From patchwork Fri Jul 1 22:47:56 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Navare, Manasi" X-Patchwork-Id: 9210553 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 AEFD96075F for ; Fri, 1 Jul 2016 22:36:01 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A1E11286C7 for ; Fri, 1 Jul 2016 22:36:01 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 96A7F286CE; Fri, 1 Jul 2016 22:36:01 +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=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 99E23286C7 for ; Fri, 1 Jul 2016 22:36:00 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 20AA46E1D4; Fri, 1 Jul 2016 22:35:59 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by gabe.freedesktop.org (Postfix) with ESMTP id D79116E1D4 for ; Fri, 1 Jul 2016 22:35:57 +0000 (UTC) Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga104.fm.intel.com with ESMTP; 01 Jul 2016 15:35:57 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos; i="5.26,559,1459839600"; d="scan'208"; a="1009210123" Received: from manasi-otcmedia.jf.intel.com ([10.7.199.175]) by orsmga002.jf.intel.com with ESMTP; 01 Jul 2016 15:35:57 -0700 From: Manasi Navare To: intel-gfx@lists.freedesktop.org Date: Fri, 1 Jul 2016 15:47:56 -0700 Message-Id: <1467413276-27024-1-git-send-email-manasi.d.navare@intel.com> X-Mailer: git-send-email 1.9.1 Subject: [Intel-gfx] [PATCH] drm/i915: intel_dp_check_link_status should only return status of link X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP Intel_dp_check_link_status() function reads the Link status registers and returns a boolean to indicate link is good or bad. If the link is bad, it is retrained outside the function based on the return value. Signed-off-by: Manasi Navare --- drivers/gpu/drm/i915/intel_dp.c | 41 ++++++++++++++++++++++++----------------- 1 file changed, 24 insertions(+), 17 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 6d586b7..c795c9e 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -3863,7 +3863,7 @@ go_again: return -EINVAL; } -static void +static bool intel_dp_check_link_status(struct intel_dp *intel_dp) { struct intel_encoder *intel_encoder = &dp_to_dig_port(intel_dp)->base; @@ -3873,26 +3873,25 @@ intel_dp_check_link_status(struct intel_dp *intel_dp) WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex)); if (!intel_dp_get_link_status(intel_dp, link_status)) { - DRM_ERROR("Failed to get link status\n"); - return; + DRM_DEBUG_KMS("Failed to get link status\n"); + return false; } - if (!intel_encoder->base.crtc) - return; + /* Check if the link is valid by reading the bits of Link status + * registers + */ + if (!drm_dp_channel_eq_ok(link_status, intel_dp->lane_count) || + !drm_dp_clock_recovery_ok(link_status, intel_dp->lane_count)) { + DRM_DEBUG_KMS("Channel EQ or CR not ok, need to retrain\n"); + return false; + } - if (!to_intel_crtc(intel_encoder->base.crtc)->active) - return; + DRM_DEBUG_KMS("Link is good, no need to retrain\n"); + return true; - /* if link training is requested we should perform it always */ - if ((intel_dp->compliance_test_type == DP_TEST_LINK_TRAINING) || - (!drm_dp_channel_eq_ok(link_status, intel_dp->lane_count))) { - DRM_DEBUG_KMS("%s: channel EQ not ok, retraining\n", - intel_encoder->base.name); - intel_dp_start_link_train(intel_dp); - intel_dp_stop_link_train(intel_dp); - } } + /* * According to DP spec * 5.1.2: @@ -3950,7 +3949,11 @@ intel_dp_short_pulse(struct intel_dp *intel_dp) } drm_modeset_lock(&dev->mode_config.connection_mutex, NULL); - intel_dp_check_link_status(intel_dp); + if (!intel_dp_check_link_status(intel_dp) || + intel_dp->compliance_test_type == DP_TEST_LINK_TRAINING) { + intel_dp_start_link_train(intel_dp); + intel_dp_stop_link_train(intel_dp); + } drm_modeset_unlock(&dev->mode_config.connection_mutex); return true; @@ -4271,7 +4274,11 @@ intel_dp_long_pulse(struct intel_connector *intel_connector) * link loss triggerring long pulse!!!! */ drm_modeset_lock(&dev->mode_config.connection_mutex, NULL); - intel_dp_check_link_status(intel_dp); + if (!intel_dp_check_link_status(intel_dp) || + intel_dp->compliance_test_type == DP_TEST_LINK_TRAINING) { + intel_dp_start_link_train(intel_dp); + intel_dp_stop_link_train(intel_dp); + } drm_modeset_unlock(&dev->mode_config.connection_mutex); goto out; }