-Boot] How to silence the output of U-Boot

[Frank Ihle]

Hi everyone,

I searched the Internet but the help I found didn't work. I hope someone here may know how to fix it, here's the situation:

I have this ARM9 SAM9G25 which is accessed by its ttyS0. I
 want to disable all of the output, that was made during the U-Boot (v. 2010.06) 
boot, to decrease the CPU's load. Therefore there is the 


  setenv silent 1



parameter, which i put into the BOOTCMD string like:



  #define CONFIG_BOOTCOMMAND   " setenv silent 1;" \

"bootm "



and there is (as mentioned in the Readme.silent http://git.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=blob;f=doc/README.silent;hb=v2013.10 ) the
#define CONFIG_SILENT_CONSOLE
#define CONFIG_SYS_DEVICE_NULLDEV
#define CONFIG_SILENT_CONSOLE_UPDATE_ON_SET


command, neither one is working (the lines printed out are still the same and the boot time didn't change). Whereas the 
         setenv verify n
is working, just to give an example.

Does somebody see the error ?

BTW
 (I'm not sure if this is related to this) in the referenced link there 
is the information, that u-boot sets the kernel command line to 
"console=" so that in the end there will be no output for the kernel 
too, but that didn't happen and it doesn't even happen if i force to 
boot Linux with "console=" in the default Linux command line string
Thanks for your help.
Kind Regards,
Frank

[U-Boot] How to silence the output of U-Boot

[Stefano Babic]

Hi Frank,

On 07/03/2014 10:17, Frank Ihle wrote:
> Hi everyone,
> 
> I searched the Internet but the help I found didn't work. I hope someone here may know how to fix it, here's the situation:
> 
> I have this ARM9 SAM9G25 which is accessed by its ttyS0. I
>  want to disable all of the output, that was made during the U-Boot (v. 2010.06) 
> boot, to decrease the CPU's load. Therefore there is the 
> 
> 
>   setenv silent 1
> 

Your U-Boot is too old.

> 
> 
> parameter, which i put into the BOOTCMD string like:
> 
> 
> 
>   #define CONFIG_BOOTCOMMAND   " setenv silent 1;" \
> 
> "bootm "
> 
> 
> 
> and there is (as mentioned in the Readme.silent http://git.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=blob;f=doc/README.silent;hb=v2013.10 ) the

As you see, patches was integrated in 2013. You are running an old
U-Boot version, when silent was not supported. Please update to 2014.01
or (better) use the current git tree.

> BTW
>  (I'm not sure if this is related to this) in the referenced link there 
> is the information, that u-boot sets the kernel command line to 
> "console=" so that in the end there will be no output for the kernel 
> too, but that didn't happen and it doesn't even happen if i force to 
> boot Linux with "console=" in the default Linux command line string

Usually, it helps if you pass "quiet" to the kernel command line.

Best regards,
Stefano Babic


-- 
=====================================================================
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-53 Fax: +49-8142-66989-80 Email: sbabic at denx.de
=====================================================================

[U-Boot] Antw: Re: How to silence the output of U-Boot

[Frank Ihle]

>Your U-Boot is too old.
Are there any patches for the my version? I guess the new version is better but I'm forced to use this version
 
>Usually, it helps if you pass "quiet" to the kernel command line.
 
quiet is working but the "console=" does not, but this is not a problem of U-Boot, I just thought they have something in common.

Kind Regards
 
Frank

[U-Boot] Antw: Re: How to silence the output of U-Boot

[Stefano Babic]

On 12/03/2014 10:02, Frank Ihle wrote:
>> Your U-Boot is too old.
> Are there any patches for the my version? I guess the new version is better but I'm forced to use this version

You have all patches in the git tree. You can try to back porting
patches back to your version, but, sincerely, I do not think it is a
good idea.

Best regards,
Stefano Babic

-- 
=====================================================================
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-53 Fax: +49-8142-66989-80 Email: sbabic at denx.de
=====================================================================