Re: PROBLEM: 2.6.29.2 - AGP doesn't work anymore on my nforce2

["Michel Dänzer" <michel@daenzer.net>]

On Mon, 2009-05-04 at 18:23 +0200, Karsten Mehrhoff wrote:
> On Mon, 04 May 2009 17:07:40 +0200, Michel Dänzer wrote:
> > On Mon, 2009-05-04 at 08:31 +0200, Karsten Mehrhoff wrote:
> >> On Mon, 04 May 2009 03:41:51 +0200, Shaohua Li wrote:
> >>> On Fri, May 01, 2009 at 09:22:19PM +0800, kawime@gmx.de wrote:
> >>>>> On Thu, 2009-04-30 at 17:59 -0700, Andrew Morton wrote:
> >>>>>> On Thu, 30 Apr 2009 10:51:47 +0200
> >>>>>> Karsten Mehrhoff wrote:
> >>>>>>
> >>>>>>> [1.]
> >>>>>>> PROBLEM: No more agp card functionality with the patch 2.6.29.2 of
> >>>>>> 'a/drivers/char/agp/generic.c'
> >>>>>>>
> >>>>>>> [2.]
> >>>>>>> I compiled the kernel 2.6.29.2 with my .config of 2.6.29.1 and run
> >>>>>> into problems with the speed of my ATI RADEON 9600 (rv350)
> >>>>>>>
> >>>>>>
> >>>>>
> >>>>> Is your problem speed issue ? ie just a slowdown ? Or does AGP stop
> >>>>> working with this patch ? Slowdown is expected from this patch but
> >>>>> it should hurt too much.
> >>>>>
> >>>>
> >>>>                        2.6.29.1  | 2.6.29.2
> >>>>                         --------  |  --------
> >>>> glxgears             ~ 2900 FPS  |  ~ 75 FPS
> >>>> glxgears -fullscreen ~  500 FPS  |  ~ 11 FPS
> >>> Does this patch alone give so huge slowdown? From my little knowledge,
> >>> xserver
> >>> does agp pages allocation only at startup.
> >>
> >> I only reverted this patch in the source file  
> >> (/drivers/char/agp/generic.c) and got back my old speed on 2.6.29.2.
> >
> > Is the DRI enabled in both cases? Compare the Xorg.0.log file and the
> > output of
> >
> > dmesg|grep -e agp -e drm
> >
> 
> 
> *********************************
> 2.6.29.2 (original) 
> *********************************
> 
> $ dmesg|grep -e agp -e drm
> $ dmesg|grep agp
> [    0.861997] Linux agpgart interface v0.103
> [   10.893793] agpgart: Detected NVIDIA nForce2 chipset
> [   10.939070] agpgart-nvidia 0000:00:00.0: AGP aperture is 64M @ 0xe0000000

No drm lines?


> $ glxinfo | grep direct
> direct rendering: Yes

This is not a sufficient test anymore since swrast_dri.so is direct
rendering but not hardware accelerated. Something like

glxinfo|grep render

can be used to verify both direct rendering and hardware acceleration
(the latter but not the former is also possible with AIGLX).


> (EE) RADEON(0): [agp] AGP failed to initialize. Disabling the DRI.

[...]

> For me it seems that agp failed to initialize because of the patch.

Indeed.


-- 
Earthling Michel Dänzer           |                http://www.vmware.com
Libre software enthusiast         |          Debian, X and DRI developer