[drm:intel_set_cpu_fifo_underrun_reporting]

[Petko Manolov]

On 16-06-13 13:29:46, Petko Manolov wrote:
> 	Hello guys,
> 
> Running xorg on my Lenovo Yoga 2 Pro (MY2013) on recent kernels turn into a 
> major PITA.  After a couple of minutes the screen starts to flicker and only 
> killing xorg or reboot fixes the problem.  This is what i typically see in 
> dmesg:
> 
> 
> [    0.000000] microcode: microcode updated early to revision 0x1d, date = 2015-08-13
> [    0.000000] Linux version 4.7.0-rc3 (petkan at yoga) (gcc version 6.1.1 20160519 (Debian 6.1.1-4) ) #5 SMP Mon Jun 13 12:41:31 EEST 2016
> [    0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-4.7.0-rc3 root=/dev/sda1 ro quiet
> ...
> [    0.104213] smpboot: CPU0: Intel(R) Core(TM) i7-4500U CPU @ 1.80GHz (family: 0x6, model: 0x45, stepping: 0x1)
> ...
> [    1.033691] [drm] Initialized drm 1.1.0 20060810
> [    1.034106] [drm] Memory usable by graphics device = 2048M
> [    1.034108] [drm] Replacing VGA console driver
> [    1.040787] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
> [    1.040788] [drm] Driver supports precise vblank timestamp query.
> [    1.066820] [drm] Initialized i915 1.6.0 20160425 for 0000:00:02.0 on minor 0
> [    1.231007] fbcon: inteldrmfb (fb0) is primary device
> [    2.524538] i915 0000:00:02.0: fb0: inteldrmfb frame buffer device
> ...
> [   92.825302] [drm:intel_set_cpu_fifo_underrun_reporting] *ERROR* uncleared fifo underrun on pipe A
> [   92.825312] [drm:ironlake_irq_handler] *ERROR* CPU pipe A FIFO underrun
> 
> 
> This is going on for all v4.6 kernel releases as well as v4.7-rcX.  Older, 
> v4.4 and v4.5, kernels are running fine.  I'm using Debian testing updated to 
> 2016-06-13.
> 
> I'd be happy to help with testing so please let me know if there's anything i 
> can do for you.

It seems that James (Bottomley) has similar problem and it was suggested to him 
to try drm-intel-nightly.  Which i did, but it didn't help much.  Admittedly, 
the flicker issue showed up after about an hour instead of a couple of minutes.

The 'dmesg' output seems very much like what i posted above.


cheers,
Petko