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SubjectATI Radeon DIRECTCOLOR -> TRUECOLOR patch
I wrote this patch several months ago against 2.6.27.4 out of personal 
preference (I don't think radeonfb has changed enough that it would fail
against the current 2.6.28 all that much):

I'm pasting the URL here to avoid another round of discussion on whether
or not my Mozilla Thunderbird client is mangling the patch:
http://nerdgrounds.com/linux-patches/linux-aty-force-truecolor.patch

I don't know about you but when I ask the framebuffer to set up 16-bit
or 32-bit RGB modes I expect a video mode to be set up with R, G, and B
mapped linearly so that I can display images properly, not some odd
"directcolor" mode that seems to serve no other purpose than to avoid a
few shifts converting the fbcon palette to an RGB triplet.

Looking at radeonfb: setting the framebuffer palette is accomplished by
converting fbcon's RGB to 16bpp and storing that in a lookup table.
Rendering of text for fbcon is done by referring to that lookup table,
because radeonfb provides the 16bpp RGB values. So what exactly is
abusing the palette/gamma registers to make a nonstandard RGB ramp
supposed to accomplish? Is something like this that might make an
infrequently called function like setcolor() 10 nanoseconds faster
really worth it?

When my software running and periodically showing what dvgrab last wrote
to disk the last thing I want clients to see when walking by is a bad
acid trip rendition of what we're filming on camera just because
radeonfb decided to use DIRECTCOLOR and some weird RGB ramp.

This patch changes radeonfb to remove DIRECTCOLOR behavior and act like
a proper TRUECOLOR framebuffer. I consider it a cleaner option than
having to use KD_GRAPHICS (XFree86), which locks out the framebuffer
console, or CMAP ioctls (mplayer), which makes the mapping correct but
then makes the framebuffer console's text dark purple and hard to see.

So far I've tested on three machines that I know have ATI-based video
chipsets:
An AMD64 dual-core 32-bit system, and two ppc-based machines, one a
mac mini and the other a Powerbook G4.

If anyone still needs this weird DIRECTCOLOR behavior I'd be willing to
make the patch into one that allows you to choose as an option in "make
menuconfig"

and... a quick glance reveals that nvidiafb pulls this stunt too. anyone
want a patch for that too?



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