Hi to everyone,
I'm experiencing a strange behaviour on some STCK1A8LFC device.
At our software house we developed a Qt5 based digital signage solution running under Ubuntu Linux.
This software works perfectly under Ubuntu 14.04.3 on another intel based machine, powered by Intel HD Graphics driver.
Under STCK1A8LFC we experience random freezes of HDMI output (note, just the output is frozen because the device stills respond to network requests and if I capture a screenshot using "xwd" command the screenshot is correctly showing the image that should be on the screen). The screen looks frozen, but the device still work correctly. The problem happens randomly after a few days of uninterrupted working; I can alto cause it (but not every time) if I disconnect and reconnect the HDMI cable, or if the monitor itself goes into power-saving mode. The defect happens more frequently if we use VAAPI acceleration.
We tried everything to avoid this strange behaviour; the only one solution we found is a reboot every day, but the application should run h24 without interruption. On other platforms (eg: Intel NUC) everything works correctly.
We are using kernel 3.16.0-57-generic from Ubuntu.
Under Xorg we enabled SNA acceleration and TearFree mode, but the problem still exists with TearFree disabled.
Xorg logs about the driver shows this:
[ 12.836] (II) Module intel: vendor="X.Org Foundation"
[ 12.836] compiled for 1.16.0, module version = 2.99.914
[ 12.836] Module class: X.Org Video Driver
[ 12.836] ABI class: X.Org Video Driver, version 18.0
[ 12.836] (II) intel: Driver for Intel(R) Integrated Graphics Chipsets:
i810, i810-dc100, i810e, i815, i830M, 845G, 854, 852GM/855GM, 865G,
915G, E7221 (i915), 915GM, 945G, 945GM, 945GME, Pineview GM,
Pineview G, 965G, G35, 965Q, 946GZ, 965GM, 965GME/GLE, G33, Q35, Q33,
GM45, 4 Series, G45/G43, Q45/Q43, G41, B43
[ 12.837] (II) intel: Driver for Intel(R) HD Graphics: 2000-6000
[ 12.837] (II) intel: Driver for Intel(R) Iris(TM) Graphics: 5100, 6100
[ 12.837] (II) intel: Driver for Intel(R) Iris(TM) Pro Graphics: 5200, 6200, P6300
[ 12.837] (--) using VT number 7
[ 12.855] (II) intel(0): Using Kernel Mode Setting driver: i915, version 1.6.0 20080730
[ 12.855] (II) intel(0): SNA compiled: xserver-xorg-video-intel-lts-utopic 2:2.99.914-1~exp1ubuntu4.5~trusty1 (Timo Aaltonen <email@example.com>)
[ 12.855] (II) intel(0): SNA compiled for use with valgrind
[ 12.856] (--) intel(0): Integrated Graphics Chipset: Intel(R) HD Graphics
[ 12.856] (--) intel(0): CPU: x86-64, sse2, sse3, ssse3, sse4.1, sse4.2
Thanks to everyone who can help.