Re: [PATCH] smart blitter usage for scrolling (cleaned)

["Antonino A. Daplas" <adaplas@gmail.com>]

On Fri, 2007-05-11 at 08:42 +0200, Krzysztof Helt wrote:
> From: Krzysztof Helt <krzysztof.h1@wp.pl>
> 
> This patch replaces the current SCROLL_MOVE method with smarter
> method using the same logic as the SCROLL_REDRAW method. This
> brings these two methods much closer in performance and benefits
> all framebuffers which uses the SCROLL_MOVE method.
> 
> Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
> 
> ---
> 
> This version does not merge blits and does not uses ifdefs. The
> patch was diffed against linux-2.6.21-git11
> 
> Regards,
> Krzysztof
> 
> diff -urp linux-2.6.21.orig/drivers/video/console/fbcon.c
> linux-2.6.21/drivers/video/console/fbcon.c
> --- linux-2.6.21.orig/drivers/video/console/fbcon.c	2007-05-09
> 16:56:07.936744076 +0200
> +++ linux-2.6.21/drivers/video/console/fbcon.c	2007-05-10
> 21:00:22.685633709 +0200
> @@ -1704,6 +1704,61 @@ static void fbcon_redraw_move(struct vc_
>  	}
>  }
>  
> +static void fbcon_redraw_blit(struct vc_data *vc, struct fb_info
> *info,
> +			struct display *p, int line, int count, int ycount)
> +{
> +	int offset = ycount * vc->vc_cols;
> +	unsigned short *d = (unsigned short *)
> +	    (vc->vc_origin + vc->vc_size_row * line);
> +	unsigned short *s = d + offset;
> +	struct fbcon_ops *ops = info->fbcon_par;
> +
> +	while (count--) {
> +		unsigned short *start = s;
> +		unsigned short *le = advance_row(s, 1);
> +		unsigned short c;
> +		int x = 0;
> +		unsigned short attr = 1;
> +
> +		do {
> +			c = scr_readw(s);

#####
> +			if (attr != (c & 0xff00)) {
> +				attr = c & 0xff00;
> +				if (s > start) {
> +					ops->bmove(vc, info, line + ycount, x, line, x, 1, s-start);
> +					x += s - start;
> +					start = s;
> +				}
> +			}
#####

The code block above is probably not needed. It just checks if the
attribute of the character (ie the color) has changed.  This is required
for putcs, but is unnecessary for bmove.

Tony



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