Bug 93802

Summary:

[IVB bisected] switching to tty1 causes fifo underrun on pipe B and pipe C

Product:

DRI

Reporter:

Chris Bainbridge <chris.bainbridge>

Component:

DRM/Intel

Assignee:

Intel GFX Bugs mailing list <intel-gfx-bugs>

Status:

CLOSED FIXED

QA Contact:

Intel GFX Bugs mailing list <intel-gfx-bugs>

Severity:

normal

Priority:

medium

CC:

frederik.schwan, intel-gfx-bugs, iskatu, tomxtobin

Version:

DRI git

Keywords:

bisected, regression

Hardware:

Other

OS:

All

Whiteboard:

i915 platform:

IVB

i915 features:

display/watermark

Attachments:

Description	Flags
dmesg with drm.debug	none

Description Chris Bainbridge 2016-01-20 20:48:09 UTC

Created attachment 121163 [details]
dmesg with drm.debug

Reproduce: Connect 3 displays, boot to Xorg, press ctrl-alt-f1
Result: fifo underrun, both displays power off

dmesg:

[    9.755511] [drm:intel_check_cpu_fifo_underruns] *ERROR* fifo underrun on pipe B
[    9.755513] [drm:intel_check_cpu_fifo_underruns] *ERROR* fifo underrun on pipe C
[    9.755519] [drm:intel_check_pch_fifo_underruns] *ERROR* pch fifo underrun on pch transcoder B
[    9.755523] [drm:intel_check_pch_fifo_underruns] *ERROR* pch fifo underrun on pch transcoder C
[    9.761398] [drm:intel_check_cpu_fifo_underruns] *ERROR* fifo underrun on pipe B
[    9.761400] [drm:intel_check_cpu_fifo_underruns] *ERROR* fifo underrun on pipe C
[    9.761407] [drm:intel_check_pch_fifo_underruns] *ERROR* pch fifo underrun on pch transcoder B
[    9.761411] [drm:intel_check_pch_fifo_underruns] *ERROR* pch fifo underrun on pch transcoder C
[    9.774117] [drm:intel_check_cpu_fifo_underruns] *ERROR* fifo underrun on pipe C
[    9.774125] [drm:intel_check_pch_fifo_underruns] *ERROR* pch fifo underrun on pch transcoder C


bisect result (commit was merged in to the Linus tree 3 days ago in 984065055e6e):


92826fcdfc147a7d16766e987c12a9dfe1860c3f is the first bad commit
commit 92826fcdfc147a7d16766e987c12a9dfe1860c3f
Author: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Date:   Thu Dec 3 13:49:13 2015 +0100

    drm/i915: Calculate watermark related members in the crtc_state, v4.
    
    This removes pre/post_wm_update from intel_crtc->atomic, and
    creates atomic state for it in intel_crtc.
    
    Changes since v1:
    - Rebase on top of wm changes.
    Changes since v2:
    - Split disable_cxsr into a separate patch.
    Changes since v3:
    - Move some of the changes to intel_wm_need_update.
    
    Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
    Link: http://patchwork.freedesktop.org/patch/msgid/56603A49.5000507@linux.intel.com
    Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

:040000 040000 b97b4b2338e1da2ee9e93791154b4deb2ecaf8b6 ae91735a668b6785e55122c646dbca93b54eb8c9 M	drivers

Comment 1 Chris Bainbridge 2016-01-26 11:36:42 UTC

Shutdown log shows all pipes overflow when Xorg exits:


[ 1015.463379] [drm:intel_set_cpu_fifo_underrun_reporting] *ERROR* uncleared fifo underrun on pipe A
[ 1015.463386] [drm:intel_cpu_fifo_underrun_irq_handler] *ERROR* CPU pipe A FIFO underrun
[ 1015.463400] [drm:intel_set_pch_fifo_underrun_reporting] *ERROR* uncleared pch fifo underrun on pch transcoder A
[ 1015.463403] [drm:intel_pch_fifo_underrun_irq_handler] *ERROR* PCH transcoder A FIFO underrun
[ 1015.572966] [drm:intel_check_cpu_fifo_underruns] *ERROR* fifo underrun on pipe B
[ 1015.572967] [drm:intel_check_cpu_fifo_underruns] *ERROR* fifo underrun on pipe C
[ 1015.572970] [drm:intel_check_pch_fifo_underruns] *ERROR* pch fifo underrun on pch transcoder B
[ 1015.572973] [drm:intel_check_pch_fifo_underruns] *ERROR* pch fifo underrun on pch transcoder C
[ 1015.582403] [drm:intel_check_cpu_fifo_underruns] *ERROR* fifo underrun on pipe B
[ 1015.582405] [drm:intel_check_cpu_fifo_underruns] *ERROR* fifo underrun on pipe C
[ 1015.582411] [drm:intel_check_pch_fifo_underruns] *ERROR* pch fifo underrun on pch transcoder B
[ 1015.582415] [drm:intel_check_pch_fifo_underruns] *ERROR* pch fifo underrun on pch transcoder C
[ 1015.593548] [drm:intel_check_cpu_fifo_underruns] *ERROR* fifo underrun on pipe C
[ 1015.593553] [drm:intel_check_pch_fifo_underruns] *ERROR* pch fifo underrun on pch transcoder C

Comment 2 Ville Syrjala 2016-01-26 11:46:46 UTC

These may be worth a try:
http://patchwork.freedesktop.org/patch/msgid/1452776015-22076-2-git-send-email-ville.syrjala@linux.intel.com       
http://patchwork.freedesktop.org/patch/msgid/1452776015-22076-1-git-send-email-ville.syrjala@linux.intel.com

Comment 3 Chris Bainbridge 2016-01-26 12:15:33 UTC

No change with those patches - switching to tty1 still results in the same error. I just noticed pipe A underruns in the original dmesg, but that monitor did not go to standby (monitors are same model).

Comment 4 frederik 2016-02-20 21:20:40 UTC

Same Problem here.
First occured after upgrade to 4.4 and still exists in 4.5rc4.

Comment 5 Jani Saarinen 2016-12-09 11:13:38 UTC

Is this issue still seen with latest kernel?

Comment 6 Chris Bainbridge 2016-12-13 00:16:35 UTC

I don't see this any more with 4.9.0

Comment 7 yann 2016-12-13 06:53:10 UTC

(In reply to Chris Bainbridge from comment #6)
> I don't see this any more with 4.9.0

Thanks Chris for your feedback. Closing as fixed.

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