Created attachment 126666 [details]
full dmesg output with the following extra options: i915.enable_psr=0x2 log_buf_len=10M drm.debug=0x1e
Since the update from Fedora 22 to 24 and the associated upgrade of the kernel to 4.6/4.7,
the screen of my Acer Aspire V3-772G (Intel i7-4702MQ, GTX760M) has started to flicker.
The flickering starts immediately when the user login screen appears.
The flickering does happen occasionally when moving the mouse or when having something visible on the screen that moves (e.g. a watch command that has its output changed regularly or a youtube movie..).
The flickering does not occur when passing i915.enable_psr=0 to the kernel.
System: Acer Aspire V3-772G: i7-4702MQ, GTX760M (Optimus), no external display.
$ uname -m
$ uname -r
$ cat /etc/system-release
Fedora release 24 (Twenty Four)
# lspci -s 00:02.0 -v
00:02.0 VGA compatible controller: Intel Corporation 4th Gen Core Processor Integrated Graphics Controller (rev 06) (prog-if 00 [VGA controller])
Subsystem: Acer Incorporated [ALI] Device 0781
Flags: bus master, fast devsel, latency 0, IRQ 31
Memory at d3000000 (64-bit, non-prefetchable) [size=4M]
Memory at c0000000 (64-bit, prefetchable) [size=256M]
I/O ports at 5000 [size=64]
[virtual] Expansion ROM at 000c0000 [disabled] [size=128K]
Capabilities:  MSI: Enable+ Count=1/1 Maskable- 64bit-
Capabilities: [d0] Power Management version 2
Capabilities: [a4] PCI Advanced Features
Kernel driver in use: i915
Kernel modules: i915
Attached is a full dmesg output with the following extra options:
i915.enable_psr=0x2 log_buf_len=10M drm.debug=0x1e
(In reply to madebr from comment #0)
> The flickering does not occur when passing i915.enable_psr=0 to the kernel.
Does it occur *without* any i915.enable_psr option?
I've explicitly added the enable_psr option so you would know what value it had.
(In reply to madebr from comment #2)
> I've explicitly added the enable_psr option so you would know what value it
The point is, we basically only support the platform default value (i.e. no option given).
(In reply to Jani Nikula from comment #3)
> (In reply to madebr from comment #2)
> > Yes.
> > I've explicitly added the enable_psr option so you would know what value it
> > had.
> The point is, we basically only support the platform default value (i.e. no
> option given).
default is: -1 which means use per-chip for HSW system that psr is enabled (set to 1 on this platform)
please, as Jani said, confirm result without setting enable_psr option in your boot command line.
Created attachment 126701 [details]
full dmesg output with the following extra options: log_buf_len=10M drm.debug=0x1e
Created attachment 127275 [details]
fedora wayland live dmesg output: log_buf_len=10M drm.debug=0x1e
Using the Fedora Wayland Test Day Live Image, the bug is still around.
i915.enable_psr=0 keeps the flickering away
(In reply to madebr from comment #6)
> i915.enable_psr=0 keeps the flickering away
We just merged a patch to disable PSR by default:
drm/i915: disable PSR by default on HSW/BDW
This commit is marked for inclusion in the stable Kernels, so it should reach your Linux distribution at some point soon.
Thank you for your bug report. In case you think the problem still happens, please feel free to reopen the bug.
Reporter, please report if issue fixed.
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