On Fri, 25 Jan 2013, Wolfgang Denk wrote:
Dear Woody Wu,
In message CAAsE_ue4VffAioQWzHPpyOZmzoFk9E5S7jj2+2BZuiK=C5yXtA@mail.gmail.com you wrote:
I want to firstly get a picture to basically understand how u-boot work, especially on an ARM9 based board. I think not everyone who want to understand u-boot has to read the full code. Thank.
This depends on your definition of "understanding". On a highlevel, you might start with reaing and digesting the manual, eventually trying out how U-Boot works on some (real or emulated) board.
if i can jump in, a good way to start playing is to configure and build for the "sandbox" architecture so you can run it on your x86 system. for the benefit of a couple friends, i whipped together a wiki page for that here:
http://www.crashcourse.ca/wiki/index.php/U-Boot_sandbox
very simple but enough to get you started, and you can match up running the commands with the underlying code.
rday