From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 52840C433DB for ; Mon, 11 Jan 2021 18:28:53 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E6B582250E for ; Mon, 11 Jan 2021 18:28:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E6B582250E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 7858A89D1D; Mon, 11 Jan 2021 18:28:52 +0000 (UTC) Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTPS id A5DCE89D1D for ; Mon, 11 Jan 2021 18:28:50 +0000 (UTC) IronPort-SDR: 3SXsPNgH46k6BE3+n9YpE+pyQB7Na453g7Mbzkm9VX2QBVr20yodQEbA/QFiMzJ9Lwy4kbwKUl 9bp2cXgLMPyg== X-IronPort-AV: E=McAfee;i="6000,8403,9861"; a="164994817" X-IronPort-AV: E=Sophos;i="5.79,339,1602572400"; d="scan'208";a="164994817" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Jan 2021 10:28:49 -0800 IronPort-SDR: g+1IEO2p0ByabU5dFT58Umhcj72I5LPYltmx7jZBYXrWtImg0chulumHScQErcqhJY2ID1lwXx Y6pF62Ho5gtQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.79,339,1602572400"; d="scan'208";a="388927339" Received: from stinkbox.fi.intel.com (HELO stinkbox) ([10.237.72.174]) by orsmga007.jf.intel.com with SMTP; 11 Jan 2021 10:28:45 -0800 Received: by stinkbox (sSMTP sendmail emulation); Mon, 11 Jan 2021 20:28:45 +0200 Date: Mon, 11 Jan 2021 20:28:45 +0200 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= To: intel-gfx@lists.freedesktop.org Message-ID: References: <20210107182026.24848-1-ville.syrjala@linux.intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210107182026.24848-1-ville.syrjala@linux.intel.com> X-Patchwork-Hint: comment Subject: Re: [Intel-gfx] [PATCH 1/2] drm/i915: Try to use fast+narrow link on eDP again and fall back to the old max strategy on failure X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Matteo Iervasi , Jani Nikula , Albert Astals Cid , Kai-Heng Feng , Emanuele Panigati Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Thu, Jan 07, 2021 at 08:20:25PM +0200, Ville Syrjala wrote: > From: Ville Syrj=E4l=E4 > = > Some new eDP panels don't like to operate at the max parameters, and > instead we need to go for an optimal confiugration. That unfortunately > doesn't work with older eDP panels which are generally only guaranteed > to work at the max parameters. > = > To solve these two conflicting requirements let's start with the optimal > setup, and if that fails we start again with the max parameters. The > downside is probably an extra modeset when we switch strategies but > I don't see a good way to avoid that. > = > For a bit of history we first tried to go for the fast+narrow in > commit 7769db588384 ("drm/i915/dp: optimize eDP 1.4+ link config > fast and narrow"). but that had to be reverted due to regression > on older panels in commit f11cb1c19ad0 ("drm/i915/dp: revert back > to max link rate and lane count on eDP"). So now we try to get > the best of both worlds by using both strategies. Pushed. Fingers crossed for no regressions... -- = Ville Syrj=E4l=E4 Intel _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx