drm/radeon/ci: disable mclk switching for high refresh rates (v2)

commit ab03d9f upstream. Even if the vblank period would allow it, it still seems to be problematic on some cards. v2: fix logic inversion (Nils) bug: https://bugs.freedesktop.org/show_bug.cgi?id=96868 Acked-by: Christian König <[email protected]> Signed-off-by: Alex Deucher <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
NXPower · Jul 27, 2017 · a844f8d · a844f8d
1 parent b85007c
commit a844f8d
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/drivers/gpu/drm/radeon/ci_dpm.c b/drivers/gpu/drm/radeon/ci_dpm.c
@@ -776,6 +776,12 @@ bool ci_dpm_vblank_too_short(struct radeon_device *rdev)
 	u32 vblank_time = r600_dpm_get_vblank_time(rdev);
 	u32 switch_limit = pi->mem_gddr5 ? 450 : 300;
 
+	/* disable mclk switching if the refresh is >120Hz, even if the
+        * blanking period would allow it
+        */
+	if (r600_dpm_get_vrefresh(rdev) > 120)
+		return true;
+
 	/* disable mclk switching if the refresh is >120Hz, even if the
         * blanking period would allow it
         */