Re: [directfb-users] Problems with pixelformat rgba 6/0, 6/0, 6/0, 0/0

[Attilio Fiandrotti <attilio.fiandrotti@gmail.com>]

Ville Syrjälä wrote:
> On Sat, Dec 02, 2006 at 09:59:06PM +0100, Attilio Fiandrotti wrote:
>
> > Ville Syrjälä wrote:
> >
> > > 4bit sounds like vga16fb to me.
> >
> > uhm.. i often noticed we also have vga16fb loaded, which usually gives 
> > us fb1 aside fb0 by vesafb: if fb0 and fb1 were swapped could that be 
> > the cause of this bug?
>
>
> Yes. IIRC vga16fb uses a planar format instead of packed pixels so it 
> would not work with DirectFB even if we had DSPF_LUT4.
>
> Actually... A quick look at the vga16fb code indicates it does support 
> 4bpp and 8bpp packed modes too. So DirectFB could work if a 8bpp mode is 
> selected, ie. having pixelformat=DSPF_RGB332 or pixelformat=DSPF_LUT8 in 
> your directfbrc. Unfortunately vga16fb does have a video memory limit of 
> 16KB in these modes...

Ville, thank you very much for spending time investigating in this: 
tomorrow (hopefully) i'll ask the BR submitter to provide us a syslog, 
so that we can see what's really happening.

In a working debian installer one should have

attilaptop:/home/attilio# ls /dev/fb*
/dev/fb0  /dev/fb1
attilaptop:/home/attilio# cat /proc/fb
0 VESA VGA
1 VGA16 VGA

but something, somewhere, may have lead to a differend fb devices order.

We may not able to fix the g-i there, but we may fallback to the textual 
installer if fb0 is VGA16, preventing crash.

cheers

Attilio