From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugzilla-daemon@freedesktop.org Subject: [Bug 102646] Screen flickering under amdgpu-experimental [buggy auto power profile] Date: Thu, 06 Sep 2018 12:06:10 +0000 Message-ID: References: Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============0863367547==" Return-path: Received: from culpepper.freedesktop.org (culpepper.freedesktop.org [131.252.210.165]) by gabe.freedesktop.org (Postfix) with ESMTP id 8FA1A6E694 for ; Thu, 6 Sep 2018 12:06:10 +0000 (UTC) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: dri-devel@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org --===============0863367547== Content-Type: multipart/alternative; boundary="15362355701.CaBE95ad.10808" Content-Transfer-Encoding: 7bit --15362355701.CaBE95ad.10808 Date: Thu, 6 Sep 2018 12:06:10 +0000 MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://bugs.freedesktop.org/ Auto-Submitted: auto-generated https://bugs.freedesktop.org/show_bug.cgi?id=3D102646 --- Comment #30 from L.Y. Sim --- I have this issue on a 3840x1600 Acer XR382CQK with an RX560 with Kernel 4.18.5-1 on Manjaro.=20 When I set the refresh rate to 75Hz, severe artifacts and flickering appear. Both=20 echo high > /sys/class/drm/card0/device/power_dpm_force_performance_lev= el and echo low > /sys/class/drm/card0/device/power_dpm_force_performance_level stop the flickering and artifacting, and I can see via=20 cat /sys/class/drm/card0/device/pp_dpm_mclk=20 that the memory clocks are set to 1750Mhz and 300Mhz respectively.=20 However, if /sys/class/drm/card0/device/power_dpm_force_performance_level is set to auto, I can see (via watching /sys/class/drm/card0/device/pp_dpm_mclk with time intervals around 0.1s), that the memory clock oscillates rapidly between 300Mhz, 625Mhz and 1750Mhz. So it seems to me that the rapid change in memory frequency is what's causi= ng the flickering. --=20 You are receiving this mail because: You are the assignee for the bug.= --15362355701.CaBE95ad.10808 Date: Thu, 6 Sep 2018 12:06:10 +0000 MIME-Version: 1.0 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://bugs.freedesktop.org/ Auto-Submitted: auto-generated

Comme= nt # 30 on bug 10264= 6 from L.Y. Sim 
I have this issue on a 3840x1600 Acer XR382CQK with an RX560 w=
ith Kernel
4.18.5-1 on Manjaro.=20

When I set the refresh rate to 75Hz, severe artifacts and flickering appear.

Both=20

    echo high > /sys/class/drm/card0/device/power_dpm_force_performance_=
level
and

    echo low > /sys/class/drm/card0/device/power_dpm_force_performance_l=
evel

stop the flickering and artifacting, and I can see via=20

    cat /sys/class/drm/card0/device/pp_dpm_mclk=20

that the memory clocks are set to 1750Mhz and 300Mhz respectively.=20

However, if /sys/class/drm/card0/device/power_dpm_force_performance_level is
set to auto, I can see (via watching /sys/class/drm/card0/device/pp_dpm_mclk
with time intervals around 0.1s), that the memory clock oscillates rapidly
between 300Mhz, 625Mhz and 1750Mhz.

So it seems to me that the rapid change in memory frequency is what's causi=
ng
the flickering.

You are receiving this mail because:
  • You are the assignee for the bug.
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