drm/radeon: disable force performance state when thermal state is active

If the thermal state is active, we are in the lowest performance level
to cool down the chip.  Don't let the user force it higher.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/radeon_pm.c

@@ -508,17 +508,21 @@ static ssize_t radeon_set_dpm_forced_performance_level(struct device *dev,
 	} else if (strncmp("auto", buf, strlen("auto")) == 0) {
 		level = RADEON_DPM_FORCED_LEVEL_AUTO;
 	} else {
-		mutex_unlock(&rdev->pm.mutex);
 		count = -EINVAL;
 		goto fail;
 	}
 	if (rdev->asic->dpm.force_performance_level) {
+		if (rdev->pm.dpm.thermal_active) {
+			count = -EINVAL;
+			goto fail;
+		}
 		ret = radeon_dpm_force_performance_level(rdev, level);
 		if (ret)
 			count = -EINVAL;
 	}
-	mutex_unlock(&rdev->pm.mutex);
 fail:
+	mutex_unlock(&rdev->pm.mutex);
+
 	return count;
 }