[U-Boot-Users] [RFD] Consistent debugging output structure

[Wolfgang Denk]

In message <20030322102847.GF28544 at pengutronix.de> you wrote:
> On Wed, Mar 19, 2003 at 07:32:07PM +0100, Robert Schwebel wrote:
> > I would like to discuss the current state of the u-boot debug output
> > code. Nearly every C file in the source tree implements it's own way
> > of outputting debug messages during development, and most of them do
> > it by using Yet Another #ifdef Desert (TM). 
> 
> I've already discussed that with Wolfgang (no idea why the mail needed
> several days to hit the list) and he wants to use the debug() macro
> instead, which is ok for me. 
> 
> What we don't agree on is if we need several debug levels. What do the
> others think? For more complex drivers like the ethernet ones this is
> really useful. 

I think that several  debug  levels  built  into  a  debug  mechanism
(usually  combined  with  some logging features) makes a lot of sense
for an application-type system or product.  It  is  useful  when  the
software  structure  is  pretty  much  constant,  and when there is a
separation between "developers" and "users".

I want the U-Boot design to keep  an  eye  on  efficiency  and  small
memory footprint. Several debug levels may seem useful here and there
(in  which case they are trivial to add based on the existing debug()
macro), but in general they are just overkill.

Those parts where debug printout is really needed are  too  much  CPU
and board dependend anyway.


Yes, I agree, new code should not introduce it's own  "#ifdef  DEBUG"
stuff any more, but use debug() instead - but this is IMHO one of the
"nice to have" issues, not a really important issue.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd at denx.de
I know engineers. They love to change things.             - Dr. McCoy