[Savage40] Small video glitches with savage snapshot

[Bjorn Knutsson]

On 11 Apr 2005 10:01, Tim Roberts wrote:
> Bjorn Knutsson wrote:
> 
> >Well, that caused the entire screen content to be skewed, with garbage
> >at the end. I guess this might be consistent with:
> >
> >(--) SAVAGE(0): 1408x1050 TFT LCD panel detected and active
> >(--) SAVAGE(0): - Limiting video mode to 1408x1050
> >
> >As far as I know, the panel is only 1400x1050, if those extra 8 pixels
> >exists, I guess they're not on the actual panel, so if it fills a
> >linear buffer with 1400x1050 pixels, and 8 pixels every line goes
> >missing somewhere, then that would explain both why there's a skew,
> >and why it ran out of pixels at the end of the screen.
> >  
> >
> 
> The Savage requires that the width of the frame buffer be a multiple of 
> 16 pixels.  1400 is not a multiple of 16.  The CRTC and the graphic 
> engine are fully capable of handling a mode in which there is padding on 
> the right, although I don't know about the DRI extensions.
> 
> The driver reads that width and height information directly from the 
> BIOS.  I don't actually know whether the BIOS is lying to us to satisfy 
> the multiple-of-16 thing, or if the panels really are 1408 pixels but 
> it's too hard to pronounce.

The panel physically does not have those extra pixels, at least not
ones that a physical inspection of the panel would reveal.

/Bjorn