From patchwork Fri May 18 12:13:30 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jani Nikula X-Patchwork-Id: 10410249 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 14837602C2 for ; Fri, 18 May 2018 12:11:06 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F1E392894B for ; Fri, 18 May 2018 12:11:05 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id EEEF828988; Fri, 18 May 2018 12:11:05 +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 DC82A28988 for ; Fri, 18 May 2018 12:11:02 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 26FB36ED44; Fri, 18 May 2018 12:11:02 +0000 (UTC) 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 ESMTPS id C82606ED42 for ; Fri, 18 May 2018 12:11:00 +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 fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 18 May 2018 05:11:00 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.49,414,1520924400"; d="scan'208";a="56423670" Received: from jnikula-mobl2.fi.intel.com (HELO localhost) ([10.237.72.62]) by fmsmga001.fm.intel.com with ESMTP; 18 May 2018 05:10:57 -0700 From: Jani Nikula To: Lucas De Marchi , intel-gfx@lists.freedesktop.org In-Reply-To: <20180516172110.19191-1-lucas.demarchi@intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20180516172110.19191-1-lucas.demarchi@intel.com> Date: Fri, 18 May 2018 15:13:30 +0300 Message-ID: <878t8hxitx.fsf@intel.com> MIME-Version: 1.0 Subject: Re: [Intel-gfx] [PATCH] Revert "drm/i915/edp: Do not do link training fallback or prune modes on EDP" 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: , Cc: Daniel Vetter , Dave Airlie Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP On Wed, 16 May 2018, Lucas De Marchi wrote: > This reverts commit c0cfb10d9e1de490e36d3b9d4228c0ea0ca30677. > > This fails on a Dell XPS13 9350 machine giving me just a black screen. > [drm:intel_dp_start_link_train [i915]] [CONNECTOR:59:eDP-1] Link Training Passed at Link Rate = 540000, Lane count = 4 > [drm:intel_dp_start_link_train [i915]] *ERROR* [CONNECTOR:59:eDP-1] Link Training failed at link rate = 540000, lane count = 4 > [drm:intel_dp_start_link_train [i915]] [CONNECTOR:59:eDP-1] Link Training Passed at Link Rate = 540000, Lane count = 4 > [drm:intel_dp_start_link_train [i915]] [CONNECTOR:59:eDP-1] Link Training Passed at Link Rate = 540000, Lane count = 4 > [drm:intel_dp_start_link_train [i915]] [CONNECTOR:59:eDP-1] Link Training Passed at Link Rate = 540000, Lane count = 4 > [drm:intel_dp_start_link_train [i915]] *ERROR* [CONNECTOR:59:eDP-1] Link Training failed at link rate = 540000, lane count = 4 > [drm:intel_dp_start_link_train [i915]] *ERROR* [CONNECTOR:59:eDP-1] Link Training failed at link rate = 540000, lane count = 4 > [drm:intel_dp_start_link_train [i915]] [CONNECTOR:59:eDP-1] Link Training Passed at Link Rate = 540000, Lane count = 4 > [drm:intel_dp_start_link_train [i915]] *ERROR* [CONNECTOR:59:eDP-1] Link Training failed at link rate = 540000, lane count = 4 > [drm:intel_dp_start_link_train [i915]] [CONNECTOR:59:eDP-1] Link Training Passed at Link Rate = 540000, Lane count = 4 > [drm:intel_dp_start_link_train [i915]] [CONNECTOR:59:eDP-1] Link Training Passed at Link Rate = 540000, Lane count = 4 > [drm:intel_dp_start_link_train [i915]] *ERROR* [CONNECTOR:59:eDP-1] Link Training failed at link rate = 540000, lane count = 4 > > On a working kernel, previous to this commit I have: > [drm:intel_dp_start_link_train [i915]] [CONNECTOR:59:eDP-1] Link Training failed at link rate = 540000, lane count = 4 > [drm:intel_dp_start_link_train [i915]] [CONNECTOR:59:eDP-1] Link Training Passed at Link Rate = 270000, Lane count = 4 We had this kind of issues *before* any link fallback, way back when we just plunged on ignoring issues. Actually I imagined we were going to do that for eDP when c0cfb10d9e1d ("drm/i915/edp: Do not do link training fallback or prune modes on EDP") was introduced, but looks like we don't. Does this work? It might not, because way back we used to have a full clock recovery step within channel eq error path, and that then worked just fine. BR, Jani. diff --git a/drivers/gpu/drm/i915/intel_dp_link_training.c b/drivers/gpu/drm/i915/intel_dp_link_training.c index 3fcaa98b9055..7315ee01f984 100644 --- a/drivers/gpu/drm/i915/intel_dp_link_training.c +++ b/drivers/gpu/drm/i915/intel_dp_link_training.c @@ -323,7 +323,8 @@ intel_dp_start_link_train(struct intel_dp *intel_dp) { struct intel_connector *intel_connector = intel_dp->attached_connector; - if (!intel_dp_link_training_clock_recovery(intel_dp)) + if (!intel_dp_link_training_clock_recovery(intel_dp) && + !intel_dp_is_edp(intel_dp)) goto failure_handling; if (!intel_dp_link_training_channel_equalization(intel_dp)) goto failure_handling;