Re: [PATCH] pxafb: Add support for other palette formats

[Paulo Marques <pmarques@grupopie.com>]

Lothar Wassmann wrote:
> Hi,

Hi,

>> I assume the "red 6@16" is a typo for "red 6@12", since the "3 byte / 
>> green 6@6 and blue 6@0" match exactly the 18bpp packed format. Even 
>>
> Take a closer look at the actual pixel format of the PXA270.
> The usual graphics packages AFAIK support either packed pixels
> (i.e. 18 bit on screen => 18 bit in memory)

This mode would be quite insane: 16 pixels in 9 words?  :P

No, I don't think there are graphics packages out there supporting this 
mode.

> or unpacked (i.e. 18/24
> or whatever bits => 32 bit in memory).
> The PXA supports either the unpacked pixel format (which is a waste of
> memory especially on embedded systems) 

...but is very good for alignment. Access to any individual pixel is 
always aligned on a 4 byte boundary. So, I guess it depends on the 
application.

> or a strange format which is
> neither: 18bit on screen in 24bit in memory (IOW 4 pixels in 3
> words in memory).

Take a closer look at my post, specially at the "3 byte" part. The mode 
supported by DirectFB is really the packed mode of the PXA270: 18bit on 
screen in 24bit in memory.

-- 
Paulo Marques - www.grupopie.com

"All I ask is a chance to prove that money can't make me happy."

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