From patchwork Wed Oct 26 19:36:36 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lyude Paul X-Patchwork-Id: 9398789 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 459A460234 for ; Thu, 27 Oct 2016 00:55:45 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0F6E529E60 for ; Thu, 27 Oct 2016 00:55:45 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0422429E62; Thu, 27 Oct 2016 00:55:45 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 96D5429E60 for ; Thu, 27 Oct 2016 00:55:44 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id CC35E6E99B; Thu, 27 Oct 2016 00:55:11 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by gabe.freedesktop.org (Postfix) with ESMTPS id 46BE86E927; Wed, 26 Oct 2016 19:37:06 +0000 (UTC) Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id C92A2C0567A3; Wed, 26 Oct 2016 19:37:05 +0000 (UTC) Received: from whitewolf.lyude.com (vpn-55-83.rdu2.redhat.com [10.10.55.83]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u9QJaugD017272 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Wed, 26 Oct 2016 15:37:04 -0400 From: Lyude To: stable@vger.kernel.org Subject: [PATCH 4/5] drm/i915/skl: Don't try to update plane watermarks if they haven't changed Date: Wed, 26 Oct 2016 15:36:36 -0400 Message-Id: <1477510599-14843-5-git-send-email-lyude@redhat.com> In-Reply-To: <1477510599-14843-1-git-send-email-lyude@redhat.com> References: <1477510599-14843-1-git-send-email-lyude@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Wed, 26 Oct 2016 19:37:05 +0000 (UTC) X-Mailman-Approved-At: Thu, 27 Oct 2016 00:55:07 +0000 Cc: Lyude , intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, Hans de Goede , drm-intel-fixes@lists.freedesktop.org, dri-devel@lists.freedesktop.org, Daniel Vetter X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP commit ccebc23b57c313229526dc76383ce82f5e0b9001 upstream i915 sometimes needs to disable planes in the middle of an atomic commit, and then reenable them later in the same commit. Because of this, we can't make the assumption that the state of the plane actually changed. Since the state of the plane hasn't actually changed, neither have it's watermarks. And if the watermarks hasn't changed then we haven't populated skl_results with anything, which means we'll end up zeroing out a plane's watermarks in the middle of the atomic commit without restoring them later. Simple reproduction recipe: - Get a SKL laptop, launch any kind of X session - Get two extra monitors - Keep hotplugging both displays (so that the display configuration jumps from 1 active pipe to 3 active pipes and back) - Eventually underrun Changes since v1: - Fix incorrect use of "it's" Changes since v2: - Add reproduction recipe Signed-off-by: Lyude Cc: Maarten Lankhorst Fixes: 62e0fb880123 ("drm/i915/skl: Update plane watermarks atomically during plane updates") Testcase: kms_plane Signed-off-by: Maarten Lankhorst Link: http://patchwork.freedesktop.org/patch/msgid/1472488288-27280-1-git-send-email-cpaul@redhat.com Cc: drm-intel-fixes@lists.freedesktop.org --- drivers/gpu/drm/i915/intel_display.c | 7 ++++++- drivers/gpu/drm/i915/intel_sprite.c | 8 ++++++++ 2 files changed, 14 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 8086e62..85d161a 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -3068,7 +3068,12 @@ static void skylake_disable_primary_plane(struct drm_plane *primary, struct intel_crtc *intel_crtc = to_intel_crtc(crtc); int pipe = intel_crtc->pipe; - skl_write_plane_wm(intel_crtc, &dev_priv->wm.skl_results, 0); + /* + * We only populate skl_results on watermark updates, and if the + * plane's visiblity isn't actually changing neither is its watermarks. + */ + if (!to_intel_plane_state(crtc->primary->state)->visible) + skl_write_plane_wm(intel_crtc, &dev_priv->wm.skl_results, 0); I915_WRITE(PLANE_CTL(pipe, 0), 0); I915_WRITE(PLANE_SURF(pipe, 0), 0); diff --git a/drivers/gpu/drm/i915/intel_sprite.c b/drivers/gpu/drm/i915/intel_sprite.c index d8bfff1..4178849 100644 --- a/drivers/gpu/drm/i915/intel_sprite.c +++ b/drivers/gpu/drm/i915/intel_sprite.c @@ -314,6 +314,14 @@ skl_disable_plane(struct drm_plane *dplane, struct drm_crtc *crtc) const int pipe = intel_plane->pipe; const int plane = intel_plane->plane + 1; + /* + * We only populate skl_results on watermark updates, and if the + * plane's visiblity isn't actually changing neither is its watermarks. + */ + if (!to_intel_plane_state(dplane->state)->visible) + skl_write_plane_wm(to_intel_crtc(crtc), + &dev_priv->wm.skl_results, plane); + I915_WRITE(PLANE_CTL(pipe, plane), 0); I915_WRITE(PLANE_SURF(pipe, plane), 0);