2009-07-13 07:52:30     UART speed differs between kernel and u-boot

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2009-07-13 07:52:30     UART speed differs between kernel and u-boot

Jeppe Ledet-Pedersen (DENMARK)

Message: 77123   

 

HiU-Boot 1.1.6-svn (ADI-2007R1)

 

I have check out and compiled the latest uclinux-dist (revision XXX) trunk, but the bootloader and the kernel uses different uart speeds. When the U-Boot environment variable baudrate is set to 57600, the kernel is set to using 38400 bps. If I set baudrate=38400 in U-Boot the kernel uses 19200 bps. I use U-Boot 1.1.6-svn (ADI-2007R1). Do I need to upgrade to a newer version of U-Boot?

 

I have tried both compiling myself and using the precompiled uImage-SVN-r8437-bf537-stamp image.

 

Any help is appreciated

 

BR,

 

Jeppe

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2009-07-13 08:18:00     Re: UART speed differs between kernel and u-boot

Jeppe Ledet-Pedersen (DENMARK)

Message: 77124   

 

Modifying the bootargs to the following seems to work:

set bootargs root=/dev/mtdblock0 rw earlyprintk=serial,uart0,57600 console=ttyBF0,57600

 

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2009-07-13 08:20:54     Re: UART speed differs between kernel and u-boot

Robin Getz (UNITED STATES)

Message: 77125   

 

Jeppe:

 

The kernel will use whatever you tell it to. There is no default (that I'm aware of).

 

Check out:

 

https://docs.blackfin.uclinux.org/doku.php?id=bootloaders:u-boot:env&s[]=bootargs

 

look for:

 

console=ttyBF0,57600

 

-Robin

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2009-07-13 08:29:00     Re: UART speed differs between kernel and u-boot

Jeppe Ledet-Pedersen (DENMARK)

Message: 77126   

 

Yeah, I figured that out Thanks for the help anyway.

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