Bug 31375 - Unsupported: 8bpp framebuffer
Summary: Unsupported: 8bpp framebuffer
Status: RESOLVED WONTFIX
Alias: None
Product: xorg
Classification: Unclassified
Component: Driver/intel (show other bugs)
Version: unspecified
Hardware: x86 (IA32) Linux (All)
: lowest enhancement
Assignee: Carl Worth
QA Contact: Intel GFX Bugs mailing list
URL:
Whiteboard:
Keywords:
: 31378 (view as bug list)
Depends on:
Blocks:
 
Reported: 2010-11-04 01:54 UTC by Joacim Thomassen
Modified: 2013-02-23 09:10 UTC (History)
0 users

See Also:
i915 platform:
i915 features:


Attachments
Xorg.0.log (32.93 KB, text/plain)
2010-11-04 02:10 UTC, Joacim Thomassen
no flags Details
dmesg w/ drm.debug=0x06 (90.30 KB, text/plain)
2010-11-04 02:11 UTC, Joacim Thomassen
no flags Details
Output from: `xrandr -d :0 -q` (325 bytes, text/plain)
2010-11-04 02:12 UTC, Joacim Thomassen
no flags Details
Output from: intel_gpu_dump (83.72 KB, application/x-gzip)
2010-11-04 02:13 UTC, Joacim Thomassen
no flags Details
Output from: /sys/devices/pci0000:00/0000:00:02.0/rom (64.00 KB, application/octet-stream)
2010-11-04 02:14 UTC, Joacim Thomassen
no flags Details
Running `xinit -fg black -bg lightgrey -- /usr/bin/Xorg -depth 8 :0` (74.66 KB, image/jpeg)
2010-11-08 02:46 UTC, Joacim Thomassen
no flags Details
dmesg w/drm.debug=0x06 (Redux) (122.80 KB, text/plain)
2010-12-15 05:53 UTC, Joacim Thomassen
no flags Details
Xorg.0.log, 8bpp (Redux) (23.82 KB, text/plain)
2010-12-15 05:54 UTC, Joacim Thomassen
no flags Details
Xorg.0.log, 15bpp (Redux) (23.79 KB, text/plain)
2010-12-15 05:55 UTC, Joacim Thomassen
no flags Details
Xorg.0.log diff, 8bpp vs 15bpp (Redux) (847 bytes, text/plain)
2010-12-16 03:14 UTC, Joacim Thomassen
no flags Details
xvinfo 8bpp (Redux) (61 bytes, text/plain)
2010-12-16 04:13 UTC, Joacim Thomassen
no flags Details
xvinfo 15bpp (Redux) (1.34 KB, text/plain)
2010-12-16 04:14 UTC, Joacim Thomassen
no flags Details
xorg.conf used only for the 16vs15-comparison (89 bytes, text/plain)
2010-12-17 05:26 UTC, Joacim Thomassen
no flags Details
Xorg.0.log, 16bpp, DRI=off, (16vs15-comparison) (22.38 KB, text/plain)
2010-12-17 05:28 UTC, Joacim Thomassen
no flags Details
Xorg.0.log, 15bpp, DRI=off, (16vs15-comparison) (22.47 KB, text/plain)
2010-12-17 05:29 UTC, Joacim Thomassen
no flags Details
Xorg.0.log diff, DRI=off (16vs15-comparison) (578 bytes, text/plain)
2010-12-17 05:33 UTC, Joacim Thomassen
no flags Details
xf86cmap: Use old palette system for pseudocolour. (1.52 KB, patch)
2011-01-05 06:24 UTC, Michel Dänzer
no flags Details | Splinter Review
Running patched `xinit -- /tmp/xorg/bin/Xorg -depth 8 :0` (60.14 KB, image/jpeg)
2011-01-14 04:26 UTC, Joacim Thomassen
no flags Details
Exiting from the X screen in attachment 42017 (70.38 KB, image/jpeg)
2011-01-14 04:28 UTC, Joacim Thomassen
no flags Details
Running patched `xinit -fg black -bg lightgrey -- /tmp/xorg/bin/Xorg -depth 8 :0` (44.91 KB, image/jpeg)
2011-01-14 04:29 UTC, Joacim Thomassen
no flags Details
Sudden color mapish change from executing `ls` in X screen seen in attachment 42019 (66.80 KB, image/jpeg)
2011-01-14 04:32 UTC, Joacim Thomassen
no flags Details
Xorg.0.log, 8bpp, patched X-server (23.29 KB, text/plain)
2011-01-16 22:51 UTC, Joacim Thomassen
no flags Details
Patch to disable driver for depth 8 (it just doesn't work). (995 bytes, patch)
2013-02-22 22:47 UTC, Carl Worth
no flags Details | Splinter Review

Description Joacim Thomassen 2010-11-04 01:54:30 UTC
System environment:
Chipset: Arrandale - Intel Core i5 M450 CPU
Arch: i686
libdrm: 2.4.22-1.fc14
mesa-dri: 7.9-1.fc14
xorg: 1.9.0-15.fc14
intel-drv: 2.12.0-6.fc14
kernel: 2.6.35.6-45.fc14
distro: Fedora 14
machine: Acer Aspire 3820T, model MS2292, TimelineX laptop
display connector: LVDS1

Reproducible: 100%

Steps to reproduce:
1. Install Fedora 14, without KDE, GNOME - only X Window system
2. Log in on first tty
3. Run `xinit -- /usr/bin/Xorg -depth 8 :0`

Result: 
X server starts without complains, but the X display 0 on tty6 is totally black.

Expected result (as experienced running `xinit -- /usr/bin/Xorg :0`):
The X display 0 is shown with it's patterned root window and a white xterm.
Comment 1 Joacim Thomassen 2010-11-04 02:10:51 UTC
Created attachment 40033 [details]
Xorg.0.log
Comment 2 Joacim Thomassen 2010-11-04 02:11:24 UTC
Created attachment 40034 [details]
dmesg w/ drm.debug=0x06
Comment 3 Joacim Thomassen 2010-11-04 02:12:08 UTC
Created attachment 40035 [details]
Output from: `xrandr -d :0 -q`
Comment 4 Joacim Thomassen 2010-11-04 02:13:02 UTC
Created attachment 40036 [details]
Output from: intel_gpu_dump
Comment 5 Joacim Thomassen 2010-11-04 02:14:23 UTC
Created attachment 40037 [details]
Output from: /sys/devices/pci0000:00/0000:00:02.0/rom
Comment 6 Joacim Thomassen 2010-11-04 02:49:28 UTC
Correction:

tty6 -> tty7
Comment 7 Chris Wilson 2010-11-07 08:59:01 UTC
*** Bug 31378 has been marked as a duplicate of this bug. ***
Comment 8 Joacim Thomassen 2010-11-08 02:05:42 UTC
Yes, you are absolutely right Chris. The Bug 31378 is a duplicate of this. I assumed the difference (greyscale vs. total blackness) on screen was due to the AccelMethod XAA vs. UXA, but the deprecation of the XAA+intel possibility is obvious from the Xorg.0.log.

I've researched further to try to nail down what caused the differing screen appearance, and found this:

Starting the X server like this (all with this BUGs setup, no xorg.conf):
`xinit -fg black -bg lightgrey -- /usr/bin/Xorg -depth 8 :0`

Do give a greyscale screen comparable to the one I reported in Bug 31378, see attached image greyscale-xterm.jpg

By the way, the cursor is visible and do change appearance over the xterm window either way (total darkness or greyscale xterm).
Comment 9 Chris Wilson 2010-11-08 02:22:23 UTC
There are a couple of potential causes at play here and I haven't dug into either yet. The first is that we are simply misrendering when asked to generate an 8-bit framebuffer. The second is that we not doing the correct modesetting for an 8-bit framebuffer. Both are extremely likely; the latter almost definitely.
Comment 10 Joacim Thomassen 2010-11-08 02:46:27 UTC
Created attachment 40115 [details]
Running `xinit -fg black -bg lightgrey -- /usr/bin/Xorg -depth 8 :0`
Comment 11 Joacim Thomassen 2010-11-09 06:03:28 UTC
Built and tested latest stable 2D driver

intel-drv: 2.13.0 (2010Q3 from intellinuxgraphics.org)

Result: The same dark greyscale display problem persist.
Comment 12 Joacim Thomassen 2010-12-15 05:11:42 UTC
Bug Redux - latest and greatest - still greyish to me

System environment:
Chipset: Arrandale - Intel Core i5 M450 CPU
Arch: i686
libdrm: 2.4.23-2.fc15
mesa-dri: 7.10-0.15.fc15
xorg: 1.9.99.1-2.20101201.fc15
intel-drv: 2.13.902 (git commit 71af40a75fbdd1054b1111e8cbe67ad1f97e6613)
kernel: 2.6.37-0.rc5.git2.1.fc15
xrandr: 1.3.4
distro: Fedora Rawhide (14-15)
machine: Acer Aspire 3820T, model MS2292, TimelineX laptop
display connector: LVDS2

Reproducible: 100%

Steps to reproduce:
1. Install Fedora Rawhide (hmm.. somewhat reproducible)
2. Log in on first tty
3. Run `xinit -- /usr/bin/Xorg -depth 8 :0`

Result: The same dark greyscale display problem persist. X server starts without complaints, but the X display 0 on tty7 is very dark, almost black.

As before, running:
`xinit -fg black -bg lightgrey -- /usr/bin/Xorg -depth 8 :0`

Do give a greyscale screen where I can actually see the xterm window. Listing directories with colored ls output reveal the lack of colors. It's all grey, comparable to the earlier attached image for running this command.

Running with depth 15 do give a result that is worse than with depth 8. Not even the fg/bg trick do yield a discernible xterm from the dark display.

Expected result (as experienced running `xinit -- /usr/bin/Xorg :0`):
The X display 0 is able to display colors and avoid the darkness.
Comment 13 Joacim Thomassen 2010-12-15 05:53:15 UTC
Created attachment 41140 [details]
dmesg w/drm.debug=0x06 (Redux)
Comment 14 Joacim Thomassen 2010-12-15 05:54:40 UTC
Created attachment 41141 [details]
Xorg.0.log, 8bpp (Redux)
Comment 15 Joacim Thomassen 2010-12-15 05:55:10 UTC
Created attachment 41142 [details]
Xorg.0.log, 15bpp (Redux)
Comment 16 Joacim Thomassen 2010-12-16 03:14:45 UTC
Created attachment 41163 [details]
Xorg.0.log diff, 8bpp vs 15bpp (Redux)
Comment 17 Joacim Thomassen 2010-12-16 04:12:14 UTC
The difference in brightness between 15bpp and 8bpp seems strange. As the Xorg.0.log diff attached show there are a couple of lines that differ.

15bpp has default Visual TrueColor vs. 8bpp having PseudoColor.

To see if the choice of Visual did affect the brightness, I added xorg.conf:

Section "Screen"
    Identifier "MyScreen"
    SubSection "Display"
        Depth 15
        Visual "PseudoColor"
    EndSubSection
EndSection

Restarted with:
xinit -fg black -bg lightgrey -- /usr/bin/Xorg -depth 15 :0

Result: Nothing changed. 15bpp still darker than 8bpp.
Comment 18 Joacim Thomassen 2010-12-16 04:13:41 UTC
Created attachment 41165 [details]
xvinfo 8bpp (Redux)
Comment 19 Joacim Thomassen 2010-12-16 04:14:12 UTC
Created attachment 41166 [details]
xvinfo 15bpp (Redux)
Comment 20 Joacim Thomassen 2010-12-16 04:17:50 UTC
The Xv difference between 8bpp and 15bpp in Xorg.0.log seems interesting as the attached xvinfo output shows. But I'm delving far into the unknown here...
Comment 21 Joacim Thomassen 2010-12-17 05:26:41 UTC
Created attachment 41209 [details]
xorg.conf used only for the 16vs15-comparison
Comment 22 Joacim Thomassen 2010-12-17 05:28:52 UTC
Created attachment 41210 [details]
Xorg.0.log, 16bpp, DRI=off, (16vs15-comparison)
Comment 23 Joacim Thomassen 2010-12-17 05:29:51 UTC
Created attachment 41211 [details]
Xorg.0.log, 15bpp, DRI=off, (16vs15-comparison)
Comment 24 Joacim Thomassen 2010-12-17 05:33:33 UTC
Created attachment 41212 [details]
Xorg.0.log diff, DRI=off (16vs15-comparison)
Comment 25 Joacim Thomassen 2010-12-17 05:42:01 UTC
16vs15-comparison

If Xorg.0.log tell the truth and DRI really is disabled for both 16bpp and 15bpp then the only differences left that could explain the extreme difference in display output is (seen in the attachments):

* RGB weight
* video overlay key

What are they? Is this possible, or is it more to it beyond the log?
Comment 26 Michel Dänzer 2011-01-05 06:24:29 UTC
Created attachment 41664 [details] [review]
xf86cmap: Use old palette system for pseudocolour.

Does this xserver patch help?
Comment 27 Joacim Thomassen 2011-01-14 04:18:04 UTC
Patch applied - colorful and unstable

System environment:
Chipset: Arrandale - Intel Core i5 M450 CPU
Arch: i686
libdrm: (git commit 550fe2ca3b29ad2191eab4fdfbed9ed21e25492d)
mesa-dri: (git commit 63528c4510e4891a13c255871b1dd5c2dafdb02c)
xorg: 1.9.99.901 (1.10.0 RC 1) 
  (git commit 6358a60065eef167d4e5f4afd981ff26deeba80d)
intel-drv: 2.14.0 (git commit fd9235ebe03a01982238cdd6e8b55f613e14b6af)
kernel: 2.6.37-2.fc15
xrandr: 1.3.4 (git commit b94179dd0538c73ff4628d43f4b8f492351ddd9c)
distro: Fedora Rawhide (14-15)
machine: Acer Aspire 3820T, model MS2292, TimelineX laptop
display connector: LVDS2

Reproducible: 100%

Steps to reproduce:
1. Install Fedora Rawhide (hmm.. somewhat reproducible)
2. Log in on first tty
3. Build X according to http://xorg.freedesktop.org/wiki/ModularDevelopersGuide
4. export LD_LIBRARY_PATH=/tmp/xorg/lib
5. Run `xinit -- /tmp/xorg/bin/Xorg -depth 8 :0`

Result: The X display 0 on tty7 is *very* colorful. See attachment: Running patched `xinit -- /tmp/xorg/bin/Xorg -depth 8 :0`

As before, running:
`xinit -fg black -bg lightgrey -- /tmp/xorg/bin/Xorg -depth 8 :0`
Image of screen included in attachment: Running patched `xinit -fg black -bg lightgrey -- /tmp/xorg/bin/Xorg -depth 8 :0`

Might give a perfect screen with black root window and white xterm, just the same as running with depth 16 or 24. Listing directories with colored ls output do yield a sudden change into the strange world of "bade taste" colors.

The result is not stable. Running xinit with -fg/-bg options directly after xinit without the options might give a screen with exactly the same colors instead of a perfect screen similar to 16 and 24 bpp. Changing VT do sometimes give a black screen after xinit, and reboot is necessary.

The expected result (as experienced running `xinit -- /tmp/xorg/bin/Xorg :0`):
The X display 0 is able to display colors and no sudden color mapish change occur if you do `ls --color /`.
Comment 28 Joacim Thomassen 2011-01-14 04:26:19 UTC
Created attachment 42017 [details]
Running patched `xinit -- /tmp/xorg/bin/Xorg -depth 8 :0`
Comment 29 Joacim Thomassen 2011-01-14 04:28:43 UTC
Created attachment 42018 [details]
Exiting from the X screen in attachment 42017 [details]
Comment 30 Joacim Thomassen 2011-01-14 04:29:51 UTC
Created attachment 42019 [details]
Running patched `xinit -fg black -bg lightgrey -- /tmp/xorg/bin/Xorg -depth 8 :0`
Comment 31 Joacim Thomassen 2011-01-14 04:32:58 UTC
Created attachment 42020 [details]
Sudden color mapish change from executing `ls` in X screen seen in attachment 42019 [details]
Comment 32 Joacim Thomassen 2011-01-14 05:05:33 UTC
(In reply to comment #26)
> Created an attachment (id=41664) [details]
> xf86cmap: Use old palette system for pseudocolour.
> 
> Does this xserver patch help?

Well, it certainly does something. But it seems as if other components need some more care too for this to really be helpful.

Thanks anyway Michel.
Comment 33 Joacim Thomassen 2011-01-16 22:51:05 UTC
Created attachment 42111 [details]
Xorg.0.log, 8bpp, patched X-server
Comment 34 Eric Anholt 2011-06-01 14:51:38 UTC
Rather than trying to patch things back up to make 8bpp work, I'd rather see us just reject the config early in driver setup and not support it.
Comment 35 Carl Worth 2013-02-22 22:47:46 UTC
Created attachment 75380 [details] [review]
Patch to disable driver for depth 8 (it just doesn't work).

(In reply to comment #34)
> Rather than trying to patch things back up to make 8bpp work, I'd rather see
> us just reject the config early in driver setup and not support it.

Here's a patch to do exactly that.

-Carl
Comment 36 Carl Worth 2013-02-23 01:19:57 UTC
The attached patch has now been pushed.

Thanks, all.

-Carl
Comment 37 Chris Wilson 2013-02-23 09:10:40 UTC
Woah. In hindsight, this bug was reported immediately after an Xorg release that broke our driver. The DDX and kernel did work with psuedo-color modes and we had an immediate regression report. No wonder we have a very bad reputation.


Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.