[Linux-fbdev-devel] scroll modes

[Knut P. <Knu...@t-...>]

Hi everybody,

Is there a patch for "true ywrap" scrolling?

Lets have a look at a mode xres=vxres=1024, yres=768, depth=32. As there
is 8 Mb of available memory, we can use a vyres of 2048. With an 8x16 font
this gives exactly 128 lines of text in virtual memory, 48 lines are 
displayed.

Current code stops to ypan at text line 80, moves image data to the 
beginning of the
video memory and continues. The frequent calls to copyarea are a major 
cause of
slowing down at high image depths.

Optimal scrolling for the cyberblade would mean nothing but to emit new 
lines
with hwaccel imageblit up to the very end of video memory and to ypan 
accordingly.
There is no need for moving data around in video memory or to redraw the 
screen
as the cyberblade hardware handles wrapping at the end of the video 
memory perfectly
fine.

cu,
 knut