Jan 18, 2017 - 08:19pm
Just got my Late 2016 Razer Blade Stealth QHD and installed Ubuntu 16.10 on it. Aggressive screen flickering at native resolution. Upgrading the kernel to 4.10rc4 and installing Intel Kaby Lake DMC firmware make this less aggressive/more usable but I still see the flicker occasionally. dmesg shows:
[ 182.918947] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] ERROR CPU pipe A FIFO underrun
Installing+running Intel Graphics updater for linux v2.0.3 does not help.
Hi - I checked in with some graphics devs and I'm told the underruns don't really get fixed until 4.10 - and none of the current or imminent 01.org updaters will pull in the driver from 4.10 as that is only at the rc stage, so they won't fix the underrun problems.
If you're still seeing flicker in the 4.10rc series, you can help get the bug(s) fixed by reporting them as detailed here:
Thanks for the info Vivek. I still see this even with the drm-tip tree kernel. I've commented on the bug for Kaby lake: https://bugs.freedesktop.org/show_bug.cgi?id=99344
Adding the kernel command line `i915.enable_rc6=0` fixes the issue, but it still needs to be fixed upstream. A release candidate should not have that kind of bug. See this for more info: https://www.reddit.com/r/razer/comments/5orvy5/late_2016_rbs_qhd_linux_d...
With the removal of enable_rc6 (and perhaps other "stuff") in 4.16, this bug is back. For me, the flicker happens on a late 2017 Razer Blade Stealth and, as before, just after seeing the FIFO underrun that others have reported.
I see the bug on my stock Fedora 27 installation and on a just-compiled drm-tip (4.17-rc3). I was running pretty smoothly for months with the 4.15 kernels.
Should I file a new bug for this?
Thanks and Best Regards,