[U-Boot-Users] [RFC] Splash image

[Rodolfo Giometti]

On Wed, Jul 18, 2007 at 09:40:28AM -0400, Joey Oravec wrote:
> "Rodolfo Giometti" <giometti at enneenne.com> wrote in message 
> news:20070718083012.GE4836 at enneenne.com...
> > I'm planning to review the splash image support and in order to do that
> > my next steps should be:
> >
> > 1) Remove the logo support.
> 
> As long as it's modular, I agreed because the two functions are nearly 
> identical. It's important to add/remove code to keep the size down. Probably 
> should test for a pointer to a compressed (gzip) image, uncompress, then 
> call the bmp_display.

I think we should remove it definitely... it's just doubled code.

> > 2) Rewrite the lcd_display_bitmap() in order to be more portable
> > across several BPP values.
> 
> Keep it modular; have a bitmap_display(addr, x, y) robust to bpp that is 
> called from an lcd_display_splash_screen(). Account for 24-bit LCDs and 
> files. The bit-per-pixel data structure was a poor-fit with 24-bit, and I 
> didn't even try to support colormapped files on a truecolor display. Great 
> idea because it might save a ton of flash to display an 8bpp image on a 
> 24bpp display.
> 
> 3. If there's an overall flash savings, it would be nice to support GIF, 
> PNG, or some other format smaller than a BMP. How complex is the parsing, 
> and would it be a net savings on flash?

I think we should support just one format for two reasons:

1) Supporting just one format keep the code smallest.

2) We have "convert". :)

> 4. Account for text overlay on splash screen. There are callbacks for bootup 
> progress, and it's nice to lcd_printf() the status to some rectangle on the 
> screen. Even better if it scrolls or clears nicely.
> 
> 5. Document and improve the videolfb ATAG. I hardcode my framebuffer to the 
> end of RAM, don't tell linux to use that memory, and pass the info to linux. 
> The display still flickers until you remove the re-initialization, but at 
> least Linux won't move and therefore clobber the contents of the 
> framebuffer.

I dislike this feature. :) IMHO I think it introduces several problems
and complications whose can be avoided just defining a boot logo into
Linux... however it could be keep into some consideration.

Thanks for your suggestions,

Rodolfo

-- 

GNU/Linux Solutions                  e-mail:    giometti at enneenne.com
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