Bug 100386

Summary: i915.enable_rc6=1 causes flickering
Product: DRI Reporter: Adam Wolk <adam.wolk>
Component: DRM/IntelAssignee: Intel GFX Bugs mailing list <intel-gfx-bugs>
Status: CLOSED INVALID QA Contact: Intel GFX Bugs mailing list <intel-gfx-bugs>
Severity: normal    
Priority: medium CC: adam.wolk, intel-gfx-bugs
Version: unspecified   
Hardware: x86-64 (AMD64)   
OS: Linux (All)   
Whiteboard:
i915 platform: HSW i915 features: power/runtime PM

Description Adam Wolk 2017-03-25 13:49:06 UTC 
I noticed my external display constantly turning on and off (like with resolution changes) and randomly shaking (horizontal minimal left/right movement) unless a DRI app is active (ie. running DRI_PRIME=1 glxgears).

Booting the system with i915.enable_rc6=0 removes the issue.

The amd driver being the cause was ruled out in https://bugs.freedesktop.org/show_bug.cgi?id=100058

[mulander@napalm ~]$ uname -a
Linux napalm 4.10.1-1-ARCH #1 SMP PREEMPT Sun Feb 26 21:08:53 UTC 2017 x86_64 GNU/Linux


[mulander@napalm ~]$ lspci
00:00.0 Host bridge: Intel Corporation Haswell-ULT DRAM Controller (rev 0b)
00:02.0 VGA compatible controller: Intel Corporation Haswell-ULT Integrated Graphics Controller (rev 0b)
00:03.0 Audio device: Intel Corporation Haswell-ULT HD Audio Controller (rev 0b)
00:14.0 USB controller: Intel Corporation 8 Series USB xHCI HC (rev 04)
00:16.0 Communication controller: Intel Corporation 8 Series HECI #0 (rev 04)
00:1b.0 Audio device: Intel Corporation 8 Series HD Audio Controller (rev 04)
00:1c.0 PCI bridge: Intel Corporation 8 Series PCI Express Root Port 3 (rev e4)
00:1c.3 PCI bridge: Intel Corporation 8 Series PCI Express Root Port 4 (rev e4)
00:1c.4 PCI bridge: Intel Corporation 8 Series PCI Express Root Port 5 (rev e4)
00:1d.0 USB controller: Intel Corporation 8 Series USB EHCI #1 (rev 04)
00:1f.0 ISA bridge: Intel Corporation 8 Series LPC Controller (rev 04)
00:1f.2 SATA controller: Intel Corporation 8 Series SATA Controller 1 [AHCI mode] (rev 04)
00:1f.3 SMBus: Intel Corporation 8 Series SMBus Controller (rev 04)
01:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 10)
02:00.0 Network controller: Qualcomm Atheros QCA9565 / AR9565 Wireless Network Adapter (rev 01)
03:00.0 Display controller: Advanced Micro Devices, Inc. [AMD/ATI] Sun LE [Radeon HD 8550M / R5 M230]
Comment 1 Chris Wilson 2017-03-27 09:19:58 UTC 
It is unlikely that rc6 is the active ingredient here, but when disabling rc6 one of its side-effects is to disable runtime powermanagement.
Comment 2 Jani Nikula 2017-03-27 19:08:39 UTC 
Side note, all bets are off when setting non-default i915.enable_rc6 values.
Comment 3 Jani Saarinen 2017-05-24 07:18:44 UTC 
Reporter, is this still valid?
Comment 4 Elizabeth 2017-06-23 22:02:55 UTC 
(In reply to Jani Saarinen from comment #3)
> Reporter, is this still valid?

Changing to INVALID, if there is any new information related to this bug, please share the information and change to REOPEN. Thank you.

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