[Savage40] Small video glitches with savage snapshot

[Tim Roberts]

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.

-- 
- Tim Roberts, timr at probo.com
  Providenza & Boekelheide, Inc.