The patch below does not apply to the 3.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 951caa6acf7121f88a9e8e04ef75bd0ac323a033 Mon Sep 17 00:00:00 2001 From: Alex Deucher <alexander.deucher@xxxxxxx> Date: Wed, 18 Feb 2015 00:59:45 -0500 Subject: [PATCH] drm/radeon: disable mclk switching with 120hz+ monitors These tend to be problematic even if the vblank period is long enough. This needs more investigation across a wider range of displays. Disable for now. bugs: https://bugs.freedesktop.org/show_bug.cgi?id=87796 https://bugs.freedesktop.org/show_bug.cgi?id=89198 Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Cc: stable@xxxxxxxxxxxxxxx diff --git a/drivers/gpu/drm/radeon/radeon_pm.c b/drivers/gpu/drm/radeon/radeon_pm.c index 9f758d39420d..33cf4108386d 100644 --- a/drivers/gpu/drm/radeon/radeon_pm.c +++ b/drivers/gpu/drm/radeon/radeon_pm.c @@ -852,6 +852,12 @@ static struct radeon_ps *radeon_dpm_pick_power_state(struct radeon_device *rdev, single_display = false; } + /* 120hz tends to be problematic even if they are under the + * vblank limit. + */ + if (single_display && (r600_dpm_get_vrefresh(rdev) >= 120)) + single_display = false; + /* certain older asics have a separare 3D performance state, * so try that first if the user selected performance */ -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html