Bug 37858

Summary: sandybridge GPU only supports highest resolution in 16:9 aspect
Product: xorg Reporter: tbarbarich
Component: Server/GeneralAssignee: Xorg Project Team <xorg-team>
Status: RESOLVED MOVED QA Contact: Xorg Project Team <xorg-team>
Severity: major    
Priority: high CC: ajax, Michael, mwilck
Version: unspecified   
Hardware: x86-64 (AMD64)   
OS: Linux (All)   
Whiteboard:
i915 platform: i915 features:
Attachments:
Description Flags
xrandr --verbose
none
[PATCH] xfree86: add default modes for 16:9 and 16:10 none

Description tbarbarich 2011-06-02 08:31:21 UTC
machine type:     ThinkPad T420S 
GPU SandyBridge:  HD3000 (intel core i5-2025M )
Operating System: Fedora 15 
DeskTop Manager:  Gnome 3

Problem:
The only resolution mode that's available is 1600x900 with 16:9 aspect, which is the full screen.  This is the native panel mode: highest resolution possible for panel.  Other 16:9 aspect modes are not available.

In order to verify all possible modes with 16:9 aspect, i installed windows 7 with its video driver.  As a result, all the other 16:9 modes were available and none of them blurry.  The quality was very good.  These are the 16:9 modes below that showed up in windows but not in Fedora 15/Linux.  The panel supports all these modes below. But in Fedora 15 using the intel sandybride driver that's built in to Fedora, these mode are not available.  

1440x900  16:9
1366x768  16:9
1360x768  16:9
1280x800  16:9
1280x768  16:9
1280x720  16:9
1024x768  16:9
960x600   16:9
Comment 1 Chris Wilson 2011-06-16 12:16:20 UTC
Please attach xrandr --verbose
Comment 2 tbarbarich 2011-06-16 22:57:25 UTC
Created attachment 48073 [details]
xrandr --verbose
Comment 3 Chris Wilson 2011-06-16 23:32:01 UTC
Ok, now I understand what you mean. The EDID only specifies the native mode for the panel. Quite sensible. All the other modes (Windows and Linux) are default GTF modes that are within the capabilities of the panel. It just so happens that xf86GetDefaultModes() was written in the era of 4:3 CRTs and doesn't yet attempt to generate alternate aspect modes.
Comment 4 Chris Wilson 2011-06-16 23:41:54 UTC
So in the short-term you can add the modes lines to your Xorg.conf, and in the long term we can add those defaults to hw/xfree86/etc/extramodes.c
Comment 5 tbarbarich 2011-06-17 00:10:52 UTC
(In reply to comment #4)
> So in the short-term you can add the modes lines to your Xorg.conf, and in the
> long term we can add those defaults to hw/xfree86/etc/extramodes.c


 

thank you for your help Chris!  I really appreciate this!  And i look forward to the update of extramodes.c.  Again, thank you very much.  This will be a big help to me and many others who will run into the issue.

-tony barbarich
Comment 6 Martin Wilck 2018-01-09 14:58:21 UTC
It's been 6.5 years now, and 

https://cgit.freedesktop.org/xorg/xserver/tree/hw/xfree86/common/extramodes

still doesn't contain any 16:9 or 16:10 modes.
Comment 7 Martin Wilck 2018-01-09 19:34:41 UTC
Created attachment 136636 [details] [review]
[PATCH] xfree86: add default modes for 16:9 and 16:10

Patch submitted to xorg-devel ML.
Comment 8 N. W. 2018-03-04 11:25:55 UTC
(In reply to Martin Wilck from comment #7)
> Created attachment 136636 [details] [review] [review]
> [PATCH] xfree86: add default modes for 16:9 and 16:10
> 
> Patch submitted to xorg-devel ML.

Thanks. But why is 1360x768 and 1366x768 missing?

Some panels need 1360x760 or 1366x768 instead of 1368x768.

Also, why are refresh rates such as 24Hz, 30 Hz, 50Hz, 120Hz, 144Hz missing?

Also, true 4K resolution is missing, i.e. 4096x2160.

Also, the ultra-wide resolutions are missing, such as 2560x1080, 3840x1080, 3440x1440 and so on.

Can you please fix it prior to xorg-sever 1.20?
Comment 9 Martin Wilck 2018-03-05 13:45:42 UTC
(In reply to N. W. from comment #8)

The intention of my patch was not to provide support for every mode in existence, but for "standard 16:9 and 16:10 modes". Laptops usually have mode timings about specific modes for their native resolution in the EDID data, but more often than not, reduced resolutions with the same aspect ratio are missing, making it difficult to adjust the DPI for multi monitor setups. That's why I added the extra modes list.

You are certainly right that there are more standard modes that may be missing. Feel free to add them. Write a patch.

> Can you please fix it prior to xorg-sever 1.20?

Be advised that making demands like this isn't usually helpful to motivate volunteers to do the work you'd like to see.
Comment 10 GitLab Migration User 2018-12-13 22:25:11 UTC
-- GitLab Migration Automatic Message --

This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity.

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