From patchwork Thu May 24 19:04:05 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= X-Patchwork-Id: 10425335 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 E970060327 for ; Thu, 24 May 2018 19:04:17 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BAB2029678 for ; Thu, 24 May 2018 19:04:17 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id ADCD4296A3; Thu, 24 May 2018 19:04:17 +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=-5.2 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham 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 BC5AB29678 for ; Thu, 24 May 2018 19:04:11 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0BD736E63A; Thu, 24 May 2018 19:04:11 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by gabe.freedesktop.org (Postfix) with ESMTPS id A1BBD6E635 for ; Thu, 24 May 2018 19:04:09 +0000 (UTC) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 24 May 2018 12:04:09 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.49,436,1520924400"; d="scan'208";a="58243769" Received: from stinkbox.fi.intel.com (HELO stinkbox) ([10.237.72.174]) by fmsmga001.fm.intel.com with SMTP; 24 May 2018 12:04:07 -0700 Received: by stinkbox (sSMTP sendmail emulation); Thu, 24 May 2018 22:04:06 +0300 From: Ville Syrjala To: intel-gfx@lists.freedesktop.org Date: Thu, 24 May 2018 22:04:05 +0300 Message-Id: <20180524190406.2973-1-ville.syrjala@linux.intel.com> X-Mailer: git-send-email 2.16.1 MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH 1/2] drm/i915: Try to suppress more spurious PCH underruns on ILK-IVB X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP From: Ville Syrjälä My ILK seems to generate a spurious PCH underrun with most interlaced HDMI modes. Add a second vblank wait to avoid it. We have seen some spurious PCH underruns still in CI as well, some of which seem to be progressive DP. The logs also point towards some spurious underrins with progressive HDMI on SNB. While I don't have a solid explanation for those let's try to kill all the birds with one stone and always do the double wait. Buzilla: https://bugs.freedesktop.org/show_bug.cgi?id=106387 Signed-off-by: Ville Syrjälä Acked-by: Chris Wilson --- drivers/gpu/drm/i915/intel_display.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 7604fbda0607..b5fa4943372a 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -5528,9 +5528,16 @@ static void ironlake_crtc_enable(struct intel_crtc_state *pipe_config, if (HAS_PCH_CPT(dev_priv)) cpt_verify_modeset(dev, intel_crtc->pipe); - /* Must wait for vblank to avoid spurious PCH FIFO underruns */ - if (intel_crtc->config->has_pch_encoder) + /* + * Must wait for vblank to avoid spurious PCH FIFO underruns. + * And a second vblank wait is needed at least on ILK with + * some interlaced HDMI modes. Let's do the double wait always + * in case there are more corner cases we don't know about. + */ + if (intel_crtc->config->has_pch_encoder) { + intel_wait_for_vblank(dev_priv, pipe); intel_wait_for_vblank(dev_priv, pipe); + } intel_set_cpu_fifo_underrun_reporting(dev_priv, pipe, true); intel_set_pch_fifo_underrun_reporting(dev_priv, pipe, true); }