experimental splash screen support

Werner Almesberger werner at openmoko.org
Tue Feb 20 17:34:56 CET 2007

Harald Welte wrote:
> Can you do some size experiments on raw framebuffer images, compressed
> with gzip?  If that gives us sufficient results, it might be an
> alternative.

This look pretty good: the "raw" image shrinks from 614400 bytes to
17216 with gzip -9. For comparison, the gzip'ed BMP is 16707 bytes.

I've just added support for this:

- make the image:
  ./imghs.pl  | gzip -9 >out.gz

- load it:
  load_binary wherever/out.gz 0x32000000

- use it:
  unzip 0x32000000 0x33d00000 0x96000

This even seems to be a bit faster than BMP.

> Firstly, I don't think that this is particularly important.  Secondly, I
> think it can be done by redefining the palette in a way that some
> (currently blacked out) colour suddenly appears on-screen.

Ah, but the u-boot frame buffer is still configured as 16 bit RGB.
I didn't touch that part :)

>> One problem is that bootcmd is now getting so long that we exceed the
>> maximum number of command line arguments. So I've increased them from
>> 16 to 64.
> mh, will have to look at that.

If we drop the second image, then we don't need this increase now,
but it can't hurt to keep it, considering how much we're putting
into bootcmd these days already.

> I would either stay with one, or do the palette trick.

Yep, if we get rid of bootdelay for regular use, then we don't need
a second image. In any case, all the support needed for this is in
"user space".

Cheers, Werner

 / Werner Almesberger, Buenos Aires, Argentina     werner at almesberger.net /

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