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

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.