Stefano Babic sbabic at denx.de
Fri Jun 20 10:43:11 CEST 2014

Hi Larry,

On 18/06/2014 00:35, Larry Baker wrote:

> I experience the unrequested U-Boot prompt even when the FTDI cable
> is attached.  I saw many suggestions for fixes on various web pages,
> and none of them seemed to work for everyone that tried them.  The
> fix to slightly harden U-Boot's behavior worked.
> I agree completely with Wolfgang's opinion about either the design or
> quality of the hardware.  Is this a lower quality hobbyist device?
> Perhaps.  It is also affordable, very popular, and very useful.  This
> is a dedicated (~TTL, not RS-232) console port, not typically exposed
> to the user of the device, whose sole purpose is to interact directly
> with the embedded U-Boot and Linux.  Is it really such a good thing
> that U-Boot is so promiscuous in what it is willing to accept as an
> invitation to converse?  I think it is good defensive programming to
> be a bit pickier.  What is the harm?
> I do not wish to argue with anyone about it.  I can make the change
> for myself and I will certainly document the reason I am making the
> change in my notes.

The best thing you can do is to send an appropriate patch to u-boot ML
and in CC to the TI Maintainer (Tom Rini), asking for review. Adding
 CONFIG_AUTOBOOT_DELAY_STR change behavior for other boards, too,
because am335x_evm.h is used by several boards, not only BBB. Which
board is running is verified at runtime, see board_is_bone() in
am335x/board.c code. The same hardware issue seems that does not affect
other boards. Maybe you can add a runtime check and change the behavior
only on BBB.

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

More information about the eldk mailing list