Re: [Linux-fbdev-devel] [PATCH] radeonfb(): memmove() fix -- this one works ;-)

[Antonino A. D. <ad...@ho...>]

On Thu, 2004-04-22 at 02:13, James Simmons wrote:
> 
> > > > This is true for PCI/AGP, but may not be true for unified memory systems.
> > >
> > > Right, but that confirms my opinion that the choice of the technique used
> > > shall be under control of the driver
> > 
> > Agreed. So a hint would be the most appropriate.
> 
> Hi Antonino. Haven't heard from you in a while.

Yeah, been busy.

> 
> I agree. What if we add to vmode in struct fb_screeninfo.
> We have 
> 
> FB_VMODE_YWRAP		256
> FB_VMODE_SMOOTH_XPAN	512
> 
> We can add more fields. Of course we have to figure out what the common 
> case would be.
> 

We can add:

FB_VMODE_YPAN
FB_VMODE_REDRAW /* will use imageblit */
FB_VMODE_MOVE   /* will use copyarea */

Personally, I think FB_VMODE_REDRAW should be the default as it is 
faster than FB_VMODE_MOVE for most PCI cards.

Just to be clear.

1.  If without a ypan or ywrap, fbcon can either do a redraw or a move

2.  If with ypan or ywrap, then fbcon can only do a move.

Ypan + redraw (FB_VMODE_MOVE | FB_VMODE_REDRAW) is not supported, and I
consider this combination to give the fastest and smoothest scrolling
action if driver does not have any hardware acceleration in most cards.
Perhaps this can be added?

Tony