From 951caa6acf7121f88a9e8e04ef75bd0ac323a033 Mon Sep 17 00:00:00 2001 From: Alex Deucher 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 Cc: stable@vger.kernel.org --- drivers/gpu/drm/radeon/radeon_pm.c | 6 ++++++ 1 file changed, 6 insertions(+) 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 */