From patchwork Mon Jul 19 20:46:08 2010
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
X-Patchwork-Submitter: Chris Wilson <chris@chris-wilson.co.uk>
X-Patchwork-Id: 112794
Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177])
	by demeter.kernel.org (8.14.4/8.14.3) with ESMTP id o6JKkMrQ025032
	for <patchwork-intel-gfx@patchwork.kernel.org>;
	Mon, 19 Jul 2010 20:46:57 GMT
Received: from gabe.freedesktop.org (localhost [127.0.0.1])
	by gabe.freedesktop.org (Postfix) with ESMTP id 09CB19EADB
	for <patchwork-intel-gfx@patchwork.kernel.org>;
	Mon, 19 Jul 2010 13:46:22 -0700 (PDT)
X-Original-To: intel-gfx@lists.freedesktop.org
Delivered-To: intel-gfx@lists.freedesktop.org
Received: from mga11.intel.com (mga11.intel.com [192.55.52.93])
	by gabe.freedesktop.org (Postfix) with ESMTP id 6E95C9E779
	for <intel-gfx@lists.freedesktop.org>;
	Mon, 19 Jul 2010 13:46:12 -0700 (PDT)
Received: from fmsmga002.fm.intel.com ([10.253.24.26])
	by fmsmga102.fm.intel.com with ESMTP; 19 Jul 2010 13:44:32 -0700
X-ExtLoop1: 1
X-IronPort-AV: E=Sophos;i="4.55,228,1278313200"; d="scan'208";a="587711807"
Received: from unknown (HELO broadwater.alporthouse.com) ([10.255.17.84])
	by fmsmga002.fm.intel.com with ESMTP; 19 Jul 2010 13:45:32 -0700
From: Chris Wilson <chris@chris-wilson.co.uk>
To: intel-gfx@lists.freedesktop.org
Date: Mon, 19 Jul 2010 21:46:08 +0100
Message-Id: <1279572368-24105-1-git-send-email-chris@chris-wilson.co.uk>
X-Mailer: git-send-email 1.7.1
Subject: [Intel-gfx] [PATCH] drm/i915: Warn if we run out of FIFO space for
	a mode
X-BeenThere: intel-gfx@lists.freedesktop.org
X-Mailman-Version: 2.1.11
Precedence: list
List-Id: Intel graphics driver community testing & development
	<intel-gfx.lists.freedesktop.org>
List-Unsubscribe: <http://lists.freedesktop.org/mailman/options/intel-gfx>,
	<mailto:intel-gfx-request@lists.freedesktop.org?subject=unsubscribe>
List-Archive: <http://lists.freedesktop.org/archives/intel-gfx>
List-Post: <mailto:intel-gfx@lists.freedesktop.org>
List-Help: <mailto:intel-gfx-request@lists.freedesktop.org?subject=help>
List-Subscribe: <http://lists.freedesktop.org/mailman/listinfo/intel-gfx>,
	<mailto:intel-gfx-request@lists.freedesktop.org?subject=subscribe>
MIME-Version: 1.0
Sender: 
 intel-gfx-bounces+patchwork-intel-gfx=patchwork.kernel.org@lists.freedesktop.org
Errors-To: 
 intel-gfx-bounces+patchwork-intel-gfx=patchwork.kernel.org@lists.freedesktop.org
X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by
	milter-greylist-4.2.3 (demeter.kernel.org [140.211.167.41]);
	Mon, 19 Jul 2010 20:46:57 +0000 (UTC)


diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 9fa6711..1173a77 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2752,8 +2752,14 @@ static unsigned long intel_calculate_wm(unsigned long clock_in_khz,
 	/* Don't promote wm_size to unsigned... */
 	if (wm_size > (long)wm->max_wm)
 		wm_size = wm->max_wm;
-	if (wm_size <= 0)
+	if (wm_size <= 0) {
 		wm_size = wm->default_wm;
+		DRM_ERROR("Insufficient FIFO for plane, expect flickering:"
+			  " entries required = %ld, available = %lu.\n",
+			  entries_required + wm->guard_size,
+			  wm->fifo_size);
+	}
+
 	return wm_size;
 }