drm/radeon/r5xx-r7xx: wait for the MC to settle after MC blackout

Some chips seem to need a little delay after blacking out the MC before the requests actually stop. Stop DMAR errors reported by Shuah Khan. Reported-by: Shuah Khan <shuahkhan@gmail.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
mariux64 · Jan 31, 2013 · 39dc9aa · 39dc9aa
1 parent ed39fad
commit 39dc9aa
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/drivers/gpu/drm/radeon/rv515.c b/drivers/gpu/drm/radeon/rv515.c
@@ -336,6 +336,8 @@ void rv515_mc_stop(struct radeon_device *rdev, struct rv515_mc_save *save)
 				WREG32(R600_CITF_CNTL, blackout);
 		}
 	}
+	/* wait for the MC to settle */
+	udelay(100);
 }
 
 void rv515_mc_resume(struct radeon_device *rdev, struct rv515_mc_save *save)