bcm2708_fb: Support for 256 color indexed mode with custom palette?

[maxnet]

Older games that operate in 8 bpp 256 colors mode, expect to be able to choose which colors they want in their palette.
However setting colors does not seem to be implemented. ( bcm2708_fb_setcolreg( ) does nothing for color numbers over 16?)

Is this something that might be added to a future version, or is this not supported by the hardware?

[popcornmix]

I believe it can be supported by hardware, but the palette currently isn't passed through.
If you can point me at simple example code that uses a 8bpp palette mode, I'll look into it.

[maxnet]

Created a minimal example: http://pasteit.com/18040

Should output a Dutch red, white and blue flag, like in this screenshot: http://s13.postimage.org/ithb0hzrb/screenshot_testpng.png

[popcornmix]

Thanks for testcase. Please update and test.

[maxnet]

<< Store palette info where GPU can see it, so 8bpp modes can work. Requires updated start.elf to work properly >>

Is the updated start.elf available for download as well?
firmware repo is 3 days old.

[maxnet]

nvm
I see that the new start.elf is available on Hex's git, just not on https://github.com/raspberrypi/firmware/tree/master/boot

Thanks for the update.
Have tested it, and Duke Nukem 3D looks a lot better now :-)

(Was affraid some other older games may use pallete cycling with a subset of the colors to simulate flowing water and other minor animations.
But checked the SDL fbcon source code and it indeed always sends a colormap with all 256 colors to the kernel.
So your hack should be safe for all games using libSDL for graphics)