[i945] [Ubuntu-X-Swat] 945GM Unable to load desktop > 2048x2048 with UXA

[noisymime]

Binary package hint: xserver-xorg-video-intel

* I am using the Intel drivers from the X Swat PPA *
xserver-xorg-video-intel: 2.7.1
kernel: 2.6.30

I am currently unable to load a desktop with a resolution great than 2048x2048 using UXA. I understand there is a limitation with my hardware (945GM) that means I cannot use DRI with a resolution greater than this, however with UXA enabled I cannot get a desktop at all.
Error: (EE) intel(0): Cannot support DRI with frame buffer width > 2048.
and am then given options to reconfigure xorg or start in low graphics mode.

I have tried disabling DRI by adding the following to xorg.conf:
Option "DRI" "off"
However the option seems to be ignored and the same error appears. I can find no way to disable DRI and therefore get a desktop with UXA.

In the past the Intel driver would simply disable DRI automatically if you requested a display >2048 however this does now not appear to be the case with UXA. If I switch back to EXA, the desktop (@ 3072x2048) will load fine. The extra resolution is enabled with the following in xorg.conf:
SubSection "Display"
                Virtual 3072 2048
EndSubSection

If I remove the 2nd monitor and load a 1024x768 desktop with UXA everything works fine (Performance is great!) but I can find no way at all to get the larger display with UXA.

ProblemType: Bug
Architecture: i386
DistroRelease: Ubuntu 9.04
Package: xserver-xorg-video-intel 2:2.7.1-0ubuntu1~xup~1
ProcEnviron:
 LANGUAGE=
 LANG=en_AU.UTF-8
 SHELL=/bin/bash
ProcVersion: Linux version 2.6.30-020630-generic (root@zinc) (gcc version 4.2.3 (Ubuntu 4.2.3-2ubuntu7)) #020630 SMP Wed Jun 10 09:45:40 UTC 2009
SourcePackage: xserver-xorg-video-intel
Uname: Linux 2.6.30-020630-generic i686
UnreportableReason: This is not a genuine Ubuntu package

[Haien-liu (haien-liu)]

Created an attachment (id=24806)
xorg conf file

[Haien-liu (haien-liu)]

and it exists with KMS and UMS.

[Gordon Jin (gordon-jin)]

*** Bug 21571 has been marked as a duplicate of this bug. ***

[Bryce Harrington (bryce)]

A backtrace is available here:
http://launchpadlibrarian.net/24551278/ThreadStacktrace.txt

briefly:

#0 0xb78e3309 in drm_intel_bo_reference () from /usr/lib/libdrm_intel.so.1
#1 0xb794588b in i830_set_pixmap_bo (pixmap=0x8465190, bo=0x0)
    at ../../src/i830_exa.c:772
 old_bo = <value optimized out>
#2 0xb7920ab8 in i830_xf86crtc_resize (scrn=0x83efef0, width=1152,
    height=864) at ../../src/i830_driver.c:1178
 new_front = <value optimized out>
 old_front = (i830_memory *) 0x843e810
 mem_box = {x1 = 0, y1 = 0, x2 = 2048, y2 = 864}
 screen = (ScreenPtr) 0x843e350
 old_x = 3120
 old_y = 1050
 old_width = 4096

[Jesse Barnes (jbarnes-virtuousgeek)]

Does this also happen if you just set the accelmethod to none in xorg.conf?

[Haien-liu (haien-liu)]

(In reply to comment #5)
> Does this also happen if you just set the accelmethod to none in xorg.conf?
>

yes，and it does happen without acceleration.

[noisymime (josh-noisymime)]

Binary package hint: xserver-xorg-video-intel

* I am using the Intel drivers from the X Swat PPA *
xserver-xorg-video-intel: 2.7.1
kernel: 2.6.30

I am currently unable to load a desktop with a resolution great than 2048x2048 using UXA. I understand there is a limitation with my hardware (945GM) that means I cannot use DRI with a resolution greater than this, however with UXA enabled I cannot get a desktop at all.
Error: (EE) intel(0): Cannot support DRI with frame buffer width > 2048.
and am then given options to reconfigure xorg or start in low graphics mode.

I have tried disabling DRI by adding the following to xorg.conf:
Option "DRI" "off"
However the option seems to be ignored and the same error appears. I can find no way to disable DRI and therefore get a desktop with UXA.

In the past the Intel driver would simply disable DRI automatically if you requested a display >2048 however this does now not appear to be the case with UXA. If I switch back to EXA, the desktop (@ 3072x2048) will load fine. The extra resolution is enabled with the following in xorg.conf:
SubSection "Display"
                Virtual 3072 2048
EndSubSection

If I remove the 2nd monitor and load a 1024x768 desktop with UXA everything works fine (Performance is great!) but I can find no way at all to get the larger display with UXA.

ProblemType: Bug
Architecture: i386
DistroRelease: Ubuntu 9.04
Package: xserver-xorg-video-intel 2:2.7.1-0ubuntu1~xup~1
ProcEnviron:
 LANGUAGE=
 LANG=en_AU.UTF-8
 SHELL=/bin/bash
ProcVersion: Linux version 2.6.30-020630-generic (root@zinc) (gcc version 4.2.3 (Ubuntu 4.2.3-2ubuntu7)) #020630 SMP Wed Jun 10 09:45:40 UTC 2009
SourcePackage: xserver-xorg-video-intel
Uname: Linux 2.6.30-020630-generic i686
UnreportableReason: This is not a genuine Ubuntu package

[Keith Packard (keithp)]

I've pushed driver fixes for this to master in patch:

d655a3ff423e69c19a5dc07140cbf3caaa32cb86 Remove NoAccel support.

There's an associated fix necessary in the kernel to bump the framebuffer limit from 2048 to 4096 for KMS which should land shortly.

[Geir Ove Myhr (gomyhr)]

(In reply to comment #7)
> I've pushed driver fixes for this to master in patch:
>
> d655a3ff423e69c19a5dc07140cbf3caaa32cb86 Remove NoAccel support.

Shouldn't the NoAccel option also be removed from man/intel.man then?

[Keith Packard (keithp)]

> Shouldn't the NoAccel option also be removed from man/intel.man then?

Not quite -- the i810/i815 portion of the driver still supports the NoAccel option.

[Gordon Jin (gordon-jin)]

(In reply to comment #7)
> I've pushed driver fixes for this to master in patch:
>
> d655a3ff423e69c19a5dc07140cbf3caaa32cb86 Remove NoAccel support.
>
> There's an associated fix necessary in the kernel to bump the framebuffer limit
> from 2048 to 4096 for KMS which should land shortly.

Keith, I see the xf86-video-intel fix, but I can't find the kernel fix in drm-intel-next.

X still fails to start (with 4096 set) with message: "failed to add fb"

[noisymime (josh-noisymime)]

This may become a problem for 9.10 as the fix in the upstream bug has both a driver and kernel portion. Assuming karmic is planning to release with 2.6.30, the fix that has been pushed to 2.6.31 will not apply and the problem will remain.

Given that karmic only has UXA available, this will mean i945 users will be unable to get a desktop larger than 2048x2048 on 9.10 at all.

[Gordon Jin (gordon-jin)]

I've seen the kernel fix in drm-intel-next:
drm/i915: Allow frame buffers up to 4096x4096 on 915/945 class hardware

And verified 945GM works with the fixes for both KMS and UMS.

[Gordon Jin (gordon-jin)]

But 8xx still suffers so I'm changing the summary and decreasing priority.

[Keith Packard (keithp)]

8xx cannot scanout from buffers wider that 8192 bytes, limiting it to 2048 pixels. Hence the limit must remain lower for 8xx chips.

[Bryce Harrington (bryce)]

We already are on the 2.6.31 kernel, so should have that fix.

[Gordon Jin (gordon-jin)]

*** Bug 23237 has been marked as a duplicate of this bug. ***

[Gordon Jin (gordon-jin)]

*** Bug 25075 has been marked as a duplicate of this bug. ***

[C Michal (michal-physics)]

In comment #7, it sounds like there is a fix needed for this to work with KMS enabled. With all components of the 2009Q3 release (but kernel 2.6.32-rc7) this still seems to be missing - with KMS enabled, xrandr tells me the screensize is limited to 2048x2048 still, but with KMS disabled, that goes up to 4096x4096.

Did that fix get left behind somewhere?

I ask partly because it appears framebuffer compression gets disabled (according to Xorg.0.log anyway) if KMS is not enabled, so it would appear that at the moment one has to choose between bigger screens (no KMS) or framebuffer compression (KMS).

[Keith Packard (keithp)]

For KMS, you need kernel patch 5e4d6fa72619aeea271d2ad704757717b06e291a5e4d6fa72619aeea271d2ad704757717b06e291a as well. That shipped in 2.6.31.

[Shuang-he (shuang-he)]

(In reply to comment #17)
> For KMS, you need kernel patch
> 5e4d6fa72619aeea271d2ad704757717b06e291a5e4d6fa72619aeea271d2ad704757717b06e291a
> as well. That shipped in 2.6.31.
>

Guess it's a Copy&Paste error.
should be 5e4d6fa72619aeea271d2ad704757717b06e291a

[C Michal (michal-physics)]

Sorry, I'm a moron. Thanks for the quick answers.

I got that backwards. It appears to me as though large screens only work if KMS is enabled, and framebuffer compression gets disabled if KMS is enabled.
(on a 945GME - in a dell mini-9).

[Gordon Jin (gordon-jin)]

(In reply to comment #19)
> Sorry, I'm a moron. Thanks for the quick answers.
>
> I got that backwards. It appears to me as though large screens only work if
> KMS is enabled,

That's expected.

> and framebuffer compression gets disabled if KMS is enabled.

That's probably bug#23767. I'm going to reopen it.