[U-Boot] [PATCH] [v2] powerpc: 'monitor' environment variable contains full video configuration

Wolfgang Denk wd at denx.de
Tue Mar 15 20:02:41 CET 2011


Dear Timur Tabi,

In message <4D7F8B3C.4080307 at freescale.com> you wrote:
>
> > Don't try to be more clever than the user.  Instead of helping, you
> > restrict him. That's bad.
> 
> I'm not being more clever.  The code is setting a variable (diubootargs) that is
> guaranteed to be the same video mode that U-Boot is running.  If you want to
> ensure that Linux set to the same video mode, then use the variable.  Otherwise,
> don't use the variable and set the command line manually.

You don't need another variable for setting the video mode, because we
(will) have "video-mode" for that very purpose, that can and shall be
used both in U-Boot and Linux.

> > NAK, NAK, NAK.  All such automatic and unconditional editing is bad
> > and should strictly be avoided.
> 
> You didn't understand my post.  I was saying that I tried to implement it, but
> gave up because it got too complicated.

I did understand your posting. I wanted to tell you that you should
not even try doing such things.

> > Leave the decision which device to use as console to the user.
> 
> That's what the 'monitor' environment variable is for.

"monitor" has nothing to do with the console, right?

typically we (here at DENX) use helper macros like

	setenv addcons 'setenv bootargs ${bootargs} console=${consdev},${baudrate}'
	setenv consdev ttyS0

Then you can have the "addcons" in some command sequence that builds
up the bootargs.

"monitor"? No, this has _nothing_ to do with any console settings.

> >> > 2) The video display needs to be enabled and the U-Boot console needs to be
> >> > routed to it
> > NAK.
> > 
> > Wether the U-Boot console is attached to the serial port or the video
> > console or netconsole or anything else should be left to the user.
> 
> Again, that's what the variable is for.  What's the point of configuring the
> video display if you're not going to enable it?

You misinterpret what I wrote.  Of course we're going to enable the
video display then.

But there is no reason to always and unconditionally put the console
on that device - that is a completely separate and independent
decision.

> > A default setting is OK, but the user must be able to set anything he
> > likes.
> 
> Are we speaking the same language?  It doesn't appear that you're understanding
> anything I'm saying.

And vice versa.  Probably you don't read what I'm writing either.

> I still don't understand what you actually want.

I want that you keep the console settings out of this topic. It has
nothing to do with it.

And I want to make sure that we don't have several environment
variables doing more or less the same thing.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
A Chairman was as necessary to a Board planet  as  the  zero  was  in
mathematics, but being a zero had big disadvantages...
                         - Terry Pratchett, _The Dark Side of the Sun_


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