Bug 1082815

Summary:	ARM Kernels 3.13+ have no working display when using a DTB
Product:	[Fedora] Fedora	Reporter:	Paul Whalen <pwhalen>
Component:	kernel	Assignee:	Kyle McMartin <kmcmartin>
Status:	CLOSED CURRENTRELEASE	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	rawhide	CC:	awilliam, gansalmon, info, itamar, jonathan, kai.reichert, kernel-maint, kwizart, madhu.chinakonda, mchehab, pbrobinson, peterm, satellitgo, wcohen
Target Milestone:	---
Target Release:	---
Hardware:	arm
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2014-09-23 17:42:35 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	245418

Description Paul Whalen 2014-03-31 21:12:33 UTC

Description of problem:
When booting with a DTB using kernels 3.13+ all platforms lack a working display. Booting without a DTB in vexpress continues to work. 

This seems to affect all boards tested - specifically the Trimslice and Pandaboard which were working prior.

Comment 1 Kai Reichert 2014-04-21 20:13:17 UTC

I can confirm this on a pandaboard. In the meantime it can boot with a DTB for current kernels on fedora 20, but the HDMI display is not working.

In prior kernel versions without DTB I a get display at full 1920x1080 pixel resolution.

Comment 2 Paul Whalen 2014-05-27 14:31:17 UTC

Display is working again on the Pandaboard in kernel-3.15.0-0.rc5.git2.10.fc21+ using rawhide nightlies.

Comment 3 Adam Williamson 2014-07-30 17:54:28 UTC

F20 is now on a 3.15 kernel in stable updates. Does this mean this is fixed for F20/F21/F22 now? F19 is still on 3.14.

Comment 4 Josh Boyer 2014-07-30 18:01:49 UTC

FYI, F19 is staying on 3.14.y until EOL.  If 3.15 is required for this bug then users will need to migrate to F20.

Comment 5 info@kobaltwit.be 2014-09-05 10:03:31 UTC

I recently installed Fedora 20 on my trimslice. This installer image works well, however after a system update to Kernel 3.15.10 there is no longer output on the hdmi port.

I talked about this yesterday on the #fedora-arm irc channel. The problem is that the tegra_drm module is not added to initrd.

Manually running "modprobe tegra_drm" restores the output on the hdmi port.

When I asked about the cause of this, I got this reply:
[Thursday 04 September 2014] [18:56:32] <nchauvet> issue with the way dracut detect the drm driver, fixed in f22 dracut

Fedora 22 is still a long way ahead of us. So would it be possible to backport this fix to Fedora 20 ?

Comment 6 Nicolas Chauvet (kwizart) 2014-09-05 10:19:03 UTC

(In reply to info from comment #5)
..
> I talked about this yesterday on the #fedora-arm irc channel. The problem is
> that the tegra_drm module is not added to initrd.
The autoloading of the tegra_drm is fixed with backport of:
ApplyPatch arm-tegra-drmdetection.patch
that is currently available on kernel 3.16.
This kernel should hit f20 updates at some point.