lkml.org 
[lkml]   [2014]   [Jan]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 4/10] atyfb: set FBINFO_READS_FAST


On Thu, 23 Jan 2014, Linus Torvalds wrote:

> Hmm. You're doing this for Matrix and now the aty driver.
>
> Maybe the problem is at the fbcon level? Depending on
> FBINFO_READS_FAST to decide whether you should scroll or rewrite
> sounds a bit silly: even if a device doesn't have fast reads, maybe it
> has a fast accelerated BLIT operation and scrolls quickly. Should the
> fbcon test perhaps be for FBINFO_READS_FAST _or_ the
> FBINFO_HWACCEL_COPYAREA bits?

Both mach64 and matrox have a hardware bitter that is faster than
rewriting the console - that's why FBINFO_READS_FAST improves performance
for them.

One could improve generic framebuffer core to benchmark the performance of
scrolling using blitter and rewrite and select FBINFO_READS_FAST
automatically...

Mikulas

> I dunno. I didn't actually check the ->bcopy implementations, maybe
> they don't use copyarea. So I'm just going by a general "this feels
> wrong" feeling..
>
> Linus


> On Thu, Jan 23, 2014 at 10:18 AM, Mikulas Patocka <mpatocka@redhat.com> wrote:
> > Set FBINFO_READS_FAST so that the console code uses scrolling instead of
> > rewriting. This improves scrolling speed.
>


\
 
 \ /
  Last update: 2014-01-23 21:21    [W:0.155 / U:0.060 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site