From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stefano Babic <sbabic@denx.de>
Date: Tue, 02 Nov 2010 17:01:59 +0100
Subject: [U-Boot] Add video support for mx51evk
In-Reply-To: <20101102133426.88B011522C0@gemini.denx.de>
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	<20101102083526.685BE1524F4@gemini.denx.de>
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	<20101102094201.869A81522C0@gemini.denx.de>
	<4CCFDEBA.2070203@denx.de>
	<20101102133426.88B011522C0@gemini.denx.de>
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On 11/02/2010 02:34 PM, Wolfgang Denk wrote:

>> Because each board uses a different LCD with a different resolution, and
>> this requires a different amount of memory. This is not different as we
>> see in Linux, because the framebuffer properties are set in the board
>> file before to be passed to the framebuffer driver.
> 
> Well, if _that_ was what we are using, the memory requirements were
> fixed, and we could use compile-time constants.

I was not complete: a single board can be connected to several LCDs, of
course not at the same type. The decision which LCD must be used should
be taken baing on an environment variable.

> 
> But what you discussed before was the option to _switch_ resolutions,
> so there has to be a way to select the cosen resolution (in an
> environment variable?),

Yes, this is what I meant....

> and then this setting is used for the memory
> calculations.

Correct.

> 
> And then the calculation depends only on the current setting - which
> is _not_ board dependent.

Yes, calculation is not board dependent and must remain in lcd_setmem().
What I meant as "board dependent" is really the LCD settings, in terms
of display resolution and bits x pixel. The proposed wek function can
set the panel_info structure, that lcd_setmem() uses for computation.

> 
> Boards would start with a (board dependent) default setting, though.

Yes. What we need is a way to get the board default setting to allow
lcd_setmem() to compute the required memory.

Best regards,
Stefano Babic

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